Browse publications by year: 2022

  1. Samat AA, Hamid ZAA, Mariatti Jaafar @ Mustapha, Yahaya BH
    Adv Exp Med Biol, 2022 Apr 08.
    PMID: 35389199 DOI: 10.1007/5584_2022_707
    The critical feature in trachea replacement is to provide a hollow cylindrical framework that is laterally stable and longitudinally flexible, facilitating cartilage and epithelial tissue formation. Despite advanced techniques and sources of materials used, most inherent challenges are related to the complexity of its anatomy. Limited blood supply leads to insufficient regenerative capacity for cartilage and epithelium. Natural and synthetic scaffolds, different types of cells, and growth factors are part of tissue engineering approaches with varying outcomes. Pre-vascularization remains one of the crucial factors to expedite the regenerative process in tracheal reconstruction. This review discusses the challenges and strategies used in tracheal tissue engineering, focusing on scaffold implantation in clinical and preclinical studies conducted in recent decades.
  2. Aruta JJBR, Maria A, Mascarenhas J
    Curr Psychol, 2022 Apr 02.
    PMID: 35400980 DOI: 10.1007/s12144-022-03054-6
    While self-compassion and mental help-seeking are two important aspects emphasized in mental health literature and counseling practice, very little research has focused on how these two are associated particularly among counseling professionals-individuals providing mental health support to others but whose mental health are often overlooked. This cross-sectional study investigated a moderated mediation model examining the role of age and attitudes in the positive influence of self-compassion on mental help-seeking intention. Using a paper-and-pencil survey, data were collected from a total of 158 Filipino counseling professionals. Results revealed that mental help-seeking attitudes significantly and partially mediated the positive association between self-compassion and mental help-seeking intention. Additionally, age significantly moderated the positive relationship between self-compassion and mental help-seeking attitudes. The significant positive influence of self-compassion on mental help-seeking attitudes was strong among older participants, weak among middle-age, and diminished among younger participants. The findings provided insights on the importance of a self-compassion-based approach to counselor training. The implications of preserving counselors' mental health in counseling practice were discussed.
  3. Htwe YZN, Mamat H, Osman B, Mahmud H
    Arab J Sci Eng, 2022 Apr 06.
    PMID: 35402141 DOI: 10.1007/s13369-022-06801-w
    The emergence of a pandemic affecting the respiratory system has resulted in a significant demand for face masks. Masks have always been mentioned as an effective tool against environmental threats. This includes the use of double masks by large sections of the public, as can be seen during the current global spread of COVID-19. However, there is limited knowledge available on the performance of the various commonly available double face masks used. In this study, we have compared the performance of single and double face configurations. Three types of 3-ply face mask (FM), three types of fabric face mask (CM) and nine configurations of these face masks were investigated based on morphology, filtration efficiencies, breathing resistance and carbon dioxide (CO2) content. The filtration efficiencies of the double face masks are enhanced when combined with a fabric mask, and were found to improve by 500% compared to those of a fabric mask. The lowest breathing resistance among the double masking was observed in the combination of FM1 and fabric face masks. From the results, it was found that all combinations of double face mask are suitable to use since the measurements indicate that the breathing resistance and CO2 contents are still lower than the acceptable value set by the Malaysian Standard (MS 2323:2010) and European Standard (EN 149:2001 + A1:2009). The performance of double masks is comparable with that of N95 respirators. The double masking combination can be used as an alternative method to reduce inhalation exposure to airborne contaminants.
  4. Lee WC, Russell B, Lau YL, Nosten F, Rénia L
    Am J Trop Med Hyg, 2022 Apr 11;106(6):1670-4.
    PMID: 35405642 DOI: 10.4269/ajtmh.21-1229
    In malaria, rosetting is a phenomenon involving the cytoadherence of uninfected erythrocytes to infected erythrocytes (IRBC) harboring the late erythrocytic stage of Plasmodium spp. Recently, artesunate-stimulated rosetting has been demonstrated to confer a survival advantage to P. falciparum late-stage IRBC. This study investigated the rosetting response of P. falciparum and P. vivax clinical isolates to ex vivo antimalarial treatments. Brief exposure of IRBC to chloroquine, mefloquine, amodiaquine, quinine, and lumefantrine increased the rosetting rates of P. falciparum and P. vivax. Furthermore, the ex vivo combination of artesunate with mefloquine and piperaquine also resulted in increased the rosetting rates. Drug-mediated rosette-stimulation has important implications for the therapeutic failure of rapidly cleared drugs such as artesunate. However, further work is needed to establish the ramifications of increased rosetting rates by drugs with longer half-lifves, such as chloroquine, mefloquine, and piperaquine.
  5. Khoo YW, Hui Teng T, Khaw YS, Li S, Chong KP
    Plant Dis, 2022 Apr 12.
    PMID: 35412330 DOI: 10.1094/PDIS-12-21-2779-PDN
    Crinum asiaticum (family Amaryllidaceae), locally known as 'Pokok Bakung', is an ornamental medicinal plant grown in Malaysia. It contains chemical compounds used for antimicrobial, antioxidant, antitumor, antiemetic and wound healing (Patel, 2017). In July 2021, 'Pokok Bakung' leaves with anthracnose symptoms were collected from a park of Universiti Malaysia Sabah in the Sabah province. The disease severity was about 100% with 20% incidence. Red spots were primarily found on the leaf surfaces. Anthracnose developed as the disease progressed, and acervuli were observed in the spots. Small pieces of infected leaves (5 x 5 mm) were excised from spot margins, surface sterilized based on Khoo et al. (2022a), placed on potato dextrose agar (PDA) in Petri dishes, which were incubated for 5 days at 25°C in the dark. The colonies formed on the PDA plates were abundant with gray-white fluffy mycelia after 5 days, and the reverse view revealed brown. UMS01, a representative isolate, was used to morphologically and molecularly characterize the fungus. Conidia were one-celled, cylindrical, hyaline, smooth, and blunt at the ends, measuring 13.8 to 16.5 x 3.6 to 6.7 µm (n = 20). Appressoria ranged in size from 7.6 to 9.3 x 5.5 to 6.9 µm (n= 20) and were ovoid to clavate, spherical to irregular in shape and dark brown in color. Genomic DNA was extracted from fresh mycelia of isolate UMS01 based on Khoo et al. (2021) with the addition of mechanical disruption using a micro pestle before heating at 95°C. PCR amplification was performed based on Khoo et al. (2022a) using ITS1/ITS4, CL1C/CL2C, ACT-512F/ACT-783R, CHS-79F/CHS-354R, and GDF1/GDR1 primer pairs to amplify the internal transcribed spacer (ITS) region, calmodulin (CAL), actin (ACT), chitin synthase (CHS-1), and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) (Weir et al. 2012). PCR products with positive amplicons were sent to Apical Scientific Sdn. Bhd. for sequencing. The sequences were deposited in GenBank under accession numbers OK458683 (ITS), OL953033 (CAL), OL953030 (ACT), OL953036 (CHS-1), and OL953039 (GAPDH). Before BLAST, the search set were adjusted to exclude model sequences (XM/XP) and the uncultured/environmental sample sequences, and limit to sequences from type material. They were 99-100% similar to the Colletotrichum siamense ITS (JX010171), CAL (JX009714), ACT (FJ907423) and CHS-1 (JX009865), and Colletotrichum changpingense GAPDH (MZ664048) type sequences. The GAPDH marker did not reliably resolve the relationships within the C. gloeosporioides complex (Vieira et al. 2020). Phylogenetic analysis using maximum likelihood based on the combined ITS, CAL, ACT, CHS-1 and GAPDH indicated that the isolate formed a supported clade (100% bootstrap value) to the most related C. siamense. Morphological and molecular characterization matched the description of C. siamense (Huang et al. 2021). Pathogenicity tests were performed to fulfil Koch's postulates by spraying a spore suspension (106 spores/ml) on the leaves of three healthy four-month-old 'Pokok Bakung' plants, while three additional plants were sprayed with water as a control. The inoculated plants were covered with plastics for 48 h at 25°C in the dark. Incubation was performed based on Iftikhar et al. (2022). Symptoms similar to those of the field collection occurred after 6 days post inoculation. No symptoms occurred on the control plants. The experiment was repeated two more times. The reisolated fungal isolates were identical to C. siamense morphologically and molecularly. Previously, C. siamense has been reported to cause anthracnose on Allamanda cathartica (Huang et al. 2021) and avocado (Li et al. 2022) in China, and 'Purple Dream' eggplant in Malaysia (Khoo et al. 2022b). Colletotrichum fructicola has been reported to cause anthracnose on C. asiaticum in China (Qing et al. 2020). To our knowledge, this is the first report of C. siamense causing anthracnose on C. asiaticum in Malaysia. Our findings expand the geographic range of C. siamense and indicate that it could be a potential threat limiting the growth and production of C. asiaticum in Malaysia.
  6. Khaw KW, Alnoor A, Al-Abrrow H, Tiberius V, Ganesan Y, Atshan NA
    Curr Psychol, 2022 Apr 13.
    PMID: 35431526 DOI: 10.1007/s12144-022-03070-6
    Regardless of the prevalence and value of change initiatives in contemporary organizations, these often face resistance by employees. This resistance is the outcome of change recipients' cognitive and behavioral reactions towards change. To better understand the causes and effects of reactions to change, a holistic view of prior research is needed. Accordingly, we provide a systematic literature review on this topic. We categorize extant research into four major and several subcategories: micro and macro reactions. We analyze the essential characteristics of the emerging field of change reactions along research issues and challenges, benefits of (even negative) reactions, managerial implications, and propose future research opportunities.
  7. Yusuf A, Mohd S
    Eur J Dev Res, 2022 Apr 19.
    PMID: 35464616 DOI: 10.1057/s41287-022-00531-3
    In spite of government counter-terrorism expenditure and efforts, the prevalence of insecurity in Nigeria appears to be rising and fast evolving into an existential crisis that is shaking the foundation of its nationhood. The current study used annual time-series data from 1980 to 2019 and the ARDL methodology to analyse the fiscal and socio-economic consequences of insecurity on economic growth in Nigeria. The empirical findings demonstrated that high unemployment rate, domestic capital formation, foreign direct investment, government spending on education and security are negatively affected by the growing level of insecurity and consequently retarded growth in the long and short run. Conversely, improved health services, equitable income distribution and productive use of public borrowing were positively correlated with security and, therefore, stimulated growth in the long and short run. Government revenue and inflation rate accelerated growth in the long run whereas their short-run effect was deleterious. The findings suggest that good governance, provision of a safe and secured environment for human capital development and businesses, improved access to social and economic services will curb violent tendencies, create jobs, reduce poverty, increase government revenue and engender long-term inclusive growth.
  8. T'ng ST, Ho KH, Pau K
    PMID: 35497075 DOI: 10.1007/s11469-022-00825-x
    Playing mobile MOBA games has become a popular leisure activity among Malaysian youth. However, MOBA games are highly addictive and have negative impacts on adult development. Inadequate local studies investigated the risk factors of excessive MOBA gameplay. The present study examined the (1) predictive role of need frustration on Internet gaming disorder (IGD) and (2) mediating effect of gaming motives. A total of 398 mobile MOBA gamers aged 18 to 29 participated in this cross-sectional online survey study. The findings showed that need frustration positively predicted IGD. Social, escape, competition, coping, and skill motives were significant mediators for the association between need frustration and IGD. However, fantasy and recreation motives were not significant mediators. MOBA players who were frustrated while fulfilling their basic needs may succumb to uncontrollable gaming behavior. Therefore, future prevention and intervention programs should cultivate positive mental strength for youth while meeting their basic needs.
  9. Huamán-Pilco AF, Huamán-Pilco J, Torres-de la Cruz M, Oliva-Cruz SM, Díaz-Valderrama JR
    Plant Dis, 2022 May 06.
    PMID: 35522958 DOI: 10.1094/PDIS-03-22-0517-PDN
    Peru is the ninth exporter of coffee (Coffea arabica) in the world, and Amazonas is among its most important producing departments (INIA 2019). In July 2021, in the nursery of the "Instituto de Investigación para el Desarrollo Sustentable de Ceja de Selva", in Huambo district (6° 26' 11.19'' S; 77° 31' 24.18'' W), four-month-old coffee seedlings cv. Catimor with 0.5-2.0 cm brown concentric leaf spots and rotten stems, bearing white mycelial tufts and black sporodochia, were observed at 30% incidence. Infected seedlings were collected. Foliar sections of 2-3 mm with infected tissue were surfaced disinfected in 2% NaClO and transferred onto Petri plates containing potato dextrose agar medium (PDA). The plates were incubated at 25° C for 7 days. We obtained three isolates (INDES-AFHP61, INDES-AFHP62 and INDES-AFHP66) with similar morphology from different seedlings. Colonies (16-17 mm diam.) formed concentric rings with white aerial mycelium, giving rise to viscous and olivaceous dark green sporodochial conidiomata. Conidia (4.82-5.77 × 1.34-1.65 µm; n = 30) were cylindric, hyaline, smooth, and aseptate. These morphological features correspond to Paramyrothecium spp. (Lombard et al. 2016). The DNA of isolates was extracted using the Wizard® Purification Kit (Promega Corp., Madison, Wisconsin), and the internal transcribed spacer 1 and 2 intervening the 5.8S subunit rDNA region (Accession numbers: OM892830 to OM892832), and part of the second-largest subunit of the RNA polymerase II, the calmodulin and the β-tubulin genes (OM919453 to OM919461) were sequenced following Lombard et al. (2016). All sequences had a percent identity greater than or equal to 99% to corresponding sequences of the P. roridum type specimen (CBS 357.89). Additionally, a multilocus Maximum Likelihood phylogenetic analysis incorporating sequence data from previous relevant studies (Lombard et al. 2016; Pinruan et al. 2022) grouped our three isolates together with the type and other specimens of P. roridum in a strongly supported clade, confirming the species identification. To evaluate pathogenicity, four-month-old coffee seedlings cv. Catimor were sprayed with 10 mL of conidial suspensions at 1 x 106 /mL. A set of control seedlings were inoculated with sterile water. Seedlings were maintained in a humidity chamber at 25 °C. After 15 days brown concentric foliar spots, stem rotting, mycelial tufts and sporodochia (same symptoms and signs observed originally at the nursery) arose in the non-control seedlings. The pathogen was re-isolated on PDA, confirming P. roridum was the causal agent of leaf spot and stem rot diseases of coffee. Paramyrothecium roridum has wide geographic distribution and host range (Lombard et al. 2016). This pathogen was reported to infect C. arabica in Mexico and Coffea sp. in Colombia (Pelayo-Sánchez et al. 2017; Lombard et al. 2016; Huaman et al. 2021). It was also reported in Africa infecting soybeans (Haudenshield et al. 2018), in Brazil infecting Tectona grandis (Borges et al. 2018), in Egypt infecting strawberries (Soliman 2020), and in Malaysia infecting Eichhornia crassipes (Hassan et al. 2021). To the best of our knowledge, this is the first time P. roridum is reported on coffee in Peru.
  10. Velez-Negron YI, Simbaña-Carrera LL, Soto-Ramos CM, Medina O, Dinkel E, Hardy C, et al.
    Plant Dis, 2022 May 10.
    PMID: 35536215 DOI: 10.1094/PDIS-01-22-0174-PDN
    In Puerto Rico, the agricultural production of pineapple (Ananas comosus (L.) Merr.) comprises nearly 5,000 tons harvested annually from over 250 ha (USDA 2018). With an annual income of approximately $3 million USD, pineapple ranks fourth in importance among Puerto Rican crops (USDA 2018). Recently, the pineapple industry on the island underwent a change from growing a local cultivar known as "Cabezona" to cultivar MD2, introduced from Hawaii around 1996 (SEA 2015), because this cultivar produces fruit more than once during a single growing season. In August 2018 (when the rainy season normally starts in Puerto Rico), soft rot symptoms appeared at commercial fields in Manatí (WGS 84 Lat 18.42694, Lng -66.44779) and persisted through 2019. Symptoms observed in the field included foliar water-soaked lesions with gas-filled blisters, especially at the base of the leaf. Leaves exhibited brown discoloration and a fetid odor (rot) at the basal portion of the plant. Finally, leaves collapsed at the center of the pineapple crown, effectively killing the apex and preventing the fruit from developing. Disease incidence ranged from 25% to 40% depending on the weather and season; when there was more rain, there was higher disease incidence. Symptomatic leaves were collected in February 2019, disinfected with 70% ethanol, and rinsed with sterile distilled water. Tissue sections (5mm2) were placed in nutrient agar. Bacterial colony-forming units (CFU) were a translucent cream color, circular, with a flat convex surface and wavy edge. Biochemical analysis showed that bacteria were Gram-negative, oxidase positive, catalase positive, and facultatively anaerobic. Pathogenicity was tested on leaves of one-and-a-half-year-old pineapple seedlings in humid chambers. Bacteria were grown on sterile nutrient agar for 3 days at 25 ± 2°C. Inoculation assays (three replications) were performed using 1X108 CFU/ml of bacteria suspended in sterile water and applied with a cotton swab to leaves wounded with a needle. The inoculated tissue was incubated at 28°C and kept in a dark environment. Negative controls were inoculated with sterile water. Five days after inoculation, foliar water-soaked lesions were observed, followed by the formation of brown leaf tissue and gas-filled blisters, the same symptoms observed in the field. A partial DNA sequence of the 16S rRNA gene of the bacterial isolate and the re-isolated bacteria were amplified using primers 27F and 1492R (Lane et al. 1985) and sequenced. The isolate was determined to the genus Dickeya through a BLAST® search against sequences available in the database of the National Center for Biotechnology Information (NCBI). This partial 16S rRNA sequence of the bacterial isolate was deposited in GenBank® at NCBI (Accession no. MT672704). To determine the identity of the Dickeya species, we sequenced the genes dnaA, gyrB, dnaX, and recN (Marrero et al. 2013) for the bacterial isolate (GenBank accession nos. OM276852, OM276853, OM276854, and OM276855) and conducted a Multilocus Sequence Analysis including reference Dickeya sequences of Marrero et al., 2013. The Phylogenetic analysis (using WinClada) resolved the Puerto Rican isolate as belonging to a clade broadly ascribable to D. zeae, most closely related to strains isolated from earlier Hawaiian pineapple bacterial heart rot outbreaks. Dickeya zeae was responsible for bacterial heart rot of pineapple in Malaysia and was later reported as the causal agent for outbreaks in Costa Rica and Hawaii (Kaneshiro et al. 2008; Sueno et al. 2014; Ramachandran et al. 2015). D. zeae had not previously been reported as causing bacterial heart rot in pineapples in Puerto Rico and this study points to a close relationship with strains first detected in Hawaii and which should further be explored to determine the precise nature of this relationship. This information should facilitate the adoption of effective control measures for this disease on the island, promote more effective methods of preventing future introductions of pathogens, and encourage further investigations into the occurrence of D. zeae on the island.
  11. Alrabadi N, Bany-Melhem S, Alzoubi KH, Alzoubi OO, Masadeh M, Abuhammad S, et al.
    PMID: 35549859 DOI: 10.2174/2772432817666220512112913
    Vaccines are important to improve immunity against pathogens and diseases. The current COVID-19 disease is rapidly evolving and spreading among people; therefore, it is important to utilize a proper vaccination strategy against it. Currently, many approved vaccines are available and accessible; however, there is a reported hesitancy against taking them among the public and even the health care workers. Mainly, this is attributed to the fear of the possible side effects and complications. Moreover, inaccurate knowledge disseminated through the media/social media especially by those who lack proper expertise adds confusion and more fear that affects the vaccination decision. For such reasons, it is essential to find strategies to increase the acceptability of vaccines and to enhance confidence in the vaccination process. This should be accompanied by sufficient efforts and proper clinical studies to confirm the value and the safety of the vaccines. Those strategies are important to avoid the further spread of the COVID-19 disease and to abort the pandemic worldwide, especially when considering the likely approach towards a COVID-19 booster vaccination program, in which booster vaccines are re-taken along intervals to adequately contain the rapidly evolving nature of the virus. This review article highlights the factors influencing the acceptability of the COVID-19 vaccination and enrollment in clinical trials among the public and some specific populations. Furthermore, it summarizes the suggested strategies and recommendations that can improve the attitudes towards COVID-19 vaccination programs.
  12. Fatmawati, Dewantara JA
    PMID: 35571877 DOI: 10.1002/casp.2611
    The Dayak indigenous community has belief and confidence in taking a stance and taking actions towards a situation and circumstances that affect their social life. This belief is based on their customs and traditions passed down from generation to generation until now. The Dayak traditional custom is a form of social resilience for the community on the border to anticipate the spread of the coronavirus disease 2019 (COVID-19) pandemic, which has become a problem in all aspects of community lives. Despite facing various issues and difficulties in dealing with the pandemic, the indigenous Dayak community in Indonesia has managed to survive and resolve these problems. In dealing with the social impact of the COVID-19 pandemic, the Salako Dayak indigenous community on the Indonesia-Malaysia border carried out a traditional ritual called Besamsam. The indigenous Salako Dayak community believes this ritual boosts the social and psychological resilience of the Salako Dayak indigenous community. The research findings showed that the Besamsam ritual had changed people's beliefs about lifestyle, behaviour and perceptions in dealing with the COVID-19 pandemic. The Besamsam ritual can specifically affect the community's personalities, attitudes and actions towards the spread of COVID-19. Indigenous peoples have become easier to organize, dynamic, empowered, resilient, motivated to meet their needs, and capable of facing various challenges and social problems during and after the COVID-19 pandemic. These findings prove that indigenous communities psychologically have strong confidence in their customary beliefs rather than cautionary advice from outside their community. The social impact of the Besamsam custom can serve as a model of awareness and a driving force for indigenous peoples' elements to work cooperatively to break the chain of COVID-19 spread.
  13. Khoo YW, Khaw YS, Tan HT, Li SF, Chong KP
    Plant Dis, 2022 May 17.
    PMID: 35581908 DOI: 10.1094/PDIS-03-22-0699-PDN
    'Thai Gold' yellow pitahaya (family Cactaceae, Selenicereus megalanthus) is a new crop being planted commercially in Malaysia. In May 2021, reddish-brown necrotic lesions were observed on the stems of approximately 60% of 'yellow pitahaya' plants in the field (~8 ha) located in the district Keningau of Sabah, Malaysia (5°20'53.1"N 116°06'23.0"E). As the disease progressed, the smaller lesions merged into larger irregularly shaped areas that formed dark brown in color. Stems with reddish-brown spot symptoms from ten plants were collected from the field and brought to the laboratory in sterilized paper bags. The symptom margin was excised into small blocks (5 x 5 x 5 mm). The blocks were surface sterilized based on Khoo et al. (2022), and placed on potato dextrose agar (PDA). The pathogens were isolated (three isolates were obtained) and cultured on potato dextrose agar (PDA) at 25°C for 5 days in the dark. The isolates developed floccose, white colony that darkened with age in PDA. Conidia (n = 30) were single celled, black, smooth, globose to subglobose, 13.9 to 18.7 μm in diameter, and borne singly on a hyaline vesicle at the tip of each conidiophore. Genomic DNA was extracted from fresh mycelia based on Khoo et al. (2021) and Khoo et al. (2022). Amplification of the internal transcribed spacer (ITS) region of rDNA, translation elongation factor 1-α (tef1-a) region and β-tubulin (tub2) genes were performed using ITS1/ITS4 (White et al. 1990), EF1-728F/EF2 (O'Donnell et al. 1998; Carbone and Kohn, 1999) and T10/Bt2b (Glass and Donaldson, 1995; O'Donnell and Cigelnik, 1997) primer sets, respectively. The products were sent to Apical Scientific Sdn. Bhd. for purification and sequencing. BLASTn analysis of the newly generated ITS (OK448496, OM832586, OM832589) were 100% identical to Nigrospora sphaerica isolate 1SS (MN339998) (507/507 bp), tef1-a (OM223859, OM826971, OM826972) were 100% identical to Nigrospora sphaerica isolate F (MT708197) (497/497 bp) and tub2 (OL697400, OM826973, OM826974) were 100% identical to Nigrospora sphaerica isolate SN180517 (MN719407) (434/434 bp). The isolates established a supported clade to the related N. sphaerica type sequences, according to phylogenetic analysis using maximum likelihood based on the concatenated ITS, tef1-a and tub2 sequences. Morphological and molecular characterization matched the description of N. sphaerica (Kee et al. 2019). Koch's postulates were performed by spray inoculation (106 spores/ml) of isolate Keningau on the stem of three 'Thai Gold' yellow pitahaya plants in growth stage 4 (BBCH code: 419) (Kishore, 2016), while water was sprayed on three mock controls. The experiment was repeated using isolate Keningau02 and Keningau03 as inoculants. The inoculated stems on yellow pitahaya plants were covered with plastics for 48 h, and the plants were maintained in a greenhouse at room temperature 25 to 28°C with a relative humidity of 80 to 90%. All the inoculated stems developed symptoms 5 days post-inoculation, whereas no symptoms occurred on mock controls, thus fulfilling the Koch's postulates. No pathogen was isolated from the mock controls. The experiments were repeated two more times for each isolate. The reisolated fungi were identical to N. sphaerica morphologically and molecularly. Previously, N. sphaerica has been reported to cause stem brown spot disease on S. megalanthus in the Philippines (Taguiam et al. 2020). To our knowledge, this is the first report of N. sphaerica causing stem brown spot on 'Thai Gold' S. megalanthus in Malaysia. Our findings serve as a warning for the authorities and farmers that the disease threat has appeared for the Malaysian yellow pitahaya production.
  14. Khoo YW, Khaw YS, Tan HT, Li SF, Chong KP
    Plant Dis, 2022 May 17.
    PMID: 35581916 DOI: 10.1094/PDIS-11-21-2478-PDN
    Pometia pinnata (family Sapindaceae), locally known as 'Kasai', is a tropical hardwood and fruit tree species grown in Malaysia. The decoction of the bark is used for the treatment of fever, sores and colds, while the fruits are edible (Adema et al. 1996). In May 2021, irregular brown spots and necrotic lesions were observed on 'Kasai' with an incidence and severity of approximately 60% and 10% on 10 plants in a nursery (5°55'30.7"N 116°04'36.2"E) in Penampang, Sabah province. When the disease progressed, the spots coalesced into extended patches, blightening the leaves and, gradually, the entire foliage. Small pieces (5 x 5 mm) of infected leaves were excised from the infected margin, and then surface sterilized according to Khoo et al. (2022b), and plated on potato dextrose agar (PDA), and cultured at 25 °C. for 6 days. Colonies were dark brown in color initially whitish on the PDA. The color of fungal colony was dark as the culture aged. Semi-appressed mycelia were observed on the plates with abundant microsclerotia engrossed in the agar. Aggregation of hyphae formed black and round to oblong or irregular shaped microsclerotia. Thirty sclerotia from a representative isolate measured average 63-171 μM length x 57-128 μM wide. The morphological features matched the description of Macrophomina phaseolina (Abd Rahim et al. 2019). The fungal genomic DNA was extracted based on Khoo et al. (2022a and 2022b). PCR was performed using primer sets ITS1/ITS4 (White et al. 1990), EF1-728/EF2 (O'Donnell et al. 1998; Carbone and Kohn, 1999) and T1/T22 (O'Donnell and Cigelnik 1997) to amplify the internal transcribed spacer (ITS) region of rDNA, translation elongation factor 1-α (TEF-1α) region and partial β-tubulin (TUB) gene. PCR products with positive amplicons were sent to Apical Scientific Sdn. Bhd. in Malaysia for sequencing. According to results (GenBank Accession No. OK465197, OM677767, ON237461), they were 100% identical with the reference sequence of Macrophomina phaseolina containing approximately 537 bp, 438 bp and 659 bp of the presented ITS, TEF-1α and TUB region (GenBank Accession No. MN629245, MN136199 and KF952208, respectively). The pathogen was identified as M. phaseolina based on its morphological and molecular data (Abd Rahim et al. 2019). To confirm the pathogenicity test, three non-wounded and healthy leaves of one-month-old 'Kasai' seedlings were inoculated with mycelium plug (1 x 1 cm) of M. phaseolina. Additional three 'Kasai' seedlings were inoculated with sterile PDA agar plug (1 x 1 cm) to serve as controls. The seedlings were monitored and incubated in a greenhouse at ambient temperature based on Iftikhar et al. (2022). After 6 days of inoculation, all infected leaves exhibited the symptoms as observed in the nursery, while the controls remained asymptomatic. The experiment was repeated twice. Re-isolation was performed from the symptomatic leaves and controls. The reisolated fungal isolates were identical to M. phaseolina morphologically and molecularly. No pathogens were isolated from the mock controls. M. phaseolina has been reported to cause leaf blight on Jasminium multiflorum in India (Mahadevakumar and Janardhana, 2016), and Crinum asiaticum and Hymenocallis littoralis in Malaysia (Abd Rahim et al. 2019). To our knowledge, this is the first report of M. phaseolina causing leaf blight on 'Kasai' in Malaysia and worldwide. Our findings serve as a warning for the authorities and farmers that the disease threat has appeared for 'Kasai' in Malaysia.
  15. Loo CC, Ng SS, Chang WS
    Microsc Microanal, 2022 May 26.
    PMID: 35616223 DOI: 10.1017/S143192762200085X
    The surging interest in manipulating the polarization of piezo/ferroelectric materials by means of light has driven an increasing number of studies toward their light-polarization interaction. One way to investigate such interaction is by performing piezoresponse force microscopy (PFM) while/after the sample is exposed to light illumination. However, caution must be exercised when analyzing and interpreting the data, as demonstrated in this paper, because sizeable photo-response observed in the PFM amplitude image of the sample is shown to be caused by the electrostatic interaction between the photo-induced surface charge and tip. Through photo-assisted Kelvin probe force microscopy (KPFM), positive surface potential is found to be developed near the sample's surface under 405 nm light illumination, whose effects on the measured PFM signal is revealed by the comparative studies on its amplitude curves that are obtained using PFM spectroscopy mode with/without illumination. This work exemplifies the need for complementary use of KPFM, PFM imaging mode, and PFM spectroscopy mode in order to distinguish real behavior from artifacts.
  16. Khoo YW, Tan HT, Khaw YS, Li SF, Chong KP
    Plant Dis, 2022 May 31.
    PMID: 35640953 DOI: 10.1094/PDIS-03-22-0566-PDN
    Selenicereus megalanthus (family Cactaceae), commonly known as yellow pitahaya is a new crop being planted commercially in Malaysia. In May 2021, stem canker symptoms with sign of black pycnidia formed on the surface of canker (30- to 55-mm in diameter) were observed on the stem of 80% of 'yellow pitahaya' plants in the field (~8 ha) located in the district Keningau of Sabah, Malaysia (5°20'53.1"N 116°06'23.0"E). The infected stems became rotted when black pycnidia formed. To isolate the pathogen, the symptom margin was excised into four small blocks (5 x 5 x 5 mm), and the blocks were surface sterilized based on Khoo et al. (2022) before plating on potato dextrose agar (PDA). Plates were incubated at 25°C for 7 days in the dark. Two isolates were obtained and were named Keningau and Keningau02. Powdery white mycelia were initially observed in two plates, and then became dark grey with age. Dark pigmentation in plates was observed after a week of incubation at 25°C in the dark. Arthroconidia (n= 30) were hyaline to dark brown, circular or cylindrical with round to truncate ends, with zero to one septum, measuring 8.9 x 5.6 µm in size. Conidia (n= 30) exuded in milky white cirrhus from pycnidia were one-celled, aseptate, oblong, measuring 10.3 × 4.6 µm in size. When reached the maturity stage, conidia were brown and septate. Genomic DNA from Keningau and Keningau02 were extracted from fresh mycelia based on Khoo et al. (2021) and Khoo et al. (2022). Amplification of the internal transcribed spacer (ITS) region of rDNA, translation elongation factor 1-α (TEF1) region and β-tubulin (TUB) genes were performed using ITS1/ITS4, EF1-728F/EF1-986R and T10/Bt2b primer sets, respectively (Carbone and Kohn, 1999; O'Donnell et al. 1997; White et al. 1990). The products were sent to Apical Scientific Sdn. Bhd. for sequencing. BLASTn analysis of the newly generated ITS (GenBank OK458559, OM649909), TEF1 (GenBank OM677768, OM677769) and TUB (GenBank OL697398, OM677766) indicated 99% identity to Neoscytalidium novaehollandiae strain CBS 122071 (GenBank MT592760). Phylogenetic analysis using maximum likelihood and Bayesian inference on the concatenated ITS-TEF1-TUB was constructed using IQ-Tree and MrBayes3.2.7. Neoscytalidium hyalinum, N. novaehollandiae and Neoscytalidium orchidacearum are reduced to synonymy with N. dimidiatum (Philips et al. 2013; Zhang et al. 2021). Although N. novaehollandiae is morphologically and phylogenetically similar to N. dimidiatum, but N. novaehollandiae produce muriform, Dichomera-like conidia that distinguish this species from other known Neoscytalidium species (Crous et al. 2006). No muriform, Dichomera-like conidia were observed in the Malaysia' isolates. The pathogen was identified as N. dimidiatum based on molecular data and morphological characterization (Serrato-Diaz and Goenaga, 2021). Pathogenicity tests were performed based on Mohd et al. (2013) by injection inoculation of 0.2 ml of conidial suspensions (1 x 106 conidia/ml) from isolate Keningau to three 30-month-old yellow pitahaya stems using a disposable needle and syringe. Distilled water was injected into three mock controls. The inoculated yellow pitahaya plants were covered with plastics for 48 h and incubated at 25°C. The pathogenicity test was also performed using isolate Keningau02. All inoculated stems developed symptoms as described after 6 days post-inoculation, whereas no symptoms occurred on controls, thus fulfilling Koch's postulates. The experiments were repeated two more times. The reisolated fungi were identical to the pathogen morphologically and molecularly. To our knowledge, this is the first report of N. dimidiatum causing stem canker on S. megalanthus in Malaysia. Our findings serve as a warning for the authorities and farmers that the disease threat has appeared in the Malaysian yellow pitahaya production.
  17. Quimbita-Reyes AM, Cabrera-Asencio I, Serrato-Diaz LM, Rivera-Vargas LI
    Plant Dis, 2022 May 31.
    PMID: 35640955 DOI: 10.1094/PDIS-01-22-0149-PDN
    Mango originated in the Indo-Burmese region (Alphonse de Candolle, 1885). In the Caribbean, Puerto Rico currently produces and exports mangoes to the United States and Europe. Globally, an important disease affecting mango production is dieback, caused by fungi belonging to Botryosphaeriaceae family. During a one-year survey from 2019 to 2020, conducted at the mango germplasm collection of the Agricultural Experiment Station of the University of Puerto Rico, located at Juana Díaz, PR, symptoms of dieback were observed in shoots, descending towards the woody part, and vascular necrosis. We sampled bimonthly, 35 Keitt trees for one year. At the end of the evaluation, we detected that a 74% disease incidence was caused by Botryosphaeriaceae. Lasiodiplodia mahajangana (syn. L. caatinguensis) was associated with 4% disease incidence. In addition, we identified other Botryosphaeriaceae species causing 70% of disease incidence. To identify the causal agent, sections of symptomatic tissue (4mm2) were surface disinfected by immersion in 70% ethanol, 10% sodium hypochlorite and rinsed with sterile-distilled water for 1 minute at each solution. Sections were transferred to petri dishes containing potato dextrose agar acidified with 85% lactic acid (aPDA). Ten fungal isolates were obtained with similar morphological characteristics such as colony color and texture, after 12 days. Of these, one representative (isolate 17) was selected and identified as L. mahajangana (Lm) using morphological parameters and sequences of four nuclear genes (Zhang, W. et al., 2021). In aPDA, Lm colonies showed sparse and slow-growing aerial mycelium with dark gray-greenish color at the center and light gray edges. Black pycnidia were observed after 15 days of incubation at 28°C and dark conditions. Hyaline, ovoid to ellipsoid immature conidia (n=40) with average size of 22 µm long and 12 µm wide were observed. Mature bicellular pigmented conidia (n=40) had longitudinal striate and its average size was 23 µm long and 12 µm wide. Internal transcribed spacer (ITS), β-tubulin (βtub), elongation factor 1-alpha (EF1-α) and large ribosomal subunit (LSU) genetic regions were amplified by PCR from the original and pathogenicity test recovered isolates. Sequences of PCR products were compared with NCBI database BLAST tool with other Lm sequences. Sequence accession numbers of the four genetic regions of Lm are as follows: OL375401 and OL375402 for the ITS region; OL405579 and OL405580 for β-tubulin; OL455922 and OL455923 for EF1-α; and OL375648 and OL375649 for LSU. All the sequences were grouped with the ex-type CMM1325 of Lm (BS=84). Pathogenicity tests were performed on 6-month-old mango trees of cv. Keitt. Three healthy trees were inoculated with 5 mm mycelial disks of Lm, on stems, with and without wounds. Controls were inoculated with aPDA disks only. Inoculated trees were covered for 3 days with plastic bags, keeping them in conditions of high relative humidity with constant irrigation, temperature of 28°C, and 12 hours of light and 12 hours of darkness for 12 days. Twelve days after inoculation, Lm isolates caused stem necrosis and canker, with differences in lesion severity from 2 to 17 mm2 with wound, and 0 to 6 mm2 without wound. Untreated controls showed no symptoms of canker. Lasiodiplodia mahajangana was re-isolated from diseased stems fulfilling Koch's postulates, and a sequence of the recovered isolate from the pathogenicity test was compared and included in the phylogenetic analysis. Lasiodiplodia mahajangana has been reported to cause stem-end rot of mango in Malaysia (Li, L. et. al., 2021). To our knowledge, this is the first report of Lm causing canker of mango in Puerto Rico. Knowing L. mahajangana as a new pathogen that causes canker of mango is important to establish an adequate and effective control management of this disease in mango producing countries worldwide.
  18. Al-Amin M, Eltayeb NM, Hossain CF, Rahiman SSF, Khairuddean M, Muhamad Salhimi S
    J Asian Nat Prod Res, 2022 Jun 04.
    PMID: 35658750 DOI: 10.1080/10286020.2022.2081562
    Bioassay-guided separation afforded furanodienone 1,10-epoxide (9) as the new compound, curcolone (10) as partially described compound and ten known compounds; germacrone (1), furanodienone (2), curzerenone (3), curcumenol (4), zederone (5), comosone II (6), (1E,4E,8R)-8-hydroxygermacra-1(10),4,7(11)-trieno-12,8-lactone (7), 13-hydroxygermacrone (8), curcuzederone (11) and demethoxycurcumin (12). The study showed that germacrone, furanodienone, curzerenone, comosone II, 13-hydroxygermacrone, curcuzederone and demethoxycurcumin are the bioactive compounds of C. aeruginosa rhizomes. Comosone II significantly inhibited MDA-MB-231 cell migration and invasion through the inhibition of MMP-9 enzyme. The present study may lead to further anticancer studies of comosone II and supports the traditional uses of C. aeruginosa rhizomes.
  19. Lai SA, Pang KY, Siau CS, Chan CMH, Tan YK, Ooi PB, et al.
    Curr Psychol, 2022 Jun 02.
    PMID: 35669207 DOI: 10.1007/s12144-022-03256-y
    This study examined the mediating role of social support in the relationship between perceived stress and nomophobia among Malaysian university students during the COVID-19 pandemic. A cross-sectional study was conducted with N = 547 university students. Participants answered a self-administered questionnaire measuring nomophobia, social support, and perceived stress. Exploratory analyses were conducted using partial least square structural equation modelling. We found that perceived stress was positively associated with nomophobia during the COVID-19 pandemic, whilst social support partially mediated the relationship between perceived stress and nomophobia. The results of this study indicated that stress may be buffered by social support in individuals with higher levels of nomophobia.
  20. Suseelan M, Chew CM, Chin H
    Curr Psychol, 2022 May 28.
    PMID: 35669209 DOI: 10.1007/s12144-022-03271-z
    The achievement gaps existed among the three types of Malaysian elementary schools with different instruction mediums. Thus, this study sought to compare the types of errors made by the low-performing students from different school types in solving word problems involving higher-order thinking skills by conducting a multiple case study. The study involved 18 low-performing students from a National Primary School (NPS), National-Type Chinese Primary School (NTCPS), and National-Type Tamil Primary School (NTTPS) in Malaysia. The students' errors in solving eight word problems were identified qualitatively through conducting four sessions of diagnostic interviews, followed by the Newman's Error Analysis. Then, a cross-case analysis was conducted. The findings indicated that the participants of the three school types made reading, comprehension, transformation, process skills and encoding errors. However, the NPS and NTTPS low-performing students made more process skills errors and encoding errors, as compared to the NTCPS low-performing students. The findings imply the need to enhance the procedural fluency of NPS and NTTPS low-performing students for reducing the achievement gaps among the school types.
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