Displaying publications 21 - 40 of 81 in total

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  1. Adlan NA, Sabri S, Masomian M, Ali MSM, Rahman RNZRA
    Front Microbiol, 2020;11:565608.
    PMID: 33013795 DOI: 10.3389/fmicb.2020.565608
    The deposition of paraffin wax in crude oil is a problem faced by the oil and gas industry during extraction, transportation, and refining of crude oil. Most of the commercialized chemical additives to prevent wax are expensive and toxic. As an environmentally friendly alternative, this study aims to find a novel thermophilic bacterial strain capable of degrading paraffin wax in crude oil to control wax deposition. To achieve this, the biodegradation of crude oil paraffin wax by 11 bacteria isolated from seawater and oil-contaminated soil samples was investigated at 70°C. The bacteria were identified as Geobacillus kaustophilus N3A7, NFA23, DFY1, Geobacillus jurassicus MK7, Geobacillus thermocatenulatus T7, Parageobacillus caldoxylosilyticus DFY3 and AZ72, Anoxybacillus geothermalis D9, Geobacillus stearothermophilus SA36, AD11, and AD24. The GCMS analysis showed that strains N3A7, MK7, DFY1, AD11, and AD24 achieved more than 70% biodegradation efficiency of crude oil in a short period (3 days). Notably, most of the strains could completely degrade C37-C40 and increase the ratio of C14-C18, especially during the initial 2 days incubation. In addition, the degradation of crude oil also resulted in changes in the pH of the medium. The degradation of crude oil is associated with the production of degradative enzymes such as alkane monooxygenase, alcohol dehydrogenase, lipase, and esterase. Among the 11 strains, the highest activities of alkane monooxygenase were recorded in strain AD24. A comparatively higher overall alcohol dehydrogenase, lipase, and esterase activities were observed in strains N3A7, MK7, DFY1, AD11, and AD24. Thus, there is a potential to use these strains in oil reservoirs, crude oil processing, and recovery to control wax deposition. Their ability to withstand high temperature and produce degradative enzymes for long-chain hydrocarbon degradation led to an increase in the short-chain hydrocarbon ratio, and subsequently, improving the quality of the oil.
    Matched MeSH terms: Paraffin
  2. Fauzah Abd Ghani, Reena Rehavu Zin, Maha Abdullah, Norhafizah Mohtarrudin, Ebenyi Emeka Onwe
    MyJurnal
    Introduction: It is well known that cancer cells evade the immune system with the help of programmed cell death protein 1 (PD-L1) molecule to remain undetected, causing abnormal proliferation of T-cells. PD-L1 expression on the surface of neoplastic cells inhibits cytotoxic T-cell responses which lead to negative regulation of cytokines and proliferation of T-cells. The deleted in colorectal cancer (DCC) gene belongs to the immunoglobulin superfamily. It is a candidate of the tumour suppressor gene by regulating apoptosis. DCC assessment gives an insight into progno-sis in patients with advanced stages of CRC. Thymidylate synthase (TYMS) is a highly conserved enzyme involved in DNA synthesis. TYMS has been an important target for cancer chemotherapy because of its central, rate-limiting role in de novo synthesis of thymidylate. Expression of PD-L1, TYMS and DCC has been demonstrated to confer a prognostic value in CRC but none have been completely validated for patient care. This study aimed to determine the prognostic and predictive potential of PD-L1, TYMS, and DCC biomarkers in CRC. Methods: The expression of these biomarkers was evaluated immunohistochemically in 91 formalin-fixed paraffin-embedded (FFPE) archival tumour samples from patients that underwent surgical resection. Results: There was high expression of DCC in most cases; 84.6% (77/91). TYMS expression at a high level score was 46.2% (42/91) and at low level was 53.8% (49/91). Majority of cases had low PD-L1 expression in 93.4% (86/91) cases and high expression was detected in 6.6% (6/94) of cases. In addition, there was a significant association between TYMS expression with gender (P < 0.05) with distribution of TYMS expression detected at high level was 76.2% in male and 23.8% in female. The Kaplan-Meier survival plot showed mean overall survival in patients with PD-L1 with high expression to be 22 months, which pre-dicts better survival. TYMS low expression showed mean overall survival of 90 which also indicated better survival. DCC high expression showed mean overall survival of 90 which indicated better survival. The correlation between the biomarkers and overall survival were not statistically significant. Conclusion: The results from this study suggest that PD-L1, TYMS and DCC expression could be used as biomarkers to predict treatment outcome in CRC. PD-L1 overexpression predicts patients who could benefit from anti-PD-1 and anti-PD-L1 immunotherapy whilst TYMS low expression predicts patients who could benefit from 5-fluorouracil therapy. DCC high expression tumours predicts a better prognosis and overall survival compared to DCC-negative tumours in advanced CRC.
    Matched MeSH terms: Paraffin Embedding
  3. Mohd Nafi SN, Siti Azrin AH, Mat Zin AA, Othman NH, Che Jalil NA
    Malays J Pathol, 2019 Apr;41(1):33-39.
    PMID: 31025635
    INTRODUCTION: Insulin-like growth factor binding protein-related protein 1 (IGFBP-rP1) is an important component of the IGF system that regulates insulin resistance-related to tumour development. The aim of this study is to investigate the expression of IGFBP-rP1 among female cancer patients who are known or not known to have Type 2 Diabetes Mellitus (T2DM).

    MATERIALS AND METHODS: Using a cross-sectional design, cases of ovarian and breast cancer with clinical status of T2DM were selected over a 10-year period in Hospital Universiti Sains Malaysia. Immunohistochemical staining for IGFBP-rP1 was performed on paraffin-embedded tissues and the results were correlated with the patient's demographic and clinicopathological data.

    RESULTS: A total of 152 breast cancer patients were recruited into the current study with 33.5% (51/152) patients were positive T2DM. Most of the breast cancer patients with T2DM were IGFBP-rP1-negative (66.7%, 34/51). The IGFBP-rP1 expression was significantly difference between breast cancer subjects with and without T2DM (p<0.001). There was no significant association of IGFBP-rP1 expression with data on the demographic and clinicopathological profiles of patients with breast cancer. Meanwhile, positive IGFBP-rP1 expression was evident in 44 out of 108 (40.74%) ovarian cancer cases. Among these cases, 36 were T2DM. In contrast to breast cancer cases, IGFBP-rP1 was mostly expressed among ovarian cancer patients with T2DM (66.7%, 24/36, p < 0.001). However, the -positive expression was not significantly associated with any sociodemographic and clinicopathological features of ovarian cancers.

    CONCLUSIONS: Majority of breast cancer patients with T2DM did not express IGFBP-rP1. In contrast, majority of the ovarian cancer patients with T2DM expressed IGFBP-rP1.

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  4. Oktiansyah R, Juliandi B, Widayati KA, Juniantito V
    Trop Life Sci Res, 2018 Jul;29(2):1-11.
    PMID: 30112137 DOI: 10.21315/tlsr2018.29.2.1
    Neuronal cell death can occur in a tissue or organ, including the brain, which affects memory. The objectives of this study were to determine the dose of bee venom that causes neuronal death and analyse the alteration of mouse behaviour, focusing in particular on spatial memory. Fifteen male mice of Deutsche Denken Yoken (DDY) strain were divided into control and treatment groups. Bee venom was injected six times for two weeks intraperitoneally with 1.88 mg/kg, 3.76 mg/kg, 5.6 mg/kg, and 7.48 mg/kg doses of venom. Brain histology was studied using haematoxylin-eosin stained paraffin embedded 5 μm coronal sections. A Y maze test was used to assay behaviour. Parameters observed were the number of dead neurons and the percentage of mice with altered behaviour. ANOVA showed that the effects of bee venom were significantly different in the case of the neuronal death parameter but were not significantly different in the case of the mice behaviour parameter. Duncan's Multiple Range Test (DMRT) demonstrated that P4 (7.48 mg/kg) gave the highest effect of bee venom to promote neuronal death.
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  5. Jenn Haw Fong, Kenny Voon, Stephen Ambu, Joon Wah Mak
    MyJurnal
    Background: The tissue specimens used for extraction of DNA in this study were from rodents trapped in four states in Peninsular Malaysia, namely Kedah, Kelantan, Selangor and Johor. Methods: Histological sections of these rodent muscle tissues stained with hematoxylin and eos in showed infection with Sarcocystis spp. Based on these results, the current study was carried out to determine the phylogenetic relationship among the identified Sarcocystis spp. in these rodents.The formalin fixed paraffin embedded (FFPE) rodent muscle blocks were subjected to DNA extraction and followed with semi nested PCR targeting 5’ and 3’ regions of 18S rRNA of Sarcocystis spp. Results: Phylogenetic analysis showed two distinct groups of Sarcocystis spp. among the rodents in Peninsular Malaysia. Most of the identified Sarcocystis spp. were genetically closely related to Sarcocystis rodentifelis and Sarcocystis muris and were also observed to be genetically closely related to Sarcocystis sp. ex Columba livia and Sarcocystis sp. cyst type I ex Anser albifrons. Conclusion: Further classification to confirm these Sarcocystis spp. was not possible as only partial sequences of 18S rRNA was available and this was insufficient for
    optimal differentiation.
    Matched MeSH terms: Paraffin
  6. Rajandram R, Razack AH, Ng KL, Gobe GC
    J Kidney Cancer VHL, 2016;3(1):1-11.
    PMID: 28326275 DOI: 10.15586/jkcvhl.2016.47
    Although primary localised tumours of renal cell carcinoma (RCC) can be treated relatively successfully with surgery, metastatic RCC has poor prognosis because of late diagnosis and resistance to therapies. In the present study, we were interested in profiling the protein expression of "inhibitor of caspase-activated DNase" (ICAD), an apoptosis inhibitor, in kidney cancer and its paired normal kidney. Immunohistochemistry with automated batch staining and morphometry using digital pathology were used to compare ICAD in 121 RCC specimens with their paired normal kidney tissue. Tissue microarray of formalin-fixed, paraffin-embedded archival tissue was used. Intensity and localisation of ICAD were compared between normal and cancer samples, and against grading within the cancers. The results demonstrated that, in this cohort, ICAD was highly expressed in the proximal tubular epithelium of normal kidney, and significantly decreased in clear cell RCC tissue (p < 0.05) as well as other subtypes of RCC (p < 0.01) compared with normal kidney. There was a tendency towards nuclear localisation of ICAD in clear cell RCC, but not in other subtypes of RCC. No significant association was found between ICAD intensity and grade of RCC. In summary, down-regulation of ICAD occurs in RCC. ICAD normally inhibits DNA fragmentation and apoptosis; thus, its down-regulation was unexpected in a cancer known for its resistance to apoptosis. However, these RCC samples were from primary, not metastatic, RCC sites, and down-regulated ICAD may be part of a progressive pathway that promotes RCC metastasis.
    Matched MeSH terms: Paraffin Embedding
  7. Sudiono, J., Zain, R.B.
    Ann Dent, 2003;10(1):-.
    MyJurnal
    Proliferating Cell Nuclear Antigen (PCNA) is one of the several markers of cellular proliferation. Epithelial proliferations play a significant role in the behaviour of odontogenic lesions. The objective of this study was to describe and compare the distribution of PCNA expression within the epithelial linings of odontogenic cysts. A total of 49 cases of odontogenic cysts consisting of 18 radicular cysts, 16 dentigerous cysts, 15 odontogenic keratocysts (OKCs) was studied. All tissues were processed routinely prior to embedding in paraffin. PCNA immunohistochemical staining was performed on 4 !-tm thick deparaffinized sections mounted on sialinized slides using the peroxidase antiperoxidase method. The distributions of PCNA expression in the cysts linings were noted and comparison was made qualitatively and quantitatively. PCNA labelling index was used for the quantitative assessment. The results showed that PCNA staining was distributed in the basal and supra basal cells for radicular cysts, dentigerous cysts, and OKCs. PCNA labelling index was highest in OKC (22.33±4.07). The high PCNA labelling index in OKC is indicative of high proliferative activity thus supporting previous reports of OKC as the most aggressive type of odontogenic cysts.
    Matched MeSH terms: Paraffin
  8. Mohd. Ridah L.J., Ismail A., A. Talib N., Muhammad N., Hussain F.A., Zainuddin N.
    MyJurnal
    Introduction: Methylation of promoter region of p16 leading to gene silencing has been implicated ina wide range of malignancies including lymphomas. In diffuse large B cell lymphoma (DLBCL) particularly, a varying percentage of epigenetic inactivation of p16 promoter region was observed ranging from 16 -54%. However, quantitative analysis of p16 promoter methylation in DLBCL has not been extensively studied in Malaysia. Objective: This study aims to quantitatively analyse p16 methylation in DLBCL samples using pyrosequencing technique. Methods: Genomic DNA was extracted from 16 formalin-fixed paraffin-embedded lymphoma tissue blocks from patients diagnosed with DLBCL. Samples were retrieved from Hospital Tengku Ampuan Afzan, Pahang and Hospital Universiti Sains Malaysia, Kelantan. Primers were designed to amplify bisulfite-treated DNA targeting p16 promoter region. Methylation status of 7 CpG sites was determined by pyrosequencing. Results: All the 16 samples studied showed promoter methylation of p16. The range of mean methylation percentage was between 18 to 81%. Conclusion: The present study has successfully measured the level of methylation of p16 in all 7 CpG sites despite the limitation in sample size. Since p16 methylation is a common event in our series of DLBCL cases, it is worth including a larger sample size in future studies to increase the chance of finding a significant correlation with clinical parameters.
    Matched MeSH terms: Paraffin Embedding
  9. Norafiza Zainuddin, Lailatul Jalilah Mohd Ridah, Aqilah Nabihah Omar, Norlelawati A. Talib, Naznin Muhammad, Faezahtul Arbaeyah Hussain
    MyJurnal
    MGMT (O6
    -Methylguanine-DNA Methyltransferase) suppresses tumor development by removing alkyl adduct, while
    SPOCK2 (SPARC/Osteonectin CWCV and Kazal-like domains proteoglycan) abolishes the inhibition of membrane-type
    matrix metalloproteinases (MT-MMP) which leads to angiogenesis. Hence, MGMT methylation may initiate malignant cells
    transformation. In contrast, SPOCK2 methylation is hypothesized not to be a common event in diffuse large B-cell lymphoma
    (DLBCL). In this study, we examined the methylation status of MGMT and SPOCK2 in DLBCL as in Malaysia the information
    is extremely lacking. A total of 88 formalin-fixed paraffin-embedded tissue of patients diagnosed with DLBCL from the
    year 2006 to 2013 were retrieved from Hospital Universiti Sains Malaysia, Kelantan and Hospital Tengku Ampuan Afzan,
    Pahang. Methylation-specific polymerase chain reaction (MSP) was used to examine the methylation status of both genes.
    Interestingly, methylation of MGMT was detected in all the 88 DLBCL samples, whereas SPOCK2 was found to be methylated
    in 83 of 88 (94.3%) DLBCL cases. Our study showed a remarkably high percentage of promoter methylation of both
    MGMT and SPOCK2 genes. Our finding also negates initial expectation that SPOCK2 methylation would be an uncommon
    event in the majority of DLBCL cases. This study has shown a very high percentage of promoter methylation of MGMT and
    SPOCK2 in the DLBCL cases studied by MSP, using archival lymphoma tissues. Nonetheless, additional research is needed
    to quantitatively evaluate MGMT and SPOCK2 methylation, and to analyse gene expression and/or protein expression in
    order to further understand the role of MGMT and SPOCK2 methylation in the pathogenesis of DLBCL.
    Matched MeSH terms: Paraffin Embedding
  10. Samiei G, Yip WK, Leong PP, Jabar MF, Dusa NM, Mohtarrudin N, et al.
    J Cancer Res Ther, 2018 Jun;14(Supplement):S299-S305.
    PMID: 29970680 DOI: 10.4103/0973-1482.235345
    Background: Interleukin (IL)-17A and IL-17F are inflammatory cytokines mainly produced by T helper 17 cells. IL-17A is known to be protumorigenic while IL-17F has a protective role in cancer. A number of studies have been conducted to determine the association between polymorphisms of IL-17AG197A (rs2275913) and IL-17FA7488G (rs763780) and risk of cancers. No studies have yet to be conducted to genotype the IL-17AG197A polymorphism in colorectal cancer (CRC).

    Objective: To assess the association of IL-17AG197A and IL-17FA7488G polymorphisms with CRC risk.

    Materials and Methods: We performed the genotyping by polymerase chain reaction-restriction fragment length polymorphism method on blood samples from 80 healthy individuals and paraffin-embedded tumor tissues from 70 CRC patients.

    Results: Our study showed that IL-17A197AA genotype was significantly associated with an increased CRC risk with odds ratios of 6.08 (95% confidence interval [CI]: 2.25-16.42, P < 0.001) and 2.80 (95% CI: 1.23-6.35, P = 0.014), in comparison with GG and AG genotypes, respectively. However, IL-17FA7488G polymorphism was not significantly associated with CRC risk (P = 0.102). No significant association of IL-17AG197A and IL-17FA7488G polymorphisms with patient and tumor variables was found.

    Conclusion: This report from Malaysia shows the relationship of IL-17A197AA genotype with susceptibility to CRC.

    Matched MeSH terms: Paraffin Embedding
  11. Chew BS, Ghazali R, Othman H, Ismail NAM, Othman AS, Laim NMST, et al.
    J Obstet Gynaecol Res, 2018 Oct 10.
    PMID: 30306675 DOI: 10.1111/jog.13836
    AIM: The aim of our study was to determine the endocan-1 expression in placenta of hypertensive women, and its association with maternal and fetal outcomes.

    METHODS: This was a cross-sectional study consisted of 21 pregnant women with hypertension and 23 without hypertension. The gestational age ranged from 28 to 39 weeks (hypertensive) and 32 to 40 weeks (normotensive). The paraffin embedded formalin fixed placenta tissue blocks were retrieved from the pathology archives. Endocan immunohistochemistry was performed on tissue sections of full thickness and maternal surface of the placenta. The endocan expression was determined in fetal endothelial cells, maternal endothelial cells, cytotrophoblasts, syncytiotrophoblasts and decidual cells. The differences in endocan expression in placenta between hypertensive and normotensive subjects were evaluated by Pearson chi-square test and t-test were used in the statistical analysis.

    RESULTS: The endocan expression was significantly higher in fetal endothelial cells (P

    Matched MeSH terms: Paraffin Embedding
  12. Cheah PL, Li J, Looi LM, Teoh KH, Ong DB, Arends MJ
    PeerJ, 2018;6:e5530.
    PMID: 30221090 DOI: 10.7717/peerj.5530
    Background: Except for a few studies with contradictory observations, information is lacking on the possibility of association between DNA mismatch repair (MMR) status and the presence of cancer stem cells in colorectal carcinoma (CRC), two important aspects in colorectal carcinogenesis.

    Methods: Eighty (40 right-sided and 40 left-sided) formalin-fixed, paraffin-embedded primary CRC were immunohistochemically studied for CD133, a putative CRC stem cell marker, and MMR proteins MLH1, MSH2, MSH6 and PMS2. CD133 expression was semi-quantitated for proportion of tumor immunopositivity on a scale of 0-5 and staining intensity on a scale of 0-3 with a final score (units) being the product of proportion and intensity of tumor staining. The tumor was considered immunopositive only when the tumor demonstrated moderate to strong intensity of CD133 staining (a decision made after analysis of CD133 expression in normal colon). Deficient MMR (dMMR) was interpreted as unequivocal loss of tumor nuclear staining for any MMR protein despite immunoreactivity in the internal positive controls.

    Results: CD133 was expressed in 36 (90.0%) left-sided and 28 (70.0%) right-sided tumors (p  0.05).

    Conclusion: Proficient MMR correlated with high levels of CD133-marked putative cancer stem cells in both right- and left-sided tumors, whereas significantly lower levels of CD133-marked putative cancer stem cells were associated with deficient MMR status in colorectal carcinomas found on the right.

    Matched MeSH terms: Paraffin Embedding
  13. Nenny Noorina Saaid, Reena Rahayu Md Zin, Siti Aishah Md Ali, Sharifah Noor Akmal Syed Hussain, Zulkifli Zainuddin, Zubaidah Zakaria
    Sains Malaysiana, 2014;43:1317-1326.
    The identification of chromosomal aberrations in prostate cancer has been widely studied with several known oncogenes and tumor suppressor genes have successfully been discovered. The most frequent aberrations detected in western population were losses in chromosome 5q, 6q, 8p, 13q, 16q, 17p, 18q and gains of 7p/q and 8q. The purpose of this study was to determine the chromosomal aberrations among Malaysian men of Southeast Asia population and discover those potential genes within that chromosomal aberrant region. Thirty-six formalin-fixed paraffin embedded specimens consist of eight organ-confined prostate cancer cases, five with capsular invasion, 14 showed metastasis and nine cases had no tumor stage recorded, were analyzed by array CGH technique. Chromosomal losses were frequently detected at 4q, 6q, 8p, 13q, 18q while gains at 7q, 11q, 12p, 16q and 17q. Gain of 16q24.3 was statistically significant with tumor size. Gains of 6q25.1 and Xq12 as well as losses of 3p13-p1.2 and 13q33.1-q33.3 were significantly correlated with Gleason grade whereas 12p13.31 gain was associated with bone metastasis. Several potential genes have also been found within that aberrant region which is myopodin (4q26-q27), ROBO1 (3p13-p11.2), ERCC5 (13q33.1-q33.3) and CD9 (12p13.31), suggesting that these genes may play a role in prostate cancer progression. The chromosomal aberrations identified by array CGH analysis could provide important clues to discover potential genes associated with prostate tumorigenesis of Malaysian men.
    Matched MeSH terms: Paraffin Embedding
  14. Mohd Rohaizad Md Roduan, Norhafizah Mohtarrudin, Chong PP, Malina Osman, Noraini Mohd Dusa
    Sains Malaysiana, 2015;44:727-733.
    Inflammation plays an important role to the process of prostate carcinogenesis by increasing the rate of cell proliferation,
    which contributes to an aggressive tumour phenotype. Cyclooxygenase-2 (COX-2) has been found overexpressed in
    various types of cancer cells including prostate. The aim of this study was to investigate the COX-2 expressions in different
    types of human prostate tissues. Paraffin-embedded prostate tissues from 263 samples were examined for the expression
    of COX-2 marker by immunohistochemistry method. COX-2 was found highly expressed in prostate adenocarcinoma
    (p=0.001) as compared to benign and normal tissues. The score of COX-2 expressions in most of normal prostate was
    weak 49 (77.8%), while only 16 (16%) of BPH showed strong expression. 56 cases (56%) prostate cancer showed strong
    COX-2 expression. Prostate cancer cases showed significant differences in staining patterns as tumour grade increased.
    In addition, COX-2 expression was significantly correlated with Gleason score in cancerous tissues. This study suggests
    that COX-2 overexpression is associated with prostate cancer and higher grade tumour.
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  15. Ploetz RC, Palmateer AJ, Geiser DM, Juba JH
    Plant Dis, 2007 May;91(5):639.
    PMID: 30780734 DOI: 10.1094/PDIS-91-5-0639A
    Roselle, Hibiscus sabdariffa var. sabdariffa, is an annual that is grown primarily for its inflated calyx, which is used for drinks and jellies. It is native from India to Malaysia, but was taken at an early date to Africa and is now widely grown in the tropics and subtropics (2). In late 2005, dying plants were noted by a producer in South Florida. Plants wilted, became chlorotic, and developed generally unthrifty, sparse canopies. Internally, conspicuous vascular discoloration was evident in these plants from the roots into the canopy. After 5 days on one-half-strength potato dextrose agar (PDA), salmon-colored fungal colonies grew almost exclusively from surface-disinfested 5 mm2 pieces of vascular tissue. On banana leaf agar, single-spored strains produced the following microscopic characters of Fusarium oxysporum: copious microconidia on monophialides, infrequent falcate macroconidia, and terminal and intercalary chlamydospores. Partial, elongation factor 1-α (EF1-α) sequences were generated for two of the strains, O-2424 and O-2425, and compared with previously reported sequences for the gene (3). Maximum parsimony analysis of sequences showed that both strains fell in a large, previously described clade of the F. oxysporum complex (FOC) that contained strains from agricultural hosts, as well as human clinical specimens (2; clade 3 in Fig. 4); many of the strains in this clade have identical EF1-α sequences. Strains of F. oxysporum recovered from wilted roselle in Egypt, O-647 and O-648 in the Fusarium Research Center collection, were distantly related to the Florida strains. We are not aware of other strains of F. oxysporum from roselle in other international culture collections. Roselle seedlings were inoculated with O-2424 and O-2425 by placing a mycelial plug (5 mm2, PDA) over a small incision 5 cm above the soil line and then covering the site with Parafilm. Parafilm was removed after 1 week, and plants were incubated under ambient temperatures (20 to 32°C) in full sun for an additional 5 weeks (experiment 1) or 7 weeks (experiment 2). Compared with mock-inoculated (wound + Parafilm) control plants, both O-2424 and O-2425 caused significant (P < 0.05) vascular disease (linear extension of discolored xylem above and below wound site) and wilting (subjective 1 to 5 scale); both isolates were recovered from affected plants. F. oxysporum-induced wilt of roselle has been reported in Nigeria (1) and Malaysia (4) where the subspecific epithet f. sp. rosellae was used for the pathogen. We are not aware of reports of this disease elsewhere. To our knowledge, this is the first report of F. oxysporum-induced wilt of roselle in the United States. Research to determine whether the closely related strains in clade 3 of the FOC are generalist plant pathogens (i.e., not formae speciales) is warranted. References: (1) N. A. Amusa et al. Plant Pathol. J. 4:122, 2005. (2) J. Morton. Pages 81-286 in: Fruits of Warm Climates. Creative Resource Systems, Inc., Winterville, NC, 1987. (3) K. O'Donnell et al. J. Clin. Microbiol. 42:5109, 2004. (4) K. H. Ooi and B. Salleh. Biotropia 12:31, 1999.
    Matched MeSH terms: Paraffin
  16. Choi IY
    Plant Dis, 2011 Feb;95(2):227.
    PMID: 30743439 DOI: 10.1094/PDIS-05-10-0371
    This study was conducted to identify the causal organism of bark dieback disease of highbush blueberry (Vaccinium corymbosum L.) observed in Korea. Blueberry, a woody plant that is native to North America, belongs to the family Ericaceae and genus Vaccinium. Of the 400 species of blueberry in the world, most are distributed in the tropics of Malaysia and Southeast Asia. Highbush blueberry is abundantly grown in Canada and the United States and has become a popular commercial crop in Korea for products such as jam, wine, and sauce. Bark dieback disease of blueberry was found in Sunchang (<5% incidence), Jeollabuk-do, Korea in July 2009. Typical symptoms of the disease were blight and dieback on the stems with lesions extending along entire branches. Morphological examination revealed that the perithecia were of the globose type with a nipple, 155 to 490 (374.6) μm, and brown on the dead bark. Asci were bitunicate and clavate or cylindrical with dimensions of 63 to 125 × 16 to 20 μm and containing eight ascospores. Ascospores were of the long ovoid type with dimensions of 13.2 to 23.7 (17.98) × 25.4 to 41.1 (33.21) μm. From extracted genomic DNA, the internal transcribed spacer (ITS)-5.8S ribosomal DNA region was amplified with universal primers ITS1 (5'-TCCGTAGGTGAACCTGCGG-3') and ITS4 (5'-TCCTCCGCTTATTGATATGC-3'). A BLAST search of GenBank with the ITS sequence revealed that the Sunchang isolate (GenBank Accession No. HQ384217) had 99 to 100% sequence identity with the following Botryosphaeria dothidea accessions: FJ517657, AJ938005, FJ478129, FJ171723, and AJ938004. Phylogenetic analysis with the Sunchang isolate, B. dothidea strains, and related species revealed that the B. dothidea isolate and strains comprised a monophyletic group distinguished from other Botryosphaeria spp. including B. ribis, B. parva, B. protearum, B. lutea, B. australis, B. rhodina, B. obtuse, and B. stevensii (2). On the basis of morphological and molecular results, the isolate was identified as B. dothidea (Moug.) Ces. & De Not. A culture of B. dothidea isolate was grown on potato dextrose agar (PDA) for 10 days. A 5-mm plug was inoculated into stem wounds created with a No. 2 cork borer in 20 2-year-old disease-free blueberry plants grown in a greenhouse. Six plants inoculated with only PDA plugs served as noninoculated controls. The wounds were covered with Parafilm. After 3 months, the Parafilm was removed and black lesions were observed at the fungal inoculation sites, while no lesion was observed on the control plants. To complete Koch's postulates, the fungus was reisolated from the lesions and confirmed to be B. Dothidea (1). There is an urgent need to determine the spread of this disease in Korea, estimate the losses, and develop methods for reducing damage through biological and eco-friendly cultural control methods. References: (1) D. Jurc et al. Plant Pathol. 55:299, 2006. (2) B. Slippers et al. Mycologia 96:83, 2004.
    Matched MeSH terms: Paraffin
  17. Sulaiman R, Thanarajoo SS, Kadir J, Vadamalai G
    Plant Dis, 2012 May;96(5):767.
    PMID: 30727556 DOI: 10.1094/PDIS-06-11-0482-PDN
    Physic nut (Jatropha curcas L.) is an important biofuel crop worldwide. Although it has been reported to be resistant to pests and diseases (1), stem cankers have been observed on this plant at several locations in Peninsular Malaysia since early February 2008. Necrotic lesions on branches appear as scars with vascular discoloration in the tissue below the lesion. The affected area is brownish and sunken in appearance. Disease incidence of these symptomatic nonwoody plants can reach up to 80% in a plantation. Forty-eight samples of symptomatic branches collected from six locations (University Farm, Setiu, Gemenceh, Pulau Carey, Port Dickson, and Kuala Selangor) were surface sterilized in 10% bleach, rinsed twice with sterile distilled water, air dried on filter paper, and plated on water agar. After 4 days, fungal colonies on the agar were transferred to potato dextrose agar (PDA) and incubated at 25°C. Twenty-seven single-spore fungal cultures obtained from all locations produced white, aerial mycelium that became dull gray after a week in culture. Pycnidia from 30-day-old pure cultures produced dark brown, oval conidia that were two celled, thin walled, and oval shape with longitudinal striations. The average size of the conidia was 23.63 × 12.72 μm with a length/width ratio of 1.86. On the basis of conidial morphology, these cultures were identified as Lasiodiplodia theobromae. To confirm the identity of the isolates, the internal transcribed spacer (ITS) region was amplified with ITS1/ITS4 primers and sequenced. The sequences were deposited in GenBank (Accession Nos. HM466951, HM466953, HM466957, GU228527, HM466959, and GU219983). Sequences from the 27 isolates were 99 to 100% identical to two L. theobromae accessions in GenBank (Nos. HM008598 and HM999905). Hence, both morphological and molecular characteristics confirmed the isolates as L. theobromae. Pathogenicity tests were performed in the glasshouse with 2-month-old J. curcas seedlings. Each plant was wound inoculated by removing the bark on a branch to a depth of 2 mm with a 10-mm cork borer. Inoculation was conducted by inserting a 10-mm-diameter PDA plug of mycelium into the wound and wrapping the inoculation site with wetted, cotton wool and Parafilm. Control plants were treated with plugs of sterile PDA. Each isolate had four replicates and two controls. After 6 days of incubation, all inoculated plants produced sunken, necrotic lesions with vascular discoloration. Leaves were wilted and yellow above the point of inoculation on branches. The control plants remained symptomless. The pathogen was successfully reisolated from lesions on inoculated branches. L. theobromae has been reported to cause cankers and dieback in a wide range of hosts and is common in tropical and subtropical regions of the world (2,3). To our knowledge, this is the first report of stem canker associated with L. theobromae on J. curcas in Malaysia. References: (1) S. Chitra and S. K. Dhyani. Curr. Sci. 91:162, 2006. (2) S. Mohali et al. For. Pathol. 35:385, 2005. (3) E. Punithalingam. Page 519 in: CMI Descriptions of Pathogenic Fungi and Bacteria. Commonwealth Mycological Institute, Kew, Surrey, UK. 1976.
    Matched MeSH terms: Paraffin
  18. Hao, Lim Zhen, Hikmat Said Al-Salim, Norida Ridzuan
    MyJurnal
    The continuous depletion of global oil reserves with the propensity for light distillates
    propels the oil and gas industry to explore heavier fractions of crude oils with significant
    amount of paraffin waxes. However, the precipitation and deposition of waxes during the
    transportation of these waxy crude oils in the pipelines contribute to several issues, such as
    the flowability reduction, excessive pumping cost, and wax gel formation, that adversely
    affect the supposedly steady offshore oil production. As a result, substantial resources are
    expended to resolve these flow assurance problems. The wax inhibitors and pour point
    depressants are developed and modified to meet the wax remediation criteria. Essentially,
    the wax crystals are formed through the nucleation, growth, and agglomeration processes,
    while the deposition of these waxes occurs via molecular diffusion and shear dispersion.
    The wax inhibitors are able to control the growth of wax crystals through nucleation, cocrystallization,
    adsorption, and dispersion interactions. This paper particularly assessed
    the following compounds: (1) polymeric wax inhibitors, (2) nano-hybrid pour point
    depressants, (3) organic solvents, and
    (4) surfactants. Given the significance of
    these compounds in the deposition and
    precipitation of waxes, it is imperative to
    comprehensively explore the types and
    nature of these compounds and their recent
    applications as well as to critically assess
    their strengths and drawbacks, which were
    addressed in this paper. Furthermore, the
    challenges of using these compounds and the factors that govern their efficiencies were also discussed. Accordingly, the carbon
    length and the molecular weight of both paraffin waxes and wax inhibitors are among the
    most influential factors.
    Matched MeSH terms: Paraffin
  19. Silakhori M, Naghavi MS, Metselaar HSC, Mahlia TMI, Fauzi H, Mehrali M
    Materials (Basel), 2013 Apr 29;6(5):1608-1620.
    PMID: 28809232 DOI: 10.3390/ma6051608
    Microencapsulated paraffin wax/polyaniline was prepared using a simple in situ polymerization technique, and its performance characteristics were investigated. Weight losses of samples were determined by Thermal Gravimetry Analysis (TGA). The microencapsulated samples with 23% and 49% paraffin showed less decomposition after 330 °C than with higher percentage of paraffin. These samples were then subjected to a thermal cycling test. Thermal properties of microencapsulated paraffin wax were evaluated by Differential Scanning Calorimeter (DSC). Structure stability and compatibility of core and coating materials were also tested by Fourier transform infrared spectrophotometer (FTIR), and the surface morphology of the samples are shown by Field Emission Scanning Electron Microscopy (FESEM). It has been found that the microencapsulated paraffin waxes show little change in the latent heat of fusion and melting temperature after one thousand thermal recycles. Besides, the chemical characteristics and structural profile remained constant after one thousand thermal cycling tests. Therefore, microencapsulated paraffin wax/polyaniline is a stable material that can be used for thermal energy storage systems.
    Matched MeSH terms: Paraffin
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