Displaying publications 81 - 100 of 222 in total

Abstract:
Sort:
  1. Fulltext Exploring the molecular pathogenesis, diagnosis and treatment of fibrolamellar hepatocellular carcinoma: A state of art review of the current literature
    Alshareefy Y, Shen CY, Prekash RJ
    Pathol Res Pract, 2023 Aug;248:154655.
    PMID: 37429175 DOI: 10.1016/j.prp.2023.154655
    This paper aims to present a detailed overview of fibrolamellar carcinoma (FLC), a variant of hepatocellular carcinoma (HCC) that accounts for approximately 1-9% of all cases a. according to the SEER database. Despite ongoing research, the aetiology of FLC tumours remains unclear. Nevertheless, FLC is believed to have a better overall prognosis than other primary liver tumours, such as hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma. This study aims to present a comprehensive overview of fibrolamellar carcinoma (FLC), with a focus on its epidemiology, pathogenesis, diagnosis, treatment, and prognosis. FLC frequently incorporate features of stomach pain, weight loss, and malaise in their clinical signs and symptoms, which are generally nonspecific Ultimately, the most common physical finding is an abdominal mass or hepatomegaly. With this said, several unusual presentations have been documented such as Budd Chiari syndrome, severe anaemia, non-bacterial thrombotic endocarditis and many more. In regards to this tumour's genetic analysis, it is characterised by a 400 kb deletion on chromosome 19 leading to a functional DNAJB1-PRKACA chimeric transcript in addition to tetraploidy in 50% of cases. FLC is chromosomally stable as compared to typical HCC. mTOR pathway activation has also been found to play a critical role in 47% of these tumours and EFGR over-expression is also evident. Fibrolamellar carcinomas (FLCs) exhibit a distinctive gross appearance, characterized by a yellow to pale tan colour, with a consistency that can vary from soft to firm and hard. In addition, a central scar is observed in 60-70% of FLC cases. The central scar is typically white or grey in colour and has a fibrous appearance, which is often surrounded by nodular, tumour-like tissue. Its histologic appearance is characterized by large polygonal cells with abundant eosinophilic cytoplasm, large vesiculated nuclei, large nucleoli, and arranged in lamellar bands of collagen fibres. Lamellar bands of fibrosis, consisting of collagen type I, III and IV, have also been identified as a distinctive histologic feature that is observed under low power magnification. Ultrasound, CT and MRI along with image guided biopsy are the primary modalities in diagnosis. Current management options include systemic therapy which has thus far been unremarkable with platinum-based therapies as well combination therapy with interferon alpha-2b being the most successful options. Surgical resection remains the primary treatment modality and there have been no advances in targeted therapies. Although the prognosis for FLC is favourable as compared to other hepatic cancer subtypes such as intrahepatic cholangiocarcinoma, there is a high rate of recurrence ranging from 33% to 100% with a median recurrence-free survival of 20-48 months. As a result of this there is a low overall cure rate associated with this tumour type and much more research is required to gain an in-depth understanding of the molecular mechanisms occurring in order to provide more adequate treatment to patients who suffer from this condition.
    Matched MeSH terms: HSP40 Heat-Shock Proteins
  2. Impact of heat stress on health-related symptoms and physiological changes among workers at a palm oil mill in Mukah, Sarawak, Malaysia
    Vallennie V, Isa SNI, Mazlan AZ, Shaifuddin SNM
    Med J Malaysia, 2024 Mar;79(Suppl 1):82-87.
    PMID: 38555890
    INTRODUCTION: The palm oil (PO) industry is one of the most important sectors in the Malaysian economy. Workers at PO mills are, however, at risk for a number of health and safety issues, including heat stress, as the PO is one of the industries with high heat exposure. Heat stress occurs when a person's body cannot get rid of excess heat. Heat stress can result in heat cramps, heat exhaustion, heat rash, and heat stroke. It also results in physiological and psychological changes that can have an impact on a worker's performance. Therefore, this study aimed to evaluate the impact of heat stress on health-related symptoms and physiological changes among workers in a PO mill.

    MATERIALS AND METHODS: This cross-sectional study was conducted in a PO mill located in Mukah, Sarawak, Malaysia. Thirty-one workers from the four workstations (sterilizer, boiler, oil, and engine rooms) were selected as the respondents in this study. Wet Bulb Globe Thermometer was used in this study to measure the environmental temperature (WBGTin). Body core temperature (BCT), blood pressure (BP), and heart rate (HR) were recorded both before and after working in order to assess the physiological effects of heat stress on workers. A set of questionnaires were used to determine sociodemographic characteristics of the respondents and their symptoms related to heat stress. Data were then analyzed using SPSS Ver28.

    RESULTS: The WBGTin was found to be above the ACGIH threshold limit value of heat stress exposure in the engine room, sterilizer, and boiler workstations (>28.0°C). Additionally, there was a significant difference in the worker's BCT in these three workstations before and after work (p<0.05). Only the systolic BP and HR of those working at the boiler workstation showed significant difference between before and after work (p<0.05). The most typical symptoms that workers experience as a result of being exposed to heat at work include headache and fatigue. However, statistical analysis using Spearman Rho's test showed that there is no correlation between heat stress level with physiological changes and health-related symptoms among study respondents (p>0.05).

    CONCLUSION: Results of the present study confirmed that workers in PO mill were exposed to high temperatures while at work. Although the evidence indicates the physiological parameters in general are not significantly affected while working, it also demonstrated that worker's body adapts and acclimates to the level of heat. Even so, precautions should still be taken to reduce future heat exposure. It is recommended that a physiological study be carried out that focuses on cognitive function impairment to support the evidence regarding the effects of heat stress on PO mill workers.

    Matched MeSH terms: Heat-Shock Response
  3. Differential Gene Expression of Heat Shock Protein 90 (Hsp90) of Candida albicans obtained from Malaysian and Iranian Patients
    Khalili V, Shokri H, Md Akim A, Khosravi AR
    Malays J Med Sci, 2016 May;23(3):64-71.
    PMID: 27418871
    Candida albicans (C. albicans) has several virulence factors, in particular heat shock protein 90 (Hsp90), which is expressed by Hsp90 gene. The purposes of this study were to assess the expression of Hsp90 gene in clinical and control isolates of C. albicans obtained from different geographical regions (Malaysia and Iran), different temperatures (25°C, 37°C and 42°C) and mice with candidiasis.
    Matched MeSH terms: HSP90 Heat-Shock Proteins
  4. Environmental temperature and stocking density effects on acute phase proteins, heat shock protein 70, circulating corticosterone and performance in broiler chickens
    Najafi P, Zulkifli I, Jajuli NA, Farjam AS, Ramiah SK, Amir AA, et al.
    Int J Biometeorol, 2015 Nov;59(11):1577-83.
    PMID: 25649005 DOI: 10.1007/s00484-015-0964-3
    An experiment was conducted to determine the effect of different stocking densities on serum corticosterone (CORT), ovotransferrin (OVT), α1-acid glycoprotein (AGP) and ceruloplasmin (CP) concentrations, brain heat shock protein (HSP) 70 expression and performance in broiler chickens exposed to unheated and heated conditions. Day-old chicks were stocked at 0.100 m(2)/bird (low density (LD)) or 0.063 m(2)/bird (high density (HD)), in battery cages and housed in environmentally controlled rooms. From 21 to 35 days of age, birds from each stocking density group were exposed to either 24 or 32 °C. Growth performance was recorded during the heat treatment period, and blood and brain samples were collected to determine CORT, OVT, AGP, CP and HSP 70 levels on day 35. Heat treatment but not stocking density was detrimental to growth performance. There were significant temperature × density interactions for CORT, CP and OVT on day 35. Although HD elevated CORT, CP and OVT when compared to LD, the effects of the former were more obvious under heated condition. Both temperature and density had significant effect on AGP and HSP 70. In conclusion, irrespective of temperature, high stocking density was physiologically stressful to broiler chickens, as indicated by CORT, AGP, CP, OVT and HSP 70, but not detrimental to growth performance and survivability. As it was shown in the present study, AGP, CP and OVT could be useful biomarkers to determine the effect of overcrowding and high temperature on the welfare of broiler chickens.
    Matched MeSH terms: HSP70 Heat-Shock Proteins/metabolism*
  5. Fulltext Value of Shock Index in prognosticating the short-term outcome of death for patients presenting with severe sepsis and septic shock in the emergency department
    Yussof SJM, Zakaria MI, Mohamed FL, Bujang MA, Lakshmanan S, Asaari AH
    Med J Malaysia, 2012 Aug;67(4):406-11.
    PMID: 23082451
    INTRODUCTION: The importance of early recognition and treatment of sepsis and its effects on short-term survival outcome have long been recognized. Having reliable indicators and markers that would help prognosticate the survival of these patients is invaluable and would subsequently assist in the course of effective dynamic triaging and goal directed management.
    STUDY OBJECTIVES: To determine the prognosticative value of Shock Index (SI), taken upon arrival to the emergency department and after 2 hours of resuscitation on the shortterm outcome of severe sepsis and septic shock patients.
    METHODOLOGY: This is a retrospective observational study involving 50 patients admitted to the University of Malaya Medical Centre between June 2009 and June 2010 who have been diagnosed with either severe sepsis or septic shock. Patients were identified retrospectively from the details recorded in the registration book of the resuscitation room. 50 patients were selected for this pilot study. The population comprised 19 males (38%) and 31 females (62%). The median (min, max) age was 54.5 (17.0, 84.0) years. The number of severe sepsis and septic shock cases were 31 (62%), and 19 (38%) respectively. There were 17 (34%) cases of pneumonias, 13 (26%) cases of urological sepsis, 8 (16%) cases of gastro intestinal tract related infections and 12 (24%) cases of other infections. There were a total of 23 (46%) survivors and 27 (54%) deaths. The value of the shock index is defined as systolic blood pressure divided by heart rate was calculated. Shock Index on presentation to ED (SI 1) and after 2 hours of resuscitation in the ED (SI 2). The median, minimum and maximum variables were tested using Mann-Whitney U and Chi square analysis. The significant parameters were re-evaluated for sensitivity, specificity and cut-off points. ROC curves and AUC values were generated among these variables to assess prognostic utility for outcome.
    RESULTS: Amongst all 7 variables tested, 2 were tested to be significant (p: < 0.05). From the sensitivity, specificity and ROC analysis, the best predictor for death was (SI 2) with a sensitivity of 80.8%, specificity of 79.2%, AUC value of 0.8894 [CI 95 0.8052, 0.9736] at a cut-off point of > or = 1.0.
    CONCLUSION: (SI 2) may potentially be utilized as a reliable predictor for death in patients presenting with septic shock and severe sepsis in an emergency department. This parameters should be further analyzed in a larger scale prospective study to determine its validity.
    Matched MeSH terms: Shock, Septic/physiopathology
  6. Pulmonary edema of an unexpected cause
    Abdullah HN, Khairina WW
    South. Med. J., 2008 Oct;101(10):1035-7.
    PMID: 18791521 DOI: 10.1097/SMJ.0b013e31817fbeb8
    Atrial myxoma is rarely seen in practice. We report a 67-year-old female who presented with acute cardiac insufficiency and pulmonary edema. Cardiac murmur was not detected on precordial examination. Urgent echocardiography, however, revealed atrial myxoma causing mitral valve obstruction. We point out that a normal cardiac examination does not exclude atrial myxoma. The diagnosis may be delayed until significant myocardial dysfunction occurs, as reported here. The clinical presentation of cardiac myxoma is discussed, along with appropriate investigations and treatment.
    Matched MeSH terms: Shock, Cardiogenic/etiology
  7. Fulltext Extra-corporeal shock-wave therapy in the treatment of non-unions
    Chooi YS, Penafort R
    Med J Malaysia, 2004 Dec;59(5):674-7.
    PMID: 15889572
    It has been at least a decade since the introduction of extra-corporeal shock-wave treatment (ESWT) for the treatment of non-unions. Despite conflicting opinions in the literature, it is recently experiencing a revival. This paper reports our experience with Ossa Tron, which produces shock-waves electro-hydraulically, on 5 patients. The two successful cases experienced remarkable results of union at an average of 22 weeks after ESWT. The remaining three had disappointing results. A description of the study and a note on the essential issues are presented.
    Matched MeSH terms: High-Energy Shock Waves/therapeutic use*
  8. Ingestion of food pellets containing Escherichia coli overexpressing the heat-shock protein DnaK protects Penaeus vannamei (Boone) against Vibrio harveyi (Baumann) infection
    Sinnasamy S, Noordin NM, MacRae TH, Bin Abdullah MI, Bossier P, Wahid ME, et al.
    J Fish Dis, 2016 May;39(5):577-84.
    PMID: 26132358 DOI: 10.1111/jfd.12390
    Feeding aquatic animals with bacterial encapsulated heat-shock proteins (Hsps) is potentially a new method to combat vibriosis, an important disease affecting aquatic animals used in aquaculture. Food pellets comprised of shrimp and containing Escherichia coli overexpressing either DnaK-DnaJ-GrpE, the prokaryotic equivalents of Hsp70-Hsp40-Hsp20, or only DnaK were fed to juveniles of the white leg shrimp Penaeus vannamei, and protection against pathogenic Vibrio harveyi was determined. Maintaining pellets at different temperatures for varying lengths of time reduced the number of live adhering E. coli, as did contact with sea water, demonstrating that storage and immersion adversely affected bacterial survival and attachment to pellets. Feeding P. vannamei with E. coli did not compromise their survival, indicating that the bacteria were not pathogenic to shrimp. Feeding P. vannamei with pellets containing bacteria overproducing DnaK (approximately 60 cells g(-1) pellets) boosted P. vannamei survival twofold against V. harveyi, suggesting that DnaK plays a role in Vibrio tolerance. Pellets containing DnaK were effective in providing protection to P. vannamei for up to 2 weeks before loss of viability and that DnaK encapsulated by these bacteria enhanced shrimp resistance against Vibrio infection.
    Matched MeSH terms: HSP70 Heat-Shock Proteins/genetics*
  9. Diaphragmatic hernia: an unusual cause of postpartum collapse
    Sharifah H, Naidu A, Vimal K
    BJOG, 2003 Jul;110(7):701-3.
    PMID: 12842063
    Matched MeSH terms: Shock/etiology
  10. Fulltext Renal trauma: a local experience
    Mack POP, Ng HN
    Med J Malaysia, 1985 Dec;40(4):312-6.
    PMID: 3842731
    40 cases of major renal trauma over a period of five years in a peripheral hospital in Singapore were reviewed. 90% were due to blunt trauma with motor-cycle accidents forming the majority. There were five cases of superficial cortical injury, three cases of shattered kidneys, six cases of parenchymal injuries, one case of pedicle injury and one case of combined pedicle and parenchymal injury. Nephrectomy rate was 22.5% in this series. This is felt to be unduly high. Half of all the cases operated upon ended up with an immediate total nephrectomy. There was no mortality in this series. We recommend a more conservative policy of watchful waiting to achieve better chances of organ preservation without increasing mortality.
    Matched MeSH terms: Shock/etiology
  11. Fulltext Nucleotide and encoded amino acid sequences of the capsid protein gene of three dengue-2 viruses isolated in Malaysia from patients with dengue haemorrhagic fever, dengue shock syndrome or dengue fever
    Samuel S, Koh CL, Pang T, Lam SK
    Nucleic Acids Res, 1990 Apr 11;18(7):1904.
    PMID: 2336373
    Matched MeSH terms: Shock, Septic/microbiology
  12. Fulltext Mitragynine, an euphoric compound inhibits hERG1a/1b channel current and upregulates the complexation of hERG1a-Hsp90 in HEK293-hERG1a/1b cells
    Tay YL, Amanah A, Adenan MI, Wahab HA, Tan ML
    Sci Rep, 2019 12 24;9(1):19757.
    PMID: 31874991 DOI: 10.1038/s41598-019-56106-6
    Mitragyna speciosa Korth (M. speciosa) has been widely used as a recreational product, however, there are growing concerns on the abuse potentials and toxicity of the plant. Several poisoning and fatal cases involving kratom and mitragynine have been reported but the underlying causes remain unclear. The human ether-a-go-go-related gene 1 (hERG1) encodes the pore-forming subunit underlying cardiac rapidly delayed rectifier potassium current (IKr). Pharmacological blockade of the IKr can cause acquired long QT syndrome, leading to lethal cardiac arrhythmias. This study aims to elucidate the mechanisms of mitragynine-induced inhibition on hERG1a/1b current. Electrophysiology experiments were carried out using Port-a-Patch system. Quantitative RT-PCR, Western blot analysis, immunofluorescence and co-immunoprecipitation methods were used to determine the effects of mitragynine on hERG1a/1b expression and hERG1-cytosolic chaperones interaction. Mitragynine was found to inhibit the IKr current with an IC50 value of 332.70 nM. It causes a significant reduction of the fully-glycosylated (fg) hERG1a protein expression but upregulates both core-glycosylated (cg) expression and hERG1a-Hsp90 complexes, suggesting possible impaired hERG1a trafficking. In conclusion, mitragynine inhibits hERG1a/1b current through direct channel blockade at lower concentration, but at higher concentration, it upregulates the complexation of hERG1a-Hsp90 which may be inhibitory towards channel trafficking.
    Matched MeSH terms: HSP90 Heat-Shock Proteins/metabolism*
  13. The effect of early-age food restriction on heat shock protein 70 response in heat-stressed female broiler chickens
    Zulkifli I, Che Norma MT, Israf DA, Omar AR
    Br Poult Sci, 2002 Mar;43(1):141-5.
    PMID: 12003331
    1. This study was conducted to determine the effect of early-age food restriction on heat shock protein (hsp) 70 synthesis in the brains of female broiler chickens exposed to high ambient temperatures. 2. Chicks were brooded for 3 weeks and then maintained at 24+/-1 degrees C. 3. On d 0, chicks were assigned to one of 4 feeding regimens; each regimen was applied to 4 cages of chicks. The regimens were: (1) ad libitum feeding (AL); (2) 80% food restriction at 4, 5 and 6 d of age (F80); (3) 60% food restriction at 4, 5, and 6 d of age (F60); and (4) 40% food restriction at 4, 5 and 6 d of age (F40). From d 35 to d 41, all chicks were subjected to 38+/-1 degrees C for 2 h/d. 4. One day following food restriction (d 7), hsp 70 expression in the brain samples of F60 and F40 chicks was augmented but not those fed AL and F80. 5. Prior to the heat challenge (d 35), all chicks had similar hsp 70 response. Irrespective of feeding regimen, there was a marked increase in hsp 70 expression after 4 d of heat treatment (d 38). Following 7 d of heat exposure (d 41), except for the F60 chicks, the augmented hsp 70 expression in the brains of AL, F80 and F40 birds was not maintained. 6. Enhancement of hsp 70 expression was noted in birds subjected to F60, but not AL, F80 or F40, throughout the period of heat exposure.
    Matched MeSH terms: HSP70 Heat-Shock Proteins/biosynthesis*
  14. Fulltext Spontaneous Rupture in a Non-Laboring Uterus at 20 Weeks: A Case Report
    Omar NS, Mat Jin N, Mohd Zahid AZ, Abdullah B
    Am J Case Rep, 2020 Aug 10;21:e924894.
    PMID: 32776917 DOI: 10.12659/AJCR.924894
    BACKGROUND Uterine rupture is uncommon but when it happens, it can cause significant morbidity and mortality to both mother and fetus. Incidence reportedly is higher in scarred than in unscarred uteri. Most cases occur in laboring women in their third trimester with a previous history of uterine surgery, such as caesarean delivery or myomectomy. We present a case of spontaneous uterine rupture in a non-laboring uterus in the mid-trimester of pregnancy. CASE REPORT The patient presented with threatened miscarriage at 17 weeks' gestation and ultrasound findings were that raised suspicion of a morbidly adherent placenta. Her history was significant for two previous cesarean deliveries more than 5 years ago followed by two spontaneous complete miscarriages in the first trimester. The patient was managed conservatively until 20 weeks' gestation, when she presented with acute abdomen with hypotensive shock. Her hemoglobin dropped to a level such that she required blood transfusion. An emergency exploratory laparotomy was performed, which revealed a 5-cm rupture in the lower part of the anterior wall of the uterus, out of which there was extrusion of part of the placenta. Given the patient's massive bleeding, the decision was made to proceed with subtotal hysterectomy. Histopathology of the specimen confirmed the diagnosis of placenta percreta. CONCLUSIONS Identification of uterine scarring with morbidly adherent placenta is crucial because even in early pregnancy, it can lead to uterine rupture. Furthermore, failure to recognize and promptly manage uterine rupture may prove fatal.
    Matched MeSH terms: Shock/etiology
  15. Fulltext Heat alleviation strategies for athletic performance: A review and practitioner guidelines
    Gibson OR, James CA, Mee JA, Willmott AGB, Turner G, Hayes M, et al.
    Temperature (Austin), 2020;7(1):3-36.
    PMID: 32166103 DOI: 10.1080/23328940.2019.1666624
    International competition inevitably presents logistical challenges for athletes. Events such as the Tokyo 2020 Olympic Games require further consideration given historical climate data suggest athletes will experience significant heat stress. Given the expected climate, athletes face major challenges to health and performance. With this in mind, heat alleviation strategies should be a fundamental consideration. This review provides a focused perspective of the relevant literature describing how practitioners can structure male and female athlete preparations for performance in hot, humid conditions. Whilst scientific literature commonly describes experimental work, with a primary focus on maximizing magnitudes of adaptive responses, this may sacrifice ecological validity, particularly for athletes whom must balance logistical considerations aligned with integrating environmental preparation around training, tapering and travel plans. Additionally, opportunities for sophisticated interventions may not be possible in the constrained environment of the athlete village or event arenas. This review therefore takes knowledge gained from robust experimental work, interprets it and provides direction on how practitioners/coaches can optimize their athletes' heat alleviation strategies. This review identifies two distinct heat alleviation themes that should be considered to form an individualized strategy for the athlete to enhance thermoregulatory/performance physiology. First, chronic heat alleviation techniques are outlined, these describe interventions such as heat acclimation, which are implemented pre, during and post-training to prepare for the increased heat stress. Second, acute heat alleviation techniques that are implemented immediately prior to, and sometimes during the event are discussed. Abbreviations: CWI: Cold water immersion; HA: Heat acclimation; HR: Heart rate; HSP: Heat shock protein; HWI: Hot water immersion; LTHA: Long-term heat acclimation; MTHA: Medium-term heat acclimation; ODHA: Once-daily heat acclimation; RH: Relative humidity; RPE: Rating of perceived exertion; STHA: Short-term heat acclimation; TCORE: Core temperature; TDHA: Twice-daily heat acclimation; TS: Thermal sensation; TSKIN: Skin temperature; V̇O2max: Maximal oxygen uptake; WGBT: Wet bulb globe temperature.
    Matched MeSH terms: Heat-Shock Proteins; Heat-Shock Response
  16. "NO LOSS WITHOUT PROFIT" A STUDY IN MATERNAL MORTALITY
    BROWNE AD
    Med J Malaysia, 1963 Jun;17:306-15.
    PMID: 14060509
    Matched MeSH terms: Shock, Hemorrhagic*
  17. Fulltext Severe Plasmodium knowlesi with dengue coinfection
    Che Rahim MJ, Mohammad N, Besari AM, Wan Ghazali WS
    BMJ Case Rep, 2017 Feb 20;2017.
    PMID: 28219910 DOI: 10.1136/bcr-2016-218480
    We report a case of severe Plasmodium knowlesi and dengue coinfection in a previously healthy 59-year-old Malay man who presented with worsening shortness of breath, high-grade fever with chills and rigors, dry cough, myalgia, arthralgia, chest discomfort and poor appetite of 1 week duration. There was a history mosquito fogging around his neighbourhood in his hometown. Further history revealed that he went to a forest in Jeli (northern part of Kelantan) 3 weeks prior to the event. Initially he was treated as severe dengue with plasma leakage complicated with type 1 respiratory failure as evidenced by positive serum NS1-antigen and thrombocytopenia. Blood for malarial parasite (BFMP) was sent for test as there was suspicion of malaria due to persistent thrombocytopenia despite recovering from dengue infection and the presence of a risk factor. The test revealed high count of malaria parasite. Confirmatory PCR identified the parasite to be Plasmodium knowlesi Intravenous artesunate was administered to the patient immediately after acquiring the BFMP result. Severe malaria was complicated with acute kidney injury and septicaemic shock. Fortunately the patient made full recovery and was discharged from the ward after 2 weeks of hospitalisation.
    Matched MeSH terms: Shock, Septic/parasitology
  18. Differential expression of heat shock and floral regulatory genes in pseudocarpel initials of mantled female inflorescences from Elaeis guineensis Jacq
    Ooi SE, Sarpan N, Abdul Aziz N, Nuraziyan A, Ong-Abdullah M
    Plant Reprod, 2019 06;32(2):167-179.
    PMID: 30467592 DOI: 10.1007/s00497-018-0350-5
    KEY MESSAGE: Transcriptomes generated by laser capture microdissected abnormal staminodes revealed adoption of carpel programming during organ initiation with decreased expression of numerousHSPs,EgDEF1, EgGLO1but increasedLEAFYexpression. The abnormal mantled phenotype in oil palm involves a feminization of the male staminodes into pseudocarpels in pistillate inflorescences. Previous studies on oil palm flowering utilized entire inflorescences or spikelets, which comprised not only the male and female floral organs, but the surrounding tissues as well. Laser capture microdissection coupled with RNA sequencing was conducted to investigate the specific transcriptomes of male and female floral organs from normal and mantled female inflorescences. A higher number of differentially expressed genes (DEGs) were identified in abnormal versus normal male organs compared with abnormal versus normal female organs. In addition, the abnormal male organ transcriptome closely mimics the transcriptome of abnormal female organ. While the transcriptome of abnormal female organ was relatively similar to the normal female organ, a substantial amount of female DEGs encode HEAT SHOCK PROTEIN genes (HSPs). A similar high amount (20%) of male DEGs encode HSPs as well. As these genes exhibited decreased expression in abnormal floral organs, mantled floral organ development may be associated with lower stress indicators. Stamen identity genes EgDEF1 and EgGLO1 were the main floral regulatory genes with decreased expression in abnormal male organs or pseudocarpel initials. Expression of several floral transcription factors was elevated in pseudocarpel initials, notably LEAFY, FIL and DL orthologs, substantiating the carpel specification programming of abnormal staminodes. Specific transcriptomes thus obtained through this approach revealed a host of differentially regulated genes in pseudocarpel initials compared to normal male staminodes.
    Matched MeSH terms: Heat-Shock Proteins/genetics*
  19. Differences in dry-bulb temperature do not influence moderate-duration exercise performance in warm environments when vapor pressure is equivalent
    Lei TH, Schlader ZJ, Che Muhamed AM, Zheng H, Stannard SR, Kondo N, et al.
    Eur J Appl Physiol, 2020 Apr;120(4):841-852.
    PMID: 32072226 DOI: 10.1007/s00421-020-04322-8
    PURPOSE: Recent studies have determined that ambient humidity plays a more important role in aerobic performance than dry-bulb temperature does in warm environments; however, no studies have kept humidity constant and independently manipulated temperature. Therefore, the purpose of this study was to determine the contribution of dry-bulb temperature, when vapor pressure was matched, on the thermoregulatory, perceptual and performance responses to a 30-min cycling work trial.

    METHODS: Fourteen trained male cyclists (age: 32 ± 12 year; height: 178 ± 6 cm; mass: 76 ± 9 kg; [Formula: see text]: 59 ± 9 mL kg-1 min-1; body surface area: 1.93 ± 0.12 m2; peak power output: 393 ± 53 W) volunteered, and underwent 1 exercise bout in moderate heat (MOD: 34.9 ± 0.2 °C, 50.1 ± 1.1% relative humidity) and 1 in mild heat (MILD: 29.2 ± 0.2 °C, 69.4 ± 0.9% relative humidity) matched for vapor pressure (2.8 ± 0.1 kPa), with trials counterbalanced.

    RESULTS: Despite a higher weighted mean skin temperature during MOD (36.3 ± 0.5 vs. 34.5 ± 0.6 °C, p 

    Matched MeSH terms: Heat-Shock Response/physiology*
  20. In vitro and in vivo thermal stress induces proliferation of Blastocystis sp
    Thergarajan G, Govind SK, Bhassu S
    Parasitol Res, 2018 Jan;117(1):177-187.
    PMID: 29188368 DOI: 10.1007/s00436-017-5688-3
    Blastocystis sp. is known to be the most commonly found intestinal protozoan parasite in human fecal surveys and has been incriminated to cause diarrhea and abdominal bloating. Binary fission has been widely accepted as the plausible mode of reproduction for this parasite. The present study demonstrates that subjecting the parasites in vitro to higher temperature shows the proliferation of parasite numbers in cultures. Transmission electron microscopy was used to compare the morphology of Blastocystis sp. subtype 3 isolated from a dengue patient having high fever (in vivo thermal stress) and Blastocystis sp. 3 maintained at 41 °C (in vitro thermal stress) and 37 °C (control). Fluorescence stains like acridine orange (AO) and 4',6'-diamino-2-phenylindole (DAPI) were used to demonstrate the viability and nuclear content of the parasite for both the in vitro and in vivo thermal stress groups of parasites. Blastocystis sp. at 37 °C was found to be mostly vacuolar whereas the in vitro thermal stressed isolates at 41 °C were granular with electron dense material seen to protect the granules within the central body. Parasites of the in vivo thermal stressed group showed similar ultrastructure as the in vitro ones. AO and DAPI staining provided evidence that these granules are viable which develop into progenies of Blastocystis sp. These granular forms were then observed to rupture and release progenies from the mother cells whilst the peripheral cytoplasmic walls were seen to degrade. Upon exposure to high temperature both in vitro and in vivo, Blastocystis sp. in cultures show higher number of granular forms seen to be protected by the electron dense material within the central body possibly acting as a protective mechanism. This is possibly to ensure the ability to survive for the granules to be developed as viable progenies for release into the host system.
    Matched MeSH terms: Heat-Shock Response*
Related Terms
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links