A retrospective review of antiphospholipid syndrome: a single tertiary centre experience.

INTRODUCTION: Antiphospholipid syndrome (APS) is a systemic autoimmune disease characterised by thrombosis and pregnancy morbidity in the presence of antiphospholipid antibodies (aPL). Our study aims to study the clinical and laboratory characteristics, treatment strategies and outcomes of APS patients retrospectively. MATERIALS AND METHODS: A retrospective review of all APS patients treated in Rheumatology Unit, Hospital Pulau Pinang between October 2021 and October 2022 was conducted. RESULTS: A total of 53 APS patients (age 42.4±13.9 years) including 22 (41.5%) primary and 31 (58.5%) secondary APS patients were identified. Thrombosis was the most common clinical manifestation (51/53; 96.2%) followed by pregnancy morbidity (15/45; 33.3%). For other clinical manifestations, aPL-associated thrombocytopenia was the most frequently observed manifestation (26.4%) followed by autoimmune haemolytic anaemia (18.9%). Lupus anticoagulant (LA) (88.7%) was the most commonly found aPL followed by anticardiolipin antibody (aCL) (50.9%) and anti-beta 2 glycoprotein 1 antibody (B2GP1) (30.2%). 10 (18.9%) patients tested positive for all three aPL. The majority of our patients (86.8%) receive warfarin as anticoagulation therapy while the remaining receive aspirin or direct oral anticoagulants. CONCLUSION: Our population cohort demonstrated a high incidence of pregnancy morbidities and a similar incidence of thrombotic events compared to other population cohorts in both Asian and the European countries.

A retrospective record review of tuberculous infections in rheumatoid arthritis patients on biologics in Malaysia.

INTRODUCTION: The aim of this study was to analyse the clinical characteristics of patients with rheumatoid arthritis receiving biologics therapy and investigate the association between types of biologics and tuberculosis (TB) infections in 13 tertiary hospitals in Malaysia. MATERIALS AND METHODS: This was a retrospective study that included all RA patients receiving biologics therapy in 13 tertiary hospitals in Malaysia from January 2008 to December 2018. RESULTS: We had 735 RA patients who received biologics therapy. Twenty-one of the 735 patients were diagnosed with TB infection after treatment with biologics. The calculated prevalence of TB infection in RA patients treated with biologics was 2.9% (29 per 1000 patients). Four groups of biologics were used in our patient cohort: monoclonal TNF inhibitors, etanercept, tocilizumab, and rituximab, with monoclonal TNF inhibitors being the most commonly used biologic. The median duration of biologics therapy before the diagnosis of TB was 8 months. 75% of patients had at least one co-morbidity and all patients had at least one ongoing cDMARD therapy at the time of TB diagnosis. More than half of the patients were on steroid therapy with an average prednisolone dose of 5 mg daily. CONCLUSION: Although the study population and data were limited, this study illustrates the spectrum of TB infections in RA patients receiving biologics and potential risk factors associated with biologics therapy in Malaysia.

Correlation of whole blood hydroxychloroquine concentration with cutaneous lupus erythematosus and factors associated with it: First multicenter, cross-sectional analysis in Malaysia.

Hydroxychloroquine (HCQ) is the first-line systemic treatment for cutaneous lupus erythematosus (CLE). Whole blood HCQ concentration (WBHCQ) was found to correlate with CLE severity among Caucasians. However, studies on Asians are scarce. We aim to explore the relationship of WBHCQ with CLE disease activity among multi-racial Malaysians and the factors associated with WBHCQ. A cross-sectional study targeting patients with CLE was conducted from 1 June till 30 November 2019. Disease activity was assessed using Cutaneous Lupus Erythematosus Disease Area and Severity Index - Activity Score (CLASI-AS). Blood was analyzed for WBHCQ concentration using a high-performance liquid chromatography technique. Statistical analysis was done using R studio version 1.2.1335. A total of 88 subjects (male : female, 4.5:1) with a median age of 41 years old were recruited. The median duration CLE was 5 years. The majority had acute cutaneous lupus (n = 45, 51.1%). The median WBHCQ was 946.8 ng/mL. Indians were found to have the highest WBHCQ (median ± interquartile range [IQR], 1515.4 ± 1494.8 ng/mL). Males had a lower WBHCQ (median ± IQR, 733.5 ± 573.8 ng/mL) than females (995.5 ± 925.1 ng/mL). However, no statistically significant association between race and sex with WBHCQ was demonstrable (p = 0.247, p = 0.066). No correlation was demonstrated between WBHCQ and CLASI-AS (r = -0.02, p = 0.851). A positive correlation was found between HCQ dosage (ideal bodyweight) and WBHCQ (r = 0.24, p = 0.027). No other factors were found associated with WBHCQ. Indians and females were observed to have higher WBCHQ; however, no significant correlation was identified. Further study is required to confirm the finding.

Entamoeba infections and associated risk factors among migrant workers in Peninsular Malaysia.

The influx of low skilled migrant workers to Malaysia from low socio-economic countries where gastrointestinal parasitic infections are prevalent has raised concerns about transmission to the local population. Three methods for detection (serology, microscopy and molecular techniques) were utilized to identify Entamoeba infections amongst the targeted cohort and determine risk factors associated with infection. Serological screening of 484 migrant workers from five working sectors in Peninsular Malaysia using IgG4 ELISA based on the rPPDK antigen showed an overall seroprevalence of 7.4% (n = 36; CL95 = 5.3-10.1%) with only one factor statistically associated with seropositivity of anti-amoebic antibodies, i.e. years of residence in Malaysia (χ2 1 = 4.007, p = 0.045). Microscopic examination of 388 faecal samples for protozoan cysts and trophozoites showed a slightly higher prevalence (11.6%; n=45; CL95: 8.4-14.8%). Meanwhile, amplification of the 16S rDNA gene detected two species i.e. Entamoeba dispar (23/388; 5.9%; CL95: 3.6-8.3%) and E. histolytica (11/388; 2.8%; CL95: 1.2-4.5%) and mixed infections with both parasites in only three samples (3/388; 0.8%; CL95: 0.2-2.2%). Entamoeba dispar infection was significantly associated with those employed in food and domestic services (χ2 4 = 12.879, p = 0.012). However, none of the factors affected the prevalence of E. histolytica infection. Despite the low prevalence of E. histolytica in faecal samples of the study cohort, the presence of this pathogenic parasite still poses potential public health risks and calls for tighter control strategies based on better availability of chemotherapeutic treatment and accessibility to appropriate health education.

Entamoeba infections and associated risk factors among migrant workers in Peninsular Malaysia

@#The influx of low skilled migrant workers to Malaysia from low socio-economic countries where gastrointestinal parasitic infections are prevalent has raised concerns about transmission to the local population. Three methods for detection (serology, microscopy and molecular techniques) were utilized to identify Entamoeba infections amongst the targeted cohort and determine risk factors associated with infection. Serological screening of 484 migrant workers from five working sectors in Peninsular Malaysia using IgG4 ELISA based on the rPPDK antigen showed an overall seroprevalence of 7.4% (n = 36; CL95 = 5.3–10.1%) with only one factor statistically associated with seropositivity of anti-amoebic antibodies, i.e. years of residence in Malaysia (χ2 1 = 4.007, p = 0.045). Microscopic examination of 388 faecal samples for protozoan cysts and trophozoites showed a slightly higher prevalence (11.6%; n=45; CL95: 8.4–14.8%). Meanwhile, amplification of the 16S rDNA gene detected two species i.e. Entamoeba dispar (23/388; 5.9%; CL95: 3.6–8.3%) and E. histolytica (11/388; 2.8%; CL95: 1.2–4.5%) and mixed infections with both parasites in only three samples (3/388; 0.8%; CL95: 0.2–2.2%). Entamoeba dispar infection was significantly associated with those employed in food and domestic services (χ2 4 = 12.879, p = 0.012). However, none of the factors affected the prevalence of E. histolytica infection. Despite the low prevalence of E. histolytica in faecal samples of the study cohort, the presence of this pathogenic parasite still poses potential public health risks and calls for tighter control strategies based on better availability of chemotherapeutic treatment and accessibility to appropriate health education.

Molecular epidemiology of Cryptosporidium in HIV/AIDS patients in Malaysia.

Cryptosporidiosis is a particular concern in immunocompromised individuals where symptoms may be severe. The aim of this study was to examine the epidemiological and molecular characteristics of Cryptosporidium infections in HIV/AIDS patients in Malaysia in order to identify risk factors and facilitate control measures. A modified Ziehl-Neelsen acid fast staining method was used to test for the presence of Cryptosporidium oocysts in the stools of 346 HIV/AIDS patients in Malaysia. Standard coproscopical methods were used to identify infections with other protozoan or helminths parasites. To identify the species of Cryptosporidium, DNA was extracted and nested-PCR was used to amplify a portion of the SSU rRNA gene. A total of 43 (12.4%) HIV-infected patients were found to be infected with Cryptosporidium spp. Of the 43 Cryptosporidium-positive HIV patients, 10 (23.3%) also harboured other protozoa, and 15 (34.9%) had both protozoa and helminths. The highest rates of cryptosporidiosis were found in adult males of Malay background, intravenous drug users, and those with low CD4 T cell counts (i.e., < 200 cells/mm3). Most were asymptomatic and had concurrent opportunistic infections mainly with Mycobacterium tuberculosis. DNA sequence analysis of 32 Cryptosporidium isolates identified C. parvum (84.3%), C. hominis (6.3%), C. meleagridis (6.3%), and C. felis (3.1%). The results of the present study revealed a high prevalence of Cryptosporidium infection in hospitalized HIV/AIDS patients. The results also confirmed the potential significance of zoonotic transmission of C. parvum in HIV infected patients, as it was the predominant species found in this study. However, these patients were found to be susceptible to a wide range of Cryptosporidium species. Epidemiological and molecular characterization of Cryptosporidium isolates provides clinicians and researchers with further information regarding the origin of the infection, and may enhance treatment and control strategies.

A rare case of nasopharyngeal carcinosarcoma.

Nasopharnygeal carcinoma is known to be the commonest tumour of the nasopharynx. However, the incidence of nasopharngeal carcinosarcoma is extremely rare. Carcinosarcoma has been reported to be aggressive in nature and therefore early diagnosis and prompt treatment is important. We report a young lady who was diagnosed with nasopharyngeal carcinosarcoma in our centre. She presented with only 2 weeks history of nose block and was noted to have a mass occupying the nasopharynx with neck metastasis. She underwent panendoscope and biopsy with radical radiotherapy.

A young patient with history of Kawasaki disease presenting with triple vessel disease.

Kawasaki disease is primarily a condition that affects young children and it is associated with cardiac morbidity and mortality. This disease has been known to cause coronary artery aneurysms which occurs as a sequelae of vasculitis. The progression of triple vessel disease in adult which results from cardiac complications from Kawasaki disease is rare. We report a case of a young man with history of Kawasaki disease at infancy presenting with triple vessel disease requiring cardiac bypass surgery at the age of 20 years old.

Genomic imprinting effects in a compromised in utero environment: implications for a healthy pregnancy.

Genomic imprinting in gametogenesis marks a subset of mammalian genes for parent-of-origin-dependent monoallelic expression in the offspring. In mice, the identification and manipulation of individual imprinted genes has shown that the diverse products of these genes are largely devoted to controlling pre- and postnatal growth. Human syndromes with parental origin effects have been characterized both at the phenotypic and genotypic levels, allowing further elucidation of the function and regulation of imprinted genes. Evidence suggests that a compromised in utero environment influences fetal growth through the modulation of epigenetic states. However it is not known whether imprinted genes, by their nature, might be more or less susceptible to such environmental influences. Here we review the progress made in addressing the influence of a compromised in utero environment on the behavior of imprinted genes. We also examine whether these environmental influences may have an impact on the later development of human disease.

Hypoxia signals autophagy in tumor cells via AMPK activity, independent of HIF-1, BNIP3, and BNIP3L.

Macroautophagy (called autophagy hereafter) is a catabolic process activated by various types of stress, most notably by nutrient deprivation. The autophagic degradation of intracellular macromolecules provides metabolic support for the cell; however, this physiological process can also initiate a form of cell death (type 2 programmed cell death). Here we report that oxygen deprivation can activate the autophagic pathway in human cancer cell lines. We observed that hypoxia induced distinct cellular changes characteristic of autophagy such as an increase in cytoplasmic acidic vesicles, and processing and cellular localization of microtubule-associated protein-1 light chain 3. Oxygen deprivation-induced autophagy did not require nutrient deprivation, hypoxia-inducible factor-1 (HIF-1) activity, or expression of the HIF-1 target gene BNIP3 (Bcl-2 adenovirus E1a nineteen kilodalton interacting protein 3) or BNIP3L (BNIP3 like protein). Hypoxia-induced autophagy involved the activity of 5'-AMP-activated protein kinase (AMPK). Finally, we determined that cells lacking the autophagy gene ATG5 were unable to activate the autophagic machinery in hypoxia, had decreased oxygen consumption and increased glucose uptake under hypoxia, had increased survival in hypoxic environments, and exhibited accelerated growth as xenografted tumors. Together, these findings suggest that the autophagic degradation of cellular macromolecules contributes to the energetic balance governed by AMPK, and that suppression of autophagy in transformed cells can increase both resistance to hypoxic stress and tumorigenicity.

Ambulatory surgery and anaesthesia in HUKM, a teaching hospital in Malaysia: the first two years experience.

Ambulatory or day care surgery is still in its infancy in this part of the world. Our newly built university affiliated hospital started its Day Surgery Centre in February 1998. It is the first multidisciplinary ambulatory surgery centre in a teaching hospital in the country. It caters for Orthopaedic surgery, Urology, Plastic surgery, Otorhinolaryngology, General surgery, Paediatric surgery and Ophthalmology. We have done 2,604 cases and our unanticipated admission rate is less than 2%. There has been no major morbidity or mortality. The problems of setting up a multidisciplinary ambulatory centre in a teaching hospital are discussed.

Cardiac myocytes express mRNA for ten RGS proteins: changes in RGS mRNA expression in ventricular myocytes and cultured atria.

Regulators of G-protein signalling (RGS) are recently identified proteins that shorten the lifetime of the activated G protein. We now show that rat cardiac myocytes express mRNA for at least 10 RGS. The mRNA for RGS-r is barely detectable in rat ventricles, but increases more than 20-fold during the 60- to 90-min process of isolating ventricular myocytes, and after 90 min of culture of atrial pieces in medium with Ca2+. Both in myocytes and in atria, the rise in RGS-r is transient. The mRNA for cardiac RGS5, but not RGS-r, is developmentally regulated. These studies suggest that rapid regulation of RGS levels may be a new mechanism that governs how signals are transmitted across the cardiac cell membrane.

Role of the pro-alpha2(I) COOH-terminal region in assembly of type I collagen: truncation of the last 10 amino acid residues of pro-alpha2(I) chain prevents assembly of type I collagen heterotrimer.

Procollagen (Type I) contains a noncollagenous COOH-terminal propeptide (C-propeptide) hypothesized to be important in directing chain association and alignment during assembly. We previously expressed human pro-alpha2(I) cDNA in rat liver epithelial cells, W8, that produce only pro-alpha1(I) trimer collagen (Lim et al. [1994] Matrix Biol. 14: 21-30). In the resulting cell lines, alpha2(I) assembled with alpha1(I) forming heterotrimers. Using this cell system, we investigated the importance of the COOH-terminal propeptide sequence of the pro-alpha2(I) chain for normal assembly of type I collagen. Full-length human pro-alpha2(I) cDNA was cloned into expression vectors with a premature stop signal eliminating the final 10 amino acids. No triple-helical molecules containing alpha2(I) were detected in transfected W8 cells, although pro-alpha2(I) mRNA was detected. Additional protein analysis demonstrated that these cells synthesize small amounts of truncated pro-alpha2(I) chains detected by immunoprecipitation with a pro-alpha2(I) antibody. In addition, since the human-rat collagen was less thermostable than normal intraspecies collagen, wild-type and C-terminal truncated mouse cDNAs were expressed in mouse D2 cells, which produced only type I trimers. Results from both systems were consistent, suggesting that the last 10 amino acid residues of the pro-alpha2(I) chain are important for formation of stable type I collagen.

A study of pollen prevalence in relation to pollen allergy in Malaysian asthmatics.

In this paper we report results of skin prick tests (SPT) using pollen extracts on 200 patients with clinical symptoms of asthma, and results of a parallel study in which pollen was collected and classified over a period of 18 months. The patients were outpatients from the University Hospital in Kuala Lumpur, Malaysia, while the pollen grains were collected with a spore trap placed in the campus of the University of Malaya, approximately one kilometer from the University Hospital. Pollen extracts of 3 grasses (Bahia, Bermuda, rough pigweed) and 2 flowering trees, Acacia and Melaleuca, were used in the SPT. Of the 29.5% asthmatics with positive SPT reactions, 21.5% were to one or more of the grass pollens, 21.5% to Acacia and 7.5% to Melaleuca pollen. Acacia and Bermuda grass extracts were the most allergenic, which agreed with results of the pollen collection which showed grass and Acacia pollen grains to be the two most commonly found pollens.

Identification of critical amino acid residues of Saccharomyces cerevisiae carbamoyl-phosphate synthetase: definition of the ATP site involved in carboxy-phosphate formation.

Carbamoyl-phosphate synthetases (CPSases) utilize two molecules of ATP at two homologous domains, B and C, with ATP(B) used to form the enzyme-bound intermediate carboxy-phosphate and ATP(C) used to phosphorylate the carbamate intermediate. To further define the role of one CPSase peptide suggested by affinity labeling studies to be near the ATP(B) site, we have carried out site-directed mutagenic analysis of peptide 234-242 of the Saccharomyces cerevisiae arginine-specific CPSase. Mutants E234A, E234D, E236A, E236D and E238A were unable to complement the CPSase-deficient yeast strain LPL26 whereas mutants Y237A, E238D, R241K, R241E and R241P supported LPL26 growth as well as wild-type CPSase. Kinetic analysis of E234A and Y237A indicated impaired utilization of ATP(B) but not of ATP(C). D242A, a temperature-sensitive mutant, retained no detectable activity when assayed in vitro. These findings, together with the affinity labeling data and primary sequence analysis, strongly suggest that the yeast CPSase peptide 234-242 is located at the ATP(B) site and that some of its residues are important for functioning of the enzyme. D242 appears to occupy a critical structural position and E234, E236 and E238 appear to be critical for function, with the spatial arrangement of the carboxyl side chain also critical for E234 and E236.

Critical roles for arginine 1061/1060 and tyrosine 1057 in Saccharomyces cerevisiae arginine-specific carbamoyl-phosphate synthetase.

Carbamoyl-phosphate synthetases (CPSases) bind two molecules of ATP at two internally duplicated domains. Previous affinity labeling studies with the ATP analog 5'-p-fluorosulfonylbenzoyladenosine (FSBA; Kim, H., Kelly, R. E., and Evans, D. R. (1991) Biochemistry 30, 10322-10329; Potter, M. D., and Powers-Lee, S. G. (1992) J. Biol. Chem. 267, 2023-2031) have identified several peptides as being near the ATP sites, with most of the FSBA-labeled peptides localized to the internally duplicated domains. However, two of the FSBA-labeled peptides were localized to the third domain of CPSase, an autonomously folded but flexible domain at the extreme C-terminus of the protein. These findings suggested that the C-terminal domain is also involved in interaction with both molecules of ATP and that it might serve to complement the ATP binding sites on the duplicated domains by participating in catalytic processing of the ATP molecules. To further define the role of the C-terminal domain in ATP utilization, we have now carried out site-directed mutagenic analysis of peptide 1052-1061 of the Saccharomyces cerevisiae arginine-specific CPSase. Aspartate residues at positions 1053, 1054, and 1056 did not appear to play a significant role in CPSase structure or function. However, tyrosine 1057 was critical for CPSase structure and the presence of one of the tandem arginyl residues at positions 1061 and 1060 was critical for CPSase catalytic function.

Requirement for the carboxyl-terminal domain of Saccharomyces cerevisiae carbamoyl-phosphate synthetase.

The arginine-specific carbamoyl phosphate synthetase of Saccharomyces cerevisiae is a heterodimeric enzyme, with a 45-kDa CPA1 subunit binding and cleaving glutamine, and a 124-kDa CPA2 subunit accepting the ammonia moiety cleaved from glutamine, binding all of the remaining substrates and carrying out all of the other catalytic events. CPA2 is composed of two apparently duplicated amino acid sequences involved in binding the two ATP molecules needed for carbamoyl phosphate synthesis and a carboxyl-terminal domain which appears to be less tightly folded than the remainder of the protein. Using deletion mutagenesis, we have established that essentially all of the carboxyl-terminal domain of CPA2 is required for catalytic function and that even small truncations lead to significant changes in the CPA2 conformation. In addition, we have demonstrated that the C-terminal region of CPA2 can be expressed as an autonomously folded unit which is stabilized by specific interactions with the remainder of CPA2. We also made the unexpected finding that, even when ammonia is used as the substrate and there is no catalytic role for CPA1, interaction with CPA1 led to an increase in the Vmax of CPA2 in crude extracts.

Can the mudskipper, Periophthalmus chrysospilos, tolerate acute environmental hypoxic exposure?

The mudskipper P. chrysospilos became inert at 0.76 µl O2.ml(-1) when it was allowed to respire in a 'closed respiratory chamber'. No ethanol was detected although it excreted three times more total carbon dioxide into the surrounding sea water than the amount of oxygen consumed. However, P. chrysospilos could survive environmental hypoxic exposure (0.8 µl O2.ml(-1)) for at least 6 h. Upon normoxic recovery, the oxygen debt repayment was only a small fraction of the oxygen deficit incurred during the 6 h of hypoxic exposure. It would therefore appear that P. chrysospilos was able to cope with environmental hypoxia by suppressing its metabolic rate.

Susceptibility to antimicrobials of Neisseria gonorrhoeae isolated in Singapore: implications on the need for more effective treatment regimens and control strategies.

The antimicrobial susceptibility of gonococci isolated in Singapore has been studied over several years. In 1983, the prevalence of penicillinase producing Neisseria gonorrhoeae (PPNG) was 33.5% and 64% of non-PPNG isolates had minimum inhibitory concentrations (MICs) of penicillin of greater than or equal to 0.5 mg/l. After a control programme, the isolation of the gonococcus from prostitutes was reduced and there was improvement in its susceptibility to antimicrobials. The incidence of PPNG strains was stabilised with a change in the treatment regimen. An influx of foreign prostitutes, however, had an unfavourable impact on these variables. Countries in South East Asia have a high prevalence of PPNG and non-PPNG strains that have reduced susceptibility to antimicrobials. In view of increased air travel the problem should be seen from a global perspective. Better treatment regimens and control strategies are urgently needed.