Extracellular BSA-degrading SAPs in the rare pathogen Meyerozyma guilliermondii strain SO as potential virulence factors in candidiasis.

Meyerozyma guilliermondii (Candida guilliermondii) is one of the Candida species associated with invasive candidiasis. With the potential for expressing industrially important enzymes, M. guilliermondii strain SO possessed 99 % proteome similarity with the clinical ATCC 6260 isolate and showed pathogenicity towards zebrafish embryos. Recently, three secreted aspartyl proteinases (SAPs) were computationally identified as potential virulence factors in this strain without in vitro verification of SAP activity. The quantification of Candida SAPs activity in liquid broth were also scarcely reported. Thus, this study aimed to characterize M. guilliermondii strain SO's ability to produce SAPs (MgSAPs) in different conditions (morphology and medium) besides analyzing its growth profile. MgSAPs' capability to cleave bovine serum albumin (BSA) was also determined to propose that MgSAPs as the potential virulence factors compared to the avirulent Saccharomyces cerevisiae. M. guilliermondii strain SO produced more SAPs (higher activity) in yeast nitrogen base-BSA-dextrose broth compared to yeast extract-BSA-dextrose broth despite insignificantly different SAP activity in both planktonic and biofilm cells. FeCl3 supplementation significantly increased the specific protein activity (∼40 %). The BSA cleavage by MgSAPs at an acidic pH was proven through semi-quantitative SDS-PAGE, sharing similar profile with HIV-1 retropepsin. The presented work highlighted the MgSAPs on fungal cell wall and extracellular milieu during host infection could be corroborated to the quantitative production in different growth modes presented herein besides shedding lights on the potential usage of retropepsin's inhibitors in treating candidiasis. Molecular and expression analyses of MgSAPs and their deletion should be further explored to attribute their respective virulence effects.

Clinical and Laboratory Diagnosis of Antiphospholipid Syndrome: A Review.

The antiphospholipid syndrome (APS) manifests through venous or arterial thrombosis, with or without pregnancy complication alongside the continuous presence of antiphospholipid antibodies (aPL). APS classification relies on three aPL subtypes: anticardiolipin (aCL), anti-ß2-glycoprotein I antibodies (anti-ß2GPI), and lupus anticoagulants (LA) antibodies. Given that thrombosis and pregnancy issues are not unique to APS, the precise and reliable identification of aPL forms the basis for diagnosis. Semi-quantitative solid-phase assays identify two antibodies, aCL and anti-ß2GPI, while LA detection occurs through various phospholipid-dependent coagulation assays that are based on antibody behaviour. LA, specifically, is conclusively associated with thrombosis, prompting discussions around the serological criteria for APS. Despite advancements in LA detection, the standardisation of all aPL detection assays remains imperative. The combined presence of aCL and anti-ß2GPI with thrombosis inconsistently triggers concern. Initial presentations by APS patients commonly exhibit a heightened risk of stroke, miscarriages in the later stages of pregnancy, positive results of LA tests, and widespread thrombosis across multiple organs, often leading to adverse outcomes. Correctly diagnosing this condition is pivotal to avoid unnecessary long-term secondary thromboprophylaxis.

Red Blood Cell Alloimmunization in Pregnancy: A Review of the Pathophysiology, Prevalence, and Risk Factors.

This review paper provides an overview of the risk factors and laboratory testing for red blood cell (RBC) alloimmunization in pregnancy. RBC alloimmunization is a significant medical issue that can cause haemolytic disease of the fetus and newborn (HDFN), leading to neonatal morbidity and mortality. Current HDFN prophylaxis targets only Rhesus D (RhD) alloimmunization, with no effective measures to prevent alloimmunization to other RBC antigen groups. Several factors can increase the risk of developing RBC alloimmunization during pregnancy, including fetomaternal haemorrhage, RBC and maternal genetic status, and previous transfusions. Identifying these risk factors is essential to execute the appropriate management strategies to minimize the risk of HDFN. The review also discusses the laboratory methods and overview of pregnancy management. The paper highlights the importance of identifying and managing the risk factors for RBC alloimmunization in pregnancy to minimize the risk of HDFN and improve neonatal outcomes.

Identification and characterization of a promiscuous metallohydrolase in metallo-ß-lactamase superfamily from a locally isolated organophosphate-degrading Bacillus sp. strain S3wahi.

In this present study, characteristics and structure-function relationship of an organophosphate-degrading enzyme from Bacillus sp. S3wahi were described. S3wahi metallohydrolase, designated as S3wahi-MH (probable metallohydrolase YqjP), featured the conserved αß/ßα metallo-ß-lactamase-fold (MBL-fold) domain and a zinc bimetal at its catalytic site. The metal binding site of S3wahi-MH also preserves the H-X-H-X-D-H motif, consisting of specific amino acids at Zn1 (Asp69, His70, Asp182, and His230) and Zn2 (His65, His67, and His137). The multifunctionality of S3wahi-MH was demonstrated through a steady-state kinetic study, revealing its highest binding affinity (KM) and catalytic efficiency (kcat/KM) for OP compound, paraoxon, with values of 8.09 × 10-6 M and 4.94 × 105 M-1 s-1, respectively. Using OP compound, paraoxon, as S3wahi-MH native substrate, S3wahi-MH exhibited remarkable stability over a broad temperature range, 20 °C - 60 °C and a broad pH tolerance, pH 6-10. Corresponded to S3wahi-MH thermal stability characterization, the estimated melting temperature (Tm) was found to be 72.12 °C. S3wahi-MH was also characterized with optimum catalytic activity at 30 °C and pH 8. Additionally, the activity of purified S3wahi-MH was greatly enhanced in the presence of 1 mM and 5 mM of manganese (Mn2+), showing relative activities of 1323.68 % and 2073.68 %, respectively. The activity of S3wahi-MH was also enhanced in the presence of DMSO and DMF, showing relative activities of 270.37 % and 307.41 %, respectively. The purified S3wahi-MH retained >60 % residual activity after exposure to non-ionic Tween series surfactants. Nevertheless, the catalytic activity of S3wahi-MH was severely impacted by the treatment of SDS, even at low concentrations. Considering its enzymatic properties and promiscuity, S3wahi-MH emerges as a promising candidate as a bioremediation tool in wide industrial applications, including agriculture industry.

Hematological Profile of Hb Adana Among High School Students in Northeast Peninsular Malaysia.

Background Hb Adana is a non-deletional alpha (α)-thalassaemia variant resulting from mutations in α1- or α2-globin codon 59 (αCD59), leading to the production of unstable α-globin. Clinical manifestations can vary from silent carrier status to dependence on blood transfusions, hepatosplenomegaly, skeletal deformities, and spinal cord compression. Despite the significance of Hb Adana inheritance, studying this variant poses challenges due to the scarcity of molecular tests and the potential for routine diagnoses to be overlooked. This study aims to investigate the prevalence of Hb Adana among local high school students and assess the hematological parameters and hemoglobin analysis of Hb Adana in Malaysia. Methodology This retrospective study analyzed 13,721 blood samples collected from high school students participating in Malaysia's National Thalassaemia Screening Program at Hospital Raja Perempuan Zainab II (HRPZ II). Deletional α-thalassaemia was detected using multiplex gap-polymerase chain reaction (PCR), while common non-deletional α-thalassaemia was identified using multiplex amplification refractory mutation system (ARMS) PCR. Data were extracted from the HRPZ II database for analysis. Results Among the participants, 2327 individuals were found to have either common deletional (n=1037, 44.6%) or non-deletional (n=1290, 55.4%) α-thalassaemia. Hb Constant Spring was the most prevalent non-deletional α-thalassaemia, accounting for 53.03% of cases. Thirty-one participants (1.33%) exhibited αCD59α/αα, and one (0.04%) had αCD59α/-α3.7. Among the 32 subjects with Hb Adana, 87.5% were Malay, and 12.5% were Orang Asli. Additionally, seven cases of HbE/Hb Adana co-inheritance were identified. Hemoglobin levels in heterozygous Hb Adana individuals ranged from mild anemia to normal, between 95 g/L and 153 g/L. Mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH) were approximately 73 fL and 23 pg, respectively. Conclusion This study delineates the distribution of α-thalassaemia mutation patterns among high school students in Kelantan, Northeast Peninsular Malaysia. Our findings indicate that Hb Adana is rare in our region and co-inheritance with an α-gene deletion results in α+-thalassaemia and with HbE, α0-thalassaemia. All heterozygous Hb Adana individuals exhibited low MCVs and MCHs.

Mannose-binding lectin gene sequence data in Kelantan population.

The human mannose-binding lectin (MBL) gene encodes a polymorphic protein that plays a crucial role in the innate immune response. Human MBL deficiency is associated with immunodeficiencies, and its variants have been linked to autoimmune and infectious diseases. Despite this significance, gene studies concerning MBL sequencing are uncommon in Malaysia. Therefore, we aimed to preliminary described the human MBL sequencing dataset based on the Kelantan population. Blood samples were collected from 30 unrelated individuals and underwent DNA extraction, genotyping, and sequencing. The sequencing data generated 886 bp, which were deposited in GenBank (ON619541-ON619546). Allelic variants were identified and translated into six MBL haplotypes: HYPA, HYPB, LYPB, LXPB, HXPA, and LXPA. An evolutionary tree was constructed using the haplotype sequences. These findings contribute to the expansion of MBL information within the country, providing a valuable baseline for future research exploring the association between the gene and targeted diseases.

The Blood Donor Deferral Rate and the Reasons for Deferral at a Tertiary Care Teaching Institute in Northeastern Malaysia.

A deferral takes place when donors fail to meet the eligibility criteria for donating blood during their visit to a blood collection site. Deferral periods, which can be either permanent or temporary, are implemented to protect the well-being of both the donor and the recipient. This study aimed to investigate the frequency of deferrals and the various factors contributing to them. A retrospective analysis was conducted at the Transfusion Medicine Unit of Hospital Universiti Sains Malaysia (USM), utilizing data obtained from blood donors during the period from January 2022 to June 2023. The research included a cohort of 18,751 donors who visited our transfusion unit for blood donation. Data, including gender, age, and reasons for deferral, were collected by reviewing the records of donors who were deferred. Descriptive statistics were employed to analyze the data of deferral blood donors. Out of 18,751 blood donors, 3,533 (18.84%) were deferred, consisting of 1,267 males (35.86%) and 2,266 females (64.14%). The age group of 18-25 years accounted for the highest number, comprising 1,875 donors (53.07%). Among the deferred cases, 53.33% were first-time donors, followed by 25.28% regular donors and 21.40% lapsed donors. The deferral of blood donors resulted from various reasons. The most common cause of overall deferral among blood donors was low hemoglobin (38.33%), followed by upper respiratory tract infections (8.38%), chronic medical illness (7.08%), and high blood pressure (7.02%). Temporary deferrals were more prevalent than permanent deferrals, accounting for 91.57% of cases compared to 8.43% for permanent deferrals. Voluntary non-remunerative blood donors constitute the backbone for a safe and reliable blood supply in transfusion services. Utilizing a comprehensive database will enable effective counseling of temporarily deferred donors, providing insights into the reasons for their deferral, the expected duration, and the appropriate treatments. This information is crucial for motivating these donors to recruit again in the donor pool. Public education initiatives aimed at raising awareness about the causes of deferral and promoting regular health check-ups can play a pivotal role in minimizing these deferrals.

The Evaluation of Ordinal Regression Model's Performance Through the Implementation of Multilayer Feed-Forward Neural Network: A Case Study of Hypertension.

Background Hypertension, or high blood pressure, is a common medical condition that affects a significant portion of the global population. It is a major risk factor for cardiovascular diseases (CVD), stroke, and kidney disorders. Objective The objective of this study is to create and validate a model that combines bootstrapping, ordered logistic regression, and multilayer feed-forward neural networks (MLFFNN) to identify and analyze the factors associated with hypertension patients who also have dyslipidemia. Material and methods A total of 33 participants were enrolled from the Hospital Universiti Sains Malaysia (USM) for this study. In this study, advanced computational statistical modeling techniques were utilized to examine the relationship between hypertension status and several potential predictors. The RStudio (Posit, Boston, MA) software and syntax were implemented to establish the relationship between hypertension status and the predictors. Results The statistical analysis showed that the developed methodology demonstrates good model fitting through the value of predicted mean square error (MSE), mean absolute deviance (MAD), and accuracy. To evaluate model fitting, the data in this study was divided into distinct training and testing datasets. The findings revealed that the results strongly support the superior predictive capability of the hybrid model technique. In this case, five variables are considered: marital status, smoking status, systolic blood pressure, fasting blood sugar levels, and high-density lipoprotein levels. It is important to note that all of them affect the hazard ratio: marital status (ß1, -17.12343343; p < 0.25), smoking status (ß2, 1.86069121; p < 0.25), systolic blood pressure (ß3, 0.05037332; p < 0.25), fasting blood sugar (ß4, -0.53880322; p < 0.25), and high-density lipoprotein (ß5, 5.38065556; p < 0.25). Conclusion This research aims to develop and extensively evaluate the hybrid approach. The statistical methods employed in this study using R language show that regression modeling surpasses R-squared values in predicting the mean square error. The study's conclusion provides strong evidence for the superiority of the hybrid model technique.

Exploring the Antarctic aminopeptidase P from Pseudomonas sp. strain AMS3 through structural analysis and molecular dynamics simulation.

Aminopeptidase P (APPro) is a crucial metalloaminopeptidase involved in amino acid cleavage from peptide N-termini, playing essential roles as versatile biocatalysts with applications ranging from pharmaceuticals to industrial processes. Despite acknowledging its potential for catalysis in lower temperatures, detailed molecular basis and biotechnological implications in cold environments are yet to be explored. Therefore, this research aims to investigate the molecular mechanisms underlying the cold-adapted characteristics of APPro from Pseudomonas sp. strain AMS3 (AMS3-APPro) through a detailed analysis of its structure and dynamics. In this study, structure analysis and molecular dynamics (MD) simulation of a predicted model of AMS3-APPro has been performed at different temperatures to assess structural flexibility and thermostability across a temperature range of 0-60 °C over 100 ns. The MD simulation results revealed that the structure were able to remain stable at low temperatures. Increased temperatures present a potential threat to the overall stability of AMS3-APPro by disrupting the intricate hydrogen bond networks crucial for maintaining structural integrity, thereby increasing the likelihood of protein unfolding. While the metal binding site at the catalytic core exhibits resilience at higher temperatures, highlighting its local structural integrity, the overall enzyme structure undergoes fluctuations and potential denaturation. This extensive structural instability surpasses the localized stability observed at the metal binding site. Consequently, these assessments offer in-depth understanding of the cold-adapted characteristics of AMS3-APPro, highlighting its capability to uphold its native conformation and stability in low-temperature environments. In summary, this research provides valuable insights into the cold-adapted features of AMS3-APPro, suggesting its efficient operation in low thermal conditions, particularly relevant for potential biotechnological applications in cold environments.Communicated by Ramaswamy H. Sarma.

Coagulation Status Using Clot Wave Analysis in Patients With Prolonged Immobilization.

Background Prolonged immobilization is widely recognized as a risk factor for thromboembolism. In this prospective study, we investigated the changes in clot waveform analysis (CWA) parameters in prolonged immobilized patients following lower limb trauma. CWA is an advanced method for assessing global coagulation that involves continuously monitoring changes in light transmittance, absorbance, or light scattering during routine clotting tests. Additionally, we also aim to determine the CWA parameters between day one and after day three of immobilization. Methods A total of 30 patients with prolonged immobilization were enrolled in this study. The plasma of these patients was collected on the first day of their admission and subsequently obtained again after day three of immobilization. Prothrombin time (PT)-based CWA and activated partial thromboplastin time (aPTT)-based CWA were performed using the ACL TOP 300 CTS (Werfen: Bedford, USA) coagulation analyzer, which utilizes the optical method for clot detection. Plasma samples for 20 normal controls were recruited from a healthy blood donor. The CWA parameters generated during clot formation were analyzed. For the comparison of CWA parameters between patients with prolonged immobilization and healthy controls, the Mann-Whitney test was used. A paired t-test was used for the comparison of clot wave parameters between day one and after day three of immobilization. This study was approved by the Universiti Sains Malaysia Research Ethics Committee. Result The mean values of PT and aPTT in healthy controls were 11.66 seconds and 33.98 seconds, respectively. There was no statistically significant difference between the patients and the healthy controls in the median values of aPTT (P=0.935). However, patients with prolonged immobilization exhibited significantly higher median PT CWA parameter values than controls (P=0.007). These parameters included the delta change (P<0.001), peak time velocity (P=0.008), and height velocity (P<0.001). On the other hand, the delta change (P<0.001) and height velocity (P<0.001) of the aPTT CWA parameters were significantly higher in patients with prolonged immobilization than in controls. In patients with prolonged immobilization, there was no significant difference in PT CWA parameters between day one and after day three of immobilization, while for aPTT CWA, all parameters were higher on day three, except for the endpoint time. Conclusion Patients with prolonged immobilization exhibit increased PT and aPTT CWA parameters compared to normal controls. CWA parameters could aid in identifying patients at risk of developing thrombosis through changes in the clot waveform. However, further study is needed to fully utilize additional information from routine coagulation testing.

Haemostatic, Inflammatory, and Haematological Biomarkers Among Orthopaedic Patients With Prolonged Immobilization and the Risk of Hypercoagulable States.

Background Venous thromboembolism (VTE) is a common and potentially life-threatening complication in patients with lower limb traumatic fractures. Orthopaedic patients who experience trauma in the lower limbs with prolonged immobilization may experience a hypercoagulable state, which could eventually lead to the development of VTE. Therefore, this study aims to evaluate the changes in hypercoagulable markers, including haemostatic, inflammatory, and haematological biomarkers in orthopaedic trauma patients with prolonged immobilization. Materials/method This prospective cohort study was conducted at Hospital Universiti Sains Malaysia from August 2020 to March 2022. Every patient with fractures in the lower limbs was screened for eligibility, and patients who required immobilization for more than five days without receiving anticoagulant prophylaxis were recruited for this study. The laboratory tests, including D-dimer, fibrinogen, prothrombin time (PT), activated partial thromboplastin time (aPTT), erythrocyte sedimentation rate (ESR), and platelet count, were serially measured on day one and day five of hospitalization. The biomarkers were analyzed using a paired t-test, with a p-value <0.05 as a significant result. Results A total of 54 patients with fractures in the lower limbs, ages ranging from 12 to 50 years old, were involved in this study. The paired t-test analysis demonstrated that several biomarkers showed a significant increase in mean difference between day one and day five of immobilization, which included fibrinogen, ESR, and platelet count. The mean differences for each biomarker with fibrinogen were 0.66 g/L (p<0.001, 95% CI of mean difference: -1.04, -0.27), ESR increased by 17.98mm/hr (p<0.001, 95% CI of mean difference: -24.69, -11.27), and platelet count increased by 128.59×109/L (p<0.001, 95% CI of mean difference: -166.55, -90.64) on day five of immobilization. D-dimer was elevated in all patients on both post-trauma days; however, no significant difference was observed in this biomarker between day one and day five of immobilization. Conclusion In conclusion, our study found that fibrinogen, ESR, and platelet count levels were significantly increased in orthopaedic trauma patients with prolonged immobilization. The increase in these biomarkers indicates the body's reaction to tissue injury after trauma, which may contribute to the hypercoagulable states. Further research with a larger sample size is warranted to assess the viability of these biomarkers as potential diagnostic indicators for the development of VTE related to hypercoagulability.

Features of the rare pathogen Meyerozyma guilliermondii strain SO and comprehensive in silico analyses of its adherence-contributing virulence factor agglutinin-like sequences.

Meyerozyma guilliermondii is a rare yeast pathogen contributing to the deadly invasive candidiasis. M. guilliermondii strain SO, as a promising protein expression host, showed 99% proteome similarity with the clinically isolated ATCC 6260 (type strain) in a recent comparative genomic analysis. However, their in vitro virulence features and in vivo pathogenicity were uncharacterized. This study aimed to characterize the in vitro and in vivo pathogenicity of M. guilliermondii strain SO and analyze its Als proteins (MgAls) via comprehensive bioinformatics approaches. M. guilliermondii strain SO showed lower and higher sensitivity towards ß-mercaptoethanol and lithium, respectively than the avirulent S. cerevisiae but exhibited the same tolerance towards cell wall-perturbing Congo Red with C. albicans. With 7.5× higher biofilm mass, M. guilliermondii strain SO also demonstrated 75% higher mortality rate in the zebrafish embryos with a thicker biofilm layer on the chorion compared to the avirulent S. cerevisiae. Being one of the most important Candida adhesins, sequence and structural analyses of four statistically identified MgAls showed that MgAls1056 was predicted to exhibit the most conserved amyloid-forming regions, tandem repeat domain and peptide binding cavity (PBC) compared to C. albicans Als3. Favoured from the predicted largest ligand binding site and druggable pockets, it showed the highest affinity towards hepta-threonine. Non-PBC druggable pockets in the most potent virulence contributing MgAls1056 provide new insights into developing antifungal drugs targeting non-albicans Candida spp. Virtual screening of available synthetic or natural bioactive compounds and MgAls1056 deletion from the fungal genome should be further performed and validated experimentally.Communicated by Ramaswamy H. Sarma.

Worldwide trend discovery of structural and functional relationship of metallo-ß-lactamase for structure-based drug design: A bibliometric evaluation and patent analysis.

Metallo-ß-lactamase (MBL) is an enzyme produced by clinically important bacteria that can inactivate many commonly used antibiotics, making them a significant concern in treating bacterial infections and the risk of having high antibiotic resistance issues among the community. This review presents a bibliometric and patent analysis of MBL worldwide research trend based on the Scopus and World Intellectual Property Organization databases in 2013-2022. Based on the keywords related to MBL in the article title, abstract, and keywords, 592 research articles were retrieved for further analysis using various tools such as Microsoft Excel to determine the frequency analysis, VOSviewer for bibliometric networks visualization, and Harzing's Publish or Perish for citation metrics analysis. Standard bibliometric parameters were analysed to evaluate the field's research trend, such as the growth of publications, topographical distribution, top subject area, most relevant journal, top cited documents, most relevant authors, and keyword trend analysis. Within 10 years, MBL discovery has shown a steady and continuous growth of interest among the community of researchers. United States of America, China, and the United Kingdom are the top 3 countries contribute high productivity to the field. The patent analysis also shows several impactful filed patents, indicating the significance of development research on the structural and functional relationship of MBL for an effective structure-based drug design (SBDD). Developing new MBL inhibitors using SBDD could help address the research gap and provide new successful therapeutic options for treating MBL-producing bacterial infections.

Bibliometric analysis and thematic review of Candida pathogenesis: Fundamental omics to applications as potential antifungal drugs and vaccines.

Invasive candidiasis caused by the pathogenic Candida yeast species has resulted in elevating global mortality. The pathogenicity of Candida spp. is not only originated from its primary invasive yeast-to-hyphal transition; virulence factors (transcription factors, adhesins, invasins, and enzymes), biofilm, antifungal drug resistance, stress tolerance, and metabolic adaptation have also contributed to a greater clinical burden. However, the current research theme in fungal pathogenicity could hardly be delineated with the increasing research output. Therefore, our study analysed the research trends in Candida pathogenesis over the past 37 years via a bibliometric approach against the Scopus and Web of Science databases. Based on the 3993 unique documents retrieved, significant international collaborations among researchers were observed, especially between Germany (Bernhard Hube) and the UK (Julian Naglik), whose focuses are on Candida proteinases, adhesins, and candidalysin. The prominent researchers (Neils Gow, Alistair Brown, and Frank Odds) at the University of Exeter and the University of Aberdeen (second top performing affiliation) UK contribute significantly to the mechanisms of Candida adaptation, tolerance, and stress response. However, the science mapping of co-citation analysis performed herein could not identify a hub representative of subsequent work since the clusters were semi-redundant. The co-word analysis that was otherwise adopted, revealed three research clusters; the cluster-based thematic analyses indicated the severeness of Candida biofilm and antifungal resistance as well as the elevating trend on molecular mechanism elucidation for drug screening and repurposing. Importantly, the in vivo pathogen adaptation and interactions with hosts are crucial for potential vaccine development.

International research collaborations have evident its significance in impactful work covering all aspects of Candida pathogenicity. Its current, diverse research was discussed thematically based on the comprehensive scientometric analysis with unidentified hub representatives for subsequent work.

An Epidemiology Study of Adult Immune Thrombocytopenia Patients in a Teaching Hospital in Northeastern Malaysia.

Immune thrombocytopenia (ITP) has been comprehensively studied and understood in Western Europe and various Asia-Pacific regions. However, the epidemiological and clinical-laboratory aspects of ITP in Malaysia remain limited and not well documented. Therefore, this study aims to evaluate the incidence and clinical parameters of ITP using 20-year retrospective data. Medical records for 205 consecutive adult patients with ITP between January 2000 and December 2022 were analyzed. A p-value of <0.05 is considered statistically significant. The majority were Malays (n=192, 93.7%) and females (n=150, 73.2%), with a male-to-female ratio of 1:2.73. One hundred thirty-two (64.4%) and 73 (35.6%) patients were diagnosed with primary ITP (pITP) and secondary ITP (sITP), respectively. Systemic lupus erythematosus (SLE) (n=23, 35.9%), antiphospholipid syndrome (APS) (n=5, 7.8%), and familial thrombocytopenia (n=5, 7.8%) were the top 3 comorbid conditions for ITP. The overall incidence was 1.80/100,000 person-years (95% confidence interval (CI): 1.56-2.07), and the incidences were higher in females than in males with pITP (1.78/100,000 person-years versus 0.70/100,000 person-years) and sITP (0.86/100,000 person-years versus 0.26/100,000 person-years). The median age for patients with pITP was significantly higher than for those with sITP (median: 44 versus 37 years, respectively) (p=0.026). However, there was no statistically significant difference in white blood cell (WBC) counts, hemoglobin (HB) counts, platelet (PLT) counts, absolute neutrophil counts (ANC), or hematocrit (HCT) counts between those with pITP and sITP at the time of diagnosis. The current study provides an overview of ITP epidemiology in northeastern Malaysia. We emphasize the critical need for further additional research, particularly at the state and national levels in the future.

Effects of alcohol concentration and temperature on the dynamics and stability of mutant Staphylococcal lipase.

The stability and activity of lipase in organic media are important parameters in determining how quickly biocatalysis proceeds. This study aimed to examine the effects of two commonly used alcohols in industrial applications, methanol (MtOH) and ethanol (EtOH) on the conformational stability and catalytic activity of G210C lipase, a laboratory-evolved mutant of Staphylococcus epidermidis AT2 lipase. Simulation studies were performed using an open-form predicted structure under 30, 40 and 50% of MtOH and EtOH at 25 °C and 45 °C. The overall enzyme structure becomes more flexible with increasing concentration of MtOH and exhibited the highest flexibility in 40% EtOH. In EtOH, the movement of the lid was found to be temperature-dependent with a noticeable shift in the lid position at 45 °C. Lid opening was evidenced at 50% of MtOH and EtOH which was supported by the increase in SASA of hydrophobic residues of the lid and catalytic triad. The active site remained mostly intact. An open-closed lid transition was observed when the structure was re-simulated in water. Experimental evaluation of the lipase stability showed that the half-life reduced when the enzyme was treated with 40% (v/v) and 50% (v/v) of EtOH and MtOH respectively. The finding implies that a high concentration of alcohol and elevated temperature can induce the lid opening of lipase which could be essential for the activation of the enzyme, provided that the catalytic performance in the active site is not compromised.Communicated by Ramaswamy H. Sarma.

Characteristics of ABO Antibodies in Group O Malaysian Blood Donors.

Background: Haemolytic transfusion reactions (HTRs) due to anti-A and anti-B antibodies in Group O blood products are rare but potentially fatal. This study aimed to identify the prevalence of high ABO antibody titre and the immunoglobulin (Ig) classes (IgM only or with IgG) and the prevalence of haemolysin antibodies in Group O blood donors. Methods: Plasma from Group O blood donors was tested by using antibody titration at room temperature. Titres ≥ 64 were considered high. The plasma was treated with 0.01 M dithiothreitol (DTT) to determine the presence of IgG antibodies and titre. IgG titres ≥ 64 were considered high. Tests for haemolysis were conducted by mixing the plasma with 3% fresh A1 and B cell suspensions and incubating at 37 °C. The haemolysis was observed macroscopically. Results: Of 311 donors, 238 (76.5%) showed high anti-A and/or anti-B antibody titres. The highest antibody titre obtained was 256. Female and younger donors (< 40 years old) had higher anti-A and anti-B titres. The anti-B titre showed an association with gender (P < 0.001), and was high in female donors (77.8%). Males aged over 50 years old were found to have low mean titre antibodies. Most donors had both IgM and IgG ABO antibodies. The prevalence of haemolysins in our population was 3.5%. Conclusion: Most of our O blood donors had a high ABO antibody titre but a low prevalence of haemolysins. Males aged over 50 years old are the best O donors for preventing HTRs, particularly when mismatch transfusion is required. We recommend a transfusion unit screen for ABO antibody titre in younger female donors (< 40 years old), to prevent the transfusion of high titre O blood products into non-O recipients.

Probing the substrate binding modes and catalytic mechanisms of BLEG-1, a promiscuous B3 metallo-ß-lactamase with glyoxalase II properties.

BLEG-1 from Bacillus lehensis G1 is an evolutionary divergent B3 metallo-ß-lactamase (MBL) that exhibited both ß-lactamase and glyoxalase II (GLXII) activities. Sequence, phylogeny, biochemical and structural relatedness of BLEG-1 to B3 MBL and GLXII suggested BLEG-1 might be an intermediate in the evolutionary path of B3 MBL from GLXII. The unique active site cavity of BLEG-1 that recognizes both ß-lactam antibiotics and S-D-lactoylglutathione (SLG) had been postulated as the key factor for its dual activity. In this study, dynamic ensembles of BLEG-1 and its substrate complexes divulged conformational plasticity and binding modes of structurally distinct substrates to the enzyme, providing better insights into its structure-to-function relationship and enzymatic promiscuity. Our results highlight the flexible nature of the active site pocket of BLEG-1, which is governed by concerted loop motions involving loop7+α3+loop8 and loop12 around the catalytic core, thereby moulding the binding pocket and facilitate interactions of BLEG-1 with both ampicillin and SLG. The distribution of (i) predominantly hydrophobic amino acids in the N-terminal domain, and (ii) flexible amino acids with polar and/or charged side chains in both N- and C-termini provide additional advantages to BLEG-1 in confining the aromatic group of ampicillin, and polar groups of SLG, respectively. The importance of these residues for substrates binding was further confirmed by the reduction in MBL and GLXII activities upon alanine substitutions of Ile-10, Phe-57, Arg-94, Leu-95, and Arg-159. Based on molecular dynamics simulation, mutational, and biochemical data presented herein, the catalytic mechanisms of BLEG-1 toward the hydrolysis of ß-lactams and SLG were proposed.

Platelet Additive Solutions as an Alternative Storage Medium of Apheresis Platelets to Reduce ABO Antibody Titer for ABO-Incompatibility Platelet Transfusion.

Introduction Platelet additive solutions (PASs) are nutrient media commonly used to replace and reduce the need for storage plasma. They are an alternative medium to maintain high-quality platelets lasting longer on the shelf for about seven days. Platelets with high titer of ABO antibody can pose a hemolytic transfusion reaction (HTR) risk if units are given across the ABO barrier. The risk of complication is greater when group O platelet is released to non-group O patients. The PAS has been known as a safe medium, where the titer of ABO antibodies is expected to be diluted. In this study, we compared the anti-A and anti-B antibody titers of apheresis platelets in PAS and non-PAS (plasma) as the suspending media. Methods A total of 20 apheresis platelet donors were selected, with seven from blood group A, eight from blood group B, and five from blood group O. The platelets were collected using an Amicus cell separator. They were suspended in PAS and plasma before being stored at a temperature range of 22-24º C. Anti-A (blood group B and O) and Anti-B (blood group A and O) antibody titers were measured and compared between the two suspending media. Wilcoxon signed-rank test is used for statistical analysis, and a p-value <0.05 is considered significant. Results The median titer of the anti-A antibody of apheresis platelets showed a significant difference between suspended in PAS (2.50) and plasma (4.00), p=0.002. Similar findings were also seen with the median titer of the anti-B antibody of apheresis platelet, in which it showed a significant difference between suspended in PAS (2.00) and plasma (4.00), p=0.004. It was observed that there was a significant reduction in both anti-A and anti-B antibody titers in the PAS as compared to the plasma group. Conclusion The decrease in ABO antibody titer in apheresis platelets stored with PAS can be beneficial for patients. This reduces the risk of HTRs if ABO-incompatible platelet units need to be issued. Thus, using PAS as a storage medium significantly improves platelet inventory management without compromising patient safety.

Effect of cysteine mutation at Ca2+ coordinating residues to the autolysis, folding and hydrophobicity of full length and mature Rand protease: molecular dynamics simulation and essential dynamics.

Rand protease is a serine protease that shared common characteristics with members of the MEROPS S8 subtilisin family. It is thermostable, highly stable in organic solvent and broad in specificity. Many structures of homologous protein solved by X-ray crystallography and NMR have been deposited to Protein Data Bank (PDB) which allowed this study to rely on structure prediction by deep learning to build three-dimensional (3D) structure of full length and mature Rand protease (flRP and mRP). In silico cysteine mutation to 7 predicted high affinity Ca2+ coordinating residues were introduced, and the mutants were subjected to molecular dynamics simulation to study its effect on flRP and mRP. MD simulation showed a marked increase in flexibility of the pro-peptide segment indicating the impact of single cysteine substitution at high affinity Ca2+ coordinating residues to autolysis of flRP. MD simulation for mRP reaffirmed the role of Ca2+ coordinating sites in providing stability to Rand protease. In addition, these residues also affect the autolysis, folding and hydrophobicity of RP. Essential dynamics observed large contribution of the first few eigenvectors of flRP, mRP and their high affinity Ca2+ coordinating residues mutants to the TMSF values which indicates that these values account for a large portion of the overall atomic fluctuations. These results have given a more comprehensive understanding on the role of cysteine substituted Ca2+ coordinating surface loop to the structure of flRP and mRP which are important in contributing to the structural stability of subtilisin.Communicated by Ramaswamy H. Sarma.