MUTATION ANALYSIS OF INDONESIAN MENTALLY RETARDED INDIVIDUALS WITH MICROCEPHALY AND MACROCEPHALY

Background Among the mentally retarded individuals, associated features are often found that may lead to specific diagnosis, such as microcephaly or macrocephaly. Mutations in the autosomal recessive primary hereditary microcephaly (MCPH) genes are known to cause mental retardation (MR) and microcephaly, while mutations in the PTEN gene cause MR and macrocephaly. This study aims to analyse the presence of mutations in the Indonesian individuals with MR and microcephaly or macrocephaly. Methods From a previous study of 527 mentally retarded individuals, 48 microcephalic and 10 macrocephalic individuals underwent DNA sequencing. Secondary data from a previous study was used to determine the head circumference based on the Nellhaus head charts. The DNA of the microcephalic subjects was analysed for mutations of the MCPH genes while PTEN DNA sequencing were performed on macrocephalic subjects. The likelihood of pathogenicity of the variants found was determined by comparing them to mutation database and analysis of protein prediction programs of SIFT, Align-GVGD and Polyphen-2. Results From 48 individuals with MR and microcephaly, 23 variants on the MCPH genes were found as likely to be pathogenic, while no pathogenic mutation was found. One subject was found to have 2 variants which were predicted as likely to be pathogenic and underwent follow up, in which a monozygotic twin with the same 2 variants was discovered to be unaffected, revealing twin discordance result. None of the 10 subjects with macrocephaly and MR had any mutations in the PTEN gene. Conclusion Microcephaly was present in 9.1% of 527 individuals with MR, while macrocephaly occured in 1.9%. This study did not find any pathogenic causative mutation in the MCPH genes as well as PTEN gene that underwent DNA sequencing. This might be due to the non-genetic cause of microcephaly or macrocephaly and MR or mutations that were not yet discovered in this study. Interestingly, one twins discordance result was found. The findings of MR associated with microcephaly and macrocephaly may aid in providing genetic counseling in the Indonesian setting. Keywords : Mental retardation, microcephaly, macrocephaly, PTEN, MCP

The effects of signal transducer and activator of transcription three mutations on human platelets

Involvement of signal transducer and activator of transcription 3 (STAT3) in inflammation is well known. Recently, a role for STAT3 in platelet activation and platelet production has been suggested. Platelets exhibit important immune functions and engagement of STAT3 in platelet physiology may link inflammation and hemostasis. This study investigated the effects of STAT3 loss-of-function mutations and single nucleotide polymorphisms (SNPs) in STAT3 on glycoprotein VI (GPVI)-mediated platelet activation and platelet numbers in humans. Two cohorts were studied. The first cohort concerned patients with STAT3 loss-of-function mutations. Platelet numbers were investigated in eight patients and GPVI-mediated platelet activation was functionally tested in four patients. Additional experiments were performed to investigate underlying mechanisms. The second cohort concerned 334 healthy volunteers and investigated the consequences of SNPs in STAT3 on GPVI-mediated platelet activation and platelet numbers. Platelet activation was lower in STAT3 loss-of-function patients at baseline and after stimulation of the GPVI receptor, reflected by decreased P-selectin expression. This was independent of gene transcription. Blockade of the adenosine di-phosphate (ADP) pathway resulted in a further decrease of P-selectin expression, particularly in STAT3 loss-of-function patients. In contrast, the SNPs in STAT3 did not influence GPVI-mediated platelet activation. Also, platelet numbers were not affected by STAT3 loss-of-function mutations, nor was there an association with the SNPs. In conclusion, STAT3 signaling does not seem to play a major role in thrombopoiesis. We confirm that STAT3 is involved in GPVI-mediated platelet activation in humans, independent of gene transcription. GPVI-mediated platelet activation is highly dependent on secondary ADP release. Our findings suggest that STAT3 modulation may affect inflammation, hemostasis, and their interaction.</p

Phage-derived protein induces increased platelet activation and is associated with mortality in patients with invasive pneumococcal disease

To improve our understanding about the severity of invasive pneumococcal disease (IPD), we investigated the association between the genotype of Streptococcus pneumoniae and disease outcomes for 349 bacteremic patients. A pneumococcal genome-wide association study (GWAS) demonstrated a strong correlation between 30-day mortality and the presence of the phage-derived gene pblB, encoding a platelet-binding protein whose effects on platelet activation were previously unknown. Platelets are increasingly recognized as key players of the innate immune system, and in sepsis, excessive platelet activation contributes to microvascular obstruction, tissue hypoperfusion, and finally multiorgan failure, leading to mortality. Our in vitro studies revealed that pblB expression was induced by fluoroquinolones but not by the beta-lactam antibiotic penicillin G. Subsequently, we determined pblB induction and platelet activation by incubating whole blood with the wild type or a pblB knockout mutant in the presence or absence of antibiotics commonly administered to our patient cohort. pblB-dependent enhancement of platelet activation, as measured by increased expression of the ɑ-granule protein P-selectin, the binding of fibrinogen to the activated ɑ IIbβ3 receptor, and the formation of platelet-monocyte complex occurred irrespective of antibiotic exposure. In conclusion, the presence of pblB on the pneumococcal chromosome potentially leads to increased mortality in patients with an invasive S. pneumoniae infection, which may be explained by enhanced platelet activation. This study highlights the clinical utility of a bacterial GWAS, followed by functional characterization, to identify bacterial factors involved in disease severity. IMPORTANCE The exact mechanisms causing mortality in invasive pneumococcal disease (IPD) patients are not completely understood. We examined 349 patients with IPD and found in a bacterial genome-wide association study (GWAS) that the presence of the phage-derived gene pblB was associated with mortality in the first 30 days after hospitalization. Although pblB has been extensively studied in Streptococcus mitis, its consequence for the interaction between platelets and Streptococcus pneumoniae is largely unknown. Platelets are important in immunity and inflammation, and excessive platelet activation contributes to microvascular obstruction and multiorgan failure, leading to mortality. We therefore developed this study to assess whether the expression of pblB might increase the risk of death for IPD patients through its effect on enhanced platelet activation. This study also shows the value of integrating extensive bacterial genomics and clinical data in predicting and understanding pathogen virulence, which in turn will help to improve prognosis and therapy

Black Fungus Complicated with COVID-19 in a Man with Underlying Non-Hodgkin’s Lymphoma

COVID-19 is a disease reported to suppress cellular immunity. This may lead to the development of opportunistic infections, among others black fungus, or mucormycosis. On the other hand, pre-existing defect in immunity may render patients susceptible to both mucormycosis and COVID-19. Mucormycosis is a relatively rare fungal infection with rapid progression unless diagnosed promptly and treated adequately, and urgent surgical and medical intervention is lifesaving. The manifestation of mucormycosis largely depends on the presence of exposure to the pathogen and the existing risk factor of the host. As black fungus is locally invasive, the majority of cases will involve tissue damage with local destruction and contiguous spread to nearby structure. We here with present a case of black fungus complicated with COVID-19 in a man with underlying non-Hodgkin’s lymphoma

Platelet dysfunction contributes to bleeding complications in patients with probable leptospirosis

Contains fulltext : 177417.pdf (publisher's version ) (Open Access)BACKGROUND: Severe leptospirosis is frequently complicated by a hemorrhagic diathesis, of which the pathogenesis is still largely unknown. Thrombocytopenia is common, but often not to the degree that spontaneous bleeding is expected. We hypothesized that the hemorrhagic complications are not only related to thrombocytopenia, but also to platelet dysfunction, and that increased binding of von Willebrand factor (VWF) to platelets is involved in both platelet dysfunction and increased platelet clearance. METHODOLOGY/PRINCIPAL FINDINGS: A prospective study was carried out in Semarang, Indonesia, enrolling 33 hospitalized patients with probable leptospirosis, of whom 15 developed clinical bleeding, and 25 healthy controls. Platelet activation and reactivity were determined using flow cytometry by measuring the expression of P-selectin and activation of the alphaIIbbeta3 integrin by the binding of fibrinogen in unstimulated samples and after ex vivo stimulation by the platelet agonists adenosine-diphosphate (ADP) and thrombin-receptor activating peptide (TRAP). Platelet-VWF binding, before and after VWF stimulation by ristocetin, as well as plasma levels of VWF, active VWF, the VWF-inactivating enzyme ADAMTS13, thrombin-antithrombin complexes (TAT) and P-selectin were also measured. Bleeding complications were graded using the WHO bleeding scale. Our study revealed that platelet activation, with a secondary platelet dysfunction, is a feature of patients with probable leptospirosis, especially in those with bleeding manifestations. There was a significant inverse correlation of bleeding score with TRAP-stimulated P-selectin and platelet-fibrinogen binding (R = -0.72, P = 0.003 and R = -0.66, P = 0.01, respectively) but not with platelet count. Patients with bleeding also had a significantly higher platelet-VWF binding. Platelet counts were inversely correlated with platelet-VWF binding (R = -0.74; P = 0.0009. There were no correlations between platelet-VWF binding and the degree of platelet dysfunction, suggesting that increased platelet-VWF binding does not directly interfere with the platelet alphaIIbbeta3 signaling pathway in patients with probable leptospirosis. CONCLUSION/SIGNIFICANCE: Platelet dysfunction is common in probable leptospirosis patients with manifest bleeding. Increased VWF-platelet binding may contribute to the activation and clearance of platelets

Hospital-acquired Skin and Skin-structure Infection in COVID-19 Infected Patient with Prolonged Hospitalization

Acute bacterial skin and skin-structure infections (ABSSSI) is defined in 2013 by the US Food and Drug Administration as a bacterial cellulitis/erysipelas, major skin abscesses, and wound infections. The Infectious Diseases Society of America (IDSA) in 2014 classifies skin and soft-tissue infection (SSTI) as either non-purulent (which includes cellulitis, erysipelas, and necrotizing infection) or purulent (including furuncle, carbuncle, and abscess). Among hospitalized patients with SSTI, healthcare-associated infections account for 73.5% of all cases. Notably, skin and skin-structure infections caused by Pseudomonas aeruginosa, a common hospital pathogen, was reported to cause higher total cost and longer hospital length of stay compared to non-P. aeruginosa cases, despite causing only approximately 5.7% of all healthcare-associated SSTIs. Infection with P. aeruginosa should always be considered in non-healing skin infections in patients with prolonged hospitalization and antibiotic exposure. Tissue culture, preferably taken by surgical debridement, should be promptly performed; and when hospital-infection is suspected, appropriate antibiotics should be started along with removal of all devitalized tissue and to promote skin and soft tissue healing. Expedited discharge should be considered when possible, with adequate antibiotic treatment and follow up for definitive wound treatment

Extrapulmonary Manifestations COVID-19

After being declared as a pandemic on March 11, 2020 by the World Health Organization, COVID-19 has affected 497 million people worldwide as of 9 April 2022. COVID-19 is a disease with a plethora of clinical manifestations, which extends to those beyond pulmonary signs and symptoms. Studies that report on the clinical presentation of COVID-19 rarely report specifically on cases with only extrapulmonary manifestations of COVID-19. Extrapulmonary clinical presentations of COVID-19 without pulmonary signs and symptoms is rare, and in such cases, COVID-19 is rarely suspected.We herewith describe four patients with extrapulmonary manifestations of COVID-19, with positive SARS-COV-2 PCR when the test was performed for initial patient screening. The first patient is a 44-year-old female who developed painful ulcer with burning sensation at the lateral side of the tongue along with low grade fever. This symptom appeared after the initial complaints of coughing and nasal congestion subsided.  The second patient is a 37-year-old male, who complained of red eyes  with itchiness and increased tear production for 3 days before seeing an ophthalmologist. The third patient is a 44-year-old female who developed burning sensation and soreness on her throat upon swallowing with fever and chills. These symptoms appear consecutively without any respiratory complaint. The fourth patient is a previously healthy, 30-year-old female, with a normal weight and BMI, and without any comorbidity, cardiovascular risk and neither personal nor family history of cardiovascular disease. In these 4 patients, COVID-19 stomatitis, conjunctivitis, pharyngitis and COVID-19-associated atrial fibrillation was subsequently diagnosed, respectively.In the pandemic stage of COVID-19, COVID-19 screening has often been routinely performed due to the high risk of transmission. However, the decrease in the number of COVID-19 cases may prompt physicians to perform SARS-COV-2 testing based on clinical suspicion. It is imperative to consider the likelihood of COVID-19 and perform SARS-COV-2 PCR in patients with extrapulmonary complaints that have persisting complaints despite treatment

Parenteral and Oral Anticoagulant Treatment for Hospitalized and Post-Discharge COVID-19 Patients: A Systematic Review and Meta-Analysis

Background: The use of anticoagulants has been endorsed by different hematological societies as coagulation abnormalities are key features of COVID-19 patients. This systematic review and meta-analysis aims to provide the most recent update on available evidence on the clinical benefits and risk of oral and parenteral anticoagulants, as well agents with anticoagulant properties, in hospitalized and post-discharge COVID-19 patients. Methods: This systematic review synthesizes data on the outcome of anticoagulation in hospitalized and post-discharge COVID-19 patients. Dichotomous variables from individual studies were pooled by risk ratio (RR) and their 95% confidence interval (95% CI) using the random-effects model. Meta-analyses were performed when feasible. Results: We included 32 studies from 2.815 unique citations, including 7 randomized clinical trials. A total of 33.494 patients were included. Outcomes measured include mortality and survival rates, the requirement for ICU care and mechanical ventilation. A pooled meta-analysis favors anticoagulant compared to no anticoagulant with reduced mortality in hospitalized patients (RR 0,55; 95%CI 0,43-0,66; p<0,001). Higher dose of anticoagulant also showed treatment benefit compared to standard prophylactic dose in selected populations (RR 0,68; 95%CI 0,40-0,96; p<0,001). Regular, pre-hospital anticoagulation prior to hospitalization yielded mixed result. There are currently no data on the benefit of anticoagulation on post-discharge COVID-19 patients. Conclusion: Determination of the presence of thrombosis in COVID-19 is important, as therapeutic dosage of anticoagulants, rather than prophylatic dose, would be indicated in such clinical situation. Anticoagulants were found to decrease the mortality of hospitalized COVID-19. The results from this study are important in the tailored treatment of COVID-19 patients. Further studies on the need for oral anticoagulation for outpatients or post-discharge is warranted. This study has been registered in PROSPERO database (CRD42020201418)

Thrombocytopenia and Platelet Dysfunction in Acute Tropical Infectious Diseases

Item does not contain fulltextThrombocytopenia is a well-known manifestation of acute tropical infectious diseases. The role of platelets in infections has received much attention recently because of their emerging activities in modulation of inflammatory responses, host defense, and vascular integrity. However, while many studies have addressed thrombocytopenia in tropical infections, abnormalities in platelet function have been largely overlooked. This is an important research gap, as platelet dysfunction may contribute to the bleeding tendency that characterizes some tropical infections. The development of novel platelet function assays that can be used in thrombocytopenic conditions (e.g., flow cytometry assays) has contributed to important new insights in recent years. In this review, the importance of platelets in tropical infections is discussed with special emphasis on the underlying mechanisms and consequences of thrombocytopenia and platelet dysfunction in these infections. Special attention is paid to malaria, a disease characterized by microvascular obstruction in which bleeding is rare, and to infections in which bleeding is common, such as dengue, other viral hemorrhagic fevers, and the bacterial infection leptospirosis. Given the importance of platelet function abnormalities in these infections, the development of affordable assays for monitoring of platelet function in low-resource countries, as well as pharmacologic interventions to prevent or reverse platelet function abnormalities, might improve clinical care and the prognosis of these infections

The influence of hypoxia on platelet function and plasmatic coagulation during systemic inflammation in humans in vivo

Contains fulltext : 207956.pdf (publisher's version ) (Open Access