Anti-beta2 glycoprotein 1 and the anti-phospholipid syndrome

PURPOSE: To describe a patient who presented with bilateral retinal vascular occlusion and the use of anti-beta2 glycoprotein 1 (GPI) antibody testing in the diagnosis of antiphospholipid syndrome. DESIGN: Observational case report. METHODS: Hematological investigations were performed on a 49-year-old man who presented with rapid onset of bilateral severe central retinal vein occlusion. RESULTS: Lupus anticoagulant and anticardiolipin antibody testing was negative. Markedly raised titers of anti-beta2 GPI antibodies were detected on two separate occasions. CONCLUSIONS: The raised titers of anti-beta2 GPI antibodies were considered to strongly suggest an underlying diagnosis of the antiphospholipid syndrome.     

Oxidized low-density lipoprotein and intimal medial thickness in subjects with glucose intolerance: the Chennai Urban Rural Epidemiology Study-25

The aim of the present study was to assess the association of oxidized low-density lipoprotein (OX-LDL) with carotid intimal medial thickness (IMT) in different grades of glucose intolerance in Asian Indians. Three groups were recruited from the Chennai Urban Rural Epidemiology Study, a population-based study: group 1, normal glucose tolerance (NGT) (n = 175); group 2, impaired glucose tolerance (IGT) (n = 175); and group 3, type 2 diabetes mellitus (n = 175). Oxidized LDL (enzyme-linked immunosorbent assay) and carotid IMT (high-resolution B-mode ultrasonography) were assessed. Subjects with diabetes had higher IMT values (0.85 +/- 0.30 mm) compared with those who have IGT (0.79 +/- 0.16 mm, P < .05) and NGT (0.71 +/- 0.12 mm, P < .001). Subjects with diabetes (40.1 +/- 13.1 U/L) and IGT (34.3 +/- 12.8 U/L) had significantly higher mean OX-LDL values compared with the NGT group (26.2 +/- 16.6 U/L, P < .001). Oxidized LDL showed a correlation with IMT (total population: r = 0.294, P < .001; subjects with NGT: r = 0.444, P < .001; and subjects with IGT: r = 0.481, P < .001). In multiple linear regression analysis, OX-LDL showed a strong association with IMT (beta = .005, P < .001), even after adjusting for age, sex (beta = .003, P < .001), and glucose intolerance (beta = .002, P < .001). In conclusion, OX-LDL levels increase with increasing glucose intolerance. Oxidized LDL is associated with carotid IMT and this is independent of age, sex, and glucose intolerance status.     

High sustained virologic response in genotypes 3 and 6 with generic NS5A inhibitor and sofosbuvir regimens in chronic HCV in myanmar

Exclusive HCV therapy clinical trials with genotype 6 patients in high prevalence areas have been sparse. We analysed the safety and efficacy of two generic, pangenotypic NS5A/NS5B combination oral DAA regimens, primarily in genotypes 3 and 6, in a real‐world setting: (a) daclatasvir/sofosbuvir (DCV/SOF) ± ribavirin (RBV) and (b) Velpatasvir/sofosbuvir (VEL/SOF ± RBV). Between December 2015 and November 2017, data from 522 patients were analysed, 311 of whom were treated with DCV/SOF ± RBV for 12/24 weeks (genotype 3: n = 193, genotype 6: n = 89) and 211 were treated with VEL/SOF ± RBV for 12/24 weeks (genotype 3: n = 83, genotype 6: n = 77). Overall SVR rates were high for both DCV/SOF ± RBV (96.1%, n = 299/311) and VEL/SOF ± RBV (95.3%, n = 201/211), and there was a good adverse event profile. Treatment naïve status and inclusion of RBV (in advanced fibrosis/cirrhosis) were significant independent predictors of achieving SVR12, while type of DAA regimen was not predictive. In this large cohort of genotypes 3 (n = 276) and 6 (n = 166; n = 127 unique subtype of 6c‐l), high SVR rates of 94.9% (n = 262/276) and 95.2% (n = 158/166), respectively, were noted. In conclusion, generic and pangenotypic DCV/SOF and VEL/SOF ± RBV regimens were highly effective and safe, in genotypes 3 and 6 chronic HCV in Myanmar. These efficacious pangenotypic regimens suggest that baseline genotype testing can be eliminated moving forward. While RBV may still be needed for those with advanced fibrosis/cirrhosis, in a global elimination strategy it would not be practical even if it does compromise SVR in a minority with difficult to treat characteristics.     

Epithelial maturity influences EPEC-induced desmosomal alterations

Desmosomes are junctional protein complexes that confer strong adhesive capacity to adjacent host cells. In a recent study, we showed that enteropathogenic Escherichia coli (EPEC) disrupts desmosomes, weakens cell-cell adhesion and perturbs barrier function of intestinal epithelial (C2_BBe) cells. Desmosomal damage was dependent on the EPEC effector protein EspH and its inhibitory effect on Rho GTPases. EspH-mediated Rho inactivation resulted in retraction of keratin intermediate filaments and degradation of desmosomal cadherins. Immunofluorescence studies of EPEC-infected C2_BBe cells revealed keratin retraction towards the nucleus coincident with significant cytoplasmic redistribution of the desmosomal cadherin desmoglein-2 (DSG2). In this addendum, we expand on how EPEC-induced keratin retraction leads to loss of DSG2 anchoring at the junctions, and show that maturity of the epithelial cell monolayer impacts the fate of desmosomes during infection.     

Production of murine monoclonal antibody to fetal hemoglobin

Fetal hemoglobin (Hb F) is a major hemoglobin (Hb) component at birth. Hb F levels are markedly elevated in a number of inherited and acquired disorders. Measurement of Hb F levels is usually carried out by alkali denaturation which is not very accurate for low and high values. An accurate estimation of Hb F, and also of F cells, is desired in many hematological disorders like sickle cell disease, in monitoring the efficacy of hydroxyurea (HU) therapy, to assess feto-maternal hemorrhage (FMH) during pregnancy and in the postpartum period. We have raised a murine monoclonal antibody to human Hb F, that accurately measures the number of F cells by flow cytometry. The antibody was found to be potent and specific for F cells.     

Computed tomographic angiography in tetralogy of Fallot

Echocardiography is often inadequate for imaging tetralogy of Fallot, prompting cineangiography. This study prospectively evaluated multidetector computed tomographic angiography for preoperative evaluation of tetralogy of Fallot in 112 consecutive patients. Forty-eight had nonconfluent or hypoplastic pulmonary arteries (mean z-score, -2; range, -11.1-0.13) permitting only palliative or no surgery; 64 had adequate pulmonary artery anatomy (mean z-score, 0.59; range, -2.53-3.4) allowing total repair. The surgical data of 50 patients who underwent total correction were compared with transthoracic echocardiography and multidetector computed tomographic angiography findings. Multidetector computed tomographic angiography tended to reveal unsuspected collaterals and coronary abnormalities besides outlining the right ventricular outflow tract and pulmonary artery branches. The branch pulmonary artery diameter z-score was the most important determinant of surgical strategy, with the worst figures being associated with no surgical options or palliative surgery, and the best figures leading to corrective surgery. The mean radiation dose was 3.45 mSv. Multidetector computed tomographic angiography is a powerful supplement to echocardiography in the preoperative evaluation of tetralogy of Fallot.     

Dysmetabolic hyperferritinemia is associated with normal transferrin saturation,mild hepatic iron overload,and elevated hepcidin

Hyperferritinemia is common in individuals with the metabolic syndrome (dysmetabolic hyperferritinemia), but its pathophysiology and the degree to which it reflects tissue iron overload remains unclear. We conducted a cross-sectional study evaluating ten cases with dysmetabolic hyperferritinemia for liver iron overload and compared their serum iron indices and urine hepcidin levels to healthy controls. Seven out of ten cases had mild hepatic iron overload by magnetic resonance imaging (MRI) (median, 75 μmol/g dry weight). Cases had higher serum ferritin than controls (median, 672 μg/L vs. 105 μg/L, p < 0.001), but the median transferrin saturation was not significantly different (38% vs. 36%, p = 0.5). Urinary hepcidin was elevated in dysmetabolic hyperferritinemia (median; 1,584 ng/mg of creatinine vs. 799 ng/mg of creatinine, p = 0.05). Dysmetabolic hyperferritinemia is characterized by hyperferritinemia with normal transferrin saturation, elevated hepcidin levels, and mild liver iron overload in a subset of patients.     

H2S mediates O2 sensing in the carotid body

Gaseous messengers, nitric oxide and carbon monoxide, have been implicated in O₂ sensing by the carotid body, a sensory organ that monitors arterial blood O₂ levels and stimulates breathing in response to hypoxia. We now show that hydrogen sulfide (H₂S) is a physiologic gasotransmitter of the carotid body, enhancing its sensory response to hypoxia. Glomus cells, the site of O₂ sensing in the carotid body, express cystathionine γ-lyase (CSE), an H₂S-generating enzyme, with hypoxia increasing H₂S generation in a stimulus-dependent manner. Mice with genetic deletion of CSE display severely impaired carotid body response and ventilatory stimulation to hypoxia, as well as a loss of hypoxia-evoked H₂S generation. Pharmacologic inhibition of CSE elicits a similar phenotype in mice and rats. Hypoxia-evoked H₂S generation in the carotid body seems to require interaction of CSE with hemeoxygenase-2, which generates carbon monoxide. CSE is also expressed in neonatal adrenal medullary chromaffin cells of rats and mice whose hypoxia-evoked catecholamine secretion is greatly attenuated by CSE inhibitors and in CSE knockout mice.     

Chloroquine sensitizes biofilms of Candida albicans to antifungal azoles

Biofilms formed by Candida albicans, a human pathogen, are known to be resistant to different antifungal agents. Novel strategies to combat the biofilm associated Candida infections like multiple drug therapy are being explored. In this study, potential of chloroquine to be a partner drug in combination with four antifungal agents, namely fluconazole, voriconazole, amphotericin B, and caspofungin, was explored against biofilms of C. albicans. Activity of various concentrations of chloroquine in combination with a particular antifungal drug was analyzed in a checkerboard format. Growth of biofilm in presence of drugs was analyzed by XTT-assay, in terms of relative metabolic activity compared to that of drug free control. Results obtained by XTT-metabolic assay were confirmed by scanning electron microscopy. The interactions between chloroquine and four antifungal drugs were determined by calculating fractional inhibitory concentration indices. Azole resistance in biofilms was reverted significantly (p < 0.05) in presence of 250 μg/mL of chloroquine, which resulted in inhibition of biofilms at very low concentrations of antifungal drugs. No significant alteration in the sensitivity of biofilms to caspofungin and amphotericin B was evident in combination with chloroquine. This study for the first time indicates that chloroquine potentiates anti-biofilm activity of fluconazole and voriconazole.     

In vitro antiplasmodial effect of ethanolic extracts of traditional medicinal plant Ocimum species against Plasmodium falciparum

ObjectiveTo identify the possible antiplasmodial compounds from leaf, stem, root and flower extracts of Ocimum canum (O. canum), Ocimum sanctum (O. sanctum) and Ocimum basilicum (O. basilicum).MethodsThe O. canum, O. sanctum and O. basilicum were collected from Ramanathapuram District, Tamil Nadu and the extraction was carried out in ethanol. The filter sterilized extracts (100, 50, 25, 12.5, 6.25 and 3.125 μg/mL) of leaf, stem, root and flower extracts of O. canum, O. sanctum and O. basilicum were tested for antiplasmodial activity against Plasmodium falciparum (P. falciparum). The potential extracts were also tested for their phytochemical constituents.ResultsThe leaf extract of O. sanctum showed excellent antiplasmodial activity (IC₅₀ 35.58 μg/mL) followed by leaf extract of O. basilicum (IC₅₀ 43.81 μg/mL). The leaf extract of O. canum, root extracts of O. sanctum and O. basilicum, the stem and flower extracts of all the three tested Ocimum species showed IC₅₀ values between 50 and 100 μg/mL. Statistical analysis reveals that, significant antiplasmodial activity (P <0.01) was observed between the concentrations and time of exposure. The chemical injury to erythrocytes was also carried out and it shows that, there were no morphological changes in erythrocytes by the ethanolic extract of O. canum, O. sanctum and O. basilicum. The in vitro antiplasmodial activity might be due to the presence of alkaloids, glycosides, flavonoids, phenols, saponins, triterpenoids, proteins, resins, steroids and tannins in the ethanolic extracts of tested plants.ConclusionsThe ethanolic leaf extracts of O. sanctum possess lead compounds for the development of antiplasmodial drugs.