Publications by authors named "Vaidyula V"

Introduction: Cleaning protocols were changed in response to the COVID-19 pandemic with unknown occupational health impacts. There is evidence that COVID-19 transmission risks from contaminated surfaces are low and that exposure to cleaning products can increase risks of work-related asthma. The study objective was to investigate relationships between reported COVID-19-related changes in cleaning protocols and prevalence of asthma-related respiratory symptoms for asthmatic and non-asthmatic janitors and maids.

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Introduction: Chronic obstructive pulmonary disease (COPD) patients have increased risk for cardiovascular mortality and venous thromboembolism. Tissue factor (TF) is the physiological initiating mechanism for blood coagulation and is pro-inflammatory.

Methods: We have studied circulating blood-borne TF-procoagulant activity (TF-PCA), plasma coagulation factors (F) VIIa and FVIII, and thrombin-antithrombin (TAT) complexes in 11 stable, moderate-severe COPD patients, 10 free of exacerbation for >3 weeks.

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Alterations in blood coagulation may explain the poorer neurological outcome with diabetes mellitus and hyperglycemia after acute ischemic stroke. We studied the relationships between diabetes mellitus, hyperglycemia, whole blood tissue factor procoagulant activity (TF-PCA) and plasma factorVIIa (FVIIa) in ten patients with type 2 diabetes mellitus and 11 non-diabetic patients at baseline and 6, 12, 24, and 48 hours (h) after presentation for acute stroke. In addition, we examined plasma prothrombin fragment 1+2 (F1.

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Context: Type 2 diabetes mellitus (T2DM) is a hypercoagulable state. Tissue factor (TF) is the principal initiator of blood coagulation.

Objective: Our objective was to examine the effects of hyperglycemia and hyperinsulinemia on the TF pathway of blood coagulation in T2DM.

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The tissue factor (TF) pathway is the primary mechanism for initiation of blood coagulation. Circulating blood contains TF, which originates mainly from monocytes and is thrombogenic. The presence of somatostatin (SMS) receptors on monocytes suggests the possibility that SMS may regulate TF synthesis and/or release.

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Tissue factor (TF) is the physiological initiating mechanism for blood coagulation. Platelets play an important role in monocyte TF expression, thrombosis and inflammation. Aspirin, clopidogrel and cilostazol, which inhibit platelet responses by different mechanisms, are widely used in patients with arterial diseases.

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Unlabelled: Type 2 diabetes mellitus (T2DM) patients have hyperglycemia and hyperinsulinemia and increased risk of atherosclerosis and acute vascular complications. We have reported elevated circulating tissue factor procoagulant activity (TF-PCA) during hyperglycemia (HG) and hyperinsulinemia (HI) in normal subjects. To evaluate the effect of hyperglycemia and hyperinsulinemia on blood cell activation, we assessed platelet CD40L and P-selectin, monocyte tissue factor (TF), and the formation of monocyte-platelet and neutrophil-platelet aggregates.

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Individuals with chronically elevated glucose and/or insulin levels, i.e., most patients with type 2 diabetes, have accelerated atherosclerosis and are prone to acute vascular events.

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Thrombin responses in human platelets are mediated by the protease-activated receptors (PAR), PAR1 and PAR4. The signalling pathways mediating PAR activation have not been fully delineated for human platelets. We assessed cytoplasmic Ca2+ mobilization in response to activation with thrombin and PAR1 (SFLLRN) and PAR4 (GYPGKF) peptides in two patients whose platelets were deficient in two major signalling proteins, Galphaq or phospholipase (PLC)-beta2.

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G-proteins play an important role in platelet signal transduction and regulate responses upon activation of G-protein coupled receptors (GPCR). We have previously reported a patient with impaired platelet responses associated with deficiency in platelet Galphaq. To understand the molecular basis for this defect, the cDNA sequence encoding Galphaq (1080 bp) was obtained by reverse-transcription and polymerase chain reaction of platelet RNA; the cDNA sequence showed no mutations in the patient.

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Phospholipase C (PLC)-beta2 plays a major role in platelet activation. Previous studies have described a unique patient with impaired receptor-mediated platelet aggregation, secretion, calcium mobilization, and phospholipase C (PLC) activation associated with a selective decrease in platelet PLC-beta2 isozyme. To identify the mechanisms leading to the defect, platelet RNA from the patient and healthy subjects was subjected to reverse transcription-polymerase chain reaction (RT-PCR) and the products sequenced.

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