The value of thoracic computed tomography scan comparing to reverse transcription-polymerase chain reaction for the diagnosis of COVID-19.

BACKGROUND: Novel coronavirus disease of 2019 (COVID-19) is the current pandemic causing massive morbidity and mortality worldwide. The gold standard diagnostic method in use is reverse transcription-polymerase chain reaction (RT-PCR) which cannot be solely relied upon. Computed tomography (CT) scan is a method currently used for diagnosis of lung disease and can play a substantial role if proved helpful in COVID-19 diagnosis. We conducted this study to evaluate the diagnostic value of CT scan compared to RT-PCR in the diagnosis of COVID-19. MATERIALS AND METHODS: We recruited 291 hospitalized patients suspicious of COVID-19 according to typical clinical findings during February-March 2020. The patients underwent CT-scan and RT-PCR procedures on the day of hospital admission. CT scans were reported by two radiologists as typical, indeterminate, negative, and atypical. Statistical indices were calculated twice: once considering "typical" and "indeterminate" categories as positive and the other time counting "typical" results as positive. RESULTS: The CT reports were classified as typical (64.95%), indeterminate (10.31%), atypical (11%), and negative (13.75%). Considering "typical" and "intermediate" as positive, sensitivity and specificity were 85.3% and 38.8%, respectively, and using the second assumption, the mentioned indices were 75.9% and 50.4%, respectively. CONCLUSION: According to our study, CT results do not create enough diagnostic benefit and could result in incorrect confidence if negative. Since widely available, CT integration in the clinical process may be helpful in screening of suspected patients in epidemics. Yet, suspected patients should be isolated till confirmed by (multiple) PCRs.

Bacterial staphylokinase as a promising third-generation drug in the treatment for vascular occlusion.

Vascular occlusion is one of the major causes of mortality and morbidity. Blood vessel blockage can lead to thrombotic complications such as myocardial infarction, stroke, deep venous thrombosis, peripheral occlusive disease, and pulmonary embolism. Thrombolytic therapy currently aims to rectify this through the administration of recombinant tissue plasminogen activator. Research is underway to design an ideal thrombolytic drug with the lowest risk. Despite the potent clot lysis achievable using approved thrombolytic drugs such as alteplase, reteplase, streptokinase, tenecteplase, and some other fibrinolytic agents, there are some drawbacks, such as high production cost, systemic bleeding, intracranial hemorrhage, vessel re-occlusion by platelet-rich and retracted secondary clots, and non-fibrin specificity. In comparison, bacterial staphylokinase, is a new, small-size plasminogen activator, unlike bacterial streptokinase, it hinders the systemic degradation of fibrinogen and reduces the risk of severe hemorrhage. A fibrin-bound plasmin-staphylokinase complex shows high resistance to a2-antiplasmin-related inhibition. Staphylokinase has the potential to be considered as a promising thrombolytic agent with properties of cost-effective production and the least side effects.

The effects of doxepin on stress-induced learning, memory impairments, and TNF-α level in the rat hippocampus.

Stress has a profound impact on the nervous system and causes cognitive problems that are partly related to the inflammatory effects. Besides influencing the content of neurotransmitters, antidepressants such as doxepin are likely to have anti-inflammatory, anti-oxidative, and anti-apoptotic effects. Therefore, the present study investigated the effects of doxepin on passive avoidance learning and the levels of tumor necrosis factor-alpha (TNF-α) in the rat hippocampus following repeated restraint stress. Male Wistar rats were divided into five groups. Chronic stress was induced by keeping animals within an adjustable restraint chamber for 6 h every day for 21 successive days. In stress-doxepin group, stressed rats were given 1, 5 and 10 mg/kg of doxepin intraperitoneally (i.p) for 21 days and before placing them in restraint chamber. Healthy animals who served as control group and stressed rats received normal saline i.p. For evaluation of learning and memory, initial latency and step-through latency were determined using passive avoidance learning test. TNF-α levels were measured in hippocampus by enzyme-linked immunosorbant assay (ELISA) at the end of experiment. Induced stress considerably decreased the step through latencies in the rats (P<0.05) but doxepin administration prevented these changes. Stress-doxepin groups did not reveal any differences compared to control group at any given doses. TNF-α level was increased significantly (P<0.05) in stress group. Only the low dose of doxepin (1 mg/kg) decreased TNF-α level. The present findings indicated that learning and memory are impaired in stressful conditions and doxepin prevented memory deficit. It seems that inflammation may involve in induced stress memory deficits, and that doxepin is helpful in alleviating the neural complications due to stress.

Effects of amitriptyline and fluoxetine on synaptic plasticity in the dentate gyrus of hippocampal formation in rats.

BACKGROUND: Several studies have been shown that antidepressant drugs have contradictory effects on cognitive processes. Therefore, the aim of this study was to investigate the effects of amitriptyline and fluoxetine on synaptic plasticity in the dentate gyrus (DG) of the hippocampal formation in rat. MATERIALS AND METHODS: Experimental groups were the control, the fluoxetine, and amitriptyline. The rats were treated for 21 days and then, paired pulse facilitation/inhibition (PPF/I) and long-term potentiation (LTP) in perforant path-DG synapses were assessed (by 400 Hz tetanization). Field excitatory post-synaptic potential (fEPSP) slope and population spike (PS) amplitude were measured. RESULTS: The results of PPF/I showed that PS amplitude ratios were increased in 10-70 ms inter-stimulus intervals in the amitriptyline group compared to the control group. In the fluoxetine group, EPSP slope ratios were decreased in intervals 30, 40, and 50 ms inter-stimulus intervals compared to the control group. The PS-LTP was significantly lower in the fluoxetine and the amitriptyline groups with respect to the control group. CONCLUSION: The results showed that fluoxetine and amitriptyline affect synaptic plasticity in the hippocampus and these effects is probably due to the impact on the number of active neurons.

Lowering effect of valsartan on fetuin-A in type 1 diabetes mellitus.

INTRODUCTION: Fetuin-A (A2-HS-glycoprotein) is a protein that plays several functions in human physiology and pathophysiology. The role of fetuin-A in type 1 diabetes mellitus (DM) has been less studied. We investigated the serum levels of fetuin-A in type 1 diabetic patients with microalbuminuria. Furthermore, the blocking effect of renin-angiotensin-aldosteron system on serum levels of fetuin-A was assessed. MATERIALS AND METHODS: From January 2010 to May 2011, 32 patients with type 1 DM with confirmed microalbuminuria were included in this study in Isfahan, Iran. Serum fetuin-A levels before and 8 weeks after valsartan administration were measured. In addition, serum lipid profile, creatinine, hemoglobin A1c, and urine microalbuminuria were determined. RESULTS: The mean age of participants was 21.65 +/- 0.38 years. Before valsartan administration, the mean values of fetuin-A were not significantly different between males and females (64.22 +/- 1.77 ng/mL versus 61.39 +/- 3.35 ng/mL, respectively). After valsartan administration, serum levels of fetuin-A and urine albumin-creatinine significantly decreased. A negative correlation was observed between serum fetuin-A level after valsartan administration and serum low-density lipoprotein cholesterol level (P = .007, r = -0.507). CONCLUSIONS: Administration angiotensin receptor blockers concomitantly decreases fetuin-A levels and urine albumin levels.