Clinical,laboratory and radiological features and outcomes of moderate to severe COVID-19 patients: A descriptive retrospective study

Objective: To describe the clinical, laboratory and radiological characteristics and outcomes of moderate-to-severe coronvirus disease 2019 (COVID-19) patients.Methods: We retrospectively analyzed 43 RT-PCR confirmed moderate-to-severe COVID-19 patients who were admitted to a tertiary care center. The primary composite outcomes were admission to intensive care unit, requirement of mechanical ventilation, and death. Results: The median age of the patients was 50 years, and 62.8％ of the patients were male. Out of 43 patients, 15 (34.88％) were categorized as severe. A total of 26 (60.47％) patients had 1 or more comorbidities [diabetes (34.88％) and hypertension (30.23％)]. The median duration from the onset of symptoms to admission was 3 days, and the most common symptoms were dyspnoea (90.7％), cough (79.07％), fever (69.77％), and body ache (46.51％). Leucopenia was presented in 14 (32.56％) patients, lymphopenia in 26 (60.47％) patients, and monocytosis in 7 (16.28％) patients. Besides, 40 (93.02％) patients had bilateral patchy nodular or interstitial infiltration on chest X-ray. The primary outcomes occurred in 20 patients (46.5％), among whom 8 required mechanical ventilation. The patients who had met the primary outcomes were older. They were prone to have at least 1 comorbidity (P=0.004), diabetes (P=0.01), hypertension, higher sequential organ failure assessment score, more tachycardia, lower SpO2, lower PaO2/FiO2, more thrombocytopenia, and more pancytopenia. Conclusions: This retrospective study identified several risk factors for poor outcomes in adults with COVID-19. In particular, older age, tachycardia, high SOFA score, low SpO2, low PaO2/FiO2, presence of comorbidities in form of diabetes and hypertension, thrombocytopenia, and pancytopenia at admission were associated with higher odds of ICU admission, a requirement of mechanical ventilation and in-hospital death.     

Hyaluronan Enhances Bone Marrow Cell Therapy for Myocardial Repair After Infarction

Hyaluronan (HA) has been shown to play an important role during early heart development and promote angiogenesis under various physiological and pathological conditions. In recent years, stem cell therapy, which may reduce cardiomyocyte apoptosis, increase neovascularization, and prevent cardiac fibrosis, has emerged as a promising approach to treat myocardial infarction (MI). However, effective delivery of stem cells for cardiac therapy remains a major challenge. In this study, we tested whether transplanting a combination of HA and allogeneic bone marrow mononuclear cells (MNCs) promotes cell therapy efficacy and thus improves cardiac performance after MI in rats. We showed that HA provided a favorable microenvironment for cell adhesion, proliferation, and vascular differentiation in MNC culture. Following MI in rats, compared with the injection of HA alone or MNC alone, injection of both HA and MNCs significantly reduced inflammatory cell infiltration, cardiomyocyte apoptosis, and infarct size and also improved cell retention, angiogenesis, and arteriogenesis, and thus the overall cardiac performance. Ultimately, HA/MNC treatment improved vasculature engraftment of transplanted cells in the infarcted region. Together, our results indicate that combining the biocompatible material HA with bone marrow stem cells exerts a therapeutic effect on heart repair and may further provide potential treatment for ischemic diseases.     

Typical atrial flutter can effectively be treated using single one-minute cryoapplications: Results from a repeat electrophysiological study

Purpose  

Catheter-based cryoablation (cryo) has proven to be as effective as radiofrequency energy (RF) ablation for the treatment of arrhythmias. Nevertheless, the duration of cryoapplications has been reported as being significantly longer than RF applications.     

Modified guanidinium thiocyanate method for human sperm DNA isolation

Mammalian sperm chromatin is highly condensed, so isolating DNA from such chromatin can be a formidable task. The procedures that produce high quality DNA from somatic cells fail to yield quality sperm DNA. In this study we have modified the previously used guanidinium method to make it simple and efficient in isolating human sperm DNA. In our method, the lysis buffer contained guanidinium, sodium citrate, sarkosyl, proteinase K and mercaptoethanol. Proteinase K was not used in the original guanidinium method but was included in our protocol. CsCl centrifugation of the lysate, as described in the original procedure, was omitted. Instead, isopropyl alcohol was added directly to the lysis buffer to harvest the DNA. This modified guanidinium method generated high molecular weight DNA while the other two methods resulted in considerable DNA degradation. There was no difficulty in restriction enzyme digestion of DNA prepared by the modified method as revealed by Southern blot analysis. Since the modified guanidinium method is a simple one-step procedure which avoids homogenization, organic solvents, centrifugation and, more importantly, produces degradation-free DNA, it could be the method of choice when DNA from mature germ cells is needed.      

Thymus dysfunction and chronic inflammatory disease in gp39 transgenic mice

Expression of gp39 on activated T cells provides a co-stimulatory signal in peripheral lymphoid tissue that regulates humoral and cell- mediated immunity. The function of gp39 and its receptor CD40 in thymus remains uncertain. Here we report that overexpression of gp39 in transgenic mouse thymus caused a dose-dependent decline in thymocyte numbers (> 500 fold), loss of cortical epithelium and expansion of CD40+ medullary cells. Transplantation of transgenic bone marrow into normal mice indicated that gp39 significantly diminished thymocyte viability in the context of a 'normal' thymic environment. The peripheral tissues of transgenic mice also accumulated abnormalities in a transgene dose-dependent manner that involved inflammation and lymphoid tissue hypertrophy. Animals with the highest transgene copy numbers acquired a lethal inflammatory bowel disease marked by the infiltration of gp39+ T cells and CD40+ cells into diseased tissues. Examination of cells overexpressing gp39 suggested that these defects were caused, in part, by the saturation of a mechanism that sequesters gp39 inside non-activated cells and thus protects the immune system from inappropriate gp39-CD40 interaction. These results establish a regulatory role for gp39 in thymus function and a causal relationship in mediating chronic inflammatory disease.      

The manipulation of circadian rhythms

In a study on male Wistar (TNO) rats kept under phase-shifted light-dark (1212) conditions, it was demonstrated that the circadian rhythms of the following functions were effectively synchronized to the new lighting regimen: (a) body temperature, gross motor activity (after 1 week of acclimatization); (b) stomach weight, liver weight, liver glycogen, liver protein and acid phosphatase activity; serum corticosterone, glucose, total protein and inorganic phosphate (after 4–6 weeks; as concluded from the data pooled of a set of identical experiments); (c) the in vivo toxicity of LD₅₀ amounts (i.p.) for antimycin A and of E 600. In the individual experiments the various normal functions appeared to be different with respect to sensitivity to light. The overall pooled results indicated that, except for glycogen, the 24-h means of the normal values in the stomach, liver and serum were slightly decreased when compared to the respective means obtained from standard LD (= light: 6:00–18:00) -conditioned control groups (P < 0.001 for liver weight, liver protein, serum protein and inorganic phosphate). The experimental animals revealed an intermediate or persisting decrease of the growth rate. From the serial biological and toxicological studies performed in the course of 1 year, it is concluded that the synchronizing effect of an altered lighting regimen may be influenced by seasonal factors.Under certain conditions the use of light-manipulated animals will prove to be a useful tool in chronobiology and chronotoxicology.Supported by grants from Deutsche Forschungsgemeinschaft, Sonderforschungsbereich 146 (Versuchstierkunde) and VW-Stiftung, Hannover AZ 11.2000     

Comparison of tumor volumes derived from glucose metabolic rate maps and SUV maps in dynamic 18F-FDG PET.

Tumor delineation using noninvasive medical imaging modalities is important to determine the target volume in radiation treatment planning and to evaluate treatment response. It is expected that combined use of CT and functional information from 18F-FDG PET will improve tumor delineation. However, until now, tumor delineation using PET has been based on static images of 18F-FDG standardized uptake values (SUVs). 18F-FDG uptake depends not only on tumor physiology but also on blood supply, distribution volume, and competitive uptake processes in other tissues. Moreover, 18F-FDG uptake in tumor tissue and in surrounding healthy tissue depends on the time after injection. Therefore, it is expected that the glucose metabolic rate (MRglu) derived from dynamic PET scans gives a better representation of the tumor activity than does SUV. The aim of this study was to determine tumor volumes in MRglu maps and to compare them with the values from SUV maps. METHODS: Twenty-nine lesions in 16 dynamic 18F-FDG PET scans in 13 patients with non-small cell lung carcinoma were analyzed. MRglu values were calculated on a voxel-by-voxel basis using the standard 2-compartment 18F-FDG model with trapping in the linear approximation (Patlak analysis). The blood input function was obtained by arterial sampling. Tumor volumes were determined in SUV maps of the last time frame and in MRglu maps using 3-dimensional isocontours at 50% of the maximum SUV and the maximum MRglu, respectively. RESULTS: Tumor volumes based on SUV contouring ranged from 1.31 to 52.16 cm3, with a median of 8.57 cm3. Volumes based on MRglu ranged from 0.95 to 37.29 cm3, with a median of 3.14 cm3. For all lesions, the MRglu volumes were significantly smaller than the SUV volumes. The percentage differences (defined as 100% x (V MRglu - V SUV)/V SUV, where V is volume) ranged from -12.8% to -84.8%, with a median of -32.8%. CONCLUSION: Tumor volumes from MRglu maps were significantly smaller than SUV-based volumes. These findings can be of importance for PET-based radiotherapy planning and therapy response monitoring.