Acute Gastrointestinal Bleeding in COVID-19 Patients: A Systematic Review and Meta-Analysis

Background/Aims More than 100 million people to date have been affected by the coronavirus disease-2019 (COVID-19) pandemic. Patients with COVID-19 have a higher risk of bleeding complications. We performed a systematic review and meta-analysis to evaluate the outcomes of COVID-19 patients with signs and symptoms of acute gastrointestinal bleeding (GIB). Methods A systematic literature search was carried out for articles published until until November 11, 2020, in the Embase, MEDLINE, Web of Science, and Cochrane Library databases. We included studies on COVID-19 patients with signs and symptoms of GIB. Results Our search yielded 49 studies, of which eight with a collective 127 patients (86 males and 41 females) met our inclusion criteria. Conservative management alone was performed in 59% of the patients, endoscopic evaluation in 31.5%, and interventional radiology (IR) embolization in 11%. Peptic ulcer disease was the most common endoscopic finding, diagnosed in 47.5% of the patients. Pooled overall mortality was 19.1% (95% confidence interval [CI]; 12.7%-27.6%) and pooled mortality secondary to GIB was 3.5% (95% CI; 1.3%–9.1%). The pooled risk of rebleeding was 11.3% (95% CI; 6.8%–18.4%). Conclusions The majority of COVID-19 patients with GIB responded to conservative management, with a low mortality rate associated with GIB and the risk of rebleeding. Thus, we suggest limiting endoscopic and IR interventions to those with hemodynamic instability and those for whom conservative management was unsuccessful

Production of Plant Secondary Metabolites: Examples, Tips and Suggestions for Biotechnologists

Plants are sessile organisms and, in order to defend themselves against exogenous (a)biotic constraints, they synthesize an array of secondary metabolites which have important physiological and ecological effects. Plant secondary metabolites can be classified into four major classes: terpenoids, phenolic compounds, alkaloids and sulphur-containing compounds. These phytochemicals can be antimicrobial, act as attractants/repellents, or as deterrents against herbivores. The synthesis of such a rich variety of phytochemicals is also observed in undifferentiated plant cells under laboratory conditions and can be further induced with elicitors or by feeding precursors. In this review, we discuss the recent literature on the production of representatives of three plant secondary metabolite classes: artemisinin (a sesquiterpene), lignans (phenolic compounds) and caffeine (an alkaloid). Their respective production in well-known plants, i.e., Artemisia, Coffea arabica L., as well as neglected species, like the fibre-producing plant Urtica dioica L., will be surveyed. The production of artemisinin and caffeine in heterologous hosts will also be discussed. Additionally, metabolic engineering strategies to increase the bioactivity and stability of plant secondary metabolites will be surveyed, by focusing on glycosyltransferases (GTs). We end our review by proposing strategies to enhance the production of plant secondary metabolites in cell cultures by inducing cell wall modifications with chemicals/drugs, or with altered concentrations of the micronutrient boron and the quasi-essential element silicon

Full-length human placental sFlt-1-e15a isoform induces distinct maternal phenotypes of preeclampsia in mice

<div><p>Objective</p><p>Most anti-angiogenic preeclampsia models in rodents utilized the overexpression of a truncated soluble fms-like tyrosine kinase-1 (sFlt-1) not expressed in any species. Other limitations of mouse preeclampsia models included stressful blood pressure measurements and the lack of postpartum monitoring. We aimed to 1) develop a mouse model of preeclampsia by administering the most abundant human placental sFlt-1 isoform (hsFlt-1-e15a) in preeclampsia; 2) determine blood pressures in non-stressed conditions; and 3) develop a survival surgery that enables the collection of fetuses and placentas and postpartum (PP) monitoring.</p><p>Methods</p><p>Pregnancy status of CD-1 mice was evaluated with high-frequency ultrasound on gestational days (GD) 6 and 7. Telemetry catheters were implanted in the carotid artery on GD7, and their positions were verified by ultrasound on GD13. Mice were injected through tail-vein with adenoviruses expressing hsFlt-1-e15a (n = 11) or green fluorescent protein (GFP; n = 9) on GD8/GD11. Placentas and pups were delivered by cesarean section on GD18 allowing PP monitoring. Urine samples were collected with cystocentesis on GD6/GD7, GD13, GD18, and PPD8, and albumin/creatinine ratios were determined. GFP and hsFlt-1-e15a expression profiles were determined by qRT-PCR. Aortic ring assays were performed to assess the effect of hsFlt-1-e15a on endothelia.</p><p>Results</p><p>Ultrasound predicted pregnancy on GD7 in 97% of cases. Cesarean section survival rate was 100%. Mean arterial blood pressure was higher in hsFlt-1-e15a-treated than in GFP-treated mice (∆MAP = 13.2 mmHg, p = 0.00107; GD18). Focal glomerular changes were found in hsFlt-1-e15a -treated mice, which had higher urine albumin/creatinine ratios than controls (109.3±51.7μg/mg vs. 19.3±5.6μg/mg, p = 4.4x10^-2; GD18). Aortic ring assays showed a 46% lesser microvessel outgrowth in hsFlt-1-e15a-treated than in GFP-treated mice (p = 1.2x10^-2). Placental and fetal weights did not differ between the groups. One mouse with liver disease developed early-onset preeclampsia-like symptoms with intrauterine growth restriction (IUGR).</p><p>Conclusions</p><p>A mouse model of late-onset preeclampsia was developed with the overexpression of hsFlt-1-e15a, verifying the <i>in vivo</i> pathologic effects of this primate-specific, predominant placental sFlt-1 isoform. HsFlt-1-e15a induced early-onset preeclampsia-like symptoms associated with IUGR in a mouse with a liver disease. Our findings support that hsFlt-1-e15a is central to the terminal pathway of preeclampsia, and it can induce the full spectrum of symptoms in this obstetrical syndrome.</p></div

Prevalence and pattern of misconceptions about semen loss and sexual prowess among male medical interns

Introduction: Sexual misconceptions have been around in India for a very long time. Growing liberal attitudes toward sex and sexual permissiveness can be expected to occur in the context of improved sexual knowledge among people. However, sexual myths continue to remain rampant. Therefore, the present study was planned with the aim to assess the level of sexual misconceptions regarding semen loss prevalent among male medical interns. Participants and Methods: This was a cross-sectional study among unmarried male medical students doing an internship. Eighty-one interns were recruited after fulfilling predecided inclusion/exclusion criteria and were asked to complete a specially made questionnaire to assess their sexual beliefs anonymously in complete privacy. Responses were analyzed using frequency distribution. Results: Seventy-nine percent of the participants believed that loss of semen can lead to reduction in the size of the penis, while 44.44% (n = 36) believed that it leads to sexual weakness, 56.8% (n = 46) believed it can lead to physical weakness, and 56.8% (n = 46) believed that excess masturbation can decrease sexual prowess. Discussion: This study helps bring to light the prevalence of sexual misconceptions among medical interns in spite of reaching a stage where they are expected to have sound conceptual, theoretical, and practical knowledge about sexual health and wellbeing. There is a dearth of national and international studies exploring the sociocultural aspects of sexuality specifically among medical students. The findings from this study are expected to stimulate researchers and academicians into further exploring the aspect of sexuality among the young medical fraternity

FULL PAPER Magnetic Resonance in Medicine 000:000–000 (2012) Feasibility of Shutter-Speed DCE-MRI for Improved Prostate Cancer Detection

The feasibility of shutter-speed model dynamic-contrastenhanced MRI pharmacokinetic analyses for prostate cancer detection was investigated in a prebiopsy patient cohort. Differences of results from the fast-exchange-regime-allowed (FXR-a) shutter-speed model version and the fast-exchangelimit-constrained (FXL-c) standard model are demonstrated. Although the spatial information is more limited, postdynamic-contrast-enhanced MRI biopsy specimens were also examined. The MRI results were correlated with the biopsy pathology findings. Of all the model parameters, region-of-interest-averaged K trans difference [DK trans: K trans (FXR-a) 2 K trans (FXL-c)] or two-dimensional K trans (FXR-a) vs. k ep(FXR-a) values were found to provide the most useful biomarkers for malignant/benign prostate tissue discrimination (at 100 % sensitivity for a population of 13, the specificity is 88%) and diseas