Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a highly transmissible and pathogenic coronavirus that emerged in late 2019 and has caused a pandemic of acute respiratory disease, named ‘coronavirus disease 2019’ (COVID-19), which threatens human health and public safety. In this Review, we describe the basic virology of SARS-CoV-2, including genomic characteristics and receptor use, highlighting its key difference from previously known coronaviruses. We summarize current knowledge of clinical, epidemiological and pathological features of COVID-19, as well as recent progress in animal models and antiviral treatment approaches for SARS-CoV-2 infection. We also discuss the potential wildlife hosts and zoonotic origin of this emerging virus in detail. In this Review, Shi and colleagues summarize the exceptional amount of research that has characterized acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and coronavirus disease 2019 (COVID-19) since this virus has swept around the globe. They discuss what we know so far about the emergence and virology of SARS-CoV-2 and the pathogenesis and treatment of COVID-19.

/pdf/characteristics-of-sars-cov-2-and-covid-19-eeqnaghpho.pdf

Characteristics of SARS-CoV-2 and COVID-19

The emergence of Middle East respiratory syndrome coronavirus (MERS-CoV) in 2012 marked the second introduction of a highly pathogenic coronavirus into the human population in the twenty-first century. The continuing introductions of MERS-CoV from dromedary camels, the subsequent travel-related viral spread, the unprecedented nosocomial outbreaks and the high case-fatality rates highlight the need for prophylactic and therapeutic measures. Scientific advancements since the 2002-2003 severe acute respiratory syndrome coronavirus (SARS-CoV) pandemic allowed for rapid progress in our understanding of the epidemiology and pathogenesis of MERS-CoV and the development of therapeutics. In this Review, we detail our present understanding of the transmission and pathogenesis of SARS-CoV and MERS-CoV, and discuss the current state of development of measures to combat emerging coronaviruses.

/pdf/sars-and-mers-recent-insights-into-emerging-coronaviruses-2ajbk9guw3.pdf

SARS and MERS: recent insights into emerging coronaviruses

The use of artificial intelligence, and the deep-learning subtype in particular, has been enabled by the use of labeled big data, along with markedly enhanced computing power and cloud storage, across all sectors. In medicine, this is beginning to have an impact at three levels: for clinicians, predominantly via rapid, accurate image interpretation; for health systems, by improving workflow and the potential for reducing medical errors; and for patients, by enabling them to process their own data to promote health. The current limitations, including bias, privacy and security, and lack of transparency, along with the future directions of these applications will be discussed in this article. Over time, marked improvements in accuracy, productivity, and workflow will likely be actualized, but whether that will be used to improve the patient-doctor relationship or facilitate its erosion remains to be seen.

High-performance medicine: the convergence of human and artificial intelligence

Over the last 10–15 years, our understanding of the composition and functions of the human gut microbiota has increased exponentially. To a large extent, this has been due to new ‘omic’ technologies that have facilitated large-scale analysis of the genetic and metabolic profile of this microbial community, revealing it to be comparable in influence to a new organ in the body and offering the possibility of a new route for therapeutic intervention. Moreover, it might be more accurate to think of it like an immune system: a collection of cells that work in unison with the host and that can promote health but sometimes initiate disease. This review gives an update on the current knowledge in the area of gut disorders, in particular metabolic syndrome and obesity-related disease, liver disease, IBD and colorectal cancer. The potential of manipulating the gut microbiota in these disorders is assessed, with an examination of the latest and most relevant evidence relating to antibiotics, probiotics, prebiotics, polyphenols and faecal microbiota transplantation.

/pdf/the-gut-microbiota-and-host-health-a-new-clinical-frontier-4pp0uoa4kb.pdf

The gut microbiota and host health: a new clinical frontier

Most older individuals develop inflammageing, a condition characterized by elevated levels of blood inflammatory markers that carries high susceptibility to chronic morbidity, disability, frailty, and premature death. Potential mechanisms of inflammageing include genetic susceptibility, central obesity, increased gut permeability, changes to microbiota composition, cellular senescence, NLRP3 inflammasome activation, oxidative stress caused by dysfunctional mitochondria, immune cell dysregulation, and chronic infections. Inflammageing is a risk factor for cardiovascular diseases (CVDs), and clinical trials suggest that this association is causal. Inflammageing is also a risk factor for chronic kidney disease, diabetes mellitus, cancer, depression, dementia, and sarcopenia, but whether modulating inflammation beneficially affects the clinical course of non-CVD health problems is controversial. This uncertainty is an important issue to address because older patients with CVD are often affected by multimorbidity and frailty — which affect clinical manifestations, prognosis, and response to treatment — and are associated with inflammation by mechanisms similar to those in CVD. The hypothesis that inflammation affects CVD, multimorbidity, and frailty by inhibiting growth factors, increasing catabolism, and interfering with homeostatic signalling is supported by mechanistic studies but requires confirmation in humans. Whether early modulation of inflammageing prevents or delays the onset of cardiovascular frailty should be tested in clinical trials. Inflammageing is a chronic, pro-inflammatory state that develops with age and is a risk factor for cardiovascular disease, comorbidities, frailty, and death. In this Review, Ferrucci and Fabbri discuss whether therapies to modulate inflammageing can reduce the age-related decline in health.

Inflammageing: chronic inflammation in ageing, cardiovascular disease, and frailty

Retrospective study: The diagnostic accuracy of conventional forceps biopsy of gastric epithelial compared to endoscopic submucosal dissection (STROBE compliant).

CONCLUSION:Probiotic therapies can reduce liver aminotransferases, total-cholesterol, TNF-α and improve insulin resistance in NAFLD patients. Modulation of the gut microbiota represents a new treatment for NAFLD.

Effects of probiotics on nonalcoholic fatty liver disease: A meta-analysis

AIM: To investigate the clinical pathologic features of gastrointestinal leiomyoma and the diagnostic value of endoscopic ultrasonography (EUS) on gastrointestinal leiomyoma.

METHODS: A total of 106 patients with gastrointestinal leiomyoma diagnosed with EUS were studied. The location, size and layer origin of gastric and esophageal leiomyomas were analyzed and compared. The histological diagnosis of the resected specimens by endoscopy or surgery in some patients was compared with their results of EUS.

RESULTS: The majority of esophageal leiomyomas were located in the middle and lower part of the esophagus and their size was smaller than 1.0 cm, and 62.1% of esophageal leiomyomas originated from the muscularis mucosae. Most of the gastric leiomyomas were located in the body and fundus of the stomach with a size of 1-2 cm. Almost all gastric leiomyomas (94.2%) originated from the muscularis propria. The postoperative histological results of 54 patients treated by endoscopic resection or surgical excision were completely consistent with the preoperative diagnosis of EUS, and the diagnostic specificity of EUS to gastrointestinal leiomyoma was 94.7%.

CONCLUSION: The size and layer origin of esophageal leiomyomas are different from that of gastric leiomyomas. Being safe and accurate, EUS is the best method not only for gastrointestinal leiomyoma diagnosis but also for the follow-up of patients.

Diagnostic value of endoscopic ultrasonography for gastrointestinal leiomyoma.

Background: Vitamin D receptor (VDR) is a member of the nuclear receptor family of transcription factors that play a critical role in innate immunity. This study examined the role of VDR in gastric innate immune defence against the gastric pathogen Helicobacter pylori. Materials and Methods: Seventeen H. pylori-infected patients and sixteen controls participated in the study. The GES-1 cells were transfected with siRNA or incubated with or without 1a,25(OH)2D3 (100 nmol/L) then infected with H. pylori. VDR, cathelicidin antimicrobial protein (CAMP), and cytokine mRNA expression levels in normal and H. pylori-infected gastric mucosa and GES-1 cells was determined by qRT-PCR and correlated with the histopathologic degree of gastritis. Bactericidal activity was measured by using a colony-forming unit assay. Results: Vitamin D receptor mRNA expression levels were significantly upregulated in H. pylori-infected patients and positively correlated with chronic inflammation scores. There was a significant positive correlation between VDR and CAMP mRNA expression in H. pylori-positive gastric mucosa. VDR siRNA reduced H. pylori-induced CAMP production and conversely increased IL-6 and IL8/CXCL8 expression levels. The vitamin D agonist 1a,25(OH)2D3 increased CAMP expression and reduced cytokine activation in GES-1 cells infected with H. pylori .1 a,25(OH)2D3 could enhance the intracellular killing of the replicating bacteria, but the presence of siVDR and siCAMP led to a decline in its bactericidal ability. Conclusions: The expression of VDR and CAMP in the gastric epithelium is up-regulated in the case of H. pylori infection; thus, VDR plays an important role in gastric mucosa homeostasis and host protection from H. pylori infection.

Helicobacter pylori Induces Increased Expression of the Vitamin D Receptor in Immune Responses

AIM: To analyze the clinical characteristics of small bowel tumors detected by double-balloon enteroscopy (DBE) and to evaluate the diagnostic value of DBE in tumors.

METHODS: Four hundred and forty consecutive DBE examinations were performed in 400 patients (250 males and 150 females, mean age 46.9 ± 16.3 years, range 14-86 years) between January 2007 and April 2012. Of these, 252 patients underwent the antegrade approach, and 188 patients underwent the retrograde approach. All the patients enrolled in our study were suspected of having small bowel diseases with a negative etiological diagnosis following other routine examinations, such as upper and lower gastrointestinal endoscopy and radiography tests. Data on tumors, such as clinical information, endoscopic findings and operation results, were retrospectively collected.

RESULTS: Small bowel tumors were diagnosed in 78 patients, of whom 67 were diagnosed using DBE, resulting in a diagnostic yield of 16.8% (67/400); the other 11 patients had negative DBE findings and were diagnosed through surgery or capsule endoscopy. Adenocarcinoma (29.5%, 23/78), gastrointestinal stromal tumor (24.4%, 19/78) and lymphoma (15.4%, 12/78) were the most common tumors. Among the 78 tumors, 60.3% (47/78) were located in the jejunum, and the overall number of malignant tumors was 74.4% (58/78). DBE examinations were frequently performed in patients with obscure gastrointestinal bleeding (47.4%) and abdominal pain (24.4%). The positive detection rate for DBE in the 78 patients with small bowel tumors was 85.9% (67/78), which was higher than that of a computed tomography scan (72.9%, 51/70). Based on the operation results, the accuracy rates of DBE for locating small bowel neoplasms, such as adenocarcinoma, gastrointestinal stromal tumor and lymphoma, were 94.4%, 100% and 100%, respectively. The positive biopsy rates for adenocarcinoma and lymphoma were 71.4% and 60%, respectively.

CONCLUSION: DBE is a useful diagnostic tool with high clinical practice value and should be considered the gold standard for the investigation of small bowel tumors.

Lihua Chen

Papers

Retrospective study: The diagnostic accuracy of conventional forceps biopsy of gastric epithelial compared to endoscopic submucosal dissection (STROBE compliant).

Effects of probiotics on nonalcoholic fatty liver disease: A meta-analysis

Diagnostic value of endoscopic ultrasonography for gastrointestinal leiomyoma.

Helicobacter pylori Induces Increased Expression of the Vitamin D Receptor in Immune Responses

Double-balloon enteroscopy in small bowel tumors: A Chinese single-center study