Performance evaluation of a novel 14C-urea breath test (solid scintillation) for the diagnosis of helicobacter pylori infection.

14C-urea breath tests (UBTs) can be used to diagnose helicobacter pylori (H. pylori) infection. This study aimed to evaluate the accuracy of a solid scintillation 14C-UBT in diagnosing H pylori infection. This open-label, prospective multicenter study enrolled patients who underwent H pylori screening from January 7, 2020, to October 28, 2020, in 3 centers in China. All participants underwent solid scintillation UBT first and then gastroscopy. The rapid urease test and histological examination results were the gold standards (H pylori-positive was defined as the 2 tests being positive; H pylori-negative was defined as both tests being negative). The solid scintillation 14C-UBT involves a scintillation sampling bottle and a 14C-urea capsule. The sampling bottle contains a stack of carbon dioxide-absorbing and scintillation sheets. The test is read using a photomultiplier. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value for H pylori infection were evaluated. This study enrolled 239 participants. There were 98 males and 141 females, aged 45.8 ±â€…11.9 (range: 21-66) years. Thirty-four participants were excluded due to a discrepancy between the rapid urease test and immunohistochemistry examination. Finally, 205 participants were included in the analysis. According to the gold standard, 87 out of 205 (42.4%) participants were H pylori-positive. Compared with the gold standard, the sensitivity, specificity, accuracy, and positive and negative predictive values of the solid scintillation 14C-UBT were 95.4%, 97.5%, 96.6%, 96.5%, and 96.6% for the solid scintillation UBT, respectively. One participant experienced 1 adverse event (AE) (exacerbation of chronic cholecystitis), and the AE eventually improved by itself. The investigators determined that the AE was unrelated to the study device. The noninvasive solid scintillation 14C-UBT has a high diagnostic value for H pylori infection, comparable to the diagnostic value of the gold standard.

DEFAEK: Domain Effective Fast Adaptive Network for Face Anti-Spoofing.

Existing deep learning based face anti-spoofing (FAS) or deepfake detection approaches usually rely on large-scale datasets and powerful networks with significant amount of parameters to achieve satisfactory performance. However, these make them resource-heavy and unsuitable for handheld devices. Moreover, they are limited by the types of spoof in the dataset they train on and require considerable training time. To produce a robust FAS model, they need large datasets covering the widest variety of predefined presentation attacks possible. Testing on new or unseen attacks or environments generally results in poor performance. Ideally, the FAS model should learn discriminative features that can generalize well even on unseen spoof types. In this paper, we propose a fast learning approach called Domain Effective Fast Adaptive nEt-worK (DEFAEK), a face anti-spoofing approach based on the optimization-based meta-learning paradigm that effectively and quickly adapts to new tasks. DEFAEK treats differences in an environment as domains and simulates multiple domain shifts during training. To further improve the effectiveness and efficiency of meta-learning, we adopt the metric learning in the inner loop update with careful sample selection. With extensive experiments on the challenging CelebA-Spoof and FaceForensics++ datasets, the evaluation results show that DEFAEK can learn cues independent of the environment with good generalization capability. In addition, the resulting model is lightweight following the design principle of modern lightweight network architecture and still generalizes well on unseen classes. In addition, we also demonstrate our model's capabilities by comparing the numbers of parameters, FLOPS, and model performance with other state-of-the-art methods.

AK048794 maintains the mouse embryonic stem cell pluripotency by functioning as an miRNA sponge for miR-592.

MiR-592 has been identified as a neural-enriched microRNA, plays an important role in mNPCs differentiation, could induce astrogliogenesis differentiation arrest or/and enhance neurogenesis in vitro Previous studies showed that long noncoding RNAs (lncRNAs) were involved in the neuronal development and activity. To investigate the role of miR-592 in neurogenesis, we described the expression profile of lncRNAs in miR-592 knockout mouse embryonic stem cells (mESCs) and the corresponding normal mESCs by microarray. By the microarray analysis and luciferase reporter assays, we demonstrated that lncRNA - AK048794, regulated by transcription factor GATA1, functioned as a competing endogenous RNA (ceRNA) for miR-592 and led to the de-repression of its endogenous target FAM91A1, which is involved in mESC pluripotency maintenance. Taken together, these observations imply that AK048794 modulated the expression of multiple genes involved in mESC pluripotency maintenance by acting as a ceRNA for miR-592, which may build up the link between the regulatory miRNA network and mESC pluripotency.

Acute pancreatitis associated with herpes zoster: case report and literature review.

Varicella-zoster virus (VZV) is a type of herpes virus known to cause varicella, mainly in young children, and herpes zoster in adults. Although generally non-lethal, VZV infection can be associated with serious complications, particularly in adults. Acute pancreatitis caused by VZV infection is a rare event, with reports primarily concerning immunocompromised individuals. Here we report a 44-year-old immunocompetent female who developed acute pancreatitis associated with VZV infection. The patient presented with vomiting and persistent pain in the upper quadrant less than one week after diagnosis and treatment for a herpes zoster-related rash with stabbing pain on the abdomen and dorsal right trunk side. A diagnosis of acute pancreatitis was confirmed based on abdominal pain, elevated levels of urine and serum amylase, and findings of peri-pancreatic exudation and effusions by computed tomography and magnetic resonance cholangiopancreatography. This case highlights that, though rare, acute pancreatitis should be considered in VZV patients who complain of abdominal pain, especially in the epigastric area. Early detection and proper treatment are needed to prevent the condition from deteriorating further and to minimize mortality.

Gene expression profile of Helicobacter pylori in response to growth temperature variation.

A Helicobacter pylori whole-genome DNA microarray was constructed to study expression profiles of H. pylori in response to a sudden temperature transfer from 37 degrees C to 20 degrees C. The expression level of the genome at each of four time points (15, 30, 60, and 120 min) after temperature downshift was compared with that just before cold treatment. Globally, 10.2 % (n=167) of the total predicted H. pylori genes (n=1636) represented on the microarray were significantly differentially expressed (p<0.05) over a 120 min period after shift to low temperature. The expression profiles of the differentially expressed genes were grouped, and their expression patterns were validated by quantitative real-time PCR. Up-regulated genes mainly included genes involved in energy metabolism and substance metabolism, cellular processes, protein fate, ribosomal protein genes, and hypothetical protein genes, which indicate the compensational responses of H. pylori to temperature downshift. Those genes play important roles in adaption to temperature downshift of H. pylori. Down-regulation of DNA metabolism genes and cell envelope genes and cellular processes genes may reflect damaged functions under low temperature, which is unfavorable to bacterial infection and propagation. Overall, this time-course study provides new insights into the primary response of H. pylori to a sudden temperature downshift, which allow the bacteria to survive and adapt to the new host environment.

Comparative genomics profiling of clinical isolates of Helicobacter pylori in Chinese populations using DNA microarray.

In order to search for specific genotypes related to this unique phenotype, we used whole genomic DNA microarray to characterize the genomic diversity of Helicobacter pylori (H. pylori) strains isolated from clinical patients in China. The open reading frame (ORF) fragments on our microarray were generated by PCR using gene-specific primers. Genomic DNA of H. pylori 26695 and J99 were used as templates. Thirty-four H. pylori isolates were obtained from patients in Shanghai. Results were judged based on ln(x) transformed and normalized Cy3/Cy5 ratios. Our microarray included 1882 DNA fragments corresponding to 1636 ORFs of both sequenced H. pylori strains. Cluster analysis, revealed two diverse regions in the H. pylori genome that were not present in other isolates. Among the 1636 genes, 1091 (66.7%) were common to all H. pylori strains, representing the functional core of the genome. Most of the genes found in the H. pylori functional core were responsible for metabolism, cellular processes, transcription and biosynthesis of amino acids, functions that are essential to H. pylori's growth and colonization in its host. In contrast, 522 (31.9%) genes were strain-specific genes that were missing from at least one strain of H. pylori. Strain-specific genes primarily included restriction modification system components, transposase genes, hypothetical proteins and outer membrane proteins. These strain-specific genes may aid the bacteria under specific circumstances during their long-term infection in genetically diverse hosts. Our results suggest 34 H. pylori clinical strains have extensive genomic diversity. Core genes and strain-specific genes both play essential roles in H. pylori propagation and pathogenesis. Our microarray experiment may help select relatively significant genes for further research on the pathogenicity of H. pylori and development of a vaccine for H. pylori.

Clinical relevance of iceA and babA2 genotypes of Helicobacter pylori in a Shanghai population.

OBJECTIVE: To determine the distribution of the iceA and babA2 genotypes of Helicobacter pylori in patients with various gastroduodenal diseases in Shanghai, and to explore the association between genotype and the clinical outcome of infection. METHODS: One hundred and forty-one strains of H. pylori were isolated from gastric biopsies of 43 patients with chronic gastritis, 47 with duodenal ulcer (DU), 30 with gastric ulcer (GU) and 21 with non-cardia gastric carcinoma. The iceA, babA2, cagA and vacA genotypes were determined by polymerase chain reaction (PCR). RESULTS: The iceA1, iceA2 and babA2 genotypes were detected in 74.5% (105/141), 15.6% (22/141) and 63.8% (90/141), respectively, of the H. pylori strains studied. Two H. pylori isolates (1.4%) were positive for both iceA alleles and 16 (11.3%) were negative for both. The prevalence of babA2 and its combination with cagA (cagA(+)/babA2(+)) in DU patients was significantly higher than that in GU patients (74.5%vs 50.0% for babA2, P = 0.028; 70.2%vs 46.7% for cagA(+)/babA2(+), P = 0.039). There was no significant difference in the prevalence of babA2 among the other disease groups, and no significant association of the iceA genotypes with the different clinical diseases (P > 0.05). CONCLUSIONS: The most predominant genotype of the H. pylori strains isolated from patients in Shanghai are iceA1(+)/babA2(+), and the babA2 genotype may play a different role in the pathogenesis of DU and GU. An association between iceA status and clinical outcome of H. pylori infection could not be confirmed in the present study.