Essential Role of Non-Conserved α4-His178 in Stabilizing the α4-α5 Hairpin and Biotoxicity of the Cry4Aa Mosquitocidal Protein.

Background: Bacillus thuringiensis Cry toxins are well known for their insecticidal properties, primarily through the formation of ion-leakage pores via α4-α5 hairpins. His178 in helix 4 of the Cry4Aa mosquito-active toxin has been suggested to play a crucial role in its biotoxicity.

Objective: This study aimed to investigate the functional importance of Cry4Aa-His178 through experimental and computational analyses.

Enhancing recombinant antibody yield in Chinese hamster ovary cells.

A range of recombinant monoclonal antibodies (rMAbs) have found application in treating diverse diseases, spanning various cancers and immune system disorders. Chinese hamster ovary (CHO) cells have emerged as the predominant choice for producing these rMAbs due to their robustness, ease of transfection, and capacity for posttranslational modifications akin to those in human cells. Transient transfection and/or stable expression could be conducted to express rMAbs in CHO cells.

Hepatitis C Virus Down-Regulates the Expression of Ribonucleotide Reductases to Promote Its Replication.

Ribonucleotide reductases (RRs or RNRs) catalyze the reduction of the OH group on the 2nd carbon of ribose, reducing four ribonucleotides (NTPs) to the corresponding deoxyribonucleotides (dNTPs) to promote DNA synthesis. Large DNA viruses, such as herpesviruses and poxviruses, could benefit their replication through increasing dNTPs via expression of viral RRs. Little is known regarding the relationship between cellular RRs and RNA viruses.

Optimized high-yield preparation of alkaline-solubilizable crystalline inclusion of the Bacillus thuringiensis Cry4Aa δ-endotoxin expressed in Escherichia coli.

The native Cry4Aa δ-endotoxin produced exclusively in Bacillus thuringiensis during sporulation as a ∼130-kDa inactive protoxin is confined within the parasporal crystalline inclusion that dissolves at alkaline pH in the midgut lumen of mosquito larvae. Here, the recombinant Cry4Aa toxin over-expressed in Escherichia coli at 30 °C as an alkaline-solubilizable inclusion was found inevitably lost during isolation from the cell lysate (pH ∼6.5) of which host cells were pre-suspended in distilled water (pH ∼5.

Conserved loop residues-Tyr and Asn near the catalytic site of the lysostaphin endopeptidase are essential for staphylolytic activity toward pentaglycine binding and catalysis.

Lysostaphin endopeptidase cleaves pentaglycine cross-bridges found in staphylococcal cell-wall peptidoglycans and proves very effective in combatting methicillin-resistant Staphylococcus aureus. Here, we revealed the functional importance of two loop residues, Tyr in loop 1 and Asn in loop 4, which are highly conserved among the M23 endopeptidase family and are found close to the Zn-coordinating active site. Detailed analyses of the binding groove architecture together with protein-ligand docking showed that these two loop residues potentially interact with the docked ligand-pentaglycine.

Salmonella typhimurium exacerbates injuries but resolves fibrosis in liver and spleen during Schistosoma mansoni infection.

Background: In most developing or undeveloped countries, patients are often co-infected with multiple pathogens rather than a single pathogen. While different pathogens have their impact on morbidity and mortality, co-infection of more than one pathogen usually made the disease outcome different. Many studies reported the co-infection of Schistosoma with Salmonella in pandemic areas.

Strategies of Influenza A Virus to Ensure the Translation of Viral mRNAs.

Viruses are obligatorily intracellular pathogens. To generate progeny virus particles, influenza A viruses (IAVs) have to divert the cellular machinery to ensure sufficient translation of viral mRNAs. To this end, several strategies have been exploited by IAVs, such as host gene shutoff, suppression of host innate immune responses, and selective translation of viral mRNAs.

Cellular PSMB4 Protein Suppresses Influenza A Virus Replication through Targeting NS1 Protein.

The nonstructural protein 1 (NS1) of influenza A virus (IAV) possesses multiple functions, such as the inhibition of the host antiviral immune responses, to facilitate viral infection. To search for cellular proteins interacting with the IAV NS1 protein, the yeast two-hybrid system was adopted. Proteasome family member PSMB4 (proteasome subunit beta type 4) was found to interact with the NS1 protein in this screening experiment.

Cry4Aa and Cry4Ba Mosquito-Active Toxins Utilize Different Domains in Binding to a Particular ALP Isoform: A Functional Toxin Receptor Implicating Differential Actions on Target Larvae.

The three-domain Cry4Aa toxin produced from subsp. was previously shown to be much more toxic to mosquito larvae than its closely related toxin-Cry4Ba. The interaction of these two individual toxins with target receptors on susceptible larval midgut cells is likely to be the critical determinant in their differential toxicity.

Roles of microRNAs in Hepatitis C Virus Replication and Pathogenesis.

Hepatitis C virus (HCV) infection is associated with the development of chronic liver diseases, e.g., fibrosis, cirrhosis, even hepatocellular carcinoma, and/or extra-hepatic diseases such as diabetes.

Long noncoding RNAs in hepatitis B virus replication and oncogenesis.

Several diverse long noncoding RNAs (lncRNAs) have been identified to be involved in hepatitis B virus (HBV) replication and oncogenesis, especially those dysregulated in HBV-related hepatocellular carcinoma (HCC). Most of these dysregulated lncRNAs are modulated by the HBV X protein. The regulatory mechanisms of some lncRNAs in HBV replication and oncogenesis have been characterized.

Complete structure elucidation of a functional form of the Bacillus thuringiensis Cry4Ba δ-endotoxin: Insights into toxin-induced transmembrane pore architecture.

The insecticidal nature of Cry δ-endotoxins produced by Bacillus thuringiensis is generally attributed to their ability to form transmembrane pores, causing lysis of target insect cells. Previously, the truncated tertiary structure of the chymotrypsin-treated Cry4Ba toxin lacking the N-terminal helices-α1 and α2 was reported. To elucidate a more complete functional structure, a 65-kDa trypsin-activated form of the Cry4Ba-R203Q mutant toxin was thus generated for X-ray crystallography by eliminating the Arg-tryptic cleavage site.

Prevalence, clinical features and prescription patterns of psychotropic medications for patients with psychotic depression in China.

Objective: To investigate the prevalence of psychotic depression and the differences in sociodemographic and clinical characteristics and prescription patterns of psychotropic medications between patients with psychotic depression (PD) and patients with nonpsychotic depression (NPD) in China.

Methods: We conducted a cross-sectional study in 13 major psychiatric hospitals or the psychiatric units of general hospitals in China from September 1, 2010, to February 28, 2011. PD was defined according to the psychotic disorder section of the Mini International Neuropsychiatric Interview (MINI).

Family Physicians Working at Hospitals: A 20-Year Nationwide Trend Analysis in Taiwan.

Family physicians play an essential role as gatekeepers in primary health care. However, most studies in the past focused on the geographic maldistribution of family physicians, and few studies focused on the distribution of family physicians between private practices and hospitals. This study aims to analyze the trends in practice locations of family physicians in Taiwan between 1999 and 2018, using the databases of the Taiwan Association of Family Medicine and Taiwan Medical Association.

Cry4Ba Insecticidal ToxinExploits Leu in Its C-Terminal Domain to Interact with a Target Receptor- Membrane-Bound Alkaline Phosphatase.

In addition to the receptor-binding domain (DII), the C-terminal domain (DIII) of three-domain Cry insecticidal δ-endotoxins from has been implicated in target insect specificity, yet its precise mechanistic role remains unclear. Here, the 21 kDa high-purity isolated DIII fragment derived from the Cry4Ba mosquito-specific toxin was achieved via optimized preparative FPLC, allowing direct rendering analyses for binding characteristics toward its target receptor- membrane-bound alkaline phosphatase (Aa-mALP). Binding analysis via dotblotting revealed that the Cry4Ba-DIII truncate was capable of specific binding to nitrocellulose-bound Aa-mALP, with a binding signal comparable to its 65 kDa Cry4Ba-R203Q full-length toxin.

Cellular factors involved in the hepatitis C virus life cycle.

The hepatitis C virus (HCV), an obligatory intracellular pathogen, highly depends on its host cells to propagate successfully. The HCV life cycle can be simply divided into several stages including viral entry, protein translation, RNA replication, viral assembly and release. Hundreds of cellular factors involved in the HCV life cycle have been identified over more than thirty years of research.

COVID-19 Publications in Family Medicine Journals in 2020: A PubMed-Based Bibliometric Analysis.

Family medicine physicians have been on the front lines of the novel coronavirus disease 2019 (COVID-19) pandemic; however, research and publications in family medicine journals are rarely discussed. In this study, a bibliometric analysis was conducted on COVID-19-related articles published in PubMed-indexed English language family medicine journals in 2020, which recorded the publication date and author's country and collected citations from Google Scholar. Additionally, we used LitCovid (an open database of COVID-19 literature from PubMed) to determine the content categories of each article and total number of global publications.

Antibodies Targeting Two Epitopes in SARS-CoV-2 Neutralize Pseudoviruses with the Spike Proteins from Different Variants.

The COVID-19 pandemic was caused by SARS-CoV-2 infection. To prevent the spread of SARS-CoV-2, an effective vaccine is required. Two linear peptides from potential B-cell epitopes in the spike protein of SARS-CoV-2 (a.

The role of patient records in research: A bibliometric analysis of publications from an academic medical center in Taiwan.

Background: This study aimed to assess the use of medical record items in clinical research in one large academic medical center in Taiwan.

Methods: A descriptive survey design was adopted to collect the data. Articles published in 2018 by Taipei Veterans General Hospital (TVGH) staff as the first author were obtained.

Differential Age Trajectories of White Matter Changes Between Sexes Correlate with Cognitive Performances.

Aging is accompanied by a gradual deterioration in multiple cognitive abilities and brain structures. Both cognitive function and white matter (WM) structure are found to be associated with neurodegeneration diseases and correlated with sex during aging. However, it is still unclear whether the brain structural change could be attributable to sex, and how sex would affect cognitive performances during aging.

Hepatitis C Viral Replication Complex.

The life cycle of the hepatitis C virus (HCV) can be divided into several stages, including viral entry, protein translation, RNA replication, viral assembly, and release. HCV genomic RNA replication occurs in the replication organelles (RO) and is tightly linked to ER membrane alterations containing replication complexes (proteins NS3 to NS5B). The amplification of HCV genomic RNA could be regulated by the RO biogenesis, the viral RNA structure (i.

His in the pore-lining α4 of the Bacillus thuringiensis Cry4Aa δ-endotoxin is crucial for structural arrangements of the α4-α5 transmembrane hairpin and hence biotoxicity.

One proposed toxic mechanism of Bacillus thuringiensis Cry δ-endotoxins involves pore formation in target membranes by the α4-α5 transmembrane hairpin constituting their pore-forming domain. Here, nine selected charged and uncharged polar residues in the pore-lining α4 of the Cry4Aa mosquito-active toxin were substituted with Ala. All mutant toxins, i.

N-Terminally Added Tag Selectively Enhances Heterologous Expression of VacA Cytotoxin Variants from Helicobacter pylori.

Background: Gastric pathogen Helicobacter pylori secretes VacA cytotoxin displaying a high degree of polymorphic variations of which the highest VacA pathogenicity correlates with m1-type variant followed by VacA-m2.

Objective: To comparatively evaluate expression in Escherichia coli of the mature VacA variants (m1- and m2-types) and their 33- and 55/59-kDa domains fused with His tag at N- or C-terminus.

Methods: All VacA clones expressed in E.