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Background: Helicobacter pylori infection induces cellular phenotypes relevant for cancer progression, namely cell motility and invasion. We hypothesized that the extracellular matrix (ECM) could be involved in these deleterious effects., Methods: Microarrays were used to uncover ECM interactors in cells infected with H. pylori. LAMC2, encoding laminin γ2, was selected as a candidate gene and its expression was assessed in vitro and in vivo. The role of LAMC2 was investigated by small interference RNA (siRNA) combined with a set of functional assays. Laminin γ2 and E-cadherin expression patterns were evaluated in gastric cancer cases., Results: Laminin γ2 was found significantly overexpressed in gastric cancer cells infected with H. pylori. This finding was validated in vitro by infection with clinical isolates and in vivo by using gastric biopsies of infected and noninfected individuals. We showed that laminin γ2 overexpression is dependent on the bacterial type IV secretion system and on the CagA. Functionally, laminin γ2 promotes cell invasion and resistance to apoptosis, through modulation of Src, JNK, and AKT activity. These effects were abrogated in cells with functional E-cadherin., Conclusions: These data highlight laminin γ2 and its downstream effectors as potential therapeutic targets, and the value of H. pylori eradication to delay gastric cancer onset and progression., Competing Interests: Potential conflicts of interest. All authors: No reported conflicts of interest. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed., (© The Author(s) 2022. Published by Oxford University Press on behalf of Infectious Diseases Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: Antimicrobial resistance (AMR) is one of the biggest threats to global public health. Selection of resistant bacteria is driven by inappropriate use of antibiotics, amongst other factors. COVID-19 may have exacerbated AMR due to unnecessary antibiotic prescribing. Country-level knowledge is needed to understand options for action., Objectives: To review the situation with respect to AMR in Brazil and initiatives addressing it. Identifying areas where more information is required will provide a call to action to minimize any further rises in AMR within Brazil and to improve patient outcomes., Methods: National initiatives to address AMR, antibiotic use and prescribing in Brazil, and availability of susceptibility data, particularly for the key community-acquired respiratory tract infections (CA-RTI) pathogens Streptococcus pneumoniae and Haemophilus influenzae, were identified. National and international antibiotic prescribing guidelines for CA-RTIs (community-acquired pneumonia, acute otitis media and acute bacterial rhinosinusitis) commonly used locally were also reviewed, along with local antibiotic availability., Conclusions: In Brazil there have been some initiatives addressing AMR such as the National Action Plan for AMR, established in 2018. Antibiotic consumption in Brazil is high but a ban on over-the-counter sales of antibiotics has led to a decrease in consumption. Local antibiotic susceptibility testing needs to be increased and the Survey of Antibiotic Resistance (SOAR) study in Brazil will provide useful data for pathogens causing CA-RTIs. A more standardized inclusive approach in developing local guidelines, using up-to-date surveillance data of isolates from community-acquired infections in Brazil, could make guideline use more locally relevant for clinicians. This would pave the way for a higher level of appropriate antibiotic prescribing and improved adherence. This would, in turn, potentially limit AMR development and improve clinical outcomes for patients., (© The Author(s) 2022. Published by Oxford University Press on behalf of British Society for Antimicrobial Chemotherapy.)

Background: Patients' objectives and experiences must be core to the study and management of chronic diseases, such as SSc. Although patient-reported outcomes are attracting increasing attention, evaluation of the impact of disease on the overall subjective well-being, equivalent to 'happiness', is remarkably lacking., Objectives: To examine the determinants of happiness and quality of life in patients with SSc, with emphasis on disease features and personality traits., Methods: Observational, cross-sectional multicentre study, including 142 patients, with complete data regarding disease activity, disease impact, personality, health-related quality of life (HR-QoL) and happiness. Structural equation modelling was used to evaluate the association between the variables., Results: The results indicated an acceptable fit of the model to the data. Perceived disease impact had a significant negative direct relation with HR-QoL (β = -0.79, P < 0.001) and with happiness (β = -0.52, P < 0.001). Positive personality traits had a positive relation with happiness (β = 0.36, P = 0.002) and an important indirect association upon QoL (β = 0.43) and happiness (β = 0.23). Perceived disease impact is influenced by body image, fatigue and SSc-related disability to a higher degree (β = 0.6-0.7) than by disease activity (β = 0.28) or form (β = 0.17). Impact of disease had a much stronger relation with HR-QoL than with happiness., Conclusions: The results suggest that treatment strategies targeting not only disease control but also the mitigation of relevant domains of disease impact (body image, fatigue, global disability) may be important to improve patients' experience of the disease. The reinforcement of resilience factors, such as positive psychological traits, may also play a contributory role towards better patient outcomes., (© The Author(s) 2021. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Helicobacter pylori colonizes the human stomach and increases the risk for peptic ulcer disease and gastric carcinoma. H. pylori upregulates the expression and activity of several matrix metalloproteinases (MMPs) in cell lines and in the gastric mucosa. The aim of this study was to explore the mechanisms leading to upregulation of MMP10 in gastric epithelial cells induced by H. pylori Infection of gastric cells with H. pylori led to an increase in levels of MMP-10 messenger RNA, protein secretion, and activity. cagA knockout mutants or CagA phosphorylation-defective mutants failed to increase MMP10 expression. These results were confirmed in infection experiments with clinical isolates with known cagA status and in human gastric biopsy specimens. Treatment of cells with chemical inhibitors of the receptor tyrosine kinase EGFR and the kinase Src abrogated H. pylori-induced MMP10 expression. Inhibitors of ERK1/2 and JNK kinases abolished and significantly decreased H. pylori-induced MMP10 expression, respectively, whereas inhibition of the kinase p38 had no effect. Finally, inhibition of MMP10 expression by small interfering RNA led to a decrease in the gastric cell-invasive phenotype mediated by the infection. In conclusion, CagA-positive H. pylori strains stimulate MMP10 expression. MMP-10 modulation occurs via EGFR activation in a process that involves Src, ERK, and JNK pathways. MMP-10 may be implicated in H. pylori-mediated extracellular matrix remodeling., (© The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.)

Oocyte quality is known to be a major cause of infertility in repeat-breeder (RB) and heat-stressed dairy cows. However, the mechanisms by which RB oocytes become less capable of supporting embryo development remain largely unknown. Thus, the aim of this study was to investigate whether the decreased oocyte competence of RB cows (RBs) during summer is associated with an altered gene expression profile and a decrease in mitochondrial DNA (mtDNA) copy number. Therefore, oocytes collected from heifers, non-RBs in peak lactation (PLs), and RBs were used to evaluate mtDNA amounts as well as the expression levels of genes associated with the mitochondria (MT-CO1, NRF1, POLG, POLG2, PPARGC1A, and TFAM), apoptosis (BAX, BCL2, and ITM2B), and oocyte maturation (BMP15, FGF8, FGF10, FGF16, FGF17, and GDF9). The oocytes retrieved from RBs during winter contained over eight times more mtDNA than those retrieved from RBs during summer. They also contained significantly less mtDNA than oocytes retrieved from heifers and PLs during summer. Moreover, the expression of mitochondria- (NRF1, POLG, POLG2, PPARGC1A, and TFAM) and apoptosis-related (BAX and ITM2B) genes, as well as of GDF9, in RB oocytes collected during summer was significantly greater than that in oocytes collected from heifers and PLs during the same season. In oocytes from heifers and PLs, the expression levels of these genes were lower in those collected during summer compared with winter, but this difference was not observed in oocytes collected from RBs. Altogether, these data provide evidence of altered gene expression and reduced mtDNA copy number in the oocytes collected from RBs during summer. This indicates a loss of fertility in RBs during summer, which might be caused by a possible mitochondrial dysfunction associated with a greater chance of oocytes to undergo apoptosis., (© 2016 by the Society for the Study of Reproduction, Inc.)

Heterogeneity at the Helicobacter pylori cagA gene promoter region has been linked to variation in CagA expression and gastric histopathology. Here, we characterized the cagA promoter and expression in 46 H. pylori strains from Portugal. Our results confirm the relationship between cagA promoter region variation and protein expression originally observed in strains from Colombia. We observed that individuals with intestinal metaplasia were all infected with H. pylori strains containing a specific cagA motif. Additionally, we provided novel functional evidence that strain-specific sequences in the cagA promoter region and CagA expression levels influence interleukin 8 secretion by the host gastric epithelial cells., (© The Author 2015. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.)

The impairment of salivary glands activity is often connected to the complaints of dry-mouth and subsequent degradation of the periodontium of diabetic patients. In this context, submandibular glands (SMGs) play a central role in saliva production and so the understanding of the molecular pathways affected is of paramount importance. Using a streptozotocin-induced hyperglycemia rat model and two different time points (2 and 4 months), we applied mass spectrometry-based proteomic techniques, validated with standard western blot analysis, to identify and quantify the effect of chronic hyperglycemia on the proteome of SMGs. We observed significant variations of proteins such as kallikreins, protein S100A6 or annexins. After 2 months of hyperglycemia, we observed an early phase response characterized by a significant increase of protein S100A6, linked to the inflammatory response, together with the impairment of metabolic and energy production processes. On the other hand, vesicular transport appeared to be favoured in such conditions. Interestingly, in a long-term response to hyperglycemia after 4 months of exposure, we observed a general attenuation of the variations. In conclusion, we present data that support the existence of an adaptation of the gland to long-term stress.

Background: Helicobacter pylori induces an invasive phenotype in gastric epithelial cells through a mechanism that requires the type IV secretion system and the phosphorylation of c-Met. The E-cadherin-catenin complex is a major component of the adherens junctions and functions as an invasion suppressor. We investigated whether E-cadherin has a role in H. pylori-induced, c-Met phosphorylation-dependent cell-invasive phenotype., Methods: AGS cells that lack E-cadherin and that are invasive to H. pylori stimulation were transduced with E-cadherin and infected with H. pylori. NCI-N87 cells, which endogenously express E-cadherin, were also used for infection experiments., Results: E-cadherin was sufficient to suppress not only H. pylori-mediated cell-invasive phenotype but also c-Met and p120-catenin tyrosine phosphorylation. H. pylori infection led to increased interactions between E-cadherin and p120-catenin, c-Met and E-cadherin, and c-Met and p120-catenin. Using in vitro infection assays, we showed that H. pylori CagA interacts with E-cadherin, p120-catenin, and c-Met. Finally, using small interfering RNA, we showed that interactions between CagA and E-cadherin and between CagA and p120-catenin were established through c-Met., Conclusions: We suggest that H. pylori alters the E-cadherin-catenin complex, leading to formation of a multiproteic complex composed of CagA, c-Met, E-cadherin, and p120-catenin. This complex abrogates c-Met and p120-catenin tyrosine phosphorylation and suppresses the cell-invasive phenotype induced by H. pylori.

Isolates of Mycobacterium tuberculosis from 120 tuberculosis patients seen in the 12 months ending September 1994 at 2 tertiary-care centres in Rio de Janeiro were characterized by IS6110 restriction fragment length polymorphism (RFLP) analysis. Ninety-seven patients (81%) had isolates with unique RFLP patterns, while 23 patients (19%) had isolates that belonged to 11 different RFLP cluster patterns. The strains from the latter patients were distributed among 1 group of 3 patients and 10 groups of 2 patients each. The cluster-pattern strains were not associated with gender, age, HIV infection, type of residence, living in shelter, homelessness or previous history of tuberculosis. However, clustering was strongly associated with multidrug resistance (P = 0.006). These data suggest that recent exogenous transmission may be important for the development of new cases of multidrug-resistant disease in patients attending tertiary-care centres in Rio de Janeiro, Brazil.