Serum methylarginines and spirometry-measured lung function in older adults

Rationale: Methylarginines are endogenous nitric oxide synthase inhibitors that have been implicated in animal models of lung disease but have not previously been examined for their association with spirometric measures of lung function in humans. Objectives: This study measured serum concentrations of asymmetric and symmetric dimethylarginine in a representative sample of older community-dwelling adults and determined their association with spirometric lung function measures. Methods: Data on clinical, lifestyle, and demographic characteristics, methylated arginines, and L-arginine (measured using LC-MS/MS) were collected from a population-based sample of older Australian adults from the Hunter Community Study. The five key lung function measures included as outcomes were Forced Expiratory Volume in 1 second, Forced Vital Capacity, Forced Expiratory Volume in 1 second to Forced Vital Capacity ratio, Percent Predicted Forced Expiratory Volume in 1 second, and Percent Predicted Forced Vital Capacity. Measurements and Main Results: In adjusted analyses there were statistically significant independent associations between a) higher asymmetric dimethylarginine, lower Forced Expiratory Volume in 1 second and lower Forced Vital Capacity; and b) lower L-arginine/asymmetric dimethylarginine ratio, lower Forced Expiratory Volume in 1 second, lower Percent Predicted Forced Expiratory Volume in 1 second and lower Percent Predicted Forced Vital Capacity. By contrast, no significant associations were observed between symmetric dimethylarginine and lung function. Conclusions: After adjusting for clinical, demographic, biochemical, and pharmacological confounders, higher serum asymmetric dimethylarginine was independently associated with a reduction in key measures of lung function. Further research is needed to determine if methylarginines predict the decline in lung function

Mass spectrometry imaging identifies palmitoylcarnitine as an immunological mediator during Salmonella Typhimurium infection

Salmonella Typhimurium causes a self-limiting gastroenteritis that may lead to systemic disease. Bacteria invade the small intestine, crossing the intestinal epithelium from where they are transported to the mesenteric lymph nodes (MLNs) within migrating immune cells. MLNs are an important site at which the innate and adaptive immune responses converge but their architecture and function is severely disrupted during S. Typhimurium infection. To further understand host-pathogen interactions at this site, we used mass spectrometry imaging (MSI) to analyse MLN tissue from a murine model of S. Typhimurium infection. A molecule, identified as palmitoylcarnitine (PalC), was of particular interest due to its high abundance at loci of S. Typhimurium infection and MLN disruption. High levels of PalC localised to sites within the MLNs where B and T cells were absent and where the perimeter of CD169+ sub capsular sinus macrophages was disrupted. MLN cells cultured ex vivo and treated with PalC had reduced CD4+CD25+ T cells and an increased number of B220+CD19+ B cells. The reduction in CD4+CD25+ T cells was likely due to apoptosis driven by increased caspase-3/7 activity. These data indicate that PalC significantly alters the host response in the MLNs, acting as a decisive factor in infection outcome

Diagnostic Accuracy of Integrating Ultrasound and Shear Wave Elastography in Assessing Carpal Tunnel Syndrome Severity: a Prospective Observational Study

Ahmed Mohamed El-Maghraby,1 Yassir Edrees Almalki,2 Mohammad Abd Alkhalik Basha,1 Mohamad Gamal Nada,1 Fatma El Ahwany,1 Sharifa Khalid Alduraibi,3 Shaker Hassan S Alshehri,4 Asim S Aldhilan,3 Ziyad A Almushayti,3 Alaa K Alduraibi,3 Mervat Aboualkheir,5 Osama Attia,6 Mona M Amer,7 Ahmed M Abdelkhalik Basha,8 Ibrahim M Eladl1 1Department of Diagnostic Radiology, Faculty of Human Medicine, Zagazig University, Zagazig, 44519, Egypt; 2Division of Radiology, Department of Internal Medicine, Medical College, Najran University, Najran, 61441, Kingdom of Saudi Arabia; 3Department of Radiology, College of Medicine, Qassim University, Buraidah, 52571, Kingdom of Saudi Arabia; 4Department of Orthopedic Surgery, College of Medicine, King Khalid University, Abha, 61421, Kingdom of Saudi Arabia; 5Department of Internal Medicine, College of Medicine, Taibah University, Madinah, 42361 Kingdom of Saudi Arabia; 6Department of Internal Medicine, Faculty of Human Medicine, Zagazig University, Zagazig, 44519, Egypt; 7Department of Neurology, Faculty of Human Medicine, Zagazig University, Zagazig, 44519, Egypt; 8Faculty of General Medicine, Saint Petersburg State University, Egypt Branch, Cairo, 11646, EgyptCorrespondence: Yassir Edrees Almalki, Email [email protected]: Carpal tunnel syndrome (CTS) is a common condition characterized by compression of the median nerve (MN) within the carpal tunnel. Accurate diagnosis and assessment of CTS severity are crucial for appropriate management decisions. This study aimed to investigate the combined diagnostic utility of B-mode ultrasound (US) and shear wave elastography (SWE) for assessing the severity of CTS in comparison to electrodiagnostic tests (EDT).Materials and Methods: This prospective observational study was conducted over 9-month periods at a tertiary care hospital. A total of 48 patients (36 females, 12 males; mean age 44 ± 10.9 years; age range 28– 57 years) with clinically suspected CTS were enrolled. All patients underwent EDT, US, and SWE. Based on the EDT results, CTS cases were categorized into four groups: mild, moderate, severe, and negative. The cross-sectional area (CSA) and elasticity (E) of the MN were measured at the tunnel inlet (CSAu and Eu) and pronator quadratus region (CSAo and Eo). The differences (CSAu-CSAo and Eu-Eo) were calculated. The primary outcomes were the diagnostic performance of CSAu, CSAu-CSAo, Eu, and Eu-Eo in differentiating moderate/severe from mild/negative CTS compared to EDT findings. Secondary outcomes included a correlation of US/SWE parameters with EDT grades and between each other. ANOVA, correlation, regression, and receiver operating characteristic (ROC) curve analyses were performed.Results: CSAu and CSAu–CSAo increased progressively with worsening CTS severity. E measurements were significantly higher in moderate-to-severe CTS compared to mild or negative cases. The combined metric of CSAu-CSAo at a 5 mm threshold exhibited enhanced performance, with a higher sensitivity (83.3%), specificity (100%), and area under the curve (AUC) (0.98), surpassing the results of CSAu when used independently. Similarly, the SWE measurements indicated that Eu-Eo at a 56.1kPa cutoff achieved an AUC of 0.95, with a sensitivity of 93.3% and specificity of 94.4%, outperforming the metrics for Eu when used alone, which had an AUC of 0.93, with identical sensitivity and specificity values (93.3% and 94.4%, respectively).Conclusion: The integration of ultrasound, shear wave elastography, and electrodiagnostic tests provides a comprehensive approach to evaluate anatomical and neurological changes and guide management decisions for CTS.Keywords: carpal tunnel syndrome, median never, ultrasound, shear wave elastograph

The RNA Chaperone Hfq Is Important for Growth and Stress Tolerance in Francisella novicida

The RNA-binding protein Hfq is recognized as an important regulatory factor in a variety of cellular processes, including stress resistance and pathogenesis. Hfq has been shown in several bacteria to interact with small regulatory RNAs and act as a post-transcriptional regulator of mRNA stability and translation. Here we examined the impact of Hfq on growth, stress tolerance, and gene expression in the intracellular pathogen Francisella novicida. We present evidence of Hfq involvement in the ability of F. novicida to tolerate several cellular stresses, including heat-shock and oxidative stresses, and alterations in hfq gene expression under these conditions. Furthermore, expression of numerous genes, including several associated with virulence, is altered in a hfq mutant strain suggesting they are regulated directly or indirectly by Hfq. Strikingly, we observed a delayed entry into stationary phase and increased biofilm formation in the hfq mutant. Together, these data demonstrate a critical role for Hfq in F. novicida growth and survival

Quality of Life and Related Factors among HIV-Positive Spouses from Serodiscordant Couples under Antiretroviral Therapy in Henan Province, China

OBJECTIVE: To describe the quality of life and related factors in HIV-positive spouses undergoing ART from discordant couples. METHODS: A cross-sectional study was conducted among 1,009 HIV-positive spouses from serodiscordant couples in Zhumadian, Henan Province, between October 1, 2008 and March 31, 2009. HIV-positive spouses were interviewed by local health professionals. Quality of life was evaluated by WHOQOL (Chinese Version). A multiple linear regression model was used to analyze the related factors. RESULTS: The majority of subjects were female (56.39%), had received a high school education (44%), were of Han ethnicity (98.41%), and were farmers (90.09%); the median time period of receiving ART was 3.92 years. The physical, psychological, social, and environmental QOL scores of the subjects were 12.91±1.95, 12.35±1.80, 13.96±2.43, and 12.45±1.91 respectively. The multiple linear regression model identified the physical domain related factors to be CD4 count, educational level, and occupation; psychological domain related factors include age, educational level, and reported STD symptom; social domain related factors included education level; and environmental domain related factors included education level, reported STD symptoms, and occupation. CONCLUSION: Being younger, a farmer, having a lower level of education, a reported STD symptom, or lower CD4 count, could decrease one's quality of life, suggesting that the use of blanket ART programs alone may not necessarily improve quality of life. Subjects received lower scores in the psychological domain, suggesting that psychological intervention may also need to be strengthened

Novel Use of Surveillance Data to Detect HIV-Infected Persons with Sustained High Viral Load and Durable Virologic Suppression in New York City

Background: Monitoring of the uptake and efficacy of ART in a population often relies on cross-sectional data, providing limited information that could be used to design specific targeted intervention programs. Using repeated measures of viral load (VL) surveillance data, we aimed to estimate and characterize the proportion of persons living with HIV/AIDS (PLWHA) in New York City (NYC) with sustained high VL (SHVL) and durably suppressed VL (DSVL). Methods/Principal Findings: Retrospective cohort study of all persons reported to the NYC HIV Surveillance Registry who were alive and $12 years old by the end of 2005 and who had$2 VL tests in 2006 and 2007. SHVL and DSVL were defined as PLWHA with 2 consecutive VLs $100,000 copies/mL and PLWHA with all VLs #400 copies/mL, respectively. Logistic regression models using generalized estimating equations were used to model the association between SHVL and covariates. There were 56,836 PLWHA, of whom 7 % had SHVL and 38 % had DSVL. Compared to those without SHVL, persons with SHVL were more likely to be younger, black and have injection drug use (IDU) risk. PLWHA with SHVL were more likely to die by 2007 and be younger by nearly ten years, on average. Conclusions/Significance: Nearly 60 % of PLWHA in 2005 had multiple VLs, of whom almost 40 % had DSVL, suggesting successful ART uptake. A small proportion had SHVL, representing groups known to have suboptimal engagement in care. This group should be targeted for additional outreach to reduce morbidity and secondary transmission. Measures based o

Factors limiting the transmission of HIV mutations conferring drug resistance: fitness costs and genetic bottlenecks

Transmission of HIV strains with drug-resistance mutations (DRMs) causes public health problems in resource-rich countries. We use a stochastic model, with data from viral competition experiments, to analyze the effect of fitness costs (FCs) and genetic bottlenecks on limiting transmission of 10 clinically significant DRMs. Transmission of DRMs with low FCs (∼0.2%) is similar to wild-type; transmission chains last ∼8 generations causing clusters of ∼60 infected individuals. Genetic bottlenecks substantially limit transmission of DRMs with moderately high FCs (∼0.6%); chains last ∼1–3 generations with transmission clusters of 2–7. Transmission of DRMs with extremely high FCs (>6%) only occurs from ∼5% of index cases. DRMs can revert to wild-type and remain as minority strains, within treatment-naïve individuals, undetectable by current resistance assays. We calculate, based on assay sensitivity, the length of time each DRM is detectable within individuals. Taken together, our results imply a hidden epidemic of transmitted resistance may exist

Differential Virulence Gene Expression of Group A Streptococcus Serotype M3 in Response to Co-Culture with Moraxella catarrhalis

Streptococcus pyogenes (group A Streptococcus, GAS) and Moraxella catarrhalis are important colonizers and (opportunistic) pathogens of the human respiratory tract. However, current knowledge regarding colonization and pathogenic potential of these two pathogens is based on work involving single bacterial species, even though the interplay between respiratory bacterial species is increasingly important in niche occupation and the development of disease. Therefore, to further define and understand polymicrobial species interactions, we investigated whether gene expression (and hence virulence potential) of GAS would be affected upon co-culture with M. catarrhalis. For co-culture experiments, GAS and M. catarrhalis were cultured in Todd-Hewitt broth supplemented with 0.2% yeast extract (THY) at 37°C with 5% CO2aeration. Each strain was grown in triplicate so that triplicate experiments could be performed. Bacterial RNA was isolated, cDNA synthesized, and microarray transcriptome expression analysis performed. We observed significantly increased (≥4-fold) expression for genes playing a role in GAS virulence such as hyaluronan synthase (hasA), streptococcal mitogenic exotoxin Z (smeZ) and IgG endopeptidase (ideS). In contrast, significantly decreased (≥4-fold) expression was observed in genes involved in energy metabolism and in 12 conserved GAS two-component regulatory systems. This study provides the first evidence that M. catarrhalis increases GAS virulence gene expression during co-culture, and again shows the importance of polymicrobial infections in directing bacterial virulence

Colorectal cancer risk assessment and screening recommendation: a community survey of healthcare providers' practice from a patient perspective

<p>Abstract</p> <p>Background</p> <p>Family history is a common risk factor for colorectal cancer (CRC), yet it is often underused to guide risk assessment and the provision of risk-appropriate CRC screening recommendation. The aim of this study was to identify from a patient perspective health care providers' current practice relating to: (i) assessment of family history of CRC; (ii) notification of "increased risk" to patients at "moderately/potentially high" familial risk; and (iii) recommendation that patients undertake CRC screening.</p> <p>Methods</p> <p>1592 persons aged 56-88 years randomly selected from the Hunter Community Study (HCS), New South Wales, Australia were mailed a questionnaire. 1117 participants (70%) returned a questionnaire.</p> <p>Results</p> <p>Thirty eight percent of respondents reported ever being asked about their family history of CRC. Ever discussing family history of CRC with a health care provider was significantly more likely to occur for persons with a higher level of education, who had ever received screening advice and with a lower physical component summary score. Fifty one percent of persons at "moderately/potentially high risk" were notified of their "increased risk" of developing CRC. Thirty one percent of persons across each level of risk had ever received CRC screening advice from a health care provider. Screening advice provision was significantly more likely to occur for persons who had ever discussed their family history of CRC with a health care provider and who were at "moderately/potentially high risk".</p> <p>Conclusions</p> <p>Effective interventions that integrate both the assessment and notification of familial risk of CRC to the wider population are needed. Systematic and cost-effective mechanisms that facilitate family history collection, risk assessment and provision of screening advice within the primary health care setting are required.</p

The Moraxella adhesin UspA1 binds to its human CEACAM1 receptor by a deformable trimeric coiled-coil

Moraxella catarrhalis is a ubiquitous human-specific bacterium commonly associated with upper and lower respiratory tract infections, including otitis media, sinusitis and chronic obstructive pulmonary disease. The bacterium uses an autotransporter protein UspA1 to target an important human cellular receptor carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1). Using X-ray crystallography, we show that the CEACAM1 receptor-binding region of UspA1 unusually consists of an extended, rod-like left-handed trimeric coiled-coil. Mutagenesis and binding studies of UspA1 and the N-domain of CEACAM1 have been used to delineate the interacting surfaces between ligand and receptor and guide assembly of the complex. However, solution scattering, molecular modelling and electron microscopy analyses all indicate that significant bending of the UspA1 coiled-coil stalk also occurs. This explains how UspA1 can engage CEACAM1 at a site far distant from its head group, permitting closer proximity of the respective cell surfaces during infection