Respiratory mucosal immune memory to SARS-CoV-2 after infection and vaccination

Respiratory mucosal immunity induced by vaccination is vital for protection from coronavirus infection in animal models. In humans, the capacity of peripheral vaccination to generate sustained immunity in the lung mucosa, and how this is influenced by prior SARS-CoV-2 infection, is unknown. Here we show using bronchoalveolar lavage samples that donors with history of both infection and vaccination have more airway mucosal SARS-CoV-2 antibodies and memory B cells than those only vaccinated. Infection also induces populations of airway spike-specific memory CD4+ and CD8+ T cells that are not expanded by vaccination alone. Airway mucosal T cells induced by infection have a distinct hierarchy of antigen specificity compared to the periphery. Spike-specific T cells persist in the lung mucosa for 7 months after the last immunising event. Thus, peripheral vaccination alone does not appear to induce durable lung mucosal immunity against SARS-CoV-2, supporting an argument for the need for vaccines targeting the airways

Burden of disease in Thailand: changes in health gap between 1999 and 2004

<p>Abstract</p> <p>Background</p> <p>Continuing comprehensive assessment of population health gap is essential for effective health planning. This paper assessed changes in the magnitude and pattern of disease burden in Thailand between 1999 and 2004. It further drew lessons learned from applying the global burden of disease (GBD) methods to the Thai context for other developing country settings.</p> <p>Methods</p> <p>Multiple sources of mortality and morbidity data for both years were assessed and used to estimate Disability-Adjusted Life Years (DALYs) loss for 110 specific diseases and conditions relevant to the country's health problems. Causes of death from national vital registration were adjusted for misclassification from a verbal autopsy study.</p> <p>Results</p> <p>Between 1999 and 2004, DALYs loss per 1,000 population in 2004 slightly decreased in men but a minor increase in women was observed. HIV/AIDS maintained the highest burden for men in both 1999 and 2004 while in 2004, stroke took over the 1999 first rank of HIV/AIDS in women. Among the top twenty diseases, there was a slight increase of the proportion of non-communicable diseases and two out of three infectious diseases revealed a decrease burden except for lower respiratory tract infections.</p> <p>Conclusion</p> <p>The study highlights unique pattern of disease burden in Thailand whereby epidemiological transition have occurred as non-communicable diseases were on the rise but burden from HIV/AIDS resulting from the epidemic in the 1990s remains high and injuries show negligent change. Lessons point that assessing DALY over time critically requires continuing improvement in data sources particularly on cause of death statistics, institutional capacity and long term commitments.</p

HIV-1 subtype A infection in a community of intravenous drug users in Pakistan

BACKGROUND: Data on the subtypes of HIV in a population help in predicting the potential foci of epidemic, tracking the routes of infection and following the patterns of the virus' genetic divergence. Globally, the most prevalent HIV infection is the HIV-1 subtype C. In Asia, predominant subtypes of HIV-1 are B, C, and CRF-01AE. During the last few years, HIV prevalence in Pakistan has taken the form of a concentrated epidemic in at least two high risk groups, namely, Intravenous Drug Users (IDUs) and Male Sex Workers (MSWs). Factors that have facilitated the proliferation of HIV infection include transmission through a large number of repatriates and needle-sharing intravenous drug users, unscreened blood transfusions, and sexual illiteracy. The HIV subtypes infecting Pakistani populations have not been explored to date. In this study, we analyzed HIV-1 subtypes from in a high-risk community of IDUs in Karachi, the largest city of Pakistan. METHODS: Samples were collected from 34 IDUs after their informed consent. In addition, the study subjects were administered a questionnaire regarding their sexual behavior and travel history. For HIV analysis, DNA was extracted from the samples and analyzed for HIV types and subtypes using subtype-specific primers in a nested polymerase chain reaction (PCR). The results from this PCR were further confirmed using the Heteroduplex Mobility Assay (HMA). RESULTS: We found HIV-1 subtype A in all the 34 samples analyzed. A few of the study subjects were found to have a history of travel and stay in the United Arab Emirates. The same subjects also admitted to having contact with commercial sex workers during their stay abroad. CONCLUSION: Our study therefore shows clade A HIV-1 to be prevalent among the IDUs in Karachi. As the prevalence of HIV in Pakistan continues to rise, more work needs to be done to track the infection, and to analyze the strains of HIV spreading through the country

Gestational Valproate Alters BOLD Activation in Response to Complex Social and Primary Sensory Stimuli

Valproic acid (VPA) has been used clinically as an anticonvulsant medication during pregnancy; however, it poses a neurodevelopmental risk due to its high teratogenicity. We hypothesized that midgestational (GD) exposure to VPA will lead to lasting deficits in social behavior and the processing of social stimuli. To test this, animals were given a single IP injection of 600 mg/kg of VPA on GD 12.5. Starting on postnatal day 2 (PND2), animals were examined for physical and behavior abnormalities. Functional MRI studies were carried out after PND60. VPA and control animals were given vehicle or a central infusion of a V1a antagonist 90 minutes before imaging. During imaging sessions, rats were presented with a juvenile test male followed by a primary visual stimulus (2 Hz pulsed light) to examine the effects of prenatal VPA on neural processing. VPA rats showed greater increases in BOLD signal response to the social stimulus compared to controls in the temporal cortex, thalamus, midbrain and the hypothalamus. Blocking the V1a receptor reduced the BOLD response in VPA animals only. Neural responses to the visual stimulus, however, were lower in VPA animals. Blockade with the V1a antagonist did not revert this latter effect. Our data suggest that prenatal VPA affects the processing of social stimuli and perhaps social memory, partly through a mechanism that may involve vasopressin V1a neurotransmission

Hypoxia increases the metastatic ability of breast cancer cells via upregulation of CXCR4

<p>Abstract</p> <p>Background</p> <p>Chemokine SDF1α and its unique receptor CXCR4 have been implicated in organ-specific metastases of many cancers including breast cancer. Hypoxia is a common feature of solid tumors and is associated with their malignant phenotype. We hypothesized that hypoxia would upregulate CXCR4 expression and lead to increased chemotactic responsiveness to its specific ligand SDF1α.</p> <p>Methods</p> <p>Three breast cancer cell lines MDA-MB-231, MCF7 and 4T1 were subjected to 48 hrs of hypoxia or normoxia. Cell surface receptor expression was evaluated using flow cytometry. An extracellular matrix invasion assay and microporous migration assay was used to assess chemotactic response and metastatic ability.</p> <p>Results</p> <p>CXCR4 surface expression was significantly increased in the two human breast cancer cell lines, MDA-MB-231 and MCF7, following exposure to hypoxia. This upregulation of CXCR4 cell surface expression corresponded to a significant increase in migration and invasion in response to SDF1-α <it>in vitro</it>. The increase in metastatic potential of both the normoxic and the hypoxic treated breast cancer cell lines was attenuated by neutralization of CXCR4 with a CXCR4 neutralizing mAb, MAB172 or a CXCR4 antagonist, AMD3100, showing the relationship between CXCR4 overexpression and increased chemotactic responsiveness.</p> <p>Conclusions</p> <p>CXCR4 expression can be modulated by the tissue microenvironment such as hypoxia. Upregulation of CXCR4 is associated with increased migratory and invasive potential and this effect can be abrogated by CXCR4 inhibition. Chemokine receptor CXCR4 is a potential therapeutic target in the adjuvant treatment of breast cancer.</p

Creating positive environmental impact through citizen science

Interest in citizen science is growing, including from governments and research funders. This interest is often driven by a desire for positive environmental impact, and the expectation that citizen science can deliver it by engaging the public and simultaneously collecting environmental data. Yet, in practice, there is often a gap between expected and realised impact. To close this gap, we need to better understand pathways to impact and what it takes to realise them. We articulate six key pathways through which citizen science can create positive environmental change: (1) environmental management; (2) evidence for policy; (3) behaviour change; (4) social network championing; (5) political advocacy; and (6) community action. We explore the project attributes likely to create impact through each of these pathways and show that there is an interplay between these project attributes and the needs and motivations of target participant groups. Exploring this interplay, we create a framework that articulates four citizen science approaches that create environmental impact in different ways: place-based community action; interest group investigation; captive learning research; and mass participation census

Heritable symbionts in a world of varying temperature

Heritable microbes represent an important component of the biology, ecology and evolution of many plants, animals and fungi, acting as both parasites and partners. In this review, we examine how heritable symbiont–host interactions may alter host thermal tolerance, and how the dynamics of these interactions may more generally be altered by thermal environment. Obligate symbionts, those required by their host, are considered to represent a thermally sensitive weak point for their host, associated with accumulation of deleterious mutations. As such, these symbionts may represent an important determinant of host thermal envelope and spatial distribution. We then examine the varied relationship between thermal environment and the frequency of facultative symbionts that provide ecologically contingent benefits or act as parasites. We note that some facultative symbionts directly alter host thermotolerance. We outline how thermal environment will alter the benefits/costs of infection more widely, and additionally modulate vertical transmission efficiency. Multiple patterns are observed, with symbionts being cold sensitive in some species and heat sensitive in others, with varying and non-coincident thresholds at which phenotype and transmission are ablated. Nevertheless, it is clear that studies aiming to predict ecological and evolutionary dynamics of symbiont–host interactions need to examine the interaction across a range of thermal environments. Finally, we discuss the importance of thermal sensitivity in predicting the success/failure of symbionts to spread into novel species following natural/engineered introduction

A survey of tuberculosis infection control practices at the NIH/NIAID/DAIDS-supported clinical trial sites in low and middle income countries

BACKGROUND: Health care associated transmission of Mycobacterium tuberculosis (TB) is well described. A previous survey of infection control (IC) practices at clinical research sites in low and middle income countries (LMIC) funded by the National Institute of Allergy and Infectious Diseases (NIAID) conducting HIV research identified issues with respiratory IC practices. A guideline for TB IC based on international recommendations was developed and promulgated. This paper reports on adherence to the guideline at sites conducting or planning to conduct TB studies with the intention of supporting improvement. METHODS: A survey was developed that assessed IC activities in three domains: facility level measures, administrative control measures and environmental measures. An external site monitor visited each site in 2013–2014, to complete the audit. A central review committee evaluated the site-level survey and results were tabulated. Fisher’s exact test was performed to determine whether there were significant differences in practices at sites that had IC officers versus sites that did not have IC officers. Significance was assessed at p</=.05 RESULTS: Seven of thirty-three sites surveyed (22 %) had all the evaluated tuberculosis IC (TB IC) elements in place. Sixty-one percent of sites had an IC officer tasked with developing and maintaining TB IC standard operating procedures. Twenty-two (71 %) sites promptly identified and segregated individuals with TB symptoms. Thirty (93 %) sites had a separate waiting area for patients, and 26 (81 %) collected sputum within a specific well-ventilated area that was separate from the general waiting area. Sites with an IC officer were more likely to have standard operating procedures covering TB IC practices (p = 0.02) and monitor those policies (p = 0.02) and perform regular surveillance of healthcare workers (p = 0.02). The presence of an IC officer had a positive impact on performance in most of the TB IC domains surveyed including having adequate ventilation (p = 0.02) and a separate area for sputum collection (p = 0.02) CONCLUSIONS: Specific and targeted support of TB IC activities in the clinical research environment is needed and is likely to have a positive and sustained impact on preventing the transmission of TB to both health care workers and vulnerable HIV-infected research participants. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12879-016-1579-y) contains supplementary material, which is available to authorized users