Elimination of Chlamydia muridarum from the female reproductive tract is IL-12p40 dependent, but independent of Th1 and Th2 cells.

Chlamydia vaccine approaches aspire to induce Th1 cells for optimal protection, despite the fact that there is no direct evidence demonstrating Th1-mediated Chlamydia clearance from the female reproductive tract (FRT). We recently reported that T-bet-deficient mice can resolve primary Chlamydia infection normally, undermining the potentially protective role of Th1 cells in Chlamydia immunity. Here, we show that T-bet-deficient mice develop robust Th17 responses and that mice deficient in Th17 cells exhibit delayed bacterial clearance, demonstrating that Chlamydia-specific Th17 cells represent an underappreciated protective population. Additionally, Th2-deficient mice competently clear cervicovaginal infection. Furthermore, we show that sensing of IFN-γ by non-hematopoietic cells is essential for Chlamydia immunity, yet bacterial clearance in the FRT does not require IFN-γ secretion by CD4 T cells. Despite the fact that Th1 cells are not necessary for Chlamydia clearance, protective immunity to Chlamydia is still dependent on MHC class-II-restricted CD4 T cells and IL-12p40. Together, these data point to IL-12p40-dependent CD4 effector maturation as essential for Chlamydia immunity, and Th17 cells to a lesser extent, yet neither Th1 nor Th2 cell development is critical. Future Chlamydia vaccination efforts will be more effective if they focus on induction of this protective CD4 T cell population.

Circulating immunity protects the female reproductive tract from Chlamydia infection.

Anatomical positioning of memory lymphocytes within barrier tissues accelerates secondary immune responses and is thought to be essential for protection at mucosal surfaces. However, it remains unclear whether resident memory in the female reproductive tract (FRT) is required for Chlamydial immunity. Here, we describe efficient generation of tissue-resident memory CD4 T cells and memory lymphocyte clusters within the FRT after vaginal infection with Chlamydia Despite robust establishment of localized memory lymphocytes within the FRT, naïve mice surgically joined to immune mice, or mice with only circulating immunity following intranasal immunization, were fully capable of resisting Chlamydia infection via the vaginal route. Blocking the rapid mobilization of circulating memory CD4 T cells to the FRT inhibited this protective response. These data demonstrate that secondary protection in the FRT can occur in the complete absence of tissue-resident immune cells. The ability to confer robust protection to barrier tissues via circulating immune memory provides an unexpected opportunity for vaccine development against infections of the FRT.

The mental health of staff working on intensive care units over the COVID-19 winter surge of 2020 in England: a cross sectional survey.

BACKGROUND: The COVID-19 pandemic generated a surge of critically ill patients greater than the capacity of the UK National Health Service (NHS). There have been multiple well-documented impacts associated with the national COVID-19 pandemic surge on ICU staff, including an increased prevalence of mental health disorders on a scale potentially sufficient to impair high-quality care delivery. We investigated the prevalence of five mental health outcomes; explored demographic and professional predictors of poor mental health outcomes; and describe the prevalence of functional impairment; and explore demographic and professional predictors of functional impairment in ICU staff over the 2020/2021 winter COVID-19 surge in England. METHODS: English ICU staff were surveyed before, during, and after the winter 2020/2021 surge using a survey which comprised validated measures of mental health. RESULTS: A total of 6080 surveys were completed, by ICU nurses (57.5%), doctors (27.9%), and other healthcare staff (14.5%). Reporting probable mental health disorders increased from 51% (before) to 64% (during), and then decreased to 46% (after). Younger, less experienced nursing staff were most likely to report probable mental health disorders. During and after the winter, >50% of participants met threshold criteria for functional impairment. Staff who reported probable post-traumatic stress disorder, anxiety, or depression were more likely to meet threshold criteria for functional impairment. CONCLUSIONS: The winter of 2020/2021 was associated with an increase in poor mental health outcomes and functional impairment amongst ICU staff during a period of peak caseload. These effects are likely to impact on patient care outcomes and the longer-term resilience of the healthcare workforce.

Intensive care medicine is 60 years old: the history and future of the intensive care unit.

Intensive care is celebrating its 60th anniversary this year. The concept arose from the devastating Copenhagen polio epidemic of 1952, which resulted in hundreds of victims experiencing respiratory and bulbar failure. Over 300 patients required artificial ventilation for several weeks. This was provided by 1,000 medical and dental students who were employed to hand ventilate the lungs of these patients via tracheostomies. By 1953, Bjorn Ibsen, the anaesthetist who had suggested that positive pressure ventilation should be the treatment of choice during the epidemic, had set up the first intensive care unit (ICU) in Europe, gathering together physicians and physiologists to manage sick patients - many would consider him to be the 'father' of intensive care. Here, we discuss the events surrounding the 1952 polio epidemic, the subsequent development of ICUs throughout the UK, the changes that have occurred in intensive care over the past 10 years and what the future holds for the specialty.

Production of antibodies and antibody fragments containing non-natural amino acids in Escherichia coli.

Therapeutic bioconjugates are emerging as an essential tool to combat human disease. Site-specific conjugation technologies are widely recognized as the optimal approach for producing homogeneous drug products. Non-natural amino acid (nnAA) incorporation allows the introduction of bioconjugation handles at genetically defined locations. Escherichia coli (E. coli) is a facile host for therapeutic nnAA protein synthesis because it can stably replicate plasmids encoding genes for product and nnAA incorporation. Here, we demonstrate that by engineering E. coli to incorporate high levels of nnAAs, it is feasible to produce nnAA-containing antibody fragments and full-length immunoglobulin Gs (IgGs) in the cytoplasm of E. coli. Using high-density fermentation, it was possible to produce both of these types of molecules with site-specifically incorporated nnAAs at titers > 1 g/L. We anticipate this strategy will help simplify the production and manufacture of promising antibody therapeutics.

Human factors and ergonomics.

Human factors and ergonomics in healthcare is an important discipline that considers both the physical and mental characteristics of healthcare workers, as well as the complex interactions within which organisations exist.

An Integrated In Vivo/In Vitro Protein Production Platform for Site-Specific Antibody Drug Conjugates.

The XpressCF+® cell-free protein synthesis system is a robust platform for the production of non-natural amino acids containing antibodies, which enable the site-specific conjugation of homogeneous antibody drug conjugates (ADCs) via click chemistry. Here, we present a robust and scalable means of achieving a 50-100% increase in IgG titers by combining the high productivity of cell-based protein synthesis with the unique ability of XpressCF+® reactions to produce correctly folded and assembled IgGs containing multiple non-natural amino acids at defined positions. This hybrid technology involves the pre-expression of an IgG light-chain (LC) protein in a conventional recombinant E. coli expression system, engineered to have an oxidizing cytoplasm. The prefabricated LC subunit is then added as a reagent to the cell-free protein synthesis reaction. Prefabricated LC increases IgG titers primarily by reducing the protein synthesis burden per IgG since the cell free translation machinery is only responsible for synthesizing the HC protein. Titer increases were demonstrated in four IgG products in scales ranging from 100-µL microplate reactions to 0.25-L stirred tank bioreactors. Similar titer increases with prefabricated LC were also demonstrated for a bispecific antibody in the scFvFc-FabFc format, demonstrating the generality of this approach. Prefabricated LC also increases robustness in cell-free reactions since it eliminates the need to fine-tune the HC-to-LC plasmid ratio, a critical parameter influencing IgG assembly and quality when the two IgG subunits are co-expressed in a single reaction. ADCs produced using prefabricated LC were shown to be identical to IgGs produced in cell-free alone by comparing product quality, in vitro cell killing, and FcRn receptor binding assays. This approach represents a significant step towards improving IgG titers and the robustness of cell-free protein synthesis reactions by integrating in vivo and in vitro protein production platforms.

Cohousing with Dirty Mice Increases the Frequency of Memory T Cells and Has Variable Effects on Intracellular Bacterial Infection.

The presence of memory lymphocytes in nonlymphoid tissues reflects prior immunological experience and can provide nonspecific defense against infection. In this study, we used a mouse cohousing approach to examine the effect of prior immunological experience on Salmonella and Chlamydia infection. As expected, cohousing of "dirty mice" with specific pathogen-free laboratory mice increased the frequency of effector memory T cells in laboratory mice and enhanced protection against systemic Listeria infection. In contrast, the course of systemic infection with Salmonella and mucosal infection with Chlamydia was largely unaffected by cohousing, despite enhanced frequencies of memory T cells. Thus, cohousing of laboratory mice reliably increases the proportion of memory T cells in circulation, but can it have variable effects on pathogen clearance.

Epidemiological modelling in refugee and internally displaced people settlements: challenges and ways forward.

The spread of infectious diseases such as COVID-19 presents many challenges to healthcare systems and infrastructures across the world, exacerbating inequalities and leaving the world's most vulnerable populations at risk. Epidemiological modelling is vital to guiding evidence-informed or data-driven decision making. In forced displacement contexts, and in particular refugee and internally displaced people (IDP) settlements, it meets several challenges including data availability and quality, the applicability of existing models to those contexts, the accurate modelling of cultural differences or specificities of those operational settings, the communication of results and uncertainties, as well as the alignment of strategic goals between diverse partners in complex situations. In this paper, we systematically review the limited epidemiological modelling work applied to refugee and IDP settlements so far, and discuss challenges and identify lessons learnt from the process. With the likelihood of disease outbreaks expected to increase in the future as more people are displaced due to conflict and climate change, we call for the development of more approaches and models specifically designed to include the unique features and populations of refugee and IDP settlements. To strengthen collaboration between the modelling and the humanitarian public health communities, we propose a roadmap to encourage the development of systems and frameworks to share needs, build tools and coordinate responses in an efficient and scalable manner, both for this pandemic and for future outbreaks.

Sentiments Regarding COVID-19 Vaccination among Graduate Students in Singapore.

As the COVID-19 pandemic rages unabated, and with more infectious variants, vaccination may offer a way to transit out of strict restrictions on physical human interactions to curb the virus spread and prevent overwhelming the healthcare system. However, vaccine hesitancy threatens to significantly impact our progress towards achieving this. It is thus important to understand the sentiments regarding vaccination for different segments of the population to facilitate the development of effective strategies to persuade these groups. Here, we surveyed the COVID-19 vaccination sentiments among a highly educated group of graduate students from the National University of Singapore (NUS). Graduate students who are citizens of 54 different countries, mainly from Asia, pursue studies in diverse fields, with 32% expressing vaccine hesitancy. Citizenship, religion, country of undergraduate/postgraduate studies, exposure risk and field of study are significantly associated with vaccine sentiments. Students who are Chinese citizens or studied in Chinese Universities prior to joining NUS are more hesitant, while students of Indian descent or studied in India are less hesitant about vaccination. Side effects, safety issues and vaccine choice are the major concerns of the hesitant group. Hence, this study would facilitate the development of strategies that focus on these determinants to enhance vaccine acceptance.

June: open-source individual-based epidemiology simulation.

We introduce June, an open-source framework for the detailed simulation of epidemics on the basis of social interactions in a virtual population constructed from geographically granular census data, reflecting age, sex, ethnicity and socio-economic indicators. Interactions between individuals are modelled in groups of various sizes and properties, such as households, schools and workplaces, and other social activities using social mixing matrices. June provides a suite of flexible parametrizations that describe infectious diseases, how they are transmitted and affect contaminated individuals. In this paper, we apply June to the specific case of modelling the spread of COVID-19 in England. We discuss the quality of initial model outputs which reproduce reported hospital admission and mortality statistics at national and regional levels as well as by age strata.

Variability in COVID-19 in-hospital mortality rates between national health service trusts and regions in England: A national observational study for the Getting It Right First Time Programme.

BACKGROUND: A key first step in optimising COVID-19 patient outcomes during future case-surges is to learn from the experience within individual hospitals during the early stages of the pandemic. The aim of this study was to investigate the extent of variation in COVID-19 outcomes between National Health Service (NHS) hospital trusts and regions in England using data from March-July 2020. METHODS: This was a retrospective observational study using the Hospital Episode Statistics administrative dataset. Patients aged ≥ 18 years who had a diagnosis of COVID-19 during a hospital stay in England that was completed between March 1st and July 31st, 2020 were included. In-hospital mortality was the primary outcome of interest. In secondary analysis, critical care admission, length of stay and mortality within 30 days of discharge were also investigated. Multilevel logistic regression was used to adjust for covariates. FINDINGS: There were 86,356 patients with a confirmed diagnosis of COVID-19 included in the study, of whom 22,944 (26.6%) died in hospital with COVID-19 as the primary cause of death. After adjusting for covariates, the extent of the variation in-hospital mortality rates between hospital trusts and regions was relatively modest. Trusts with the largest baseline number of beds and a greater proportion of patients admitted to critical care had the lowest in-hospital mortality rates. INTERPRETATION: There is little evidence of clustering of deaths within hospital trusts. There may be opportunities to learn from the experience of individual trusts to help prepare hospitals for future case-surges.

Pancreatogenic Diabetes, 2 Onset Forms and Lack of Metabolic Syndrome Components Differentiate It From Type 2 Diabetes.

OBJECTIVES: We compared pancreatogenic (DM3c) and type 2 diabetes mellitus. METHODS: We compared age-, sex-, and diabetes mellitus duration-matched DM3c cases (n = 142) and type 2 diabetes mellitus (n = 142). Pancreatogenic diabetes was considered when it appeared after the diagnosis of pancreatitis or after pancreatic surgery. RESULTS: Pancreatogenic diabetes presented lower body mass index (BMI) [odds ratio (OR), 1.2; 95% confidence interval (CI), 1.13-1.28; P < 0.001], worse glycemic control (OR, 1.196; 95% CI, 1.058-1.35; P = 0.004), required insulin more frequently (OR, 4.21; 95% CI, 2.57-6.93; P = 0.0001), had more hypoglycemic episodes (OR, 3.65; 95% CI, 1.64-8.16; P = 0.001) but lower frequency of dyslipidemia (OR, 0.42; 95% CI, 0.26-0.68; P = 0.001) and arterial hypertension (OR, 0.52; 95% CI, 0.32-0.86; P = 0.01). Pancreatogenic diabetes cases on pancreatic enzyme replacement therapy had lower glycosylated hemoglobin (8.52% vs 9.44%; P = 0.026), serum carotenes (79.1 vs 116.1; P = 0.03), and BMI (23.4 vs 26.1; P = 0.0005) than those not on pancreatic enzyme replacement therapy. Pancreatogenic diabetes onset occurred earlier in necrotizing pancreatitis and after pancreatic surgery. CONCLUSIONS: Pancreatogenic diabetes presents with low BMI and lacks metabolic syndrome components. The type of pancreatic disease or surgery defines its onset time.

The influence of online video learning aids on preparing postgraduate chiropractic students for an objective structured clinical examination.

OBJECTIVE: To investigate the influence of providing online procedural videos to postgraduate chiropractic students preparing for an objective structured clinical examination (OSCE). METHODS: Eighty-three postgraduate chiropractic students enrolled in a diagnostic unit during 2017 received supplemental video resources prior to their final OSCE. Ninety students enrolled in the 2016 offering of the unit acted as the control group. Two-sample t tests were used to compare OSCE results between groups and paired t tests were used for within-group comparisons. Regression analysis was used to examine the association of age, undergraduate grade point average, and gender with the final OSCE scores. Students were also surveyed regarding their perceptions of the video resources using a purpose-built questionnaire. RESULTS: A paired t test comparing initial and final OSCE scores found a small but significant increase in scores for the 2017 (mean change 3.6 points; p = .001) but not the 2016 (mean change -1.1 scores; p = .09) cohort. The 2017 cohort had significantly more change than the 2016 cohort (mean difference 4.7 points; p < .001). Analysis of responses to the questionnaire highlighted overall positive feedback for the procedural videos. CONCLUSION: Online procedural videos as learning resources had a small but positive effect on OSCE performance for a group of postgraduate chiropractic students. Students perceived the resource as being helpful for OSCE preparation.

Evaluation of bone densitometry by dual-energy x-ray absorptiometry as a fracture prediction tool in women with chronic kidney disease.

BACKGROUND: The 2017 KDIGO guidelines establish a 2B grade recommendation in favor of testing Bone Mineral Density (BMD) by DXA to assess osteoporotic fracture (OPF) risk in patients with CKD G3a-G5D. Still, controversy remains because large studies evaluating it for this particular population are lacking. AIM: To establish the clinical performance of BMD measured by DXA in the evaluation of fracture risk in women with CKD. METHODS: We conducted a 43 year retrospective cohort study with 218 women ≥18 years-old with CKD and BMD measurement by DXA of total hip and lumbar spine. Clinical (age, year of CKD onset, comorbidities, BMI, transplant status, treatment), and biochemical (PTH, corrected calcium, phosphate, vitamin D [25 (OH) D3], creatinine, and albumin), parameters were collected from hospital records. All osteoporotic fractures (as defined by the WHO) found in the clinical and radiologic files were registered. RESULTS: 218 women with a median age of 60 years (40-73 IQ range) and a CKD evolution time of 12 years (7-18 IQ range) were evaluated. Forty-eight (28.23%) presented an OPF. These women were older (57 vs 69 years, p =0.0072) and had a lower BMD. CKD stage did not influence fracture incidence. In the multivariate analysis we found that for each standard deviation decrease in hip and lumbar spine T-Score, the overall fracture risk was 2.7 and 2.04 times higher, respectively. More than 50% of fractures took place within the first ten years of follow-up, especially with GFR <30 mL/min/m2 and osteoporosis. Diabetes and hypothyroidism accelerated fracture onset, while renal transplant delayed it. In the ROC analysis, the AUC was largest with the total hip (0.7098, p = 0.000) and lumbar spine (0.6916, p = 0.000). CONCLUSIONS: BMD measured by DXA is a useful fracture prediction tool for women with CKD, having a sensibility and specificity similar to that in the general population. It seems to be appropriate for the diagnosis, treatment decisions, and follow-up of patients with renal failure.

Survival following Treatment of Aortoesophageal Fistula with Dual Esophageal and Aortic Intervention.

Aortoesophageal fistulas are a rare but commonly fatal complication of esophageal cancer. Reports of successfully managed cases are few, with high mortality and morbidity usually resulting from failure to control the initial massive haemodynamic insult. We report the case of a 47-year-old Caucasian man with recently diagnosed advanced esophageal cancer who suffered an episode of massive haematemesis. Emergency gastroscopy revealed an arterial bleeding point in the proximal esophagus. A self-expanding metal esophageal stent was placed to achieve initial partial haemostasis. CT angiography confirmed an aortoesophageal fistula. An endoluminal stent device was thus inserted within the thoracic aorta stabilising the bleeding point. The patient subsequently made an uneventful recovery and was discharged on long-term antibiotics for palliative care. He survived for 2 months at home before dying of disseminated malignancy. The successful use of esophageal stenting as a means of achieving haemostasis, allowing time for endovascular intervention, is as yet a relatively unexplored area of management of this rare condition.