Urethrocutaneous fistulas after voluntary medical male circumcision for HIV prevention-15 African Countries, 2015-2019.

BACKGROUND: Voluntary medical male circumcision (VMMC) is an HIV prevention strategy recommended to partially protect men from heterosexually acquired HIV. From 2015 to 2019, the President's Emergency Plan for AIDS Relief (PEPFAR) has supported approximately 14.9 million VMMCs in 15 African countries. Urethrocutaneous fistulas, abnormal openings between the urethra and penile skin through which urine can escape, are rare, severe adverse events (AEs) that can occur with VMMC. This analysis describes fistula cases, identifies possible risks and mechanisms of injury, and offers mitigation actions. METHODS: Demographic and clinical program data were reviewed from all reported fistula cases during 2015 to 2019, descriptive analyses were performed, and an odds ratio was calculated by patient age group. RESULTS: In total, 41 fistula cases were reported. Median patient age for fistula cases was 11 years and 40/41 (98%) occurred in patients aged < 15 years. Fistulas were more often reported among patients < 15 compared to ≥ 15 years old (0.61 vs. 0.01 fistulas per 100,000 VMMCs, odds ratio 50.9 (95% confidence interval [CI] = 8.6-2060.0)). Median time from VMMC surgery to appearance of fistula was 20 days (interquartile range (IQR) 14-27). CONCLUSIONS: Urethral fistulas were significantly more common in patients under age 15 years. Thinner tissue overlying the urethra in immature genitalia may predispose boys to injury. The delay between procedure and symptom onset of 2-3 weeks indicates partial thickness injury or suture violation of the urethral wall as more likely mechanisms of injury than intra-operative urethral transection. This analysis helped to inform PEPFAR's recent decision to change VMMC eligibility policy in 2020, raising the minimum age to 15 years.

Brief Report: Modeling the Impact of Voluntary Medical Male Circumcision on Cervical Cancer in Uganda.

BACKGROUND: In addition to providing millions of men with lifelong lower risk for HIV infection, voluntary medical male circumcision (VMMC) also provides female partners with health benefits including decreased risk for human papillomavirus (HPV) and resultant cervical cancer (CC). SETTING: We modeled potential impacts of VMMC on CC incidence and mortality in Uganda as an additional benefit beyond HIV prevention. METHODS: HPV and CC outcomes were modeled using the CC model from the Spectrum policy tool suite, calibrated for Uganda, to estimate HPV infection incidence and progression to CC, using a 50-year (2018-2067) time horizon. 2016 Demographic Health Survey data provided baseline VMMC coverage. The baseline (no VMMC scale-up beyond current coverage, minimal HPV vaccination coverage) was compared with multiple scenarios to assess the varying impact of VMMC according to different implementations of HPV vaccination and HPV screening programs. RESULTS: Without further intervention, annual CC incidence was projected to rise from 16.9 to 31.2 per 100,000 women in 2067. VMMC scale-up alone decreased 2067 annual CC incidence to 25.3, averting 13,000 deaths between 2018 and 2067. With rapidly-achieved 90% HPV9 vaccination coverage for adolescent girls and young women, 2067 incidence dropped below 10 per 100,000 with or without a VMMC program. With 45% vaccine coverage, the addition of VMMC scaleup decreased incidence by 2.9 per 100,000 and averted 8000 additional deaths. Similarly, with HPV screen-and-treat without vaccination, the addition of VMMC scaleup decreased incidence by 5.1 per 100,000 and averted 10,000 additional deaths. CONCLUSIONS: Planned VMMC scale-up to 90% coverage from current levels could prevent a substantial number of CC cases and deaths in the absence of rapid scale-up of HPV vaccination to 90% coverage.

The Role of Nurses and Midwives in Expanding and Sustaining Voluntary Medical Male Circumcision Services for HIV Prevention: A Systematic and Policy Review.

ABSTRACT: Male circumcision reduces men's risk of acquiring HIV through heterosexual sex, and voluntary medical male circumcision (VMMC) is central to HIV prevention strategies in 15 sub-Saharan African countries. Nurses have emerged as primary VMMC providers; however, barriers remain to institutionalizing nurse-led VMMC. Patient safety concerns have hindered task sharing, and regulations governing nurse-performed VMMC are not always supportive or clear. We performed a systematic review on VMMC safety by provider cadre and a desk review of national policies governing the VMMC roles of nurses and midwives. Also, VMMC by nurses is safe and has become standard practice. Countries had multiple policy combinations among different documents, with only one disallowing VMMC by these cadres. Countries with alignment between policies often ensured that nursing workforces were equipped with clinical competencies through national certification. Regulatory clarity and formalized certification for nurse-performed VMMC can increase program sustainability and build nursing capacity to meet other critical basic surgical needs.

The Poststroke Peripheral Immune Response Is Differentially Regulated by Leukemia Inhibitory Factor in Aged Male and Female Rodents.

BACKGROUND: The goal of this study was to determine whether leukemia inhibitory factor (LIF) promotes anti-inflammatory activity after stroke in a sex-dependent manner. METHODS: Aged (18-month-old) Sprague-Dawley rats of both sexes underwent sham surgery or permanent middle cerebral artery occlusion (MCAO). Animals received three doses of intravenous LIF (125 µg/kg) or PBS at 6, 24, and 48 h before euthanization at 72 h. Spleen weights were measured immediately following euthanization. Western blot was used to measure protein levels of CCL8, CD11b, CXCL9, CXCL10, IL-12 p40, IL-3, and the LIF receptor (LIFR) in spleen tissue. ELISA was used to measure IL-1ß, IL-6, TNFα, and IFNγ in spleen tissue. A Griess Assay was used to indirectly quantify NO levels via measurement of nitrite. Levels of cellular markers and inflammatory mediators were normalized to the baseline (sham) group from each sex. Statistical analysis was performed using two-way ANOVA and followed by Fisher's LSD post hoc test. RESULTS: Aged female rats showed a significantly lower spleen weight after MCAO, but showed a significant increase in spleen size after LIF treatment. This effect was observed in aged male rats, but not to as great of an extent. CD11b levels were significantly higher in the spleens of MCAO+PBS males compared to their female counterparts, but there was no significant difference in CD11b levels between MCAO+LIF males and females. LIF significantly increased CXCL9 after LIF treatment in aged male and female rats. LIFR and IL-3 were upregulated after LIF treatment in aged females. Splenic nitrate increased after MCAO but decreased after LIF treatment in aged females. Splenic nitrate levels did not increase after MCAO but did increase after LIF treatment in aged males. The following cytokines/chemokines were not altered by sex or treatment: TNFα, IL-6, IL-12 p40, CCL8, IFNγ, and CXCL10. CONCLUSIONS: LIF treatment after permanent MCAO induces sex-dependent effects on the poststroke splenic response and the production of proinflammatory cytokines among aged rats.

Neuroprotective activity of leukemia inhibitory factor is relayed through myeloid zinc finger-1 in a rat model of stroke.

The aim of this study was to determine whether leukemia inhibitory factor (LIF) exerts its neuroprotective effects through signal transduction of the transcription factor myeloid zinc finger-1 (MZF-1). According to the hypothesis of this study, MZF-1 mediates LIF-induced neuroprotective signaling during ELVO through increased expression and transcriptional activity. To determine the in vivo role of MZF-1 in LIF-induced neuroprotection, we used Genomatix software was used to MZF-1 sites in the promoter region of the rat superoxide dismutase 3 (SOD3) gene. Stroke was induced via middle cerebral artery occlusion, and animals were administered PBS or 125 µg/kg LIF at 6, 24, and 48 h after the injury. MZF-1 binding activity was measured using electrophoretic mobility shift assay (EMSA) and its expression/localization were determined using western blot and immunohistochemical analysis. To determine whether MZF-1 relays LIF-induced neuroprotection in vitro, primary cultured neurons were subjected to oxygen-glucose deprivation (OGD) after treatment with PBS or LIF. MZF-1 expression was measured in vitro using real time PCR and immunohistochemical staining. Transfection with siRNA was used to determine whether LIF protected cultured neurons against OGD after silencing MZF-1 expression. Four MZF-1 binding sites were identified by Genomatix, and EMSA confirmed in vivo binding activity in brain after MCAO. LIF significantly increased MZF-1 protein levels compared to PBS treatment at 72 h post-MCAO. In vivo nuclear localization of MZF-1 as well as co-localization of SOD3 and MZF-1 was observed in the cortical neurons of LIF-treated rats. Primary cultured neurons treated with LIF had significantly higher levels of MZF-1 mRNA and protein after LIF treatment compared to neurons treated with PBS. Finally, knockdown MZF-1 using siRNA counteracted the neuroprotective effects of LIF in vitro. These data demonstrate that LIF-mediated neuroprotection is dependent upon MZF-1 activity. Furthermore, these findings identify a novel neuroprotective pathway that employs MZF-1, a transcription factor associated with hematopoietic gene expression.

Efficacy of leukemia inhibitory factor as a therapeutic for permanent large vessel stroke differs among aged male and female rats.

Preclinical studies using rodent models of stroke have had difficulty in translating their results to human patients. One possible factor behind this inability is the lack of studies utilizing aged rodents of both sexes. Previously, this lab showed that leukemia inhibitory factor (LIF) promoted recovery after stroke through antioxidant enzyme upregulation. This study examined whether LIF promotes neuroprotection in aged rats of both sexes. LIF did not reduce tissue damage in aged animals, but LIF-treated female rats showed partial motor skill recovery. The LIF receptor (LIFR) showed membrane localization in young male and aged rats of both sexes after stroke. Although LIF increased neuronal LIFR expression in vitro, it did not increase LIFR in the aged brain. Levels of LIFR protein in brain tissue were significantly downregulated between young males and aged males/females at 72 h after stroke. These results demonstrated that low LIFR expression reduces the neuroprotective efficacy of LIF in aged rodents of both sexes. Furthermore, the ability of LIF to promote motor improvement is dependent upon sex in aged rodents.

The Blood And Clot Thrombectomy Registry And Collaboration (BACTRAC) protocol: novel method for evaluating human stroke.

BACKGROUND: Ischemic stroke research faces difficulties in translating pathology between animal models and human patients to develop treatments. Mechanical thrombectomy, for the first time, offers a momentary window into the changes occurring in ischemia. We developed a tissue banking protocol to capture intracranial thrombi and the blood immediately proximal and distal to it. OBJECTIVE: To develop and share a reproducible protocol to bank these specimens for future analysis. METHODS: We established a protocol approved by the institutional review board for tissue processing during thrombectomy (www.clinicaltrials.gov NCT03153683). The protocol was a joint clinical/basic science effort among multiple laboratories and the NeuroInterventional Radiology service line. We constructed a workspace in the angiography suite, and developed a step-by-step process for specimen retrieval and processing. RESULTS: Our protocol successfully yielded samples for analysis in all but one case. In our preliminary dataset, the process produced adequate amounts of tissue from distal blood, proximal blood, and thrombi for gene expression and proteomics analyses. We describe the tissue banking protocol, and highlight training protocols and mechanics of on-call research staffing. In addition, preliminary integrity analyses demonstrated high-quality yields for RNA and protein. CONCLUSIONS: We have developed a novel tissue banking protocol using mechanical thrombectomy to capture thrombus along with arterial blood proximal and distal to it. The protocol provides high-quality specimens, facilitating analysis of the initial molecular response to ischemic stroke in the human condition for the first time. This approach will permit reverse translation to animal models for treatment development.

Leukemia inhibitory factor modulates the peripheral immune response in a rat model of emergent large vessel occlusion.

BACKGROUND: The migration of peripheral immune cells and splenocytes to the ischemic brain is one of the major causes of delayed neuroinflammation after permanent large vessel stroke. Other groups have demonstrated that leukemia inhibitory factor (LIF), a cytokine that promotes neural cell survival through upregulation of antioxidant enzymes, promotes an anti-inflammatory phenotype in several types of immune cells. The goal of this study was to determine whether LIF treatment modulates the peripheral immune response after stroke. METHODS: Young male (3 month) Sprague-Dawley rats underwent sham surgery or permanent middle cerebral artery occlusion (MCAO). Animals were administered LIF (125 µg/kg) or PBS at 6, 24, and 48 h prior to euthanization at 72 h. Bone marrow-derived macrophages were treated with LIF (20 ng/ml) or PBS after stimulation with interferon gamma + LPS. Western blot was used to measure protein levels of CD11b, IL-12, interferon inducible protein-10, CD3, and the LIF receptor in spleen and brain tissue. ELISA was used to measure IL-10, IL-12, and interferon gamma. Isolectin was used to label activated immune cells in brain tissue sections. Statistical analysis was performed using one-way ANOVA and Student's t test. A Kruskal-Wallis test followed by Bonferroni-corrected Mann-Whitney tests was performed if data did not pass the D'Agostino-Pearson normality test. RESULTS: LIF-treated rats showed significantly lower levels of the LIF receptor and interferon gamma in the spleen and CD11b levels in the brain compared to their PBS-treated counterparts. Fluorescence from isolectin-binding immune cells was more prominent in the ipsilateral cortex and striatum after PBS treatment compared to LIF treatment. MCAO + LIF significantly decreased splenic levels of CD11b and CD3 compared to sham surgery. MCAO + PBS treatment significantly elevated splenic levels of interferon inducible protein-10 at 72 h after MCAO, while LIF treatment after MCAO returned interferon inducible protein 10 to sham levels. LIF administration with interferon gamma + LPS significantly reduced the IL-12/IL-10 production ratio compared to macrophages treated with interferon gamma + LPS alone. CONCLUSIONS: These data demonstrate that LIF promotes anti-inflammatory signaling through alterations of the IL-12/interferon gamma/interferon inducible protein 10 pathway.

Circumcision status at HIV infection is not associated with plasma viral load in men: analysis of specimens from a randomized controlled trial.

BACKGROUND: Male circumcision provides men with approximately 60% protection from acquiring HIV infection via heterosexual sex, and has become a key component of HIV prevention efforts in sub-Saharan Africa. Possible mechanisms for this protection include removal of the inflammatory anaerobic sub-preputial environment and the high concentration of Langerhans cells on the inside of the foreskin, both believed to promote local vulnerability to HIV infection. In people who do acquire HIV, viral load is partially determined by infecting partner viral load, potentially mediated by size of infecting inoculum. By removing a portal for virion entry, prior male circumcision could decrease infecting inoculum and thus viral load in men who become HIV-infected, conferring the known associated benefits of slower progression to disease and decreased infectiousness. METHODS: We performed an as-treated analysis of plasma samples collected under a randomized controlled trial of male circumcision for HIV prevention, comparing men based on their circumcision status at the time of HIV acquisition, to determine whether circumcision is associated with lower viral load. Eligible men were seroconverters who had at least one plasma sample available drawn at least 6 months after infection, reported no potential exposures other than vaginal sex and, for those who were circumcised, were infected more than 6 weeks after circumcision, to eliminate the open wound as a confounder. Initial viral load testing indicated that quality of pre-2007 samples might have been compromised during storage and they were excluded, as were those with undetectable or unquantifiable results. Log viral loads were compared between groups using univariable and multivariable linear regression, adjusting for sample age and sexually transmitted infection diagnosis with 3.5 months of seroconversion, with a random effect for intra-individual clustering for samples from the same man. A per-protocol analysis was also performed. RESULTS: There were no viral load differences between men who were circumcised and uncircumcised at the time of HIV infection (means 4.00 and 4.03 log10 copies/mL respectively, p = .88) in any analysis. CONCLUSION: Circumcision status at the time of HIV infection does not affect viral load in men. TRIAL REGISTRATION: The original RCT which provided the samples was ClinicalTrials.gov trial NCT00059371 .

Leukemia Inhibitory Factor-Loaded Nanoparticles with Enhanced Cytokine Metabolic Stability and Anti-Inflammatory Activity.

PURPOSE: To synthesize and assess the in vitro biological activity of nanoparticles containing leukemia inhibitory factor (LIF). These NanoLIF particles are designed to prolong the neuroprotective and anti-inflammatory actions of LIF in future preclinical studies of ischemic stroke. METHODS: LIF was packaged in nanoparticles made of poly(ethylene glycol)-poly(lactic acid) (PEG-PLA) polymer to form LIF-loaded nanoparticles (NanoLIF). The surface of NanoLIF was also modified with the CD11b antibody (CD11b-NanoLIF) targeting activated peripheral macrophages to increase cytokine delivery to inflammatory macrophages. ELISA was used to quantify bioactive cytokine inside and releasing from NanoLIF. NanoLIF biological activity was measured using the M1 murine leukemia cell proliferation assay. RESULTS: NanoLIF and CD11b-NanoLIF had diameters of approximately 30 nm, neutral surface charge, and physicochemical stability retaining biological activity of the cytokine during incubation at 25°C for 12 h. NanoLIF particles released LIF relatively fast from 0 to 6 h after incubation at 37°C followed by slow release from 24 to 72 h according to a two-phase exponential decay model. NanoLIF and CD11b-NanoLIF significantly decreased M1 cell proliferation over 72 h compared to free LIF. CONCLUSIONS: NanoLIF and CD11b-NanoLIF preserved the metabolic stability and biological activity of LIF in vitro. These results are promising to improve the therapeutic potential of LIF in treating neurodegenerative and inflammatory diseases.

The role of the leukemia inhibitory factor receptor in neuroprotective signaling.

Several neurotropic cytokines relay their signaling through the leukemia inhibitory factor receptor. This 190kDa subunit couples with the 130kDa gp130 subunit to transduce intracellular signaling in neurons and oligodendrocytes that leads to expression of genes associated with neurosurvival. Moreover, activation of this receptor alters the phenotype of immune cells to an anti-inflammatory one. Although cytokines that activate the leukemia inhibitory factor receptor have been studied in the context of neurodegenerative disease, therapeutic targeting of the specific receptor subunit has been understudied in by comparison. This review examines the role of this receptor in the CNS and immune system, and its application in the treatment in stroke and other brain pathologies.

Association between male circumcision and women's biomedical health outcomes: a systematic review.

BACKGROUND: Male circumcision reduces men's risk of acquiring HIV and some sexually transmitted infections from heterosexual exposure, and is essential for HIV prevention in sub-Saharan Africa. Studies have also investigated associations between male circumcision and risk of acquisition of HIV and sexually transmitted infections in women. We aimed to review all evidence on associations between male circumcision and women's health outcomes to benefit women's health programmes. METHODS: In this systematic review we searched for peer-reviewed and grey literature publications reporting associations between male circumcision and women's health outcomes up to April 11, 2016. All biomedical (not psychological or social) outcomes in all study types were included. Searches were not restricted by year of publication, or to sub-Saharan Africa. Publications without primary data and not in English were excluded. We extracted data and assessed evidence on each outcome as high, medium, or low consistency on the basis of agreement between publications; outcomes found in fewer than three publications were indeterminate consistency. FINDINGS: 60 publications were included in our assessment. High-consistency evidence was found for five outcomes, with male circumcision protecting against cervical cancer, cervical dysplasia, herpes simplex virus type 2, chlamydia, and syphilis. Medium-consistency evidence was found for male circumcision protecting against human papillomavirus and low-risk human papillomavirus. Although the evidence shows a protective association with HIV, it was categorised as low consistency, because one trial showed an increased risk to female partners of HIV-infected men resuming sex early after male circumcision. Seven outcomes including HIV had low-consistency evidence and six were indeterminate. INTERPRETATION: Scale-up of male circumcision in sub-Saharan Africa has public health implications for several outcomes in women. Evidence that female partners are at decreased risk of several diseases is highly consistent. Synergies between male circumcision and women's health programmes should be explored. FUNDING: US Centers for Disease Control and Prevention and Jhpiego.

Targeting antioxidant enzyme expression as a therapeutic strategy for ischemic stroke.

During ischemic stroke, neurons and glia are subjected to damage during the acute and neuroinflammatory phases of injury. Production of reactive oxygen species (ROS) from calcium dysregulation in neural cells and the invasion of activated immune cells are responsible for stroke-induced neurodegeneration. Scientists have failed thus far to identify antioxidant-based drugs that can enhance neural cell survival and improve recovery after stroke. However, several groups have demonstrated success in protecting against stroke by increasing expression of antioxidant enzymes in neural cells. These enzymes, which include but are not limited to enzymes in the glutathione peroxidase, catalase, and superoxide dismutase families, degrade ROS that otherwise damage cellular components such as DNA, proteins, and lipids. Several groups have identified cellular therapies including neural stem cells and human umbilical cord blood cells, which exert neuroprotective and oligoprotective effects through the release of pro-survival factors that activate PI3K/Akt signaling to upregulation of antioxidant enzymes. Other studies demonstrate that treatment with soluble factors released by these cells yield similar changes in enzyme expression after stroke. Treatment with the cytokine leukemia inhibitory factor increases the expression of peroxiredoxin IV and metallothionein III in glia and boosts expression of superoxide dismutase 3 in neurons. Through cell-specific upregulation of these enzymes, LIF and other Akt-inducing factors have the potential to protect multiple cell types against damage from ROS during the early and late phases of ischemic damage.

Leukemia Inhibitory Factor Protects Neurons from Ischemic Damage via Upregulation of Superoxide Dismutase 3.

Leukemia inhibitory factor (LIF) has been shown to protect oligodendrocytes from ischemia by upregulating endogenous antioxidants. The goal of this study was to determine whether LIF protects neurons during stroke by upregulating superoxide dismutase 3 (SOD3). Animals were administered phosphate-buffered saline (PBS) or 125 µg/kg LIF at 6, 24, and 48 h after middle cerebral artery occlusion or sham surgery. Neurons were isolated from rat pups on embryonic day 18 and used between 7 and 15 days in culture. Cells were treated with LIF and/or 10 µM Akt inhibitor IV with PBS and 0.1 % DMSO acting as vehicle controls. Neurons transfected with scrambled or SOD3 small interfering RNA (siRNA) were subjected to 24-h ischemia after PBS or LIF treatment. LIF significantly increased superoxide dismutase activity and SOD3 expression in ipsilateral brain tissue compared to PBS. Following 24-h ischemia, LIF reduced cell death and increased SOD3 messenger RNA (mRNA) in vitro compared to PBS. Adding Akt inhibitor IV with LIF counteracted the decrease in cell death. Partially silencing the expression of SOD3 using siRNA prior to LIF treatment counteracted the protective effect of LIF-alone PBS treatment. These results indicate that LIF protects neurons in vivo and in vitro via upregulation of SOD3.

Morbidity associated with schistosomiasis before and after treatment in young children in Rusinga Island, western Kenya.

Schistosoma mansoni infection is a major cause of organomegaly and ultimately liver fibrosis in adults. Morbidity in pre-school-aged children is less defined, and they are currently not included in mass drug administration (MDA) programs for schistosomiasis control. We report results of a study of the association of schistosomiasis with organomegaly in a convenience sample of 201 children under 7 years old in Rusinga, Kenya on two cross-sectional visits, before and after praziquantel treatment. Data included stool examination and serology for schistosomiasis, the Niamey ultrasound protocol to stage hepatosplenic morbidity including organomegaly, and potential confounders including malaria. Unadjusted and adjusted Poisson regressions were performed. The baseline prevalence of schistosomiasis by antibody and/or stool was 80.3%. Schistomiasis was associated with hepatomegaly (adjusted prevalence ratio [aPR] = 1.4; 95% confidence interval [CI]: 1.0-2.1) and splenomegaly (aPR = 2.1; 95% CI: 1.2-3.7). The association with hepatomegaly persisted posttreatment (aPR = 1.4; 95% CI: 1.1-1.6). Schistosomiasis was associated with morbidity in this cohort. Efforts to include young children in mass treatment campaigns should intensify.

Regurgitant valvular disease prevalence and progression found on echocardiogram in military aviators.

INTRODUCTION: The prevalence, progression rates, and outcomes affecting aviator valvular heart disease have not been extensively studied. METHODS: The U.S. Air Force (USAF) School of Aerospace Medicine's Clinical Sciences Database was used to determine prevalence and progression rates for regurgitant valvular disease. A subset of the initial population was further evaluated for risk factors that increased the likelihood of progression. Descriptive statistical analysis, analysis of variance, and t-test calculations were completed. RESULTS: There were 8475 unique aviators with some degree of valvular regurgitation for an overall prevalence of 3.0%. The mitral and aortic valves were most likely to have mild and moderate or greater regurgitation, respectively. Progression rates from mild to moderate were 8% in the aortic valve, 2% in the mitral valve, and less than 1% in the pulmonic and tricuspid valves. Progression rates from moderate to severe were over 20% for both the mitral and aortic valves. The only risk factors correlating to progression of valvular disease were lower levels of high-density lipoproteins in the mitral and aortic valves and triglycerides in the mitral valve. DISCUSSION: In USAF aviators, progression rates for mild or greater aortic valve regurgitation and moderate or greater mitral valve regurgitation are significant and should be followed closely. Classic risk factors of age, tobacco use, elevated blood pressure, and hyperlipidemia have no association with increased risk of valvular progression or rate of progression. Study outcomes validate the current USAF policy for valvular heart disease in aviators.

Non-muscle Mlck is required for ß-catenin- and FoxO1-dependent downregulation of Cldn5 in IL-1ß-mediated barrier dysfunction in brain endothelial cells.

Aberrant elevation in the levels of the pro-inflammatory cytokine interleukin-1ß (IL-1ß) contributes to neuroinflammatory diseases. Blood-brain barrier (BBB) dysfunction is a hallmark phenotype of neuroinflammation. It is known that IL-1ß directly induces BBB hyperpermeability but the mechanisms remain unclear. Claudin-5 (Cldn5) is a tight junction protein found at endothelial cell-cell contacts that are crucial for maintaining brain microvascular endothelial cell (BMVEC) integrity. Transcriptional regulation of Cldn5 has been attributed to the transcription factors ß-catenin and forkhead box protein O1 (FoxO1), and the signaling molecules regulating their nuclear translocation. Non-muscle myosin light chain kinase (nmMlck, encoded by the Mylk gene) is a key regulator involved in endothelial hyperpermeability, and IL-1ß has been shown to mediate nmMlck-dependent barrier dysfunction in epithelia. Considering these factors, we tested the hypothesis that nmMlck modulates IL-1ß-mediated downregulation of Cldn5 in BMVECs in a manner that depends on transcriptional repression mediated by ß-catenin and FoxO1. We found that treating BMVECs with IL-1ß induced barrier dysfunction concomitantly with the nuclear translocation of ß-catenin and FoxO1 and the repression of Cldn5. Most importantly, using primary BMVECs isolated from mice null for nmMlck, we identified that Cldn5 repression caused by ß-catenin and FoxO1 in IL-1ß-mediated barrier dysfunction was dependent on nmMlck.