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Background-: Glaucoma is a complex multifactorial disease where apoptosis and inflammation represent two key pathogenic mechanisms. However, the relative contribution of apoptosis versus inflammation in axon degeneration and death of retinal ganglion cells (RGCs) is not well understood. In glaucoma, caspase-8 is linked to RGC apoptosis, as well as glial activation and neuroinflammation. To uncouple these two pathways and determine the extent to which caspase-8-mediated inflammation and/or apoptosis contributes to the death of RGCs, we used the caspase-8 D387A mutant mouse (Casp8 ^DA/DA ) in which a point mutation in the auto-cleavage site blocks caspase-8-mediated apoptosis but does not block caspase-8-mediated inflammation.

Methods-: Intracameral injection of magnetic microbeads was used to elevate the intraocular pressure (IOP) in wild-type, Fas deficient Fas^lpr, and Casp8 ^DA/DA mice. IOP was monitored by rebound tonometry. Two weeks post microbead injection, retinas were collected for microglia activation analysis. Five weeks post microbead injection, visual acuity and RGC function were assessed by optometer reflex (OMR) and pattern electroretinogram (pERG), respectively. Retina and optic nerves were processed for RGC and axon quantification. Two- and five-weeks post microbead injection, expression of the necrosis marker, RIPK3, was assessed by qPCR.

Results-: Wild-type, Fas^lpr, and Casp8 ^DA/DA mice showed similar IOP elevation as compared to saline controls. A significant reduction in both visual acuity and pERG that correlated with a significant loss of RGCs and axons was observed in wild-type but not in Fas^lpr mice. The Casp8 ^DA/DA mice displayed a significant reduction in visual acuity and pERG amplitude and loss of RGCs and axons similar to that in wild-type mice. Immunostaining revealed equal numbers of activated microglia, double positive for P2ry12 and IB4, in the retinas from microbead-injected wild-type and Casp8 ^DA/DA mutant mice. qPCR analysis revealed no induction of RIPK3 in wild-type or Casp8 ^DA/DA mice at two- or five-weeks post microbead injection.

Conclusions-: Our results demonstrate that caspase-8-mediated extrinsic apoptosis is not involved in the death of RGCs in the microbead-induced mouse model of glaucoma implicating caspase-8-mediated inflammation, but not apoptosis, as the driving force in glaucoma progression. Taken together, these results identify the caspase-8-mediated inflammatory pathway as a potential target for neuroprotection in glaucoma.

Background: Transnational drug trafficking, political unrest, gang violence, and paramilitarism, which are pervasive in Haiti, have resulted in a mental health crisis for the broader Haitian community. This study explores the mental well-being of Haitians in Haiti and the United States by identifying barriers and facilitators to mental health through the lived experiences of men and women.

Method: Four Focus group discussions conducted in April and November 2023 engaged 28 participants (20 women and eight men) aged between 23 and 60 years from locations in Haiti (Port-au-Prince, Cite Soleil, Cayes, Cap-Haitien, Saint-Marc) and the United States. Discussions revolved around the definition of mental health, stressors, coping mechanisms, risk and protective factors, and barriers to mental health care.

Results: Six principal themes emerged: 1- Chronic Traumatic Stress: continued violence, political instability, unemployment, lack of social support, adverse childhood experiences, family separation, and forced displacement were significant sources of stress. 2- Increased Health Burden: Participants reported experiencing chronic physical and psychological symptoms (i.e., hypertension, anxiety, depression, sleep issues, substance abuse, suicidal ideations, characteristics of post-traumatic stress disorder [PTSD]), which were attributed to Haiti's social, political, and infrastructure collapse. 3- Risk Factors: limited access to mental health services, pervasive hopelessness, scarcity of opportunities, and stigma were identified as significant risks. 4- Future Uncertainty: widespread concerns regarding the future predominated. 5- Multigenerational Concerns: Significant anxiety concerning the mental health and development of children, as well as the functionality of mental health practitioners, was noted. 6- Coping and Protective Factors: Effective coping strategies include mental stimulation, peer support, managing digital consumption, engaging in leisurely activities, such as listening to music, and faith/spirituality.

Conclusion: The study's findings underscore the sociopolitical and economic crisis in Haiti, which has resulted in violence and a collapse of political, educational, financial, and health infrastructures. These factors were identified as the primary source of chronic distress, contributing to widespread mental health issues, adverse physical symptoms, and disruption in daily life. The implications for practice, healing, research & policy are discussed.

Background: Effective interventions for metabolic liver disease include optimized nutritional intake. It is increasingly clear, however, that many patients with metabolic liver disease lack the resources to execute nutritional advice. Data on the trends of food insecurity are needed to prioritize public health strategies to address the burden of liver disease.

Methods: Cross-sectional analysis of six waves of data from the 2007-2018, 24,847 subjects aged ≥20 years from the 2017-2018 National Health and Nutrition Examination Survey. Food security was measured using the US Department of Agriculture's Core Food Security Module. Liver disease was defined as elevated liver enzymes and a risk factor: elevated BMI, diabetes, and/or excess alcohol consumption. Models were adjusted using age, sex, race/ethnicity, education, poverty-income ratio, smoking, physical activity, alcohol intake, sugary beverage intake, Healthy Eating Inex-2015 score. Advanced liver disease was estimated using FIB-4 >2.67.

Results: The overall prevalence of liver disease was 24.6%, ranging from 21.1% (2017-2018) to 28.3% (2015-2016) (P-trend=0.85). 3.4% of participants had possible advanced liver disease, ranging from 1.9% (2007-2008) to 4.2% (2015-2016)(P-trend=0.07). Among those with liver disease, the prevalence of food insecurity was 13.6% in 2007-2008, which rose steadily to 21.6% in 2015-2016, before declining to 18.0% in 2017-2018 (P-trend=0.0004). Food insecurity rose more sharply for adults aged <50 years (2007-2008: 17.6%, 2015-2016: 28.0%, P-trend=0.004) compared to adults aged ≥50 years (2007-2008: 9.5%, 2015-2016: 16.5%, P-trend<0.0001). Food insecurity was more common among women, those with high BMI, and those with diabetes.

Conclusion: Food insecurity is increasingly common among those with liver disease.

Purpose: Spontaneously occurring glioma in pet dogs is increasingly recognized as a valuable translational model for human glioblastoma. Canine high grade glioma and human glioblastomas share many molecular similarities, including accumulation of immunosuppressive regulatory T cells (Tregs) that inhibit anti-tumor immune responses. Identifying in dog mechanisms responsible for Treg recruitment may afford targeting the cellular population driving immunosuppression, the results providing a rationale for translational clinical studies in human patients. Our group has previously identified C-C motif chemokine 2 (CCL2) as a glioma-derived T-reg chemoattractant acting on chemokine receptor 4 (CCR4) in a murine orthotopic model of glioma. Recently, we demonstrated a robust increase of CCL2 in the brain tissue of canine patients bearing high-grade glioma.

Methods: We performed a series of in vitro experiments using canine Tregs and patient-derived canine glioma cell lines (GSC 1110, GSC 0514, J3T-Bg, G06A) to interrogate the CCL2-CCR4 signaling axis in the canine.

Results: We established a flow cytometry gating strategy for identification and isolation of FOXP3⁺ Tregs in dogs. The canine CD4 + CD25^high T-cell population was highly enriched in FOXP3 and CCR4 expression, indicating they are bona fide Tregs. Canine Treg migration was enhanced by CCL2 or by glioma cell line-derived supernatant. Blockade of the CCL2-CCR4 axis significantly reduced migration of canine Tregs. CCL2 mRNA was expressed in all glioma cell lines and expression increased when exposed to Tregs but not to CD4 + helper T-cells.

Conclusion: Our study validates CCL2-CCR4 as a bi-directional Treg-glioma immunosuppressive and tumor-promoting axis in canine high-grade glioma.

Organoid cultures offer a powerful technology to investigate many different aspects of development, physiology, and pathology of diverse tissues. Unlike standard tissue culture of primary breast epithelial cells, breast organoids preserve the epithelial lineages and architecture of the normal tissue. However, existing organoid culture methods are tedious, difficult to scale, and do not robustly retain estrogen receptor (ER) expression and responsiveness in long-term culture. Here, we describe a modified culture method to generate and maintain organoids as suspension cultures in reconstituted basement membrane (^™Matrigel). This method improves organoid growth and uniformity compared to the conventional Matrigel dome embedding method, while maintaining the fidelity of the three major epithelial lineages. Using this adopted method, we are able to culture and passage purified hormone sensing (HS) cells that retain ER responsiveness upon estrogen stimulation in long-term culture. This culture system presents a valuable platform to study the events involved in initiation and evolution of ER-positive breast cancer.

Objective: Evaluate the changes in management and outcomes of Californian infants with hypoxic ischemic encephalopathy (HIE).

Study design: Infants with HIE were identified from a California administrative birth cohort using ICD codes and divided into two epochs, Epoch 1 (2010-2015) and Epoch 2 (2016-2019). Risk ratios (RR) for therapeutic hypothermia (TH) in each epoch and their outcomes were calculated using log-linear regression.

Results: In this cohort, 4779 infants with HIE were identified. Incidence of HIE in California increased yearly from 0.5/1,000 California births to a peak of 1.5/1,000 births in 2018. The use of TH in infants with mild HIE increased in Epoch 2 compared to Epoch 1. There was no significant difference in outcomes between epochs for infants with mild HIE that received TH.

Conclusion: Significantly more infants with mild HIE received TH since 2015 in California, but no difference in outcomes was found for these patients.

Inhibition of translation initiation using eIF4A inhibitors like (-)-didesmethylrocaglamide [(-)-DDR] and (-)-rocaglamide [(-)-Roc] is a potential cancer treatment strategy as they simultaneously diminish multiple oncogenic drivers. We showed that human and dog osteosarcoma cells expressed high levels of eIF4A1/2, particularly eIF4A2. Genetic depletion of eIF4A1 and/or 2 slowed osteosarcoma cell growth. To advance preclinical development of eIF4A inhibitors, we demonstrated the importance of (-)-chirality in DDR for growth-inhibitory activity. Bromination of DDR at carbon-5 abolished growth-inhibitory activity, while acetylating DDR at carbon-1 was tolerated. Like DDR and Roc, DDR-acetate increased the γH2A.X levels and induced G₂/M arrest and apoptosis. Consistent with translation inhibition, these rocaglates decreased the levels of several mitogenic kinases, the STAT3 transcription factor, and the stress-activated protein kinase p38. However, phosphorylated p38 was greatly enhanced in treated cells, suggesting activation of stress response pathways. RNA sequencing identified RHOB as a top upregulated gene in both DDR- and Roc-treated osteosarcoma cells, but the Rho inhibitor Rhosin did not enhance the growth-inhibitory activity of (-)-DDR or (-)-Roc. Nonetheless, these rocaglates potently suppressed tumor growth in a canine osteosarcoma patient-derived xenograft model. These results suggest that these eIF4A inhibitors can be leveraged to treat both human and dog osteosarcomas.

Wolbachia is an obligate intracellular α-proteobacterium which commonly infects arthropods and filarial nematodes. Different strains of Wolbachia are capable of a wide range of regulatory manipulations in many hosts and modulate host cellular differentiation to influence host reproduction. The genetic basis for the majority of these phenotypes is unknown. The wWil strain from the neotropical fruit fly, Drosophila willistoni, exhibits a remarkably high affinity for host germline-derived cells relative to the soma. This trait could be leveraged for understanding how Wolbachia influences the host germline and for controlling host populations in the field. To further the use of this strain in biological and biomedical research, we sequenced the genome of the wWil strain isolated from host cell culture cells. Here, we present the first high quality nanopore assembly of wWil, the Wolbachia endosymbiont of D. willistoni. Our assembly resulted in a circular genome of 1.27 Mb with a BUSCO completeness score of 99.7%. Consistent with other insect-associated Wolbachia strains, comparative genomic analysis revealed that wWil has a highly mosaic genome relative to the closely related wMel strain from Drosophila melanogaster.

Fragile X syndrome (FXS) is a rare neurodevelopmental disorder caused by a CGG repeat expansion ≥ 200 repeats in 5' untranslated region of the FMR1 gene, leading to intellectual disability and cognitive difficulties, including in the domain of communication. A recent phase 2a clinical trial testing BPN14770, a phosphodiesterase 4D inhibitor, showed improved cognition in 30 adult males with FXS on drug relative to placebo. The initial study found significant improvements in clinical measures assessing cognition, language, and daily functioning in addition to marginal improvements in electroencephalography (EEG) results for the amplitude of the N1 event-related potential (ERP) component. EEG results suggest BPN14770 improved neural hyperexcitability in FXS. The current study investigated the relationship between BPN14770 pharmacokinetics (PK) and the amplitude of the N1 ERP component from the initial data. Consistent with the original group-level finding in period 1 of the study, participants who received BPN14770 in the period 1 showed a significant correlation between N1 amplitude and serum concentration of BPN14770. These findings strengthen the validity of the original result, indicating that BPN14770 improves cognitive performance by modulating neural hyperexcitability. This study represents the first report of significant correlation between a reliably abnormal EEG marker and serum concentration of a novel pharmaceutical in FXS.

Background: Rising hepatitis C and B virus (HCV and HBV) rates have been reported in men who have sex with men (MSM) and transgender women (TGW). This study characterizes HCV and HBV infections longitudinally among 2,496 MSM/TGW aged 18-50 years and at risk for HIV acquisition enrolled in an HIV-1 vaccine trial in 18 U.S. cities between 2009-2013.

Methods: Participants completed behavioral surveys, HIV testing, and blood collection over 24 months. Of the 2,397 participants who consented for future testing, 1,792 (74.8%) had available paired stored blood samples at baseline and a later timepoint (Month 24 [N = 999]; if unavailable, M12 [N = 775] or M15 [N = 18]).

Results: Among 1,792 participants, 98.1% were MSM, 0.8% were TGW, and the median age was 30 years (IQR 24, 40). Participants reported a median number of 3 male sex partners (IQR 1,5) within the past 3 months. Condomless insertive anal sex was reported by 55.8% and condomless receptive anal sex by 46.7%.1.3% reported injection drug use. During follow-up, 1.4% reported pre-exposure prophylaxis (PrEP) use. At baseline 11/1792 (0.61%) participants had HCV infection (HCV AB positive, RNA detectable), with all having persistent detectable RNA and chronic HCV infection at follow-up. Phylogenetic analysis showed no clusters of HCV infection. 8 participants had HCV AB positive, RNA undetectable at baseline and follow-up, representing past HCV infection with clearance; only 2 acquired HCV, which cleared over 12-24 months. At baseline, 2 participants (2/1792 = 0.11%) had positive HBsAg, indicating chronic HBV infection. Over 12-24 months, 4 (4/1790, 0.22%) developed HBsAg positivity; these participants had HBcAB positivity at baseline, thereby likely representing reactivation. There were no new HBV infections during follow-up.

Conclusion: Among 1,792 men who have sex with men and transgender women aged 18-50 years and at risk for HIV acquisition enrolled in a U.S. HIV-1 vaccine trial, incident hepatitis C infection rates were extremely low, with no cases of incident hepatitis B infection. These rates of incident HCV infection and HBSAg positivity are lower than previously reported among MSM/TGW.