Targeted nanotherapeutics for the treatment of Helicobacter pylori infection.

Helicobacter pylori infection is involved in gastric diseases such as peptic ulcer and adenocarcinoma. Approved antibiotherapies still fail in 10 to 40% of the infected patients and, in this scenario, targeted nanotherapeutics emerged as powerful allies for H. pylori eradication. Nano/microparticles conjugated with H. pylori binding molecules were developed to eliminate H. pylori by either (i) blocking essential mechanisms of infection, such as adhesion to gastric mucosa or (ii) binding and killing H. pylori through the release of drugs within the bacteria or at the site of infection. Glycan antigens (as Lewis B and sialyl-Lewis X), pectins, lectins, phosphatidylethanolamine and epithelial cell membranes were conjugated with nano/microparticles to successfully block H. pylori adhesion. Urea-coated nanoparticles were used to improve drug delivery inside bacteria through H. pylori UreI channel. Moreover, nanoparticles coated with antibodies against H. pylori and loaded with sono/photosensitizers, were promising for their application as targeted sono/photodynamic therapies. Further, non-specific H. pylori nano/microparticles, but only active in the acidic gastric environment, coated with binders to bacterial membrane, extracellular polymeric substances or to high temperature requirement A protease, were evaluated. In this review, an overview of the existing nanotherapeutics targeting H. pylori will be given and their rational, potential to counteract infection, as well as level of development will be presented and discussed.

Endothelial c-Myc knockout disrupts metabolic homeostasis and triggers the development of obesity.

Introduction: Obesity is a major risk factor associated with multiple pathological conditions including diabetes and cardiovascular disease. Endothelial dysfunction is an early predictor of obesity. However, little is known regarding how early endothelial changes trigger obesity. In the present work we report a novel endothelial-mediated mechanism essential for regulation of metabolic homeostasis, driven by c-Myc. Methods: We used conditional knockout (EC-Myc KO) and overexpression (EC-Myc OE) mouse models to investigate the endothelial-specific role of c-Myc in metabolic homeostasis during aging and high-fat diet exposure. Body weight and metabolic parameters were collected over time and tissue samples collected at endpoint for biochemical, pathology and RNA-sequencing analysis. Animals exposed to high-fat diet were also evaluated for cardiac dysfunction. Results: In the present study we demonstrate that EC-Myc KO triggers endothelial dysfunction, which precedes progressive increase in body weight during aging, under normal dietary conditions. At endpoint, EC-Myc KO animals showed significant increase in white adipose tissue mass relative to control littermates, which was associated with sex-specific changes in whole body metabolism and increase in systemic leptin. Overexpression of endothelial c-Myc attenuated diet-induced obesity and visceral fat accumulation and prevented the development of glucose intolerance and cardiac dysfunction. Transcriptome analysis of skeletal muscle suggests that the protective effects promoted by endothelial c-Myc overexpression are associated with the expression of genes known to increase weight loss, energy expenditure and glucose tolerance. Conclusion: Our results show a novel important role for endothelial c-Myc in regulating metabolic homeostasis and suggests its potential targeting in preventing obesity and associated complications such as diabetes type-2 and cardiovascular dysfunction.

Field study to determine the reliability of HIV viral load results shows minimal impact of delayed testing in South Africa.

Background: Understanding factors that impact HIV viral load (VL) accuracy in resource-limited settings is key to quality improvement. Objective: We evaluated whether testing delay and specimen storage between 25 °C and 30 °C before testing affected results. Methods: Between November 2019 and June 2023, 249 individuals on antiretroviral therapy, or with newly diagnosed HIV, were recruited from clinics in Cape Town and Gqeberha, South Africa, and three plasma preparation tubes were collected. One tube was tested within 24 h, while the others were stored uncentrifuged at ambient temperatures before testing. Centrifugation and testing of matched samples were performed on Day 4 and Day 7 after collection. Results: Time delay and ambient storage had minimal impact in specimens with a Day 1 VL of > 100 copies/mL. When grouped by Day 1 VL range, 96% - 100% of specimens at Day 4 and 93% - 100% at Day 7 had VLs within 0.5 log copies/mL of the first result. The greatest variability at Days 4 and 7 was observed when the Day 1 VL was < 100 copies/mL. However, there was no trend of increasing difference over time. Of Day 1 specimens with undetectable VL, or VL < 50 copies/mL, 80% had concordant results at Day 4 and 78% at Day 7. Conclusion: These results show that VL is stable in plasma preparation tubes for 7 days when stored at room temperature. There is significant variability in specimens with low VL, but variability is not affected by testing delay. What this study adds: Ideal HIV VL testing conditions are frequently unachievable in resource-limited settings. Data are needed on whether this impacts on the validity of test results. Our results provide reassurance that storage at ambient temperature for up to 7 days before testing does not substantially affect the VL result.

Description of Post-discharge Outcomes of Patients with COVID-19 in a Tertiary Referral Center in the Philippines.

Background and Objectives: The immediate post-discharge period of COVID-19 patients is a vulnerable state due to several complications that may arise during this time. Some patients get readmitted shortly after being discharged while others report persistence of symptoms, develop specialized needs, or observe a decline from their baseline functional capacity. Information on the outcomes of post-COVID discharge patients in our institution is currently lacking. This study described the outcomes of patients with COVID-19 after their discharge from the service areas of Philippine General Hospital. Methods: This study is a retrospective chart review involving charts of all adult patients discharged from the PGH COVID service areas last August 2021 to October 2021. Data from their follow up consults at 1 week, 1 month, and 3 months post-discharge were reviewed. Baseline characteristics and post-discharge outcomes including post-COVID symptoms, special care needs, mortality, rehospitalization, emergency consult, level of dependence, and ability to return to work were assessed. Results: A total of 171 patient charts were included. The mean age of patients was 53.7 years. Most were male (60.2%), unemployed (59.7%), non-smoker (55%), hypertensive (57.9%), diabetic (50.2%), and obese (50.2%). Most of them were oxygen requiring (80%) and with severe to critical COVID infection (72.5%) during admission. At 3 months post-discharge, 113 (66%) were stable and able to complete the follow up, 8 (4.6%) died, 9 (5.2%) got readmitted, and 41 (23.9%) were lost to follow up. Among those who were able to follow up after 3 months, 84 (74%) were asymptomatic. Among those who remained symptomatic, the most common symptoms were dyspnea, fatigue, and cough. After 3 months, 100 (88%) did not require special care needs, 100 (88%) were fully independent, and 45 (39.8%) were able to return to baseline work. Conclusions: Despite the majority of patients having severe to critical COVID infection during admission, most were asymptomatic within 3 months post-discharge. In those who developed persistent symptoms, dyspnea, cough, and fatigue were the most common symptoms identified regardless of COVID severity. Majority did not require special care needs.

Description of Core Performance Measures and Indicators of Patient Safety Used by Select Government and Private Hospitals in the Philippines.

Background: In 2008, the Department of Health (DOH) issued Administrative Order 2008-0023 that called for an "effective and efficient monitoring system that will link all patient safety initiatives". However, there are still no explicit and harmonized targets to measure effectiveness and to provide benchmarks that assess whether previous efforts were helpful. Objective: The study aimed to describe the status of patient safety performance measures and indicators on the international patient safety goals (IPSGs) in select hospitals in the Philippines. Methods: Descriptive, cross-sectional design was used to investigate currently used performance measures and indicators. Data collection included administration of a Hospital Patient Safety Indicators Questionnaire (HPSIQ) that summarized the currently used patient safety measures and indicators in the sampled Level 2 and level 3 hospitals and triangulation by review of documents such as hospital databases, protocols on reporting, and manuals for information gathering regarding patient safety. Performance measures were categorized using the Donabedian framework. Core indicators were identified through review of standards that cut across the six IPSGs and evaluation of overarching processes and concepts in patient safety. Results: Forty-one level 2 and 3 hospitals participated in the study. Most performance indicators were process measures (52%), while structure (31%) and outcome measures (17%) accounted for the rest. There is an obvious lack of structural requirements for patient safety in the hospitals included in this study. Less than half the hospitals surveyed implement risk assessment and management consistently. Reporting of events, near-misses, and patient safety data are widely varied among hospitals. Data utilization for quality improvement is not fully established in many of the hospitals. Patient engagement is not integrated in service delivery and performance measurement but is crucial in promoting patient safety. Conclusion: Mechanisms to improve hospitals' capacity to monitor, anticipate, and reduce risk of patient harm during the provision of healthcare should be provided. Having a unified set of definitions and protocols for measurement will facilitate reliable monitoring and improvement. Leadership and governance, both internal (e.g., hospital administrators) and external (e.g., DOH) that recognize a data-driven approach to policymaking and improvement of service delivery are crucial in promoting patient safety.

Potassium-Based Sodium Substitutes Impact the Sodium and Potassium Content of Foods.

OBJECTIVE: Potassium-based sodium substitutes (PBSS) can be used to replace sodium during food processing. How potassium and sodium content is associated with PBSS is not known. The objectives of the study were to describe the prevalence of PBSS by sodium content claim category and describe how PBSS are associated with sodium and potassium concentrations by sodium level. DESIGN AND METHODS: This cross-sectional analysis used the July 2018 version of the United States Department of Agriculture's Branded Food Products Database. Products were divided into sodium content claim category and were analyzed for the presence of PBSS. Products with nonmissing values for sodium and potassium were grouped by sodium level and analyzed for the prevalence of PBSS to explore potassium and sodium concentration. Column proportion z-test with the Bonferroni correction was used to explore the occurrence of PBSS by sodium content claim category. Mann-Whitney U-test was used to assess differences in potassium and sodium concentrations across sodium levels and within levels by the presence/absence of PBSS. RESULTS: The prevalence of PBSS in the categories "without a sodium content claim" (2.4%), "lightly salted" (0.5%), and "unsalted" claims (0.6%) were statistically significantly lower than prevalence of PBSS in the "sodium free" (9.5%), "low sodium" (10.3%), and "reduced sodium" claim categories (23.3%; all P < .01). Among the group of products with serving sizes more than 30 g containing PBSS, there was a 357 mg per serving higher median sodium concentration and a 160 mg per serving higher median potassium concentration compared to the group without PBSS (both P < .01). CONCLUSION: In the "reduced sodium" claim category, a higher prevalence of PBSS was found compared to other sodium claim categories. The presence of PBSS was associated with higher potassium and sodium concentrations in foods.

The Low-Waste Grafting Copolymerization Modification of Chitosan Is a Promising Approach to Obtaining Materials for Food Applications.

Chitosan takes second place of the most abundant polysaccharides naturally produced by living organisms. Due to its abundance and unique properties, such as its polycationic nature, ability to form strong elastic porous films, and antibacterial potential, it is widely used in the food industry and biomedicine. However, its low solubility in both water and organic solvents makes its application difficult. We have developed an environmentally friendly method for producing water-soluble graft copolymers of chitosan and poly (N-vinylpyrrolidone) with high grafting efficiency and a low yield of by-products. By using AFM, SEM, TGA, DSC, and XRD, it has been demonstrated that the products obtained have changed properties compared to the initial chitosan. They possess a smoother surface and lower thermal stability but are sufficient for practical use. The resulting copolymers have a higher viscosity than the original chitosan, making them a promising thickener and stabilizer for food gels. Moreover, the copolymers exhibit an antibacterial effect, suggesting their potential use as a component in smart food packaging.

Unraveling the adaptive strategies of Mycoplasma hominis through proteogenomic profiling of clinical isolates.

Introduction: Mycoplasma hominis (M. hominis) belongs to the class Mollicutes, characterized by a very small genome size, reduction of metabolic pathways, including transcription factors, and the absence of a cell wall. Despite this, they adapt well not only to specific niches within the host organism but can also spread throughout the body, colonizing various organs and tissues. The adaptation mechanisms of M. hominis, as well as their regulatory pathways, are poorly understood. It is known that, when adapting to adverse conditions, Mycoplasmas can undergo phenotypic switches that may persist for several generations. Methods: To investigate the adaptive properties of M. hominis related to survival in the host, we conducted a comparative phenotypic and proteogenomic analysis of eight clinical isolates of M. hominis obtained from patients with urogenital infections and the laboratory strain H-34. Results: We have shown that clinical isolates differ in phenotypic features from the laboratory strain, form biofilms more effectively and show resistance to ofloxacin. The comparative proteogenomic analysis revealed that, unlike the laboratory strain, the clinical isolates possess several features related to stress survival: they switch carbon metabolism, activating the energetically least advantageous pathway of nucleoside utilization, which allows slowing down cellular processes and transitioning to a starvation state; they reconfigure the repertoire of membrane proteins; they have integrative conjugative elements in their genomes, which are key mediators of horizontal gene transfer. The upregulation of the methylating subunit of the restriction-modification (RM) system type I and the additional components of RM systems found in clinical isolates suggest that DNA methylation may play a role in regulating the adaptation mechanisms of M. hominis in the host organism. It has been shown that based on the proteogenomic profile, namely the genome sequence, protein content, composition of the RM systems and additional subunits HsdM, HsdS and HsdR, composition and number of transposable elements, as well as the sequence of the main variable antigen Vaa, we can divide clinical isolates into two phenotypes: typical colonies (TC), which have a high growth rate, and atypical (aTC) mini-colonies, which have a slow growth rate and exhibit properties similar to persisters. Discussion: We believe that the key mechanism of adaptation of M. hominis in the host is phenotypic restructuring, leading to a slowing down cellular processes and the formation of small atypical colonies. This is due to a switch in carbon metabolism and activation the pathway of nucleoside utilization. We hypothesize that DNA methylation may play a role in regulating this switch.

Conservation of the Rare and Endangered Vascular Plants in the Mining and Tourism Area: Khibiny Mountains, Murmansk Region, Russia.

The Khibiny Mountains (hereafter called Khibiny Mts.) are one of the most urbanized and industrialized regions in the Russian Arctic. There are combined a developed mining complex, elaborate infrastructure, a well-known tourist resort, and a large population, all amidst an exceptionally rich biodiversity of plants. In this study, we analyzed the current knowledge of the spatial distribution of rare and endangered vascular plants and vegetation and the impacts of human activities on these ecosystems. Approximately 28% of the protected vascular plant species in the Murmansk Region were registered within the confines of the Khibiny Mts. In particular, although only a handful of protected species had a widespread presence, most rare species were confined to the southern reaches of the mountain range, with only a select few extending into other parts. Papaver lapponicum was the only species that thrived across the entire territory, including industrial areas. The studied territory contained nine specially protected areas spanning 123,220 hectares. Nature monuments adjacent to mining sites and urban centers play an important role in preserving regional biodiversity. However, the expansion of the mining industry, alongside deforestation and wildfires, poses considerable threats to the biodiversity of the Khibiny Mts. A comprehensive biodiversity conservation strategy implemented in this region balances the local and expansive territorial protection of rare species and habitats, ensuring environmental preservation while facilitating social and economic progress, a noteworthy example of environmental protection in the Arctic.

Exploiting bacterial effector proteins to uncover evolutionarily conserved antiviral host machinery.

Arboviruses are a diverse group of insect-transmitted pathogens that pose global public health challenges. Identifying evolutionarily conserved host factors that combat arbovirus replication in disparate eukaryotic hosts is important as they may tip the balance between productive and abortive viral replication, and thus determine virus host range. Here, we exploit naturally abortive arbovirus infections that we identified in lepidopteran cells and use bacterial effector proteins to uncover host factors restricting arbovirus replication. Bacterial effectors are proteins secreted by pathogenic bacteria into eukaryotic hosts cells that can inhibit antimicrobial defenses. Since bacteria and viruses can encounter common host defenses, we hypothesized that some bacterial effectors may inhibit host factors that restrict arbovirus replication in lepidopteran cells. Thus, we used bacterial effectors as molecular tools to identify host factors that restrict four distinct arboviruses in lepidopteran cells. By screening 210 effectors encoded by seven different bacterial pathogens, we identify several effectors that individually rescue the replication of all four arboviruses. We show that these effectors encode diverse enzymatic activities that are required to break arbovirus restriction. We further characterize Shigella flexneri-encoded IpaH4 as an E3 ubiquitin ligase that directly ubiquitinates two evolutionarily conserved proteins, SHOC2 and PSMC1, promoting their degradation in insect and human cells. We show that depletion of either SHOC2 or PSMC1 in insect or human cells promotes arbovirus replication, indicating that these are ancient virus restriction factors conserved across invertebrate and vertebrate hosts. Collectively, our study reveals a novel pathogen-guided approach to identify conserved antimicrobial machinery, new effector functions, and conserved roles for SHOC2 and PSMC1 in virus restriction.

Biochemical and structural insights into a 5' to 3' RNA ligase reveal a potential role in tRNA ligation.

ATP-grasp superfamily enzymes contain a hand-like ATP-binding fold and catalyze a variety of reactions using a similar catalytic mechanism. More than 30 protein families are categorized in this superfamily, and they are involved in a plethora of cellular processes and human diseases. Here we identify C12orf29 as an atypical ATP-grasp enzyme that ligates RNA. Human C12orf29 and its homologs auto-adenylate on an active site Lys residue as part of a reaction intermediate that specifically ligates RNA halves containing a 5'-phosphate and a 3'-hydroxyl. C12orf29 binds tRNA in cells and can ligate tRNA within the anticodon loop in vitro. Genetic depletion of c12orf29 in female mice alters global tRNA levels in brain. Furthermore, crystal structures of a C12orf29 homolog from Yasminevirus bound to nucleotides reveal a minimal and atypical RNA ligase fold with a unique active site architecture that participates in catalysis. Collectively, our results identify C12orf29 as an RNA ligase and suggest its involvement in tRNA biology.

Effect of temporal thermal stress on Penaeus vannamei: Growth performance and physiological plasticity.

The present study evaluated the effect of temporal periods of hypothermia and hyperthermia, followed by an optimal temperature recovery phase on the growth, survival, and physiological response of Penaeus vannamei. Post-larvae were exposed to stress periods for 7 and 14 days at 22 °C and 32 °C each, followed by a recovery phase at 28 °C to complete seven experimental weeks, and were compared with a control group maintained at 28 °C. Weight gain, specific growth rate, feed intake, feed conversion ratio, and survival were weekly determined. Muscle, hepatopancreas, and hemolymph were sampled on the 14th day of the recovery phase for biochemical composition, and antioxidant and digestive enzyme activities determination. The shrimp presented a higher growth rate during short-term hyperthermia in contrast to shrimp under hypothermia that presented compensatory growth after thermal stress when the temperature was restored at 28 °C. Hyperthermia increased 12-13% the feed intake while this was diminished 21-29% by the hypothermia periods. Shrimp undergo metabolic adjustments following thermal stress, with short hypothermia increasing the lipase activity and lipid storage in the hepatopancreas, while short hyperthermia also enhances chymotrypsin activity and leads to higher protein and lipid accumulation. Conversely, prolonged hyperthermia induces greater energy consumption, depleting lipid and glycogen stores, while hypothermia causes scarce mobilization of energy reserves during recovery phase. Antioxidant enzyme activities were not affected by short-thermal stress (7d), while prolonged thermal stress (14d) significantly affected SOD, CAT, and GPx activities. The present study provides important insights into the physiological plasticity of P. vannamei during recovery from thermal stress.

Extensive long-range polycomb interactions and weak compartmentalization are hallmarks of human neuronal 3D genome.

Chromatin architecture regulates gene expression and shapes cellular identity, particularly in neuronal cells. Specifically, polycomb group (PcG) proteins enable establishment and maintenance of neuronal cell type by reorganizing chromatin into repressive domains that limit the expression of fate-determining genes and sustain distinct gene expression patterns in neurons. Here, we map the 3D genome architecture in neuronal and non-neuronal cells isolated from the Wernicke's area of four human brains and comprehensively analyze neuron-specific aspects of chromatin organization. We find that genome segregation into active and inactive compartments is greatly reduced in neurons compared to other brain cells. Furthermore, neuronal Hi-C maps reveal strong long-range interactions, forming a specific network of PcG-mediated contacts in neurons that is nearly absent in other brain cells. These interacting loci contain developmental transcription factors with repressed expression in neurons and other mature brain cells. But only in neurons, they are rich in bivalent promoters occupied by H3K4me3 histone modification together with H3K27me3, which points to a possible functional role of PcG contacts in neurons. Importantly, other layers of chromatin organization also exhibit a distinct structure in neurons, characterized by an increase in short-range interactions and a decrease in long-range ones.

A Pediatric Gastric Dieulafoy Lesion: A Case Report and Literature Review.

This report presents a case of a 16-year-old male with severe upper gastrointestinal bleeding caused by a Dieulafoy lesion (DL). A DL is a rare but life-threatening condition characterized by sudden and massive bleeding from a small arterial vessel in the gastrointestinal (GI) tract. Diagnosis is often made through esophagogastroduodenoscopy (EGD), which reveals an enlarged submucosal blood vessel. The patient was successfully treated with adrenaline injection and hemoclipping during EGD. This case highlights the importance of considering a DL as a potential cause of severe upper GI bleeding in pediatric patients and emphasizes the significance of early recognition and intervention to achieve favorable outcomes. Additional investigation is required to enhance our comprehension of the occurrence, etiology, and most effective approaches to managing DLs in pediatric patients.

Distinct Prostate Cancer Survival Outcomes in Firefighters: A Population-Based Study.

Introduction: Survival outcomes for prostate cancer among specific occupational groups prone to regular medical check-ups vis-à-vis the general population have been understudied. For firefighters, a demographic subject to rigorous medical evaluations, possessing above-average medical expertise, and exposed to specific carcinogens of interest, prostate cancer survival in the US has never been studied. Methods: We conducted a retrospective study, utilizing data from the Florida Cancer Data System spanning 2004 to 2014, coupled with firefighter certification records from the Florida State Fire Marshal's Office. Our study cohort consisted of 1058 prostate cancer cases among firefighters as well as prostate cases for the Florida general population (n = 150,623). We compared cause-specific survival between the two using Cox regression models adjusted for demographics and clinical characteristics, including PSA levels, Gleason scores, and treatment modalities. Results: Firefighters demonstrated a higher five-year cause-specific survival rate (96.1%, 95% CI: 94.7-97.1%) than the general population (94.2%, 95%CI: 94.1-94.3%). Overall, firefighters' diagnoses were established at younger ages (median age 63 vs. 67 in the general population), exhibited a higher proportion of localized stage cancers (84.7% vs. 81.1%), and had a greater utilization of surgery (46.4% vs. 37.6%), a treatment modality with a high success rate but potential side effects. In multivariable analysis, firefighters displayed a survival advantage for localized stage (adjusted hazard ratio [aHR] = 0.53; 95%CI: 0.34-0.82). However, for regional or distant stages, firefighters aged 65 and above exhibited a higher risk of death (aHR = 1.84; 95% CI: 1.18-2.86) than the general population. Conclusion: Firefighters experience enhanced prostate cancer survival, primarily in cases diagnosed at localized stages, likely due to increased PSA testing. Nonetheless, for regional or distant stage, survival among older firefighters' lags behind that of the general population. Further investigations are warranted to unravel factors influencing the development of aggressive disease beyond PSA and Gleason scores in this population, as well as to assess the impact of a higher rate of surgical treatment on firefighters' quality of life.

Towards establishing a fungal economics spectrum in soil saprobic fungi.

Trait-based frameworks are promising tools to understand the functional consequences of community shifts in response to environmental change. The applicability of these tools to soil microbes is limited by a lack of functional trait data and a focus on categorical traits. To address this gap for an important group of soil microorganisms, we identify trade-offs underlying a fungal economics spectrum based on a large trait collection in 28 saprobic fungal isolates, derived from a common grassland soil and grown in culture plates. In this dataset, ecologically relevant trait variation is best captured by a three-dimensional fungal economics space. The primary explanatory axis represents a dense-fast continuum, resembling dominant life-history trade-offs in other taxa. A second significant axis reflects mycelial flexibility, and a third one carbon acquisition traits. All three axes correlate with traits involved in soil carbon cycling. Since stress tolerance and fundamental niche gradients are primarily related to the dense-fast continuum, traits of the 2nd (carbon-use efficiency) and especially the 3rd (decomposition) orthogonal axes are independent of tested environmental stressors. These findings suggest a fungal economics space which can now be tested at broader scales.

A domain-swapped CaMKII conformation facilitates linker-mediated allosteric regulation.

Ca2+ signaling plays a key role in physiological processes such as memory formation and cardiac function. Ca2+/calmodulin-dependent protein kinase II (CaMKII) is the primary kinase that responds to Ca2+ inputs in these cells. There are four CaMKII paralogs in mammals which are alternatively spliced in the variable linker region to create upwards of 70 different variants. In this study, we systematically studied different linker regions and determined that the position of charged residues within the linker region modulates the Ca2+/CaM sensitivity of the holoenzyme. We present an X-ray crystal structure of full-length CaMKIIδ that shows a domain-swapped conformation of the subunits within the dodecameric holoenzyme. In this structure, the kinase domain of one subunit is docked onto the hub domain of a different subunit, providing an additional interface within the holoenzyme. Mutations at the equatorial and lateral interfaces revealed that the kinase-hub interaction dissociates as the hub-hub interfaces are disturbed, which led alterations in the stoichiometry of CaMKII holoenzyme and Ca2+/CaM sensitivity. Molecular dynamics simulations of linker-containing domain-swapped and non-domain-swapped CaMKIIs reveal that the domain-swapped configuration facilitates an interaction between the calmodulin binding domain and the variable linker region, such that dynamic electrostatic forces between charges on these segments can modulate the equilibrium between the compact and extended conformational states of the holoenzyme. Small angle X-ray scattering data confirms that a negatively charged linker CaMKII holoenzyme adopts a more compact conformation compared to a positively charged linker. These data support a model where patches of charged linker residues interact with the calmodulin binding domain to allosterically regulate sensitivity to Ca2+/CaM. Our findings provide a new framework for understanding CaMKII structure and allosteric regulation by the variable linker region in Ca2+-sensitive cells.

Increasing mental health issues in college students from 2016-2019: Assessing the intersections of race/ethnicity, gender, and sexual orientation.

BACKGROUND: This study aimed to evaluate how trends in mental health (e.g., diagnosis/treatment of depression, anxiety, suicidal ideation) varied across intersections of gender, race/ethnicity, and sexual orientation in a large, national sample of undergraduate students. METHODS: Data from the American College Health Association, and National College Health Assessment II: 2016-2019 were analyzed (N = 228,640 undergraduate students from 442 campuses, ages 18-24; 67.8 % female, 40.4 % BIPOC, 3.0 % non-binary (trans/non-conforming), 19.4 % LGBQ+). We used logistic regression to predict each mental health indicator; covariates included year, gender, BIPOC, LGBQ+ status, and their interactions, as well as other covariate controls (e.g., region, year in school). RESULTS: There were significant and steady increases in the odds of each mental health indicator by year (ORs = 1.12-1.13), which were significantly greater in magnitude for LGBQ+ students (ORs = 1.20-1.23). Increases did not vary by gender, race/ethnicity, or intersections between these groups and LGBQ+ status. There were significant interactions between identity groups that aligned with intersectional and minority stress theories (which did not vary by year). Non-Hispanic White students had significantly greater odds of past-year treatment/diagnosis of depression and anxiety compared to BIPOC students; however, BIPOC students had significantly greater odds of past-year suicidal ideation and this was pronounced for BIPOC women. Being non-binary x LGBQ+ was associated with significantly greater odds of each indicator. DISCUSSION: Results affirm the importance of promoting mental health among college students, with a particular focus on how to better serve and support BIPOC, non-binary, and LGBQ+ students.

Infection with different Neospora caninum strains causes differences in the glycosylation pattern in the uteri and placentae of Neospora caninum-infected heifers.

Neospora caninum is an obligate intracellular parasite that causes abortion in ruminants. Different strains produce differences in the severity of disease outcomes. These differences may cause physiological or pathological changes in cells, modifying the intercellular interactions and intracellular transport pathways that could be evidenced by identifying the terminal sugars. This study aimed to characterize the oligosaccharide pattern in the bovine placenta and uterus after infection with tachyzoites of three different strains of N. caninum (Nc-1, Nc-6 Argentina and Nc Spain-7) during early gestation. Fourteen heifers were inoculated intravenously on day 70 of gestation with 2 × 108 N. caninum tachyzoites and samples of placentae and uteri were analysed by histology and lectin histochemistry. In the infected groups, severe placentitis was associated with changes in lectin binding in the vascular endothelium by Lens culinaris agglutinin (LCA), Pisum sativum agglutinin (PSA) and Ricinus communis I (RCA-I) lectins, in the epithelial cells of the endometrial glands by RCA-I, Dolichos biflorus agglutinin (DBA), succinylated wheat germ agglutinin, peanut agglutinin (PNA), concanavalin-A (CON-A), LCA, PSA and Phaseolus vulgaris erythroagglutinin (PHA-e), and in the trophoblast layer by PNA, CON-A, LCA, PSA, PHA-e, soybean agglutinin, RCA-I, DBA and Bandieraea simplicifolia agglutinin (BSA-I). The results suggest that N. caninum causes changes in the glycosylation pattern in the maternofetal interface tissues and might cause abortions in early gestation due to changes in the cellular structure of the placenta.

One-Pot Microfluidics to Engineer Chitosan Nanoparticles Conjugated with Antimicrobial Peptides Using "Photoclick" Chemistry: Validation Using the Gastric Bacterium Helicobacter pylori.

Surface bioconjugation of antimicrobial peptides (AMP) onto nanoparticles (AMP-NP) is a complex, multistep, and time-consuming task. Herein, a microfluidic system for the one-pot production of AMP-NP was developed. Norbornene-modified chitosan was used for NP production (NorChit-NP), and thiolated-AMP was grafted on their surface via thiol-norbornene "photoclick" chemistry over exposure of two parallel UV LEDs. The MSI-78A was the AMP selected due to its high activity against a high priority (level 2) antibiotic-resistant gastric pathogen: Helicobacter pylori (H. pylori). AMP-NP (113 ± 43 nm; zeta potential 14.3 ± 7 mV) were stable in gastric settings without a cross-linker (up to 5 days in pH 1.2) and bactericidal against two highly pathogenic H. pylori strains (1011 NP/mL with 96 µg/mL MSI-78A). Eradication was faster for H. pylori 26695 (30 min) than for H. pylori J99 (24 h), which was explained by the lower minimum bactericidal concentration of soluble MSI-78A for H. pylori 26695 (32 µg/mL) than for H. pylori J99 (128 µg/mL). AMP-NP was bactericidal by inducing H. pylori cell membrane alterations, intracellular reorganization, generation of extracellular vesicles, and leakage of cytoplasmic contents (transmission electron microscopy). Moreover, NP were not cytotoxic against two gastric cell lines (AGS and MKN74, ATCC) at bactericidal concentrations. Overall, the designed microfluidic setup is a greener, simpler, and faster approach than the conventional methods to obtain AMP-NP. This technology can be further explored for the bioconjugation of other thiolated-compounds.