Renal medulla in hypertension

Abstract: Studies have found that blood flow to the renal medulla is an important determinant of pressure-natriuresis and the long-term regulation of arterial pressure. First, a brief review of methods developed enabling the study of the medullary circulation is presented. Second, studies performed in rats are presented showing medullary blood flow plays a vital role in the pressure-natriuresis relationship and thereby in hypertension. Third, it is shown that chronic reduction of medullary blood flow results in hypertension and that enhancement of medullary blood flow reduces hypertension hereditary models of both salt-sensitive rats and salt-resistant forms of hypertension. The key role that medullary nitric oxide production plays in protecting this region from ischemic injury associated with circulating vasoconstrictor agents and reactive oxygen species is presented. The studies cited are largely the work of my students, research fellows, and colleagues with whom I have performed these studies dating from the late 1980s to more recent years.

The Ethanolic Extract of Polygala paniculata L. Blocks Panx1 Channels and Reduces Ischemic Brain Infarct in a Dose- and Sex-Dependent Way.

Polygala paniculata L. is a native plant from tropical America. The therapeutic potential of the hydroalcoholic extract of P. paniculata (HEPp) has been scientifically explored due to folk medicine reports on its action against several afflictions. HEPp contains several bioactive molecules with neuroprotective activities, making it a promising candidate for stroke treatment. This study used electrophysiological, biochemical, and in vivo experiments to evaluate the molecular mechanisms underlying HEPp as a neuroprotective therapy for stroke targeting Pannexin-1 (Panx1). Panx1 is a non-selective channel that opens during ischemia and contributes to neuronal death. HEPp was not toxic to cortical neurons and pre-treatment with the extract reduced neuronal death promoted by oxygen and glucose deprivation in a dose-dependent manner. Additionally, HEPp blocked Panx1 currents in a dose-dependent manner and the effect, which was shown to be partially due to rutin. Animals submitted to photothrombosis and post-treated with HEPp had reduced infarct volume, and the effective dose was lower in males (1 mg/kg) than in females (10 mg/kg). On the other hand, in Panx1 KD mice (50% Panx1 levels), the acute treatment reduced the infarct volume only in males. Upon chronic treatment with HEPp, a reduction in Panx1 protein levels was observed. The current study provides reliable evidence of the neuroprotective properties of HEPp in both in vitro and in vivo models of stroke. The underlying mechanism involves, at least in part, the inhibition of Panx1 channel function and possibly downregulation of protein levels, suppressing the secondary events that lead to apoptosis and inflammation.

The need to diversify genomic studies: Insights from Andean highlanders and Amazonians.

More globally diverse perspectives are needed in genomic studies and precision medicine practices on non-Europeans. Here, we illustrate this by discussing the distribution of clinically actionable genetic variants involved in drug response in Andean highlanders and Amazonians, considering their environment, history, genetic structure, and historical biases in the perception of biological diversity of Native Americans.

Phytobacter spp: the emergence of a new genus of healthcare-associated Enterobacterales encoding carbapenemases in Argentina: a case series.

Members of the genus Phytobacter (order Enterobacterales) are isolated from the natural environment and clinical settings. Identification of Phytobacter strains based on biochemical characteristics is complicated due to taxonomic confusion, and they are often misidentified by automated identification systems in laboratories. In this study we describe the first three clinical cases associated with Phytobacter spp. reported in Argentina. We describe the identification, the molecular analysis using whole genome sequencing and the potential clinical relevance.

Comparison of Hybribio-H13 and Hybrid Capture® 2 human papillomavirus tests for detection of CIN2+ and CIN3. / Comparación de las pruebas para el virus del papiloma humano Hybribio-H13 y Hybrid Capture® 2 para la detección de NIC2+ y NIC3+

INTRODUCTION: Low-cost, accurate high-risk HPV tests are needed for cervical cancer screening in limited-resource settings. OBJECTIVE: To compare the performance of the low-cost Hybribio-H13 test with the Hybrid Capture® 2 to detect cervical intraepithelial neoplasia grade 2 or 3 (CIN2 and CIN3). MATERIALS AND METHODS: Archived baseline samples tested by the Hybrid Capture® 2 from women of the ASCUS-COL trial, aged 20 to 69 years, with biopsy-colposcopy directed diagnosis of CIN2+ (n = 143), CIN3+ (n = 51), and < CIN2 (n = 632) were blindly tested by the Hybribio-H13 test. RESULTS: The relative sensitivity of the Hybribio-H13 test versus the Hybrid Capture® 2 for detecting CIN2+ was 0.89 (90% CI = 0,80-0,98; NIT = 0,66), and for CIN3+ was 0,92 (90% CI = 0,85-0,98; NIT = 0,35). Relative specificity was 1.19 (90% CI = 1.05-1.33; NIT <0.00001). In the analysis restricted to women older than 30 years, the relative sensitivity of the Hybribio-H13 for CIN3+ was marginally below unity (ratio = 0.97; 90% CI = 0.95-0.99), and the specificity remained higher than the Hybrid Capture® 2 test. CONCLUSION: The Hybribio-H13 test was as specific as the Hybrid Capture® 2 for detecting CIN2+ or CIN3+ but less sensitive. Considering these results and the young age of the population recruited for screening because of ASCUS cytology, we suggest our results warrant the evaluation of the Hybribio-H13 for screening cervical cancer, especially in the evaluated population.

Introducción. Se necesitan pruebas para detectar genotipos de VPH de alto riesgo, precisas y de bajo costo, para la tamización del cáncer de cuello uterino en entornos de recursos limitados. Objetivo. Comparar el desempeño de la prueba de bajo costo Hybrid-H13 con la de Hybrid Capture® 2 para detectar NIC2+ y NIC3+. Materiales y métodos. Se analizaron en ciego muestras de la línea base provenientes de mujeres del estudio ASCUS-COL, entre los 20 y los 69 años, con diagnóstico dirigido por biopsia-colposcopia de NIC2+ (n = 143), NIC3 + (n = 51) y < NIC2 (n = 632) con la prueba para detección de virus de papiloma humano Hybribio-H13. Estas muestras fueron previamente evaluadas con la prueba Hybrid Capture® 2. Resultados. La sensibilidad relativa de Hybribio-13 versus la de Hybrid Capture® 2 para detectar NIC2+ fue de 0,89 (IC90%: 0,80-0,98; NIT = 0,66) y para NIC3+ fue de 0,92 (IC90%: 0,85-0,98; NIT = 0,35). La especificidad relativa fue de 1,19 (IC90%: 1,05-1,33; NIT <0,00001). En el análisis restringido a mujeres mayores de 30 años, la sensibilidad relativa de Hybribio-H13 para NIC3+ estuvo marginalmente por debajo de la unidad (proporción = 0,97; IC90%: 0,95-0,99) y la especificidad permaneció más alta que la de la prueba Hybrid Capture® 2. Conclusión. La prueba de Hybribio-H13 fue tan específica como la de Hybrid Capture® 2, pero menos sensible para detectar NIC2+ o NIC3+. Teniendo en cuenta estos resultados y la temprana edad de la población reclutada en la tamización por la presencia de ASCUS en la citología, se sugiere continuar con la evaluación de la prueba Hybribio-H13 para la detección de cáncer de cuello uterino en poblaciones con las mismas características que las de la aquí evaluada.

Targeting inflammasome complexes as a novel therapeutic strategy for mood disorders.

INTRODUCTION: Inflammasome complexes, especially NLRP3, have gained great attention as a potential therapeutic target in mood disorders. NLRP3 triggers a caspase 1-dependent release of the inflammatory cytokines IL-1ß and IL-18, and seems to interact with purinergic and kynurenine pathways, all of which are implicated in mood disorders development and progression. AREAS COVERED: Emerging evidence supports NLRP3 inflammasome as a promising pharmacological target for mood disorders. We discussed the available evidence from animal models and human studies and provided a reflection on drawbacks and perspectives for this novel target. EXPERT OPINION: Several studies have supported the involvement of NLRP3 inflammasome in MDD. However, most of the evidence comes from animal models. The role of NLRP3 inflammasome in BD as well as its anti-manic properties is not very clear and requires further exploration. There is evidence of anti-manic effects of P2×R7 antagonists associated with reduction in the brain levels of IL-1ß and TNF-α in a murine model of mania. The involvement of other NLRP3 inflammasome expressing cells besides microglia, like astrocytes, and of other inflammasome complexes in mood disorders also deserves further investigation. Preclinical and clinical characterization of NLRP3 and other inflammasomes in mood disorders is needed before considering translational approaches, including clinical trials.

Understanding microchromosomal organization and evolution in four representative woodpeckers (Picidae, Piciformes) through BAC-FISH analysis.

The genome organization of woodpeckers has several distinctive features e.g., an uncommon accumulation of repetitive sequences, enlarged Z chromosomes, and atypical diploid numbers. Despite the large diversity of species, there is a paucity of detailed cytogenomic studies for this group and we thus aimed to rectify this. Genome organization patterns and hence evolutionary change in the microchromosome formation of four species (Colaptes campestris, Veniliornis spilogaster, Melanerpes candidus, and Picumnus nebulosus) was established through fluorescence in situ hybridization using bacterial artificial chromosomes originally derived from Gallus gallus and Taeniopygia guttata. Findings suggest that P. nebulosus (2n = 110), which was described for the first time, had the most basal karyotype among species of Picidae studied here, and probably arose as a result of fissions of avian ancestral macrochromosomes. We defined a new chromosomal number for V. spilogaster (2n = 88) and demonstrated microchromosomal rearrangements involving C. campestris plus a single, unique hitherto undescribed rearrangement in V. spilogaster. This comprised an inversion after a fusion involving the ancestral microchromosome 12 (homologous to chicken microchromosome 12). We also determined that the low diploid number of M. candidus is related to microchromosome fusions. Woodpeckers thus exhibit significantly rearranged karyotypes compared to the putative ancestral karyotype.

Improvement Science Increases Routine Lipid Screening in General Pediatric Cardiology.

OBJECTIVE: To evaluate the effectiveness of patient education, physician counseling, and point-of-care (POC) testing on improving adherence to lipid screening national guidelines in a general pediatric cardiology practice (2017-2023). STUDY DESIGN: Regional primary care providers were surveyed regarding lipid screening practices. Key drivers were categorized (physician, patient, and system) with corresponding interventions. Pediatric cardiologists started offering lipid screening during regular visits by providing families with preventive cardiovascular education materials and lab phlebotomy testing. System redesign included educational posters, clinical intake protocol, physician counseling, electronic health record integration, and POC testing. Run charts and statistical process control charts measured screening rates and key processes. RESULTS: The primary care survey response rate was 32% (95/294); 97% supported pediatric cardiologists conducting routine lipid screening. Pediatric cardiology mean baseline lipid screening rate was 0%, increased to 7% with patient education, and to 61% after system redesign including POC testing. Screening rates among 1467 patients were similar across age groups (P = .98). More patients received lipid screening by POC (91.7%) compared with phlebotomy (8.3%). Lipid abnormalities detected did not differ by screening methodology (P = .49). CONCLUSION: Patient education, counseling, and POC testing improved adherence to national lipid screening guidelines, providing a possible model for primary care implementation.

Genetic variability of Aedes aegypti (Diptera: Culicidae) in El Salvador and Honduras: presence of a widespread haplotype and implications for mosquito control.

BACKGROUND: This study examined population genetics of Aedes aegypti in El Salvador and Honduras, two adjacent countries in Central America. Aedes aegypti is associated with yellow fever, dengue, chikungunya, and Zika. Each year, thousands of cases of dengue are typically reported in El Salvador and Honduras. METHODS: In El Salvador, collections were obtained from five Departments. In Honduras, samples were obtained from six municipalities in four Departments. Mitochondrial DNA cytochrome oxidase I (COI) was sequenced, and consensus sequences were combined with available sequences from El Salvador to determine haplotype number, haplotype diversity, nucleotide diversity, and Tajima's D. A haplotype network was produced to examine the relationship between genotypes. RESULTS: In El Salvador, there were 17 haplotypes, while in Honduras there were 4 haplotypes. In both El Salvador and Honduras, Haplotype 1 is most abundant and widespread. In El Salvador, haplotype H2 was also widespread in 10 of 11 sampled municipalities, but it was not present in Honduras. The capital of El Salvador (San Salvador) and the eastern region of ES had the highest haplotype diversity of regions sampled. CONCLUSIONS: Haplotype 1 and H2 each belong to different phylogenetic lineages of Ae. aegypti. The most geographically widespread haplotype (H1) may have been present the longest and could be a remnant from previous eradication programs. These data may contribute to future control programs for Ae. aegypti in the two countries.

Comparison of Hybribio-H13 and Hybrid Capture® 2 human papillomavirus tests for detection of CIN2+ and CIN3+ / Comparación de las pruebas para el virus del papiloma humano Hybribio-H13 y Hybrid Capture® 2 para la detección de NIC2+ y NIC3+

Abstract Introduction. Low-cost, accurate high-risk HPV tests are needed for cervical cancer screening in limited-resource settings. Objective. To compare the performance of the low-cost Hybribio-H13 test with the Hybrid Capture® 2 to detect cervical intraepithelial neoplasia grade 2 or 3 (CIN2 and CIN3). Materials and methods. Archived baseline samples tested by the Hybrid Capture® 2 from women of the ASCUS-COL trial, aged 20 to 69 years, with biopsy-colposcopy directed diagnosis of CIN2+ (n = 143), CIN3+ (n = 51), and < CIN2 (n = 632) were blindly tested by the Hybribio-H13 test. Results. The relative sensitivity of the Hybribio-H13 test versus the Hybrid Capture® 2 for detecting CIN2+ was 0.89 (90% CI = 0,80-0,98; NIT = 0,66), and for CIN3+ was 0,92 (90% CI = 0,85-0,98; NIT = 0,35). Relative specificity was 1.19 (90% CI = 1.05-1.33; NIT < 0.00001). In the analysis restricted to women older than 30 years, the relative sensitivity of the Hybribio-H13 for CIN3+ was marginally below unity (ratio = 0.97; 90% CI = 0.95-0.99), and the specificity remained higher than the Hybrid Capture® 2 test. Conclusion. The Hybribio-H13 test was as specific as the Hybrid Capture® 2 for detecting CIN2+ or CIN3+ but less sensitive. Considering these results and the young age of the population recruited for screening because of ASCUS cytology, we suggest our results warrant the evaluation of the Hybribio-H13 for screening cervical cancer, especially in the evaluated population.

Resumen Introducción. Se necesitan pruebas para detectar genotipos de VPH de alto riesgo, precisas y de bajo costo, para la tamización del cáncer de cuello uterino en entornos de recursos limitados. Objetivo. Comparar el desempeño de la prueba de bajo costo Hybrid-H13 con la de Hybrid Capture® 2 para detectar NIC2+ y NIC3+. Materiales y métodos. Se analizaron en ciego muestras de la línea base provenientes de mujeres del estudio ASCUS-COL, entre los 20 y los 69 años, con diagnóstico dirigido por biopsia-colposcopia de NIC2+ (n = 143), NIC3 + (n = 51) y < NIC2 (n = 632) con la prueba para detección de virus de papiloma humano Hybribio-H13. Estas muestras fueron previamente evaluadas con la prueba Hybrid Capture® 2. Resultados. La sensibilidad relativa de Hybribio-13 versus la de Hybrid Capture® 2 para detectar NIC2+ fue de 0,89 (IC90%: 0,80-0,98; NIT = 0,66) y para NIC3+ fue de 0,92 (IC90%: 0,85-0,98; NIT = 0,35). La especificidad relativa fue de 1,19 (IC90%: 1,05-1,33; NIT < 0,00001). En el análisis restringido a mujeres mayores de 30 años, la sensibilidad relativa de Hybribio-H13 para NIC3+ estuvo marginalmente por debajo de la unidad (proporción = 0,97; IC90%: 0,95-0,99) y la especificidad permaneció más alta que la de la prueba Hybrid Capture® 2. Conclusión. La prueba de Hybribio-H13 fue tan específica como la de Hybrid Capture® 2, pero menos sensible para detectar NIC2+ o NIC3+. Teniendo en cuenta estos resultados y la temprana edad de la población reclutada en la tamización por la presencia de ASCUS en la citología, se sugiere continuar con la evaluación de la prueba Hybribio-H13 para la detección de cáncer de cuello uterino en poblaciones con las mismas características que las de la aquí evaluada.

Bacillus velezensis iturins inhibit the hemolytic activity of Staphylococcus aureus.

Bovine mastitis caused by S. aureus has a major economic impact on the dairy sector. With the crucial need for new therapies, anti-virulence strategies have gained attention as alternatives to antibiotics. Here we aimed to identify novel compounds that inhibit the production/activity of hemolysins, a virulence factor of S. aureus associated with mastitis severity. We screened Bacillus strains obtained from diverse sources for compounds showing anti-hemolytic activity. Our results demonstrate that lipopeptides produced by Bacillus spp. completely prevented the hemolytic activity of S. aureus at certain concentrations. Following purification, both iturins, fengycins, and surfactins were able to reduce hemolysis caused by S. aureus, with iturins showing the highest anti-hemolytic activity (up to 76% reduction). The lipopeptides showed an effect at the post-translational level. Molecular docking simulations demonstrated that these compounds can bind to hemolysin, possibly interfering with enzyme action. Lastly, molecular dynamics analysis indicated general stability of important residues for hemolysin activity as well as the presence of hydrogen bonds between iturins and these residues, with longevous interactions. Our data reveals, for the first time, an anti-hemolytic activity of lipopeptides and highlights the potential application of iturins as an anti-virulence therapy to control bovine mastitis caused by S. aureus.

Dietary Hydroxytyrosol Supplementation on Growth Performance, Gut Morphometry, and Oxidative and Inflammatory Status in LPS-Challenged Broilers.

This study assessed the effects of hydroxytyrosol (HT) on 8- to 20-day-old broilers challenged with lipopolysaccharide (LPS); 180 Cobb500™ male chicks were randomly assigned to 3 treatment groups, each comprising 10 replicates with 6 birds per replicate. Treatments included a control diet (CON), CON with LPS administration, and CON + LPS supplemented with 10 mg of HT/kg of feed. LPS was administered intraperitoneally on days 14, 16, 18, and 20. Body weight (BW), body weight gain (BWG), and the feed conversion ratio (FCR) were measured. On day 20, ten birds per treatment were slaughtered for analysis. Bursa, spleen, and liver were collected, and their respective relative weight was determined. The jejunum was destined for morphological analyses of villus height (VH), crypt depth (CD), and their ratio (VH:CD), and for mRNA expression of nuclear factor kappa B (NF-κB), catalase (CAT), glutathione peroxidase (GPx), superoxide dismutase (SOD), and interleukins 10 (IL-10), 1 beta (IL-1ß), and 8 (IL-8). HT improved BW, BWG, and FCR, and reduced crypt depth (CD) while increasing the VH:CD ratio in the jejunum. Moreover, HT downregulated mRNA expression of CAT, GPx, IL-10, and IL-1ß. In conclusion, HT enhances broiler growth performance, mitigates jejunal mucosa damage from LPS, and modulates antioxidant and immune responses.

Mapping Human Resources to Guide Ophthalmology Capacity-Building Projects in Honduras: Sub-national Analyses of Physician Distribution and Surgical Practices.

Objective: To map ophthalmologist locations and surgical practices as they vary sub-nationally within Honduras to maximize the impact of efforts to develop cataract surgical capacity. Methods: An anonymous survey was sent to all Honduran ophthalmologists with questions on surgical volume, department-level location, type of facility in which they work, surgical methods, and age. Surgical volume, population, and poverty data sourced through the Oxford Poverty Human Development Initiative were mapped at the department level, and cataract surgical rates (CSR; surgeries per million population per year) were calculated and mapped. Results: Sixty-one of the 102 Honduran ophthalmologists contacted responded. Of those, 85% perform cataract surgery, and 49% work at least part time in a non-profit or governmental facility. Honduras has fewer surgical ophthalmologists per million than the global average, and though national CSR appears to be increasing, it varies significantly between departments. The correlation between CSR and poverty is complex, and outliers provide valuable insights. Conclusion: Mapping ophthalmological surgical practices as they relate to population and poverty at a sub-national level provides important insights into geographic trends in the need for and access to eye care. Such insights can be used to guide efficient and effective development of cataract surgical capacity.

Fuchs endothelial corneal dystrophy: an updated review.

PURPOSE: The present review will summarize FECD-associated genes and pathophysiology, diagnosis, current  therapeutic approaches, and future treatment perspectives. METHODS: Literature review. RESULTS: Fuchs' endothelial corneal dystrophy (FECD) is the most common bilateral corneal dystrophy and accounts for one-third of all corneal transplants performed in the US. FECD is caused by a combination of genetic and non-heritable factors, and there are two types: early-onset FECD, which affects individuals from an early age and is usually more severe, and late-onset FECD, which is more common and typically manifests around the age of 40. The hallmark findings of FECD include progressive loss of corneal endothelial cells and the formation of focal excrescences (guttae) on the Descemet membrane. These pathophysiological changes result in progressive endothelial dysfunction, leading to a decrease in visual acuity and blindness in later stages. The present review will summarize FECD-associated genes and pathophysiology, diagnosis, current therapeutic approaches, and future treatment perspectives. CONCLUSION: With the characterization and understanding of FECD-related genes and ongoing research into regenerative therapies for corneal endothelium, we can hope to see more significant improvements in the future in the management and care of the disease.

Chikungunya infection in returned travellers: results from the geosentinel network, 2005-2020.

BACKGROUND: Chikungunya is an important travel-related disease because of its rapid geographical expansion and potential for prolonged morbidity. Improved understanding of the epidemiology of travel-related chikungunya infections may influence prevention strategies including education and vaccination. METHODS: We analysed data from travellers with confirmed or probable chikungunya reported to GeoSentinel sites from 2005 to 2020. Confirmed chikungunya was defined as a compatible clinical history plus either virus isolation, positive nucleic acid test or seroconversion/rising titre in paired sera. Probable chikungunya was defined as a compatible clinical history with a single positive serology result. RESULTS: 1202 travellers (896 confirmed and 306 probable) with chikungunya were included. The median age was 43 years (range 0-91; interquartile range [IQR]: 31-55); 707 (58.8%) travellers were female. Most infections were acquired in the Caribbean (28.8%), Southeast Asia (22.8%), South Central Asia (14.2%) and South America (14.2%). The highest numbers of chikungunya cases reported to GeoSentinel were in 2014 (28.3%), 2015 (14.3%) and 2019 (11.9%). The most frequent reasons for travel were tourism (n = 592; 49.3%) and visiting friends or relatives (n = 334; 27.7%). The median time to presentation to a GeoSentinel site was 23 days (IQR: 7-52) after symptom onset. In travellers with confirmed chikungunya and no other reported illnesses, the most frequently reported symptoms included musculoskeletal symptoms (98.8%), fever/chills/sweats (68.7%) and dermatologic symptoms (35.5%). Among 917 travellers with information available, 296 (32.3%) had a pretravel consultation. CONCLUSIONS: Chikungunya was acquired by international travellers in almost 100 destinations globally. Vector precautions and vaccination where recommended should be integrated into pretravel visits for travellers going to areas with chikungunya or areas with the potential for transmission. Continued surveillance of travel-related chikungunya may help public health officials and clinicians limit the transmission of this potentially debilitating disease by defining regions where protective measures (e.g. pretravel vaccination) should be strongly considered.

Intestinal protozoa in returning travellers: a GeoSentinel analysis from 2007 to 2019.

BACKGROUND: Prolonged diarrhoea is common amongst returning travellers and is often caused by intestinal protozoa. However, the epidemiology of travel-associated illness caused by protozoal pathogens is not well described. METHODS: We analysed records of returning international travellers with illness caused by Giardia duodenalis, Cryptosporidium spp., Cyclospora cayetanensis or Cystoisospora belli, reported to the GeoSentinel Network during January 2007-December 2019. We excluded records of travellers migrating, with an unascertainable exposure country, or from GeoSentinel sites that were not located in high-income countries. RESULTS: There were 2517 cases, 82.3% giardiasis (n = 2072), 11.4% cryptosporidiosis (n = 287), 6.0% cyclosporiasis (n = 150) and 0.3% cystoisosporiasis (n = 8). Overall, most travellers were tourists (64.4%) on long trips (median durations: 18-30 days). Cryptosporidiosis more frequently affected people < 18 years (13.9%) and cyclosporiasis affected people ≥ 40 years (59.4%). Giardiasis was most frequently acquired in South Central Asia (45.8%) and sub-Saharan Africa (22.6%), cryptosporidiosis in sub-Saharan Africa (24.7%) and South-Central Asia (19.5%), cyclosporiasis in South East Asia (31.3%) and Central America (27.3%), and cystoisosporiasis in sub-Saharan Africa (62.5%). Cyclosporiasis cases were reported from countries of uncertain endemicity (e.g. Cambodia) or in countries with no previous evidence of this parasite (e.g. French Guiana). The time from symptom onset to presentation at a GeoSentinel site was the longest amongst travellers with giardiasis (median: 30 days). Over 14% of travellers with cryptosporidiosis were hospitalized. CONCLUSIONS: This analysis provides new insights into the epidemiology and clinical significance of four intestinal protozoa that can cause morbidity in international travellers. These data might help optimize pretravel advice and post-travel management of patients with travel-associated prolonged gastrointestinal illnesses. This analysis reinforces the importance of international travel-related surveillance to identify sentinel cases and areas where protozoal infections might be undetected or underreported.

Exploiting the CD200-CD200R immune checkpoint axis in multiple myeloma to enhance CAR T-cell therapy.

ABSTRACT: Patients with multiple myeloma (MM) treated with B-cell maturation antigen (BCMA)-specific chimeric antigen receptor (CAR) T cells usually relapse with BCMA+ disease, indicative of CAR T-cell suppression. CD200 is an immune checkpoint that is overexpressed on aberrant plasma cells (aPCs) in MM and is an independent negative prognostic factor for survival. However, CD200 is not present on MM cell lines, a potential limitation of current preclinical models. We engineered MM cell lines to express CD200 at levels equivalent to those found on aPCs in MM and show that these are sufficient to suppress clinical-stage CAR T-cells targeting BCMA or the Tn glycoform of mucin 1 (TnMUC1), costimulated by 4-1BB and CD2, respectively. To prevent CD200-mediated suppression of CAR T cells, we compared CRISPR-Cas9-mediated knockout of the CD200 receptor (CD200RKO), to coexpression of versions of the CD200 receptor that were nonsignaling, that is, dominant negative (CD200RDN), or that leveraged the CD200 signal to provide CD28 costimulation (CD200R-CD28 switch). We found that the CD200R-CD28 switch potently enhanced the polyfunctionality of CAR T cells, and improved cytotoxicity, proliferative capacity, CAR T-cell metabolism, and performance in a chronic antigen exposure assay. CD200RDN provided modest benefits, but surprisingly, the CD200RKO was detrimental to CAR T-cell activity, adversely affecting CAR T-cell metabolism. These patterns held up in murine xenograft models of plasmacytoma, and disseminated bone marrow predominant disease. Our findings underscore the importance of CD200-mediated immune suppression in CAR T-cell therapy of MM, and highlight a promising approach to enhance such therapies by leveraging CD200 expression on aPCs to provide costimulation via a CD200R-CD28 switch.

Severity of Mandibular Dysmorphology in Treacher Collins Syndrome for Stratification of Perioperative Airway Risk.

BACKGROUND: Patients with Treacher Collins syndrome (TCS) and attendant airway dysmorphology may be predisposed to airway complications in the perioperative period. However, limited data correlates severity of mandibular hypoplasia and airway status. This study aims to improve risk stratification for perioperative airway insufficiency in TCS by using a previously proposed mandibular severity index. METHODS: Patient demographics, perioperative airway status, difficulty of intubation, and Cormack Lehane grade were collected and compared using a TCS mandibular hypoplasia severity grading scale in patients with TCS treated between 2000 and 2022. RESULTS: Twenty-six patients underwent 222 procedures with institutional mandibular severity gradings as follows: 23% Grade I, 31% Grade II, 39% Grade III, 8% Grade IV. Our severity index was associated with intubation difficulty ( P <0.001) and difficult airway status ( P <0.001), with 72% of difficult airways found in grade III and grade IV patients. Mandibular retrusion and ramal hypoplasia subscores were positively correlated with measures of airway severity ( P <0.001), whereas the gonial angle was negatively correlated ( P <0.001). Age was negatively correlated with difficult visualization for endotracheal intubation ( P =0.02) but had no association with difficult airway status ( P =0.2). CONCLUSIONS: This study found a positive correlation between severity of maxillomandibular dysmorphology and perioperative airway difficulty in TCS patients. Our findings suggest that severely affected patients require heightened vigilance throughout life, as difficult airways may not completely resolve with aging. Given the risk of morbidity and mortality associated with airway complications, proper identification and preparation for challenging airways is critical for TCS patients.

Response-dependent point loss and response force as disrupting operations on behavioral resistance to change in humans.

Behavioral momentum theory (BMT) provides a theoretical and methodological framework for understanding how differentially maintained operant responding resists disruption. A common way to test operant resistance involves contingencies with suppressive effects, such as extinction or prefeeding. Other contingencies with known suppressive effects, such as response-cost procedures arranged as point-loss or increases in response force, remain untested as disruptive events within the BMT framework. In the present set of three experiments, responding of humans was maintained by point accumulation programmed according to a multiple variable-interval (VI) VI schedule with different reinforcement rates in either of two components. Subsequently, subtracting a point following each response (Experiment 1) or increasing the force required for the response to be registered (Experiments 2 and 3 decreased response rates, but responding was less disrupted in the component associated with the higher reinforcement rate. The point-loss contingency and increased response force similarly affected response rates by suppressing responding and human persistence, replicating previous findings with humans and nonhuman animals when other types of disruptive events (e.g., extinction and prefeeding) were investigated. The present findings moreover extend the generality of the effects of reinforcement rate on persistence, and thus BMT, extending the analysis of resistance to two well-known manipulations used to reduce responding in the experimental analysis of behavior.

LeFort III Versus Monobloc Frontofacial Advancement: A Comparative Analysis of Soft Tissue Changes.

INTRODUCTION: The LeFort III and monobloc are commonly used midface advancement procedures for patients with syndromic craniosynostosis with well characterized postoperative skeletal changes. However, the differential effects of these procedures on facial soft tissues are less understood. The purpose of this study was to critically analyze and compare the effects of these 2 procedures on the overlying soft tissues of the face. METHODS: Frontal and lateral preoperative and postoperative photographs of patients undergoing monobloc or LeFort III were retrospectively analyzed using ImageJ to measure soft tissue landmarks. Measurements included height of facial thirds, nasal length and width, intercanthal distance, and palpebral fissure height and width. Facial convexity was quantified by calculating the angle between sellion (radix), subnasale, and pogonion on lateral photographs. RESULTS: Twenty-five patients with an average age of 6.7 years (range 4.8-14.5) undergoing monobloc (n=12) and LeFort III (n=13) were identified retrospectively and analyzed preoperatively and 6.4±3.6 months postoperatively. Patients undergoing LeFort III had a greater average postoperative increase in facial convexity angle acuity (28.2°) than patients undergoing monobloc (17.8°, P =0.021). Patients in both groups experience postoperative increases in nasal width ( P <0.001) and decreases in palpebral fissure height ( P <0.001). CONCLUSIONS: Both subcranial LeFort III advancements and monobloc frontofacial advancements resulted in significant changes in the soft tissues. Patients undergoing LeFort III procedures achieved greater acuity of the facial convexity angle, likely because the nasion is not advanced with the LeFort III segment.