Analyzing the relative importance of habitat quantity and quality for boosting pollinator populations in agricultural landscapes.

To increase pollinator populations, international policy targets minimum levels of seminatural habitat cover, but it is unknown whether improving the quality of existing habitats could bring similar benefits without the need of reducing cropland area. Using data we collected in 26 Italian agricultural landscapes during the entire flying season, we explored the relative importance of habitat quantity (seminatural habitat cover) and quality (flower availability) on pollinator densities in seminatural habitats. We obtained transect-based counts and estimated the effect of habitat quantity (proportion of seminatural habitat) and quality (flower cover and richness) on wild bee and hoverfly densities. We used the relationships revealed in the data to simulate pollinator population sizes in landscapes with varying habitat quantity and quality. Wild bee densities were only related to flower availability, whereas hoverfly densities were additionally related to seminatural habitat cover. We found that in complex agricultural landscapes (above 15% seminatural habitat cover), improving habitat quality increased pollinator populations more effectively than increasing habitat quantity. However, increasing habitat quantity was by far the most effective approach for boosting pollinator populations in simple landscapes.

Análisis de la importancia relativa de la cantidad y calidad del hábitat para incrementar las poblaciones de polinizadores en los paisajes agrícolas Resumen Las políticas internacionales buscan que existan niveles mínimos de cobertura seminatural del hábitat para incrementar las poblaciones de polinizadores y se desconoce si mejorar la calidad de los hábitats existentes podría brindar beneficios similares sin tener que reducir el área de cultivo. Usamos datos recolectados en 26 paisajes agrícolas de Italia durante la temporada de vuelo para analizar la importancia relativa de la cantidad (cobertura de hábitat seminatural) y calidad (disponibilidad de flores) del hábitat para la densidad de polinizadores en los hábitats seminaturales. Obtuvimos conteos basados en transectos y estimamos el efecto de la cantidad (proporción del hábitat seminatural) y calidad (riqueza y cobertura de flores) del hábitat sobre la densidad de las abejas silvestres y los sírfidos. Usamos la relación revelada por los datos para simular el tamaño poblacional de los polinizadores en los paisajes con diferente calidad y cantidad de hábitat. La densidad de las abejas silvestres sólo se relacionó con la disponibilidad de flores cuando la densidad de sírfidos se relacionó con la cobertura del hábitat seminatural. Descubrimos que en los paisajes agrícolas complejos (por encima del 15% de cobertura de hábitat seminatural) cuya calidad mejoraba, las poblaciones de polinizadores incrementaban de manera más eficiente que cuando se mejoraba la cantidad. Sin embargo, incrementar la cantidad del hábitat fue por mucho la estrategia más efectiva para acrecentar las poblaciones de polinizadores en paisajes simples.

Morphological description of the digestive tract of the Amazonian Diving Lizard Uranoscodon superciliosus (Linnaeus, 1758) and its associations to the diet and foraging mode.

The study aimed to characterize the digestive tract of Uranoscodon superciliosus and its associations to the diet and foraging behavior already described for the species. Five lizards were captured in forest areas near the city of Manaus, Amazonas, Brazil. Tongue, oesophagus, stomach, small and large intestines fragments were collected, fixed, and processed for light microscopy. Hyaline cartilage was present in the center of the tongue, and the papillae from the apex and glands from the radix showed positive reaction to Alcian blue. The oesophagus presented a folded mucosa, covered by an epithelium with mucous and goblet cells positive to PAS and Alcian blue. There was presence of gastric glands in the cardic and fundic stomach regions, plus all the regions reacted positively to PAS. Fold and villi variations in both small and large intestine were noted, as well as the number and arrangement of goblet cells. Mucous and goblet cells from the small intestine were positively stained in PAS, while only the goblet cells were Alcian blue positive. These findings indicate that the Amazonian Diving Lizard's digestive tract organs, mainly the tongue and stomach, present morphologies associated to ambush-type foraging and a specific diet largely based on small invertebrates.

Glucagon-like peptide receptor agonists and risk for depression.

AIMS: Package labeling for weight loss formulations of semaglutide and liraglutide include a warning for suicidal thoughts and behaviors. The objective was to examine the association between glucagon-like peptide-1 receptor agonists (GLP-1RA) and incident depression. METHODS: This retrospective cohort study compared Veterans Health Administration patients initiated on a GLP-1RA versus a dipeptidyl peptidase-4 inhibitor (DPP-4i) between June 1, 2013 and June 30, 2020. The primary outcome was incident depression, defined as a new diagnosis of depression or new antidepressant prescription, within 1 year following drug initiation. Multivariable log-binomial regression was used to estimate relative risk, adjusted for confounding factors including patient demographics, comorbid conditions, and prior medication. RESULTS: Of 34,130 patients initiated on a GLP-1RA and 105,478 initiated on a DPP-4i, incident depression occurred in 7.7 % (n= 2263) and 6.3 % (n= 6602), respectively. After adjustment, the relative risk was 1.02 (95 % CI: 0.97 - 1.07), thus failing to demonstrate a significant increase in risk for incident depression following initiation of a GLP-1RA compared to DPP-4i. Relative risk estimates in all sensitivity analyses were also non-significant. CONCLUSIONS: This study did not demonstrate a significant increase in risk for incident depression following GLP-1RA initiation.

Corallus hortulanus testes histology: morphological and reproductive aspects.

In general snakes show differentiate anatomical, biological and behavioral particularities compared to other species. Basic information about the snakes anatomy, physiology and reproductive biology is scarce in several species, making the reproduction a challenge. Thus, the present work aims to evaluate morphological aspects of the Corallus hortulanus testes, correlating these findings with environmental factors and reproductive aspects. The testes of three specimens of Corallus hortulanus were cut to a thickness of 3µm in microtome, stained with 1% toluidine blue, photo documented and described. Seasonality was observed in the sperm production of Corallus hortulanus, with the presence of mature spermatozoa in the wettest and hottest periods of the year, as well as the largest testicular volume in these periods.

PGC-1α drives small cell neuroendocrine cancer progression towards an ASCL1-expressing subtype with increased mitochondrial capacity.

Adenocarcinomas from multiple tissues can converge to treatment-resistant small cell neuroendocrine (SCN) cancers comprised of ASCL1, POU2F3, NEUROD1, and YAP1 subtypes. We investigated how mitochondrial metabolism influences SCN cancer (SCNC) progression. Extensive bioinformatics analyses encompassing thousands of patient tumors and human cancer cell lines uncovered enhanced expression of PGC-1α, a potent regulator of mitochondrial oxidative phosphorylation (OXPHOS), across several SCNC types. PGC-1α correlated tightly with increased expression of the lineage marker ASCL1 through a positive feedback mechanism. Analyses using a human prostate tissue-based SCN transformation system showed that the ASCL1 subtype has heightened PGC-1α expression and OXPHOS activity. PGC-1α inhibition diminished OXPHOS, reduced SCNC cell proliferation, and blocked SCN prostate tumor formation. PGC-1α overexpression enhanced OXPHOS, tripled the SCN prostate tumor formation rate, and promoted commitment to the ASCL1 lineage. These findings reveal the metabolic heterogeneity among SCNC subtypes and identify PGC-1α-induced OXPHOS as a regulator of SCNC lineage plasticity.

Postnatal Consumption of Black Bean Powder Protects against Obesity and Dyslipidemia in Male Adult Rat Offspring from Obese Pregnancies.

The adverse influence of maternal obesity on offspring metabolic health throughout the life-course is a significant public health challenge with few effective interventions. We examined if black bean powder (BBP) supplementation to a high-calorie maternal pregnancy diet or a postnatal offspring diet could offer protection against the metabolic programming of metabolic disease risk in adult offspring. Female Sprague Dawley rats were randomly assigned to one of three diets (n = 10/group) for a 3-week pre-pregnancy period and throughout gestation and lactation: (i) a low-caloric control diet (CON); (ii) a high-caloric obesity-inducing diet (HC); or (iii) the HC diet with 20% black bean powder (HC-BBP). At weaning [postnatal day (PND) 21], one male pup from each dam was weaned onto the CON diet throughout the postnatal period until adulthood (PND120). In addition, a second male from the HC group only was weaned onto the CON diet supplemented with BBP (CON-BBP). Thus, based on the maternal diet exposure and offspring postnatal diet, four experimental adult offspring groups were compared: CON/CON, HC/CON, HC-BPP/CON, and HC/CON-BBP. On PND120, blood was collected for biochemical analysis (e.g., lipids, glycemic control endpoints, etc.), and livers were excised for lipid analysis (triglycerides [TG] and cholesterol) and the mRNA/protein expression of lipid-regulatory targets. Compared with the CON/CON group, adult offspring from the HC/CON group exhibited a higher (p < 0.05) body weight (BW) (682.88 ± 10.67 vs. 628.02 ± 16.61 g) and hepatic TG (29.55 ± 1.31 vs. 22.86 ± 1.85 mmol/g). Although maternal BBP supplementation (HC-BBP/CON) had little influence on metabolic outcomes, the consumption of BBP in the postnatal period (HC/CON-BBP) lowered hepatic TG and cholesterol compared with the other treatment groups. Reduced hepatic TG in the HC/CON-BBP was likely associated with lower postnatal BW gain (vs. HC/CON), lower mRNA and protein expression of hepatic Fasn (vs. HC/CON), and lower serum leptin concentration (vs. CON/CON and HC groups). Our results suggest that the postnatal consumption of a black-bean-powder-supplemented diet may protect male rat offspring against the programming of obesity and dyslipidemia associated with maternal obesity. Future work should investigate the bioactive fraction of BBP responsible for the observed effect.

Integrative metabolomics-genomics analysis identifies key networks in a stem cell-based model of schizophrenia.

Schizophrenia (SCZ) is a neuropsychiatric disorder, caused by a combination of genetic and environmental factors. The etiology behind the disorder remains elusive although it is hypothesized to be associated with the aberrant response to neurotransmitters, such as dopamine and glutamate. Therefore, investigating the link between dysregulated metabolites and distorted neurodevelopment holds promise to offer valuable insights into the underlying mechanism of this complex disorder. In this study, we aimed to explore a presumed correlation between the transcriptome and the metabolome in a SCZ model based on patient-derived induced pluripotent stem cells (iPSCs). For this, iPSCs were differentiated towards cortical neurons and samples were collected longitudinally at various developmental stages, reflecting neuroepithelial-like cells, radial glia, young and mature neurons. The samples were analyzed by both RNA-sequencing and targeted metabolomics and the two modalities were used to construct integrative networks in silico. This multi-omics analysis revealed significant perturbations in the polyamine and gamma-aminobutyric acid (GABA) biosynthetic pathways during rosette maturation in SCZ lines. We particularly observed the downregulation of the glutamate decarboxylase encoding genes GAD1 and GAD2, as well as their protein product GAD65/67 and their biochemical product GABA in SCZ samples. Inhibition of ornithine decarboxylase resulted in further decrease of GABA levels suggesting a compensatory activation of the ornithine/putrescine pathway as an alternative route for GABA production. These findings indicate an imbalance of cortical excitatory/inhibitory dynamics occurring during early neurodevelopmental stages in SCZ. Our study supports the hypothesis of disruption of inhibitory circuits to be causative for SCZ and establishes a novel in silico approach that enables for integrative correlation of metabolic and transcriptomic data of psychiatric disease models.

Carotid wave analysis in young adults with a history of adolescent anorexia nervosa: a case control study.

BACKGROUND: Anorexia nervosa (AN) is associated with abnormalities that may increase the risk of future cardiovascular disease. This study assessed the cardiovascular health of individuals who recovered from AN during adolescence by conducting wave power analysis. METHODS: Former AN patients discharged from the Royal Children's and Monash Children's Hospitals (N = 17) in Melbourne, Australia underwent ultrasound imaging of the right carotid artery. Wave power analysis was conducted to assess biomechanical interactions of the cardiovascular system. Patient measures were compared to healthy controls (N = 51). RESULTS: Eighty-eight percent of the former AN patients and controls were female, aged approximately 25 years, with a healthy body mass index. Mean carotid flow and pulsatility index were not different between groups. Carotid arterial strain and distensibility were lower, and the wave speed and beta stiffness index higher in the former AN patients. Characteristic impedance was not different nor were the forward and backward wave amplitudes. However, wave reflection indices (ratios of backward-to-forward compression wave area, and wave-related effect on pressure and hydraulic power) were 12-18% lower in the former AN patients (p < 0.05). CONCLUSIONS: Increased carotid artery stiffness and reduced wave reflection are evident in young adults who recovered from adolescent AN. This may relate to an adaptive process that helps to maintain or restore flow and characteristic impedance despite increased vessel stiffness, with this warranting future investigation.

Anorexia nervosa (AN) is an eating disorder which may cause permanent changes in the heart and blood vessels. Blood flow properties can provide information on the health of a patient's heart and blood vessels. In this study of young adults who recovered from adolescent AN, blood flow analysis revealed altered properties compared to controls who had never experienced an eating disorder. These alterations may help to maintain or restore blood flow despite unhealthy changes in the blood vessels themselves. Further investigation is needed to better understand how the heart and blood vessels change during and after AN to guide treatments and ongoing care. Regular assessment of the heart and blood vessels after AN recovery could identify and monitor possible health risks early.

Antibacterial and Antiviral Properties of Chenopodin-Derived Synthetic Peptides.

Antimicrobial peptides have been developed based on plant-derived molecular scaffolds for the treatment of infectious diseases. Chenopodin is an abundant seed storage protein in quinoa, an Andean plant with high nutritional and therapeutic properties. Here, we used computer- and physicochemical-based strategies and designed four peptides derived from the primary structure of Chenopodin. Two peptides reproduce natural fragments of 14 amino acids from Chenopodin, named Chen1 and Chen2, and two engineered peptides of the same length were designed based on the Chen1 sequence. The two amino acids of Chen1 containing amide side chains were replaced by arginine (ChenR) or tryptophan (ChenW) to generate engineered cationic and hydrophobic peptides. The evaluation of these 14-mer peptides on Staphylococcus aureus and Escherichia coli showed that Chen1 does not have antibacterial activity up to 512 µM against these strains, while other peptides exhibited antibacterial effects at lower concentrations. The chemical substitutions of glutamine and asparagine by amino acids with cationic or aromatic side chains significantly favoured their antibacterial effects. These peptides did not show significant hemolytic activity. The fluorescence microscopy analysis highlighted the membranolytic nature of Chenopodin-derived peptides. Using molecular dynamic simulations, we found that a pore is formed when multiple peptides are assembled in the membrane. Whereas, some of them form secondary structures when interacting with the membrane, allowing water translocations during the simulations. Finally, Chen2 and ChenR significantly reduced SARS-CoV-2 infection. These findings demonstrate that Chenopodin is a highly useful template for the design, engineering, and manufacturing of non-toxic, antibacterial, and antiviral peptides.

Routine outcomes and evaluation of an 8-week outpatient multidisciplinary rehabilitative therapy program for functional neurological disorder.

OBJECTIVES: We report routinely collected outcome data from an 8-week outpatient rehabilitative therapy program. The aims of the intervention were to (1) reduce symptom severity and (2) improve functional mobility in adults with functional neurological disorder (FND). METHODS: The program delivered individual physiotherapy, cognitive behavioral therapy (CBT) and self-management sessions, group physiotherapy, and psychoeducation. Outcome measures included the Beck Anxiety Inventory (BAI), Beck Depression Inventory (BDI-II), Work and Social Adjustment Scale (WSAS), 10-Meter Walk Test (10MWT), Timed Up and Go (TUG), and Berg Balance Scale (BBS). Data were analyzed retrospectively in accordance with routine service evaluation. Wilcoxon signed-rank tests assessed changes in outcomes between weeks 1 and 8 for all patients completing treatment (n = 45). For patients who attended the 3-month follow-up (n = 31), Friedman's ANOVA assessed overall change in outcomes over time. Post hoc Wilcoxon signed-rank tests compared pairs of time-points (Weeks 1, 8, and 3-month follow-up). RESULTS: Analyses of patients completing the program revealed significant improvements in scores between week 1 and week 8. Excluding the BBS, there were statistically significant improvements in all outcomes between weeks 1 and 8 and between weeks 1 and 3-month follow-up. DISCUSSION: This outpatient therapy program provided effective treatment for FND. Patients reported reduced anxiety, depression, and functional impairment, as well as improved performance on most physiotherapy measures.

Relationship between brain structural network integrity and emotional symptoms in youth with perinatally-acquired HIV.

Perinatally acquired HIV infection (PHIV) currently affects approximately 1.7 million children worldwide. Youth with PHIV (YPHIV) are at increased risk for emotional and behavioral symptoms, yet few studies have examined relationships between these symptoms and brain structure. Previous neuroimaging studies in YPHIV report alterations within the salience network (SN), cognitive control network (CCN), and default mode network (DMN). These areas have been associated with social and emotional processing, emotion regulation, and executive function. We examined structural brain network integrity from MRI using morphometric similarity networks and graph theoretical measures of segregation (transitivity), resilience (assortativity), and integration (global efficiency). We examined brain network integrity of 40 YPHIV compared to 214 youths without HIV exposure or infection. Amongst YPHIV, we related structural brain network metrics to the Emotional Symptoms Index of the Behavioral Assessment System for Children, 2nd edition. We also examined the relationship of inflammatory biomarkers in YPHIV to brain network integrity. YPHIV had significantly lower global efficiency in the SN, DMN, and the whole brain network compared to controls. YPHIV also demonstrated lower assortativity or resilience (i.e., network robustness) compared to controls in the DMN and whole brain network. Further, higher emotional symptom score was associated with higher global efficiency in the SN and lower global efficiency in the DMN, signaling more emotional challenges. A significant association was also found between several inflammatory and cardiac markers with structural network integrity. These findings suggest an impact of HIV on developing brain networks, and potential dysfunction of the SN and DMN in relation to network efficiency.

Generation of a Dcx-CreERT2 knock-in mouse for genetic manipulation of newborn neurons.

A wide variety of CreERT2 driver lines are available for genetic manipulation of adult-born neurons in the mouse brain. These tools have been instrumental in studying fate potential, migration, circuit integration, and morphology of the stem cells supporting lifelong neurogenesis. Despite a wealth of tools, genetic manipulation of adult-born neurons for circuit and behavioral studies has been limited by poor specificity of many driver lines targeting early progenitor cells and by the inaccessibility of lines selective for later stages of neuronal maturation. We sought to address these limitations by creating a new CreERT2 driver line targeted to the endogenous mouse doublecortin locus as a marker of fate-specified neuroblasts and immature neurons. Our new model places a T2A-CreERT2 cassette immediately downstream of the Dcx coding sequence on the X chromosome, allowing expression of both Dcx and CreERT2 proteins in the endogenous spatiotemporal pattern for this gene. We demonstrate that the new mouse line drives expression of a Cre-dependent reporter throughout the brain in neonatal mice and in known neurogenic niches of adult animals. The line has been deposited with the Jackson Laboratory and should provide an accessible tool for studies targeting fate-restricted neuronal precursors.

Catch the Calcium: T-Cell Histiocyte-Rich B-Cell Lymphoma Presenting as Hypercalcemia.

T-cell/histiocyte-rich large B-cell lymphoma (THRLBCL) is an extremely rare and aggressive subtype of diffuse large B-cell lymphoma (DLBCL) that typically presents in middle-aged patients and carries a poor prognosis. Hypercalcemia presenting as the initial manifestation of the disease is rare, with only one other case reported in the literature. We report a case of a 90-year-old male who presented with progressive lethargy and unintentional weight loss. Initial workup showed elevated serum calcium of 14.6 mg/dL, corrected for albumin, and creatinine of 1.51 mg/dL. He had a suppressed iPTH of 6.3 pg/mL and normal PTHrP (13 pg/mL). Computed tomography (CT) scan of the abdomen and pelvis was performed to rule out underlying malignancy, which showed splenomegaly and enlarged retrocrural and porta hepatis lymph nodes. Bone marrow biopsy was performed to evaluate for hematological malignancy, which revealed findings diagnostic of THRLBCL. While rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) is one of the mainstay therapies for DLBCL and has been shown to have comparable outcomes in THRLBCL, there are documented concerns with its toxicity profile limiting the ability of older patients (60 years and older) to complete therapy. Our patient was treated with R-mini-CHOP, which is much better tolerated in this patient demographic. R-mini-CHOP features decreased doses of cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) with the conventional dose of rituximab. This case discusses a rare subtype of non-Hodgkin lymphoma presenting with a unique manifestation of hypercalcemia. We highlight the importance of thorough investigation for causes of hypercalcemia as well as the efficacy and tolerability of R-mini-CHOP in this elderly patient demographic.

The impact of caregiver mental health on child prosocial behavior: A longitudinal analysis of children and caregivers in KwaZulu-Natal, South Africa.

BACKGROUND: Prosocial behavior has positive social, cognitive, and physical health effects on the individual exhibiting the behavior as well as on society as a whole, and is integral to overall mental and physical wellbeing. The development of prosocial behavior is rooted in early childhood and learned through observation. As such, those spending time with children, especially their caregiver, play a critical role in their prosocial development. The current study investigates the impact of caregiver mental health on the prosocial development of young children over time. METHODS: This paper presents a secondary analysis of child prosocial development in the Asenze Study, a longitudinal, population-based cohort study based in KwaZulu-Natal, South Africa. Children were followed-up over time from an average age of five to seven years along with their caregivers. Linear GEE regression analysis was used to assess whether a change in presence of a mental health disorder in a caregiver during this 2-year interval (using the Client Diagnostic Questionnaire) impacted the development of their child's prosocial behavior (using the Strengths and Difficulties Questionnaire). RESULTS: After adjusting for early child-care, child HIV status, SDQ child prosocial subscale, SDQ total difficulties score, and household order score (CHAOS), children whose caregivers acquired a mental health disorder had a significantly smaller increase in prosocial behavioral development compared to children whose caregivers never had a mental health disorder. CONCLUSIONS: Identifying contextually relevant modifiable factors such as this will help stimulate the development of interventions to promote prosocial development in childhood.

Sex differences in brain protein expression and disease.

Most complex human traits differ by sex, but we have limited insight into the underlying mechanisms. Here, we investigated the influence of biological sex on protein expression and its genetic regulation in 1,277 human brain proteomes. We found that 13.2% (1,354) of brain proteins had sex-differentiated abundance and 1.5% (150) of proteins had sex-biased protein quantitative trait loci (sb-pQTLs). Among genes with sex-biased expression, we found 67% concordance between sex-differentiated protein and transcript levels; however, sex effects on the genetic regulation of expression were more evident at the protein level. Considering 24 psychiatric, neurologic and brain morphologic traits, we found that an average of 25% of their putatively causal genes had sex-differentiated protein abundance and 12 putatively causal proteins had sb-pQTLs. Furthermore, integrating sex-specific pQTLs with sex-stratified genome-wide association studies of six psychiatric and neurologic conditions, we uncovered another 23 proteins contributing to these traits in one sex but not the other. Together, these findings begin to provide insights into mechanisms underlying sex differences in brain protein expression and disease.

Addressing the Burden and Management Strategies for Disparities and Inequities Among Liver Transplant Professionals: The ILTS Experience.

Medical professional environments are becoming increasingly multicultural, international, and diverse in terms of its specialists. Many transplant professionals face challenges related to gender, sexual orientation or racial background in their work environment or experience inequities involving access to leadership positions, professional promotion, and compensation. These circumstances not infrequently become a major source of work-related stress and burnout for these disadvantaged, under-represented transplant professionals. In this review, we aim to 1) discuss the current perceptions regarding disparities among liver transplant providers 2) outline the burden and impact of disparities and inequities in the liver transplant workforce 3) propose potential solutions and role of professional societies to mitigate inequities and maximize inclusion within the transplant community.

Carnitine o-octanoyltransferase is a p53 target that promotes oxidative metabolism and cell survival following nutrient starvation.

Whereas it is known that p53 broadly regulates cell metabolism, the specific activities that mediate this regulation remain partially understood. Here, we identified carnitine o-octanoyltransferase (CROT) as a p53 transactivation target that is upregulated by cellular stresses in a p53-dependent manner. CROT is a peroxisomal enzyme catalyzing very long-chain fatty acids conversion to medium chain fatty acids that can be absorbed by mitochondria during ß-oxidation. p53 induces CROT transcription through binding to consensus response elements in the 5'-UTR of CROT mRNA. Overexpression of WT but not enzymatically inactive mutant CROT promotes mitochondrial oxidative respiration, while downregulation of CROT inhibits mitochondrial oxidative respiration. Nutrient depletion induces p53-dependent CROT expression that facilitates cell growth and survival; in contrast, cells deficient in CROT have blunted cell growth and reduced survival during nutrient depletion. Together, these data are consistent with a model where p53-regulated CROT expression allows cells to be more efficiently utilizing stored very long-chain fatty acids to survive nutrient depletion stresses.

Living without pain. Case series of patients with hereditary sensory and autonomic neuropathies in a Canadian tertiary care centre.

Background: Hereditary sensory and autonomic neuropathies (HSANs) are a group of heterogeneous genetic disorders presenting predominantly with sensory and autonomic dysfunction. They are a diverse group of diseases of the peripheral nervous system characterized by profound distal sensory loss and various autonomic and motor disturbances. Objectives: The primary objective of this study was to describe the clinical presentation of children with HSAN to paediatricians. We present clinical features and genetic etiology of patients with HSAN followed in a Canadian tertiary paediatric centre, including suggestions for their monitoring, management, and long-term follow-up. Methods: A retrospective chart review of all patients with HSAN followed from the years 2000 through 2021 was performed. Collected data consisted of patients' demographics, clinical characteristics, imaging, and management. Results: Eight patients were included. The average age at diagnosis was 3.19 ±â€…2.83 years. Insensitivity to pain (100%), dysautonomia (100%), global development delay (87.5%), emesis (62.5%), and self-injury (62.5%) were the most prevalent manifestations of HSAN. The most common co-morbidities were gastroesophageal reflux disease (50%), obstructive sleep apnea (37.5%), attention-deficit hyperactivity disorder (37.5%), and iron deficiency (37.5%). Management was multi-disciplinary, involving neurologists, orthopeds, developmental paediatricians, sleep specialists, and psychiatrists. Conclusion: HSANs are a diverse group of diseases, characterized by profound distal sensory loss, acral mutilations, and variable autonomic disturbances. It is important to recognize the diagnosis in the paediatrician's office in order to set up surveillance and prevent complications.

The diverse effects of pathogenic point mutations on ion channel activity of a gain-of-function polycystin-2.

Autosomal dominant polycystic kidney disease is caused by mutations in PKD1 or PKD2 genes. The latter encodes polycystin-2 (PC2, also known as TRPP2), a member of the transient receptor potential ion channel family. Despite most pathogenic mutations in PKD2 being truncation variants, there are also many point mutations, which cause small changes in protein sequences but dramatic changes in the in vivo function of PC2. How these mutations affect PC2 ion channel function is largely unknown. In this study, we systematically tested the effects of 31 point mutations on the ion channel activity of a gain-of-function PC2 mutant, PC2_F604P, expressed in Xenopus oocytes. The results show that all mutations in the transmembrane domains and channel pore region, and most mutations in the extracellular tetragonal opening for polycystins domain, are critical for PC2_F604P channel function. In contrast, the other mutations in the tetragonal opening for polycystins domain and most mutations in the C-terminal tail cause mild or no effects on channel function as assessed in Xenopus oocytes. To understand the mechanism of these effects, we have discussed possible conformational consequences of these mutations based on the cryo-EM structures of PC2. The results help gain insight into the structure and function of the PC2 ion channel and the molecular mechanism of pathogenesis caused by these mutations.