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1.
Materials (Basel) ; 17(9)2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38730781

RESUMEN

In the present work, the influence of a corrosive environment and temperature on the corrosion resistance properties of duplex stainless steel S31803 was evaluated. The corrosive process was carried out using solutions of 1.5% HCl (m/m) and 6% FeCl3 (m/m), at temperatures of 25 and 50 °C. The microstructure of UNS S31803 duplex stainless steel is composed of two phases, ferrite and austenite, oriented in the rolling direction, containing a ferrite percentage of 46.2% in the rolling direction and 56.1% in the normal direction. Samples, when subjected to corrosive media and temperature, tend to decrease their mechanical property values. It was observed, in both corrosive media, that with increasing test temperature, there is an increase in the corrosion rate, both uniform and pitting. The sample in HCl solution obtained a uniform corrosion rate of 0.85% at 25 °C and 0.92% at 50 °C and pitting rates of 0.77% and 1.47% at the same temperatures, respectively. When tested in FeCl3 solution, it obtained uniform corrosion of 0.0006% and 0.93% and pitting of 0.53% and 18.5%, at the same temperatures. A reduction in dissolution potentials is also noted, thus characterizing greater corrosion in the samples with increasing temperature.

2.
J Med Primatol ; 53(3): e12700, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38706108

RESUMEN

A 40-year old female chimpanzee (Pan troglodytes) developed hyporexia, weight loss, followed by progressive and complete blindness. Tomography demonstrated an intracranial mass in the rostroventral brain involving the optic chiasm, with a presumptive diagnosis of neoplasm. However, histopathology revealed a granulomatous meningoencephalitis, and tissue samples tested positive for Mycobacterium tuberculosis.


Asunto(s)
Enfermedades del Simio Antropoideo , Ceguera , Meningoencefalitis , Mycobacterium tuberculosis , Pan troglodytes , Animales , Femenino , Enfermedades del Simio Antropoideo/diagnóstico , Enfermedades del Simio Antropoideo/microbiología , Enfermedades del Simio Antropoideo/patología , Mycobacterium tuberculosis/aislamiento & purificación , Ceguera/veterinaria , Ceguera/etiología , Ceguera/microbiología , Ceguera/diagnóstico , Meningoencefalitis/veterinaria , Meningoencefalitis/microbiología , Meningoencefalitis/diagnóstico , Granuloma/veterinaria , Granuloma/microbiología , Granuloma/patología , Granuloma/diagnóstico , Tuberculosis/veterinaria , Tuberculosis/diagnóstico , Tuberculosis/complicaciones
3.
PLoS Biol ; 22(4): e3002583, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38598454

RESUMEN

Endosymbiotic relationships are pervasive across diverse taxa of life, offering key avenues for eco-evolutionary dynamics. Although a variety of experimental and empirical frameworks have shed light on critical aspects of endosymbiosis, theoretical frameworks (mathematical models) are especially well-suited for certain tasks. Mathematical models can integrate multiple factors to determine the net outcome of endosymbiotic relationships, identify broad patterns that connect endosymbioses with other systems, simplify biological complexity, generate hypotheses for underlying mechanisms, evaluate different hypotheses, identify constraints that limit certain biological interactions, and open new lines of inquiry. This Essay highlights the utility of mathematical models in endosymbiosis research, particularly in generating relevant hypotheses. Despite their limitations, mathematical models can be used to address known unknowns and discover unknown unknowns.


Asunto(s)
Modelos Teóricos , Simbiosis , Evolución Biológica
4.
Artículo en Inglés | MEDLINE | ID: mdl-38653363

RESUMEN

A functional lateralization has been reported in control of emotional responses by the medial prefrontal cortex (mPFC). However, a hemisphere asymmetry in involvement of the mPFC in expression of fear conditioning responses has never been reported. Therefore, we investigated whether control by mPFC of freezing and cardiovascular responses during re-exposure to an aversively conditioned context is lateralized. For this, rats had guide cannulas directed to the mPFC implanted bilaterally or unilaterally in the right or left hemispheres. Vehicle or the non-selective synaptic inhibitor CoCl2 was microinjected into the mPFC 10 min before re-exposure to a chamber where the animals had previously received footshocks. A catheter was implanted into the femoral artery before the fear retrieval test for cardiovascular recordings. We observed that bilateral microinjection of CoCl2 into the mPFC reduced both the freezing behavior (enhancing locomotion and rearing) and arterial pressure and heart rate increases during re-exposure to the aversively conditioned context. Unilateral microinjection of CoCl2 into the right hemisphere of the mPFC also decreased the freezing behavior (enhancing locomotion and rearing), but without affecting the cardiovascular changes. Conversely, unilateral synaptic inhibition in the left mPFC did not affect either behavioral or cardiovascular responses during fear retrieval test. Taken together, these results suggest that the right hemisphere of the mPFC is necessary and sufficient for expression of freezing behavior to contextual fear conditioning. However, the control of cardiovascular responses and freezing behavior during fear retrieval test is somehow dissociated in the mPFC, being the former bilaterally processed.

5.
Ecotoxicology ; 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38602608

RESUMEN

The annual killifish Austrolebias charrua is an endangered species, endemic to the southern region of South America, which inhabits temporary ponds that emerges in the rainy season. The main anthropogenic threat driving the extinction of A. charrua stems from extensive agriculture, primarily due to the widrespread use of glyphosate-based herbicides near their habitats. Annual killifishes have been used as models for ecotoxicological studies but, up to now, there are no studies about reference genes in any Austrolebias species. This represents an obstacle to the use of qPCR-based technologies, the standard method for gene expression quantification. The present study aimed to select and validate potential reference genes for qPCR normalization in the annual killifish Austrolebias charrua considering different tissues, gender and environmental conditions. The candidate reference genes 18 s, actb, gapdh, ef1a, shox, eif3g, and the control gene atp1a1 were evaluated in male and female individuals in three different tissues (brain, liver, and gills) under two experimental conditions (control and acute exposition to Roundup Transorb®). The collected tissues were submitted to RNA extraction, followed by cDNA synthesis, cloning, sequencing, and qPCR. Overall, 18 s was the most stable reference gene, and 18 s and ef1a were the most stable combination. Otherwise, considering all variables, gapdh and shox were the least stable candidate genes. Foremost, suitable reference genes were validated in A. charrua, facilitating accurate mRNA quantification in this species, which might be useful for developing molecular tools of ecotoxicological assessment based on gene expression analysis for environmental monitoring of annual killifish.

6.
BMC Health Serv Res ; 24(1): 437, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38589863

RESUMEN

BACKGROUND: Health professionals in home care work in interprofessional teams. Yet most training in decision support assumes a one-on-one relationship with patients. We assessed the impact of an in-person training session in interprofessional shared decision-making (IP-SDM) on home care professionals' intention to adopt this approach. METHODS: We conducted a secondary analysis of a cluster stepped-wedge trial using a before-and-after study design. We collected data among home care professionals from November 2016 to February 2018 in 9 health and social services centers in Quebec, Canada. The intervention was an in-person IP-SDM training session. Intention to engage in IP-SDM pre- and post-session (dependent variable) was compared using a continuing professional development evaluation scale (CPD-Reaction) informed by the Godin's Integrated Behavioral Model for health professionals. We also assessed socio-demographic and psychosocial variables (beliefs about capabilities, beliefs about consequences, social influence and moral norm). We performed bivariate and multivariate analysis to identify factors influencing post-intervention intention. We used the STROBE reporting guidelines for observational studies to report our results. RESULTS: Of 134 respondents who provided complete pairs of questionnaires (pre- and post-), most were female (90.9%), mean age was 42 (± 9.3) years and 66.9% were social workers. Mean intention scores decreased from 5.84 (± 1.19) to 5.54 (± 1.35) (Mean difference = -0.30 ± 1.16; p = 0.02). Factors associated with higher intention post-intervention were social influence (ß = 0.34, p = 0.01) and belief about capabilities (ß = 0.49, p < 0.01). CONCLUSION: After in-person IP-SDM training, healthcare professionals' intention to engage in IP-SDM decreased. However, the scope of this decrease is probably not clinically significant. Due to their association with intention, beliefs about capabilities, which translate into having a sense of self-competency in the new clinical behavior, and social influences, which translate into what important others think one should be doing, could be targets for future research aiming to implement IP-SDM in home care settings.


Asunto(s)
Servicios de Atención de Salud a Domicilio , Intención , Humanos , Femenino , Adulto , Masculino , Toma de Decisiones , Relaciones Interprofesionales , Toma de Decisiones Conjunta , Participación del Paciente/métodos
7.
Exp Parasitol ; 261: 108750, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38614222

RESUMEN

Amoebiasis is a disease caused by Entamoeba histolytica, affecting the large intestine of humans and occasionally leading to extra-intestinal lesions. Entamoeba dispar is another amoeba species considered commensal, although it has been identified in patients presenting with dysenteric and nondysenteric colitis, as well as amoebic liver abscess. Amoebic virulence factors are essential for the invasion and development of lesions. There is evidence showing that the association of enterobacteria with trophozoites contributes to increased gene expression of amoebic virulence factors. Enteropathogenic Escherichia coli is an important bacterium causing diarrhea, with high incidence rates in the world population, allowing it to interact with Entamoeba sp. in the same host. In this context, this study aims to evaluate the influence of enteropathogenic Escherichia coli on ACFN and ADO Entamoeba dispar strains by quantifying the gene expression of virulence factors, including galactose/N-acetyl-D-galactosamine-binding lectin, cysteine proteinase 2, and amoebapores A and C. Additionally, the study assesses the progression and morphological aspect of amoebic liver abscess and the profile of inflammatory cells. Our results demonstrated that the interaction between EPEC and ACFN Entamoeba dispar strains was able to increase the gene expression of virulence factors, as well as the lesion area and the activity of the inflammatory infiltrate. However, the association with the ADO strain did not influence the gene expression of virulence factors. Together, our findings indicate that the interaction between EPEC, ACFN, and ADO Entamoeba dispar strains resulted in differences in vitro and in vivo gene expression of Gal/GalNAc-binding lectin and CP2, in enzymatic activities of MPO, NAG, and EPO, and consequently, in the ability to cause lesions.


Asunto(s)
Entamoeba , Escherichia coli Enteropatógena , Factores de Virulencia , Escherichia coli Enteropatógena/patogenicidad , Escherichia coli Enteropatógena/genética , Entamoeba/patogenicidad , Entamoeba/genética , Entamoeba/fisiología , Factores de Virulencia/genética , Virulencia , Animales , Ratones , Absceso Hepático Amebiano/parasitología , Entamebiasis/parasitología , Humanos , Expresión Génica
8.
Rev Gaucha Enferm ; 45: e20230059, 2024.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-38655928

RESUMEN

OBJECTIVE: To identify the factors associated with the omission of nursing care and patient safety climate. METHOD: A cross-sectional study developed at a university hospital in the Brazilian Center-West, between September and December 2022. The MISSCARE-Brazil and the Safety Attitudes Questionnaire were applied to a convenience sample of 164 nursing professionals. RESULTS: The most omitted care was walking three times a day or as prescribed (66.5%). The overall score of the Safety Attitudes Questionnaire was 63,8 (SD: 12,6). The level of satisfaction (p<0.018) and the perception of professional adequacy (p<0.018) were associated with the omission of nursing care and the patient safety climate. CONCLUSION: The study showed a high prevalence of omission of care and unfavorable perception of the patient safety climate, mainly associated with professional adequacy for work performance.


Asunto(s)
Seguridad del Paciente , Humanos , Estudios Transversales , Femenino , Masculino , Adulto , Brasil , Persona de Mediana Edad , Actitud del Personal de Salud , Cultura Organizacional , Encuestas y Cuestionarios , Atención de Enfermería , Adulto Joven , Personal de Enfermería en Hospital/psicología , Hospitales Universitarios
9.
Psychopharmacology (Berl) ; 241(6): 1161-1176, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38347153

RESUMEN

RATIONALE: Chronic stress exposure disrupts the medial prefrontal cortex's (mPFC) ability to regulate impulses, leading to the loss of control over alcohol drinking in rodents, emphasizing the critical role of this forebrain area in regulating alcohol consumption. Moreover, chronic stress exposure causes lateralization of mPFC functions with volumetric and functional changes, resulting in hyperactivity in the right hemisphere and functional decrease in the left. OBJECTIVES: This study investigated the inhibitory role of the left prelimbic cortex (LPrL) on ethanol consumption induced by chronic social defeat stress (SDS) in male mice and to examine if inactivation of the LPrL causes disinhibition of the right mPFC, leading to an increase in ethanol consumption. We also investigated the role of lateralization and neurochemical alterations in the mPFC related to ethanol consumption induced by chronic SDS. To this end, we examined the activation patterns of ΔFosB, VGLUT2, and GAD67 in the left and right mPFC. RESULTS: Temporarily blocking the LPrL or right PrL (RPrL) cortices during acute SDS did not affect male mice's voluntary ethanol consumption in male mice. When each cortex was blocked in mice previously exposed to chronic SDS, ethanol consumption also remained unaffected. However, male mice with LPrL lesions during chronic SDS showed an increase in voluntary ethanol consumption, which was associated with enhanced ΔFosB/VGLUT2-positive neurons within the RPrL cortex. CONCLUSIONS: The results suggest that the LPrL may play a role in inhibiting ethanol consumption induced by chronic SDS, while the RPrL may be involved in the disinhibition of ethanol consumption.


Asunto(s)
Consumo de Bebidas Alcohólicas , Corteza Prefrontal , Derrota Social , Estrés Psicológico , Animales , Masculino , Estrés Psicológico/metabolismo , Consumo de Bebidas Alcohólicas/psicología , Ratones , Corteza Prefrontal/metabolismo , Corteza Prefrontal/efectos de los fármacos , Ratones Endogámicos C57BL , Etanol/administración & dosificación , Etanol/farmacología , Lateralidad Funcional/efectos de los fármacos , Enfermedad Crónica
10.
JCI Insight ; 9(6)2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38349753

RESUMEN

Glucose homeostasis is achieved via complex interactions between the endocrine pancreas and other peripheral tissues and glucoregulatory neurocircuits in the brain that remain incompletely defined. Within the brain, neurons in the hypothalamus appear to play a particularly important role. Consistent with this notion, we report evidence that (pro)renin receptor (PRR) signaling within a subset of tyrosine hydroxylase (TH) neurons located in the hypothalamic paraventricular nucleus (PVNTH neurons) is a physiological determinant of the defended blood glucose level. Specifically, we demonstrate that PRR deletion from PVNTH neurons restores normal glucose homeostasis in mice with diet-induced obesity (DIO). Conversely, chemogenetic inhibition of PVNTH neurons mimics the deleterious effect of DIO on glucose. Combined with our finding that PRR activation inhibits PVNTH neurons, these findings suggest that, in mice, (a) PVNTH neurons play a physiological role in glucose homeostasis, (b) PRR activation impairs glucose homeostasis by inhibiting these neurons, and (c) this mechanism plays a causal role in obesity-associated metabolic impairment.


Asunto(s)
Glucosa , Receptor de Prorenina , Animales , Ratones , Glucosa/metabolismo , Hipotálamo/metabolismo , Neuronas/metabolismo , Obesidad/complicaciones , Obesidad/metabolismo , Tirosina 3-Monooxigenasa/metabolismo
11.
Mem Inst Oswaldo Cruz ; 119: e230173, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38324879

RESUMEN

BACKGROUND: The incidence of visceral leishmaniasis (VL) has increased in the Southern region of Brazil in recent years, especially in the State of Paraná. New species have been suggested with potential to act as vector in VL endemic areas. OBJECTIVES: Identify the Leishmania species in sand fly specimens collected from 2016 to 2018 in the municipality of Itaperuçu, Vale do Ribeira, Paraná, Brazil. METHODS: Light traps were used for collections and for the analysis of sand fly were used the multiplex polymerase chain reaction (PCR) methodology and subsequent sequencing. FINDINGS: Among the collected specimens, 88.62% were attributed to the species Nyssomyia neivai, which were grouped into 176 pools. Three positive pools were detected: two with Leishmania (Viannia) braziliensis and one with L. (Leishmania) infantum. The positivity rate for the parasite was 0.25% based on the presence of at least one infected insect in the pool. MAIN CONCLUSIONS: The detection of L. infantum in Ny. neivai draws attention due to its abundance and anthropophily in the State of Paraná. Moreover, this finding is considered as an alert and suggests that the vector competence of Ny. neivai and the criteria for its incrimination should be carried out, given its wide distribution in southern of Brazil.


Asunto(s)
Leishmania braziliensis , Leishmania infantum , Leishmaniasis Visceral , Phlebotomus , Psychodidae , Animales , Leishmania infantum/genética , Brasil/epidemiología , Psychodidae/parasitología , Leishmania braziliensis/genética , ADN
12.
Front Neurol ; 15: 1325222, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38343710

RESUMEN

Introduction: Tubular aggregates (TA) are skeletal muscle structures that arise from the progressive accumulation of sarcoplasmic reticulum proteins. Cytoplasmic aggregates in muscle fibers have already been observed in mice and humans, mainly during aging and muscle disease processes. However, the effects of muscle regeneration on TA formation have not yet been reported. This study aimed to investigate the relationship between degeneration/regeneration and TA in aged murine models. We investigated the presence and quantity of TA in old males from two murine models with intense muscle degeneration and regeneration. Methods: One murine lineage was a Dmdmdx model of Duchenne muscular dystrophy (n = 6). In the other model, muscle damage was induced by electroporation in C57BL/6J wild-type mice, and analyzed after 5, 15, and 30 days post-electroporation (dpe; n = 15). Regeneration was evaluated based on the quantity of developmental myosin heavy chain (dMyHC)-positive fibers. Results: The frequency of fibers containing TA was higher in aged C57BL/6J (26 ± 8.3%) than in old dystrophic Dmdmdx mice (2.4 ± 2%). Comparing the data from induced degeneration/regeneration in normal mice revealed a reduced proportion of TA-containing fibers after 5 and 30 dpe. Normal aged muscle was able to regenerate and form dMyHC+ fibers, mainly at 5 dpe (0.1 ± 0.1 vs. 16.5 ± 2.6%). However, there was no difference in force or resistance between normal and 30 dpe animals, except for the measurements by the Actimeter device, which showed the worst parameters in the second group. Discussion: Our results suggest that TA also forms in the Dmdmdx muscle but in smaller amounts. The intense degeneration and regeneration of the old dystrophic model resulted in the generation of new muscle fibers with a lower quantity of TA. Data from electroporated wild-type mice support the idea that muscle regeneration leads to a reduction in the amount of TA. We suggest that TA accumulates in muscle fibers throughout physiological aging and that regeneration leads to the formation of new fibers without these structures. In addition, these new fibers do not confer functional benefits to the muscle.

13.
Addict Biol ; 29(2): e13366, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38380710

RESUMEN

Adolescent alcohol use is a strong predictor for the subsequent development of alcohol use disorders later in life. Additionally, adolescence is a critical period for the onset of affective disorders, which can contribute to problematic drinking behaviours and relapse, particularly in females. Previous studies from our laboratory have shown that exposure to adolescent intermittent ethanol (AIE) vapour alters glutamatergic transmission in the bed nucleus of the stria terminalis (BNST) and, when combined with adult stress, elicits sex-specific changes in glutamatergic plasticity and negative affect-like behaviours in mice. Building on these findings, the current work investigated whether BNST stimulation could substitute for stress exposure to increase the latency to consume a palatable food in a novel context (hyponeophagia) and promote social avoidance in adult mice with AIE history. Given the dense connections between the BNST and the parabrachial nucleus (PBN), a region involved in mediating threat assessment and feeding behaviours, we hypothesized that increased negative affect-like behaviours would be associated with PBN activation. Our results revealed that the chemogenetic stimulation of the dorsolateral BNST induced hyponeophagia in females with AIE history, but not in female controls or males of either group. Social interaction remained unaffected in both sexes. Notably, this behavioural phenotype was associated with higher activation of calcitonin gene-related peptide and dynorphin cells in the PBN. These findings provide new insights into the neurobiological mechanisms underlying the development of negative affect in females and highlight the potential involvement of the BNST-PBN circuitry in regulating emotional responses to alcohol-related stimuli.


Asunto(s)
Alcoholismo , Núcleos Parabraquiales , Núcleos Septales , Masculino , Ratones , Femenino , Animales , Etanol/farmacología
15.
Med. oral patol. oral cir. bucal (Internet) ; 29(1): e135-e144, Ene. 2024. tab, graf
Artículo en Inglés | IBECS | ID: ibc-229198

RESUMEN

Background: Graft-versus-host disease (GVHD) is an immune system reaction that occurs in patients with ahistory of hematopoietic stem cell transplantation (HSCT), in which the grafted donor's cells attack those of thehost. The objective of this systematic review was to present a study on oral squamous cell carcinoma (OSSC) thatdeveloped from GVHD areas in patients undergoing HSCT.Material and Methods: An electronic search was conducted in the databases PUBMED, WEB OF SCIENCE,SCOPUS, MEDLINE and SCIENCE DIRECT, according to PRISMA guidelines. Results: Of the 1582 results, 23 articles were included, resulting in 81 cases. The most common underlying diseasefor performing the transplant was Myeloid Leukemia (55.6%). The mean age was 39 years, with a predilection formales (64.2%). The tongue was the site of GVHD that most frequently underwent transformation to SCC (59.3%).The average time between transplantation and the development of GVHD was of approximately of 8 months, whilethe average period of development between transplantation and the development of OSCC was of approximately of111 months. The most common treatment to GVHD was cyclosporine associated with corticosteroids.Conclusions: OSCCs arising from areas of GVHD present a different evolution from conventional oral carcinomas,since they affect younger patients, smoking and alcohol are not important etiological factors and finally because theypresent good prognosis, but further studies with larger number cases followed are needed to confirm our findings.(AU)


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Trasplante Homólogo , Carcinoma de Células Escamosas de Cabeza y Cuello , Enfermedad Injerto contra Huésped , Salud Bucal , Medicina Oral , Patología Bucal , Higiene Bucal
16.
Alcohol Clin Exp Res (Hoboken) ; 48(1): 48-57, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38206283

RESUMEN

BACKGROUND: Adolescent alcohol use can produce long-lasting alterations in brain function, potentially leading to adverse health outcomes in adulthood. Emerging evidence suggests that chronic alcohol use can increase pain sensitivity or exacerbate existing pain conditions, but the potential neural mechanisms underlying these effects require further investigation. Here, we evaluate the impact of chronic ethanol vapor on mechanical sensitivity over the course of acute and protracted withdrawal in adolescent and adult male and female mice, and its potential association with alterations in corticotropin-releasing factor (CRF) signaling within the bed nucleus of the stria terminalis (BNST). METHODS: Adolescent and adult male and female mice underwent intermittent ethanol vapor exposure on 4 days/week for 2 weeks. Mechanical thresholds were evaluated 5 h and 7, 14, 21, and 28 d after cessation of ethanol exposure using the von Frey test. For mice with a history of adolescent ethanol exposure, brains were collected for in situ RNAscope processing after the final test. Messenger RNA expression of c-Fos, Crfr1, and Crf in the BNST subregions was examined. RESULTS: Exposure to intermittent ethanol vapor induced persistent mechanical hypersensitivity during withdrawal in both adolescent and adult mice. Notably, the effect was more transient in mice exposed to ethanol during adulthood, resolving by day 28 after ethanol exposure. Furthermore, both male and female mice with a history of adolescent ethanol exposure exhibited increased activation of CRF receptor type 1 (CRFR1) neurons within the dorsolateral BNST. CONCLUSIONS: Our results support the conclusion that intermittent ethanol exposure can induce mechanical hypersensitivity, potentially through the activation of BNST CRFR1 neurons. These findings provide a basis for future studies aimed at evaluating specific subpopulations of BNST neurons and their contribution to pain in individuals with a history of alcohol use.

17.
Sci Rep ; 14(1): 1119, 2024 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-38212602

RESUMEN

Previous studies of DNA sequence and karyotypic data have revealed high genetic diversity in the Physalaemus cuvieri - Physalaemus ephippifer species complex-a group of small leptodactylid frogs in South America. To date, seven major genetic lineages have been recognized in this group, with species delimitation tests supporting four to seven of them as valid species. Among these, only P. ephippifer shows heteromorphic sex chromosomes, but the implications of cytogenetic divergence for the evolution of this group are unknown. We analyzed karyotypic, mitochondrial DNA, and 3RAD genomic data to characterize a putative contact zone between P. ephippifer and P. cuvieri Lineage 1, finding evidence for admixture and karyotypic evolution. We also describe preliminary evidence for admixture between two other members of this species complex-Lineage 1 and Lineage 3 of P. cuvieri. Our study sheds new light on evolutionary relationships in the P. cuvieri - P. ephippifer species complex, suggesting an important role of karyotypic divergence in its evolutionary history and underscoring the importance of hybridization as a mechanism of sex chromosome evolution in amphibians.


Asunto(s)
Anuros , Cromosomas Sexuales , Animales , Cariotipificación , Anuros/genética , Cariotipo , Cromosomas Sexuales/genética , América del Sur , Filogenia , Evolución Molecular
18.
Pflugers Arch ; 476(3): 351-364, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38228895

RESUMEN

Despite the importance of physiological responses to stress in a short-term, chronically these adjustments may be harmful and lead to diseases, including cardiovascular diseases. The lateral hypothalamus (LH) has been reported to be involved in expression of physiological and behavioral responses to stress, but the local neurochemical mechanisms involved are not completely described. The corticotropin-releasing factor (CRF) neurotransmission is a prominent brain neurochemical system implicated in the physiological and behavioral changes induced by aversive threats. Furthermore, chronic exposure to aversive situations affects the CRF neurotransmission in brain regions involved in stress responses. Therefore, in this study, we evaluated the influence of CRF neurotransmission in the LH on changes in cardiovascular function and baroreflex activity induced by chronic variable stress (CVS). We identified that CVS enhanced baseline arterial pressure and impaired baroreflex function, which were followed by increased expression of CRF2, but not CRF1, receptor expression within the LH. Local microinjection of either CRF1 or CRF2 receptor antagonist within the LH inhibited the baroreflex impairment caused by CVS, but without affecting the mild hypertension. Taken together, the findings documented in this study suggest that LH CRF neurotransmission participates in the baroreflex impairment related to chronic stress exposure.


Asunto(s)
Hormona Liberadora de Corticotropina , Área Hipotalámica Lateral , Ratas , Animales , Hormona Liberadora de Corticotropina/metabolismo , Hormona Liberadora de Corticotropina/farmacología , Área Hipotalámica Lateral/metabolismo , Barorreflejo , Encéfalo/metabolismo , Transmisión Sináptica
19.
ACS Catal ; 14(1): 104-115, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38205021

RESUMEN

Interactions between catalysts and substrates can be highly complex and dynamic, often complicating the development of models to either predict or understand such processes. A dirhodium(II)-catalyzed C-H insertion of donor/donor carbenes into 2-alkoxybenzophenone substrates to form benzodihydrofurans was selected as a model system to explore nonlinear methods to achieve a mechanistic understanding. We found that the application of traditional methods of multivariate linear regression (MLR) correlating DFT-derived descriptors of catalysts and substrates leads to poorly performing models. This inspired the introduction of nonlinear descriptor relationships into modeling by applying the sure independence screening and sparsifying operator (SISSO) algorithm. Based on SISSO-generated descriptors, a high-performing MLR model was identified that predicts external validation points well. Mechanistic interpretation was aided by the deconstruction of feature relationships using chemical space maps, decision trees, and linear descriptors. Substrates were found to have a strong dependence on steric effects for determining their innate cyclization selectivity preferences. Catalyst reactive site features can then be matched to product features to tune or override the resultant diastereoselectivity within the substrate-dictated ranges. This case study presents a method for understanding complex interactions often encountered in catalysis by using nonlinear modeling methods and linear deconvolution by pattern recognition.

20.
Res Vet Sci ; 166: 105077, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37948882

RESUMEN

In this study we proposed to address the following question: "Are there differentially expressed sperm microRNAs related to fertility in bulls?". A systematic review of scientific literature until November 2022 was performed, in accordance with PRISMA guidelines. The main outcome was differentially expressed sperm microRNA from bulls with low versus high fertility profiles identified by using different methods such as field fertility evaluation and sperm laboratory analysis. Were identified 786 documents, of which 13 were selected for qualitative analysis. A total of 182 unique differentially expressed miRNAs were identified, among these, 49 miRNAs were found in common between at least two studies. It is believed that from these 49 miRNAs, it is possible that miRNAs such as miR-10a, -10b, -103, -15b, -122, -125b, -126-5p, -151-5p, -193a-5p, -196a, -27a-5p and -99b could be potential universal biomarkers to assess the reproductive potential of males.


Asunto(s)
MicroARNs , Masculino , Animales , Bovinos/genética , MicroARNs/genética , MicroARNs/metabolismo , Semen , Espermatozoides/metabolismo , Fertilidad/genética , Análisis de Semen/veterinaria
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