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1.
J Cell Biol ; 223(10)2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-38949648

RESUMO

The diverse roles of the dynein motor in shaping microtubule networks and cargo transport complicate in vivo analysis of its functions significantly. To address this issue, we have generated a series of missense mutations in Drosophila Dynein heavy chain. We show that mutations associated with human neurological disease cause a range of defects, including impaired cargo trafficking in neurons. We also describe a novel microtubule-binding domain mutation that specifically blocks the metaphase-anaphase transition during mitosis in the embryo. This effect is independent from dynein's canonical role in silencing the spindle assembly checkpoint. Optical trapping of purified dynein complexes reveals that this mutation only compromises motor performance under load, a finding rationalized by the results of all-atom molecular dynamics simulations. We propose that dynein has a novel function in anaphase progression that depends on it operating in a specific load regime. More broadly, our work illustrates how in vivo functions of motors can be dissected by manipulating their mechanical properties.


Assuntos
Anáfase , Proteínas de Drosophila , Drosophila melanogaster , Dineínas , Microtúbulos , Animais , Dineínas/metabolismo , Dineínas/genética , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/genética , Microtúbulos/metabolismo , Microtúbulos/genética , Simulação de Dinâmica Molecular , Mutação/genética , Fuso Acromático/metabolismo , Fuso Acromático/genética , Humanos , Mutação de Sentido Incorreto
2.
Front Psychol ; 15: 1363544, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38962225

RESUMO

Purpose: Recreational and competitive slalom waterskiing is increasingly popular among individuals with spinal cord injuries (SCI), particularly for those with paraplegia using sit-skis. A key component of slalom skiing is the deep-water start (DWS), yet little is known about the physiological and physical demands of this activity when the athlete is seated. This study aims to fill this gap by focusing on the training requirements for a seated slalom athlete. Materials and methods: Focusing on a young male athlete with paraplegia, this case study evaluates the effectiveness and efficiency of traditional (TDWS) and alternative (ADWS) DWS techniques during seated slalom waterskiing sessions. It assesses internal training load (TL) through heart rate (HR) zones and session rating of perceived exertion (sRPE), alongside pre- and post-session handgrip strength measurements to gauge peripheral muscle fatigue. Results and conclusions: Performing the ADWS, achieving a full success rate, proved more effective but slightly more time-consuming than TDWS, which had limited success. HR during DWS maneuvers ranged from 63.2 to 81.3% of maximal HR, with most sessions occurring below the ventilatory threshold, thus perceived as hard effort. A moderate yet non-significant correlation was found between HR and sRPE-based TL. A significant reduction in handgrip strength post-session underscores the activity's demands. These insights illuminate the technical, physiological, and physical challenges in mastering DWS for seated slalom athletes with SCI, providing valuable guidance for the development of tailored training programs and techniques in this sport.

3.
Int J Mol Sci ; 25(11)2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38892424

RESUMO

Parasitic diseases, predominantly prevalent in developing countries, are increasingly spreading to high-income nations due to shifting migration patterns. The World Health Organization (WHO) estimates approximately 300 million annual cases of giardiasis. The emergence of drug resistance and associated side effects necessitates urgent research to address this growing health concern. In this study, we evaluated over eleven thousand pharmacological compounds sourced from the FDA database to assess their impact on the TATA-binding protein (TBP) of the early diverging protist Giardia lamblia, which holds medical significance. We identified a selection of potential pharmacological compounds for combating this parasitic disease through in silico analysis, employing molecular modeling techniques such as homology modeling, molecular docking, and molecular dynamics simulations. Notably, our findings highlight compounds DB07352 and DB08399 as promising candidates for inhibiting the TBP of Giardia lamblia. Also, these compounds and DB15584 demonstrated high efficacy against trophozoites in vitro. In summary, this study identifies compounds with the potential to combat giardiasis, offering the prospect of specific therapies and providing a robust foundation for future research.


Assuntos
Antiprotozoários , Giardia lamblia , Giardíase , Simulação de Acoplamento Molecular , United States Food and Drug Administration , Giardíase/tratamento farmacológico , Giardia lamblia/efeitos dos fármacos , Antiprotozoários/farmacologia , Antiprotozoários/química , Estados Unidos , Humanos , Proteínas de Protozoários/química , Proteínas de Protozoários/metabolismo , Proteínas de Protozoários/antagonistas & inibidores , Simulação de Dinâmica Molecular
5.
Artigo em Inglês | MEDLINE | ID: mdl-38889326

RESUMO

ABSTRACT: This scoping review aimed to explore the characteristics and performance factors of competitive Para-cyclists. A systematic search for studies on competitive Para-cycling on WOS, PubMed, SPORTDiscus and Scopus was performed until December 2023. Five methodological phases were followed: (i) identifying the research question, (ii) identifying relevant studies, (iii) study selection, (iv) charting the data, and (v) collating, summarizing, and reporting the results. A systematic search across multiple databases was performed until March 2024. Five methodological phases were employed: identifying the research question, relevant studies, study selection, charting data, and summarizing results. A total of 36 relevant studies were selected. Three main research themes emerged: Sport performance (n = 15), Biomechanics (n = 12), and Physical and mental health (n = 9). Despite progress, gaps were identified, particularly in physiological response to exercise, fitness, and training. Biomechanics studies focused on prosthetic use and aerodynamics, mostly involving lower-limb amputees and simulated tandem competition. Injury risk in Para-cycling appeared comparable to able-bodied cycling, but comprehensive studies considering confounding variables are needed. Overall, while research on Para-cycling is growing, more studies with larger and diverse samples across all sport classes are essential to advance scientific understanding in this field.

6.
J Pharmacol Toxicol Methods ; 127: 107511, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38710237

RESUMO

The Health and Environmental Sciences Institute (HESI) is a nonprofit organization dedicated to resolving global health challenges through collaborative scientific efforts across academia, regulatory authorities and the private sector. Collaborative science across non-clinical disciplines offers an important keystone to accelerate the development of safer and more effective medicines. HESI works to address complex challenges by leveraging diverse subject-matter expertise across sectors offering access to resources, data and shared knowledge. In 2008, the HESI Cardiac Safety Committee (CSC) was established to improve public health by reducing unanticipated cardiovascular (CV)-related adverse effects from pharmaceuticals or chemicals. The committee continues to significantly impact the field of CV safety by bringing together experts from across sectors to address challenges of detecting and predicting adverse cardiac outcomes. Committee members have collaborated on the organization, management and publication of prospective studies, retrospective analyses, workshops, and symposia resulting in 38 peer reviewed manuscripts. Without this collaboration these manuscripts would not have been published. Through their work, the CSC is actively addressing challenges and opportunities in detecting potential cardiac failure modes using in vivo, in vitro and in silico models, with the aim of facilitating drug development and improving study design. By examining past successes and future prospects of the CSC, this manuscript sheds light on how the consortium's multifaceted approach not only addresses current challenges in detecting potential cardiac failure modes but also paves the way for enhanced drug development and study design methodologies. Further, exploring future opportunities and challenges will focus on improving the translational predictability of nonclinical evaluations and reducing reliance on animal research in CV safety assessments.


Assuntos
Cardiotoxicidade , Humanos , Animais , Cardiotoxicidade/prevenção & controle , Cardiotoxicidade/etiologia , Academias e Institutos , Desenvolvimento de Medicamentos/métodos , Doenças Cardiovasculares , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/prevenção & controle
7.
Int J Urol ; 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38757476

RESUMO

OBJECTIVE: The study evaluated the anatomical and functional outcomes, as well as the safety data of laparoscopic sacrocolpopexy (LSC) for pelvic organ prolapse (POP) using a lightweight macroporous mesh. METHODS: A multicentric observational study was developed including five expert centers between March 2011 and December 2019. Inclusion criteria were female patients with symptomatic ≥stage II POP (POP-Q classification), who underwent a LSC. A lightweight and macroporous mesh device (Surelift Uplift) was used. Baseline anatomical positions were evaluated using POP-Q stage. The anatomical outcomes and procedural complications were assessed during the postoperative period. Primary outcomes were anatomical success, defined as POP-Q stage ≤I, and subjective success, defined as no bothersome bulge symptoms, and no repeat surgery or pessary use for recurrent prolapse. RESULTS: A total of 325 LSCs were analyzed with a median patient age of 66 (interquartile range [IQR] 61-73). After a median follow-up of 68 months (IQR 46.5-89), anatomical success was found in 88.9%, whereas subjective success was seen in 98.5% of the patients. Recurrent prolapse presented as cystocele (1.5%). Reported complications were bladder (4.6%) or rectum lesions (0.6%), de novo urinary incontinence (12.9%), and mesh extrusion (1.2%). CONCLUSIONS: LSC provides significant clinical improvement and excellent anatomical results, with a low risk of serious complications for women with ≥2 grade POP in a real clinical practice setting.

9.
Euro Surveill ; 29(12)2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38516785

RESUMO

BackgroundIn countries with a low TB incidence (≤ 10 cases/100,000 population), active pulmonary tuberculosis (PTB) mostly affects vulnerable populations with limited access to healthcare. Thus, passive case-finding systems may not be successful in detecting and treating cases and preventing further transmission. Active and cost-effective search strategies can overcome this problem.AimWe aimed to review the evidence on the cost-effectiveness (C-E) of active PTB screening programmes among high-risk populations in low TB incidence countries.MethodsWe performed a systematic literature search covering 2008-2023 on PubMed, Embase, Center for Reviews and Dissemination, including Database of Abstracts of Reviews of Effects (DARE), National Health Services Economic Evaluation Database (NHS EED), Global Index Medicus and Cochrane Central Register of Controlled Trials (CENTRAL).ResultsWe retrieved 6,318 articles and included nine in this review. All included studies had an active case-finding approach and used chest X-ray, tuberculin skin test, interferon-gamma release assay and a symptoms questionnaire for screening. The results indicate that screening immigrants from countries with a TB incidence > 40 cases per 100,000 population and other vulnerable populations as individuals from isolated communities, people experiencing homelessness, those accessing drug treatment services and contacts, is cost-effective in low-incidence countries.ConclusionIn low-incidence countries, targeting high-risk groups is C-E. However, due to the data heterogenicity, we were unable to compare C-E. Harmonisation of the methods for C-E analysis is needed and would facilitate comparisons. To outline comprehensive screening and its subsequent C-E analysis, researchers should consider multiple factors influencing screening methods and outcomes.


Assuntos
Tuberculose Pulmonar , Tuberculose , Humanos , Análise Custo-Benefício , Incidência , Tuberculose/diagnóstico , Tuberculose/epidemiologia , Teste Tuberculínico , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/epidemiologia , Tuberculose Pulmonar/prevenção & controle , Programas de Rastreamento/métodos
10.
J Parasitol Res ; 2024: 4775361, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38495541

RESUMO

Ecoepidemiology is an emerging field that attempts to explain how biotic, environmental, and even social factors influence the dynamics of infectious diseases. Particularly in vector-borne diseases, the study under this approach offers us an overview of the pathogens, vectors, and hosts that coexist in a given region and their ecological determinants. As a result of this, risk predictions can be established in a changing environment and how it may impact human populations. This paper is aimed at evaluating some ecoepidemiological characteristics of Chagas disease in a natural reserve in southeastern Mexico that borders human settlements. We carry out a cross-sectional study in 2022 where we search insects manually and with light traps. We set traps for small mammals and bats and conducted interviews with the inhabitants living around the study site. We identified the presence of Triatoma dimidiata and T. huehuetenanguensis species with a percentage of TcI T. cruzi infection of 68.4% (95% CI: 66.9-69.9). Temperature and humidity were not determining factors for the probability of insect capture. Of the 108 wild mammals (Chiroptera, Rodentia, and Didelphimorphia), none was infected with T. cruzi. Knowledge about Chagas disease in nearby inhabitants is poor, and some characteristics were found on the periphery of dwellings that could offer a refuge for insect vectors. With this information, surveillance strategies can be generated in the study area that reduce the risk of transmission of T. cruzi parasite to humans, and it is expected to motivate the use of this field in future research.

11.
Rev Soc Bras Med Trop ; 57: e007032024, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38537000

RESUMO

BACKGROUND: Chagas disease, a zoonosis transmitted mainly by hematophagous insects of the subfamily Triatominae, is caused by Trypanosoma cruzi, classified into six discrete typing units (DTUs: TcI-TcVI and Tcbat). METHODS: Insect vectors were collected from 84 human dwellings in the municipality of Santo Domingo Tehuantepec, Oaxaca, Mexico; 4.76% were infested. DTUs were determined using conventional and nested PCR. RESULTS: The infection rate was 43.6%. All insects were infected with TcI while one specimen showed mixed infection with TcII. CONCLUSIONS: This is the first report of T. cruzi mixed infection in Triatoma phyllosoma, its main vector in the study region.


Assuntos
Doença de Chagas , Coinfecção , Triatoma , Trypanosoma cruzi , Animais , Humanos , Trypanosoma cruzi/genética , México , Genótipo
12.
Sports (Basel) ; 12(2)2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38393271

RESUMO

This study aimed to compare the effects of an 8-week short-term training program, comprising repeated sprints or running-based high-intensity intermittent training (HIIT), on the aerobic fitness and repeated sprint ability (RSA) performance of sub-elite basketball referees. Twenty male referees participated in supervised training sessions twice a week. They were randomly assigned to either the RSA-based group (RSAG) or the running-based HIIT group (HIITG). The RSAG conducted 3-4 sets of 8 × 20-m all-out sprints, while the HIITG performed 2-3 sets of 6 × 20-s runs at 90% of their maximal velocity achieved in the 30-15 intermittent fitness test (30-15IFT). Referees underwent a graded exercise test on a treadmill, the 30-15IFT, and an RSA test before and after the training program. Both groups showed significant improvement (~3%) in the fastest (22.6 ± 1.4 vs. 23.4 ± 1.7 and 22.0 ±1.9 vs. 22.4 ± 1.7 km·h-1 in RSAG and HIITG, respectively) and mean (21.5 ± 1.2 vs. 22.4 ± 1.4 and 21.3 ± 1.8 vs. 21.7 ± 1.6 km·h-1 in RSAG and HIITG, respectively) sprint velocity of the RSA test (p < 0.05). Moreover, positive changes (p < 0.05) were observed in the 30-15IFT maximal velocity (18.6 ± 1.1 vs. 19.3 ± 1.0 and 19.4 ± 0.9 vs. 20.5 ± 0.9 km·h-1 in RSAG and HIITG, respectively). In conclusion, an 8-week training intervention using either RSA or running-based HIIT led to similar improvements in referees' RSA performance and specific aerobic fitness measures. These findings could assist in devising tailored training programs for basketball referees.

13.
Anim Reprod Sci ; 262: 107426, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38377631

RESUMO

The reproductive management of the buffalo species still faces several unresolved problems, which directly affect the productivity of the herd, one of them being the presence of repeat breeder females. Given this scenario, this study aimed to verify the developmental competence of oocytes obtained from repeat breeder females and submitted to parthenogenetic activation. In addition, embryo gene expression was compared to normally fertile females. Murrah buffaloes were divided into two groups: repeat breeder (RB, n = 8) and normally fertile or control (CR, n = 7). Cumulus-oocyte complexes (COCs) were aspirated by transvaginal ovum pick-up from estrus synchronized females. The COCs were submitted to IVM for 24 h, and subsequently, the oocytes were activated using ionomycin, followed by 6-DMAP. Afterwards, the presumptive parthenotes were cultured for six or seven days in a microenvironment of 5 % CO2, 5 % O2, and 90 % N2 at 38.5 °C. The expression of OCT4, GLUT1, BCL2 and TFAM genes from blastocysts was evaluated. The overall COCs recovery rate was 70.9 % (190/268). The maturation (57.8 vs 71.1), cleavage (45.2 vs 62.2) and blastocyst (30.1 vs 45.9) rates did not differ (P > 0.05) between RB and CR females, respectively. Similarly, no significant difference (P > 0.05) was observed for the expression of studied genes in both RB and CR females. In conclusion, oocytes obtained from RB were as developmentally competent as those collected from CR females, with similar energy metabolism and in vitro development capacity. Thus, the low fertility rate of repeat breeder buffaloes, when compared to normal cyclic females, must be due to subsequent events to the blastocyst stage.


Assuntos
Búfalos , Clima Tropical , Feminino , Animais , Búfalos/genética , Fertilização in vitro/veterinária , Oócitos/fisiologia , Blastocisto/fisiologia , Expressão Gênica , Técnicas de Maturação in Vitro de Oócitos/veterinária , Desenvolvimento Embrionário/fisiologia
15.
Acta Trop ; 249: 107063, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37944838

RESUMO

The subfamily Triatominae includes a group of hematophagous insects, vectors of the parasite Trypanosoma cruzi, which is the etiological agent of Chagas disease, also known as American trypanosomiasis. Triatomines occur in the Old and New World and occupy diverse habitats including tropical and temperate areas. Some studies suggest the distributions of triatomines group into three or four regions. This study objectively determined bioregions focused specifically on New World Triatominae, using clustering and ordination analysis. We also identified indicator species by bioregion and investigated relationships among bioregions and environmental variables using redundancy analysis and multivariate regression trees. We delineated seven bioregions specific to Triatominae and linked each with indicator species. This result suggests more biogeographical structure exists than was revealed in earlier studies that were more general, subjective, and based on older taxonomic and distributional information. Precipitation, elevation, and vegetation were important variables in the delimitating bioregions. This implies that more detailed study of how these factors influence triatomine distributions could benefit understanding of how Chagas disease is spread.


Assuntos
Doença de Chagas , Triatominae , Trypanosoma cruzi , Animais , Triatominae/parasitologia , Insetos Vetores/parasitologia , Ecossistema
16.
Rev. Soc. Bras. Med. Trop ; 57: e00703, 2024. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1550683

RESUMO

ABSTRACT Background: Chagas disease, a zoonosis transmitted mainly by hematophagous insects of the subfamily Triatominae, is caused by Trypanosoma cruzi, classified into six discrete typing units (DTUs: TcI-TcVI and Tcbat). Methods: Insect vectors were collected from 84 human dwellings in the municipality of Santo Domingo Tehuantepec, Oaxaca, Mexico; 4.76% were infested. DTUs were determined using conventional and nested PCR. Results: The infection rate was 43.6%. All insects were infected with TcI while one specimen showed mixed infection with TcII. Conclusions: This is the first report of T. cruzi mixed infection in Triatoma phyllosoma, its main vector in the study region.

17.
Artigo em Inglês | MEDLINE | ID: mdl-38052044

RESUMO

Background: The Trypanosoma cruzi parasite is the causal agent of Chagas disease, recognized by the World Health Organization as a neglected tropical disease. Currently there are seven discrete typing units (DTUs) of T. cruzi distributed in America, but there are still gaps about its distribution in some endemic regions. Materials and Methods: Seventeen units isolated from Chiapas and Oaxaca in Mexico were identified by amplification of the C-5 sterol desaturase gene. Results: Three DTUs of T. cruzi, TcI (6), TcII (10), and TcIV (1) were detected by comparing polymorphic sites in specific regions. Conclusions: New DTUs are reported for both states, where TcII was the most common DTU. The genetic characterization of the isolates can help to understand the epidemiology of Chagas disease.

18.
Anim Reprod ; 20(3): e20230055, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38025995

RESUMO

In vitro embryo production (IVEP) is an extremely important tool for genetic improvement in livestock and it is the biotechnology that has grown the most recently. However, multiple ovulation followed by embryo transfer is still considered the leading biotechnology for embryo production in small ruminants. This review aimed to identify what is still missing for more efficient diffusion of IVEP in small ruminants, going through the IVEP steps and highlighting the main factors affecting the outcomes. Oocyte quality is essential for the success of IVEP and an aspect to be considered in small ruminants is their reproductive seasonality and strategies to mitigate the effect of season. The logistics for oocyte collection from live females is more complex than in cattle, and tools to simplify this collection system and/or to promote an alternative way of recovering oocytes may be an important point in this scenario. The heterogeneity of oocytes collected from growing follicles in live females or from ovaries collected from abattoirs remains a challenge, and there is a demand to standardize/homogenize the hormonal stimulatory protocols and IVM protocols for each source of oocytes. The use of sexed semen is technically possible, however the low market demand associated with the high costs of the sexing process prevents the routine use of this technique, but its higher availability is an important aspect aiming for greater dissemination of IVEP. New noninvasive approaches for embryo selection are key factors since the selection for transfer or cryopreservation is another difficulty faced among laboratories. Embryo selection is based on morphological traits, although these are not necessarily reliable in predicting pregnancy. Several issues described in this review must be considered by researchers in other to promote the diffusion of IVEP in small ruminants.

20.
Nature ; 623(7988): 842-852, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37853127

RESUMO

Optimum protein function and biochemical activity critically depends on water availability because solvent thermodynamics drive protein folding and macromolecular interactions1. Reciprocally, macromolecules restrict the movement of 'structured' water molecules within their hydration layers, reducing the available 'free' bulk solvent and therefore the total thermodynamic potential energy of water, or water potential. Here, within concentrated macromolecular solutions such as the cytosol, we found that modest changes in temperature greatly affect the water potential, and are counteracted by opposing changes in osmotic strength. This duality of temperature and osmotic strength enables simple manipulations of solvent thermodynamics to prevent cell death after extreme cold or heat shock. Physiologically, cells must sustain their activity against fluctuating temperature, pressure and osmotic strength, which impact water availability within seconds. Yet, established mechanisms of water homeostasis act over much slower timescales2,3; we therefore postulated the existence of a rapid compensatory response. We find that this function is performed by water potential-driven changes in macromolecular assembly, particularly biomolecular condensation of intrinsically disordered proteins. The formation and dissolution of biomolecular condensates liberates and captures free water, respectively, quickly counteracting thermal or osmotic perturbations of water potential, which is consequently robustly buffered in the cytoplasm. Our results indicate that biomolecular condensation constitutes an intrinsic biophysical feedback response that rapidly compensates for intracellular osmotic and thermal fluctuations. We suggest that preserving water availability within the concentrated cytosol is an overlooked evolutionary driver of protein (dis)order and function.


Assuntos
Substâncias Macromoleculares , Proteínas , Solventes , Termodinâmica , Água , Morte Celular , Citosol/química , Citosol/metabolismo , Homeostase , Substâncias Macromoleculares/química , Substâncias Macromoleculares/metabolismo , Concentração Osmolar , Pressão , Proteínas/química , Proteínas/metabolismo , Solventes/química , Solventes/metabolismo , Temperatura , Fatores de Tempo , Água/química , Água/metabolismo
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