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1.
Int J Mol Sci ; 25(7)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38612507

RESUMO

Currently, there are no reliable prognostic factors to determine which upper tract urothelial carcinoma (UTUC) patients will progress after radical nephroureterectomy (RNU). We aim to evaluate whether liquid-biopsy-based biomarkers (circulating tumor cells (CTCs), cell-free DNA (cfDNA), and circulating tumor DNA (ctDNA)) were able to predict clinical outcomes in localized UTUC patients undergoing RNU. Twenty patients were prospectively enrolled between 2021 and 2023. Two blood samples were collected before RNU and three months later. CTCs and cfDNA were isolated and evaluated using the IsoFlux system and Quant-iT PicoGreen dsDNA kit, respectively. Droplet digital PCR was performed to determine ctDNA status. Cox regression analysis was performed on CTCs, cfDNA, and ctDNA at two different follow-up time points to examine their influence on tumor progression and cancer-specific survival (CSS). During a median follow-up of 18 months, seven (35%) patients progressed and three (15%) died. Multivariate analysis demonstrated that cfDNA levels three months after RNU are a significant predictor of tumor progression (HR = 1.085; p = 0.006) and CSS (HR = 1.168; p = 0.029). No associations were found between CTC enumeration and ctDNA status with any of the clinical outcomes evaluated. The evaluation of cfDNA levels in clinical practice could improve the disease management of UTUC patients.


Assuntos
Carcinoma de Células de Transição , Ácidos Nucleicos Livres , Neoplasias da Bexiga Urinária , Humanos , Carcinoma de Células de Transição/diagnóstico , Carcinoma de Células de Transição/genética , Prognóstico , Biomarcadores , Biópsia Líquida
2.
Artigo em Inglês | MEDLINE | ID: mdl-38217869

RESUMO

CONTEXT: Metabolic dysfunction-associated steatotic liver disease (MASLD) is characterized by the intracellular lipid accumulation in hepatocytes. Excess caloric intake and high-fat diets are considered to significantly contribute to MASLD development. OBJECTIVE: To evaluate the hepatic and serum fatty acid (FA) composition in patients with different stages of MASLD, and their relationship with FA dietary intake and MASLD-related risk factors. METHODS: This was a case-control study in patients with obesity undergoing bariatric surgery at a University Hospital between January 2020 and December 2021. Participants were distributed in three groups: no MASLD (n = 26), steatotic liver disease (n = 33), and metabolic dysfunction-associated steatohepatitis (n = 32). Hepatic and serum FAs levels were determined by GC-MS. The nutritional status was evaluated using validated food frequency questionnaires. The hepatic expression of genes involved in FA metabolism was analyzed by RT-qPCR. RESULTS: The hepatic, but not serum, FA profiles were significantly altered in patients with MASLD compared to those without MASLD. No differences were observed in FA intake between the groups. Levels of C16:0, C18:1, and the C18:1/C18:0 ratio were higher, while C18:0 levels and C18:0/C16:0 ratio were lower in patients with MASLD being significantly different between the three groups. Hepatic FA levels and ratios correlated with histopathological diagnosis and other MASLD-related parameters. The expression of genes involved in the FA metabolism was upregulated in patients with MASLD. CONCLUSION: Alterations in hepatic FA levels in MASLD patients were due to an enhancement of the de novo lipogenesis in the liver.

3.
Comput Struct Biotechnol J ; 23: 473-482, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38261868

RESUMO

TRP channels are important pharmacological targets in physiopathology. TRPV2 plays distinct roles in cardiac and neuromuscular function, immunity, and metabolism, and is associated with pathologies like muscular dystrophy and cancer. However, TRPV2 pharmacology is unspecific and scarce at best. Using in silico similarity-based chemoinformatics we obtained a set of 270 potential hits for TRPV2 categorized into families based on chemical nature and similarity. Docking the compounds on available rat TRPV2 structures allowed the clustering of drug families in specific ligand binding sites. Starting from a probenecid docking pose in the piperlongumine binding site and using a Gaussian accelerated molecular dynamics approach we have assigned a putative probenecid binding site. In parallel, we measured the EC50 of 7 probenecid derivatives on TRPV2 expressed in Pichia pastoris using a novel medium-throughput Ca2+ influx assay in yeast membranes together with an unbiased and unsupervised data analysis method. We found that 4-(piperidine-1-sulfonyl)-benzoic acid had a better EC50 than probenecid, which is one of the most specific TRPV2 agonists to date. Exploring the TRPV2-dependent anti-hypertensive potential in vivo, we found that 4-(piperidine-1-sulfonyl)-benzoic acid shows a sex-biased vasodilator effect producing larger vascular relaxations in female mice. Overall, this study expands the pharmacological toolbox for TRPV2, a widely expressed membrane protein and orphan drug target.

4.
Clin Chim Acta ; 552: 117678, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38042460

RESUMO

BACKGROUND: Fixed-dose combinations of antiretroviral drugs are commonly used to treat HIV infection and therapeutic monitoring is not part of routine clinical practice. However, drug concentrations monitoring might have role in different clinical scenarios as well as for research purposes. This study aimed to develop and validate UHPLC-MS/MS procedures for measuring total and unbound concentrations of bictegravir, dolutegravir, darunavir and doravirine in human plasma. MATERIAL AND METHODS: Equilibrium dialysis preceded sample preparation (based on protein precipitation) for measuring unbound antiretroviral concentrations. Chromatographic separations were achieved on an Acquity®-UPLC® HSS™-T3 column (50 mm × 2.1 mm; 1.8 µm) using a non-linear water/acetonitrile gradient containing 0.1 % formic acid at a 0.5 mL/min flow rate. Antiretrovirals were detected by tandem mass spectrometry in positive electrospray ionisation and multiple reaction monitoring modes. RESULTS: No significant interferences or carry-over were observed. Imprecisions, absolute relative biases, normalised matrix effects and recoveries were ≤15.0 %, ≤11.1 %, (94.7-104.1)% and (96.7-105.5)%, respectively. Non-linear measuring intervals were observed between (25-10,000) µg/L for total/plasma dialysate concentrations and linearity schemes (1.00-100) µg/L for buffer dialysate concentrations. CONCLUSIONS: The UHPLC-MS/MS procedures developed could be used for research purposes and therapeutic drug monitoring of antiretrovirals in routine clinical practice.


Assuntos
Infecções por HIV , Espectrometria de Massas em Tandem , Humanos , Espectrometria de Massas em Tandem/métodos , Darunavir , Cromatografia Líquida de Alta Pressão/métodos , Infecções por HIV/tratamento farmacológico , Diálise Renal , Soluções para Diálise
5.
Res Q Exerc Sport ; 95(1): 47-53, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36648412

RESUMO

In volleyball, the effect of different factors on serve performance has usually been analyzed with traditional statistical techniques such as logistic regression or discriminant analysis. Purpose: In this study, two of the main models used in unsupervised machine learning (cluster and principal component analysis) were applied to achieve these objectives: (a) to create groups of players considering their serve coefficient, age, height, and team ranking, and (b) to identify which variables related to the serve (type and performance), the players (role, age, and height), and the teams (ranking, match location, and quality of opposition) most explained the total variance of the data during an entire women's volleyball season. Method: A total of 20,936 serves were analyzed during the 132 matches played in the 2017-2018 season in the Liga Iberdrola (women Spanish first division). The variables were related to the serving action (type of serve and performance), the players' traits (player role, age, and height), and the teams' characteristics (final ranking, match location, quality of opposition, and tournament). Results: Cluster analysis showed five groups of players differing in age, serve coefficient, team ranking, and height. Principal component analysis showed how the first five components explained 72.12% of the total variance. From these components, serve coefficient, team ranking, match location, quality of opposition, and player role each contributed more than 10%. Conclusions: These findings can help coaches to improve talent selection and players' development according to competition demands.


Assuntos
Aprendizado de Máquina não Supervisionado , Voleibol , Humanos , Feminino , Análise por Conglomerados , Análise Discriminante , Estações do Ano
6.
J Hum Kinet ; 89: 171-185, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38053970

RESUMO

The aim of this study was to evaluate whether the rally length in high-level Spanish volleyball was longer in women than in men. A total of 1,786 rallies were observed: 792 for women and 994 for men. The recorded variables were match (quarter-final 1, quarter-final 2, semi-final 1, semi-final 2, final), gender (men, women), rally length (seconds), pseudo-rally (no, yes), and terminal event (ball out of sight, ball in/out, fault). Different non-parametric statistical techniques were used to compare the rally length between groups or subsets of data, i.e., the Kruskal-Wallis H test, the Mann-Whitney U test, quantile regression, and survival analysis. The mean and median rally length was significantly and slightly longer in women than in men. The rally length difference between genders was barely 1 s in quantile 0.5 or median, while in quantile 0.95, it was just over 4 s. In women, the probability of ending the rally at 3.9, 5.1, 10.2, and 43.9 s (at 4.4, 6.3, 11.6, and 43.9 s without pseudo-rallies) was 25%, 50%, 75%, and 100%, respectively. In men, the probability of ending the rally at 3.2, 4.3, 7.9, and 29.1 s (at 3.9, 4.8, 8.8, and 29.1 s without pseudo-rallies) was 25%, 50%, 75%, and 100%, respectively. These temporal thresholds can help volleyball coaches to train their players in a coherent manner.

7.
Eur Urol Oncol ; 2023 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-38072761

RESUMO

BACKGROUND: In ARCHES, treatment intensification of androgen deprivation therapy (ADT) with enzalutamide versus placebo improved clinical outcomes in metastatic hormone-sensitive prostate cancer (mHSPC). Understanding the benefits and tolerability of enzalutamide for men aged ≥75 yr may inform disease management. OBJECTIVE: To determine whether age is associated with clinical outcomes in mHSPC. DESIGN, SETTING, AND PARTICIPANTS: A post hoc analysis of the multinational, double-blind, randomized, placebo-controlled, phase 3 ARCHES trial in 1150 men with mHSPC (median follow-up [mo]: <75 yr, 44.6; ≥75 yr, 44.3) was performed. INTERVENTION: Randomization 1:1 to enzalutamide (160 mg/d) plus ADT or placebo plus ADT; stratification by disease volume and prior docetaxel use. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Overall survival (OS), radiographic progression-free survival (rPFS), safety, and other secondary endpoints were compared between age groups (<75 and ≥75 yr) and treatment arms (Cox proportional hazard models). RESULTS AND LIMITATIONS: Men aged <75 versus ≥75 yr had longer OS (enzalutamide plus ADT: hazard ratio [HR] 0.66; 95% confidence interval [CI] 0.47-0.91; p = 0.02; placebo plus ADT: HR 0.81; 95% CI 0.60-1.09; p = 0.13) and rPFS (enzalutamide plus ADT: HR 0.78; 95% CI 0.58-1.04; p = 0.12; placebo plus ADT: HR 0.98; 95% CI 0.74-1.30; p = 0.007). Enzalutamide improved OS (<75 yr: HR 0.61; 95% CI 0.47-0.79; ≥75 yr: HR 0.76; 95% CI 0.54-1.09) and secondary efficacy endpoints without evidence of statistical heterogeneity, and was generally well tolerated in both age groups, with minimal quality-of-life impact. Older versus younger patients experienced more frequent dose interruptions (20.2% vs 10.9%) and treatment-emergent adverse events (95.2% vs 89.1%). Post hoc examination and small sample size preclude definitive conclusions. CONCLUSIONS: Enzalutamide plus ADT improved efficacy outcomes and was generally well tolerated despite shorter treatment exposure in older patients, indicating enzalutamide's utility in patients with mHSPC aged <75 and ≥75 yr. PATIENT SUMMARY: Enzalutamide is a drug approved to treat men with prostate cancer. In this report, we compared patients aged <75 and ≥75 yr treated with enzalutamide plus androgen deprivation therapy to determine whether age affected how long they lived without the cancer spreading to other parts of their body. We found that, although younger patients had more favorable survival outcomes, enzalutamide was associated with longer survival and reduced disease spread in both age groups.

8.
Int J Mol Sci ; 24(23)2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-38068899

RESUMO

Circulating tumor DNA (ctDNA) has recently emerged as a real-time prognostic and predictive biomarker for monitoring cancer patients. Here, we aimed to ascertain whether tumor-agnostic ctDNA testing would be a feasible strategy to monitor disease progression and therapeutic response in muscle-invasive bladder cancer (MIBC) patients after radical cystectomy (RC). Forty-two MIBC patients who underwent RC were prospectively included. Blood samples from these patients were collected at different follow-up time points. Two specific mutations (TERT c.1-124C>T and ATM c.1236-2A>T) were analyzed in the patients' plasma samples by droplet digital PCR to determine their ctDNA status. During a median follow-up of 21 months, 24% of patients progressed in a median of six months. ctDNA status was identified as a prognostic biomarker of tumor progression before RC and 4 and 12 months later (HR 6.774, HR 3.673, and HR 30.865, respectively; p < 0.05). Lastly, dynamic changes in ctDNA status between baseline and four months later were significantly associated with patient outcomes (p = 0.045). In conclusion, longitudinal ctDNA analysis using a tumor-agnostic approach is a potential tool for monitoring MIBC patients after RC. The implementation of this testing in a clinical setting could improve disease management and patients' outcomes.


Assuntos
Ácidos Nucleicos Livres , DNA Tumoral Circulante , Neoplasias da Bexiga Urinária , Humanos , DNA Tumoral Circulante/genética , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia , DNA de Neoplasias , Biomarcadores , Músculos/patologia , Biomarcadores Tumorais/genética , Mutação
9.
Front Oncol ; 13: 1270962, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38098507

RESUMO

Background and aims: The spatial and temporal genetic heterogeneity of bladder cancer (BC) makes challenging to find specific drivers of metastatic disease, thus preventing to determine those BC patients at high risk of tumor progression. Our aim was to identify DNA mutations providing aggressive behavior to bladder tumors and analyze them in patients' cell-free DNA (cfDNA) during their follow-up after radical cystectomy (RC) in order to monitor tumor evolution. Methods: Six BC patients who underwent RC and presented disease progression during their follow-up were included. Next-generation sequencing was used to determine somatic mutations in several primary tumor and metastatic specimens from each patient. Shared DNA mutations between primary bladder tumor and metastatic sites were identified in cfDNA samples through droplet digital PCR. Results: Besides BC genetic heterogeneity, specific mutations in at least one of these genes -TERT, ATM, RB1, and FGFR3- were found in primary tumors and their metastases in all patients. These mutations were also identified in the patients' cfDNA at different follow-up time points. Additionally, the dynamic changes of these mutations in cfDNA allowed us to determine tumor evolution in response to treatment. Conclusion: The analysis of BC mutations associated with poor prognosis in plasma cfDNA could be a valuable tool to monitor tumor evolution, thus improving the clinical management of BC patients.

10.
Int. j. morphol ; 41(6): 1648-1652, dic. 2023. tab
Artigo em Espanhol | LILACS | ID: biblio-1528790

RESUMO

El proceso madurativo tiene una gran influencia sobre los factores antropométricos y las capacidades físicas del atleta, y por tanto, sobre el proceso de selección de talentos deportivos. El objetivo de este trabajo fue analizar el estado madurativo y las características antropométricas junto con la comparación de estos datos por sexo en una muestra de 39 jugadores jóvenes de voleibol dentro de un proceso de selección de talentos (19 damas de 14,88±1,05 años y 13 varones de 15,1 años). Se obtuvieron datos de edad cronológica, altura, peso, altura sentado, altura de la madre y padre, la edad pico de crecimiento, el "timing" o periodo de tiempo por encima o por debajo de la edad pico, altura al final del proceso madurativo, el porcentaje actual de altura máxima, los centímetros restantes y el estado madurativo (pre-púber, púber o pos-púber). Los jugadores mostraron una mayor altura en el momento de las mediciones (179,92±6,87 vs 171,05±4,80; p<0,001), así como una mayor altura final calculada (189,46±3,73 vs 178,52±5,17; p<0,001), en comparación a las jugadoras. El pico en la velocidad de crecimiento también fue superior en los jugadores (14,56±0,44 vs 12,60±0,57; p<0,001), aunque su timing era inferior al de las jugadoras (0,531±1,19 vs 2,27±0,64; p<0,001). Esto se debió a un mayor porcentaje de jugadores masculinos en estados puberales, incluyendo un jugador en estadio pre-puberal, mientras que fue abundante la presencia de jugadoras en estado pospuberal. Estos datos reflejan la gran cantidad de jugadores que tienden a estar en periodos avanzados de maduración en procesos de selección de talentos. Por tanto, entrenadores y seleccionadores deben contemplar estas variables para evitar sesgos en el proceso de identificación del talento deportivo.


SUMMARY: The maturation process has a great influence on the anthropometric factors and physical capabilities of the athlete, and therefore, on the selection process of sporting talents. The objective of this work was to analyze the maturational state and anthropometric characteristics together with the comparison of these data by sex in a sample of 39 young volleyball players within a talent selection process (19 ladies of 14.88±1. 05 years old and 13 males aged 15.1 years). Data were obtained on chronological age, height, weight, sitting height, height of the mother and father, peak age of growth, timing or period of time above or below the peak age, height at the end of the process. maturation, the current percentage of maximum height, the remaining centimeters and the maturation status (pre-pubertal, pubertal or post-pubertal). The players showed a greater height at the time of the measurements (179.92±6.87 vs. 171.05±4.80; p<0.001), as well as a greater final calculated height (189.46±3.73 vs. 178.52±5.17; p<0.001), compared to the female players. The peak in growth speed was also higher in male players (14.56±0.44 vs 12.60±0.57; p<0.001), although their timing was lower than that of female players (0.531±1.19 vs 2.27±0.64; p<0.001). This was due to a higher percentage of male players in pubertal states, including one player in a pre-pubertal stage, while the presence of female players in a post-pubertal stage was abundant. These data reflect the large number of players who tend to be in advanced periods of maturation in talent selection processes. Therefore, coaches and selectors must consider these variables to avoid biases in the process of identifying sporting talent.


Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Antropometria , Aptidão Física , Voleibol , Fatores Sexuais , Estudos Transversais
11.
Nat Commun ; 14(1): 7808, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38016939

RESUMO

Bacterial competition is a significant driver of toxin polymorphism, which allows continual compensatory evolution between toxins and the resistance developed to overcome their activity. Bacterial Rearrangement hot spot (Rhs) proteins represent a widespread example of toxin polymorphism. Here, we present the 2.45 Å cryo-electron microscopy structure of Tse5, an Rhs protein central to Pseudomonas aeruginosa type VI secretion system-mediated bacterial competition. This structural insight, coupled with an extensive array of biophysical and genetic investigations, unravels the multifaceted functional mechanisms of Tse5. The data suggest that interfacial Tse5-membrane binding delivers its encapsulated pore-forming toxin fragment to the target bacterial membrane, where it assembles pores that cause cell depolarisation and, ultimately, bacterial death.


Assuntos
Toxinas Bacterianas , Dermatite , Humanos , Microscopia Crioeletrônica , Toxinas Bacterianas/genética , Membranas , Proteínas de Bactérias/genética , Sequência de Bases , Membrana Celular
12.
Sports Health ; : 19417381231208706, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37950435

RESUMO

BACKGROUND: Physical testing is crucial for athlete monitoring, talent identification, optimizing training, and tailoring programs to enhance game-performance in elite competitions. HYPOTHESIS: Load-velocity (L-V) relationship variables discriminate between elite and junior volleyball players, correlate with volleyball-specific performance, and are generalizable across lower- and upper-body exercises. STUDY DESIGN: Cross-sectional study. LEVEL OF EVIDENCE: Level 3. METHODS: A total of 9 elite and 11 junior volleyball players were assessed for the L-V relationship (load-axis intercept [L0], velocity-axis intercept [v0], and area under the L-V relationship line [Aline]) during the countermovement jump (CMJ) and bench press throw (BPT) exercises. Block and spike jump height, as well as standing and jumping spike speed were assessed 24 hours later. RESULTS: Elite players presented greater magnitude in the L-V variables (P ≤ 0.03; effect size [ES] ≥ 1.06) and higher volleyball-specific performance (P ≤ 0.03; ES ≥ 1.09) than juniors (except for CMJ v0 and Aline). The L-V relationship variables were significantly associated with the block and spike jump height and jumping spike speed only in elite players (r ≥ 0.703 and P ≤ 0.04 in 11 out of 18 correlations). No significant associations were observed between CMJ and BPT for any L-V relationship variable (r ≤ 581; P ≥ 0.08, except for Aline in junior players). CONCLUSION: The L-V relationship is a practical procedure to assess volleyball players' maximal mechanical capacities, which are associated with volleyball-specific performance in elite players. However, these data should not be used interchangeably between playing standards or exercises. CLINICAL RELEVANCE: This information might help strength and conditioning coaches to prescribe more effective training programs that focus on developing the specific physical capacities necessary for players to potentially advance to elite status.

13.
J Antimicrob Chemother ; 78(11): 2696-2701, 2023 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-37725999

RESUMO

OBJECTIVES: To evaluate the efficacy and safety of the two-pill regimen bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF) plus darunavir/cobicistat as a switching strategy in heavily treatment-experienced people living with HIV (PLWH). METHODS: Multicentre, prospective, single-arm pilot clinical trial. Participants were virologically suppressed adults receiving a stable antiretroviral regimen of at least three pills from at least three drug families due to previous virological failures and/or toxicities with no documented resistance to integrase strand transfer inhibitors or darunavir (≥15 points, Stanford). Clinical and laboratory assessments were performed at 0, 4, 12, 24, 36 and 48 weeks. HIV-1 proviral DNA was amplified and sequenced by Illumina at baseline. Plasma bictegravir concentrations were determined in 22 patients using UHPLC-MS/MS. The primary study endpoint was viral load (VL)< 50 copies/mL at Week 48 (ITT). RESULTS: We enrolled 63 participants (92% men) with median baseline CD4 count of 515 cells/mm3 (IQR: 334.5-734.5), 24 years on ART (IQR: 15.9-27.8). The median number of pills was 4 (range: 3-10). At baseline, proviral DNA was amplified in 39 participants: 33/39 had resistance mutations. Three participants discontinued owing to toxicity. At 48 weeks, 95% had VL < 50 copies/mL by ITT and 100% by PP analysis. A modest increase was observed in the bictegravir plasma concentration, and a significant decrease in estimated glomerular filtration rate was observed only at Week 4, probably related to interaction with renal transporters. CONCLUSIONS: Our data suggest that BIC/FTC/TAF + darunavir/cobicistat is an effective, well-tolerated regimen that may improve convenience and, potentially, long-term success in stable heavily pre-treated PLWH.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Adulto , Feminino , Humanos , Masculino , Adenina/uso terapêutico , Alanina/uso terapêutico , Fármacos Anti-HIV/efeitos adversos , Antirretrovirais/uso terapêutico , Cobicistat/uso terapêutico , Darunavir/uso terapêutico , DNA/uso terapêutico , Emtricitabina/uso terapêutico , Infecções por HIV/tratamento farmacológico , Estudos Prospectivos , Espectrometria de Massas em Tandem
14.
Bioelectrochemistry ; 154: 108527, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37531663

RESUMO

Dynorphin A (DynA) is an endogenous neuropeptide that besides acting as a ligand of the κ-opioid receptor, presents some non-opioid pathophysiological properties associated to its ability to induce cell permeability similarly to cell-penetrating peptides (CPPs). Here, we use electrophysiology experiments to show that amphiphilic DynA generates aqueous pores in neutral membranes similar to those reported previously in charged membranes, but we also find other events thermodynamically incompatible with voltage-driven ion channel activity (i.e. non-zero currents with no applied voltage in symmetric salt conditions, reversal potentials that exceed the theoretical limit for a given salt concentration gradient). By comparison with current traces generated by other amphiphilic molecule known to spontaneously cross membranes, we hypothesize that DynA could directly translocate across neutral bilayers, a feature never observed in charged membranes following the same electrophysiological protocol. Our findings suggest that DynA interaction with the cellular membrane is modulated by the lipid charge distribution, enabling either passive ionic transport via membrane remodeling and pore formation or by peptide direct internalization independent of cellular transduction pathways.


Assuntos
Dinorfinas , Bicamadas Lipídicas , Bicamadas Lipídicas/química , Dinorfinas/farmacologia , Dinorfinas/análise , Dinorfinas/química , Membrana Celular/metabolismo , Peptídeos/química , Canais Iônicos/metabolismo
15.
Int J Mol Sci ; 24(15)2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37569828

RESUMO

The envelope (E) protein is a small polypeptide that can form ion channels in coronaviruses. In SARS coronavirus 2 (SARS-CoV-2), the agent that caused the recent COVID-19 pandemic, and its predecessor SARS-CoV-1, E protein is found in the endoplasmic reticulum-Golgi intermediate compartment (ERGIC), where virion budding takes place. Several reports claim that E protein promotes the formation of "cation-selective channels". However, whether this term represents specificity to certain ions (e.g., potassium or calcium) or the partial or total exclusion of anions is debatable. Herein, we discuss this claim based on the available data for SARS-CoV-1 and -2 E and on new experiments performed using the untagged full-length E protein from SARS-CoV-2 in planar lipid membranes of different types, including those that closely mimic the ERGIC membrane composition. We provide evidence that the selectivity of the E-induced channels is very mild and depends strongly on lipid environment. Thus, despite past and recent claims, we found no indication that the E protein forms cation-selective channels that prevent anion transport, and even less that E protein forms bona fide specific calcium channels. In fact, the E channel maintains its multi-ionic non-specific neutral character even in concentrated solutions of Ca2+ ions. Also, in contrast to previous studies, we found no evidence that SARS-CoV-2 E channel activation requires a particular voltage, high calcium concentrations or low pH, in agreement with available data from SARS-CoV-1 E. In addition, sedimentation velocity experiments suggest that the E channel population is mostly pentameric, but very dynamic and probably heterogeneous, consistent with the broad distribution of conductance values typically found in electrophysiological experiments. The latter has been explained by the presence of proteolipidic channel structures.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/metabolismo , Proteínas do Envelope Viral/química , Cálcio , Pandemias , Íons , Lipídeos
16.
World J Urol ; 41(10): 2847-2853, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37477683

RESUMO

BACKGROUND: The aim of this study was to determine the differences in the incidence, epidemiology, clinical characteristics and risk factors of infections in living donor kidney transplant recipients using robotic-assisted kidney transplantation (RAKT) and open approach. METHODS: We conducted a retrospective observational study from January 2016 to December 2019. For the risk factor analysis, a matched case-control study (1:1 ratio) was performed (robotic vs open). Control subjects were matched for living donor and time of transplantation. The data included de novo immunosuppressive regimen, delayed graft function, urological complications, acute allograft rejection and incidence, clinical features, microbiological findings and outcomes of infections. RESULTS: Ninety-four RAKT and 84 controls were included. There were no differences between groups in terms of age, gender, BMI, median days of hospitalization, immunosuppressive regimen, need for surgical urologic procedures post-transplantation, presence of urinary leak or acute allograft rejection. Thirty-five percent of all recipients analyzed presented an infection, mostly asymptomatic bacteriuria (49%), symptomatic urinary tract infection (31%) and surgical site infection (10%). Pseudomonas aeruginosa was the most frequent isolated microorganism in 67%, followed by E. coli (20%), Enterococcus faecalis (17%) and Klebsiella pneumoniae (10%). Eight percent of the microorganisms were multidrug resistant. The open kidney transplantation group presented more infections compared to RAKT (43 vs 27%, p = 0.04). After multivariate analysis, need for surgical urologic procedure post-transplantation (OR 6.2, 95% CI 1.1-35), BMI ≥ 30 (OR 3.6, 95% CI 1.5-9) and acute allograft rejection (OR 3.2, 95% CI 1.2-8.5) were associated with infection, whereas RAKT (OR 0.5, 95% CI 0.2-0.9) and the use of JJ catheter (OR 0.36, 95% CI 0.17-0.72) were protective factors. CONCLUSIONS: Infection is a frequent event in patients receiving a living donor kidney transplant. Acute allograft rejection, need for surgical urologic procedure post-transplantation and BMI were associated with infection, whereas robotic surgery was a protective factor in living donor kidney transplantation.


Assuntos
Transplante de Rim , Procedimentos Cirúrgicos Robóticos , Humanos , Transplante de Rim/métodos , Estudos de Casos e Controles , Procedimentos Cirúrgicos Robóticos/métodos , Escherichia coli , Rim
17.
Nutrients ; 15(13)2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37447318

RESUMO

The oxidized form of nicotinamide adenine dinucleotide (NAD+) is a critical metabolite for living cells. NAD+ may act either as a cofactor for many cellular reactions as well as a coenzyme for different NAD+-consuming enzymes involved in the physiological homeostasis of different organs and systems. In mammals, NAD+ is synthesized from either tryptophan or other vitamin B3 intermediates that act as NAD+ precursors. Recent research suggests that NAD+ precursors play a crucial role in maintaining the integrity of the gut barrier. Indeed, its deficiency has been associated with enhanced gut inflammation and leakage, and dysbiosis. Conversely, NAD+-increasing therapies may confer protection against intestinal inflammation in experimental conditions and human patients, with accumulating evidence indicating that such favorable effects could be, at least in part, mediated by concomitant changes in the composition of intestinal microbiota. However, the mechanisms by which NAD+-based treatments affect the microbiota are still poorly understood. In this context, we have focused specifically on the impact of NAD+ deficiency on intestinal inflammation and dysbiosis in animal and human models. We have further explored the relationship between NAD+ and improved host intestinal metabolism and immunity and the composition of microbiota in vivo. Overall, this comprehensive review aims to provide a new perspective on the effect of NAD+-increasing strategies on host intestinal physiology.


Assuntos
Microbioma Gastrointestinal , Animais , Humanos , NAD/metabolismo , Disbiose , Niacinamida/metabolismo , Inflamação , Mamíferos/metabolismo
18.
Urolithiasis ; 51(1): 91, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37358636

RESUMO

This study presents the surgical experience and long-term outcomes of living donor kidney transplantations involving asymptomatic kidney stones, using ex vivo flexible ureterorenoscopy (f-URS) during bench surgery for stone removal. Out of 1743 living kidney donors assessed between January 2012 and October 2022, 18 (1%) were diagnosed with urolithiasis. Among them, 12 donors were rejected, and 6 were accepted for kidney donation. Stone removal was successfully performed using f-URS during bench surgery, with no immediate complications or acute rejections observed. The study analyzed six living kidney transplants, of which 4 (67%) donors and three recipients were female, and 4 (67%) donors were blood-related to the recipient. The median age for donors and recipients was 57.5 and 51.5 years, respectively. The stones, primarily located in the lower calyx, had a median size of 6 mm. The median cold ischemia time during surgery was 41.6 min, and ex vivo f-URS ensured complete stone removal in all cases. After a median follow-up of 120 months, the remaining grafts were functioning well, and no urinary stone recurrence was observed in either the recipients or living donors. The findings suggest that bench f-URS is a safe approach for managing urinary stones in kidney grafts, providing good functional outcomes without stone recurrence in selected cases.


Assuntos
Cálculos Renais , Litíase , Cálculos Urinários , Urolitíase , Humanos , Feminino , Masculino , Doadores Vivos , Seguimentos , Rim/cirurgia , Cálculos Renais/cirurgia , Urolitíase/cirurgia , Ureteroscopia , Aloenxertos/cirurgia , Estudos Retrospectivos , Resultado do Tratamento
19.
J Virol ; 97(6): e0035023, 2023 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-37212688

RESUMO

African swine fever virus (ASFV) is causing a devastating pandemic in domestic and wild swine in Central Europe to East Asia, resulting in economic losses for the swine industry. The virus contains a large double-stranded DNA genome that contains more than 150 genes, most with no experimentally characterized function. In this study, we evaluate the potential function of the product of ASFV gene B117L, a 115-amino-acid integral membrane protein transcribed at late times during the virus replication cycle and showing no homology to any previously published protein. Hydrophobicity distribution along B117L confirmed the presence of a single transmembrane helix, which, in combination with flanking amphipathic sequences, composes a potential membrane-associated C-terminal domain of ca. 50 amino acids. Ectopic transient cell expression of the B117L gene as a green fluorescent protein (GFP) fusion protein revealed the colocalization with markers of the endoplasmic reticulum (ER). Intracellular localization of various B117L constructs also displayed a pattern for the formation of organized smooth ER (OSER) structures compatible with the presence of a single transmembrane helix with a cytoplasmic carboxy terminus. Using partially overlapping peptides, we further demonstrated that the B117L transmembrane helix has the capacity to establish spores and ion channels in membranes at low pH. Furthermore, our evolutionary analysis showed the high conservation of the transmembrane domain during the evolution of the B117L gene, indicating that the integrity of this domain is preserved by the action of the purifying selection. Collectively our data support a viroporin-like assistant role for the B117L gene-encoded product in ASFV entry. IMPORTANCE ASFV is responsible for an extensively distributed pandemic causing important economic losses in the pork industry in Eurasia. The development of countermeasures is partially limited by the insufficient knowledge regarding the function of the majority of the more than 150 genes present on the virus genome. Here, we provide data regarding the functional experimental evaluation of a previously uncharacterized ASFV gene, B117L. Our data suggest that the B117L gene encodes a small membrane protein that assists in the permeabilization of the ER-derived envelope during ASFV infection.


Assuntos
Vírus da Febre Suína Africana , Permeabilidade da Membrana Celular , Proteínas de Membrana , Proteínas Virais , Internalização do Vírus , Animais , Febre Suína Africana/virologia , Vírus da Febre Suína Africana/genética , Vírus da Febre Suína Africana/metabolismo , Genoma Viral , Concentração de Íons de Hidrogênio , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Suínos , Proteínas Virais/genética , Proteínas Virais/metabolismo , Permeabilidade da Membrana Celular/genética
20.
Eur Urol ; 84(2): 229-241, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37179240

RESUMO

BACKGROUND: Few phase 3 studies have evaluated optimal systemic treatment strategies for patients with oligometastatic hormone-sensitive prostate cancer (HSPC), who may be at risk of undertreatment. OBJECTIVE: To evaluate outcomes for patients with oligometastatic and polymetastatic HSPC treated with enzalutamide plus androgen deprivation therapy (ADT) versus placebo plus ADT. DESIGN, SETTING, AND PARTICIPANTS: This was a post hoc analysis of data for 927 patients with nonvisceral metastatic HSPC in the ARCHES trial (NCT02677896). INTERVENTION: Patients were randomized 1:1 to enzalutamide (160 mg/d orally) plus ADT or placebo plus ADT with HSPC categorized as oligometastatic (1-5 metastases) or polymetastatic (≥6 metastases). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The treatment effect on radiographic progression-free survival (rPFS), overall survival (OS), and secondary efficacy endpoints was evaluated in terms of the number of metastases. Safety was assessed. Cox proportional hazards models were used to generate hazard ratios (HRs). The Brookmeyer and Crowley method was used to generate 95% confidence intervals (CIs) for Kaplan-Meier median values. RESULTS AND LIMITATIONS: Enzalutamide plus ADT improved rPFS (HR 0.27, 95% CI 0.16-0.46; p < 0.001), OS (HR 0.59, 95% CI 0.40-0.87; p < 0.005), and secondary endpoints in patients with oligometastatic or polymetastatic disease (rPFS: HR 0.33, 95% CI 0.23-0.46; p < 0.001; OS: HR 0.55, 95% CI 0.41-0.74; p < 0.001). Safety profiles were generally similar across subgroups. Limitations include the small numbers of patients with fewer than three metastases. CONCLUSIONS: This post hoc analysis demonstrated the utility of enzalutamide, irrespective of metastatic burden or type of oligometastatic disease, and suggests that earlier treatment intensification with systemic potent androgen receptor inhibition is advantageous. PATIENT SUMMARY: This study considered two treatment options for metastatic hormone-sensitive prostate cancer in patients with one to five metastases or six or more metastases. Treatment with enzalutamide plus ADT improved survival and other outcomes over ADT alone, whether patients had few or many metastases.


Assuntos
Neoplasias de Próstata Resistentes à Castração , Neoplasias da Próstata , Masculino , Humanos , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Antagonistas de Androgênios/uso terapêutico , Androgênios/uso terapêutico , Intervalo Livre de Doença , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Resultado do Tratamento
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