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1.
Invest New Drugs ; 42(3): 318-325, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38758478

RESUMEN

Cancer is a disease caused by uncontrolled cell growth that is responsible for several deaths worldwide. Breast cancer is the most common type of cancer among women and is the leading cause of death. Chemotherapy is the most commonly used treatment for cancer; however, it often causes various side effects in patients. In this study, we evaluate the antineoplastic activity of a parent compound based on a combretastatin A4 analogue. We test the compound at 0.01 mg mL- 1, 0.1 mg mL- 1, 1.0 mg mL- 1, 10.0 mg mL- 1, 100.0 mg mL- 1, and 1,000.0 mg mL- 1. To assess molecular antineoplastic activity, we conduct in vitro tests to determine the viability of Ehrlich cells and the blood mononuclear fraction. We also analyze the cytotoxic behavior of the compound in the blood and blood smear. The results show that the molecule has a promising antineoplastic effect and crucial anticarcinogenic action. The toxicity of blood cells does not show statistically significant changes.


Asunto(s)
Estilbenos , Estilbenos/farmacología , Animales , Supervivencia Celular/efectos de los fármacos , Ratones , Leucocitos Mononucleares/efectos de los fármacos , Antineoplásicos/farmacología , Humanos , Carcinoma de Ehrlich/tratamiento farmacológico
2.
J Anim Ecol ; 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38847240

RESUMEN

Food webs depict the tangled web of trophic interactions associated with the functioning of an ecosystem. Understanding the mechanisms providing stability to these food webs is therefore vital for conservation efforts and the management of natural systems. Here, we first characterised a tropical stream meta-food web and five individual food webs using a Bayesian Hierarchical approach unifying three sources of information (gut content analysis, literature compilation and stable isotope data). With data on population-level biomass and individually measured body mass, we applied a bioenergetic model and assessed food web stability using a Lotka-Volterra system of equations. We then assessed the resilience of the system to individual species extinctions using simulations and investigated the network patterns associated with systems with higher stability. The model resulted in a stable meta-food web with 307 links among the 61 components. At the regional scale, 70% of the total energy flow occurred through a set of 10 taxa with large variation in body masses. The remaining 30% of total energy flow relied on 48 different taxa, supporting a significant dependency on a diverse community. The meta-food web was stable against individual species extinctions, with a higher resilience in food webs harbouring omnivorous fish species able to connect multiple food web compartments via weak, non-specialised interactions. Moreover, these fish species contributed largely to the spatial variation among individual food webs, suggesting that these species could operate as mobile predators connecting different streams and stabilising variability at the regional scale. Our results outline two key mechanisms of food web stability operating in tropical streams: (i) the diversity of species and body masses buffering against random and size-dependent disturbances and (ii) high regional diversity and weak omnivorous interactions of predators buffering against local stochastic variation in species composition. These mechanisms rely on high local and regional biodiversity in tropical streams, which is known to be strongly affected by human impacts. Therefore, an urgent challenge is to understand how the ongoing systematic loss of diversity jeopardises the stability of stream food webs in human-impacted landscapes.


As teias alimentares representam um emaranhado de interações tróficas associadas ao funcionamento de um ecossistema. Compreender os mecanismos que proporcionam estabilidade a estas teias alimentares é, portanto, vital para os esforços de conservação e gestão dos sistemas naturais. Aqui, primeiro caracterizamos uma meta teia alimentar de riachos tropicais e cinco teias alimentares individuais usando uma abordagem hierárquica Bayesiana unificando três fontes de informação (análise de conteúdo estomacal, compilação de literatura, dados de isótopos estáveis). Com dados sobre biomassa em nível populacional e massa corporal medida individualmente, aplicamos um modelo bioenergético e avaliamos a estabilidade da cadeia alimentar usando um sistema de equações Lotka­Volterra. Em seguida, avaliamos a resiliência do sistema às extinções de espécies individuais usando simulações e investigamos os padrões de rede associados a sistemas com maior estabilidade. O modelo resultou em uma meta teia alimentar estável com 307 ligações entre os 61 componentes. Na escala regional, 70% do fluxo total de energia ocorreu através de um conjunto de dez taxa com grande variação nas massas corporais. Os restantes 30% do fluxo total de energia dependiam de 47 taxa diferentes, apoiando uma dependência significativa de uma comunidade diversificada. A meta teia alimentar foi estável contra extinções de espécies individuais, com uma maior resiliência em teias alimentares que abrigam espécies de peixes onívoros capazes de conectar múltiplos compartimentos da teia alimentar através de interações fracas e não especializadas. Além disso, estas espécies de peixes contribuíram amplamente para a variação espacial entre as cadeias alimentares individuais, sugerindo que estas espécies poderiam operar como predadores móveis conectando diferentes riachos e estabilizando a variabilidade à escala regional. Nossos resultados descrevem dois mecanismos principais de estabilidade da cadeia alimentar operando em riachos tropicais: (i) a diversidade de espécies e massas corporais que protegem contra distúrbios aleatórios e dependentes do tamanho (ii) alta diversidade regional e fracas interações onívoras de predadores que protegem contra a variação estocástica local na composição de espécies. Estes mecanismos dependem de uma elevada biodiversidade local e regional em riachos tropicais, que são conhecidos por serem fortemente afetados pelos impactos humanos. Portanto, um desafio urgente é compreender como a contínua perda sistemática de diversidade põe em risco a estabilidade das teias alimentares em paisagens impactadas pelo homem.

3.
Knee Surg Sports Traumatol Arthrosc ; 32(8): 2003-2012, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38751091

RESUMEN

PURPOSE: The purpose of this study was to study the relationship between the presence of a deep lateral femoral notch sign (DLFNS) in anterior cruciate ligament (ACL)-injured patients and a higher posterior lateral tibial slope (LPTS), a reduced meniscal bone angle (MBA), a higher LPTS/MBA ratio and a higher incidence of concomitant injuries in primary ACL tears. METHODS: A retrospective case-control study was performed in patients submitted to primary ACL reconstruction with an available preoperative magnetic resonance imaging (MRI) scan. Patients with ACL tears and a femoral impactation with a depth ≥2 mm were assorted to the DLFNS group and patients with ACL tear and without a DLFNS to the control group. LPTS and MBA were measured in MRI. The presence of concomitant injuries (meniscal, posterior cruciate ligament, medial collateral ligament, lateral collateral ligament and bone injuries) was assessed in MRI. Quantitative data are presented in the median ± interquartile range (IQR). RESULTS: There were 206 patients included in the study, with 46 patients assorted to the DLFNS group and 160 patients to the control group. In the DLFNS group, the median LPTS was 6.7° (IQR: 4.0-8.2) versus 4.0° in the control group (IQR: 2.2-6.5) (p = 0.003). The LPTS/MBA ratio was significantly higher in the DLFNS group, with a median of 0.32 (IQR: 0.19-0.44), in comparison to the control group, with a median of 0.19 (IQR: 0.11-0.31) (p < 0.001). The multivariable logistic regression analysis showed that the LPTS is an independent risk factor to having a DLFNS (odds ratio [OR] = 1.161; 95% confidence interval [CI]: 1.042-1.293, p = 0.007). There was a higher incidence of concomitant lateral meniscal injuries in the DLFNS group (67% vs. 48%, p = 0.017). CONCLUSIONS: In patients with ACL tears, the presence of a DLFNS is associated with a steeper lateral posterior tibial slope, as well as a higher incidence of concomitant lateral meniscal injuries. LEVEL OF EVIDENCE: Level III.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Reconstrucción del Ligamento Cruzado Anterior , Fémur , Imagen por Resonancia Magnética , Tibia , Lesiones de Menisco Tibial , Humanos , Estudios Retrospectivos , Masculino , Femenino , Lesiones del Ligamento Cruzado Anterior/cirugía , Lesiones del Ligamento Cruzado Anterior/complicaciones , Lesiones del Ligamento Cruzado Anterior/diagnóstico por imagen , Adulto , Estudios de Casos y Controles , Fémur/diagnóstico por imagen , Tibia/diagnóstico por imagen , Lesiones de Menisco Tibial/diagnóstico por imagen , Lesiones de Menisco Tibial/cirugía , Adulto Joven , Adolescente , Meniscos Tibiales/diagnóstico por imagen , Meniscos Tibiales/cirugía
4.
Soft Matter ; 19(3): 394-409, 2023 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-36454226

RESUMEN

Low molecular weight gelators (LMWGs) are the subject of intense research for a range of biomedical and engineering applications. Peptides are a special class of LMWG, which offer infinite sequence possibilities and, therefore, engineered properties. This work examines the propensity of the GxG peptide family, where x denotes a guest residue, to self-assemble into fibril networks via changes in pH and ethanol concentration. These triggers for gelation are motivated by recent work on GHG and GAG, which unexpectedly self-assemble into centimeter long fibril networks with unique rheological properties. The propensity of GxG peptides to self-assemble, and the physical and chemical properties of the self-assembled structures are characterized by microscopy, spectroscopy, rheology, and X-ray diffraction. Interestingly, we show that the number, length, size, and morphology of the crystalline self-assembled aggregates depend significantly on the x-residue chemistry and the solution conditions, i.e. pH, temperature, peptide concentration, etc. The different x-residues allow us to probe the importance of different peptide interactions, e.g. π-π stacking, hydrogen bonding, and hydrophobicity, on the formation of fibrils. We conclude that fibril formation requires π-π stacking interactions in pure water, while hydrogen bonding can form fibrils in the presence of ethanol-water solutions. These results validate and support theoretical arguments on the propensity for self-assembly and leads to a better understanding of the relationship between peptide chemistry and fibril self-assembly. Overall, GxG peptides constitute a unique family of peptides, whose characterization will aid in advancing our understanding of self-assembly driving forces for fibril formation in peptide systems.


Asunto(s)
Glicina , Péptidos , Péptidos/química , Microscopía , Agua/química , Etanol
5.
Surg Today ; 53(10): 1181-1187, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37606758

RESUMEN

PURPOSE: Soft tissue sarcomas are rare malignant tumors. Liposarcoma constitutes the most frequent histological subtype of retroperitoneal sarcoma. The prognosis of soft tissue sarcomas depends on clinical and histologic characteristics. OBJECTIVE: Evaluate variables that may be related to the overall and local recurrence-free survival in patients with retroperitoneal liposarcoma and discuss the need for visceral resection en-bloc for tumors. METHODS: A retrospective analysis was conducted of the medical records of 60 patients seen between 1997 and 2017 who underwent surgical resection of retroperitoneal liposarcoma. RESULTS: The overall survival rate at 5 years of follow-up was 75.22% (95% confidence interval [CI] 0.58-0.86). The probability of a local recurrence-free survival at 5 years of follow-up was 26.04% (95% CI 0.11-0.44). The multivariate analysis showed that dedifferentiated or pleomorphic tumors and R2/fragmented resection were associated with a shorter time to recurrence. No other characteristics markedly influenced the overall survival (P > 0.05). CONCLUSION: Patients with dedifferentiated or pleomorphic tumors and incomplete resection were associated with higher local recurrence rates than others. This study reinforces the need for complete and en-bloc resection with organs when there is clear involvement or technical surgical difficulty to maintain the tumor integrity.


Asunto(s)
Liposarcoma , Neoplasias Retroperitoneales , Sarcoma , Humanos , Estudios Retrospectivos , Liposarcoma/cirugía , Liposarcoma/patología , Neoplasias Retroperitoneales/cirugía , Sarcoma/cirugía , Sarcoma/patología , Pronóstico , Tasa de Supervivencia , Recurrencia Local de Neoplasia
6.
Nano Lett ; 22(4): 1534-1540, 2022 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-35129361

RESUMEN

Moiré structures in small-angle-twisted bilayers of two-dimensional (2D) semiconductors with a broken-symmetry interface form arrays of ferroelectric (FE) domains with periodically alternating out-of-plane polarization. Here, we propose a network theory for the tunability of such FE domain structure by applying an electric field perpendicular to the 2D crystal. Using multiscale analysis, we derive a fully parametrized string-theory-like description of the domain wall network (DWN) and show that it undergoes a qualitative change, after the arcs of partial dislocation (PD) like domain walls merge (near the network nodes) into streaks of perfect screw dislocations (PSD), which happens at a threshold displacement field dependent on the DWN period.

7.
Neuroimage ; 249: 118854, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-34971767

RESUMEN

Canonical Correlation Analysis (CCA) and its regularised versions have been widely used in the neuroimaging community to uncover multivariate associations between two data modalities (e.g., brain imaging and behaviour). However, these methods have inherent limitations: (1) statistical inferences about the associations are often not robust; (2) the associations within each data modality are not modelled; (3) missing values need to be imputed or removed. Group Factor Analysis (GFA) is a hierarchical model that addresses the first two limitations by providing Bayesian inference and modelling modality-specific associations. Here, we propose an extension of GFA that handles missing data, and highlight that GFA can be used as a predictive model. We applied GFA to synthetic and real data consisting of brain connectivity and non-imaging measures from the Human Connectome Project (HCP). In synthetic data, GFA uncovered the underlying shared and specific factors and predicted correctly the non-observed data modalities in complete and incomplete data sets. In the HCP data, we identified four relevant shared factors, capturing associations between mood, alcohol and drug use, cognition, demographics and psychopathological measures and the default mode, frontoparietal control, dorsal and ventral networks and insula, as well as two factors describing associations within brain connectivity. In addition, GFA predicted a set of non-imaging measures from brain connectivity. These findings were consistent in complete and incomplete data sets, and replicated previous findings in the literature. GFA is a promising tool that can be used to uncover associations between and within multiple data modalities in benchmark datasets (such as, HCP), and easily extended to more complex models to solve more challenging tasks.


Asunto(s)
Conducta , Encéfalo , Conectoma/métodos , Red en Modo Predeterminado , Procesos Mentales , Modelos Teóricos , Red Nerviosa , Teorema de Bayes , Conducta/fisiología , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Conjuntos de Datos como Asunto , Red en Modo Predeterminado/diagnóstico por imagen , Red en Modo Predeterminado/fisiología , Análisis Factorial , Humanos , Imagen por Resonancia Magnética , Procesos Mentales/fisiología , Red Nerviosa/diagnóstico por imagen , Red Nerviosa/fisiología
8.
Cancer ; 128(24): 4223-4231, 2022 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-36274573

RESUMEN

BACKGROUND: Cutaneous squamous-cell carcinoma (CSCC) is among the most frequent malignancies worldwide. For those not amenable to treatment with curative intent, immune checkpoint inhibition (ICI) with anti-programmed death receptor 1 (PD-1) antibodies has emerged as a novel therapeutic option. In this study, the authors sought to investigate the activity of the anti-PD-1 agent nivolumab in patients with advanced CSCC (aCSCC). METHODS: CA209-9JC was an open-label, single-arm, phase 2 study to evaluate the safety and/or efficacy of nivolumab in systemic treatment-naive patients with aCSCC. Nivolumab (3 mg/kg) was administered every 2 weeks until disease progression, unacceptable toxicity, or 12 months of treatment. The primary end point was the best objective response rate (BORR) as per RECIST 1.1 criteria. Secondary end points included safety, progression-free survival (PFS), and overall survival (OS). RESULTS: Twenty-four patients with aCSCC were enrolled with a median age of 74 years (range, 48-93). Among the 24 patients evaluable for response, the BORR was 58.3% (14/24); there were no complete responses. With a median follow-up of 17.6 months, median duration of response has not been reached, and the estimated median PFS and OS were 12.7 and 20.7 months, respectively. Prior exposure to radiotherapy was associated with worse outcomes (p = .035, univariate analysis). Treatment-related adverse events of any grade and grade ≥ 3 occurred in 21 (87.5%) and six (25%) patients, respectively, and one patient discontinued nivolumab due to toxicities. CONCLUSIONS: Nivolumab resulted in robust antitumor activity, sustained responses, and good tolerability in systemic treatment-naive patients with aCSCC. These data provide further evidence to support the use of ICI as the standard treatment of aCSCC.


Asunto(s)
Carcinoma de Células Escamosas , Nivolumab , Humanos , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Nivolumab/efectos adversos , Carcinoma de Células Escamosas/inducido químicamente , Supervivencia sin Progresión , Criterios de Evaluación de Respuesta en Tumores Sólidos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico
9.
Stem Cells ; 39(9): 1207-1220, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33882146

RESUMEN

Although intracellular Wnt signaling pathways need to be tightly regulated to promote hematopoietic stem cell self-renewal, the source and identity of important Wnt ligands in the bone marrow is still largely unknown. The noncanonical ligand Wnt4 is expressed in the bone marrow as well as in the stroma, and its overexpression in fetal liver cells facilitates thymic recovery; however, its impact on adult hematopoietic stem cell function remains unclear. Here, we report that the deletion of Wnt4 from hematopoietic cells in mice (Wnt4Δ/Δ ) resulted in decreased lymphopoiesis at steady state. This was likely at least in part due to the increased proinflammatory environment present in the bone marrow of Wnt4Δ/Δ mice. Wnt4Δ/Δ hematopoietic stem cells displayed reduced reconstitution capacity in serial transplants, thus demonstrating defective self-renewal, and they expanded poorly in response to lipopolysaccharide stimulation. This appeared to be the result of the absence of Wnt4 in stem/progenitor cells, as myeloid-restricted Wnt4 deletion had no notable effect. Finally, we observed that Wnt4Δ/Δ stem/progenitor cells were more quiescent, presenting enhanced levels of stress-associated JNK phosphorylation and p16INK4a expression, likely contributing to the reduced expansion observed in transplants. In conclusion, our results identify a new, largely autocrine role for Wnt4 in hematopoietic stem cell self-renewal, suggesting that regulation of Wnt signaling in hematopoiesis may not need Wnt secretion and could be independent of morphogen gradients.


Asunto(s)
Hematopoyesis , Trasplante de Células Madre Hematopoyéticas , Animales , Diferenciación Celular , Autorrenovación de las Células , Células Madre Hematopoyéticas/metabolismo , Linfopoyesis , Ratones , Proteína Wnt4/genética , Proteína Wnt4/metabolismo
10.
Mol Psychiatry ; 26(5): 1445-1457, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-32103150

RESUMEN

TET3 is a member of the ten-eleven translocation (TET) family of enzymes which oxidize 5-methylcytosine (5mC) into 5-hydroxymethylcytosine (5hmC). Tet3 is highly expressed in the brain, where 5hmC levels are most abundant. In adult mice, we observed that TET3 is present in mature neurons and oligodendrocytes but is absent in astrocytes. To investigate the function of TET3 in adult postmitotic neurons, we crossed Tet3 floxed mice with a neuronal Cre-expressing mouse line, Camk2a-CreERT2, obtaining a Tet3 conditional KO (cKO) mouse line. Ablation of Tet3 in adult mature neurons resulted in increased anxiety-like behavior with concomitant hypercorticalism, and impaired hippocampal-dependent spatial orientation. Transcriptome and gene-specific expression analysis of the hippocampus showed dysregulation of genes involved in glucocorticoid signaling pathway (HPA axis) in the ventral hippocampus, whereas upregulation of immediate early genes was observed in both dorsal and ventral hippocampal areas. In addition, Tet3 cKO mice exhibit increased dendritic spine maturation in the ventral CA1 hippocampal subregion. Based on these observations, we suggest that TET3 is involved in molecular alterations that govern hippocampal-dependent functions. These results reveal a critical role for epigenetic modifications in modulating brain functions, opening new insights into the molecular basis of neurological disorders.


Asunto(s)
Ansiedad , Cognición , Dioxigenasas , Neuronas , Animales , Ansiedad/genética , Encéfalo/metabolismo , Metilación de ADN , Proteínas de Unión al ADN/genética , Dioxigenasas/genética , Dioxigenasas/metabolismo , Sistema Hipotálamo-Hipofisario/metabolismo , Ratones , Neuronas/metabolismo , Sistema Hipófiso-Suprarrenal/metabolismo
11.
Mycoses ; 64(9): 1062-1072, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34009677

RESUMEN

OBJECTIVES: To describe the first outbreak of Candida auris in Brazil, including epidemiological, clinical and microbiological data. METHODS: After the first Candida auris-colonised patient was diagnosed in a COVID-19 ICU at a hospital in Salvador, Brazil, a multidisciplinary team conducted a local C. auris prevalence investigation. Screening cultures for C. auris were collected from patients, healthcare workers and inanimate surfaces. Risk factors for C. auris colonisation were evaluated, and the fungemia episodes that occurred after the investigation were also analysed and described. Antifungal susceptibility of the C. auris isolates was determined, and they were genotyped with microsatellite analysis. RESULTS: Among body swabs collected from 47 patients, eight (n = 8/47, 17%) samples from the axillae were positive for C. auris. Among samples collected from inanimate surfaces, digital thermometers had the highest rate of positive cultures (n = 8/47, 17%). Antifungal susceptibility testing showed MICs of 0.5 to 1 mg/L for AMB, 0.03 to 0.06 mg/L for voriconazole, 2 to 4 mg/L for fluconazole and 0.03 to 0.06 mg/L for anidulafungin. Microsatellite analysis revealed that all C. auris isolates belong to the South Asian clade (Clade I) and had different genotypes. In multivariate analysis, having a colonised digital thermometer was the only independent risk factor associated with C. auris colonisation. Three episodes of C. auris fungemia occurred after the investigation, with 30-day attributable mortality of 33.3%. CONCLUSIONS: Emergence of C. auris in Salvador, Brazil, may be related to local C. auris clade I closely related genotypes. Contaminated axillary monitoring thermometers may facilitate the dissemination of C. auris reinforcing the concept that these reusable devices should be carefully cleaned with an effective disinfectant or replaced by other temperature monitoring methods.


Asunto(s)
Antifúngicos/uso terapéutico , Candida/efectos de los fármacos , Candidiasis/diagnóstico , Candidiasis/tratamiento farmacológico , Candidiasis/epidemiología , Transmisión de Enfermedad Infecciosa , Termómetros/microbiología , Adulto , Anciano , Anciano de 80 o más Años , Anidulafungina/uso terapéutico , Brasil/epidemiología , COVID-19/complicaciones , COVID-19/microbiología , Cuidados Críticos , Brotes de Enfermedades , Femenino , Fluconazol/uso terapéutico , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Prevalencia , SARS-CoV-2 , Voriconazol/uso terapéutico
12.
Reprod Domest Anim ; 56(7): 1034-1039, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33932236

RESUMEN

The aim of this study was to compare the biometric testicular characteristics, skin thickness and haemodynamics of the testicular artery of 12- and 24-month-old bulls using Doppler ultrasonography, the study was conducted using 48 indicus-taurus animals. The scrotal circumference (SC) and biometry characteristics of the bulls were measured to calculate the testicular volume. Doppler ultrasonography was used to obtain the haemodynamic values of the testicular artery. The skin thickness and volume were lower (p<.01) in the younger bulls (12 months:4.68 ± 0.68 mm; 168.76 ± 47.96 cm3 ) versus 24 months (5.05 ± 0.89; 499.73 ± 129.24 cm3 ) animals (p<.01). During diastole, mean velocity was lower in the 12 months (7.98 ± 3.83) than in the 24 months (11.37 ± 4.15) animals (p <.05). The 12-month-old animals had higher pulsatility and resistivity indices (0.49 ± 0.02; 0.51 ± 0.20) compared to the 24-month-old animals (0.32 ± 0.16; 0.40 ± 0.15) (p < .05). The final testicular end velocity was lower in animals with long/moderate-shaped (L/M) (7.31 ± 2.91) than in those moderate/oval-shaped (M/O) (11.48 ± 3.88) testicles (p < .05). Animals with L/M testes presented higher pulsatility values and resistivity indices (0.51 ± 0.05; 0.55 ± 0.04) compared to animals with M/O shape (0.29 ± 0.20; 0.36 ± 0.15). We showed that the blood flow of the supra testicular artery between the two evaluated ages differed, and that 24-month-old bulls presented better thermoregulation capacity. Animals with a long/moderate testicular format presented a greater vascular resistance, which was imposed on the blood flow due to the anatomical differences in the testicular artery, resulting in lower velocity, and indicating better heat dissipation in this format.


Asunto(s)
Velocidad del Flujo Sanguíneo , Testículo/anatomía & histología , Testículo/irrigación sanguínea , Factores de Edad , Animales , Regulación de la Temperatura Corporal , Bovinos , Masculino , Escroto/anatomía & histología , Piel/anatomía & histología , Testículo/diagnóstico por imagen , Testículo/fisiología , Ultrasonografía , Resistencia Vascular
13.
Chem Senses ; 45(8): 655-666, 2020 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-32968780

RESUMEN

Honeybees rely on nectar as their main source of carbohydrates. Sucrose, glucose, and fructose are the main components of plant nectars. Intriguingly, honeybees express only 3 putative sugar receptors (AmGr1, AmGr2, and AmGr3), which is in stark contrast to many other insects and vertebrates. The sugar receptors are only partially characterized. AmGr1 detects different sugars including sucrose and glucose. AmGr2 is assumed to act as a co-receptor only, while AmGr3 is assumedly a fructose receptor. We show that honeybee gustatory receptor AmGr3 is highly specialized for fructose perception when expressed in Xenopus oocytes. When we introduced nonsense mutations to the respective AmGr3 gene using CRISPR/Cas9 in eggs of female workers, the resulting mutants displayed almost a complete loss of responsiveness to fructose. In contrast, responses to sucrose were normal. Nonsense mutations introduced by CRISPR/Cas9 in honeybees can thus induce a measurable behavioral change and serve to characterize the function of taste receptors in vivo. CRISPR/Cas9 is an excellent novel tool for characterizing honeybee taste receptors in vivo. Biophysical receptor characterization in Xenopus oocytes and nonsense mutation of AmGr3 in honeybees unequivocally demonstrate that this receptor is highly specific for fructose.


Asunto(s)
Abejas/genética , Abejas/fisiología , Proteína 9 Asociada a CRISPR/metabolismo , Sistemas CRISPR-Cas , Mutagénesis , Mutación , Gusto/genética , Gusto/fisiología , Animales , Receptores Acoplados a Proteínas G/genética
14.
Surg Today ; 50(8): 855-862, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31950257

RESUMEN

PURPOSE: We analyzed the morbidity and mortality associated with Hartmann's reversal (HR) and the risk factors for major complications and mortality. METHODS: The subjects of this retrospective study were patients who underwent HR in a high-volume center. We evaluated complications as categorical variables using univariate analyses. RESULTS: Between 2003 and 2018, 199 patients underwent HR at our hospital [56.5 years; body mass index (BMI): 26.3 kg/m2; American Society of Anesthesiology score (ASA) 3: 7.5%; 36.2% had hernias]. The mean time to HR was 20.2 months and the mean operation time was 302 min. The anastomosis was stapled in 71.4% and was performed in the low/medium rectum in 21.6%. Midline hernias were repaired with mesh in 80.1%. The mean hospitalization period was 10.1 days. Surgical site infection (SSI) developed in 27.1% of the patients, 94.4% of whom were treated at the bedside. BMI was a risk factor for SSI (27.8 vs. 25.6; p = 0.047). Major complications (Clavien-Dindo III-V) developed in 27 patients (13.5%), including anastomosis dehiscence in 2.5%. ASA, BMI, age, hernia repair, and rectal stump size were not associated with major complications. The mortality rate was 2.5%. An ASA of 3 was associated with high mortality (p = 0.03). CONCLUSION: Hartmann's reversal remains challenging but can have low complication and mortality rates if performed on selected patients in a reference center. An ASA of 3 was the only predictor of mortality.


Asunto(s)
Colostomía/métodos , Complicaciones Posoperatorias/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Brasil , Colostomía/mortalidad , Femenino , Hospitales/estadística & datos numéricos , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Tempo Operativo , Selección de Paciente , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos , Factores de Riesgo , Dehiscencia de la Herida Operatoria/epidemiología , Dehiscencia de la Herida Operatoria/etiología , Infección de la Herida Quirúrgica/epidemiología , Infección de la Herida Quirúrgica/etiología , Adulto Joven
15.
Rep Pract Oncol Radiother ; 25(6): 919-926, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33088227

RESUMEN

AIM: To show three patients with soft tissue sarcomas of distal extremities conservatively treated after tumor-board discussion, involving margin-free surgery, exclusive intraoperative radiotherapy, and immediate reconstruction. BACKGROUND: Current guidelines show clear and robust recommendations regarding the composition of the treatment of sarcomas of extremities. However, little evidence exists regarding the application of these treatments depending on the location of the primary neoplasia. Tumors that affect the distal extremities present different challenges and make multidisciplinary discussions desirable. METHODS/RESULTS: We reported 3 patients who were approached with a conservative intention, after tumor board recomendation. The goals from the treatment performed were aesthetic and functional preservation, while enruring locoregional control. We had wound healing complications in 2 of the cases, requiring additional reconstruction measures. Patients are followed up for 24, 20 and 10 months; local control is 100%, and functional preservation is 100%. CONCLUSIONS: Despite being a small series, it was sufficient to illustrate successful multidisciplinary planning, generating a therapeutic result with improved quality of life for patients who had an initial indication for extremity amputation.

16.
J Transl Med ; 16(1): 45, 2018 02 27.
Artículo en Inglés | MEDLINE | ID: mdl-29486770

RESUMEN

BACKGROUND: Colorectal cancer (CRC) is one of the most incident cancers, associated with significant morbidity and mortality, and usually classified into three main molecular pathways: chromosomal instability, microsatellite instability (MSI) and CpG island methylator phenotype (CIMP). Currently, available screening methods are either costly or of limited specificity, impairing global implementation. More cost-effective strategies, including DNA methylation-based tests, might prove advantageous. Although some are already available, its performance is suboptimal, entailing the need for better candidate biomarkers. Herein, we tested whether combined use of APC, IGF2, MGMT, RASSF1A, and SEPT9 promoter methylation might accurately detect CRC irrespective of molecular subtype. METHODS: Selected genes were validated using formalin-fixed paraffin-embedded tissues from 214 CRC and 50 non-malignant colorectal mucosae (CRN). Promoter methylation levels were assessed using real-time quantitative methylation-specific PCR. MSI and CIMP status were determined. Molecular data were correlated with standard clinicopathological features. Diagnostic and prognostic performances were evaluated by receiver operator characteristics curve and survival analyses, respectively. RESULTS: Except for IGF2, promoter methylation levels were significantly higher in CRC compared to CRN. A three-gene panel (MGMT, RASSF1A, SEPT9) identified malignancy with 96.6% sensitivity, 74.0% specificity and 91.5 positive predictive value (area under the curve: 0.97), independently of tumor location, stage, and molecular pathway. CONCLUSIONS: Combined promoter methylation analysis of MGMT/RASSF1A/SEPT9 displays a better performance than currently available epigenetic-based biomarkers for CRC, providing the basis for the development of a non-invasive assay to detect CRC irrespective of the molecular pathway.


Asunto(s)
Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/genética , Metilación de ADN/genética , Transducción de Señal/genética , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/genética , Neoplasias Colorrectales/patología , Islas de CpG , Epigénesis Genética , Femenino , Humanos , Masculino , Inestabilidad de Microsatélites , Persona de Mediana Edad , Análisis Multivariante , Fenotipo , Regiones Promotoras Genéticas , Modelos de Riesgos Proporcionales , Curva ROC , Sensibilidad y Especificidad , Análisis de Supervivencia
17.
Int J Colorectal Dis ; 33(8): 1039-1045, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29675592

RESUMEN

PURPOSE: Patients with cancer of the lower and middle rectum who are candidates for curative surgery often have negative opinions on definitive colostomy. The purpose of this study is to compare the quality of life (QoL) of patients who undergo standard treatment for rectal cancer with sphincter preservation or definitive colostomy. METHODS: A total of 125 patients with adenocarcinoma of the lower or middle rectum who underwent radical surgery with curative intent with a follow-up ≥ 1 year were recruited: 83 patients (group 1) were subjected to low anterior resection and low colorectal or coloanal anastomosis-thus preserving their sphincter-and 42 (group 2) were treated with abdominoperineal resection, followed by terminal definitive colostomy. QoL was assessed with the EORTC QLQ-C30 and QLQ-CR29 questionnaires. RESULTS: Health and global quality of life were similar between groups; however, patients who underwent definitive colostomy had higher scores on the emotional (p value = 0.016) and cognitive function scales (p value = 0.017). Patients with sphincter preservation presented with more symptoms that were related to stool frequency (p value < 0.001), intestinal constipation (p value = 0.005), fecal incontinence (p value = 0.001), buttock pain (p value = 0.023), and nausea and vomiting (p value = 0.036), whereas patients with permanent colostomy had higher scores for dysuria (p value = 0.033). CONCLUSION: Although global QoL scores did not differ between groups, patients who underwent definitive colostomy had significantly better functional and symptom scale scores, reflecting greater function with fewer symptoms.


Asunto(s)
Colostomía , Calidad de Vida , Neoplasias del Recto/cirugía , Adolescente , Adulto , Anciano , Canal Anal , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad
18.
J Enzyme Inhib Med Chem ; 33(1): 1181-1193, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30044647

RESUMEN

In this study, we synthesized a new congener series of N-sulphonylhydrazones designed as candidate ROCK inhibitors using the molecular hybridization of the clinically approved drug fasudil (1) and the IKK-ß inhibitor LASSBio-1524 (2). Among the synthesized compounds, the N-methylated derivative 11 (LASSBio-2065) showed the best inhibitory profile for both ROCK isoforms, with IC50 values of 3.1 and 3.8 µM for ROCK1 and ROCK2, respectively. Moreover, these compounds were also active in the scratch assay performed in human breast cancer MDA-MB 231 cells and did not display toxicity in MTT and LDH assays. Molecular modelling studies provided insights into the possible binding modes of these N-sulphonylhydrazones, which present a new molecular architecture capable of being optimized and developed as therapeutically useful ROCK inhibitors.


Asunto(s)
Hidrazonas/química , Isoquinolinas/química , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/farmacología , Quinasas Asociadas a rho/antagonistas & inhibidores , 1-(5-Isoquinolinesulfonil)-2-Metilpiperazina/análogos & derivados , 1-(5-Isoquinolinesulfonil)-2-Metilpiperazina/química , 1-(5-Isoquinolinesulfonil)-2-Metilpiperazina/farmacología , Animales , Línea Celular Tumoral , Femenino , Humanos , Hidrazonas/síntesis química , Hidrazonas/farmacología , Modelos Moleculares , Difracción de Polvo , Análisis Espectral/métodos
19.
An Acad Bras Cienc ; 90(1 Suppl 2): 1073-1088, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29873669

RESUMEN

N-acylhydrazone is an interesting privileged structure that has been used in the molecular design of a myriad of bioactive compounds. In order to identify new antinociceptive drug candidates, we described herein the design, synthesis, X-ray diffraction study and the pharmacological evaluation of a series of 3-amino-4-methylthiophene-2-acylcarbohydrazone derivatives (8a-t). Compounds were prepared in good overall yields through divergent synthesis from a common key intermediate and were characterized by classical spectroscopy methods. X-ray diffraction study was employed for unequivocal determination of the imine double bond stereochemistry. 8a-t were evaluated in vivo through oral administration using the classical writhing test in mice. N-acylhydrazone derivatives 8j and 8l displayed relative potency similar to dipyrone, highlighting them as promising analgesic lead-candidates for further investigation.


Asunto(s)
Analgésicos/síntesis química , Antiinflamatorios/síntesis química , Hidrazonas/síntesis química , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores , Analgésicos/farmacología , Animales , Antiinflamatorios/farmacología , Diseño de Fármacos , Hidrazonas/farmacología , Espectrometría de Masas , Ratones , Difracción de Rayos X
20.
Angew Chem Int Ed Engl ; 57(31): 9970-9975, 2018 07 26.
Artículo en Inglés | MEDLINE | ID: mdl-29873877

RESUMEN

PIK-75 is a phosphoinositide-3-kinase (PI3K) α-isoform-selective inhibitor with high potency. Although published structure-activity relationship data show the importance of the NO2 and the Br substituents in PIK-75, none of the published studies could correctly determine the underlying reason for their importance. In this publication, we report the first X-ray crystal structure of PIK-75 in complex with the kinase GSK-3ß. The structure shows an unusual U-shaped conformation of PIK-75 within the active site of GSK-3ß that is likely stabilized by an atypical intramolecular Br⋅⋅⋅NO2 halogen bond. NMR and MD simulations show that this conformation presumably also exists in solution and leads to a binding-competent preorganization of the PIK-75 molecule, thus explaining its high potency. We therefore suggest that the site-specific incorporation of halogen bonds could be generally used to design conformationally restricted bioactive substances with increased potencies.

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