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1.
J Anim Ecol ; 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38847240

RESUMO

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.

2.
Rev Assoc Med Bras (1992) ; 70(suppl 1): e2024S109, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38865529

RESUMO

OBJECTIVE: In the emergency care of cancer patients, in addition to cancer-related factors, two aspects influence the outcome: (1) where the patient is treated and (2) who will perform the surgery. In Brazil, a significant proportion of patients with surgical oncological emergencies will be operated on in general hospitals by surgeons without training in oncological surgery. OBJECTIVE: The objective was to discuss quality indicators and propose the creation of an urgent oncological surgery advanced life support course. METHODS: Review of articles on the topic. RESULTS: Generally, nonelective resections are associated with higher rates of morbidity and mortality, as well as lower rates of cancer-specific survival. In comparison to elective procedures, the reduced number of harvested lymph nodes and the higher rate of positive margins suggest a compromised degree of radicality in the emergency scenario. CONCLUSION: Among modifiable factors is the training of the emergency surgeon. Enhancing the practice of oncological surgery in emergency settings constitutes a formidable undertaking that entails collaboration across various medical specialties and warrants endorsement and support from medical societies and educational institutions. It is time to establish a national registry encompassing oncological emergencies, develop quality indicators tailored to the national context, and foster the establishment of specialized training programs aimed at enhancing the proficiency of physicians serving in emergency services catering to cancer patients.


Assuntos
Neoplasias , Humanos , Neoplasias/cirurgia , Indicadores de Qualidade em Assistência à Saúde , Brasil , Oncologia Cirúrgica/normas , Oncologia Cirúrgica/educação , Emergências
3.
Invest New Drugs ; 42(3): 318-325, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38758478

RESUMO

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.


Assuntos
Estilbenos , Estilbenos/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Camundongos , Leucócitos Mononucleares/efeitos dos fármacos , Antineoplásicos/farmacologia , Humanos , Carcinoma de Ehrlich/tratamento farmacológico
4.
Artigo em Inglês | MEDLINE | ID: mdl-38751091

RESUMO

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.

5.
ACS Omega ; 9(1): 1748-1756, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38222663

RESUMO

Hybrid naphthalenediimide/zinc phosphonate materials (NDI/Zn) were prepared by mixing solutions of N,N'-bis(2-phosphonoethyl)-1,4,5,8-naphthalenediimide (PNDI) and zinc nitrate, resulting in the precipitation of the desired compounds. Samples precipitated from water and N,N-dimethylformamide (DMF) were produced. The obtained samples had the expected elemental composition, and the presence of naphthalenediimides (NDI) was ascertained by infrared and UV-visible spectroscopy. All the samples were crystalline, according to powder X-ray diffraction. Nitrogen adsorption isotherms showed the presence of porosity in the NDI/Zn samples. Mesopores with a diameter = 4.1 nm were present in the sample from DMF, with total pore volume reaching 0.13 cm3/g.

6.
ACS Appl Mater Interfaces ; 16(3): 4261-4270, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38217498

RESUMO

Layered lead halide perovskites have attracted much attention as promising materials for a new generation of optoelectronic devices. To make progress in applications, a full understanding of the basic properties is essential. Here, we study 2D-layered (BA)2PbX4 by using different halide anions (X = I, Br, and Cl) along with quantum confinement. The obtained cell parameter evolution, supported by experimental measurements and theoretical calculations, indicates strong lattice distortions of the metal halide octahedra, breaking the local inversion symmetry in (BA)2PbCl4, which strongly correlates with a pronounced Rashba spin-splitting effect. Optical measurements reveal strong photoluminescence quenching and a drastic reduction in the PL quantum yield in this larger band gap compound. We suggest that these optical results are closely related to the appearance of the Rashba effect due to the existence of a local electric dipole. The results obtained in ab initio calculations showed that the (BA)2PbCl4 possesses electrical polarization of 0.13 µC/cm2 and spin-splitting energy of about 40 meV. Our work establishes that local octahedra distortions induce Rashba spin splitting, which explains why obtaining UV-emitting materials with high PLQY is a big challenge.

7.
Rev. Assoc. Med. Bras. (1992, Impr.) ; 70(supl.1): e2024S109, 2024.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1558954

RESUMO

SUMMARY In the emergency care of cancer patients, in addition to cancer-related factors, two aspects influence the outcome: (1) where the patient is treated and (2) who will perform the surgery. In Brazil, a significant proportion of patients with surgical oncological emergencies will be operated on in general hospitals by surgeons without training in oncological surgery. OBJECTIVE: The objective was to discuss quality indicators and propose the creation of an urgent oncological surgery advanced life support course. METHODS: Review of articles on the topic. RESULTS: Generally, nonelective resections are associated with higher rates of morbidity and mortality, as well as lower rates of cancer-specific survival. In comparison to elective procedures, the reduced number of harvested lymph nodes and the higher rate of positive margins suggest a compromised degree of radicality in the emergency scenario. CONCLUSION: Among modifiable factors is the training of the emergency surgeon. Enhancing the practice of oncological surgery in emergency settings constitutes a formidable undertaking that entails collaboration across various medical specialties and warrants endorsement and support from medical societies and educational institutions. It is time to establish a national registry encompassing oncological emergencies, develop quality indicators tailored to the national context, and foster the establishment of specialized training programs aimed at enhancing the proficiency of physicians serving in emergency services catering to cancer patients.

8.
Plants (Basel) ; 12(23)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38068686

RESUMO

The simultaneous analysis of the maximum number of chemical elements present in plant tissues provides more comprehensive information about their chemical constitution and increases the number of characteristics for the selection process in various plant breeding programs. The objective of this study was to analyze productivity, grain yield, and concentration of chemical elements in tissues of Coffea canephora clones to study phenotypic diversity and estimate genetic parameters for use in breeding. This experiment was carried out in Manaus, Amazonas, Brazil, in randomized blocks with four replications. The concentrations of elements in various organs were quantified using total reflection X-ray fluorescence (TXRF). Genetic parameters and genetic divergence were estimated, and genotypes were clustered using the UPGMA hierarchical method and non-metric multidimensional scaling analysis. The study allowed us to differentiate the performance of the clones in terms of the absorption of essential and non-essential chemical elements for plant development and to analyze the correlation of the characteristics in the selection process. TXRF efficiently characterizes the presence and concentration of multiple elements, aiding genotype discrimination for C. canephora improvement.

9.
Surg Today ; 53(10): 1181-1187, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37606758

RESUMO

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.


Assuntos
Lipossarcoma , Neoplasias Retroperitoneais , Sarcoma , Humanos , Estudos Retrospectivos , Lipossarcoma/cirurgia , Lipossarcoma/patologia , Neoplasias Retroperitoneais/cirurgia , Sarcoma/cirurgia , Sarcoma/patologia , Prognóstico , Taxa de Sobrevida , Recidiva Local de Neoplasia
10.
Acta bioeth ; 29(1): 91-100, jun. 2023. tab, ilus
Artigo em Português | LILACS | ID: biblio-1439083

RESUMO

O presente estudo trata-se de uma análise na literatura sobre o aspecto bioético da autonomia em relação a imunização contra Hepatite B e HPV na adolescência. Foi realizada uma revisão bibliográfica baseada no método prisma onde foram incluídos artigos em português e inglês os quais foram pesquisados nas plataformas Scientific Electronic Library Online (SciELO), Literatura Latino-Americana e do Caribe em Ciências da Saúde (LILACS) e National Library of Medicine (PUBMED), utilizando os seguintes descritores Hepatitis B Vaccines, bioethics, Humans. Os resultados demostraram a eficiência dos profissionais de saúde no contato com o indivíduo e o convencimento deste através de um diálogo aberto e criação de vínculos. Evidenciou-se ainda o estudo evidenciou o direito a autonomia progressiva do paciente, no qual este ganha o direito a algumas escolhas como as imunizações de doenças sexualmente transmissíveis, como é o caso da Hepatite B e HPV, no entanto é necessário que o adolescente seja instruído sobre a imunização. Assim sendo, reconhece-se o direito a autonomia progressiva do adolescente, referente a escolha das imunizações contra a Hepatite B e HPV, entretanto, deve-se considerar que estes indivíduos sejam instruídos sobre os benefícios individuais e/ou coletivos da vacinação, contemplados por atividades de educação em saúde por profissionais qualificados, objetivando ampliar a cobertura global de imunização com doenças que caracterizam problemas de saúde pública.


El presente estudio es un análisis de la literatura sobre el aspecto bioético de la autonomía en relación con la inmunización contra la Hepatitis B y el VPH en la adolescencia. Se realizó una revisión bibliográfica basada en el método del prisma, que incluyó artículos en portugués e inglés que fueron buscados en la Biblioteca Científica Electrónica en Línea (SciELO), Literatura Latinoamericana y del Caribe en Ciencias de la Salud (LILACS) y la Biblioteca Nacional de Medicina (PUBMED), utilizando los siguientes descriptores Vacunas Hepatitis B, bioética, Humanos. Los resultados demostraron la eficiencia de los profesionales de la salud en contactar al individuo y convencerlo a través de un diálogo abierto y creación de vínculos. También se evidenció que el estudio evidenció el derecho del paciente a la autonomía progresiva, en la que adquiere el derecho a algunas opciones como las inmunizaciones de enfermedades de transmisión sexual, como la Hepatitis B y el VPH, sin embargo, es necesario que el adolescente sea educado sobre la inmunización. Por lo tanto, se reconoce el derecho del adolescente a la autonomía progresiva, en cuanto a la elección de las vacunas contra la Hepatitis B y el VPH, sin embargo, se debe considerar que estos individuos sean educados sobre los beneficios individuales y/o colectivos de la vacunación, contemplados por las actividades de educación en salud por profesionales calificados, con el objetivo de ampliar la cobertura mundial de inmunización con enfermedades que caracterizan los problemas de salud pública.


The present study is an analysis of the literature on the bioethical aspect of autonomy in relation to immunization against Hepatitis B and HPV in adolescence. A bibliographic review was carried out based on the prism method, which included articles in Portuguese and English which were searched on the Scientific Electronic Library Online (SCIELO), Latin American and Caribbean Literature on Health Sciences (LILACS) and the National Library of Medicine (PUBMED), using the following descriptors Hepatitis B Vaccines, bioethics, Humans. The results demonstrated the efficiency of health professionals in contacting the individual and convincing him/her through an open dialogue and creation of bonds. It was also evidenced the study evidenced the patient's right to progressive autonomy, in which he gains the right to some choices such as immunizations of sexually transmitted diseases, such as Hepatitis B and HPV, however it is necessary for the adolescent to be educated about immunization. Therefore, the adolescent's right to progressive autonomy is recognized, regarding the choice of immunizations against Hepatitis B and HPV, however, it must be considered that these individuals are instructed on the individual and/or collective benefits of vaccination, contemplated by health education activities by qualified professionals, aiming to expand the global coverage of immunization with diseases that characterize public health problems.


Assuntos
Humanos
11.
Acta bioeth ; 29(1): 101-112, jun. 2023. tab, graf
Artigo em Português | LILACS | ID: biblio-1439067

RESUMO

O estudo investiga os aspectos epidemiológicos da hepatite B em crianças e adolescentes, discutindo os resultados encontrados à luz dos princípios da bioética. Trata-se de um estudo transversal, retrospectivo, com base em uma série temporal de casos, cujos dados de notificação foram extraídos do Sistema de Informação de Agravos de Notificação (SINAN) e dados de vacinação do Sistema de Informação do Programa Nacional de Imunizações - SIPNI, no período de 2011 a 2020. Foram notificados 889 casos de hepatite B na população de estudo. A maioria dos participantes encontravam-se na faixa etária de 15 a 19 anos 738 (83%), do sexo feminino 549 (62%), cor da pele parda 637 (72%) residentes na zona urbana 490 (55%) e com ensino fundamental incompleto 279 (31%). A provável fonte de infecção foi por via sexual 450 (51%). A forma clínica mais comum foi a Hepatite Crônica 496 (56%). A maioria dos contaminados com Hepatite B foram indivíduos não vacinados 298 (34%). A luz da bioética os resultados demostram que a prática da vacinação pode contemplar os princípios bioéticos, já que o grau de autonomia depende de um tipo de intervenção planejada e quanto maior a relação entre benefício e ônus, tendo em conta os princípios de beneficência e não maleficência, menos decisiva é essa autonomia.


El estudio investiga los aspectos epidemiológicos de la hepatitis B en niños y adolescentes, discutiendo los resultados encontrados a la luz de los principios bioéticos. Se trata de un estudio transversal, retrospectivo, basado en una serie temporal de casos, cuyos datos de notificación fueron extraídos del Sistema de Información de Enfermedades de Declaración Obligatoria (SINAN) y datos de vacunación del Sistema de Información del Programa Nacional de Inmunizaciones SIPNI, desde 2011 hasta 2020. Se informaron 889 casos de hepatitis B en la población de estudio. La mayoría de los participantes tenían entre 15 y 19 años 738 (83 %), sexo femenino 549 (62 %), color de piel morena 637 (72 %), residentes en zona urbana 490 (55 ) y con educación primaria incompleta 279 (31 %). La fuente probable de infección fue a través de relaciones sexuales 450 (51%). La forma clínica más frecuente fue la Hepatitis Crónica 496 (56%). La mayoría de los infectados con Hepatitis B eran individuos no vacunados 298 (34%). A la luz de la bioética, los resultados muestran que la práctica de la vacunación puede contemplar principios bioéticos, ya que el grado de autonomía depende de un tipo de intervención planificada y mayor la relación entre beneficio y carga, teniendo en cuenta los principios de beneficencia y no maleficencia, menos decisiva es esta autonomía.


The study investigates the epidemiological aspects of hepatitis B in children and adolescents, discussing the results found in the light of bioethical principles. This is a cross-sectional, retrospective study, based on a time series of cases, whose notification data were extracted from the Notifiable Diseases Information System (SINAN) and vaccination data from the National Immunization Program Information System SIPNI, from 2011 to 2020. 889 cases of hepatitis B were reported in the study population. Most participants were aged between 15 and 19 years old 738 (83%), female 549 (62%), brown skin color 637 (72%) living in the urban area 490 (55%) and with incomplete elementary education 279 (31%). The probable source of infection was through sexual intercourse 450 (51%). The most common clinical form was Chronic Hepatitis 496 (56%). Most of those infected with Hepatitis B were unvaccinated individuals 298 (34%). In the light of bioethics, the results show that the practice of vaccination can contemplate bioethical principles, since the degree of autonomy depends on a type of planned intervention and the greater the relationship between benefit and burden, taking into account the principles of beneficence and not maleficence, the less decisive is this autonomy.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Brasil , Estudos Transversais
12.
Arq Bras Cir Dig ; 36: e1729, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37194861

RESUMO

BACKGROUND: Colorectal cancer (CRC) is a worldwide health problem whose control depends on public policy establishment and effective prevention and screening programs. In Brazil, there are few studies related to adherence to screening methods. AIMS: The aim of this study was to evaluate the association between demographic and socioeconomic to adherence to CRC screening with fecal immunochemical test (FIT) among average-risk individuals for CRC. METHODS: In this prospective cross-sectional study, conducted between March 2015 and April 2016, 1,254 asymptomatic individuals aged 50-75 years, participating in a hospital screening campaign in Brazil, were invited to participate in the study. RESULTS: The adherence rate to FIT was 55.6% (697/1,254). In the multivariable logistic regression analysis, patients aged 60-75 years (odds ratio (OR)=1.30; 95% confidence interval (CI): 1.02-1.66; p=0.03), religious belief (OR=2.04; 95% CI: 1.34-3.11; p<0.01), previous fecal occult blood test (OR=2.07; 95% CI: 1.55-2.76; p<0.01), and full/part-time working status (OR=0.66; 95% CI: 0.49-0.89; p<0.01) were independently associated with adherence to CRC screening. CONCLUSION: The results of the present study highlight the importance of considering the labor aspects when implementing screening programs, suggesting that campaigns conducted in the workplace and repeated over the years may be more effective.


Assuntos
Neoplasias Colorretais , Detecção Precoce de Câncer , Humanos , Detecção Precoce de Câncer/métodos , Estudos Transversais , Estudos Prospectivos , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/prevenção & controle , Sangue Oculto , Colonoscopia
14.
Soft Matter ; 19(3): 394-409, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36454226

RESUMO

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.


Assuntos
Glicina , Peptídeos , Peptídeos/química , Microscopia , Água/química , Etanol
15.
ABCD (São Paulo, Online) ; 36: e1729, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1439002

RESUMO

ABSTRACT BACKGROUND Colorectal cancer (CRC) is a worldwide health problem whose control depends on public policy establishment and effective prevention and screening programs. In Brazil, there are few studies related to adherence to screening methods. AIMS: The aim of this study was to evaluate the association between demographic and socioeconomic to adherence to CRC screening with fecal immunochemical test (FIT) among average-risk individuals for CRC. METHODS: In this prospective cross-sectional study, conducted between March 2015 and April 2016, 1,254 asymptomatic individuals aged 50-75 years, participating in a hospital screening campaign in Brazil, were invited to participate in the study. RESULTS: The adherence rate to FIT was 55.6% (697/1,254). In the multivariable logistic regression analysis, patients aged 60-75 years (odds ratio (OR)=1.30; 95% confidence interval (CI): 1.02-1.66; p=0.03), religious belief (OR=2.04; 95% CI: 1.34-3.11; p<0.01), previous fecal occult blood test (OR=2.07; 95% CI: 1.55-2.76; p<0.01), and full/part-time working status (OR=0.66; 95% CI: 0.49-0.89; p<0.01) were independently associated with adherence to CRC screening. CONCLUSION: The results of the present study highlight the importance of considering the labor aspects when implementing screening programs, suggesting that campaigns conducted in the workplace and repeated over the years may be more effective.


RESUMO RACIONAL: O câncer colorretal (CCR) é um problema de saúde mundial cujo controle depende do estabelecimento de políticas públicas e programas de prevenção e rastreamento eficazes. No Brasil existem poucos estudos relacionados à adesão métodos de rastreamento. OBJETIVO: Avaliar a associação de características sócio-demográficas à realização de testes de sangue oculto nas fezes do tipo imunoquimicomecanizado (FIM) em população de médio risco para o desenvolvimento de câncer colorretal. MÉTODOS: Estudo observacional transversal, com coleta prospectiva de dados. Entre março de 2015 e abril de 2016, 1.254 indivíduos assintomáticos, com idade entre 50 e 75 anos, foram consecutivamente selecionados a partir de uma campanha hospitalar de rastreamento para neoplasias. RESULTADOS: As taxas de adesão ao teste FIM foi 55.6% (697/1254). Na análise de regressão logística múltipla os fatores independentes associados à adesão ao rastreamento do CCR foram: Idade entre 60-75 anos (oddsratio (OR)=1.30; intervalo de confiança de 95% (IC): 1.02-1.66; p=0.03), crença religiosa (OR=2.04; 95%IC: 1.34-3.11; p<0.01), realização prévia de exame de sangue oculto nas fezes (OR=2.07; 95%IC: 1.55-2.76; p<0.01) e vínculo empregatício em período integral ou parcial (OR=0.66; 95%IC: 0.49-0.89; p<0.01). CONCLUSÃO: Este estudo enfatiza a importância de considerar aspectos laborais ao implementar programas de rastreamento do câncer colorretal e sugere que campanhas de rastreamento implantadas no ambiente de trabalho e de maneira repetida ao longo dos anos podem ser mais efetivas.

16.
Rio de Janeiro; s.n; 2023. 150 f p. il..
Tese em Português | LILACS | ID: biblio-1438441

RESUMO

As mudanças epidemiológicas e demográficas impactam diretamente no aumento das doenças crônicas não transmissíveis e na demanda por cuidados em saúde cada vez mais complexos que englobam a tomada de decisão de forma multidisciplinar e compartilhada entre equipe, família e paciente. Portanto o objeto desta pesquisa foi a visão do aluno da residência multiprofissional a respeito das decisões terapêuticas com pacientes em fim de vida tendo como pano de fundo a bioética por princípios de Beauchamp e Childress. Os objetivos foram: descrever, através do discurso do aluno da residência multiprofissional, como se dá o processo de tomada de decisões terapêuticas com pacientes em fim de vida e quais respaldos morais e bioéticos são utilizados nestas decisões; identificar, a partir do discurso do residente multidisciplinar, a participação dos profissionais da saúde, da família/cuidadores e do próprio paciente nas decisões terapêuticas do fim da vida. Trata-se de uma pesquisa qualitativa, descritiva e exploratória, realizada com 25 alunos de três programas de residência multiprofissional do município do Rio de Janeiro. A técnica para coleta dos dados baseou-se em entrevista semiestruturada realizada no período de 15/07 à 20/09/2022. O método para obtenção dos participantes foi o de bola de neve (snow ball) onde o primeiro participante é escolhido aleatoriamente e os demais são indicados pelo antecessor. Foram observados todos os critérios éticos em pesquisa da Resolução 466/2012 do Ministério da Saúde. Para o tratamento dos dados foi utilizada a análise categorial de Denize Oliveira. Ao final da categorização emergiram três categorias: "Processo de tomada de decisão com pacientes em fim da vida", "Princípios éticos norteadores da tomada de decisão" e "O mundo ideal e o mundo real do processo de tomada de decisão". A primeira categoria buscou detalhar o processo de tomada de decisão com pacientes no fim da vida mostrando a centralização da tomada de decisão, a tomada de decisão de forma multidisciplinar e de forma compartilhada com paciente e família. A segunda categoria relacionou o processo de tomada de decisão com pacientes no fim da vida aos princípios bioéticos de Beaucahmp e Childress demonstrando de forma individualizada a utilização destes para a personalização da tomada de decisão. A terceira categoria apontou os pontos que os residentes entendiam como ideais para o processo de tomada de decisão e as questões relacionadas ao que realmente acontece na prática clínica do dia a dia permeada pelas dificuldades estruturais, sociais e acadêmicas que interferem neste processo. Conclui-se que estamos ainda distantes de um modelo ideal de processo de tomada de decisão que ainda se apresenta de forma médicocentrada, verticalizada e pouco compartilhada com família e pacientes. AU


Epidemiological and demographic changes directly impact the increase in non-communicable chronic diseases and the demand for increasingly complex healthcare, which involves multidisciplinary and shared decision-making among the team, family, and patient. Therefore, the objective of this research was to explore the perspective of residents regarding therapeutic decisions with end-of-life patients, framed within the principles of Beauchamp and Childress' bioethics. The specific aims were to describe, through the discourse of multidisciplinary residents, the process of making therapeutic decisions with end-of-life patients and the moral and bioethical foundations guiding these decisions, as well as to identify the involvement of healthcare professionals, family/caregivers, and the patients themselves in end-of-life therapeutic decisions. This qualitative, descriptive, and exploratory research was conducted with 25 residents from three multidisciplinary residency programs in the city of Rio de Janeiro. Data collection was based on semi-structured interviews conducted from July 15th to September 20th, 2022. The snowball sampling method was used to select participants, where the first participant is chosen randomly and subsequent participants are referred by the preceding ones. The ethical criteria outlined in Resolution 466/2012 of the Ministry of Health were observed throughout the research process. Data analysis was performed using Denize Oliveira's categorical analysis. Three categories emerged from the analysis: "Process of decision-making with end-of-life patients," "Ethical principles guiding decision-making," and "The ideal world and the real world of the decision-making process." The first category aimed to detail the decision-making process with end-of-life patients, highlighting the centralization of decision-making, multidisciplinary decision-making, and shared decision-making with patients and their families. The second category linked the decision-making process with end-of-life patients to Beauchamp and Childress' bioethical principles, demonstrating their individualized application to personalize decision-making. The third category identified the aspects that residents perceived as ideal for the decision-making process, as well as the challenges encountered in the clinical practice influenced by structural, social, and academic difficulties. The findings suggest that we are still far from an ideal model of decision-making, as it remains predominantly physician-centered, hierarchical, and lacking in shared decision-making with families and patients. AU


Assuntos
Humanos , Equipe de Assistência ao Paciente , Cuidados Paliativos na Terminalidade da Vida , Tomada de Decisão Clínica , Internato e Residência , Sistema Único de Saúde , Bioética , Brasil
17.
Arthrosc Sports Med Rehabil ; 4(6): e1993-e2003, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36579050

RESUMO

Purpose: To evaluate the influence of lateral posterior tibial slope (LPTS) and meniscal bone angle (MBA) on primary anterior cruciate ligament (ACL) tear risk in an adult population through the LPTS-MBA ratio. Methods: A retrospective case-control study was performed with patients from a tertiary hospital who underwent primary ACL surgery and had preoperative magnetic resonance imaging (MRI). These subjects were matched by age and sex in a 1:1 ratio to patients who had an MRI without ACL tear. LPTS and MBA were measured on MRI scan. Quantitative data are presented in the median ± interquartile range (IQR). Identification of independent risk factors for primary ACL tear was performed using multivariable logistic regression. Receiver operating characteristics curves detected any variable with strong discriminative capacity. Results: In total, 95 patients with primary ACL tear confirmed on MRI were matched with 95 controls (N = 190). Nearly 80% were male subjects, with a median age of 26 years. In the ACL tear group, the median value of LPTS-MBA ratio was 0.20 (IQR 0.11-0.37) versus 0.12 (IQR 0.08-0.19) in the control group (P = .001). LPTS had a median value of 4.20° in the ACL tear group (IQR 2.05-7.35°) and 2.90° in the control group (IQR, 2.05-5.00°) (P = .026), whereas MBA was 19° (IQR, 16-24°) versus 26° (IQR, 24-30°) (P = .001), respectively. Logistic regression showed that LPTS (odds ratio 1.20, 95% confidence interval 1.03-1.42, P = .021) and MBA (odds ratio 0.78, 95% confidence interval 0.71-0.85, P = .001) were independent predictors. The area under the curve (AUC) of LPTS-MBA ratio was 0.69, greater than that of LPTS alone (AUC = 0.61) but lower than that for MBA (AUC = 0.82). Conclusions: In this study, a reduced MBA was the strongest predictive variable associated with a primary ACL tear. A threshold of 22.35° of MBA was associated with an increased risk of ACL tear, with a sensitivity of 70% and specificity of 84%. A cut-off of 0.22 of LPTS-MBA was associated with an increased risk of ACL tear, with a sensitivity of 55% and specificity of 87%. Level of Evidence: Level III, case-control study.

18.
Commun Biol ; 5(1): 1297, 2022 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-36435870

RESUMO

Identifying associations between interindividual variability in brain structure and behaviour requires large cohorts, multivariate methods, out-of-sample validation and, ideally, out-of-cohort replication. Moreover, the influence of nature vs nurture on brain-behaviour associations should be analysed. We analysed associations between brain structure (grey matter volume, cortical thickness, and surface area) and behaviour (spanning cognition, emotion, and alertness) using regularized canonical correlation analysis and a machine learning framework that tests the generalisability and stability of such associations. The replicability of brain-behaviour associations was assessed in two large, independent cohorts. The load of genetic factors on these associations was analysed with heritability and genetic correlation. We found one heritable and replicable latent dimension linking cognitive-control/executive-functions and positive affect to brain structural variability in areas typically associated with higher cognitive functions, and with areas typically associated with sensorimotor functions. These results revealed a major axis of interindividual behavioural variability linking to a whole-brain structural pattern.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Humanos , Encéfalo/diagnóstico por imagem , Substância Cinzenta , Cognição , Função Executiva
19.
Cancer ; 128(24): 4223-4231, 2022 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-36274573

RESUMO

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.


Assuntos
Carcinoma de Células Escamosas , Nivolumabe , Humanos , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Nivolumabe/efeitos adversos , Carcinoma de Células Escamosas/induzido quimicamente , Intervalo Livre de Progressão , Critérios de Avaliação de Resposta em Tumores Sólidos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
20.
J Belg Soc Radiol ; 106(1): 78, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36213372

RESUMO

Inflammatory myofibroblastic tumors have a wide spectrum of biological behaviour and are composed of inflammatory cells and myofibroblastic spindle cells. Tumors may infrequently involve the liver. Imaging findings are non-specific. Teaching Point: Radiologists should be familiar with inflammatory myofibroblastic tumors as a diagnostic consideration to avoid unnecessary surgery.

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