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1.
Clin J Sport Med ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38917297

RESUMO

OBJECTIVES: This study explored the link between early sports specialization and injury rates in youth divers, a relationship that remains largely unexplored within diving. DESIGN: Cross-sectional survey. SETTING: Members of the USA Diving Organization and collegiate male and female divers participated in an online survey, reporting their sports involvement and injury history. PARTICIPANTS: One hundred eighty-two male and female divers aged 8 to 25 years were recruited through USA Diving or US collegiate team databases. INDEPENDENT VARIABLES: Early/late specialization (based on age <12 or 12 years or older), gender (M/F), springboard and/or platform divers, experience (junior/senior, regional/zone/national/international), hours of dryland/water training, and prior sport exposure. MAIN OUTCOME MEASURES: Injury history obtained on questionnaire. RESULTS: One hundred eighty-two divers were surveyed; 70% female. Age to start diving and age to concentrate solely on diving were significantly associated with certain injuries (P < 0.05). Beginning diving before age 13 years of age was significantly associated with lower odds of injuries in the shoulder and wrist (P = 0.013 and 0.018, respectively), after adjusting for select covariates. Age of specialization was not significantly associated with injuries in any body part (P > 0.05), after adjusting for covariates. Greater years of diving experience was significantly associated with diving injuries in all 11 body parts (P < 0.05). CONCLUSIONS: This study indicates that early sports specialization is associated with decreased injury rates in elite youth divers who specialized before age 13 years, particularly for head/neck, shoulder, and wrist injuries. Moreover, we observed a positive correlation between experience and injury rate. Further investigation should focus on distinguishing between acute and overuse injuries.

2.
J Immunother Cancer ; 12(1)2024 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-38212126

RESUMO

BACKGROUND: The C-C motif chemokine receptor 5 (CCR5)/C-C motif chemokine ligand 5 (CCL5) axis plays a major role in colorectal cancer (CRC). We aimed to characterize the molecular features associated with CCR5/CCL5 expression in CRC and to determine whether CCR5/CCL5 levels could impact treatment outcomes. METHODS: 7604 CRCs tested with NextGen Sequencing on DNA and RNA were analyzed. Molecular features were evaluated according to CCR5 and CCL5 tumor gene expression quartiles. The impact on treatment outcomes was assessed in two cohorts, including 6341 real-world patients and 429 patients from the Cancer and Leukemia Group B (CALGB)/SWOG 80405 trial. RESULTS: CCR5/CCL5 expression was higher in right-sided versus left-sided tumors, and positively associated with consensus molecular subtypes 1 and 4. Higher CCR5/CCL5 expression was associated with higher tumor mutational burden, deficiency in mismatch repair and programmed cell death ligand 1 (PD-L1) levels. Additionally, high CCR5/CCL5 were associated with higher immune cell infiltration in the tumor microenvironment (TME) of MMR proficient tumors. Ingenuity pathway analysis revealed upregulation of the programmed cell death protein 1 (PD-1)/PD-L1 cancer immunotherapy pathway, phosphatase and tensin homolog (PTEN) and peroxisome proliferator-activated receptors (PPAR) signaling, and cytotoxic T-lymphocyte antigen 4 (CTLA-4) signaling in cytotoxic T lymphocytes, whereas several inflammation-related pathways were downregulated. Low CCR5/CCL5 expression was associated with increased benefit from cetuximab-FOLFOX treatment in the CALGB/SWOG 80405 trial, where significant treatment interaction was observed with biologic agents and chemotherapy backbone. CONCLUSIONS: Our data show a strong association between CCR5/CCL5 gene expression and distinct molecular features, gene expression profiles, TME cell infiltration, and treatment benefit in CRC. Targeting the CCR5/CCL5 axis may have clinical applications in selected CRC subgroups and may play a key role in developing and deploying strategies to modulate the immune TME for CRC treatment.


Assuntos
Neoplasias Colorretais , Receptores de Quimiocinas , Humanos , Antígeno B7-H1/genética , Ligantes , Quimiocina CCL5/genética , Quimiocina CCL5/metabolismo , Quimiocinas/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Expressão Gênica , Microambiente Tumoral , Receptores CCR5/genética , Receptores CCR5/metabolismo
3.
BMC Pregnancy Childbirth ; 23(1): 435, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37312055

RESUMO

BACKGROUND: The aim of the present paper was to explore the role of partners for the stressful life events of birth and the transition to parenthood. METHODS: In a first prospective longitudinal study (N = 304 dyads) we tested whether relationship quality positively predicted fewer interventions during labor and birth, a more positive birth experience, and better well-being during the first six weeks after birth. In a second study we surveyed mothers (N = 980; retrospective quasi-experimental design) who had given birth during the first lockdown of the COVID-19 pandemic in spring 2020 - some in the absence of their partners - to test the assumption that regardless of relationship quality, the presence of the partner was positively related to low-intervention births and the birth experience. RESULTS: The results of the longitudinal study (Study 1) could be integrated into a Single Indicator model. They revealed that a high relationship quality assessed between week 5 and week 25 of pregnancy had a positive effect on birth experience for the mother and on psychological well-being during the transition to parenthood for both mothers and fathers. Results of the retrospective quasi-experimental field study (Study 2) revealed that the continuous presence of the partner was associated with a higher probability of a low-intervention birth and a more positive birth experience. Presence of a partner for only part of the birth did not positively predict labor and birth, but did positively predict the birth experience. The effects were independent of relationship quality. CONCLUSION: The results of both studies highlight the importance of partners for psychological well-being during labor and birth and the transition to parenthood.


Assuntos
COVID-19 , Pandemias , Feminino , Humanos , Gravidez , Controle de Doenças Transmissíveis , COVID-19/epidemiologia , Estudos Longitudinais , Estudos Prospectivos , Estudos Retrospectivos , Apoio Social , Pais
4.
J Pediatr ; 259: 113419, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37044372

RESUMO

OBJECTIVES: To evaluate implementation of rifamycin-based regimens (RBR) for pediatric tuberculosis infection (TBI) treatment among 3 provider settings in a high-incidence county. STUDY DESIGN: A multicenter, retrospective observational study was performed across 3 sites in Los Angeles County: an academic center (AC), a general pediatrics federally qualified health center (FQHC), and department of public health (DPH) tuberculosis clinics. Patients initiated on TBI treatment age 1 months to 17 years between 2018 and 2020 were included. RBRs were defined as regimens: 3 months of weekly rifapentine and isoniazid, 4 months of daily rifampin, and 3 months of daily isoniazid and rifampin. RESULTS: We included 424 patients: 51 from AC, 327 from DPH, and 46 from FQHC. RBR use nearly doubled during the study period (from 43% in 2018 to 82% in 2020; P < .001). FQHC had the shortest time to chest radiograph and treatment initiation; however, AC and DPH were 4 times as likely to prescribe an RBR compared to FQHC (95% CI, 2.1-7.8). AC and DPH had similar completion rates (74%) and were 2.6 times as likely to complete treatment compared to FQHC (95% CI, 1.4-4.9). CONCLUSIONS: The use of RBRs for pediatric TBI varies significantly by clinical setting but is improving over time. Strategies are needed to improve RBR uptake, standardize care, and increase treatment completion, particularly among general pediatricians.


Assuntos
Tuberculose Latente , Pediatria , Tuberculose , Humanos , Criança , Lactente , Rifampina/uso terapêutico , Isoniazida/uso terapêutico , Antituberculosos/uso terapêutico , Tuberculose/tratamento farmacológico , Quimioterapia Combinada
5.
Oncogene ; 42(9): 627-637, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36650218

RESUMO

Exploring the relationship between various neurotransmitters and breast cancer cell growth has revealed their likely centrality to improving breast cancer treatment. Neurotransmitters play a key role in breast cancer biology through their effects on the cell cycle, epithelial mesenchymal transition, angiogenesis, inflammation, the tumor microenvironment and other pathways. Neurotransmitters and their receptors are vital to the initiation, progression and drug resistance of cancer and progress in our biological understanding may point the way to lower-cost and lower-risk antitumor therapeutic strategies. This review discusses multiple neurotransmitters in the context of breast cancer. It also discusses risk factors, repurposing of pharmaceuticals impacting neurotransmitter pathways, and the opportunity for better integrated models that encompass exercise, the intestinal microbiome, and other non-pharmacologic considerations. Neurotransmitters' role in breast cancer should no longer be ignored; it may appear to complicate the molecular picture but the ubiquity of neurotransmitters and their wide-ranging impacts provide an organizing framework upon which further understanding and progress against breast cancer can be based.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/metabolismo , Neurotransmissores/metabolismo , Transição Epitelial-Mesenquimal , Microambiente Tumoral
6.
Oncogene ; 41(43): 4769-4778, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36182970

RESUMO

The brain-gut axis, a bidirectional network between the central and enteric nervous system, plays a critical role in modulating the gastrointestinal tract function and homeostasis. Recently, increasing evidence suggests that neuronal signaling molecules can promote gastrointestinal cancers, however, the mechanisms remain unclear. Aberrant expression of neurotransmitter signaling genes in colorectal cancer supports the role of neurotransmitters to stimulate tumor growth and metastatic spread by promoting cell proliferation, migration, invasion, and angiogenesis. In addition, neurotransmitters can interact with immune and endothelial cells in the tumor microenvironment to promote inflammation and tumor progression. As such, pharmacological targeting of neurotransmitter signaling represent a promising novel anticancer approach. Here, we present an overview of the current evidence supporting the role of neurotransmitters in colorectal cancer biology and treatment.


Assuntos
Neoplasias Colorretais , Neoplasias Gastrointestinais , Humanos , Células Endoteliais/metabolismo , Neurotransmissores , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Biologia , Microambiente Tumoral
9.
Oncotarget ; 7(33): 53668-53678, 2016 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-27449091

RESUMO

Most studies report on colon and rectal cancers collectively, even though biologic and prognostic differences exist between these disease entities. Here, we investigated the effects of sex, age, and ethnicity/race on rectal cancer (RC) mortality by stage focusing on differences before and after 2004.Using the SEER database, we identified 105,511 patients diagnosed with RC from 1988-2012. Main outcomes were disease-specific survival (DSS) and overall survival (OS).In patients with stage I-III RC, women achieved a longer DSS (HR 0.87, P < 0.001) than men, independent of age, from 1988-2012. In stage IV disease, the sex disparity favoring women was limited to the age 18-44 yr cohort (DSS HR 0.79, P < 0.001). The sex difference in DSS (Pinteraction = 0.009) was significantly reduced from 2004 to 2012 across all ages. Hispanics and Native Americans with locoregional RC had inferior DSS relative to Whites from 1988-2003, but these differences were not evident from 2004-2012 (Pinteraction = 0.001). Additionally, Asians with stage I-III RC had superior DSS from 2004 on compared to Whites. Mortality in African American patients improved modestly overall and remained significantly higher than other ethnicities/races across all stages.Sex disparities have narrowed in patients with metastatic RC, but persist in patients with stage I-III disease. These differences are most evident among young patients (18-44 years), where sex disparities have even widened in stage I-III disease. While outcomes have improved for Asians, Hispanics, and Native Americans with stage I-III rectal cancer, black-white disparities remain in all disease stages.


Assuntos
Neoplasias Retais/etnologia , Neoplasias Retais/mortalidade , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Programa de SEER , Caracteres Sexuais , Estados Unidos/epidemiologia , Adulto Jovem
10.
Clin Cancer Res ; 19(21): 5842-8, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23965904

RESUMO

Worldwide, colorectal cancer has a higher incidence rate in men than in women, suggesting a protective role for sex hormones in the development of the disease. Preclinical data support a role for estrogen and its receptors in the initiation and progression of colorectal cancer and establishes that protective effects of estrogen are exerted through ERß. Hormone replacement therapy (HRT) in postmenopausal women as well as consumption of soy reduces the incidence of colorectal cancer. In the Women's Health Initiative trial, use of HRT in postmenopausal women reduced the risk of colon cancer by 56% [95% confidence interval (CI), 0.38-0.81; P = 0.003]. A recent meta-analysis showed that in women, consumption of soy reduced the risk of colon cancer by 21% (95% CI, 0.03-0.35; P = 0.026). In this review, using the preclinical data, we translate the findings in the clinical trials and observational studies to define the role of estrogen in the prevention of colorectal cancer. We hypothesize that sometime during the tumorigenesis process ERß expression in colonocytes is lost and the estrogen ligand, HRT, or soy products, exerts its effects through preventing this loss. Thus, in the adenoma-to-carcinoma continuum, timing of HRT is a significant determinant of the observed benefit from this intervention. We further argue that the protective effects of estrogen are limited to certain molecular subtypes. Successful development of estrogen modulators for prevention of colorectal cancer depends on identification of susceptible colorectal cancer population(s). Thus, research to better understand the estrogen pathway is fundamental for clinical delivery of these agents.


Assuntos
Neoplasias Colorretais/metabolismo , Estrogênios/metabolismo , Transdução de Sinais , Animais , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Progesterona/metabolismo , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Pesquisa Translacional Biomédica
11.
J Phys Chem A ; 115(23): 6169-76, 2011 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-21341763

RESUMO

Methane hydrates with the three clathrate structures I, II, and H are studied by quantum-chemical methods. Hybrid density-functional theory B3LYP computations using periodic boundary conditions are combined with force-field methods for the thermal energy effects to calculate energetic, thermodynamic, and structural properties. The pressure dependencies for the crystal structures, lattice energies, and guest molecule interactions are derived. The quantum-chemical geometry optimizations predict too small cell volumes as compared to experimental data, but by including zero-point energy and thermal energy effects, we find the cell volumes increase and the correct densities are obtained. The phase transition from MH-I to ice Ih and methane was computed and found to occur at about 9.7 MPa.


Assuntos
Gelo , Metano/química , Modelos Químicos , Teoria Quântica , Temperatura , Água/química , Estrutura Molecular , Transição de Fase
12.
J Chem Phys ; 131(13): 134302, 2009 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-19814548

RESUMO

The size distribution of water clusters at equilibrium is studied using quantum-chemical calculations in combination with statistical thermodynamics. The necessary energetic data is obtained by quantum-chemical B3LYP computations and through extrapolations from the B3LYP results for the larger clusters. Clusters with up to 60 molecules are included in the equilibrium computations. Populations of different cluster sizes are calculated using both an ideal gas model with noninteracting clusters and a model where a correction for the interaction energy is included analogous to the van der Waals law. In standard vapor the majority of the water molecules are monomers. For the ideal gas model at 1 atm large clusters [56-mer (0-120 K) and 28-mer (100-260 K)] dominate at low temperatures and separate to smaller clusters [21-22-mer (170-280 K) and 4-6-mer (270-320 K) and to monomers (300-350 K)] when the temperature is increased. At lower pressure the transition from clusters to monomers lies at lower temperatures and fewer cluster sizes are formed. The computed size distribution exhibits enhanced peaks for the clusters consisting of 21 and 28 water molecules; these sizes are for protonated water clusters often referred to as magic numbers. If cluster-cluster interactions are included in the model the transition from clusters to monomers is sharper (i.e., occurs over a smaller temperature interval) than when the ideal-gas model is used. Clusters with 20-22 molecules dominate in the liquid region. When a large icelike cluster is included it will dominate for temperatures up to 325 K for the noninteracting clusters model. Thermodynamic properties (C(p), DeltaH) were calculated with in general good agreement with experimental values for the solid and gas phase. A formula for the number of H-bond topologies in a given cluster structure is derived. For the 20-mer it is shown that the number of topologies contributes to making the population of dodecahedron-shaped cluster larger than that of a lower-energy fused prism cluster at high temperatures.

13.
J Phys Chem A ; 110(50): 13388-93, 2006 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-17165863

RESUMO

The vibrational IR spectra in the O-H stretching region are computed for water clusters containing 6-22, 28, and 30 molecules using quantum-chemical calculations (B3LYP and an augmented basis set). For the cluster with 20 molecules, several different structures were studied. The vibrational spectrum was partitioned into contributions from different molecules according to their coordination properties. The frequency shifts depend on the number of donated/accepted H-bonds primarily of the two molecules participating in the H-bond, but also of the surrounding molecules H-bonding to these molecules. The frequencies of H-bonds between two molecules of the same coordination type are spread over a broad interval. The most downshifted hydrogen-bond vibrations are those donated by a single-donor 3-coordinated molecule where the H-bond is accepted by a single-acceptor molecule. The H-bonded neighbors influence the downshift, and their contribution can be rationalized in the same way as for the central dimer. Single donors/acceptors cause larger downshifts than 4-coordinated molecules, and the least downshift is obtained for double donors/acceptors. This result is at variance with the conception that experimental liquid water spectra may be divided into components for which larger downshifts imply higher H-bond coordination. A mean spectral contribution for each coordination type for the donor molecule was derived and fitted to the experimental liquid water IR spectrum, which enabled an estimation of the distribution of H-bond types and average number of H-bonds (3.0 +/- 0.2) in the liquid.

14.
Phys Chem Chem Phys ; 7(9): 1905-11, 2005 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-19787891

RESUMO

Quantum-chemical calculations of a variety of water clusters with eight, ten and twelve molecules were performed, as well as for selected clusters with up to 22 water molecules. Geometry optimizations were carried out at the B3LYP/cc-pVDZ level and single-point energies were calculated at the B3LYP/aug-cc-pVDZ level for selected clusters. The electronic energies were studied with respect to the geometry of the oxygen arrangement and six different characteristics of the hydrogen-bond arrangement in the cluster. Especially the effect of the placement of the non-hydrogen bonding hydrogens on the interaction energy was studied. Models for the interaction energy with respect to different characteristics of the hydrogen-bond arrangement were derived through least-square fits. The results from the study of the clusters with eight, ten and twelve molecules are used to predict possible low-energy structures for various shapes of clusters with up to 22 molecules.


Assuntos
Ligação de Hidrogênio , Água/química , Físico-Química/métodos , Simulação por Computador , Modelos Moleculares , Modelos Teóricos , Conformação Molecular , Software , Propriedades de Superfície , Termodinâmica
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