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1.
J Dairy Sci ; 107(4): 2444-2453, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37923207

RESUMO

In North America, surplus dairy calves are sold soon after birth and often marketed through a third party (e.g., live auction, livestock dealer) before entering veal or dairy beef production. Previous work has demonstrated that a percentage of calves have failed transfer of passive immunity (FTPI) and clinical signs of disease on arrival at calf-raising facilities, but little is known regarding calf condition during marketing. The objectives of this cross-sectional study were to (1) estimate the prevalence of FTPI and poor health outcomes in surplus calves on arrival at livestock dealers, and (2) investigate the association between calf-level variables (body weight, sex, source) and health outcomes. Two livestock dealers in Ohio were visited 2 to 3 times per week, with approximately 28 calves enrolled in the study per visit for a total of 1,119 calves. One blood sample per calf was obtained to evaluate FTPI by measuring serum total protein concentrations (using a cutoff <5.1 g/dL). Calves were clinically evaluated for signs of arthritis, broken ribs or tail, dehydration, depression, diarrhea, fever, navel inflammation, and respiratory disease by 2 observers; health outcomes were dichotomized using clinically relevant cut points. Descriptive statistics were used to estimate the prevalence of calves with poor health outcomes. Multivariable logistic regression models were built to investigate the effect of body weight, sex, and source on health outcomes. Nineteen percent (206/1,091) of calves had FTPI.


Assuntos
Doenças dos Bovinos , Animais , Bovinos , Estudos Transversais , Prevalência , Doenças dos Bovinos/epidemiologia , Peso Corporal , Marketing
2.
Molecules ; 27(4)2022 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-35209035

RESUMO

Three-dimensional cell culture has become a reliable method for reproducing in vitro cellular growth in more realistic physiological conditions. The surface hydrophobicity strongly influences the promotion of cell aggregate formation. In particular, for spheroid formation, highly water-repellent coatings seem to be required for the significant effects of the process. In this work, surfaces at different wettability have been compared to observe their influence on the growth and promotion of aggregates of representative mammalian cell lines, both tumoral and non-tumoral (3T3, HaCat and MCF-7 cell lines). The effect of increased hydrophobicity from TCPS to agarose hydrogel to mixed organic-inorganic superhydrophobic (SH) coating has been investigated by optical and fluorescence microscopy, and by 3D confocal profilometry, in a time scale of 24 h. The results show the role of less wettable substrates in inducing the formation of spheroid-like cell aggregates at a higher degree of sphericity for the studied cell lines.


Assuntos
Técnicas de Cultura de Células , Proliferação de Células , Hidrogéis/química , Esferoides Celulares/metabolismo , Células 3T3 , Animais , Humanos , Interações Hidrofóbicas e Hidrofílicas , Células MCF-7 , Camundongos , Esferoides Celulares/citologia
3.
Nature ; 522(7554): 98-101, 2015 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-26017307

RESUMO

Interactions between primary producers and bacteria impact the physiology of both partners, alter the chemistry of their environment, and shape ecosystem diversity. In marine ecosystems, these interactions are difficult to study partly because the major photosynthetic organisms are microscopic, unicellular phytoplankton. Coastal phytoplankton communities are dominated by diatoms, which generate approximately 40% of marine primary production and form the base of many marine food webs. Diatoms co-occur with specific bacterial taxa, but the mechanisms of potential interactions are mostly unknown. Here we tease apart a bacterial consortium associated with a globally distributed diatom and find that a Sulfitobacter species promotes diatom cell division via secretion of the hormone indole-3-acetic acid, synthesized by the bacterium using both diatom-secreted and endogenous tryptophan. Indole-3-acetic acid and tryptophan serve as signalling molecules that are part of a complex exchange of nutrients, including diatom-excreted organosulfur molecules and bacterial-excreted ammonia. The potential prevalence of this mode of signalling in the oceans is corroborated by metabolite and metatranscriptome analyses that show widespread indole-3-acetic acid production by Sulfitobacter-related bacteria, particularly in coastal environments. Our study expands on the emerging recognition that marine microbial communities are part of tightly connected networks by providing evidence that these interactions are mediated through production and exchange of infochemicals.


Assuntos
Diatomáceas/metabolismo , Diatomáceas/microbiologia , Ecossistema , Ácidos Indolacéticos/metabolismo , Fitoplâncton/metabolismo , Fitoplâncton/microbiologia , Rhodobacteraceae/metabolismo , Diatomáceas/citologia , Diatomáceas/genética , Metabolômica , Dados de Sequência Molecular , Oceanos e Mares , Fotossíntese , Fitoplâncton/citologia , Fitoplâncton/genética , Rhodobacteraceae/genética , Água do Mar/química , Transcriptoma , Triptofano/metabolismo
4.
J Investig Allergol Clin Immunol ; 30(6): 409-420, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32694101

RESUMO

Seafood is a major cause of food allergy and anaphylaxis worldwide. Shellfish is included among the "big eight" food groups, which are responsible for more than 90% of all cases of food allergy. Approximately 2.5% of the world's population has experienced an adverse reaction to seafood. Seafood allergy is one of the most frequent and lethal allergies that exist. The several allergenic proteins involved in allergic reactions that have been described in recent years include tropomyosin, arginine kinase, myosin light chain, and sarcoplasmic calcium-binding protein. Despite all the data reported in the last few years, shellfish allergy is still diagnosed and treated as it was 50 years ago. The only effective treatment to prevent allergic reactions to shellfish is avoidance. This review aims to update recently published data on shellfish allergy and to highlight those areas that have yet to be resolved.


Assuntos
Hipersensibilidade a Frutos do Mar/diagnóstico , Hipersensibilidade a Frutos do Mar/terapia , Algoritmos , Alérgenos/imunologia , Animais , Tomada de Decisão Clínica , Reações Cruzadas/imunologia , Gerenciamento Clínico , Suscetibilidade a Doenças , Epitopos/imunologia , Humanos , Imunoglobulina E/imunologia , Fatores de Risco , Frutos do Mar/efeitos adversos , Hipersensibilidade a Frutos do Mar/etiologia , Avaliação de Sintomas
5.
Health Educ Res ; 35(1): 44-59, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31965169

RESUMO

Smoking education and prevention campaigns have had marked success in reducing rates of tobacco use among adolescents, however, disparities in use continue to exist. It is critical to assess if adolescents at risk for tobacco use are being exposed to antitobacco campaigns. We used data from Wave 2 of the Population Assessment of Tobacco and Health Study to assess the relationship between exposure to three antitobacco campaigns and key characteristics related to higher risk of cigarette use using full-sample weights and Poisson regression models with robust variance. Adjusted models identified that exposure to antitobacco campaigns was more common among racial and sexual minority adolescents and adolescents who: reported exposure to tobacco marketing, spent more time using media and had household income greater than $25 000. While some high-risk youth are more likely to report exposure to campaigns, there are some priority groups that are not being reached by current efforts compared with non-priority groups, including youth living in households with income below the poverty line and adolescents who are susceptible to cigarette smoking. Future campaigns should consider targeting these groups specifically in order to reduce tobacco use disparities.


Assuntos
Comunicação em Saúde , Prevenção do Hábito de Fumar/organização & administração , Fumar Tabaco/prevenção & controle , Adolescente , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Marketing , Grupos Raciais/estatística & dados numéricos , Minorias Sexuais e de Gênero/estatística & dados numéricos , Fatores Socioeconômicos
6.
Surgeon ; 18(5): e1-e6, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31718929

RESUMO

BACKGROUND: Changes to working practices and increasing service demand have contributed to low morale amongst UK surgical trainees, with pressures particularly acute 'out of hours' (OOH). Surgeons may be expected to be 'on call' for multiple hospitals, or to provide remote consultations, yet healthcare systems may undermine their professional safety and patient care. This cross-sectional study sought to define the perceptions of UK-based Royal College of Surgeons of Edinburgh (RCSEd) affiliated trainees of OOH surgical care and training. METHODS: The RCSEd Trainees' Committee conducted a design-thinking exercise to produce an online questionnaire. Non-consultant grade RCSEd Members and Fellows were invited to participate. Quantitative data was analysed using descriptive statistics, and qualitative data was coded to identify emergent themes. RESULTS: One hundred and fifty-five surgeons participated. Of those surgeons working in multiple hospitals OOH (n = 16), many did not receive access cards (12[75%]) or site-specific induction (13[81%]), and 8(50%) were not confident in using local electronic investigation and records systems. Only 14/114 (12%) of the surgeons providing remote opinion had access to a consultation record system, and most perceived dissatisfaction with the system. Emergent themes from qualitative data revealed that trainee surgeons desire specific training in OOH working, concerns that OOH work experience is diminishing, and that hospital infrastructure such as IT and communications, rest facilities and catering were inadequate in facilitating safe care. CONCLUSIONS: The participants perceived that the systems supporting delivery of safe surgical care OOH were inadequate. Hospital leaders should ensure that systems minimise risk to staff and patients.


Assuntos
Plantão Médico/organização & administração , Educação de Pós-Graduação em Medicina/organização & administração , Cirurgia Geral/educação , Admissão e Escalonamento de Pessoal/organização & administração , Medicina Estatal , Competência Clínica , Estudos Transversais , Humanos , Inquéritos e Questionários , Reino Unido , Carga de Trabalho
7.
Int J Mol Sci ; 21(23)2020 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-33255401

RESUMO

The surface activity, aggregates morphology, size and charge characteristics of binary catanionic mixtures containing a cationic amino acid-derived surfactant N(π), N(τ)-bis(methyl)-L-Histidine tetradecyl amide (DMHNHC14) and an anionic surfactant (the lysine-based surfactant Nα-lauroyl-Nεacetyl lysine (C12C3L) or sodium myristate) were investigated for the first time. The cationic surfactant has an acid proton which shows a strong pKa shift irrespective of aggregation. The resulting catanionic mixtures exhibited high surface activity and low critical aggregation concentration as compared with the pure constituents. Catanionic vesicles based on DMHNHC14/sodium myristate showed a monodisperse population of medium-size aggregates and good storage stability. According to Small-Angle X-Ray Scattering (SAXS), the characteristics of the bilayers did not depend strongly on the system composition for the positively charged vesicles. Negatively charged vesicles (cationic surfactant:myristate ratio below 1:2) had similar bilayer composition but tended to aggregate. The DMHNHC14-rich vesicles exhibited good antibacterial activity against Gram-positive bacteria and their bactericidal effectivity declined with the decrease of the cationic surfactant content in the mixtures. The hemolytic activity and cytotoxicity of these catanionic formulations against non-tumoral (3T3, HaCaT) and tumoral (HeLa, A431) cell lines also improved by increasing the ratio of cationic surfactant in the mixture. These results indicate that the biological activity of these systems is mainly governed by the cationic charge density, which can be modulated by changing the cationic/anionic surfactant ratio in the mixtures. Remarkably, the incorporation of cholesterol in those catanionic vesicles reduces their cytotoxicity and increases the safety of future biomedical applications of these systems.


Assuntos
Aminoácidos/química , Cátions/química , Agregados Proteicos , Tensoativos/química , Aminoácidos/farmacologia , Ânions/química , Antibacterianos/química , Antibacterianos/farmacologia , Cátions/farmacologia , Bactérias Gram-Positivas/efeitos dos fármacos , Ácido Mirístico/química , Espalhamento a Baixo Ângulo , Tensoativos/farmacologia , Difração de Raios X
8.
Nature ; 494(7437): 349-52, 2013 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-23334410

RESUMO

Climate change is predicted to increase both drought frequency and duration, and when coupled with substantial warming, will establish a new hydroclimatological model for many regions. Large-scale, warm droughts have recently occurred in North America, Africa, Europe, Amazonia and Australia, resulting in major effects on terrestrial ecosystems, carbon balance and food security. Here we compare the functional response of above-ground net primary production to contrasting hydroclimatic periods in the late twentieth century (1975-1998), and drier, warmer conditions in the early twenty-first century (2000-2009) in the Northern and Southern Hemispheres. We find a common ecosystem water-use efficiency (WUE(e): above-ground net primary production/evapotranspiration) across biomes ranging from grassland to forest that indicates an intrinsic system sensitivity to water availability across rainfall regimes, regardless of hydroclimatic conditions. We found higher WUE(e) in drier years that increased significantly with drought to a maximum WUE(e) across all biomes; and a minimum native state in wetter years that was common across hydroclimatic periods. This indicates biome-scale resilience to the interannual variability associated with the early twenty-first century drought--that is, the capacity to tolerate low, annual precipitation and to respond to subsequent periods of favourable water balance. These findings provide a conceptual model of ecosystem properties at the decadal scale applicable to the widespread altered hydroclimatic conditions that are predicted for later this century. Understanding the hydroclimatic threshold that will break down ecosystem resilience and alter maximum WUE(e) may allow us to predict land-surface consequences as large regions become more arid, starting with water-limited, low-productivity grasslands.


Assuntos
Mudança Climática/estatística & dados numéricos , Secas/estatística & dados numéricos , Ecossistema , Plantas/metabolismo , Água/metabolismo , Mudança Climática/história , Secas/história , História do Século XX , História do Século XXI , Poaceae/metabolismo , Chuva , Árvores/metabolismo , Ciclo Hidrológico
11.
Psychol Res ; 82(2): 255-271, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27778123

RESUMO

We hypothesize that a shared spatial attention mechanism is used for both perception and action. To this end we created a new dual-task version of the classical Simon task. In one task, the spatial-input task, associated with input spatial attention, participants named one shape out of two bilaterally presented colored shapes. In a second task, the spatial-output task, associated with output spatial attention, participants discriminated between high and low pitch tones by pressing either a left or a right key. In Experiment 1, input for both tasks appeared simultaneously, and participants were instructed not to prioritize either task. A between tasks Simon-like effect was found for responses to both tasks. Reaction times were shorter when the side of the relevant shape in the spatial-input task and the side of the correct response in the spatial-output task were congruent. In Experiment 2, we manipulated the stimulus-onset asynchrony (SOA) between the inputs for the two tasks and showed that the Simon-like effect remained intact at all SOAs. Experiment 3 was similar to Experiment 1 except that the vocal response for the spatial-input task was not speeded. A Simon-like effect was still observed. Experiment 4 was the same as Experiment 3 except that the non-speeded response for the spatial-input task was manual rather than vocal. No Simon-like effect was observed in this experiment. Our results support a shared spatial attention mechanism involved in the Simon effect and indicate that this spatial attention mechanism is shared by perception and action.


Assuntos
Atenção/fisiologia , Reconhecimento Visual de Modelos , Desempenho Psicomotor/fisiologia , Percepção Espacial , Percepção Visual , Adulto , Feminino , Humanos , Masculino , Estimulação Luminosa , Tempo de Reação/fisiologia , Adulto Jovem
13.
Acta Paediatr ; 106(6): 979-983, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28218949

RESUMO

AIM: Although recognising insulin resistance (IR) in children is particularly important, the gold standard test used to diagnose it, the euglyceamic glucose clamp, is costly, invasive and is not routinely available in our clinical settings in Mexico. This study evaluated whether the triglyceride-glucose (TyG) index would provide a useful alternative. METHODS: A total of 2779 school children aged seven to 17 years, from Durango, Mexico, were enrolled during 2015-2016. The gold standard euglyceamic-hyperinsulinemic clamp test was performed in a randomly selected subsample of 125 children, and diagnostic concordance between the TyG index and the homoeostasis model assessment of IR was evaluated in all of the 2779 enrolled children. RESULTS: The best cut-off values for recognising IR using the TyG index were 4.65 for prepubertal girls and boys, 4.75 for pubertal girls and 4.70 for pubertal boys. Concordance between the TyG index and the homoeostasis model assessment of IR was 0.910 and 0.902 for the prepubertal girls and boys, 0.932 for the pubertal girls and 0.925 for the pubertal boys. CONCLUSION: The TyG index was useful for recognising IR in both prepubertal and pubertal children and could provide a feasible alternative to the costly and invasive gold standard test for IR in resource-limited settings.


Assuntos
Glicemia , Resistência à Insulina , Triglicerídeos/sangue , Adolescente , Biomarcadores/sangue , Criança , Feminino , Humanos , Hiperinsulinismo/sangue , Hiperinsulinismo/diagnóstico , Masculino
14.
Proc Natl Acad Sci U S A ; 111(14): E1327-33, 2014 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-24706867

RESUMO

Photosynthesis is the process by which plants harvest sunlight to produce sugars from carbon dioxide and water. It is the primary source of energy for all life on Earth; hence it is important to understand how this process responds to climate change and human impact. However, model-based estimates of gross primary production (GPP, output from photosynthesis) are highly uncertain, in particular over heavily managed agricultural areas. Recent advances in spectroscopy enable the space-based monitoring of sun-induced chlorophyll fluorescence (SIF) from terrestrial plants. Here we demonstrate that spaceborne SIF retrievals provide a direct measure of the GPP of cropland and grassland ecosystems. Such a strong link with crop photosynthesis is not evident for traditional remotely sensed vegetation indices, nor for more complex carbon cycle models. We use SIF observations to provide a global perspective on agricultural productivity. Our SIF-based crop GPP estimates are 50-75% higher than results from state-of-the-art carbon cycle models over, for example, the US Corn Belt and the Indo-Gangetic Plain, implying that current models severely underestimate the role of management. Our results indicate that SIF data can help us improve our global models for more accurate projections of agricultural productivity and climate impact on crop yields. Extension of our approach to other ecosystems, along with increased observational capabilities for SIF in the near future, holds the prospect of reducing uncertainties in the modeling of the current and future carbon cycle.


Assuntos
Clorofila/fisiologia , Produtos Agrícolas/fisiologia , Fotossíntese , Fluorescência , Modelos Teóricos
15.
J Exp Bot ; 67(1): 275-86, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26482242

RESUMO

Most studies assessing chlorophyll fluorescence (ChlF) have examined leaf responses to environmental stress conditions using active techniques. Alternatively, passive techniques are able to measure ChlF at both leaf and canopy scales. However, the measurement principles of both techniques are different, and only a few datasets concerning the relationships between them are reported in the literature. In this study, we investigated the potential for interchanging ChlF measurements using active techniques with passive measurements at different temporal and spatial scales. The ultimate objective was to determine the limits within which active and passive techniques are comparable. The results presented in this study showed that active and passive measurements were highly correlated over the growing season across nitrogen treatments at both canopy and leaf-average scale. At the single-leaf scale, the seasonal relation between techniques was weaker, but still significant. The variability within single-leaf measurements was largely related to leaf heterogeneity associated with variations in CO2 assimilation and stomatal conductance, and less so to variations in leaf chlorophyll content, leaf size or measurement inputs (e.g. light reflected and emitted by the leaf and illumination conditions and leaf spectrum). This uncertainty was exacerbated when single-leaf analysis was limited to a particular day rather than the entire season. We concluded that daily measurements of active and passive ChlF at the single-leaf scale are not comparable. However, canopy and leaf-average active measurements can be used to better understand the daily and seasonal behaviour of passive ChlF measurements. In turn, this can be used to better estimate plant photosynthetic capacity and therefore to provide improved information for crop management.


Assuntos
Clorofila/química , Fluorescência , Nitrogênio/metabolismo , Triticum/química , Folhas de Planta/química
16.
Genet Mol Res ; 14(2): 6094-100, 2015 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-26125810

RESUMO

We investigated the expression of Brother of Regulator of Imprinted Sites (BORIS) and CCCTC-binding factor (CTCF) in squamous intraepithelial lesions and cervical cancer. To analyze BORIS and CTCF expression, an endocervical cytobrush sample was taken for total RNA isolation. CTCF and BORIS mRNA was quantified from total RNA using quantitative reverse transcription-polymerase chain reaction. A total of 71 samples were collected and classified according to the Bethesda Classification of squamous intraepithelial lesions. BORIS expression was observed in 9 (12.7%) samples; of these, 5.3, 5.9, 14.8, and 37.5% in the groups that were cytology negative for intraepithelial lesion or malignancy, low-grade squamous intraepithelial lesions (LSIL), high-grade squamous intraepithelial lesions (HSIL), and invasive cervical carcinoma, respectively. The expression level of BORIS was significantly higher in the group with invasive cervical carcinoma as compared with the groups negative for intraepithelial lesion or malignancy, LSIL, and HSIL (P < 0.0005). CTCF mRNA was expressed in all samples. CTCF expression was significantly higher in carcinoma groups compared with LSIL, HSIL, and negative for intraepithelial lesion or malignancy groups. We found that BORIS and CTCF expressions in the LSIL and invasive cervical carcinoma groups were higher than expression in cytological normal samples. Additional studies should be conducted to examine the function of transcription factors during different stages of the transformation of cervical cancer cells.


Assuntos
Proteínas de Ligação a DNA/genética , Proteínas Repressoras/genética , Lesões Intraepiteliais Escamosas Cervicais/genética , Lesões Intraepiteliais Escamosas Cervicais/patologia , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia , Adolescente , Adulto , Biomarcadores Tumorais/genética , Fator de Ligação a CCCTC , Estudos Transversais , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Prognóstico , Adulto Jovem
17.
Knee Surg Sports Traumatol Arthrosc ; 23(5): 1330-6, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-24482215

RESUMO

PURPOSE: To report the functional outcome, implant survival, and patient mortality after mega prosthetic distal femoral arthroplasty according to the surgical indication. METHODS: A prospective database was compiled for 45 consecutive patients undergoing distal femoral arthroplasty, of which 26 had fractures of the distal femur (group 1) and 19 underwent revision of a total knee arthroplasty (group 2). There were 17 males and 28 females with a median age of 74.5 years. Short form (SF)-12 scores were recorded pre-operatively (before the fracture or revision) and 1 year post-operatively, at which point a Toronto Extremity Salvage Score (TESS) was also obtained. Length of hospital stay and return to place of domicile was obtained from the hospital database. Mortality status was obtained from the General Register Office for Scotland. No patient was lost to follow-up. RESULTS: The 1-year physical (52.4) and mental (63.4) components of the SF-12 score and the TESS (70.5 %) did not significantly differ between the groups (n.s.). The fracture group, however, had a longer length of stay (8 vs. 19 days, p = 0.001) and were also less likely to return to their original domicile (odds ratio 9.5, p = 0.02). The overall implant survival rate was 85 % at 5 years, which was worse for the fracture group (80 vs. 90 %, n.s.). The 5-year mortality rate for the revision group was 17 %, whereas the fracture group demonstrated a greater mortality rate of 43 % (n.s.). CONCLUSION: The functional outcome, revision rate, and mortality of patients undergoing distal femoral arthroplasty for non-tumour reasons are not influenced by indication, but patients undergoing surgery for fractures of the distal femur have a longer length of stay and are less likely to return home. Distal femoral arthroplasty should be considered as a management option for non-tumour salvage procedures of the distal femur. LEVEL OF EVIDENCE: Retrospective comparative study, Level III.


Assuntos
Artroplastia do Joelho/métodos , Fraturas do Fêmur/cirurgia , Articulação do Joelho/fisiopatologia , Amplitude de Movimento Articular/fisiologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Fraturas do Fêmur/mortalidade , Fraturas do Fêmur/fisiopatologia , Humanos , Articulação do Joelho/cirurgia , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Estudos Prospectivos , Estudos Retrospectivos , Escócia/epidemiologia , Taxa de Sobrevida/tendências
18.
Tissue Antigens ; 83(4): 247-59, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24517517

RESUMO

The so-called tumor necrosis factor (TNF) block includes the TNFA, lymphotoxin alpha and beta (LTA and LTB) genes with single-nucleotide polymorphisms (SNP) and microsatellites with an allele frequency that exhibits interpopulation variability. To date, no reports have included both SNPs and microsatellites at the TNF block to study Mestizo or Amerindian populations from Mexico. In this study, samples of five Mexican Mestizo populations (Durango, Guadalajara, Monterrey, Puebla, and Tierra Blanca) and four native-Mexican populations (North Lacandonians, South Lacandonians, Tepehuanos, and Yaquis) were genotyped for two SNPs (LTA+252A>G and TNFA-308G>A) and four microsatellites (TNFa, d, e, and f), to analyze the genetic substructure of the Mexican population. Allele and haplotype frequencies, linkage disequilibrium (LD), and interpopulation genetic relationships were calculated. There was significant LD along almost all of the TNF block but the lowest D' values were observed for the TNFf-TNFd pair. Mestizos showed higher allele and haplotype diversity than did natives. The genetic differentiation level was reduced among Mestizos; however, a slightly, but significant genetic substructure was observed between northern and southern Mexican Mestizos. Among the Amerindian populations, the genetic differentiation level was significantly elevated, particularly in both North and South Lacandonians. Furthermore, among Southern Lacandonians, inhabitants of Lacanja town were the most differentiated from all the Mexicans analyzed. The data presented here will serve as a reference for further population and epidemiological studies including these TNF polymorphisms in the Mexican population.


Assuntos
Haplótipos , Indígenas Norte-Americanos/genética , Desequilíbrio de Ligação , Repetições de Microssatélites , Polimorfismo de Nucleotídeo Único , Fator de Necrose Tumoral alfa/genética , Feminino , Humanos , Masculino , México
19.
Ann Surg Oncol ; 21(6): 1963-8, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24562930

RESUMO

PURPOSE: Basal subtype, as approximated by the triple-negative phenotype (ER-PR-Her2-), has correlated with higher LRR in recent studies. Indications for postmastectomy RT (PMRT) in women with 0-3 positive lymph nodes remain unclear. We evaluated the importance of biologic subtype in a cohort of women with LRR after mastectomy. METHODS: We identified 22 women with 0-3 positive lymph nodes at our institution who were initially treated with mastectomy (without post-mastectomy radiation), suffered LRRs, and had paraffin-embedded tissue blocks from the primary mastectomy specimen available for staining. None of these women received PMRT. We case-control matched these to 29 women with 0-3 positive nodes who had mastectomy (no PMRT) and remained without evidence of disease at last follow-up and had available primary specimens for processing. We matched controls for age (±3 years) and follow-up duration (<5 year vs. more). Paraffin-embedded specimens were used to construct a triple-redundant tissue microarray. We used conditional logistic regressions to study the association between each predictor and LRR. Results were summarized based on odds ratio (OR). RESULTS: On univariate analysis, ER+, PR+, or the combination was strongly associated with lower odds of LRR. Basal subtype, as approximated by ER-PR-Her2- (TN), was associated with higher LRR (OR 8.5, p = 0.048). Use of chemotherapy also was associated with lower LRR (OR 0.126, p = 0.0073). CONCLUSIONS: Our data are concordant with reports from others demonstrating that TN phenotype is associated with higher LRR and can be considered along with other predictors of LRR when selecting women for PMRT.


Assuntos
Biomarcadores Tumorais/análise , Recidiva Local de Neoplasia/química , Recidiva Local de Neoplasia/patologia , Neoplasias de Mama Triplo Negativas/química , Neoplasias de Mama Triplo Negativas/patologia , Antineoplásicos/uso terapêutico , Estudos de Casos e Controles , Feminino , Humanos , Metástase Linfática , Mastectomia , Fenótipo , Receptor ErbB-2/análise , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Estudos Retrospectivos , Neoplasias de Mama Triplo Negativas/terapia
20.
Ecology ; 95(8): 2121-33, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25230464

RESUMO

Grasslands across the United States play a key role in regional livelihood and national food security. Yet, it is still unclear how this important resource will respond to the prolonged warm droughts and more intense rainfall events predicted with climate change. The early 21st-century drought in the southwestern United States resulted in hydroclimatic conditions that are similar to those expected with future climate change. We investigated the impact of the early 21st-century drought on aboveground net primary production (ANPP) of six desert and plains grasslands dominated by C4 (warm season) grasses in terms of significant deviations between observed and expected ANPP. In desert grasslands, drought-induced grass mortality led to shifts in the functional response to annual total precipitation (P(T)), and in some cases, new species assemblages occurred that included invasive species. In contrast, the ANPP in plains grasslands exhibited a strong linear function of the current-year P(T) and the previous-year ANPP, despite prolonged warm drought. We used these results to disentangle the impacts of interannual total precipitation, intra-annual precipitation patterns, and grassland abundance on ANPP, and thus generalize the functional response of C4 grasslands to predicted climate change. This will allow managers to plan for predictable shifts in resources associated with climate change related to fire risk, loss of forage, and ecosystem services.


Assuntos
Secas/história , Ecossistema , História do Século XXI , Espécies Introduzidas , Chuva , Estações do Ano , Fatores de Tempo , Estados Unidos
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