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1.
bioRxiv ; 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38712234

RESUMO

The sub-ventricular zone (SVZ) is the most well-characterized neurogenic area in the mammalian brain. We previously showed that in 65% of patients with glioblastoma (GBM), the SVZ is a reservoir of cancer stem-like cells that contribute to treatment resistance and emergence of recurrence. Here, we built a single-nucleus RNA-sequencing-based microenvironment landscape of the tumor mass (T_Mass) and the SVZ (T_SVZ) of 15 GBM patients and 2 histologically normal SVZ (N_SVZ) samples as controls. We identified a mesenchymal signature in the T_SVZ of GBM patients: tumor cells from the T_SVZ relied on the ZEB1 regulatory network, whereas tumor cells in the T_Mass relied on the TEAD1 regulatory network. Moreover, the T_SVZ microenvironment was predominantly characterized by tumor-supportive microglia, which spatially co-exist and establish heterotypic interactions with tumor cells. Lastly, differential gene expression analyses, predictions of ligand-receptor and incoming/outgoing interactions, and functional assays revealed that the IL-1ß/IL-1RAcP and Wnt-5a/Frizzled-3 pathways are therapeutic targets in the T_SVZ microenvironment. Our data provide insights into the biology of the SVZ in GBM patients and identify specific targets of this microenvironment.

2.
Chemosphere ; 183: 454-470, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28564625

RESUMO

Water and Suspended Particulate Material (SPM) samples analysed in this work were collected in the austral summer 2011/12 from six shallow Antarctic lakes (Carezza, Edmonson Point 14 and 15a, Gondwana, Inexpressible Island 10b and Tarn Flat 20) of Terra Nova Bay (Northern Victoria Land, Antarctica). The total concentrations of a large suite of inorganic analytes were determined, in order to gain insight into the natural processes regulating species distribution, define natural background values and detect possible present or future local and/or global anthropogenic contamination. Lake water composition was found to be influenced by marine spray, lake geographical position and meltwater input. Seasonal variability was also evaluated for each analyte, and explained considering the natural transport processes involving each species. Multivariate chemometric techniques were used in order to identify groups of samples with similar characteristics and find out similarities and correlations among variables. The variability observed within the water samples is closely connected to the marine aerosol input; hence, it is primarily a consequence of geographical and meteorological factors, such as distance from the ocean and period of year. Higher element concentrations have been found in SPM than in water, suggesting that weathering plays an important role on the chemistry of these lakes or that adsorption processes take place. SPM samples were also examined with a Scanning Electron Microscope (SEM), and many diatoms belonging to different species were detected. No clear evidence of a relevant metal contamination was found in the investigated area.


Assuntos
Baías/química , Compostos Inorgânicos/análise , Lagos/química , Água/química , Aerossóis/análise , Regiões Antárticas , Diatomáceas , Geografia , Metais/análise , Material Particulado/análise , Estações do Ano
3.
Phys Chem Chem Phys ; 18(18): 13118-25, 2016 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-27113137

RESUMO

The stability of sodium complexes with poly-carboxylic and polyamino-carboxylic acids is investigated with ion-selective electrode-Na(+) potentiometry, working at strictly constant ionic strength. It is observed that the formation constants of the Na(+) complexes with monoligand stoichiometry (ML) increase with the number of charges on the ligand. For example, in poly-carboxylic acids this dependency is linear and is well captured by an experimental equation. A different behaviour is observed for the poly-amino carboxylic acids, which show higher complexation capabilities reaching a plateau of the binding energy past a specific ligand size. The experimental results are discussed qualitatively using ab initio calculations based on DFT B3LYP, and the principal electronic characteristics of the ligands under investigation are identified. As a result of the flexibility imparted by the long chains of polyamino-carboxylic ligands, both experimental and theoretical models demonstrate that nitrogen atoms in proximity of Na(+) ions can participate in the metal coordination, thus providing further stabilization for the complexes. Moreover, by increasing the ligand size the stabilization gained in terms of ΔG reached a plateau for EDTA, in agreement with experimental observations.

4.
Heredity (Edinb) ; 113(4): 277-86, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24690754

RESUMO

The evolution of the mitochondrial genome and its potential adaptive impact still generates vital debates. Even if mitochondria have a crucial functional role, as they are the main cellular energy suppliers, mitochondrial DNA (mtDNA) introgression is common in nature, introducing variation in populations upon which selection may act. Here we evaluated whether the evolution of mtDNA in a rodent species affected by mtDNA introgression is explained by neutral expectations alone. Variation in one mitochondrial and six nuclear markers in Myodes glareolus voles was examined, including populations that show mtDNA introgression from its close relative, Myodes rutilus. In addition, we modelled protein structures of the mtDNA marker (cytochrome b) and estimated the environmental envelopes of mitotypes. We found that massive mtDNA introgression occurred without any trace of introgression in the analysed nuclear genes. The results show that the native glareolus mtDNA evolved under past positive selection, suggesting that mtDNA in this system has selective relevance. The environmental models indicate that the rutilus mitotype inhabits colder and drier habitats than the glareolus one that can result from local adaptation or from the geographic context of introgression. Finally, homology models of the cytochrome b protein revealed a substitution in rutilus mtDNA in the vicinity of the catalytic fraction, suggesting that differences between mitotypes may result in functional changes. These results suggest that the evolution of mtDNA in Myodes may have functional, ecological and adaptive significance. This work opens perspective onto future experimental tests of the role of natural selection in mtDNA introgression in this system.


Assuntos
Arvicolinae/genética , Ecossistema , Evolução Molecular , Mitocôndrias/genética , Adaptação Fisiológica , Animais , Arvicolinae/classificação , Arvicolinae/fisiologia , Citocromos b/genética , DNA Mitocondrial/genética , Variação Genética , Masculino , Dados de Sequência Molecular , Filogenia , Seleção Genética
5.
Arq Gastroenterol ; 38(4): 272-5, 2001.
Artigo em Português | MEDLINE | ID: mdl-12068539

RESUMO

BACKGROUND: The stomach through its mechanical and chemical processes has an unique role in the food processing and bioavailability. Hence gastrectomy has predictable and modifiable nutritional consequences depending upon its knowledge and the post-surgery therapies. OBJECTIVE: To point out the impact of gastrectomy on the nutritional status focusing on both mechanical and chemical actions of stomach on intaked foods. RESULTS: The protein-energy malnutrition and consequent body-weight loss follow reversely the remainer gastric volume and post-operatory length and have anorexy and intestinal malabsorption as their main causes. Lower food intake is probably due to either emotional factors or chemical mediators acting centrally on hypothalamus. The diarrhea may be due to either increased peristalsis or bacterial overgrowth both aggravated by exocrine-pancreas deficiency and gallbladder overflow. The intestinal malabsorption leading to fecal losses of fat and or nitrogen as well as lower utilization of dietary calcium and liposoluble vitamins. The gastrectomy-related anemia is consequent to lower secretion of both HCl and intrinsic factor leading to a decreased solubilization of iron and lower absorption of vitamin B12, respectively. CONCLUSION: Body-weight loss and anemia are the protein-energy malnutrition findings often found in these patients whose severity and lasting depend upon the type of surgery, post-surgery length and received nutritional care, being strongly recommended a supervisioned dietary care.


Assuntos
Gastrectomia/efeitos adversos , Desnutrição Proteico-Calórica/etiologia , Anemia/etiologia , Anorexia/etiologia , Síndrome de Esvaziamento Rápido/etiologia , Humanos , Redução de Peso
6.
Arq Gastroenterol ; 34(3): 139-47, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9611291

RESUMO

Transthyretin and retinol-binding protein are sensitive markers of acute protein-calorie malnutrition both for early diagnosis and dietary evaluation. A preliminary study showed that retinol-binding protein is the most sensitive marker of protein-calorie malnutrition in cirrhotic patients, even those with the mild form of the disease (Child A). However, in addition to being affected by protein-calorie malnutrition, the levels of these short half-life-liver-produced proteins are also influenced by other factors of a nutritional (zinc, tryptophan, vitamin A, etc) and non-nutritional (sex, aging, hormones, renal and liver functions and inflammatory activity) nature. These interactions were investigated in 11 adult male patients (49.9 +/- 9.2 years of age) with alcoholic cirrhosis (Child-Pugh grade A) and with normal renal function. Both transthyretin and retinol binding protein were reduced below normal levels in 55% of the patients, in close agreement with their plasma levels of retinol. In 67% of the patients (4/6), the reduced levels of transthyretin and retinol-binding protein were caused by altered liver function and in 50% (3/6) they were caused by protein-calorie malnutrition. Thus, the present data, taken as a whole, indicate that reduced transthyretin and retinol-binding protein levels in mild cirrhosis of the liver are mainly due to liver failure and/or vitamin A status rather than representing an isolated protein-calorie malnutrition indicator.


Assuntos
Aminoácidos/sangue , Cirrose Hepática Alcoólica/metabolismo , Pré-Albumina/análise , Desnutrição Proteico-Calórica/sangue , Proteínas de Ligação ao Retinol/análise , Hormônios Tireóideos/sangue , Vitamina A/sangue , Zinco/sangue , Adulto , Humanos , Falência Hepática , Masculino , Pessoa de Meia-Idade , Proteínas Plasmáticas de Ligação ao Retinol
7.
Arq Gastroenterol ; 34(1): 13-21, 1997.
Artigo em Português | MEDLINE | ID: mdl-9458955

RESUMO

The effects of the clinical and dietetics in patient managements on the protein-energy status of hospitalized patients were retrospectively (four yr) investigated in 243 adult (49 +/- 16 yr), male (168) and female (75) patients suffering from chronic liver diseases (42%), intestinal diseases with diarrhea (14%), digestive cancers (11%), chronic pancreatitis (10%), stomach and duodenum diseases (7%), acute pancreatitis (7%), primary protein-energy malnutrition (3%), esophagus diseases (3%), intestinal diseases with constipation 14 (2%) and chronic alcoholism (2%). The protein-energy nutritional status assessed by combinations of anthropometric and blood parameters showed 75% of protein energy malnutrition at the hospital entry mostly (4/5) in severe and moderate grades. The overall average of hospitalization was 20 +/- 15 days being the shortest (13 +/- 5,7 days) for esophagus diseases and the longest (28 +/- 21 days) for the intestinal diseases with diarrhea patients which also received mostly (42%) of the enteral and/or parenteral feedings followed by acute pacreatitis (41%) and digestive cancers (31%) patients. When compared to the entry the protein-energy malnutrition rate at the discharge decreased only 5% despite the increasing of 30% found on the protein-energy intake. The main improvement of the protein-energy nutritional status were attained to those patients showing protein-energy malnutrition milder degrees at the entry which belonged mostly to primary protein-energy malnutrition, acute pancreatitis and intestinal diseases with diarrhea diseases. The later two groups showed protein-energy nutritional status improvement only after the second week of hospitalization. The digestive cancers patients had their protein-energy nutritional status worsened throughout the hospitalization whereas it happened only in the first week for the intestinal diseases with diarrhea and chronic liver diseases patients, improving thereafter up to the discharge. The protein-energy nutritional status improvement found in few patients could be attributed to some complementary factors such as theirs mild degree of protein-energy malnutrition at entry and/or non-invasive propedeutics and/or enteral-parenteral feddings and/or longer hospitalization staying. The institutional causes for the unexpected lack of nutritional responses by the patients were probably the high demand for the few available beds which favour the hospitalization of the most severed patients and the university-teaching pressure for the high rotation of the available beds. Both often resulting in early discharging. In persisting the current physical area and attendance demand one could suggest an aggressive support early at the entry preceding and/or accompanying the more invasive propedeutical procedures.


Assuntos
Gastroenteropatias , Hospitalização , Pacientes Internados , Estado Nutricional , Desnutrição Proteico-Calórica , Adulto , Ingestão de Energia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação Nutricional , Apoio Nutricional , Prevalência , Desnutrição Proteico-Calórica/epidemiologia , Estudos Retrospectivos
8.
Nutrition ; 12(7-8): 519-23, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8878146

RESUMO

In five male cirrhotic patients (Child A) and in four age- and sex-matched healthy control subjects, whole-body protein turnover was measured using a single oral dose of 15N-glycine as a tracer and urinary ammonia as end product. Subjects were studied in the fasting and feeding state, with different levels of protein and energy intake. The patients were underweight and presented lower plasma transthyretin and retinol-binding protein levels. When compared with controls, the kinetic studies showed patients to be hypometabolic in the fasting (D0) state and with the control diet [D1 = (0.85 g of protein/ 154 kJ) x kg-1.day-1]. However, when corrected by body weight, the kinetic differences between groups disappeared, whereas the N-retention in the feeding state showed better results for the patients due mainly to their efficient breakdown decrease. When fed high-level protein or energy diets [D1 = (0.9 g protein/195 kJ) and D3 = (1.56 g protein/158 kJ) x kg-1.day-1], the patients showed D0 = D1 = D2 < D3 for N-flux and (D0 = D1) < D3 (D2 is intermediary) for protein synthesis. Thus, the present data suggest that the remaining mass of the undernourished mild cirrhotic patients has fairly good protein synthesis activity and also that protein, rather than energy intake, would be the limiting factor for increasing their whole-body protein synthesis.


Assuntos
Proteínas Alimentares/administração & dosagem , Ingestão de Energia , Glicina , Cirrose Hepática Alcoólica/complicações , Desnutrição Proteico-Calórica/metabolismo , Proteínas/metabolismo , Adulto , Amônia/urina , Proteínas Sanguíneas/metabolismo , Jejum , Alimentos , Humanos , Cirrose Hepática Alcoólica/sangue , Masculino , Pessoa de Meia-Idade , Nitrogênio/metabolismo , Isótopos de Nitrogênio , Pré-Albumina/metabolismo , Desnutrição Proteico-Calórica/etiologia , Proteínas de Ligação ao Retinol/metabolismo , Proteínas Plasmáticas de Ligação ao Retinol
9.
Arq Gastroenterol ; 29(4): 128-36, 1992.
Artigo em Português | MEDLINE | ID: mdl-1340747

RESUMO

The dietary protein assimilation by cirrhotic undernourished patients (lower lean body mass and plasma TBPA and RBP levels) was investigated in five-adult male subjects suffering from histologically diagnosed liver cirrhosis, in its clinically mild stage (Child-Turcotte-Pugh grade A). During the 9 day-dietary study the patients received orally a sequence of complete-regional diets containing different protein-energy compositions identified as (g prot/Cal/kg/day): D0 = 0.42/20.9; D1 = 0.91/37.5; D2 = 0.99/47.9 and D3 = 1.60/40.5. The respective N-balance values (g/day) found were (mean +/- SD): low protein calorie (D0) = -4.24 +/- 2.46; normal protein calorie (D1) = 0.66 +/- 1.99; normal protein-high calorie (D2) = 1.14 +/- 2.54; high protein normal calorie (D3) = 5.12 +/- 2.48. The correspondent urea-N output (g/kg/day) were D0 = 0.22 +/- 0.100; D1 = 0.238 +/- 0.099; D = 0.20 +/- 0.063 and D3 = 0.310 +/- 0.121. The present data thus suggest that protein rather than energy intake would be the limited factor for increasing the N-retention in (mild) cirrhotic patients whom tolerate well dietary protein at either normal or elevated levels.


Assuntos
Proteínas Alimentares/metabolismo , Cirrose Hepática/metabolismo , Nitrogênio/metabolismo , Estado Nutricional , Adulto , Índice de Massa Corporal , Proteínas Alimentares/administração & dosagem , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/dietoterapia , Masculino , Pessoa de Meia-Idade , Estudos de Amostragem
10.
Rev Saude Publica ; 26(1): 27-33, 1992 Feb.
Artigo em Português | MEDLINE | ID: mdl-1307418

RESUMO

The calcium-intake relationship with other alimentary and anthropometric variables was investigates in a group of 60 adult (19-75 year-old) subjects, 50 females and 10 males, with essential arterial hypertension (DAP > 90 mmHg). The calcium intake was assessed by three different protocols: 24-hour food intake recall, food-frequency questionnaire and 3 day self-food intake register, repeated along with anthropometric measurements on three different occasions (2-15 month-intervals). The calcium intake assessed by the three methods, as well as the anthropometric data, were statistically similar on all three occasions. The mean data were then compared with those form the control, composed of 75 healthy subjects matched with the hypertensive group by age and sex. The patients ingested less calcium (mean +/- SD) than the controls on the daily (517 +/- 271 x 740 +/- 353 mg/d) and body-weight (8.1 +/- 5.0 x 11.4 +/- 5.9 mg/kg/d) basis. Among the males the calcium intake was the only difference found between groups and could be attributed to the lower intake of calcium-rich foods. The hypertensive females showed also higher lean-body mass (Body-mass index and arm muscle circumference). Thus the calcium intake discriminated both groups being associated with changes in other nutritional parameters only in females.


Assuntos
Cálcio da Dieta/administração & dosagem , Hipertensão/metabolismo , Adulto , Idoso , Antropometria , Pressão Sanguínea , Inquéritos sobre Dietas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais
11.
Arq Gastroenterol ; 28(3): 86-92, 1991.
Artigo em Português | MEDLINE | ID: mdl-1843243

RESUMO

The nutritional assessment by 24 hour-dietary recall, anthropometry and blood-components measurements was undertaken in 23 adult patients, 17 males and 6 females suffering of chronic diarrhea from pancreatitis (30%), inflammatory bowel disease (22%), short intestine syndrome (9%) and unknown diarrhea (35%). The nutritional assessment was done at the entry and repeated at the discharge of the hospitalization that averaged 35 days, during which the patients received specific medical treatment along with obstipating diets. The hospitalization resulted in overall improvement of the patients either clinically by reducing their defecation rate or nutritionally by increasing their protein-energy intake and the values of anthropometry and blood components (albumin, free-tryptophan and lymphocytes). When the patients where divided into two groups based on their fecal-fat output one could note the better nutritional response of the group showing steatorrhea than the non-steatorrhea group, with the serum albumin and the arm-muscle circumference being discriminatory between groups. However even in the better recovered patients the indicative values of a satisfactory nutritional status were not accomplished. Thus, these data suggest that besides the overall nutritional improvement seen in the studied chronic diarrhea patients the full-nutrition recovering would demand either or both a longer hospitalization and/or an early-aggressive nutritional support.


Assuntos
Diarreia/dietoterapia , Distúrbios Nutricionais/dietoterapia , Estado Nutricional , Adulto , Doença Crônica , Diarreia/tratamento farmacológico , Diarreia/etiologia , Ingestão de Energia , Feminino , Humanos , Doenças Inflamatórias Intestinais/complicações , Masculino , Pessoa de Meia-Idade , Avaliação Nutricional , Distúrbios Nutricionais/etiologia , Pancreatite/complicações , Síndrome do Intestino Curto/complicações
12.
Health Educ Q ; 8(4): 348-58, 1981.
Artigo em Inglês | MEDLINE | ID: mdl-7333856

RESUMO

In September, 1974, the Kaiser-Permanente Medical Center in Santa Clara, California, and the West Valley Community College District entered into cooperative planning for delivery of consumer health education. Two months later, the first five classes commenced with a total enrollment of 53 persons, all of whom were HMO members. Seven years later, this joining HMO-community college health education program entitled More Effective Living (MEL) contains over 50 different class titles, is offered cooperatively by two Kaiser-Permanente facilities and three locally-based community colleges, is scheduled in three academic semester time periods spanning 12 months and, is expected to serve an estimated 760 HMO members and community residents in the Spring 1981 semester. Although this paper addresses the HMO-community college partnership primarily from an administrative perspective, some background information is given to explain the basic concepts of the program design. For health educators, particularly those working in medical care, partnership with a community organization can be an effective way to deliver health education to a target population at minimal cost.


Assuntos
Educação em Saúde/organização & administração , Sistemas Pré-Pagos de Saúde/organização & administração , Universidades/organização & administração , California , Custos e Análise de Custo , Currículo , Humanos , Modelos Teóricos , Afiliação Institucional
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