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1.
Ann Oncol ; 22(10): 2216-26, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21325445

RESUMO

BACKGROUND: The International Breast Cancer Study Group Trial VIII compared long-term efficacy of endocrine therapy (goserelin), chemotherapy [cyclophosphamide, methotrexate and fluorouracil (CMF)], and chemoendocrine therapy (CMF followed by goserelin) for pre/perimenopausal women with lymph-node-negative breast cancer. PATIENTS AND METHODS: From 1990 to 1999, 1063 patients were randomized to receive (i) goserelin for 24 months (n = 346), (ii) six courses of 'classical' CMF (cyclophosphamide, methotrexate, 5-fluorouracil) chemotherapy (n = 360), or (iii) six courses of CMF plus 18 months goserelin (CMF→ goserelin; n = 357). Tumors were classified as estrogen receptor (ER) negative (19%), ER positive (80%), or ER unknown (1%); 19% of patients were younger than 40. Median follow-up was 12.1 years. RESULTS: For the ER-positive cohort, sequential therapy provided a statistically significant benefit in disease-free survival (DFS) (12-year DFS = 77%) compared with CMF alone (69%) and goserelin alone (68%) (P = 0.04 for each comparison), due largely to the effect in younger patients. Patients with ER-negative tumors whose treatment included CMF had similar DFS (12-year DFS CMF = 67%; 12-year DFS CMF→ goserelin = 69%) compared with goserelin alone (12-year DFS = 61%, P= NS). CONCLUSIONS: For pre/perimenopausal women with lymph-node-negative ER-positive breast cancer, CMF followed by goserelin improved DFS in comparison with either modality alone. The improvement was the most pronounced in those aged below 40, suggesting an endocrine effect of prolonged CMF-induced amenorrhea.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Adulto , Antineoplásicos Hormonais/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Quimioterapia Adjuvante , Ciclofosfamida/administração & dosagem , Intervalo Livre de Doença , Feminino , Fluoruracila/administração & dosagem , Gosserrelina/administração & dosagem , Humanos , Linfonodos/patologia , Metotrexato/administração & dosagem , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Pré-Menopausa , Receptores de Estrogênio/biossíntese
2.
Ann Oncol ; 16(5): 716-25, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15817593

RESUMO

BACKGROUND: Controversy persists about whether chemotherapy benefits all breast cancer patients. PATIENTS AND METHODS: In the International Breast Cancer Study Group (IBCSG) trial VII, 1212 postmenopausal patients with node-positive disease were randomized to receive tamoxifen for 5 years or tamoxifen plus three concurrent courses of cyclophosphamide, methotrexate and 5-fluorouracil ('classical' CMF) chemotherapy, either early, delayed or both. In IBCSG trial IX, 1669 postmenopausal patients with node-negative disease were randomized to receive either tamoxifen alone or three courses of adjuvant classical CMF prior to tamoxifen. Results were assessed according to estrogen receptor (ER) content of the primary tumor. RESULTS: For patients with node-positive, ER-positive disease, adding CMF either early, delayed or both reduced the risk of relapse by 21% (P=0.06), 26% (P=0.02) and 25% (P=0.02), respectively, compared with tamoxifen alone. There was no difference in disease-free survival when CMF was given prior to tamoxifen in patients with node-negative, ER-positive tumors. CONCLUSIONS: CMF given concurrently (early, delayed or both) with tamoxifen was more effective than tamoxifen alone for patients with node-positive, endocrine-responsive breast cancer, supporting late administration of chemotherapy even after commencement of tamoxifen. In contrast, sequential CMF and tamoxifen for patients with node-negative, endocrine-responsive disease was ineffective.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias Hormônio-Dependentes/tratamento farmacológico , Tamoxifeno/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/mortalidade , Neoplasias da Mama/cirurgia , Intervalos de Confiança , Ciclofosfamida/uso terapêutico , Relação Dose-Resposta a Droga , Esquema de Medicação , Quimioterapia Combinada , Feminino , Fluoruracila/uso terapêutico , Humanos , Mastectomia Segmentar , Metotrexato/uso terapêutico , Pessoa de Meia-Idade , Neoplasias Hormônio-Dependentes/mortalidade , Neoplasias Hormônio-Dependentes/cirurgia , Pós-Menopausa , Probabilidade , Prognóstico , Valores de Referência , Medição de Risco , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento
3.
Mol Biochem Parasitol ; 136(2): 257-64, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15478804

RESUMO

We have isolated and expressed a cDNA from the parasitic nematode Trichinella spiralis encoding a novel secreted nucleotidase which catalyses the hydrolysis of nucleoside 5'-diphosphates and 5'-monophosphates, but not 5'-triphosphates. The full length cDNA encodes a protein of 550 amino acids with an N-terminal signal peptide, but lacking a C-terminal signature sequence for addition of a glycosyl phosphatidylinositol (GPI) anchor. Expression in Pichia pastoris resulted in the secretion of an active enzyme with the catalytic properties of both a Mg2+-dependent diphosphohydrolase/apyrase and a 5'-nucleotidase. The protein sequence is homologous to 5'-nucleotidases from a wide variety of organisms but contains no sequences specifically conserved in apyrases, suggesting that it is a representative of a new class of secreted nucleotidase. The enzyme was essentially monospecific for AMP among the nucleoside 5'-monophosphates and catalysed the hydrolysis of nucleoside 5'-diphosphates in the order of UDP >> ADP. The diphosphatase activity was dependent on the presence of magnesium ions and a reducing agent, while the 5'-nucleotidase activity was enhanced by these additions. Kinetic analyses indicated that the enzyme exhibits allosteric behaviour. Determination of the number of active sites suggested that catalysis of the two different reactions occurs at the same active site. The data are discussed in terms of regulation of host purinergic signalling during infection.


Assuntos
5'-Nucleotidase/genética , 5'-Nucleotidase/metabolismo , Trichinella spiralis/enzimologia , Trichinella spiralis/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Catálise , Clonagem Molecular , DNA Complementar/genética , DNA de Helmintos/genética , Expressão Gênica , Genes de Helmintos , Cinética , Dados de Sequência Molecular , Pichia/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Homologia de Sequência de Aminoácidos
5.
Emerg Infect Dis ; 9(7): 794-9, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12890319

RESUMO

Seven alligators were submitted to the Tifton Veterinary Diagnostic and Investigational Laboratory for necropsy during two epizootics in the fall of 2001 and 2002. The alligators were raised in temperature-controlled buildings and fed a diet of horsemeat supplemented with vitamins and minerals. Histologic findings in the juvenile alligators were multiorgan necrosis, heterophilic granulomas, and heterophilic perivasculitis and were most indicative of septicemia or bacteremia. Histologic findings in a hatchling alligator were random foci of necrosis in multiple organs and mononuclear perivascular encephalitis, indicative of a viral cause. West Nile virus was isolated from submissions in 2002. Reverse transcription-polymerase chain reaction (RT-PCR) results on all submitted case samples were positive for West Nile virus for one of four cases associated with the 2001 epizootic and three of three cases associated with the 2002 epizootic. RT-PCR analysis was positive for West Nile virus in the horsemeat collected during the 2002 outbreak but negative in the horsemeat collected after the outbreak.


Assuntos
Jacarés e Crocodilos/virologia , Febre do Nilo Ocidental/veterinária , Vírus do Nilo Ocidental/isolamento & purificação , Animais , Anticorpos Antivirais/isolamento & purificação , Infecções Bacterianas/complicações , Infecções Bacterianas/veterinária , Feminino , Cavalos/virologia , Masculino , RNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Febre do Nilo Ocidental/complicações , Febre do Nilo Ocidental/diagnóstico , Febre do Nilo Ocidental/imunologia , Vírus do Nilo Ocidental/genética , Vírus do Nilo Ocidental/imunologia
6.
Mol Biochem Parasitol ; 123(2): 125-34, 2002 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-12270628

RESUMO

A third variant of acetylcholinesterase (AChE A) secreted by the parasitic nematode Nippostrongylus brasiliensis has been isolated which shows 63-64% identity to AChE B and AChE C, with a truncated carboxyl terminus and a short internal insertion relative to AChEs from other species. Three of the fourteen aromatic residues which line the active site gorge in Torpedo AChE are substituted by non-aromatic residues (Y70T, W279D and F288M). All three enzymes have 8 cysteine residues in conserved positions, including 6 which have been implicated in disulphide bonds in other AChEs. Phylogenetic analysis suggests that these enzymes form a distinct group which evolved after speciation and are most closely related to ACE-2 of Caenorhabditis elegans. Recombinant AChE A secreted by Pichia pastoris was monomeric and hydrophilic, with a substrate preference for acetylthiocholine and negligible activity against butyrylthiocholine. A model structure of AChE A built from the coordinates of the Torpedo californica AChE suggests that W345 (F331 in Torpedo) limits the docking of butyrylcholine. This model is consistent with mutational analysis of the nematode enzymes. Expression of AChE A is regulated at the transcriptional level independently of the other 2 secreted variants, with maximal expression by fourth stage larvae and young adult worms. These enzymes thus appear to represent an unusual family of AChEs with conserved structural features which operate outside the normal boundaries of known functions in regulation of endogenous neurotransmitter activity.


Assuntos
Acetilcolinesterase/genética , Nippostrongylus/enzimologia , Acetilcolinesterase/química , Acetilcolinesterase/metabolismo , Acetiltiocolina/metabolismo , Sequência de Aminoácidos , Animais , Butiriltiocolina/metabolismo , Clonagem Molecular , DNA Complementar , Modelos Moleculares , Dados de Sequência Molecular , Nippostrongylus/genética , Filogenia , Pichia/metabolismo , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Especificidade da Espécie , Especificidade por Substrato
7.
J Clin Oncol ; 19(21): 4141-9, 2001 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11689582

RESUMO

PURPOSE: We investigated tumor- and patient-related features that might influence the response to perioperative chemotherapy (PeCT) compared with no adjuvant therapy for patients with node-negative breast cancer. PATIENTS AND METHODS: A total of 1,275 patients were randomized to either no adjuvant treatment (427 patients) or PeCT (848 patients). The following variables thought to have prognostic significance were evaluated: grade, tumor size, estrogen (ER) and progesterone receptor (PgR) content (absent; low, 1 to 9 fmol/mg cytosol protein; or positive, > or = 10 fmol/mg cytosol protein), c-erbB-2 overexpression, menopausal status, and age. Cox proportional hazards regression models were used to assess the relative influence of these factors to predict the effect of PeCT on disease-free survival (DFS). Median follow-up was 13.5 years. RESULTS: The 10-year DFS percentage for 692 premenopausal patients did not significantly differ between the PeCT and no-adjuvant-treatment groups: 61% and 59%, respectively (relative risk [RR], 0.95; 95% confidence interval [CI], 0.75 to 1.20; P = .70). No predictive factors were identified. For 583 postmenopausal patients, 10-year DFS percentages for the groups were 63% and 58%, respectively (RR, 0.75; 95% CI, 0.58 to 0.93; P = .03). The absence of expression of ER, PgR, or both ER and PgR was the most important factor predicting improved outcome with PeCT among postmenopausal patients. The 10-year DFS percentages were 85% and 53% for the steroid hormone receptor-absent cohort of treated and untreated patients, respectively (RR, 0.18; 95% CI, 0.06 to 0.49; P = .0009). CONCLUSION: The role of PeCT should be explored for patients whose primary tumors do not express steroid hormone receptors, because it is likely that early initiation of treatment is exclusively relevant for such patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/cirurgia , Quimioterapia Adjuvante , Ciclofosfamida/administração & dosagem , Feminino , Fluoruracila/administração & dosagem , Humanos , Mastectomia , Metotrexato/administração & dosagem , Pessoa de Meia-Idade , Pós-Menopausa , Modelos de Riscos Proporcionais , Receptor ErbB-2/metabolismo , Análise de Sobrevida
8.
Exp Brain Res ; 119(2): 131-40, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9535562

RESUMO

In macaque monkeys, aspiration but not excitotoxic lesions of the medial temporal lobe limbic structures, the amygdala and hippocampus, produce a severe impairment in visual recognition memory. Furthermore, certain ventromedial cortical regions, namely the rhinal (i.e., entorhinal and perirhinal) cortex, are now known to be critical for visual recognition memory. Because the route taken by temporal cortical efferent fibers, especially perirhinal efferents, passes nearby the amygdala, it is possible that inadvertent damage to these fibers is produced by the aspirative but not the excitotoxic process, thereby accounting at least in part for the different behavioral outcomes of the two types of lesion. To test this idea, we assessed the integrity of the rhinal corticothalamic projection system after aspiration lesions of the amygdala. Three rhesus monkeys with unilateral amygdala removals received bilaterally symmetrical injections of a retrograde fluorescent tracer into the medial portion of the mediodorsal nucleus of the thalamus. Retrogradely labeled cells were identified using conventional fluorescence microscopy techniques. In all three cases, the rhinal cortex of the intact hemispheres contained moderate numbers of retrogradely labeled cells. By contrast, the rhinal cortex of the amygdalectomized hemispheres consistently contained few retrogradely labeled cells, and a direct comparison of the two hemispheres showed this difference to be statistically significant. A similar asymmetric pattern was observed for area TE but not for the cortex lining the dorsal bank of the superior temporal sulcus, nor for the rostral cingulate motor area, which was examined as a control. The results indicate that aspiration lesions of the amygdala not only remove the cell bodies of the amygdala, as intended, but also inadvertently disrupt projection fibers arising from cells in the rhinal cortex and area TE that pass nearby or through the amygdala en route to the thalamus. Behavioral studies examining the effects of aspiration lesions of the amygdala in nonhuman primates need to take these findings into consideration.


Assuntos
Tonsila do Cerebelo/fisiopatologia , Córtex Cerebral/fisiopatologia , Sistema Límbico/fisiopatologia , Sucção , Transmissão Sináptica/fisiologia , Tálamo/fisiopatologia , Animais , Encefalopatias/etiologia , Encefalopatias/fisiopatologia , Mapeamento Encefálico , Inalação , Macaca mulatta
9.
Eur J Biochem ; 239(1): 132-7, 1996 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-8706697

RESUMO

We present here the complete primary structure of human gp330, the human variant of the principal kidney autoantigen causing Heymann membranous glomerulonephritis in rats. The deduced 4655 amino acid residues give a calculated molecular mass of 519636 Da for the mature protein and consists of a probable 25-amino-acid N-terminal signal peptide sequence, an extracellular region of 4398 amino acids, a single transmembrane-spanning domain of 23 amino acids, and an intracellular C-terminal region of 209 amino acid residues. Three types of cysteine-rich repeats characteristic of the low density lipoprotein receptor (LDLR) superfamily are present in human gp330. In the extracellular region, there are a total of 36 LDLR ligand-binding repeats, comprising four distinct domains, 16 growth factor repeats separated by eight YWTD spacer regions, and one epidermal growth factor-like repeat. No consensus cleavage sequence for the processing endoprotease furin is detected in human gp330. The intracellular tail contains not only two copies of the F(X)NPXY coated-pit mediated internalization signal characteristic of LDLR superfamily members, but also intriguing and potentially functional motifs including several Src-homology 3 recognition motifs, one Src-homology 2 recognition motif for the p85 regulatory subunit of phosphatidylinositol 3-kinase, and additional sites for protein kinase C, casein kinase II and cAMP-/cGMP-dependent protein kinase. There is approximately 77% amino acid identity between human and rat gp330 with minor differences between the extracellular and intracellular regions. Recently gp330 has been implicated in Ca2+ regulation in the parathyroid, the placenta, and the renal tubule, but its overall physiological and pathological role still remains uncertain.


Assuntos
Proteínas de Ligação ao Cálcio/genética , Glicoproteínas de Membrana/genética , Transdução de Sinais , Sequência de Aminoácidos , Animais , Proteínas de Ligação ao Cálcio/metabolismo , Clonagem Molecular , DNA Complementar , Complexo Antigênico da Nefrite de Heymann , Humanos , Glomérulos Renais/imunologia , Glicoproteínas de Membrana/metabolismo , Dados de Sequência Molecular , Peso Molecular , Ratos , Homologia de Sequência de Aminoácidos , Domínios de Homologia de src
10.
J Cardiovasc Surg (Torino) ; 36(5): 423-8, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8522555

RESUMO

We investigated the effect of intraoperative autologous blood sequestration (IABS), an old blood conservation method, on transfusion requirements for homologous packed red blood cells (PRBC), platelets, and fresh frozen plasma (FFP) for patients undergoing coronary bypass surgery. This non-randomized retrospective study involved 204 patients who underwent isolated primary coronary artery bypass grafting (CABG). In 140 patients (IABS Group), autologous heparinized whole blood was removed intraoperatively via aortic cannula before bypass and retransfused at the conclusion of extracorporeal circulation. In 64 control patients, no IABS was performed. Demographic characteristics and operative and perioperative variables for both groups were similar (p > 0.05). In 140 patients, the mean sequestered blood volume was 1430 ml (range = 700-2100 ml). The banked PRBC requirement during hospitalization was 1.91 units in the No IABS Group and 2.25 units for the IABS Group (p = 0.2957). The need for platelet transfusion was 3.06 units in the No IABS Group and 1.09 units in the IABS Group (p = 0.0003). In the No IABS Group, 1.31 units of FFP was transfused and in the IABS Group, 0.49 units was transfused (p = 0.0004). To identify possible confounding factors, we performed a multivariate Poisson regression analysis for the 22 patient variables by a forward stepwise procedure. Regression analysis indicated that IABS did not alter the need for PRBC transfusion (p = 0.6194) but adjusted differences did confirm that IABS was associated with decreased need for transfusion of platelets and FFP (p = 0.0001 and p = 0.0002, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Transfusão de Sangue Autóloga , Ponte de Artéria Coronária , Transfusão de Eritrócitos , Humanos , Período Intraoperatório , Masculino , Pessoa de Meia-Idade , Plasma , Transfusão de Plaquetas , Análise de Regressão , Estudos Retrospectivos
11.
Growth Dev Aging ; 58(3): 119-33, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7868303

RESUMO

The effects of dietary calcium intake on the composition and turnover of the femur and humerus were compared in two mouse strains that differ in growth kinetics and phorbol ester-induced signal transduction. C57BL/6 (control) and SENCAR (large) mice were fed calcium-deficient (0.02% Ca) or -sufficient (0.6% Ca) diets from 10 to 14 weeks of age. Bone mass was determined gravimetrically. Calcium and magnesium were determined by atomic absorption spectrophotometry, while phosphorus was determined colorimetrically. Turnover was estimated pharmacokinetically in [3H]tetracycline-labeled bone. Femur and humerus lengths, breadths, masses, and ash and mineral contents were higher in SENCAR mice than in C57BL/6 mice at 10 weeks of age and after being fed 0.02% or 0.6% calcium diets for four weeks. Relative formation was higher in C57BL/6 mice than in SENCAR mice from 10 to 14 weeks of age, resulting in greater net increases (0.6% Ca diet) or lower net decreases (0.02% Ca diet) in the calcium contents of the femurs and humeri of C57BL/6 mice, compared to SENCAR mice. Calcium-deficient feeding stimulated higher relative rates of bone resorption in both strains and affected the net changes in bone calcium contents. Thus, hereditary factors in SENCAR and C57BL/6 mice that regulate formation rates, not resorption rates or the response to dietary calcium intake, appear to modulate net changes in humerus and femur calcium contents at maturity.


Assuntos
Cálcio da Dieta/administração & dosagem , Cálcio/deficiência , Fêmur/crescimento & desenvolvimento , Úmero/crescimento & desenvolvimento , Maturidade Sexual/fisiologia , Fatores Etários , Animais , Peso Corporal/fisiologia , Reabsorção Óssea , Cálcio/metabolismo , Dieta , Fêmur/efeitos dos fármacos , Fêmur/metabolismo , Úmero/efeitos dos fármacos , Úmero/metabolismo , Magnésio/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos SENCAR , Fósforo/metabolismo
12.
Proc Soc Exp Biol Med ; 203(1): 64-73, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8475140

RESUMO

The effects of dietary calcium intake on vertebral bone mass, composition, and turnover (calcium deposition and resorption) were determined in 10- and 14-week-old C57BL/6 (small) and SENCAR (large) mice. Total vertebral mass, percent ash, calcium, magnesium, and phosphorus were higher in SENCAR mice than in C57BL/6 mice at 10 weeks of age and after being fed 0.02% or 0.6% dietary calcium for 4 additional weeks. Relative calcium deposition was higher in C57BL/6 than in SENCAR mice, while relative calcium resorption was similar in both strains. The rate of resorption was higher in mice fed 0.02% dietary calcium than in those fed 0.6% dietary calcium. Thus, C57BL/6 mice gained vertebral calcium, while it remained unchanged or declined in SENCAR mice under conditions of both calcium depletion and calcium repletion. Serum osteocalcin (an index of bone formation) was higher in C57BL/6 mice than in SENCAR mice. Mathematically significant correlations between osteocalcin levels and vertebral calcium resorption and the net vertebral calcium loss were observed only in SENCAR mice. The serum calcitonin concentration was correlated with the amount of vertebral calcium resorbed in SENCAR mice, but not in C57BL/6 mice. Thus, vertebral resorption and formation are more tightly coupled in 10- to 14-week-old SENCAR mice than in C57BL/6 mice. In addition, remodeling appears to dominate vertebral calcium dynamics in SENCAR mice, while growth dominates in C57BL/6 mice during this period. Rodents have frequently been dismissed as potential models of bone aging based on the expectation that continued growth, rather than remodeling, dominates skeletal dynamics. These data clearly demonstrate that increases in body mass ("growth") are not invariably associated with continued vertebral growth. In this murine model, both heredity and dietary calcium intake modulate vertebral bone mass, turnover dynamics, and composition at sexual maturity. These differences in the development and regulation of vertebral bone mass in small C57BL/6 and large SENCAR mice suggest that animal, as well as clinical, models provide useful insights into the cellular and hormonal mechanisms of somatotype-dependent vertebral growth.


Assuntos
Densidade Óssea , Osso e Ossos/metabolismo , Calcitonina/sangue , Cálcio/deficiência , Cálcio/farmacologia , Camundongos Endogâmicos/fisiologia , Osteocalcina/sangue , Análise de Variância , Animais , Densidade Óssea/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Cálcio/metabolismo , Comportamento Alimentar , Magnésio/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL/fisiologia , Fósforo/metabolismo , Especificidade da Espécie , Coluna Vertebral/química
14.
Arch Latinoam Nutr ; 38(3): 543-67, 1988 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-3155250

RESUMO

The disaccharide lactose, the principal carbohydrate of animal milks, requires the enzyme lactase to split it to glucose and galactose. Undigested lactose passes to the colon where fermentation produces hydrogen and short-chain fatty acids that can cause abdominal distention, pain and sometimes diarrhea. Persistence of intestinal lactase after early childhood, is inherited as a highly-penetrant autosomal dominant genetic characteristic. On the basis of a review of over 560 references, all available data on the primary loss of intestinal lactase in Latin American populations are presented in tabular form. Prevalence of lactose non-digesters in Latin American populations ranges from 45% to 100%. However, this is not a reliable predictor of the acceptability of milk and milk products containing lactose. Milk is being used successfully for the supplementary feeding of children worldwide, and most lactose non-digesters can tolerate at least 240 ml of milk or the lactose equivalent in other products. Lactose maldigestion does not interfere with the absorption of the protein and essential micronutrients in milk. Information is provided on the lactose content of milk and milk products, on the usual milk consumption of Latin American populations, and on worldwide experimental and field observations of milk acceptability. Both adaptation to continued use of milk and milk products and relationships of milk use to various disease states in which intestinal lactase activity may be reduced are discussed. Some types of yoghurts are better tolerated because of the lactase activity of the bacteria used in their fermentation. For unusually intolerant individuals commercial enzyme preparations are available for addition to milk products but for most persons the additional cost is unnecessary.


Assuntos
Intolerância à Lactose/complicações , Leite , Distúrbios Nutricionais/prevenção & controle , Adulto , Fatores Etários , Animais , Criança , Pré-Escolar , Proteínas Alimentares/administração & dosagem , Dispepsia/etiologia , Comportamento Alimentar , Humanos , Lactente , Recém-Nascido , Intolerância à Lactose/epidemiologia , América Latina/epidemiologia , Leite/efeitos adversos , Distúrbios Nutricionais/dietoterapia , Distúrbios Nutricionais/etiologia , beta-Galactosidase/biossíntese , beta-Galactosidase/deficiência , beta-Galactosidase/genética
15.
J Nutr ; 113(12): 2524-34, 1983 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6686255

RESUMO

Six healthy young male M.I.T. students participated in a metabolic study to assess the capacity of a soy protein concentrate (STAPRO-3200) to serve as the sole source of dietary protein for long-term maintenance of protein nutritional status. Following an initial 9-day period, during which the subjects received an egg-protein, formula diet supplying 1.5 g protein per kilogram per day, the soy protein was given at a level of 0.8 g protein (N X 6.25) per kilogram per day for 82 days. Throughout, nitrogen balances were measured, and at intervals of 3 to 4 weeks, blood chemistries were determined, and evaluations of physical performance were undertaken. In addition measurements were made of zinc absorption and balance and of iron absorption, with the aid of 70Zn and 58Fe. Mean nitrogen balances were slightly positive for all subjects and the protein source was judged to support adequately maintenance of protein nutritional status, confirmed by the absence of changes in relevant blood parameters and maintenance of performance in the exercise tests. Mean zinc absorption was 23% of intake and did not change during the 82-day soy period and crude zinc balances remained slightly positive throughout. Iron intake was solely from the soy concentrate, and each meal was supplemented with ascorbic acid. Iron absorption was highly variable between and within subjects, as determined by the stable isotope balance procedure. Associated with the withdrawal of blood for purposes of monitoring the subjects, serum ferritin declined indicating a reduction in iron stores. These blood changes were used to approximate iron absorption and it was estimated to be 16%. It is concluded that well-processed soy concentrate can serve as the sole source of nitrogen and essential amino acids for long-term maintenance in adult humans.


Assuntos
Proteínas Alimentares/metabolismo , Glycine max , Fenômenos Fisiológicos da Nutrição , Proteínas de Plantas/metabolismo , Absorção , Adolescente , Adulto , Proteínas do Ovo/metabolismo , Humanos , Ferro/metabolismo , Masculino , Nitrogênio/metabolismo , Valor Nutritivo , Aptidão Física , Fatores de Tempo , Zinco/metabolismo
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