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2.
Phys Rev Lett ; 129(8): 080401, 2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-36053678

RESUMO

The Majorana Demonstrator neutrinoless double-beta decay experiment comprises a 44 kg (30 kg enriched in ^{76}Ge) array of p-type, point-contact germanium detectors. With its unprecedented energy resolution and ultralow backgrounds, Majorana also searches for rare event signatures from beyond standard model physics in the low energy region below 100 keV. In this Letter, we test the continuous spontaneous localization (CSL) model, one of the mathematically well-motivated wave function collapse models aimed at solving the long-standing unresolved quantum mechanical measurement problem. While the CSL predicts the existence of a detectable radiation signature in the x-ray domain, we find no evidence of such radiation in the 19-100 keV range in a 37.5 kg-y enriched germanium exposure collected between December 31, 2015, and November 27, 2019, with the Demonstrator. We explored both the non-mass-proportional (n-m-p) and the mass-proportional (m-p) versions of the CSL with two different assumptions: that only the quasifree electrons can emit the x-ray radiation and that the nucleus can coherently emit an amplified radiation. In all cases, we set the most stringent upper limit to date for the white CSL model on the collapse rate, λ, providing a factor of 40-100 improvement in sensitivity over comparable searches. Our limit is the most stringent for large parts of the allowed parameter space. If the result is interpreted in terms of the Diòsi-Penrose gravitational wave function collapse model, the lower bound with a 95% confidence level is almost an order of magnitude improvement over the previous best limit.

3.
Gut ; 42(4): 555-9, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9616320

RESUMO

BACKGROUND: Surgery in patients with malignant bile duct obstruction is associated with high postoperative morbidity and mortality. Tumour necrosis factor alpha (TNF-alpha) plays a key role in the pathogenesis of these complications. AIMS: To determine the effect of biliary drainage on plasma concentrations of TNF-alpha, its soluble circulating receptors (sTNFr), and other proinflammatory cytokines. METHODS: Plasma concentrations of TNF-alpha, sTNFr-P75, interleukin 6 (IL-6), and IL-1 alpha were measured in 25 patients with malignant bile duct obstruction before and after endoscopic stent insertion. RESULTS: Mean serum bilirubin was 157 mumol/l before stent insertion and 35.2 mumol/l one week post stent insertion. There was complete relief of jaundice in 77% of patients by four weeks. Plasma concentrations of TNF-alpha and IL-1 alpha were below the detection limit of the assays in all samples. Median plasma sTNFr-P75 in the cancer patients was 960 ng/l (range 400-6600), before stent insertion and remained unchanged at one and four weeks after stenting. Plasma sTNFr-P75 in cancer patients was significantly higher (p < 0.01) than in healthy controls (250 (200-650) ng/l). Before stent insertion, plasma IL-6 concentrations were detectable (above 5 ng/l) in 17 (68%) patients. After relief of biliary obstruction IL-6 levels fell from a prestent median of 13.2 to less than 5 ng/l at one week after stent insertion. Plasma concentrations of IL-6 were undetectable in 76% of patients at this time. CONCLUSION: Activation of the TNF/sTNFr complex is unchanged after biliary drainage in patients with malignant bile duct obstruction. This may explain why preoperative drainage does not influence the high morbidity and mortality associated with surgery in these patients.


Assuntos
Colestase/etiologia , Colestase/cirurgia , Neoplasias Pancreáticas/complicações , Receptores do Fator de Necrose Tumoral/sangue , Stents , Fator de Necrose Tumoral alfa/análise , Colestase/sangue , Colestase/imunologia , Ensaio de Imunoadsorção Enzimática , Humanos , Ensaio Imunorradiométrico , Interleucina-1/análise , Interleucina-6/análise , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/imunologia , Estatísticas não Paramétricas
5.
Int J Obes Relat Metab Disord ; 21(4): 274-9, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9130023

RESUMO

OBJECTIVE: To validate a variation of a well-established magnetic resonance imaging (MRI) technique to detect liver fat and use it to monitor liver fat changes after treatment with dexfenfluramine in men with non-insulin dependent diabetes mellitus (NIDDM). DESIGN: (a) Simple correlation study of MRI Liver Fat Index with liver biopsy results; (b) Open Study of 10 men with NIDDM treated with dexfenfluramine for 12 weeks in addition to their 'usual' therapy. SUBJECTS: (a) 19 patients (3F; 16M) with abnormal liver function tests undergoing liver biopsy; (b) 10 men, Body Mass Index (BMI) < 30, Waist to hip ratio (WHR) > 0.90 with poorly controlled NIDDM despite oral sulphonylurea therapy. MEASUREMENTS: (a) MRI liver fat; standard liver biopsy; (b) MRI visceral fat, MRI liver fat, euglycaemic clamp, plasma lipids, fasting glucose and c-peptide levels. RESULTS: In the validation group, there was a strong relationship between the MRI Liver Fat Index and histopathological assessment of the liver biopsies (r = 0.87, < 0.0001). During treatment with dexfenfluramine the mean Liver Fat Index reduced from 10.6 +/- 3.4 to 6.6 +/- 2.8 (P = 0.05). The reduction in Liver Fat Index correlated with the reduction in visceral fat (r = 0.84, P = 0.001) as well as with the improvement in insulin sensitivity (r = 0.62, P = 0.05). Using partial correlation analysis, the relationship between the change in visceral adipose tissue and the improvement in insulin sensitivity was weaker if the Liver Fat Index was kept constant (r = 0.76 decreased to r = 0.56). CONCLUSIONS: In this group of subjects MRI Liver Fat Index correlated well with liver fat as seen on biopsy. The Liver Fat Index reduced after 12 weeks therapy with dexfenfluramine suggesting a role for hepatic steatosis in the complex interaction between visceral adipose tissue and insulin sensitivity.


Assuntos
Diabetes Mellitus Tipo 2/patologia , Fígado Gorduroso/tratamento farmacológico , Fígado Gorduroso/patologia , Fenfluramina/uso terapêutico , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Adulto , Biópsia , Intervalos de Confiança , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/patologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Feminino , Humanos , Fígado/efeitos dos fármacos , Fígado/patologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Obesidade
6.
Gut ; 35(4): 467-70, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7513672

RESUMO

Palliative treatment is appropriate for most patients with cancer of the head of pancreas. Insertion of a biliary stent relieves jaundice and pruritus but it is not known if stenting affects other symptoms or changes the quality of life. Nineteen patients have completed a standard questionnaire to assess symptom relief and quality of life after stent insertion. After stenting there was complete relief of jaundice and pruritus. Furthermore, there was also considerable improvement in anorexia and indigestion. All patients had anorexia before stent insertion, this was moderate/severe in 13 (68.4%). Anorexia was significantly better (p < 0.01) a week after stenting and this benefit was maintained at 12 weeks (p < 0.01). Sixteen (84.2%) patients complained of indigestion before stenting, moderate/severe in 11 (57.9%). This was significantly better (p < 0.01) a week after stenting with complete relief in six at eight weeks (p < 0.01). Fifteen (78.9%) felt that their mood was good/very good before stent insertion and this was unchanged even at the 12 week assessment. A similar result was obtained for physical health and level of activity. In conclusion stent insertion not only relieves jaundice and pruritus in these patients but also improves other symptoms and quality of life. The considerable improvement in appetite after stenting was of particular benefit.


Assuntos
Colestase/cirurgia , Cuidados Paliativos , Neoplasias Pancreáticas/complicações , Qualidade de Vida , Stents , Afeto , Idoso , Anorexia/cirurgia , Colangiopancreatografia Retrógrada Endoscópica , Colestase/etiologia , Colestase/psicologia , Dispepsia/cirurgia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/psicologia , Prurido/cirurgia
7.
Gut ; 34(9): 1198-202, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8406153

RESUMO

Elemental diet is as effective as corticosteroids in the treatment of previously untreated Crohn's disease. It is unclear whether a poor nutritional state is a prerequisite for efficacy of elemental diet, whether previously treated patients respond as well, or how duration of remission using elemental diet compares with corticosteroid induced remission. Forty two patients with active Crohn's disease were stratified for nutritional state and randomised to receive Vivonex TEN 2.1 l/day for four weeks, or 0.75 mg prednisolone/kg/day for two weeks and subsequent reducing doses. Nine of 22 (41%) patients assigned to nutritional treatment were intolerant of the diet. Thirty patients completed four weeks treatment. Disease activity decreased on elemental diet from mean (SEM) 4.8 (0.9) to 1.7 (0.6), p < 0.05, and on prednisolone from 5.3 (0.5) to 1.9 (0.6), p < 0.05. For each treatment, nourished and malnourished patients responded similarly. Patients with longstanding disease responded as well as newly diagnosed patients. The probability of maintaining remission at six months was 0.67 after prednisolone, 0.28 after elemental diet, and at one year was 0.35 after prednisolone and 0.09 after elemental diet, p < 0.05. When tolerated, elemental diet is as effective in the short term as prednisolone in newly and previously diagnosed Crohn's disease, and its benefit is independent of nutritional state. The subsequent relapse rate after elemental diet induced remission, however, is greater than after treatment with prednisolone.


Assuntos
Doença de Crohn/dietoterapia , Doença de Crohn/tratamento farmacológico , Alimentos Formulados , Prednisolona/uso terapêutico , Adolescente , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Indução de Remissão
8.
Am J Psychiatry ; 147(8): 1075-7, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2375444

RESUMO

Urine volume and osmolality were studied in two schizophrenic patients with hyponatremia and six normal subjects after they smoked or ingested cigarettes. The results suggest that cigarette use may contribute to the development of hyponatremia by impairing water excretion.


Assuntos
Hiponatremia/etiologia , Nicotiana , Plantas Tóxicas , Psicologia do Esquizofrênico , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pica/complicações , Esquizofrenia/complicações , Fumar/efeitos adversos , Intoxicação por Água/complicações
9.
Gut ; 27 Suppl 1: 72-5, 1986 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3098645

RESUMO

Although many patients with inflammatory bowel disease are malnourished, the role of nutritional support is still controversial. It is universally accepted that with adequate nutritional support patients will put on weight and that their biochemical functions may improve; the question nevertheless remains: does this help the patient get over his or her disease more quickly and, more importantly, does this affect morbidity and mortality? There are several ways of providing nutritional support and all need careful evaluation.


Assuntos
Colite Ulcerativa/terapia , Doença de Crohn/terapia , Nutrição Enteral , Nutrição Parenteral Total , Humanos
10.
Environ Res ; 40(2): 499-517, 1986 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3732218

RESUMO

Rats were exposed by inhalation to 5 or 50 mg/m3 Mount St. Helens volcanic ash, to 50 mg/m3 quartz (positive controls), or to filtered room air (sham-exposed controls), for 6 hr/day, 5 days/week, for up to 24 months to investigate biological effects of chronic inhalation exposure to volcanic ash under controlled laboratory conditions. Exposure-related lung changes comprised accelerated respiratory frequency; alveolar macrophage accumulation; interstitial reaction; lymphoreticular reaction in peribronchiolar regions and in mediastinal lymph nodes; alveolar proteinosis in the 50- mg/m3 ash- or quartz-exposed groups; increase in fresh lung weights; decreased body weight and increased mortality in the quartz-exposed group; and epidermoid carcinomas especially in the quartz-exposed females and, to a lesser extent, in the 50-mg/m3 ash-exposed females. The observed changes reflect significant dose-response and agent-response relationships.


Assuntos
Poluentes Atmosféricos , Carbono/toxicidade , Pulmão/efeitos dos fármacos , Aerossóis , Animais , Câmaras de Exposição Atmosférica , Peso Corporal/efeitos dos fármacos , Carbono/metabolismo , Feminino , Pulmão/análise , Pulmão/patologia , Masculino , Quartzo/metabolismo , Quartzo/toxicidade , Ratos , Ratos Endogâmicos F344 , Respiração/efeitos dos fármacos , Silício/análise
11.
Br J Cancer ; 48(3): 329-34, 1983 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6351883

RESUMO

Twenty-eight patients with advanced life-threatening metastatic malignant melanoma were treated with high dose (140-260 mgm-2) intravenous melphalan and autologous bone marrow. Cyclophosphamide "priming" 300 mgm-2 i.v. was given to 19 patients one week previously and this resulted in clinical but not histological evidence of amelioration of gastrointestinal toxicity. In 11 patients (43%) there was evidence of tumour response to treatment and in 2 patients complete remissions were observed. However in most patients, responses were short-lived and no patient lived longer than 17 months from start of treatment or 24 months from first recorded evidence of distant metastatic disease.


Assuntos
Transplante de Medula Óssea , Melanoma/terapia , Melfalan/administração & dosagem , Adulto , Contagem de Células Sanguíneas , Ciclofosfamida/uso terapêutico , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Feminino , Humanos , Masculino , Melanoma/tratamento farmacológico , Melanoma/mortalidade , Melanoma/secundário , Melfalan/efeitos adversos , Pessoa de Meia-Idade , Fatores de Tempo
12.
Gut ; 23(6): 465-74, 1982 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7042484

RESUMO

Liver dysfunction occurs after bone marrow transplantation but the relative importance of graft versus host disease and other factors, such as infection, radiation, and drugs, has not been clearly established. We have studied liver status before and after bone marrow transplantation in 43 consecutive patients and have related this to survival and factors that are recognised to cause liver injury. Minor abnormalities of liver tests occurred in 21% of patients before grafting but this did not influence survival or the development of liver disease after transplantation. During the first 50 days after grafting, 83% of patients had abnormal liver tests which were more severe in patients who subsequently died. Alanine transaminase was significantly higher in non-survivors and appeared to predict survival early after transplantation. Only non-survivors developed clinical signs of liver disease. Severe liver disease was always associated with graft versus host disease and atypia of the small bile ducts was the most useful histological marker of hepatic involvement with this disease. Two of the patients with hepatic graft versus host disease also has hepatic veno-occlusive disease and three fatalities had opportunistic infection of the liver, although, in the latter, death was not due primarily to liver dysfunction. Previous hepatitis and androgen therapy could not be implicated as important causes of hepatic damage but chemotherapy for acute leukaemia and conditioning regimens for bone marrow transplantation appear to be the most important factors in the development of hepatic veno-occlusive disease.


Assuntos
Transplante de Medula Óssea , Reação Enxerto-Hospedeiro , Hepatopatias/etiologia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Fígado/patologia , Fígado/fisiopatologia , Hepatopatias/patologia , Hepatopatias/fisiopatologia , Masculino , Complicações Pós-Operatórias/etiologia , Prognóstico
13.
Gut ; 23(4): 304-9, 1982 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7076007

RESUMO

Amino acid absorption from a peptide-containing protein hydrolysate and an equivalent amino acid mixture over a range of concentrations of the two--such as is thought to be found in the normal intestine after a meal--has been studied using a jejunal perfusion technique in man. The relative rates of amino acid absorption from the protein hydrolysate and amino acid mixture varied markedly with concentration, demonstrating that the global hypothesis that peptides confer an advantage in amino acid absorption in vivo is too simple. There is a highly significant correlation between amino acid absorption and the concentrations of amino acid in the perfusate, whether this contained amino acid or protein hydrolysate, suggesting that, under these experimental conditions at least, the presence of distinct amino acid and peptide transport systems is relatively unimportant. Doubt is thus cast upon suggestions derived from previous intestinal perfusion experiments that intact peptide transport may be nutritionally significant in man.


Assuntos
Absorção Intestinal , Jejuno/metabolismo , Peptídeos/metabolismo , Hidrolisados de Proteína/metabolismo , Adulto , Aminoácidos/administração & dosagem , Aminoácidos/metabolismo , Humanos , Lactalbumina/metabolismo , Perfusão , Hidrolisados de Proteína/administração & dosagem
14.
Ann Nutr Metab ; 26(6): 337-52, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-6756278

RESUMO

An in vivo intestinal perfusion technique has been used to investigate the characteristics of di- and tripeptides absorption in man. The results suggest that the model peptides studied were absorbed by a transport system separate to those responsible for mediating absorption of free amino acids. Two modes of intestinal uptake have been identified, namely transport of unhydrolysed peptides and transport of free amino acid residues liberated from the peptides by the action of brush border peptidases. A consistent finding was that amino acid residues were absorbed more rapidly from di- and tripeptides than from free amino acids. When amino acid uptake from four partial enzymic hydrolysates of protein was investigated, the 'kinetic advantage' conferred by peptides on amino acid uptake was found to be a generalized and concentration-dependent phenomenon. As later test meal studies showed that orally administered peptide mixtures were assimilated at least as rapidly as free amino acid mixtures, serious consideration could be given to using the less hypertonic and more palatable oligopeptide-based nitrogen sources in chemically defined elemental diets.


Assuntos
Aminoácidos/metabolismo , Intestinos/fisiologia , Oligopeptídeos/metabolismo , Aminoácidos/administração & dosagem , Animais , Transporte Biológico , Cistinúria/metabolismo , Dipeptídeos/metabolismo , Humanos , Absorção Intestinal , Intestino Delgado , Intubação , Cinética , Peptídeo Hidrolases , Hidrolisados de Proteína/administração & dosagem , Ratos
15.
J Virol ; 39(3): 816-22, 1981 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6169841

RESUMO

The infectivity of most rotaviruses is enhanced by treatment with trypsin. We studied the mechanism of enhancement of examining the effect of trypsin on rotavirus infectivity, aggregation, early interactions with host cells, and structure. The results indicated that trypsin does not increase levels of infectious virus by dispersion of aggregates or affect the efficiency or rate of attachment of virus to cells. A fraction of virus that was not infections without trypsin treatment was found to attach to cells, but did not initiate antigen synthesis. When cells were infected with labeled, purified virus, increased levels of uncoated particles were found in cells infected with trypsin-treated virus. Infection of cells with trypsin-treated virus also led to greater levels of RNA synthesis early in the infection. The results suggest that trypsin converts a noninfectious fraction of virus into infectious virus by allowing this fraction to uncoat in the infected cell. Trypsin was found to cleave an 88,000-dalton structural polypeptide of bovine rotavirus generating 67,000- and 20,000-dalton cleavage products.


Assuntos
Reoviridae/crescimento & desenvolvimento , Rotavirus/crescimento & desenvolvimento , Tripsina/farmacologia , Animais , Bovinos , Linhagem Celular , Macaca mulatta , RNA/biossíntese , Rotavirus/efeitos dos fármacos , Rotavirus/metabolismo , Proteínas Virais/metabolismo
16.
JPEN J Parenter Enteral Nutr ; 4(6): 548-53, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-6780707

RESUMO

Previous studies have shown that amino acid (AA) residues are absorbed more rapidly from di- tripeptides than from free AA. In the present study, an intestinal perfusion technique has been used in normal human subjects to compare absorption of AA residues and total alpha-amino nitrogen (N) from 4 partial enzymic hydrolysates of protein (50--80% of the N contents present as small peptides) and their respective equimolar free AA mixtures. alpha-Amino N absorption was greater from 2 casein hydrolytes and a lactalbumin hydrolysate than from the respective free AA mixtures but similar to that from a fish protein hydrolysate and its AA mixture. The considerable variation in absorption of individual AA residues from the AA mixtures was much reduced when the protein hydrolysates were perfused, as a number of AA which were poorly absorbed from the AA mixtures were absorbed to a greater extent from the protein hydrolysates. The casein and lactalbumin hydrolysates had a stimulatory effect on jejunal absorption of water and electrolytes. In contrast, the fish protein hydrolysate appeared to cause a mean net secretion of fluid and electrolytes. The findings indicate that when absorption is limited by diminished luminal hydrolysis or absorptive capacity, serious consideration might be given to using partial enzymic hydrolysates of whole protein rather than free AA mixtures as the N source in "elemental" diets. Care should be taken, however, in ensuring that the preparation of choice does not promote a net secretion of fluid and electrolytes for such a property could have a deleterious effect in the clinical setting.


Assuntos
Alimentos Formulados , Jejuno/metabolismo , Nutrição Parenteral Total , Nutrição Parenteral , Peptídeos/metabolismo , Hidrolisados de Proteína/metabolismo , Adulto , Aminoácidos/metabolismo , Animais , Caseínas/metabolismo , Produtos Pesqueiros , Peixes , Humanos , Absorção Intestinal , Lactalbumina/metabolismo , Masculino , Nitrogênio/metabolismo , Valor Nutritivo , Papaína/metabolismo , Perfusão , Tripsina/metabolismo
17.
Br Med J ; 2(6194): 822-4, 1979 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-509112

RESUMO

A method is described of estimating retrograde spread through the colon of a 10% hydrocortisone acetate foam by labelling the foam with technetium-99m sulphur colloid and observing spread after intrarectal administration by serial gamma-camera pictures. The recommended 51 ml dose of foam reached the mid-sigmoid colon in all of the nine patients who had active ulcerative colitis. Furthermore, in seven the foam reached the proximal sigmoid colon. Foam spread less extensively in five patients with quiescent disease than in those with active disease. Increasing the volume of enema to 50 ml did not improve retrograde spread through the colon. These results suggest that 10% hydrocortisone foam may be useful in treating patients with distal ulcerative colitis that is not necessarily limited to the rectum.


Assuntos
Anti-Inflamatórios/metabolismo , Colite Ulcerativa/metabolismo , Administração Tópica , Adulto , Idoso , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/uso terapêutico , Colite Ulcerativa/diagnóstico por imagem , Colite Ulcerativa/tratamento farmacológico , Colo Sigmoide/diagnóstico por imagem , Enema , Feminino , Raios gama , Humanos , Hidrocortisona , Masculino , Pessoa de Meia-Idade , Cintilografia , Reto
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