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2.
Intern Med J ; 46(1): 79-85, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26386271

RESUMO

BACKGROUND: Demand for inpatient beds is increasing whilst supply is diminishing. General medical services are feeling this demand as the ageing population presents more patients with undifferentiated illness traditionally cared for by this service. Redesign efforts need to focus on improving the quality and speed of decision-making to utilise resources efficiently. AIMS: The aim of this study was to improve patient flow through general medical services by undertaking a comprehensive redesign process targeting each stage of the patient journey. METHODS: We utilised a rapid improvement event to identify waste and design a new model of care (MOC) that eliminated as much waste as possible. The model had three main elements: (i) ward-based teams; (ii) 7-day per week standard work; and (iii) pull systems to operate for all transfers and referrals. Here, we analyse the first 12 months of the new MOC with regard to key outcomes: length of stay, occupancy, weekend discharges, clinical incidents and Medical Emergency Team (MET) calls, emergency department length of stay and National Emergency Access Target (NEAT) performance and elective surgical throughput. RESULTS: The new MOC resulted in a 0.88-day reduction in length of stay. This resulted in reduced general medical bed occupancy of 19 beds. Weekend discharges improved by 54.6%. There were no significant increases in serious clinical incidents or MET calls. Emergency department admitted NEAT performance improved also. CONCLUSION: Redesign of the general medicine model of care eliminating waste has resulted in a significant improvement in patient flow and reduced length of stay without compromising quality of care.


Assuntos
Serviços Médicos de Emergência/métodos , Serviço Hospitalar de Emergência , Medicina Geral/métodos , Tempo de Internação , Equipe de Assistência ao Paciente , Estudos de Coortes , Serviços Médicos de Emergência/tendências , Serviço Hospitalar de Emergência/tendências , Medicina Geral/tendências , Humanos , Tempo de Internação/tendências , Equipe de Assistência ao Paciente/tendências , Fatores de Tempo , Resultado do Tratamento
3.
Intern Med J ; 46(2): 141-8, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25732203

RESUMO

Androgen deprivation therapy (ADT) is a standard systemic treatment for men with prostate cancer. Men on ADT may be elderly and have comorbidities that are exacerbated by ADT, such as cardiovascular disease, diabetes, obesity, sedentary lifestyle and osteoporosis. Studies on managing the impacts of ADT have focused on men with non-metastatic disease, where ADT is given for a limited duration. However, some men with advanced or metastatic prostate cancer will achieve long-term survival with palliative ADT and therefore also risk morbidity from prolonged ADT. Furthermore, ADT is continued during the use of other survival-prolonging therapies for men with advanced disease, and there is a general trend to use ADT earlier in the disease course. As survival improves, management of the metabolic effects of ADT becomes important for maintaining both quality and quantity of life. This review will outline the current data, offer perspectives for management of ADT complications in men with advanced prostate cancer and discuss avenues for further research.


Assuntos
Androgênios/deficiência , Antineoplásicos Hormonais/uso terapêutico , Gerenciamento Clínico , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo , Antineoplásicos Hormonais/farmacologia , Humanos , Masculino , Doenças Metabólicas/tratamento farmacológico , Doenças Metabólicas/metabolismo
4.
Intern Med J ; 44(8): 727-34, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24862939

RESUMO

BACKGROUND: The majority of differentiated thyroid cancers are characterised by one of several point mutations or gene rearrangements. Limited data are available on the prevalence and clinical correlations of these mutations in the Australian population. AIMS: The aim of the present study was to characterise the mutation profile of differentiated thyroid tumours in the local population. METHODS: The study involved 148 patients with differentiated thyroid cancer. The following tumours were examined: 109 papillary carcinomas (PTC), 27 follicular carcinomas (FC) and 12 Hurthle cell carcinomas (HCC). Polymerase chain reaction (PCR) was performed for BRAF and RAS mutations (RNA and DNA) as well as for RET/PTC rearrangements and PAX8-PPARγ translocations (RNA). Clinicopathological parameters and outcome data were analysed according to BRAFV600E status in PTC and RAS mutation status in FC. RESULTS: BRAFV600E was identified in 74/109 (68%) PTC. BRAFV600E was not significantly correlated with clinicopathological features of aggressive disease. At a median follow up of 48 months, there was no significant difference between BRAFV600E and wild-type BRAF PTC with respect to the rates of nodal recurrence, distant metastases or disease-specific death. In FC, RAS mutations (five NRAS and three HRAS) were present in 8/27 (30%) tumours. RAS mutation was significantly associated with widely invasive histology (P = 0.01) and distant metastases (P = 0.01) on follow up. CONCLUSION: In the present study, BRAF mutation was not associated with negative prognostic indicators or adverse outcomes in PTC. RAS mutation was positively correlated with aggressive features in FC suggesting potential prognostic utility, although confirmation is required from larger studies.


Assuntos
DNA de Neoplasias/genética , Mutação , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias da Glândula Tireoide/genética , População Urbana , Análise Mutacional de DNA , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prognóstico , Proteínas Proto-Oncogênicas B-raf/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/epidemiologia , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia , Vitória/epidemiologia
5.
Health Technol Assess ; 13 Suppl 1: 49-54, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19567214

RESUMO

This paper presents a summary of the evidence review group (ERG) report into the clinical and cost-effectiveness of cetuximab plus radiotherapy for the treatment of locally advanced squamous cell carcinoma of the head and neck (LA SCCHN) considered inappropriate for chemoradiotherapy but appropriate for radiotherapy, based upon the evidence submission from Merck Pharmaceuticals to the National Institute for Health and Clinical Excellence (NICE) as part of the single technology appraisal (STA) process. The manufacturer's submission was generally of good quality and was an accurate representation of the original reference data. One good-quality randomised controlled trial comparing radiotherapy plus cetuximab with radiotherapy alone in patients with stage III or IV non-metastatic LA SCCHN was included, demonstrating that the duration of locoregional control was significantly longer with radiotherapy plus cetuximab than with radiotherapy alone; also, overall and progression-free survival were significantly longer and the overall response rate was significantly better with the combination therapy. Cetuximab did not exacerbate the common toxic effects associated with radiotherapy of the head and neck. No supporting evidence for these findings are available. The patient population in the trial included a high proportion of patients who would be expected to be suitable for chemoradiotherapy and therefore does not match the population described in the submission's decision problem. Also, the radiotherapy regimens used in the trial are not typical of current UK practice. The ERG considered the manufacturer's economic evaluation to comprise the only relevant evidence to consider for the purposes of this STA. The economic model was considered appropriate for the decision problem. The results suggested that cetuximab plus radiotherapy was cost-effective compared with radiotherapy alone under a broad range of different assumptions on the basis of a cost-effectiveness threshold of 20,000 pounds. In the base case the incremental cost-effectiveness ratio of cetuximab plus radiotherapy compared with radiotherapy alone in the treatment of patients with LA SCCHN was 6390 pounds per additional QALY. Simple sensitivity analyses to examine the robustness of the results were undertaken, suggesting that areas of uncertainty that emerged in the modelling are unlikely to have a material effect on the conclusions. The guidance issued by NICE in May 2007 as a result of the STA states that cetuximab in combination with radiotherapy is not recommended for patients with LA SCCHN.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Neoplasias de Células Escamosas/tratamento farmacológico , Neoplasias de Células Escamosas/radioterapia , Anticorpos Monoclonais/economia , Anticorpos Monoclonais Humanizados , Antineoplásicos/economia , Cetuximab , Terapia Combinada , Análise Custo-Benefício , Neoplasias de Cabeça e Pescoço/economia , Humanos , Neoplasias de Células Escamosas/economia , Anos de Vida Ajustados por Qualidade de Vida , Análise de Sobrevida , Avaliação da Tecnologia Biomédica
6.
Intern Med J ; 37(10): 674-9, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17894764

RESUMO

BACKGROUND: The aim of this study was to examine current fracture prevention strategies through the recognition, investigation and treatment of osteoporosis in patients presenting to acute hospitals with minimal-trauma fracture. METHODS: A retrospective audit using a standardized database was conducted in 16 Australian hospitals. This involved 1829 cases of minimal-trauma fracture initially presenting to hospital emergency departments during 2003-2005. Cases of minimal-trauma fracture were retrospectively identified using diagnosis-related group fracture codes and case record review at each site. Relevant data were entered into a standardized database and analysed centrally and independently. Risk factors for osteoporosis, investigations, interventions and discharge follow up were recorded. RESULTS: The percentage of minimal-trauma fracture patients who underwent investigation or initiated therapy designed to prevent subsequent minimal-trauma fracture was obtained. Less than 13% of patients presenting to hospital with minimal-trauma fractures had risk factors for fracture identified. Ten per cent were appropriately investigated, 12% were commenced on calcium and 12% on vitamin D. Eight per cent started bisphosphonates and 1% selective oestrogens receptor modulators in the acute setting. CONCLUSION: Most patients presenting to Australian hospitals with minimal-trauma fracture are neither investigated nor treated for osteoporosis. As this group is at high risk of subsequent fracture, this is a missed opportunity to reduce fracture burden.


Assuntos
Fraturas Ósseas/epidemiologia , Fraturas Ósseas/prevenção & controle , Hospitais , Idoso , Idoso de 80 Anos ou mais , Austrália/epidemiologia , Cálcio da Dieta/uso terapêutico , Comissão Para Atividades Profissionais e Hospitalares/tendências , Feminino , Seguimentos , Fraturas Ósseas/etiologia , Hospitais/tendências , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/complicações , Osteoporose/epidemiologia , Osteoporose/terapia , Estudos Retrospectivos , Resultado do Tratamento
7.
Calcif Tissue Int ; 79(3): 138-44, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16969592

RESUMO

Beta-thalassaemia major is associated with low bone mass and fractures. We conducted a 2 year randomized controlled trial of zoledronic acid 4 mg administered intravenously every 3 months or placebo in the treatment of beta-thalassaemia-associated osteopenla. We recruited 23 subjects from 2 university hospitals with a T score of less than -1.0 at either the lumbar spine or hip, and 23 subjects completed the study (17 M, 6 F). Treatment groups did not differ significantly with respect to bone mineral density (BMD), age, height, weight and body mass index (BMI) at baseline. BMD was assessed at baseline, 12 months and 24 months by dual-energy X-ray absorptiometry (DXA) at the lumbar spine, femoral reek, total hip and total body. After two years average lumbar spine BMD was 8.9% greater (95%CI 2.3-15.5%, P = 0.011), average femoral neck BMD was 9.1% greater (95%CI 5.5-12.7%, P < 0.0001), average total hip BMD was 9.6% greater (95%CI 6.5-12.6%, P < 0.0001) and average total body BMD was 4.7% greater (95%CI 2.7-6.8%, P < 0.0001) in the treated group compared to placebo. The absolute change in BMD from baseline to 2 years and the annualized rate of change of BMD was significantly greater in treated patients at all four sites. Age, gender, height, weight and BMI did not interact with the effect of treatment and so unadjusted data was used. The serum total ALP decreased 45% by 12 months (P = 0.004) and urinary deoxypyridinoline/creatinine ratio decreased 47% by 3 months (NS). We conclude that zoledronic acid (4 mg i.v. 3 monthly) suppresses bone turnover and increases BMD in beta-thalassaemia-associated osteopenia.


Assuntos
Conservadores da Densidade Óssea/administração & dosagem , Densidade Óssea/efeitos dos fármacos , Doenças Ósseas Metabólicas/prevenção & controle , Difosfonatos/administração & dosagem , Imidazóis/administração & dosagem , Talassemia beta/complicações , Adolescente , Adulto , Fosfatase Alcalina/sangue , Fosfatase Alcalina/efeitos dos fármacos , Doenças Ósseas Metabólicas/etiologia , Método Duplo-Cego , Feminino , Humanos , Masculino , Ácido Zoledrônico
9.
Am J Physiol Endocrinol Metab ; 281(5): E991-7, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11595655

RESUMO

The rate of glucose turnover (R(a)) and gluconeogenesis (GNG) via pyruvate were quantified in seven full-term healthy babies between 24 and 48 h after birth and in twelve low-birth-weight infants on days 3 and 4 by use of [(13)C(6)]glucose and (2)H(2)O. The preterm babies were receiving parenteral alimentation of either glucose or glucose plus amino acid with or without lipids. The contribution of GNG to glucose production was measured by the appearance of (2)H on C-6 of glucose. Glucose R(a) in full-term babies was 30 +/- 1.7 (SD) micromol. kg(-1). min(-1). GNG via pyruvate contributed approximately 31% to glucose R(a). In preterm babies, the contribution of GNG to endogenous glucose R(a) was variable (range 6-60%). The highest contribution was in infants receiving low rates of exogenous glucose infusion. In an additional group of infants of normal and diabetic mothers, lactate turnover and its incorporation into glucose were measured within 4-24 h of birth by use of [(13)C(3)]lactate tracer. The rate of lactate turnover was 38 micromol. kg(-1). min(-1), and lactate C, not corrected for loss of tracer in the tricarboxylic acid cycle, contributed approximately 18% to glucose C. Lactate and glucose kinetics were similar in infants that were small for their gestational age and in normal infants or infants of diabetic mothers. These data show that gluconeogenesis is evident soon after birth in the newborn infant and that, even after a brief fast (5 h), GNG via pyruvate makes a significant contribution to glucose production in healthy full-term infants. These data may have important implications for the nutritional support of the healthy and sick newborn infant.


Assuntos
Gluconeogênese , Aminoácidos/administração & dosagem , Glicemia/metabolismo , Água Corporal/metabolismo , Isótopos de Carbono , Deutério , Diabetes Mellitus Tipo 1/sangue , Feminino , Glucose/administração & dosagem , Glucose/metabolismo , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Recém-Nascido Prematuro , Recém-Nascido Pequeno para a Idade Gestacional , Ácido Láctico/sangue , Nutrição Parenteral , Gravidez , Gravidez em Diabéticas/sangue , Ácido Pirúvico/metabolismo
11.
J Clin Endocrinol Metab ; 81(4): 1557-62, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8636367

RESUMO

Dizygotic twinning is familial, suggesting that there may be an inherited abnormality of the control of ovulation that predisposes to double ovulation and, therefore, dizygotic twins. The present study examines 17 mothers of dizygotic twins (MODZT) and 8 control mothers of singletons by daily blood sampling throughout an entire menstrual cycle. Blood samples were assayed for LH, FSH, estradiol, progesterone, and inhibin. The process of follicular development was followed by transvaginal ultrasound. The pituitary LH response to iv GnRH was also assessed. Three of the 16 MODZT double ovulated during the study compared to none of the 8 control mothers (P < 0.05). The number of small follicles (<6 mm) declined significantly in control women at midcycle, but not in MODZT. There was no significant difference in serum FSH, LH, estradiol, or inhibin levels between the 2 groups at any stage of the menstrual cycle. During the follicular phase, serum progesterone levels were significantly higher in MODZT. The response to GnRH stimulation was not different between MODZT and controls. In conclusion, this study demonstrates an increased tendency to double ovulate in MODZT that may be due to a reduced rate of atresia in advanced follicles. Furthermore, the elevated progesterone levels in MODZT during the follicular phase suggest altered intrafollicular steroidogenesis that is independent of gonadotropins.


Assuntos
Hormônio Luteinizante/metabolismo , Ciclo Menstrual/fisiologia , Mães , Folículo Ovariano/fisiologia , Ovulação , Gêmeos Dizigóticos , Adulto , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Hormônio Liberador de Gonadotropina , Humanos , Inibinas/sangue , Hormônio Luteinizante/sangue , Hormônio Luteinizante/urina , Folículo Ovariano/diagnóstico por imagem , Paridade , Hipófise/efeitos dos fármacos , Hipófise/metabolismo , Progesterona/sangue , Ultrassonografia
12.
Maturitas ; 20(2-3): 199-208, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7715473

RESUMO

In order to evaluate the role of single photon absorptiometry (SPA) in the prediction of osteoporotic fracture risk, 1935 women, referred for measurement of forearm mineral density (FMD) at the distal radial site, were studied by questionnaire in a cross-sectional design. There was no significant decline in FMD until the age of 47, after which there was a linear decline with age of about 1.2% per year. There was no relationship between age and FMD, or forearm mineral content (FMC), in premenopausal women. There was a fall in FMD with the number of years since menopause, after correcting for the effects of age, of approximately 0.5% per year. Body weight was positively correlated with FMC in postmenopausal women. The duration of exposure to hormone replacement therapy (HRT) was positively correlated with FMD, and the magnitude of this effect was reduced the longer the delay between the onset of the menopause and the commencement of HRT. There was no significant association of FMD with calcium intake, weight-bearing exercise, tobacco or alcohol consumption, or family history of osteoporosis. FMD was significantly lower in postmenopausal women who reported fractures after the age of 25, after correcting for age and years postmenopause. In conclusion, a low FMD is predictive of a past history of fractures and may therefore be capable of predicting future fracture risk.


Assuntos
Densidade Óssea/fisiologia , Fraturas Espontâneas/fisiopatologia , Osteoporose Pós-Menopausa/fisiopatologia , Absorciometria de Fóton , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antropometria , Densidade Óssea/efeitos dos fármacos , Terapia de Reposição de Estrogênios , Estrogênios/fisiologia , Exercício Físico/fisiologia , Feminino , Fraturas Espontâneas/prevenção & controle , Humanos , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/prevenção & controle , Rádio (Anatomia)/efeitos dos fármacos , Rádio (Anatomia)/fisiopatologia , Fatores de Risco
13.
Clin Endocrinol (Oxf) ; 41(4): 453-61, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7525122

RESUMO

OBJECTIVE: Follistatin (FS/FSH-suppressing protein/activin-binding protein) is a single-chain glycoprotein, structurally distinct from inhibin, that has been shown to have inhibin-like activity in suppressing FSH secretion both in vivo and in vitro. The aim of these studies was to develop and validate a radioimmunoassay (RIA) for FS in human serum, and to describe the physiological variations of serum FS in humans. PATIENTS: Serum was collected from normal men, and normal women in the follicular and luteal phases of the menstrual cycle. Clinical samples were also collected from male patients with hypogonadism, post-menopausal women and pregnant women in the first, second and third trimesters. MEASUREMENTS: A RIA for FS in human serum was developed using antisera raised against purified bovine FS and using bovine FS as tracer and standard. Serial dilutions of serum were non-parallel to purified bovine FS standard in the RIA. The addition of sodium dodecyl sulphate (SDS 0.05%) to the assay buffer resolved the non-parallelism suggesting that the interference of serum in the RIA was an assay matrix effect. To characterize the serum FS immunoactivity further, serum was fractionated by gel filtration on Sephadex G-100. At neutral pH, FS immunoactivity eluted as a major peak in the molecular weight range > 200 kDa. In 0.1 M HCl, a second peak of FS immunoactivity eluted in the molecular weight range 30-60 kDa consistent with the known sizes of FS. This suggested that FS was dissociating from a larger complex. Fractions taken from the low molecular weight region diluted in parallel with bovine FS in contrast with fractions from the high molecular weight region which were non-parallel. It is concluded that the non-parallelism of human serum in the FS RIA is due to the binding of serum FS to an unknown high molecular weight factor. This interference is eliminated by the inclusion of 0.05% SDS in the assay buffer. The RIA in 0.05% SDS has been applied to the description of the normal and pathophysiological variations of FS in human serum. RESULTS: There were no significant differences between FS levels in serum from hypogonadal men, normal women in the follicular phase of the menstrual cycle, post-menopausal women and pregnant women from the first, second and third trimesters. FS levels in serum of women in the luteal phase of the menstrual cycle were significantly lower than all other groups. FS levels in normal men were significantly higher than those in both luteal phase women and women in the first trimester of pregnancy (P < 0.05). CONCLUSIONS: These findings argue against a role for circulating follistatin in the control of gonadotrophin secretion and suggest that the gonads and/or conceptus are not the primary source of follistatin immunoactivity in serum. The lower follistatin levels in the luteal phase of the menstrual cycle remain unexplained.


Assuntos
Glicoproteínas/sangue , Cromatografia de Afinidade , Cromatografia em Gel , Feminino , Fase Folicular/sangue , Folistatina , Humanos , Hipogonadismo/sangue , Fase Luteal/sangue , Masculino , Pós-Menopausa/sangue , Gravidez , Primeiro Trimestre da Gravidez , Radioimunoensaio , Reprodutibilidade dos Testes , alfa-Macroglobulinas/análise
14.
Metabolism ; 37(2): 152-8, 1988 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3123875

RESUMO

In order to quantify the glucose-alanine relationship in normal human pregnancy, the turnover rates of alanine and the incorporation of alanine carbon into glucose were quantified in 15 pregnant women during the last 4 weeks of gestation following a ten-hour fast. Eight nonpregnant women of similar age group were studied as controls. L-[2,3-13C2]Alanine and D[6,6-2H2]glucose were infused as tracers. The 13C enrichment of alanine, lactate, and glucose and the deuterium enrichment of glucose were measured by gas chromatography-mass spectrometry. In five pregnant and five nonpregnant women, the contribution of alanine carbon to expired CO2 directly and via glucose was estimated by combining indirect respiratory calorimetry with the tracer infusions. The alanine turnover rates in the pregnant and nonpregnant women were similar (pregnant, 4.43 +/- 0.82 mumol/kg x min; nonpregnant, 4.11 +/- 1.08 mumol/kg x min, mean +/- SD). However, the fraction of alanine incorporated into glucose was significantly lower during pregnancy (23.5 +/- 8.3% v 30.8 +/- 8.2%, P less than .04). In pregnant women, 20% of lactate pool was derived from alanine as compared with 28% in nonpregnant subjects (P less than .02). Twenty-four percent of alanine turnover was converted to CO2 in both pregnant and nonpregnant women. The plasma insulin concentration was increased significantly during pregnancy (P less than .05). These data suggest that gluconeogenesis from alanine is attenuated during pregnancy. This decrease in gluconeogenesis is not the result of decreased alanine flux, but due to intrinsic intrahepatic mechanism such as decreased deamination of alanine mediated by the predominant insulin effect or a decreased hepatic uptake of alanine.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Alanina/metabolismo , Glucose/metabolismo , Gravidez/metabolismo , Adulto , Peso Corporal , Dióxido de Carbono/metabolismo , Feminino , Gluconeogênese , Hormônios/sangue , Humanos , Lactatos/metabolismo , Ácido Láctico
15.
Biol Neonate ; 47(3): 141-7, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3986252

RESUMO

In a previous study, we demonstrated the complete dependence of the human fetus on the mother for its glucose needs. As alanine is considered the major glucogenic amino acid synthesized endogenously and an important source of urea nitrogen, in the present study we examined whether the human fetus at term gestation can produce alanine. 5 normal pregnant women, undergoing elective cesarean section, were given a constant infusion of [2,3-13C2]alanine in trace quantities for a period of 4 h prior to and during surgery. Isotopic steady state was achieved in the maternal blood by 1.5 h and maintained through anesthesia and surgery. The 13C enrichment (mol% excess) of alanine was measured in the peripheral blood of the mother and in the simultaneously obtained umbilical arterial and venous blood at delivery. Even though the umbilical venous and arterial concentrations of alanine were similar, a 42% decrease in 13C enrichment of alanine occurred between umbilical vein and artery, 1.00 +/- 0.23 and 0.58 +/- 0.15%, respectively (mean +/- SD). These data suggest that the human fetus at term gestation following an overnight maternal fast produces alanine endogenously. This may serve to transfer nitrogen from fetal muscle to the liver for urea synthesis.


Assuntos
Alanina/biossíntese , Feto/metabolismo , Alanina/sangue , Glicemia/análise , Sangue Fetal/análise , Cromatografia Gasosa-Espectrometria de Massas , Idade Gestacional , Humanos , Lactatos/sangue
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