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1.
Ann R Coll Surg Engl ; 102(9): 693-696, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32538118

RESUMO

INTRODUCTION: The incidence of delayed gastric emptying (DGE) following oesophagogastrectomy with gastric conduit reconstruction is reported to be between 1.7% and 50%. This variation is due to differing practices of intraoperative pylorus drainage procedures, which increase the risk of postoperative biliary reflux and dumping syndrome, resulting in significant morbidity. The aim of our study was to establish rates of DGE in people undergoing oesophagogastrectomy without routine intraoperative drainage procedures, and to evaluate outcomes of postoperative endoscopically administered Botulinum toxin into the pylorus (EBP) for people with DGE resistant to systemic pharmacological treatment. METHODS: All patients undergoing oesophagogastrectomy between 1 January 2016 and 31 March 2018 at our unit were included. No intraoperative pyloric drainage procedures were performed, and DGE resistant to systemic pharmacotherapy was managed with EBP. RESULTS: Ninety-seven patients were included. Postoperatively, 29 patients (30%) were diagnosed with DGE resistant to pharmacotherapy. Of these, 16 (16.5%) were diagnosed within 30 days of surgery. The median pre-procedure nasogastric tube aspirate was 780ml; following EBP, this fell to 125ml (p<0.001). Median delay from surgery to EBP in this cohort was 13 days (IQR 7-16 days). Six patients required a second course of EBP, with 100% successful resolution of DGE before discharge. There were no procedural complications. CONCLUSIONS: This is the largest series of patients without routine intraoperative drainage procedures. Only 30% of patients developed DGE resistant to pharmacotherapy, which was managed safely with EBP in the postoperative period, thus minimising the risk of biliary reflux in people who would otherwise be at risk following prophylactic pylorus drainage procedures.


Assuntos
Toxinas Botulínicas Tipo A/uso terapêutico , Esofagectomia/efeitos adversos , Gastrectomia/efeitos adversos , Gastroparesia/tratamento farmacológico , Gastroscopia , Piloro/efeitos dos fármacos , Toxinas Botulínicas Tipo A/administração & dosagem , Neoplasias Esofágicas/cirurgia , Esofagectomia/métodos , Feminino , Gastrectomia/métodos , Gastroparesia/etiologia , Gastroscopia/métodos , Humanos , Masculino , Piloro/fisiopatologia , Neoplasias Gástricas/cirurgia
2.
Sci Rep ; 8(1): 2661, 2018 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-29422513

RESUMO

Conservation concerns exist for many sharks but robust estimates of abundance are often lacking. Improving population status is a performance measure for species under conservation or recovery plans, yet the lack of data permitting estimation of population size means the efficacy of management actions can be difficult to assess, and achieving the goal of removing species from conservation listing challenging. For potentially dangerous species, like the white shark, balancing conservation and public safety demands is politically and socially complex, often leading to vigorous debate about their population status. This increases the need for robust information to inform policy decisions. We developed a novel method for estimating the total abundance of white sharks in eastern Australia and New Zealand using the genetic-relatedness of juveniles and applying a close-kin mark-recapture framework and demographic model. Estimated numbers of adults are small (ca. 280-650), as is total population size (ca. 2,500-6,750). However, estimates of survival probability are high for adults (over 90%), and fairly high for juveniles (around 73%). This represents the first direct estimate of total white shark abundance and survival calculated from data across both the spatial and temporal life-history of the animal and provides a pathway to estimate population trend.


Assuntos
Tubarões/genética , Animais , Austrália , Conservação dos Recursos Naturais/métodos , Demografia , Ecossistema , Genética Populacional , Nova Zelândia , Densidade Demográfica
3.
Ann R Coll Surg Engl ; 99(7): 515-523, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28853597

RESUMO

Introduction The incidence of gastro-oesophageal reflux disease and obesity has increased significantly in recent years. The number of antireflux procedures being carried out on people with a higher body mass index (BMI) has been rising. Evidence is conflicting for outcomes of antireflux surgery in obese patients in terms of its safety and efficacy. Given the contradictory reports, this meta-analysis was undertaken to establish the outcomes of antireflux surgery (ARS) in obese patients and its associated safety. Methods A systematic electronic search was conducted using the PubMed, MEDLINE®, Ovid®, Cochrane Library and Google Scholar™ databases to identify studies that analysed the effect of BMI on the outcomes of ARS. A meta-analysis was performed using the random effects model. The intraoperative and postoperative outcomes that were examined included operative time, conversion to an open procedure, mean length of hospital stay, recurrence of acid reflux requiring reoperation and wrap migration. Results A total of 3,772 patients were included in 13 studies. There was no significant difference in procedure conversion rate, recurrence of reflux requiring reoperation or wrap migration between obese and non-obese patients. However, both the mean operative time and mean length of stay were longer for obese patients. Conclusions ARS in obese patients with gastro-oesophageal reflux disease is safe and outcomes are comparable with those in patients with a BMI in the normal range. A high BMI should therefore not be a deterrent to considering ARS for appropriate patients.


Assuntos
Fundoplicatura , Refluxo Gastroesofágico/cirurgia , Obesidade/complicações , Fundoplicatura/efeitos adversos , Refluxo Gastroesofágico/etiologia , Humanos , Laparoscopia/efeitos adversos , Obesidade/cirurgia , Resultado do Tratamento
4.
Sci Rep ; 5: 16916, 2015 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-26593698

RESUMO

Tropical tuna fisheries are central to food security and economic development of many regions of the world. Contemporary population assessment and management generally assume these fisheries exploit a single mixed spawning population, within ocean basins. To date population genetics has lacked the required power to conclusively test this assumption. Here we demonstrate heterogeneous population structure among yellowfin tuna sampled at three locations across the Pacific Ocean (western, central, and eastern) via analysis of double digest restriction-site associated DNA using Next Generation Sequencing technology. The differences among locations are such that individuals sampled from one of the three regions examined can be assigned with close to 100% accuracy demonstrating the power of this approach for providing practical markers for fishery independent verification of catch provenance in a way not achieved by previous techniques. Given these results, an extended pan-tropical survey of yellowfin tuna using this approach will not only help combat the largest threat to sustainable fisheries (i.e. illegal, unreported, and unregulated fishing) but will also provide a basis to transform current monitoring, assessment, and management approaches for this globally significant species.


Assuntos
Conservação dos Recursos Naturais , Genética Populacional , Genótipo , Polimorfismo de Nucleotídeo Único , Atum/genética , Animais , Ecossistema , Feminino , Pesqueiros/economia , Pesqueiros/ética , Técnicas de Genotipagem , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Oceano Pacífico , Atum/classificação
5.
Ceylon Med J ; 58(2): 82-3, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23817940

RESUMO

The Department of Family Medicine, University of Kelaniya conducted a health camp in Puthukudiyiruppu in March 2011. Height and weight measurements were carried out and data of 303 participants were analysed. The rate of stunting among children below six years in this population was 62% compared to 19.3% nationally. Thirty four percent of children and adolescents (6-18yrs) were underweight and 21.4% of adults had a BMI less than 18.5kg/m2.


Assuntos
Estatura , Transtornos do Crescimento , Humanos , Magreza/epidemiologia
7.
J Forensic Leg Med ; 19(5): 297-301, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22687773

RESUMO

We report an autopsy case of a 42-year-old woman who, when discovered, had been dead in her apartment for approximately 1 week under circumstances involving treachery, assault and possible drug overdose. This case is unique as it involved two autopsies of the deceased by two different medical examiners who reached opposing conclusions. The first autopsy was performed about 10 days after death. The second autopsy was performed after an exhumation approximately 2 years after burial. Evidence collected at the crime scene included blood samples from which DNA was extracted and analysed, fingerprints and clothing containing dried body fluids. The conclusion of the first autopsy was accidental death due to cocaine toxicity; the conclusion of the second autopsy was death due to homicide given the totality of evidence. Suspects 1 and 2 were linked to the death of the victim by physical evidence and suspect 3 was linked by testimony. Suspect 1 received life in prison, and suspects 2 and 3 received 45 and 20 years in prison, respectively. This case indicates that cocaine toxicity is difficult to determine in putrefied tissue and that exhumations can be important in collecting forensic information. It further reveals that the combined findings of medical examiners, even though contradictory, are useful in determining the circumstances leading to death in criminal justice. Thus, this report demonstrates that such criminal circumstances require comparative forensic review and, in such cases, scientific conclusions can be difficult.


Assuntos
Exumação , Homicídio , Adulto , Manchas de Sangue , Cocaína/análise , Contusões/patologia , DNA/isolamento & purificação , Dermatoglifia , Feminino , Patologia Legal , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Lacerações/patologia , Entorpecentes/análise , Osso Nasal/lesões , Osso Nasal/patologia , Fraturas Orbitárias/patologia , Reação em Cadeia da Polimerase , Fraturas Cranianas/patologia
8.
QJM ; 103(12): 941-52, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20736182

RESUMO

AIM: To evaluate relationship between odour identification, taste threshold, dopamine transporter scan (DaTSCAN) and motor function in early Parkinson's disease (PD) and their diagnostic accuracy. METHODS: Seventy-three patients with early parkinsonism were evaluated by the Unified Parkinson's Disease Rating Scale (UPDRS), DaTSCAN, electrogustometry (EGM) threshold and University of Pennsylvania Smell Identification Test (UPSIT). Olfactory Event-Related potentials (OERP) were performed on 49 patients. At follow-up (mean 15.3 months), patients were diagnosed as 'PD' or 'non-PD'. DaTSCAN images were assessed visually and semi-quantitatively by QuantiSPECT. RESULTS: The sensitivity of UPSIT (86%) was not significantly different from that of the DaTSCAN (92%). UPSIT correlated moderately with DaTSCAN uptake (r = 0.44; P < 0.005) and UPDRS score (r = 0.43; P < 0.05) and weakly with symptom duration (r = 0.25; P < 0.05). In the PD group, OERP showed increased latency but no change in amplitude and no correlation with DaTSCAN. EGM thresholds were impaired in 22% of the PD group but they did not correlate with any other test parameters. DaTSCAN-UPSIT discordance was found in nine patients with PD, but neither was diagnostically superior. CONCLUSION: Our patients with early PD have a frequent and severe olfactory deficit that correlates with disease severity, symptom duration and DaTSCAN but not EGM. The sensitivities of UPSIT and DaTSCAN are high at 86% and 92%, respectively. Although DaTSCAN is superior for 'localization', UPSIT is considerably 'cheaper', and neither is disease specific. EGM threshold impairment in PD is independent of the smell deficit, and probably signifies advanced disease.


Assuntos
Proteínas da Membrana Plasmática de Transporte de Dopamina/farmacocinética , Doença de Parkinson/diagnóstico , Limiar Sensorial/fisiologia , Olfato/fisiologia , Paladar/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Potenciais Evocados/fisiologia , Feminino , Humanos , Radioisótopos do Iodo , Masculino , Pessoa de Meia-Idade , Nortropanos , Doença de Parkinson/fisiopatologia
9.
Surgeon ; 1(2): 114-7, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15573633

RESUMO

Ischaemic rectal stricture formation is a rare but documented complication of aortic aneurysm surgery. We report the first case of acute large bowel obstruction secondary to this rare complication.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Procedimentos Cirúrgicos Eletivos/efeitos adversos , Obstrução Intestinal/etiologia , Isquemia/etiologia , Doenças Retais/etiologia , Reto/irrigação sanguínea , Idoso , Humanos , Masculino
10.
J Agric Food Chem ; 49(6): 3051-7, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11410008

RESUMO

This study was undertaken to characterize the pectin from four citrus species and to determine their in vitro inhibitory activities on the binding of fibroblast growth factor (FGF) to the FGF receptor (FGFR). Pectin from various parts of lemon, grapefruit, tangerine, and orange were isolated and characterized. Tangerine had the highest pectin content among the four citrus species. Segment membrane contained as much as or more pectin than flavedo/albedo. Anhydrogalacturonic content was highest in pectin from segment membrane of tangerine and flavedo/albedo of grapefruit. Lemon pectin contained the highest methoxyl content (MC), and grapefruit contained the largest proportion of lower molecular weight (<10000 Da) pectin. Tangerine contained the highest neutral sugar in both flavedo/albedo and segment membrane. The interdependency of heparin on factor-receptor interaction provides a means for identifying new antagonists of growth factor activity and thus for treatment of various diseases. These results showed that pectin significantly inhibited the binding of FGF-1 to FGFR1 in the presence of 0.1 microg/mL heparin. The pectin from the segment membrane of lemon was the most potent inhibitor. The inhibition activity was significantly correlated with sugar content, MC, and size of pectin. Kinetic studies revealed a competitive nature of pectin inhibition with the heparin, a crucial component of the FGF signal transduction process. The observation that the heparin-dependent biological activity of FGF signal transduction is antagonized by citrus pectin should be further investigated for the use of these pectins as anti-growth factor agents for potential health benefits.


Assuntos
Citrus/química , Fatores de Crescimento de Fibroblastos/metabolismo , Pectinas/análise , Receptores de Fatores de Crescimento de Fibroblastos/antagonistas & inibidores , Fatores de Crescimento de Fibroblastos/química , Heparina/química , Heparina/metabolismo , Cinética , Peso Molecular , Pectinas/classificação , Transdução de Sinais
11.
Nucl Med Commun ; 22(5): 493-7, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11388569

RESUMO

In this study we examined the delivered activity of radiopharmaceuticals injected into patients and the various factors which lead to incomplete delivery. Four commonly used 99Tcm radiopharmaceuticals were included, namely pertechnetate, methylene diphosphonate (MDP), macro-aggregated albumin (MAA) and tetrofosmin. There was no appreciable residual activity after injection of pertechnetate and MDP other than that due to the dead space in syringes (0.06 ml, 4% of measured activity). However, there was considerable residual activity following an MAA injection. This was particularly dependent on the radiopharmaceutical residence time in the syringe prior to injection. If MAA was pre-dispensed there was up to 80% of activity remaining in the syringe following injection. We have shown that this activity is not bound and can be decreased by agitating the syringe prior to the injection. For tetrofosmin, the activity remaining in the syringe was shown to be mostly due to adsorption of the tetrofosmin onto the plastic syringe (up to 30% of the activity); in particular, onto the rubber plunger. The amount of binding probably depends on the formulation of the rubber plunger and the plastic barrel, which varies between manufacturers. Of the three commonly used syringe brands (Becton-Dickinson, Sherwood, and Braun syringes) the Braun syringes were shown to have the least binding (6%) and would be most suitable for tetrofosmin injection. We recommend the use of Braun syringes for tetrofosmin. We also recommend that pre-dispensed MAA injections should be gently agitated before injection into the patient. No special precautions are necessary for pertechnetate or MDP injections.


Assuntos
Compostos Radiofarmacêuticos/administração & dosagem , Compostos Radiofarmacêuticos/química , Seringas , Tecnécio/administração & dosagem , Adsorção , Cinética , Compostos Organofosforados/administração & dosagem , Compostos Organofosforados/química , Compostos de Organotecnécio/administração & dosagem , Compostos de Organotecnécio/química , Pertecnetato Tc 99m de Sódio/administração & dosagem , Pertecnetato Tc 99m de Sódio/química , Tecnécio/química , Agregado de Albumina Marcado com Tecnécio Tc 99m/administração & dosagem , Agregado de Albumina Marcado com Tecnécio Tc 99m/química , Medronato de Tecnécio Tc 99m/administração & dosagem , Medronato de Tecnécio Tc 99m/química
12.
Nucl Med Commun ; 20(11): 1047-54, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10572915

RESUMO

Agents used to measure glomerular filtration rate (GFR) give a biexponential plasma disappearance curve on multiple peripheral venous sampling between 20 min and 4 h after intravenous injection. These two exponentials are generally regarded to represent equilibration of agent throughout the extracellular fluid (ECF) space and renal clearance, respectively. In seven subjects undergoing diagnostic arteriography, arterial and antecubital venous plasma samples were obtained up to 60 min in five and up to 120 min in two following simultaneous intravenous injection of 99Tcm-diethylene triamine pentaacetate (99Tcm-DTPA) and inulin. The count rate from 99Tcm was simultaneously recorded over the calf with a collimated scintillation probe in five subjects up to 60 min post-injection. The arterial and venous time-concentration curves were interpolated and subtracted to give a curve of the arterio-venous (A-V) concentration difference, which was then integrated. Arterial time-concentration curves display three exponentials, the first of which has the largest amplitude and disappears by about 20 min. The A-V concentration difference becomes zero at about the same time. The integral of the A-V concentration difference, which represents activity in the interstitial space of the forearm, has a time course consistent with the second compartment of a model of two compartments in series (the first being plasma) and a time course that is reciprocally similar to the first exponential of the triexponential arterial plasma curve. The curve externally recorded by scintillation probe has a shape consistent with a signal that is the composite of interstitial 99Tcm-DTPA and plasma 99Tcm-DTPA activities. The arterial plasma clearance curve of GFR agents is triexponential; the first exponential reflects equilibration of agent between plasma and the interstitial space of carcass tissue (mainly muscle and skin). The second exponential is minor compared with the first; it is not clear what it represents. The third exponential reflects renal clearance.


Assuntos
Taxa de Filtração Glomerular/fisiologia , Compostos Radiofarmacêuticos/farmacocinética , Pentetato de Tecnécio Tc 99m/farmacocinética , Adulto , Algoritmos , Espaço Extracelular/metabolismo , Humanos , Injeções Intravenosas , Inulina/administração & dosagem , Inulina/sangue , Modelos Biológicos , Compostos Radiofarmacêuticos/administração & dosagem , Pentetato de Tecnécio Tc 99m/administração & dosagem
14.
Neurology ; 48(5): 1290-7, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9153460

RESUMO

To determine if there is abnormal phenylalanine and biopterin metabolism in patients with dopa-responsive dystonia (DRD), we measured plasma levels of phenylalanine, tyrosine, biopterin, and neopterin at baseline, and 1, 2, 4, and 6 hours after an oral phenylalanine load (100 mg/kg). Seven adults with DRD, two severely affected children with DRD, and nine adult controls were studied. All patients had phenylalanine and tyrosine concentrations within the normal range at baseline. In the adult patients, phenylalanine levels were higher than in controls at 2, 4, and 6 hours post-load (p < 0.0005); tyrosine concentrations were lower than control levels at 1, 2, and 4 hours post-load (p < 0.05). Phenylalanine to tyrosine ratios were elevated in patients at all times post-load (p < 0.0005). Biopterin levels in the patients were decreased at baseline and 1, 2, and 4 hours post-load (p < 0.005). Pretreatment with tetrahydrobiopterin (7.5 mg/kg) normalized phenylalanine and tyrosine profiles in two adult patients. In the children with DRD, phenylalanine to tyrosine ratios were slightly elevated at baseline. Following phenylalanine loading, the phenylalanine profiles were similar to those seen in the adult patients but there was no elevation in plasma tyrosine. Baseline biopterin levels were lower in the children with DRD than in the adult patients or the controls and there was no increase in biopterin post-load. In both the children and adults with DRD, neopterin concentrations did not differ from control values at baseline or after phenylalanine load. The results are consistent with decreased liver phenylalanine hydroxylase activity due to defective synthesis of tetrahydrobiopterin in patients with DRD. The findings show that a phenylalanine load may be useful in the diagnosis of this disorder.


Assuntos
Di-Hidroxifenilalanina/uso terapêutico , Dopaminérgicos/uso terapêutico , Distonia/sangue , Distonia/tratamento farmacológico , Fenilalanina , Administração Oral , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/sangue , Biopterinas/análogos & derivados , Biopterinas/sangue , Pré-Escolar , Distonia/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neopterina , Concentração Osmolar , Fenilalanina/administração & dosagem , Fenilalanina/sangue , Fatores de Tempo , Tirosina/sangue
15.
Clin Sci (Lond) ; 93(5): 471-7, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9486093

RESUMO

1. After simultaneous intravenous injection as a mixture, 99mTc-labelled diethylenetriaminepentaacetic acid (99mTc-DTPA; molecular mass 492 Da) and inulin (approximately 6000 Da) gave arterial plasma clearance curves consisting of three exponentials, the time courses of which were not significantly different between the two solutes. 2. The ratio of 99mTc-DTPA to inulin concentration in antecubital venous plasma (normalized to the ratio in arterial plasma at 30 s) was 0.6, significantly less than unity, within 2 min after intravenous injection, but increased to reach unity by 60 min. The minimum concentration ratio of 99mTc-DTPA to inulin in arterial plasma was 0.75 at 4 min, also rising to just above unity at 60 min. 3. The extraction fraction from plasma to interstitial space was higher for 99mTc-DTPA (approximately 0.5) than for inulin (approximately 0.2). For both solutes, the net extraction fraction decreased with time, becoming negative at about 25 min after injection. Thereafter, the net extraction fractions remained negative, between -0.05 and -0.1, and not significantly different between the two solutes. 4. 99mTc-DTPA time-activity curves recorded over the limbs with scintillation probes were biphasic, with an initial phase corresponding closely in time with the first exponential of the arterial 99mTc-DTPA plasma clearance curve. The second phase corresponded in time to the intermediate exponential of the arterial 99mTc-DTPA plasma clearance curve. 5. The time course of net 99mTcm-DTPA extraction fraction across the forearm vascular bed was bi-exponential, with phases corresponding in time with the two phases of the limb uptake curves. 6. Deconvolution analysis of the limb time-activity curves, using the arterial time-concentration curve as the input function, gave bi-exponential 99mTc-DTPA impulse response curves in which the time courses of the exponentials corresponded with the first and intermediate exponentials of the arterial 99mTc-DTPA clearance curve. 7. The bi-exponential nature of the equilibrium of 99mTc-DTPA between vascular and interstitial compartments suggests the presence of two separate functional volumes within the interstitial space. Although 99mTc-DTPA and inulin clearly diffuse at different rates across the endothelium, as would be expected from their disparate sizes, the similarity in the time courses of their initial exponentials and simultaneous equalization of transfer rates (i.e. when net extraction fraction was zero) is consistent with the hypothesis that inulin moves initially into a smaller functional interstitial fluid volume than 99mTc-DTPA. The total distribution volumes, however, are not significantly different between the two solutes.


Assuntos
Endotélio Vascular/metabolismo , Inulina/farmacocinética , Pentetato de Tecnécio Tc 99m/farmacocinética , Adulto , Idoso , Espaço Extracelular/metabolismo , Feminino , Antebraço/irrigação sanguínea , Humanos , Masculino , Taxa de Depuração Metabólica , Microcirculação , Pessoa de Meia-Idade
16.
J Neurochem ; 67(2): 752-9, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8764604

RESUMO

hph-1 mice, which have defective tetrahydrobiopterin biosynthesis due to decreased GTP cyclohydrolase I activity, have been used to investigate the effects of tetrahydrobiopterin deficiency on aromatic L-amino acid monooxygenases and brain monoamine metabolism. Liver tetrahydrobiopterin levels were decreased, and tetrahydrobiopterin deficiency and reduced levels of dopamine, norepinephrine, serotonin, and their metabolites in the brain occurred both pre- and postnatally. Chronic subcutaneous tetrahydrobiopterin elevated brain levels to values higher than those seen in controls but had no effect on monoamine metabolism. In vivo activities of tyrosine hydroxylase and tryptophan hydroxylase were significantly decreased. There was a 30% decrease in the in vitro activity of striatal tyrosine hydroxylase and 50% decrease in liver phenylalanine hydroxylase. Western blotting demonstrated that the lower monooxygenase activities resulted from a reduced absolute amount of tyrosine hydroxylase and phenylalanine hydroxylase protein. The findings suggest involvement of tetrahydrobiopterin in the control of the steady-state concentration of the aromatic L-amino acid monooxygenases. In addition, demonstration of central monoamine changes in the hph-1 mouse make it a possible model system for the investigation of the neuropathological mechanisms in Dopa-responsive dystonia, which has recently been linked with mutations in the gene for GTP cyclohydrolase I.


Assuntos
Aminas Biogênicas/metabolismo , Biopterinas/análogos & derivados , GTP Cicloidrolase/deficiência , Animais , Descarboxilases de Aminoácido-L-Aromático/metabolismo , Biopterinas/deficiência , Biopterinas/metabolismo , Corpo Estriado/metabolismo , Feminino , Fígado/enzimologia , Masculino , Camundongos , Camundongos Mutantes , Fenilalanina Hidroxilase/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo
17.
Eur J Nucl Med ; 23(1): 49-54, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8586101

RESUMO

The rate constant (alpha2) of the terminal exponential of the technetium-99m diethylene triamine penta-acetic acid (DTPA) plasma clearance curve is close to the ratio of glomerular filtration rate (GFR) to extracellular fluid volume (ECV) and is therefore a convenient, already normalised, measure of filtration function. Since alpha2 depends on the distribution volume of the tracer, our aim was to compare alpha2 from inulin and 99mTc-DTPA and also to compare the equilibration kinetics of the two filtration markers. Fifty millilitres of 99mTc-DTPA (250MBq) and inulin (10%), mixed in the same syringe, were given by intravenous injection in 15 patients undergoing routine 99mTc-DTPA renography for a variety of clinical indications. Frequent antecubital venous blood samples were taken up to about 4h after injection to construct plasma clearance curves from which GFR, ECV and GFR/ECV (i.e. the reciprocal of mean transit time through the distribution volume) were calculated. 99mTc-DTPA/inulin concentration ratio curves were also constructed after normalisation to the ratio in the syringe. GFR given by the two markers correlated closely (DTPA=0.98.inulin-0.4ml/min; r=0.98). 99mTc-DTPA had the same distribution volume as inulin, had a similar transit time through it and gave the same value of alpha2 (r=0.98). GFR/ECV from 99mTc-DTPA accordingly correlated closely with GFR/ECV from inulin (DTPA=0.75.inulin+0.99 ml/min; r=0.95). Even though the distribution volumes and the times to equilibration (i.e. to reach the terminal exponential) were similar, the distribution volume of 99mTc-DTPA at about 10min after injection was, after subtraction of the plasma volume, about twice that of inulin. We confirm the validity of 99mTc-DTPA for measuring GFR. alpha2 is a convenient measure of GFR, can be based on the terminal exponential of inulin of 99mTc-DTPA curves and can be converted to GFR/ECV with an appropriate scaling factor. The kinetics or the two clearance curves with respect to anatomical correlates of the exponentials and the rates of diffusion throughout the respective distribution volumes requires further study.


Assuntos
Taxa de Filtração Glomerular/fisiologia , Inulina , Renografia por Radioisótopo , Pentetato de Tecnécio Tc 99m , Espaço Extracelular/fisiologia , Humanos , Inulina/sangue , Rim/fisiologia , Reprodutibilidade dos Testes , Fatores de Tempo
18.
Eur J Nucl Med ; 22(4): 330-4, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7607263

RESUMO

A new technique of labelling granulocytes with both technetium-99m hexamethylpropylene amine oxime (HMPAO) and indium-111 in a single protocol was developed in order to exploit the advantages of each radiolabel in clinical and investigative studies. Fourteen patients were included in this prospective study. Granulocytes were labelled with both 111In-tropolonate and 99mTc-HMPAO. In vitro shape change assay and in vivo distribution and recovery studies were performed to assess the activation of and damage to these cells due to the labelling procedure. The comparative kinetics of 111In and 99mTc in the blood, liver, spleen, and bone marrow were studied by blood sampling and dual radionuclide imaging early (1 h) and late (24 h) after injection. The functional integrity of the double-labelled granulocytes and the feasibility of the technique were investigated in 14 patients with a painful prosthetic hip due to causes other than infection. The efficiency of double labelling was 63% (SD 14%) for 111In and 39% (SD 12%) for 99mTc-HMPAO. In vitro granulocyte activation and ex vivo recovery values were comparable to those from single radionuclide labelling. No artefactual granulocyte sequestration was seen in the lungs or liver. The radioactivity was distributed between the liver, spleen and bone marrow and, to a lesser extent, the lung. Early 99mTc counts in the liver, spleen and bone marrow, in relation to background, were significantly higher than 111In counts while the reverse was seen in late images.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Granulócitos , Radioisótopos de Índio , Compostos de Organotecnécio , Oximas , Tropolona , Adulto , Estudos de Viabilidade , Feminino , Quadril/diagnóstico por imagem , Articulação do Quadril/diagnóstico por imagem , Prótese de Quadril , Humanos , Marcação por Isótopo/métodos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Cintilografia , Tecnécio Tc 99m Exametazima
19.
J Appl Physiol (1985) ; 78(4): 1388-95, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7615446

RESUMO

We have developed a technique for measuring the pulmonary granulocyte pool (PGP) as a fraction of the whole body total blood granulocyte pool (TBGP). The technique "captures" a dose of 99mTc-labeled granulocytes in a region of interest (ROI) over the lung during first pass by integrating an input time-activity curve from an ROI over the pulmonary artery, superior vena cava, or right ventricle. The ratio of the estimated first-pass count rate and the count rate in the same lung ROI after equilibration of the cells between the circulating and pulmonary pools (15-30 min) represents the PGP/TBGP. The technique was validated in eight subjects by using 99mTc-labeled macroaggregated human serum albumin. With corrections for background and injected doses, the ratios of first-pass granulocyte-to-macroaggregated human serum albumin count rates given by the three input ROIs were close to unity [superior vena cava 0.98 +/- 0.079 (SD), right ventricle 1.01 +/- 0.070, and pulmonary artery 0.97 +/- 0.073]. Significant increases in PGP/TBGP were demonstrated in systemic inflammation. Thus, in patients with inflammatory bowel disease, it was 0.22 +/- 0.07 (n = 7) compared with 0.08 +/- 0.01 (n = 5) in control subjects. It was also elevated in patients with systemic vasculitis (0.34 +/- 0.07; n = 5), in transplant recipients (0.33 +/- 0.08; n = 5), and in patients with osteomyelitis (0.15 +/- 0.06; n = 4). We conclude that this is a valid technique for quantifying the PGP that is expanded in several conditions associated with systemic inflammation.


Assuntos
Granulócitos/diagnóstico por imagem , Ventrículos do Coração/diagnóstico por imagem , Pulmão/irrigação sanguínea , Artéria Pulmonar/diagnóstico por imagem , Agregado de Albumina Marcado com Tecnécio Tc 99m , Veia Cava Superior/diagnóstico por imagem , Velocidade do Fluxo Sanguíneo , Diagnóstico por Imagem , Doença Enxerto-Hospedeiro/sangue , Doença Enxerto-Hospedeiro/diagnóstico , Granulócitos/patologia , Granulócitos/fisiologia , Ventrículos do Coração/metabolismo , Ventrículos do Coração/patologia , Humanos , Doenças Inflamatórias Intestinais/sangue , Doenças Inflamatórias Intestinais/diagnóstico , Contagem de Leucócitos , Pulmão/diagnóstico por imagem , Pulmão/metabolismo , Osteomielite/sangue , Osteomielite/diagnóstico , Artéria Pulmonar/metabolismo , Cintilografia , Veia Cava Superior/metabolismo , Veia Cava Superior/patologia
20.
Calcif Tissue Int ; 53(4): 237-41, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8275351

RESUMO

Paget's disease of bone is characterized by primary osteoclastic dysfunction and prolonged treatment with conventional medications including calcitonin and etidronate, results in a number of patients becoming refractory to treatment. We have evaluated the effectiveness of three dosage regimes of aminohydroxypropylidene bisphosphonate (pamidronate) in 15 patients with extensive Paget's disease who had become refractory to conventional therapy. Nine patients had pamidronate (intravenous infusion of 30 mg over 4-5 hours at monthly intervals) for 6 months. A further four patients received 30 mg of pamidronate infusion daily for 6 consecutive days and another two patients, 60 mg on 3 consecutive days (total dose of 180 mg/patient). In all three groups the bone-specific alkaline phosphatase and urinary hydroxyproline excretion both fell by 75% (P < 0.001). All but one patient showed a marked improvement in clinical symptomatology (pain and mobility) and biochemical parameters indicating decreased bone turnover. Remissions achieved (> 12 months) with all three regimens were comparable. The pagetic bone pain was reduced and the mobility was significantly improved after 3 months of therapy and was continued for up to 1 year. Currently, it may be difficult to justify the use of intravenous bisphosphonate as the first line of therapy for Paget's disease, but it does seem to have a definite place in patients with severe Paget's disease who do not respond to other therapeutic agents. Here we demonstrate that pamidronate is highly effective in patients with extensive Paget's disease who became refractory to conventional treatment. Further studies are necessary to optimize the dosage and frequency of administration of pamidronate.


Assuntos
Difosfonatos/uso terapêutico , Osteíte Deformante/tratamento farmacológico , Fosfatase Alcalina/metabolismo , Calcitonina/uso terapêutico , Creatinina/urina , Difosfonatos/administração & dosagem , Esquema de Medicação , Resistência a Medicamentos , Ácido Etidrônico/uso terapêutico , Humanos , Hidroxiprolina/urina , Infusões Intravenosas , Osteíte Deformante/metabolismo , Osteíte Deformante/fisiopatologia , Dor/tratamento farmacológico , Pamidronato
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