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Publication
Journal: Annals of Surgery
September/13/1984
Abstract
This study was performed to investigate the mechanism whereby immediate enteral feeding after burn injury reduces postburn hypermetabolism and hypercatabolism. Fifty-seven burned guinea pigs (30% TBSA) were divided into three groups: A (N = 19), given 175 kcal/kg/day beginning 2 hours after burn; B (N = 20), given 175 kcal/kg/day with an initial 72-hour adaptation period; and C (N = 18), given 200 kcal/kg/day with the same adaptation period as B. Resting metabolic expenditure (RME) on PBD 13 was lowest in group A (109% of preburn level), compared with group B (144%, p less than 0.001) and group C (137%, p less than 0.01). On PBD 1, group A had the greatest jejunal mucosal weight and thickness (p less than 0.001), and mucosal weight had negative correlations with plasma cortisol (r = 0.829, p less than 0.001) and glucagon (r = 0.888, p less than 0.001). Two weeks after burn, urinary vanillyl mandelic acid (VMA) excretion, plasma cortisol, and glucagon were lowest in group A (p less than 0.05 to p less than 0.01). These hormones also significantly correlated with RME (p less than 0.01 to p less than 0.001). These findings suggest that immediate postburn enteral feeding can prevent hypermetabolism via preservation of gut mucosal integrity and prevention of excessive secretion of catabolic hormones.
Publication
Journal: Journal of Parenteral and Enteral Nutrition
March/29/1987
Abstract
So that the efficacy of route of nutrient administration in thermal injury could be determined, a comparison was made between immediate enteral vs parenteral feedings in burned guinea pigs. Thirty-five guinea pigs underwent both catheter gastrostomy and jugular vein catheterization. On postoperative day 8, burned animals [30% total body surface area (TBSA)] were divided into an intragastrically (ig) fed group (N = 14) and a parenterally (iv) fed group (N = 14). Animals in each group received 175 kcal/kg/day with a solution of identical nutrient value beginning 2 hr after burn. The body weight change until postburn day (PBD) 8 and the average nitrogen balance were significantly better in the ig group than in the iv group. Values were also higher for the iv group than for the ig group in the early postburn period for urinary vanillyl mandelic acid (VMA) (p less than 0.05), plasma cortisol (p less than 0.05), and plasma glucagon (p less than 0.05). Also, the iv group showed reduced mucosal weight and thickness compared to the ig group on PBD 1 (p less than 0.02). There were significant negative correlations between VMA excretion and body weight change, and between plasma cortisol and jejunal mucosal structure (thickness and weight). These findings suggest that immediate postburn enteral nutrition can provide better nutritional support than parenteral nutrition through the maintenance of gut mucosal integrity and the prevention of increased secretion of catabolic hormones.
Publication
Journal: Journal of neural transmission. Supplementum
November/22/1994
Abstract
The enzyme which has come to be known as monoamine oxidase was discovered in liver over 60 years ago as tyramine oxidase (Hare, 1928). Almost 10 years later, Blaschko et al. (1957a,b) established that epinephrine, norepinephrine and dopamine were also substrates for this enzyme. Zeller (1938) distinguished monoamine oxidase as different from several other amine oxidases, such as diamine oxidase. Although it was generally assumed that catecholamines were metabolized by MAO, this was not established until isotopically labelled epinephrine and an MAO inhibitor became available. Schayer (1951) found that after administration of N-methyl-14C-epinephrine, only about 50% of the radioactivity appeared in the urine, whereas when the 14C label was incorporated into the beta-position on the side chain, almost all of the radioactivity could be recovered. One year later, Zeller et al. (1952) discovered that isonicotinic acid hydrazide (iproniazid) inhibited MAO. When animals pretreated with the MAO inhibitor were administered N-methyl-14C-epinephrine, almost all of the radioactivity was recovered (Schayer et al., 1955), indicating that the enzyme was responsible for the metabolism of about half of the administered catecholamine. Schayer et al. (1952, 1953) had found that five urinary metabolite products of beta-labelled-14C-norepinephrine could be separated by paper chromatography, but the chemical structures of these compounds were not known. Armstrong et al. (1957) showed that 3-methoxy-4-hydroxymandelic acid (vanillyl mandelic acid, VMA) was the major metabolite of norepinephrine and Shaw et al. (1957) demonstrated that large amounts of homovanillic acid (HVA) were excreted in urine after administration of 3,4-dihydroxy-phenylalanine (DOPA). These observations led Axelrod to examine the possibility that O-methylation might precede deamination and to his discovery of catechol-O-methyl transferase (Axelrod, 1957, 1959). At that time it became apparent that there were two possible routes for metabolism of norepinephrine to VMA--either deamination followed by O-methylation or O-methylation and subsequent deamination. The relative roles of these two pathways in terminating the physiological actions of catecholamines then became a focus of attention. Biochemical methods were used to access directly the relative importance of the two metabolic pathways. Physiological methods, based on the effects of drugs which alter metabolism of the catecholamine, were used to examine the role of MAO and COMT in terminating the actions of administered or endogenously released catecholamines.
Authors
Publication
Journal: The Lancet
June/27/1978
Abstract
Four patients with idiopathic orthostatic hypotension (I.O.H.) and one with postural hypotension and diabetes were studied. Plasma-renin activity (P.R.A.) was low and did not rise appropriately with salt restriction and diuretic stimulation. Aldosterone levels were normal and rose with diuretic therapy. Plasma-volume, plasma dopamine beta-hydroxylase, urinary catecholamines, metanephrines, and vanillyl mandelic acid (V.M.A) were normal. Treatment with indomethacin (75-150 mg/day) raised the upright blood-pressure (B.P.) by an average of 20-30 mm Hg diastolic and allowed the four patients with I.O.H. to walk about without orthostatic symptoms but it had no effect in the fifth patient. When indomethacin was discontinued in one patient who had been taking it for 9 months with symptomatic relief, the B.P. fell to pretreatment levels within 48 h. When indomethacin was reinstituted the B.P. rose again. Indomethacin was more effective in these patients than either propranolol or fludrocortisone. There may be an absolute or relative excess of certain vasodepressor prostaglandins in the peripheral vessels which results in pooling of blood and orthostatic hypotension. If this is the case indomethacin might improve the orthostatic symptoms of I.O.H. by its inhibitory effect on prostaglandin synthesis, but its mechanism of action remains to be determined.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
February/6/2008
Abstract
BACKGROUND
Recent evidence suggests that plasma-free metanephrines provide a highly sensitive test in patients requiring exclusion of pheochromocytoma. The diagnostic efficacy of urinary free metanephrines, however, has not been evaluated. OBJECTIVE, DESIGN, SETTING, PATIENTS, AND OUTCOME MEASURES: We compared retrospectively the diagnostic efficacy of 24-h urinary free metanephrines with our currently available measurements of 24-h urinary vanillyl mandelic acid (VMA), urinary catecholamines, and plasma catecholamines in 159 outpatients tested in a tertiary referral center for pheochromocytoma over a 4-yr period.
RESULTS
The sensitivity of urinary free metanephrines was 100% [25 of 25 patients; 95% confidence interval (CI) 86-100%)] compared with the sensitivity of 84% (21 of 25; 95% CI 64-95%) for urinary catecholamines; 72% (18 of 25; 95% CI 51-88%) for urinary VMA; and 76% (16 of 21; 95% CI 53-92%) for plasma catecholamines. The specificity of urinary free metanephrines was 94% (116 of 123; 95% CI 89-98%), compared with the specificity of 99% (127 of 129; 95% CI 96-100%) for urinary catecholamines; 96% (130 of 134; 95% CI 91-98%) for urinary VMA; and 88% (66 of 75; 95% CI 78-94%) for plasma catecholamines. Receiver operating characteristic curves for all test groups were generated. Pairwise comparisons of the area under the receiver operating characteristic curve for urinary free metanephrines with that of each of the other three test groups individually were: 0.993 (95% CI 0.962-0.999) vs. 0.919 (95% CI 0.862-0.957, P = 0.032) for urine catecholamines; 0.993 (95% CI 0.962-0.999) vs. 0.846 (95% CI 0.778-0.900, P = 0.002) for urine VMA; and 0.992 (95% CI 0.945-0.998) vs. 0.852 (95% CI 0.762-0.918, P = 0.009) for plasma catecholamines. Testing with urinary free metanephrines failed to misidentify a single case of pheochromocytoma, compared with four missed cases for urinary catecholamines, seven missed cases for urinary VMA, and five missed cases for plasma catecholamines.
CONCLUSIONS
Urinary free metanephrines were superior to urinary VMA, urinary catecholamines, and plasma catecholamines and can provide a valuable test for diagnosis of pheochromocytoma in adults.
Publication
Journal: Journal of the Chinese Medical Association
October/1/2003
Abstract
Ganglioneuroma is a rare, differentiated, benign and slow-growing tumor that commonly arises from sympathetic ganglion cells. Most of them are asymptomatic and found incidentally. We here report a quite rare case of silent huge ganglioneuroma growing in both posterior mediastinum and retroperitoneum occurring in a 3.5-year-old girl. The patient was relatively well before and incidentally found to have a huge chest mass by chest X-ray film at an episode of respiratory tract infection. Computed tomography showed a huge tumor extending from bilateral posterior mediastinum to the level of the adrenal gland in the retroperitoneum. Initially, neuroblastoma was highly suspected and 24-hour urine vanillyl mandelic acid was slightly elevated. Cytology by bone marrow aspiration revealed no tumor nests or clumps. Biopsy and pathology proved it as ganglioneuroma (GN). Due to too extensive involvement of the tumor and compression of the vital vessels, surgical removal became difficult. The family of the patient refused surgery due to there being no significant symptoms. Because of the potential for growth of unresectable GN and because the component of neuroblasts could not be completely excluded, the patient was still in dangerous status. The only thing we can do is to keep the family alert and continue regular follow-up.
Publication
Journal: European Journal of Clinical Pharmacology
September/16/1982
Abstract
Prazosin is a post synaptic alpha adrenergic blocker effective in hypertension, whose hypotensive effect is unaccompanied by reflex tachycardia or hyperreninemia, nor by other evidence of increased sympathetic activity. We studied the baroreceptor reflex arc as a potential mediator of these effects. Twenty-two essential hypertensive men were treated with prazosin alone versus placebo, and experienced a blood pressure fall (from 114.8 +/- 3.6 down to 101.1 +/- 2.5 mmHg, p less than 0.005) unaccompanied by any change in heart rate, plasma renin activity, or several other indices of sympathetic nervous system activity (plasma dopamine-beta-hydroxylase activity; urinary excretion of free catecholamines and vanillyl mandelic acid; all p less than 0.1). Concomitant with the blood pressure fall, there was a significant depression of baroreflex arc sensitivity, from 11.4 +/- 2.0 ms/mmHg down to 6.6 +/- 1.9 ms/mmHg (p less than 0.05), without an associated change in cardiac vagal inhibition (291.2 +/- 46.2 versus 300.3 +/- 19.2 ms, p greater than 0.1). Baroreflex arc sensitivity depression may in part explain the lack of reflex sympathetic outflow noted during prazosin treatment of hypertension.
Publication
Journal: Journal of Pediatric Hematology/Oncology
July/14/2009
Abstract
OBJECTIVE
The survival of the patients with neuroblastoma has improved in last few decades. But still it depends on various clinical and biological factors. To assess the clinical features and trends in survival, the data for 500 newly diagnosed patients between January 1972 and December 2004 from a single center were retrospectively analyzed.
RESULTS
Histopathologic subtypes were neuroblastoma (NBL) in 462 patients (92.4%) and ganglioneuroblastoma in 38 patients (7.6%). The median age was 2.9 years and Male/Female ratio was 1.3/1. Primary tumor sites were abdomen, thorax, pelvis, neck, and others with the frequency of 72.2%, 14.9%, 3.8%, 3.2%, and 5.9%, respectively. There were 30, 49, 133, 257, 31 patients with stage 1, 2, 3, 4, 4S disease and their 10-year survival rates were 100%, 75.8%, 34.1%, 6.5%, and 59.4%, respectively. The outcome has significantly improved according to 10-year periods. The 5-year overall survival rates were 14%, 26.1%, 39.2%, and 52.4% for the years of 1970s, 1980s, 1990s, and after 2000. Surgical procedure involving total or near total tumor removal improved the survival (P=0.002). Both 5-year overall survival and event free survival rates were higher when partial resection was performed, especially in stage 3 disease (P=0.002 and P=0.02). In multivariate analysis, age above 18 months at diagnosis (P=0.01), stage 4 disease (P<0.001), abdominal primary tumor site (P<0.001), NBL subtype in histopathology (P=0.001), responsiveness to chemotherapy (P<0.001) positive or high Vanillyl mandelic acid levels (P=0.02) and male sex (P=0.008) were the determinants of poor prognosis.
CONCLUSIONS
The survival rates in children with local disease are comparable with the results of developed countries; however, the results in children with advanced disease are still not satisfactory. To improve the outcome, especially in children with advanced disease, more effective chemotherapy regimens and molecular therapies should be investigated. Sharing the knowledge and capacity building to improve the treatment results in NBL are also critical for developing countries.
Publication
Journal: Molecular Genetics and Metabolism
August/13/2008
Abstract
BACKGROUND
Sepiapterin reductase (SR) deficiency is a rare inherited disorder of neurotransmitter metabolism; less than 25 cases have been described in the literature so far.
METHODS
We describe the clinical history and extensive cerebrospinal fluid (CSF) and urine examination of two Greek siblings with the diagnosis of SR deficiency. The diagnosis was confirmed by enzyme activity measurement in cultured fibroblasts and by mutation analysis.
RESULTS
Both patients suffered from a progressive and complex L-dopa responsive movement disorder. Very low concentrations of the neurotransmitter metabolites homovanillic acid (HVA), 5-hydroxyindolacetic acid (5-HIAA) and 3-methoxy-4-hydroxyphenylethyleneglycol (MHPG) were observed in CSF. CSF neopterin and biopterin concentrations were abnormal in one case only, whereas in both cases sepiapterin concentrations were abnormally high and 5-hydroxytryptophan was undetectable. Urine concentrations of HVA, 5-HIAA and vanillyl mandelic acid (VMA) were decreased in both cases. Both patients had no detectable SR enzyme activity in primary dermal fibroblasts, and upon analysis of genomic DNA revealed the same homozygous point mutation introducing a premature stop codon into the reading frame of the SPR gene (mutant allele K251X).
CONCLUSIONS
Our cases illustrate that, apart from HVA and 5-HIAA analysis, the specific quantification of sepiapterin in CSF, rather than neopterin and biopterin alone, is crucial to the final diagnosis of SR deficiency. In addition, urinary concentrations of neurotransmitter metabolites may be abnormal in SR deficiency and may provide an initial indication of SR deficiency before CSF analysis is performed. The known, impressive beneficial response of SR deficient patients to treatment with L-dopa, is illustrated again in our cases.
Publication
Journal: Journal of Oral and Maxillofacial Surgery
January/12/2009
Abstract
OBJECTIVE
The purpose of this article is to report our experience in the management of 18 patients with melanotic neuroectodermal tumor of infancy involving the maxillary alveolus.
METHODS
All patients presented with hard nontender swelling involving the upper alveolus with facial deformity. Analysis included hematocrit, coagulation profile, serum creatinine, and screening for vanillyl mandelic acid and catecholamines. Imaging studies included x-ray of the maxilla and chest, ultrasound of the abdomen, computed tomography scan (1990 to 1999), and magnetic resonance imaging (after 1999). All surgeries were performed using endotracheal anesthesia, and complete gross excision of the tumor was achieved with coverage of the defect with mucoperiosteal flaps. All specimens were subjected to histopathology and immunohistochemistry.
RESULTS
The expansion of the alveolus produced by the tumor improved in 4 to 6 months. Subsequent dentition was affected by the removal of involved tooth buds during the operation. All the patients are in regular follow-up (maximum 206 months) and there has been no local recurrence or distant metastasis. Mean follow-up time was 130.8 months (95% confidence interval, 168.8-210.6). Overall survival at 17 years was 85.6%. Median survival could not be established due to statistically insignificant sample size, while mean survival time was 189.7 months (95% confidence interval, 103.7-157.8).
CONCLUSIONS
In the absence of metastatic disease, melanotic neuroectodermal tumors of infancy can be successfully managed by local excision.
Publication
Journal: Mechanisms of Ageing and Development
March/19/2009
Abstract
Aging results in a general decline in the response to external insults, including acute inflammatory challenges. In young animals, the inflammatory response requires activation of the sympathetic system, including neurotransmitters such as ATP, and catecholamines (epinephrine and norepinephrine). To test whether aging affects activation of this axis, and whether this in turn might affect cytokine release, we administered lipopolysaccharide (LPS) i.p. to adult, middle-aged and aged Fisher 344 rats (6-, 15- and 23-month old, respectively) and evaluated the early (0-12h) serum levels of Neuropeptide-Y (NP-Y), ATP and vanillyl mandelic acid (VMA, as an indirect measurement of catecholamine levels). In addition, we evaluated the association between these factors and serum levels of the cytokines tumor necrosis factor-alpha (TNFalpha) and interleukin-10 (IL-10). Induction of both ATP and NP-Y was markedly reduced in the serum of aged animals, when compared to their younger counterparts, while induction of VMA was not affected by age. In spite of these changes, serum levels of TNFalpha and IL-10 were strongly hyper induced and delayed in aged rats. The results suggest that during aging there is a dysregulation in sympathetic neurotransmitter regulatory mechanisms, and this might play a role in the impairment of the inflammatory response.
Publication
Journal: Biochemical medicine
December/18/1974
Publication
Journal: Nuclear Medicine Communications
January/14/2003
Abstract
Neuroblastomas sometimes recur after the initial disappearance of the tumour. We evaluated the utility of meta-[123I]iodobenzylguanidine (123I-MIBG) scintigraphy for the detection of recurrent neuroblastomas by comparing with the measurement of biochemical markers and clinical findings. Forty patients who had received treatment for neuroblastomas were included in the study. After the disappearance of the initial tumours, periodic measurements of urinary vanillyl mandelic acid, homovanillic acid and serum neuron specific enolase values, and an 123I-MIBG scintigraphy were performed. Whenever an abnormal finding was observed, other appropriate examinations and/or follow-up examinations were performed to elucidate the true state of the patient. Eleven recurrent episodes in eight patients were observed. Most of them occurred in the bone marrow or bone. Corresponding symptoms were observed in only two episodes; the other episodes were asymptomatic, and discovered by the periodic examinations. 123I-MIBG scintigrams visualized the recurrent tumours in 10 (91%) episodes. Elevated tumour markers were observed in only three episodes. 123I-MIBG scintigrams visualized most of the recurrent tumours, unless they were accompanied by any symptoms or elevations in biochemical tumour markers. Periodic examinations with 123I-MIBG scintigraphy appears to be a useful technique for the detection of the recurrences.
Publication
Journal: International Journal of Neuropsychopharmacology
April/13/2015
Abstract
Patients with 22q11 deletion syndrome (22q11DS) have a high prevalence of psychiatric disorders and intellectual disability. At present the neurobiology underlying psychopathology in 22q11DS is still not understood. In the present study, we analyzed urinary serotonergic, dopaminergic and noradrenergic markers in 67 adults with 22q11DS. Levels of serotonin and the catecholamine metabolite homovanillic acid were significantly lower in the 22q11DS subjects compared to healthy controls. Within the 22q11DS group, levels of dopamine, homovanillic acid, norepinephrine, vanillyl mandelic acid and serotonin positively correlated with Full Scale Intelligence Quotient scores. Our results suggest that cognitive deficits in 22q11DS are associated with abnormal function of several neurotransmitters.
Publication
Journal: Acta Neurologica Scandinavica
July/24/2007
Abstract
OBJECTIVE
We aimed to evaluate the interictal cardiovascular autonomic functions in pediatric patients with idiopathic epilepsy, both partial and generalized.
METHODS
The study included 25 patients with idiopathic epilepsy and 50 control subjects. Patients underwent five standardized clinical cardiovascular reflex autonomic tests [resting heart rate (HR), HR response to deep breathing and to Valsalva maneuver, the 30:15 ratio of HR response to standing, and blood pressure response to standing], as well as a 12 lead surface electrocardiogram. Heart rate variability (HRV) was tested via 24-h Holter monitoring and the time domain parameters (SDNN, PNN50, rMSDD) were assessed. Excretion of vanillyl mandelic acid and metanephrine was measured in 24-h urine collection.
RESULTS
Clinical reflex autonomic tests showed mild dysfunction in 8%, moderate dysfunction in 44% and severe dysfunction in 4% of patients. The HRV parameter, SDNN, was reduced in all age groups, while rMSDD and PNN50 were reduced only in the older age group. Metanephrine levels were significantly reduced in the patients group. Patients with uncontrolled epilepsy had a significantly higher frequency of autonomic dysfunction as assessed by clinical scoring.
CONCLUSIONS
Cardiac autonomic dysfunction is not uncommon in pediatric patients with epilepsy. Altered cardiovascular regulation seems to be related to the epilepsy itself rather than to the characteristics of the disorder.
Publication
Journal: Annals of tropical paediatrics
April/6/2000
Abstract
We retrospectively analysed the epidemiological features and the importance of biochemical, histological and genetic parameters in predicting survival in 14 Namibian and 34 South African children treated for neuroblastoma (NB) from 1983 to 1997. Curative treatment consisted mainly of total (13%) or partial (44%) resection after chemotherapy (cyclophosphamide and doxorubicin x6 courses or carboplatin, etoposide, epirubicin and cyclophosphamide x6 courses). Localized radiotherapy with curative intent was given to 33% of patients. The male:female ratio was 0.9. The median age was 18 months (range 1-116) and was comparable in white, black and mixed ethnic patients. Primary disease was located in the abdomen (75%), thorax (15%), pelvis (5%) or elsewhere (5%). Evans stage distribution was: stage I, 2%; stage II, 19%; stage III, 21%; stage IV, 50%; and stage IVS, 8%. Stage III/IV disease was more common in black than in white children (p = 0.0001). Urinary vanillyl mandelic acid was elevated in 63% of those tested. Survival after 5-163 months' follow-up was 90% for stages I and II combined (median 2983, range 798-4661 days), 51% for stage III (median 367, range 61-5001 days), 6% for stage IV (median 227, range 20-4379 days) and 50% for stage IVS (median 532, range 54-1543 days). All seven children with para-spinal tumours survived. Individual factors associated with significantly poorer survival were elevated serum lactate dehydrogenase (p < 0.001), Joshi histological risk categorization adapted for age (p = 0.039), n-myc amplification (p = 0.006) and diploidy or tetraploidy (p = 0.006). All seven children with serum ferritin exceeding 149 ng/ml at the time of diagnosis died and survival was 33% in children with 1p deletion and 67% in those without, but the numbers were too small to achieve significance. These findings confirm the benefit of simple biochemical tests and histology in identifying those who are likely to respond favourably to conventional chemotherapy and surgery. Supportive genetic tests on formalin-fixed paraffin-embedded tumour tissue contributed to predicting outcome in 21 patients.
Publication
Journal: Journal of the Royal College of Physicians of London
December/14/1995
Abstract
Despite advances in biochemical assessment and imaging, phaeochromocytoma remains a difficult diagnosis. Using the names of patients whose death certificate listed phaeochromocytoma as a cause of death, a retrospective survey of 62 deaths from phaeochromocytoma (48 benign, 14 malignant) was carried out. All deaths occurred between 1981 and 1989, so the pitfalls uncovered reflect recent practice. A substantial proportion presented with abdominal pain and vomiting, dyspnoea, left ventricular failure or hypotension rather than the classical symptoms. These presentations were more common in this autopsy series than in prospective series of consecutive patients. Diagnosis in the presence of classical symptoms was often delayed but, once it was made, elective excision was relatively safe. A personal or family history of symptoms suggesting inherited diseases associated with phaeochromocytoma was not always given due weight. Biochemical tests, particularly 24 hour urinary vanillyl mandelic acid, often gave contradictory results; the limits of their predictive power should be better appreciated. Anaesthesia and surgery in the presence of undiagnosed phaeochromocytoma was the cause of death in 16 of 62 cases. Recommendations to improve the accuracy of diagnosis are made.
Publication
Journal: Cellular and Molecular Neurobiology
October/5/1988
Abstract
1. Dopaminergic neurotransmission in brain is receiving increased attention because of its known involvement in Parkinson's disease and new methods for the treatment of this disorder and because of hypotheses relating several psychiatric disorders to abnormalities in brain dopaminergic systems. 2. Chemical assessment of brain dopamine metabolism has been attempted by measuring levels of its major metabolite, homovanillic acid (HVA), in cerebrospinal fluid, plasma, or urine. Because HVA is derived in part from dopamine formed in noradrenergic neurons, plasma levels and urinary excretion rates of HVA do not adequately reflect solely metabolism of brain dopamine. 3. Using debrisoquin, the peripheral contributions of HVA to plasma or urinary HVA can be diminished, but the extent of residual HVA formation in noradrenergic neurons is unknown. By measuring the levels of methoxy-hydroxyphenylglycol (MHPG) in plasma or of urinary norepinephrine metabolites (total MHPG in monkeys; the sum of total MHPG and vanillyl mandelic acid (VMA) in humans) along with HVA, it is possible to estimate the degree of impairment by debrisoquin of HVA formation from noradrenergic neuronal dopamine and thereby better assess brain dopamine metabolism. 4. This method was applied to a monkey before and after destruction of the nigrostriatal pathway by the administration of MPTP.
Publication
Journal: British heart journal
November/30/1970
Abstract
The following endocrine function parameters were studied serially in a group of 10 patients with recent myocardial infarction: blood and urinary levels of epinephrine and norepinephrine, urinary excretion of vanillyl-mandelic acid; protein-bound iodine, Hamolsky test (Hamolsky, Stein, and Freedberg, 1957); blood insulin; 24-hour urinary excretion of 17-hydroxycorticoids, sodium, and potassium. The acute phase of myocardial infarction, especially in those patients with a severe clinical course (rhythm disturbances, coronary insufficiency, circulatory failure), was associated with disturbed endocrine reactivity. The most frequent and the earliest feature was the increased level of the 24-hour urinary excretion of epinephrine, combined with a pronounced decrease in blood insulin level. Later in the course of the disease, as the adrenergic reactivity returned to normal, there was an increase in blood insulin to normal levels. In 3 patients with severe clinical symptoms of acute myocardial infarction, there were, in addition to the increased 24-hour urinary excretion of catecholamines, a decreased blood insulin, higher than normal levels of protein-bound iodine, and of the Hamolsky test. One of these patients developed hypoadrenia. It is possible that the abnormal endocrine reactions accelerate the catabolic processes within cardiac tissue (catecholamines, thyroid hormones), especially when there is a possible functional deficiency of hormones, occurring as a general adaptation reaction to stress (cortisol, insulin). The disturbances that follow may be dangerous for the patient.
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Publication
Journal: Journal of Endocrinology
January/1/1997
Abstract
A novel animal experimental model involving the human, poorly differentiated, and adrenergic neuroblastoma cell line SH-SY5Y xenotransplanted to subcutaneous tissue of 13 nude rats (WAG rnu/rnu) was used to investigate the usefulness of six proposed neuroblastoma markers. It was shown that the plasma concentrations of human chromogranin A (CgA) as measured by RIA were directly proportional to tumour volume (r = 0.83, P < 0.001). To rule out possible liberation of CgA by tumour cell lysis, the CgA degradation product pancreastatin was also measured in plasma by a specific RIA, but was not detectable. Plasma neurone-specific enolase (NSE) was elevated in tumour-bearing animals (P < 0.01), but did not correlate with tumour volume (r = 0.49, P>> 0.05). Urine homovanillic acid (HVA), detected by HPLC, was elevated in tumour-bearing animals (P < 0.01), but did not correlate with tumour volume (r = -0.32, P>> 0.05). Urine vanillyl mandelic acid was not detectable. Urine dopamine was found in low concentrations that did not correlate with tumour volume. In summary, although plasma NSE and urinary HVA were elevated in tumour-bearing animals only plasma CgA correlated with tumour burden. This makes CgA a promising biochemical marker for neuroblastomas.
Publication
Journal: Japanese Journal of Clinical Oncology
November/29/1994
Abstract
We tried to discriminate between cases of spontaneous regression and non-regression during mass screening for neuroblastoma, taking advantage of differences in respect to the urinary homoranillic acid/vanillyl mandelic acid (HVA/VMA) ratio and the original tumor site among true positive, false negative and natural occurrence cases. After classifying them into a total of six groups depending on the two factors, ratio: < 1, 1-2 or>> or = 2 and tumor site: adrenal or extra-adrenal in origin, we calculated the mathematical probability of a given true positive case being one of spontaneous regression. A tumor of extra-adrenal origin was likely to regress spontaneously, especially one with an HVA/VMA ratio < 1 or>> or = 2 (82.2-100%). A tumor of adrenal origin with an HVA/VMA ratio < 1 seemed unlikely to regress spontaneously (0-4%). The present method, employing simple preoperative information, would be useful in future for the selection of true positive cases which should be observed without treatment.
Publication
Journal: North American Journal of Medical Sciences
October/1/2012
Abstract
BACKGROUND
Ganglioneuromas are benign tumors of the sympathetic nervous system that rarely arise in the adrenal gland. Majority of cases are detected incidentally since they are usually asymptomatic. Up to the current era of laparoscopic adrenal mass excision, this unusual entity has not been adequately reported in the surgical literature.
METHODS
A 51 year old male with history of hypertension was found to have abdominal bruit during a regular physical examination. A 4 cm right adrenal mass with upper pole calcification and a 6 cm retro-pancreatic mass were subsequently found on a computed tomography scan. Endoscopic ultrasound-guided needle biopsy was indeterminate. Preoperative endocrine evaluation showed mildly elevated vanillyl mandelic acid with normal 24-hour cathecolamine, metanephrine and cortisol levels. Histopathologic examination after an uneventful laparoscopic excision was consistent with ganglioneuroma.
CONCLUSIONS
Ganglioneuroma occurs rarely in adrenal gland and preoperative diagnosis is difficult since symptoms are usually nonspecific. Due to widespread utilization of abdominal imaging, however, it should be included in differential diagnosis of adrenal or retroperitoneal mass. Histopathologic examination is currently the mainstay of diagnosis.
Publication
Journal: Journal of Pediatric Surgery
November/17/2003
Abstract
OBJECTIVE
Neuroblastoma is a common pediatric tumor of the sympathetic nervous system. Unlike the ones found in older children, the tumors found in patients younger than one year of age often show spontaneous differentiation and regression. Peroxisome proliferator-activated receptor gamma (PPAR-gamma), a member of the nuclear hormone receptor superfamily is expressed in several human cancers. Recently, PPAR-gamma has been reported to be expressed in neuroblastoma, and the agonist of this receptor caused differentiation of neuroblastoma cells.
METHODS
In this report we studied the expression of PPAR-gamma mRNA, using LightCycler in neuroblastoma samples diagnosed in 17 patients under the age of one year.
RESULTS
Twelve samples showed PPAR-gamma mRNA expression. There was no significant difference in the PPAR-gamma mRNA expression based on age, histology, staging, and DNA ploidy. The PPAR-gamma mRNA expression level was significantly correlated with the change in urinary vanillyl mandelic acid (VMA). The neuroblastoma samples resected from patients who showed a decrease in their urinary VMA before the operation showed significantly higher PPAR-gamma expression than those from patients who showed an increase in their urinary VMA before the operation.
CONCLUSIONS
PPAR-gamma may have played a role in the reduction of VMA and possibly in the regression of early-onset neuroblastoma.
Publication
Journal: In Vivo
April/16/2003
Abstract
BACKGROUND
Extra-adrenal paraganglioma (pheochromocytoma) is a rare tumor. Herein we describe the clinical and pathological findings in patients with paragangliomas of the urinary bladder, seminal vesicle and retroperitoneum.
METHODS
Between January 1994 and January 2001, extra-adrenal paragangliomas were diagnosed in 7 patients: 3 males and 4 females. The mean age of our patients was 32 +/- 15.9 years. We reviewed the clinical data. Urinary metanephrines and vanillyl mandelic acid and blood catecholamine levels were estimated in 4 cases. CT scan and/or MRI were used in the imaging of all cases. 123I-MIBG was used in only 1 patient, who harbored multiple tumors. All the patients but one underwent surgical treatment.
RESULTS
The definitive diagnosis was made by histopathological examination of the removed tumors and was confirmed in all cases by the immunohistochemical stains of chromogranin A and S100 protein. There was metastasis in the pelvic lymph nodes in 1 patient. Follow-up ranged from 3 to 82 months (mean = 37.9 +/- 25.8). The catecholamine level was elevated in 3 patients under basal conditions and during endoscopic resection of the tumor in a fourth patient. In all cases, the catecholamine level was normalized after surgery. There was no recurrence or metastasis in any case following surgery.
CONCLUSIONS
Pre-operative diagnosis of nonfunctioning bladder paraganglioma is difficult, but the tumors should be suspected in patients who have hypertension, hematuria or mass effects due to the tumor growth in the pelvis and/or retroperitoneum. Six of the seven cases reported here were found in the usual locations: 3 in the urinary bladder, 2 in the renal hilum and 1 in the organ of Zuckerkandl. One patient had multiple tumors, including a paraganglioma of the seminal vesicles. Resection is the treatment of choice, and in the case of urinary bladder paraganglioma should include total cystectomy. In patients with unresectable multiple tumors, medical therapy may be used to control hypertension.
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