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H R Ham

Publications and source records attributed to H R Ham.

At least 55 records · Page 3Linked to original sources
PubMed1995

Aminopyrine breath test improves long-term prognostic evaluation in patients with alcoholic cirrhosis in Child classes A and B.

In a 4-year survival study, we evaluated the prognostic value of the aminopyrine breath test and the Child-Turcotte-Pugh score in 190 alcoholic patients. Using aminopyrine breath test results, the patients were stratified into group 1 (aminopyrine breath test > 2%), group 2 (1% < or = aminopyrine breath test < 2%) and group 3 (aminopyrine breath test < 1%). Survival rates at 4 years were 68% in group 1, 35% in group 2 and 17% in group 3. Using the Child-Turcotte-Pugh score, survival rates at 4 years were 67% in Child-Turcotte-Pugh class A, 40% in class B and 7% in class C. To assess the value of aminopyrine breath test as an adjunct to Child-Turcotte-Pugh score in prognostic evaluation of patients with cirrhosis, two approaches have been used: a regression analysis using Cox's proportional hazard model by including the Child-Turcotte-Pugh score and aminopyrine breath test value, and the log-rank test to assess the prognostic value of aminopyrine breath test in each Child-Turcotte-Pugh class separately. The regression analysis showed that both parameters, the Child-Turcotte-Pugh score and the aminopyrine breath test results, were accepted in the model, suggesting that the aminopyrine breath test was still significantly related to survival once the Child-Turcotte-Pugh score had been entered into the model. Analysis of the prognostic value of the aminopyrine breath test in each Child-Turcotte-Pugh class separately indicated, however, that the contribution was negligible in the Child-Turcotte-Pugh class C.(ABSTRACT TRUNCATED AT 250 WORDS)

Aminopyrine↗
PubMed1995

A radionuclide study of regional gastric motility.

The aims of this research were to study some methodological aspects of radionuclide methods for assessing regional gastric motility and to determine the parameters that can be extracted along with their normal values or patterns. During the lag phase, the antral contraction curve showed three different patterns. At the beginning, the antral activity was too low to be analysed. Irregular variation of the count rate was then observed, followed by a more regular contraction. The application of Fourier transformation to the well-defined cyclical count rate variations revealed two areas with high amplitude values but with phase opposition. No peristaltic wave could be identified. After the lag phase, the antral curve showed cyclical variations of count rates with a frequency of about three cycles per minute. Slightly displaced curves but with a much lower amplitude were observed at different parts of the stomach. Several factors were found to influence the antral contraction curve, including the choice of region of interest and time since the last meal. Irregularities in the antral curve, both in terms of frequency and of amplitude, were not unusual in healthy subjects. These should be taken into account when interpreting antral contraction curves. The phase image showed a well-defined peristaltic contraction pattern. Three 360 degrees cycles were usually observed throughout the stomach, suggesting that the time necessary for a peristaltic wave to sweep through from the upper part of the stomach to the antrum is about 1 min. Similar phase images were obtained in all subjects regardless of the amount of time since the meal containing the radioactive tracer, suggesting that gastric peristalsis can easily be assessed and interpreted. The amplitude image showed high amplitude in the antral area and in the greater curvature of the stomach. In the lesser curvature, the amplitude was much lower. Unlike the phase image, however, there was marked variability in the regional amplitude distribution. The value of the regional amplitude distribution for evaluating regional gastric motility is therefore limited.

Adult↗
PubMed1995

Thallium-201 per rectal scintigraphy improves prognostic evaluation in alcoholic liver cirrhosis of low and mid severity.

OBJECTIVES: The aim of this work was to assess the contribution of thallium-201 chloride (Tl-201) per rectal scintigraphy in long term prognostic evaluation of alcoholic, cirrhotic patients. METHODS: The data obtained from 170 biopsy-proven cirrhotic patients have been used in this 4-yr survival study. The severity of the liver disease was assessed by using the classic Child-Turcotte score as modified by Pugh (CTP score). RESULTS: In patients belonging to CTP class A and CTP class B, the Tl-201 test allowed the identification of subgroups with different survival rates. In these two classes of patients, the Tl-201 per rectal scintigraphy could be used for improving prognostic evaluation. In patients of class C on the other hand, 4-yr survival rates were very low, and the Tl-201 test did not bring significant additional prognostic information. CONCLUSIONS: Therefore, we suggest performing the Tl-201 test in cirrhotic patients of classes A and B as defined by the CTP score.

Case-Control Studies↗
PubMed1994

Estimation of normal chromium-51 ethylene diamine tetra-acetic acid clearance in children.

In order to estimate the normal range of chromium-51 ethylene diamine tetra-acetic acid (EDTA) clearance in children, we selected a series of 256 patients with past or present urinary tract infection who showed, at the time of the clearance determination, normal technetium-99m dimercaptosuccinic acid (DMSA) scintigraphy and normal left to right DMSA relative uptake. The clearance was calculated by means of either the simplified second exponential method or the 120-min single blood sample; Chantler's correction was used in order to correct for having neglected the first exponential. There was a progressive increase in clearance from the first weeks of life (mean value around 1 month: 55 ml/min/1.73 m2), with a plateau at around 18 months. Between 2 and 17 years of age, the clearance values remained constant, with a mean value of 114 ml/min/1.73 m2 (SD: 24 ml/min); this is similar to the level described for inulin clearance. No significant differences were observed between boys and girls, or between clearance values calculated with one or with two blood samples. Taking into account the hour of intravenous injection of the tracer, we did not observe any influence of the lunchtime meal on the distribution of the 51Cr-EDTA clearance values.

Adolescent↗
PubMed1994

Effect of hyperfiltration on long-term follow-up of glomerular filtration rate in male Wistar rats.

It has been suggested that a prolonged course of hyperfiltration could lead to progressive deterioration of renal function. In order to test this hypothesis, the following protocol was applied to 60 male Wistar rats. At 12 weeks of life, the rats were submitted to a surgical procedure: sham operation (25 rats), unilateral nephrectomy (25 rats) or 3/4 nephrectomy (10 rats). The three groups were again divided into two subgroups: one with high-protein intake (36%) and one with a low-protein intake (12%). In order to avoid any additional traumatic procedure which could shorten the animal's life, the glomerular filtration rate (GFR) was measured without blood sampling, using a previously validated technique based on an image recorded by a gamma camera between the 9th and the 10th min after intravenous injection of 99m technetium diethylenetriaminepentaacetate (DPTA). The sum of both kidneys and bladder activity was expressed as a percentage of the injected dose. The test was performed before surgery and every month thereafter. Six weeks after surgery, the highest filtration rate was found in the rats with "two kidneys/high-protein diet", followed by the "two kidneys/low-protein diet", the "one kidney/high-protein diet", the "one kidney/low-protein diet" and the "1/2 kidney". The overall GFR in the one kidney/high-protein diet rat and in the 1/2 kidney rat was respectively 80% and 55% of the pre-operative values. Until 109 weeks of age, the survival rate was comparable in the five groups of rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

Electroencephalographic mapping and 99mTc HMPAO single-photon emission computed tomography in carbon monoxide poisoning.

STUDY OBJECTIVE: To investigate whether topographic analysis of EEG mapping and technetium-99m (99mTc) hexamethylpropylenamine oxide (HMPAO) brain single-photon emission computed tomography (SPECT) can detect cerebral anomalies in the acute phase of carbon monoxide poisoning. DESIGN: Twelve patients aged 18 to 55 years with severe carbon monoxide poisoning and no history of neurologic disorder were evaluated. Either nasal (5 patients) or hyperbaric (7 patients) oxygen therapy was administered. Criteria for hyperbaric oxygen therapy were blood CO of more than 20%, loss of consciousness, pregnancy, or signs of cardiac injury. After oxygen treatment, all patients had a blood CO value of 0% and no patient had persistent acute signs of toxicity. Patients then were investigated by confentional EEG, EEG mapping, and 99mTc HMPAO brain SPECT. These procedures were performed on the day of admission. PARTICIPANTS: After nasal (5 patients) or hyperbaric (7 patients) oxygen therapy was administered, 12 adults with severe carbon monoxide poisoning were evaluated. All studies were performed on the day of admission. MEASUREMENTS: Conventional EEG, EEG mapping, and 99mTc HMPAO brain SPECT. RESULTS: While classic EEG was normal in 9 of 12 patients and showed diffuse anomalies in 3, EEG mapping and 99mTc HMPAO brain SPECT demonstrated unilateral or bilateral regional anomalies in 8 of 12 patients. Anomalies were localized in temporo-parieto-occipital areas, the watershed areas of the major cerebral arteries, or in temporal cortex. CONCLUSION: These preliminary results suggest that EEG mapping and 99mTc HMPAO brain SPECT can be complementary tools to diagnose early regional cerebral anomalies in carbon monoxide-poisoned patients.

Acute Disease↗
PubMed1994

Esophageal transit of liquid in chronic alcoholism in patients with cirrhosis. Influence of esophageal varices.

Disturbances of esophageal motility are often encountered in chronic alcoholism, and numerous physiopathologic mechanisms responsible for this alteration have been documented. The exact role of esophageal varices, however, in inducing esophageal transit abnormalities remains unclear. In this study using scintigraphy, the authors studied esophageal transit in a large number of patients with cirrhosis to assess the direct effect of esophageal varices. Esophageal transit was found altered in 58 out of 141 patients with cirrhosis (41.1%). It was prolonged in 47.3% of patients with esophageal varices and in 29.2% of patients without varices (P < 0.05). The frequency of esophageal transit alteration was also related to the Child-Turcotte-Pugh (CTP) score, an index of the severity of liver disease (P < 0.01). The relationship between CTP class and transit alteration remained statistically significant in the group of patients with esophageal varices (P < 0.05). Conversely, when patients in each CTP class were analyzed separately, the frequency of esophageal transit abnormalities was not different in patients with and without esophageal varices. These results suggest that the severity of cirrhosis, rather than the presence of esophageal varices, constitutes the major factor in inducing esophageal transit alteration in patients with cirrhosis.

Adult↗
PubMed1994

Bilateral cerebral mediofrontal hypoactivity in Tc-99m HMPAO SPECT imaging.

Fifteen patients who had bilateral mediofrontal hypoactivity and 30 control subjects without this SPECT anomaly underwent Tc-99m HMPAO brain SPECT imaging. Bilateral mediofrontal hypoactivity was found in various neurologic disorders, including subcortical arteriosclerotic encephalopathy, lacunar state, chronic alcoholism, progressive nonvascular dementia, carbon monoxide poisoning, and diabetes mellitus. This SPECT abnormality was, however, specifically associated with three clinical signs: motor disabilities predominating in the lower limbs, urinary incontinence, and akinetic mutism.

Akinetic Mutism↗
PubMed1994

Improving the accuracy of 99Tcm-mercaptoacetyltriglycine clearance by using two blood samples instead of one? Paediatric Task Group of the EANM.

From a database of 133 patients (98 children and 35 adults) who underwent multiple blood sampling for 99Tcm-mercaptoacetyltriglycine (MAG3) clearance, we determined simplified algorithms allowing the estimation of clearance. A one-compartment model with two blood samples was applied. The best choices for the adult population were the 12 and 90 min blood samples, giving a standard error of the estimate (S.E.E.) of less than 10 ml min-1 1.73 m-2; for the children, the 10 and 80 min blood samples gave a S.E.E. of 20 ml min-1 1.73 m-2; for both the adults and the children, the 10 and 70 min blood samples gave the best results with, however, a S.E.E. of 19 ml min-1 1.73 m-2. The use of such a combined algorithm will therefore result in a degradation of the results in adults, suggesting that a separate algorithm for each group is preferable. We compared the accuracy of the two blood sample method to the one blood sample method based on previously published algorithms for children and adults, respectively. The S.E.E. was significantly lower, in adults as well as in children, using the empirical two blood sample method. This two blood sample method seems potentially useful for routine practice in adult patients. The advantages of using such a method in children is balanced by the practical problems inherent in the need to take a second blood sample during the first 10 min, at a time when the plasma activity is rapidly decreasing.

Adult↗
PubMed1994

Prognostic value of thallium-201 per rectum scintigraphy in alcoholic cirrhosis.

METHODS: In a 4-yr survival study, the prognostic value of the inferior mesenteric shunt, as evaluated by 201Tl per rectum scintigraphy, was assessed in 170 alcoholic cirrhotic patients. The global severity of the hepatic disease was assessed by the Child score, and specific hepatocellular function was evaluated by the aminopyrine breath test. Using 201Tl scintigraphy, three groups were considered: group I, heart-liver activities ratio (H/L ratio) < or = 0.5, n = 55; group II, H/L between 0.5 and 0.85, n = 50; and group III, H/L > 0.85, n = 65. RESULTS: The 4-yr survival rates in the three groups were 76%, 36% and 18%, respectively. The log-rank test showed that the differences between the groups were statistically significant. Regression analysis using Cox's proportional-hazards model showed that the three parameters, Child score, aminopyrine breath test results and H/L ratio were significantly related to survival. CONCLUSION: The inferior mesenteric shunt per se has a prognostic value in alcoholic cirrhosis. Moreover, the H/L ratio provides additional information on survival after the Child score and the aminopyrine breath test results have been taken into account.

Administration, Rectal↗
PubMed1993

Metabolic changes in the rat brain after acute and chronic ethanol intoxication: a 31P NMR spectroscopy study.

In this work, 31P phosphorus NMR (31P NMR) studies of the brain have been conducted in rats acutely and chronically intoxicated with ethanol. In both groups, changes in levels of high-energy phosphates were observed: increase of phosphocreatinine (PCr)/beta AaTP and PCr/inorganic phosphate (Pi) in acute and long-term ethanol exposure, and decrease of Pi/beta ATP after acute ethanol administration. These changes in high-energy phosphates, indicative of a reduction of adenosine triphosphate (ATP) and PCr consumption (PCr+ ADP+ H+ ATP+ Cr; ATP ADP+ Pi), suggest a reduction of cerebral metabolism both in acute and chronic ethanol exposure. In addition, in the group of rats chronically intoxicated with ethanol, there were variations in phosphodiester peak intensities (decrease of phosphomonoester (PME)/phosphodiester (PDE), increase of PDE/beta ATP), suggesting increased breakdown of membrane phospholipids. These changes could provide a metabolic explanation for the development of cerebral atrophy in chronic alcoholism.

Adenosine Triphosphate↗
PubMed1993

Acute effects of nifedipine on systolic and diastolic ventricular function in patients with chronic obstructive pulmonary disease.

To evaluate how nifedipine influences systolic and diastolic ventricular function, the effects of 20 mg sublingual nifedipine were studied in 13 stable COPD patients. Nifedipine induced no change in mean pulmonary arterial pressure, decreased mean arterial pressure, pulmonary and systemic vascular resistance index, and increased heart rate and cardiac index. It also caused an increase in right and left ventricular ejection fractions. The end-diastolic volume index of both ventricles remained unchanged, whereas the end-systolic volume index tended to decrease without reaching a significant level, and the right ventricular contractility increased. After nifedipine administration, right and left ventricular compliance increased. This study suggests that short-term administration of nifedipine improves the systolic function by a decrease in ventricular afterload and an increase in ventricular contractility and increases the ventricular compliance by a reflex sympathetic stimulation and an afterload reduction.

Administration, Sublingual↗
PubMed1993

Dose dependency of aminophylline effects on hemodynamic and ventricular function in patients with chronic obstructive pulmonary disease.

The effects of aminophylline on pulmonary vascular tone, systemic hemodynamics, and ventricular ejection fractions reported in the literature show some discrepancies. We therefore studied in COPD patients the effects of aminophylline on hemodynamics, on ventricular ejection fractions, and on systolic and diastolic functions of each ventricle, and we measured simultaneously the blood level of the drug. The analysis of the data revealed a relationship between the blood level of aminophylline and the variations of right ventricular ejection fraction (RVEF) (r = 0.83, p = 0.005), left ventricular ejection fraction (LVEF) (r = 0.76, p = 0.017), pulmonary vascular resistance index (PVRI) (r = -0.58, p = 0.096), systemic vascular resistance index (SVRI) (r = -0.60, p = 0.08), and right ventricular peak systolic pressure/end-systolic volume index (RVPSP/ESVI) (r = -0.75, p = 0.02). Modifications of ejection fractions and vascular resistance indices were correlated for both ventricles (RVEF vs PVRI, r = -0.77, p = 0.01; LVEF vs SVRI, r = -0.76, p = 0.02). Finally, RVEF modifications was also correlated to RVPSP/ESVI variation (r = 0.78, p = 0.01). These results suggest that even within the therapeutic range (10 to 20 mg/L), the effects of aminophylline seemed to depend on its blood level. This dose dependency could explain the contradictory data reported in the literature concerning the effects of aminophylline on pulmonary and systemic hemodynamics and on ventricular function.

Aged↗
PubMed1993

Prediction of cerebral palsy in high-risk neonates: a technetium-99m-HMPAO SPECT study.

In infants who have experienced prenatal or perinatal injury, it is often difficult, on the basis of clinical examination and conventional investigations (electroencephalogram, cranial ultrasound scan), to diagnose those with brain damage and to predict the type and the severity of subsequent neurological handicaps. We investigated the predictive value of 99mTc-HMPAO brain SPECT performed in the first weeks of life in high-risk neonates. Right-left asymmetries in tracer uptake had no predictive value, regardless of their localization or severity. On the other hand, a change in antero-posterior rCBF distribution was found in 7/10 of neonates with adverse outcome (death, major neurological sequelae) and in none of the 78 neonates with no major motor neurological sequelae. Compared to conventional investigations, 99mTc-HMPAO brain SPECT did not provide additional predictive information when neurological examination, electroencephalogram and cranial ultrasonography were all normal or all abnormal. Conversely, in the 30 patients with anomalies on one or two of the above investigations, SPECT showed an abnormal antero-posterior pattern in 4/6 neonates with major neurological sequelae and no change in the antero-posterior rCBF distribution in the 24 infants who developed normally. In conclusion, our results suggest that 99mTc-HMPAO brain SPECT, when performed in the first weeks of life, can be useful in high-risk neonates to predict occurrence of major neurological handicaps. Because of the relative invasive character of HMPAO scan in neonates and the overall accuracy of the noninvasive tests, radionuclide examination should not be performed in every high-risk neonate. According to our results, 99mTc-HMPAO brain SPECT might be indicated in those children where noncongruent results were obtained with conventional studies.

Cerebral Palsy↗
PubMed1993

Physiopathological significance of thallium-201 per rectum scintigraphy in liver cirrhosis.

To define the physiopathological significance of 201Tl per rectum scintigraphy, we compared results obtained using this method with direct measurement of inferior mesenteric shunting, portal pressure, liver cellular function as evaluated by the Aminopyrine Breath Test and the size of esophagogastric varices and spleen, constituting, respectively, indirect representation of azygos and splenic shunts. Results indicated that a high correlation exists between the measures of portal systemic shunt estimated by the per rectal method and those obtained by direct administration of the tracer in the inferior mesenteric artery. No correlation was observed between 201Tl per rectal results and portal pressure or with azygos and splenic shunting. Fair correlation was observed with the Aminopyrine Breath Test. This could be explained by the fact that both methods are altered in advanced liver disease. These results suggest that the 201Tl per rectal scintigraphy explores the portal systemic shunt, which depends almost exclusively on the inferior mesenteric territory. While the limited territory explored by the method constitutes, undoubtedly, a limiting factor in detection and quantitation of total portal-systemic shunt, the specific information provided by the test could be useful in defining clinical and biological profiles of cirrhotic patients with inferior mesenteric shunting.

Adult↗
PubMed1993

Prognostic significance of hepatic venous pressure gradient in medically treated alcoholic cirrhosis: comparison to aminopyrine breath test.

In a long-term survival study, we compared the prognostic significance of the hepatic venous pressure gradient and of the aminopyrine breath test (ABT) in 99 alcoholic cirrhotic patients. Thirty patients survived and had a complete follow-up for at least 4 yr. Mean hepatic venous pressure gradient was 19.1 +/- 5.8 mm Hg (range 8-35 mm Hg). Variceal rupture occurred only when the gradient was > or = 12 mm Hg. Variceal bleeding was observed exclusively in patients with large varices. Survival was not influenced by the level of gradient. We used the ABT to classify patients into three groups (group I, ABT > or = 2%; group II, 1% < or = ABT < 2%; and group III, ABT < 1%). Survival was significantly higher in group I than in group II (p < 0.05) or III (p < 0.01), indicating a better prognosis at a residual functional hepatic cellular mass of about 50% of the lower limit of normal value.

Aminopyrine↗