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H Cramer

Publications and source records attributed to H Cramer.

At least 91 records · Page 5Linked to original sources

Endocrine profile of a long-acting somatostatin derivative SMS 201-995. Study in normal volunteers following subcutaneous administration.

The pharmacokinetics and the endocrine profile of a new low molecular somatostatin derivative, SMS 201-995, were investigated in a group of 35 normal subjects. Clearance studies (n = 6) for this peptide showed a prolonged half-life in plasma, 113 min, following single sc injections of 50 or 100 micrograms. Arginine stimulation tests (n = 6) were conducted immediately and 180 min after sc injection of 50 micrograms of SMS 201-995. The stimulatory effect of arginine on GH and insulin was counteracted by the peptide at the P less than 0.001 and P less than 0.02 significance level, respectively. Delayed arginine stimulation revealed a persistent blockade of the GH release (P less than 0.02), whereas a recovery of the insulin response was observed. Plasma glucagon increments following a standard protein meal (n = 10) were significantly (P less than 0.001) inhibited by previous sc injection of 50 micrograms of SMS 202-995. Pretreatment with 50 and 100 micrograms of SMS 202-995 sc (n = 9) inhibited (P less than 0.001) the stimulatory effect of TRH (200 micrograms iv) on TSH without modifying basal levels. The injection of 100 micrograms/h during sleep completely abolished the nocturnal GH peak in 4 volunteers. No rebound rise after decline of the suppressive action on GH was recorded in any of the trials. Safety chemistries and blood coagulation studies remained normal and no side-effects or untoward reactions were recorded throughout the investigation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Ventricular somatostatin-like immunoreactivity in patients with basal ganglia disease.

The concentrations of somatostatin-like immunoreactivity (SLI) in lateral ventricular fluid of patients with extrapyramidal motor disease were determined by specific radio-immunoassay. Mean SLI levels were significantly lower in patients with Parkinson's disease (mean +/- SEM); 42.9 +/- 2.9 fmol/ml) and in patients with dystonic syndromes (39.4 +/- 3.2) than in patients with benign essential tremor (65.3 +/- 9.7). The lowest levels were found in patients with athetosis (34.7 +/- 5.4). In parkinsonian patients somatostatin levels correlated with the degree of akinesia, rigidity and autonomic disturbances.

Adult↗

Somatostatin-like immunoreactivity and substance-P-like immunoreactivity in the CSF of patients with senile dementia of Alzheimer type, multi-infarct syndrome and communicating hydrocephalus.

The concentrations of somatostatin-like immunoreactivity (SLI) and substance-P-like immunoreactivity (SPLI) in lumbar spinal fluid of patients with senile dementia of the Alzheimer type (SDAT), multi-infarct syndrome, communicating hydrocephalus and control patients were determined by specific radio-immunoassay. Mean SLI and SPLI levels were significantly lower in an aged control patient group (mean age 83.5 +/- 5.6 years) than in an adult control patient group (mean age 30.8 +/- 10 years). In the latter group SPLI levels correlated negatively with age. Mean SLI levels decreased with deterioration in SDAT patients by up to 33% in late dementia. SPLI correlated with SLI in SDAT patients but was decreased significantly only in late dementia patients. Moderate and insignificant decreases of SLI were observed in patients with multi-infarct syndrome or communicating hydrocephalus. Analysis of SLI by gel-permeation chromatography revealed molecular heterogeneity of SLI. At least four peaks of SLI were eluted, two of which had apparent molecular weights of about 10,000 and 15,500, possibly representing somatostatin precursors. The ratio of SRIF to SLI of higher molecular weight was increased in patients with dementia compared to control patients.

Aged↗

Haloperidol increases the cerebrospinal fluid concentrations of cyclic GMP in schizophrenic patients.

The concentration of cyclic guanosine 3',5' monophosphate (cGMP) in cerebrospinal fluid (CSF) is supposed to reflect central cholinergic activity. Earlier findings in the literature of decreased CSF concentrations of cGMP in drug-free schizophrenic patients accorded with the hypothesis of a cholinergic-dopaminergic imbalance in schizophrenia, with a relative dominance of dopaminergic activity. In the present study, treatment with haloperidol for 3 weeks significantly increased the CSF concentration of cGMP in 14 of 18 schizophrenics. This finding suggests that haloperidol and possibly other antipsychotic drugs might restore the cholinergic-dopaminergic balance in schizophrenia through central cholinergic stimulation in addition to the blockade of dopaminergic receptors.

Adult↗

Cerebral gigantism associated with jaw cyst basal cell naevoid syndrome in two families.

We report 9 subjects from 2 families with the syndrome of cerebral gigantism, seven of the patients also had jaw cyst basal cell naevoid syndrome. Neurological, radiological, somatic and biochemical features of this hitherto unreported association are described. Neurological symptoms included mild hydrocephalus, ventricular malformation, cerebellar syndrome, intracranial calcification, oculomotor disturbances, EEG abnormalities and rarely, mild peripheral nervous disorders. A disturbance of calcium metabolism appears to be a prominent feature of the genetically determined nonprogressive syndrome.

Adolescent↗

The effects of probenecid on cyclic adenosine 3',5'-monophosphate levels in cerebrospinal fluid and on brain phosphodiesterase activity in the rat.

In rats, probenecid exhibits a dose-dependent increase in the concentration of cyclic adenosine 3',5'-monophosphate (cAMP) in cisternal cerebrospinal fluid (CSF). Maximal accumulation is reached 2 h after IP administration at a dosage of 150 mg/kg body weight. Serum levels of cAMP are unchanged after 200 mg/kg probenecid. In vitro investigations show an inhibitory effect of probenecid on the uptake of cAMP into the isolated choroid plexus of the rabbit. A non-competitive inhibition of probenecid on a high affinity fraction of cyclic nucleotide phosphodiesterase from rat brain homogenates is demonstrated with an inhibitor constant of 3.4 X 10(-3M. The results appear to validate the "probenecid test" for cAMP in clinical diagnostics.

Animals↗

Low CSF concentrations of cyclic GMP in schizophrenia.

Increasing evidence suggests that the concentrations of cyclic guanosine 3'5'-monophosphate (cGMP) in the cerebrospinal fluid (CSF) may reflect central cholinergic activity. When the concentrations of this nucleotide in the CSF from 28 schizophrenic patients (13 without and 15 with neuroleptic treatment) and 16 psychiatrically healthy controls was determined the schizophrenics showed significantly lower CSF levels of cGMP as compared to controls. As dopamine and homovanillic acid concentrations were not altered in these CSF samples, this finding of reduced cGMP suggests a cholinergic-dopaminergic imbalance in schizophrenia, with a reduction of the former and consequently a relative dominance of the latter.

Adult↗

Huntington's disease - imbalance of free amino acids in the cerebrospinal fluid of patients and offspring at-risk.

A total of 27 different amino acids were determined in the fasting, morning lumbar CSF of 12 patients with Huntington's Disease (HD), 8 at-risk offspring and 16 non-choreic control patients. A significant (P less than 0.001) decrease was observed for asparagine, isoleucine, leucine, phenylalanine, histidine, arginine, alpha-aminoadipic acid and homocarnosine in patients with HD compared to the non-choreic controls. Only tyrosine was increased in HD. These alterations were to an extent more pronounced in 5 neurophysiologically conspicuous offspring. The alterations suggest that amino acid imbalance is an early metabolic disturbance in HD.

Amino Acids↗

Somatostatin-like immunoreactivity in the cerebrospinal fluid of neurological patients.

Using a specific radioimmunoassay we have measured somatostatin-like immunoreactivity (SLIR) of CSF in patients with brain atrophy, spinal spasticity, seizures, brain tumors and inflammatory disorders. Patients with marked brain atrophy had significantly decreased somatostatin levels in CSF. In patients with spinal spasticity significantly higher levels were observed. Seizure patients had reduced levels but the difference was not significant. In patients with inflammatory disorders and malignant brain tumors SLIR levels were significantly elevated but not in patients with benign brain tumors. A possible pathophysiologic meaning of SLIR in spasticity and seizures is discussed. The altered levels in brain atrophy, tumors and inflammatory disorders are probably indirect signs of altered somatostatin turnover or increased somatostatin leakage from damaged CNS.

Adolescent↗

Cyclic nucleotides in cerebrospinal fluid of patients with intracranial and spinal tumors.

Since the cyclic nucleotides (CN) adenosine 3',5'-monophosphate (cAMP) and guanoside 3',5'-monophosphate (cGMP) are involved in the regulation of cell proliferation and tumor growth in vitro, a study was made of the levels of these compounds in the lumbar cerebrospinal fluid (CSF) of 20 patients with intracranial and spinal tumors. In the presence of benign or malignant intracranial tumors there was a slight and not significant decrease of cAMP as well as cGMP levels in the CSF, as compared to control patients. While there was no significant correlation between the levels of the two CN in controls, there was a positive correlation in tumor patients. Total protein content and cAMP were negatively correlated in malignant intracranial tumors. Possible influences of tumor growth and intracranial pressure increases on CN levels are discussed. In spinal tumor patients normal CN levels were observed. However, in a patient with meningeal sarcoma an extremely marked elevation of cAMP occurred in parallel with the extension of the tumor to the spinal meningeal space, suggesting massive secretion of cAMP from the tumor cells.

Adolescent↗

Changes in cerebrospinal fluid cyclic nucleotides in alcohol-dependent patients suffering from delirium tremens.

In eight patients with a history of alcoholism (on average 9 years), cyclic 3',5'-monophosphate (AMP) and cyclic 3',5'-monophosphate (GMP) were determined in CSF in the acute untreated phase of delirium tremens and at 2 weeks later when clinical symptoms had vanished. Before the second lumbar puncture a drug-free period of 1 week had existed. The results were compared with an age- and sex-matched neurological control group. CSF cyclic AMP concentrations were markedly reduced by 62% (p less than 0.005) in the acute state of delirium tremens and remained at the same level 2 weeks later; cyclic GMP concentrations were increased by 37% (p = 0.05) and showed a small further increase (p less than 0.05) at the second lumbar puncture. A negative correlation existed between age and cyclic AMP content of CSF (r = -0.756; p less than 0.05) in the patients group. The data indicate that the earlier observed increase in norepinephrine turnover in the acute state of delirium tremens (Athen et al., 1977) seems not to induce an increase of cyclic AMP content in CSF.

Adult↗

Leg function after radiotherapy for Ewing's sarcoma.

Twenty-nine patients with Ewing's sarcoma of the lower extremity who survived for two or more years following therapy (5000 rad locally and systemic chemotherapy) were studied to assess functional status of the affected leg. Twenty-two of twenty-nine were alive and were reexamined; the deceased patients were evaluated by record review. Twenty-two of the twenty-nine had serial radiographs, which were reviewed to assess growth change induced by radiation. The living patients were divided on the basis of clinical examination into four functional groups with Group I comprising patients with minor functional limitations and leg length discrepancy 1.5 cm or less. Group II patients had moderate functional limitations with 2.5-cm leg-length discrepancy or less. Group III patients had severe functional limitations with up to 4-cm leg length discrepancy. Group IV patients had severe complications, sufficient enough to warrant amputation. Thirteen of twenty-two patients were classified as functional Group I, five as Group II, three as Group III, and one as Group IV. Radiographic changes in growing bone did not correlate with functional results. Although a femoral fracture and an age less than 16 years at diagnosis were found to be less favorable prognostic factors for the functional treatment result, these results show that neither femoral location nor young age justify primary amputation for Ewing's sarcoma of the lower leg extremity.

Adolescent↗

Huntington's chorea-- measurements of somatostatin, substance P and cyclic nucleotides in the cerebrospinal fluid.

Somatostatin, substance P, cyclic AMP and cyclic GMP were determined in the cerebrospinal fluid of patients with Huntington's disease, in first generation relatives of choreic patients and in neurological control patients. Substance P levels were not significantly altered, but somatostatin levels were markedly decreased both in affected patients and symptom-free offspring. Cyclic AMP was decreased only in patients with advanced stages of the disease while cyclic GMP was normal. Evidence is discussed which may support a role of somatostatin deficiency in the pathophysiology of chorea.

Adult↗

[Effects of carbamazepine on EEG. Neuroendocrinological and psychometric examinations (author's transl)].

The effects of carbamazepine on EEG, sleep-related release of growth hormone and prolactin, and on psychometric parameters were studied in ten healthy volunteers under controlled double-blind cross-over conditions. Acute application of 300 and 600 mg Tegretal resulted in constant blood levels around 3.0 and 5.5 microgram/ml respectively during the test periods of 5 and 7 h. Computerized EEG analysis according to Hjorth, revealed an occipital increase of amplitude and a decrease of mean frequency, but a frontal increase of frequency, a pattern similar to that of the tricyclic antidepressants. The polygraphic sleep pattern showed a significant decrease of sleep latency after 600 mg carbamazepine without changes of other sleep parameters. The sleep-related release of growth hormone after 600 mg carbamazepine showed a faster increase during the first sleep cycle; the profile of prolactin release, however, and the overall nocturnal secretion of both hormones were not affected. After 300 mg carbamazepine the psychometric tests revealed no significant effects on performance, but reflected an improvement of mood on self rating scales.

Adult↗