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H Cramer

Publications and source records attributed to H Cramer.

At least 37 records · Page 2Linked to original sources
PubMed1991

Marked improvement of a substance P radioimmunoassay by reduction of 125I-labelled [Tyr8]-substance P prepared by the chloramine-T method with mercaptoethanol and subsequent purification by reversed-phase liquid chromatography.

[Tyr8]-substance P was radiolabelled with 125I by the application of the chloramine-T method. Due to the high oxidative potential of the 125I-chloramine-T system the purified reaction product was converted into a derivative, which presumably had been oxidized to the corresponding sulphoxide at Met11. This conversion was shown by reversed-phase high-performance liquid chromatography after consecutive reduction-oxidation experiments of the freshly prepared radiopeptide. The oxidized derivative exhibited only negligible binding to substance P receptors isolated from rat brain homogenates. However, in contrast, it showed marked cross-reaction to the antibody raised in rabbits against synthetic SP(1-11). The variance in the quantification of identical samples was marked, and the measurement of concentrations in the lower pg/ml range was not sensitive enough to determine levels of substance P-like immunoreactivity in human cerebrospinal fluid. Assay sensitivity could be substantially improved and variance significantly decreased by the use of a radiopeptide, which had been labelled by the chloramine-T method and which had been subsequently reduced with mercaptoethanol and purified by liquid chromatography.

Chloramines↗
PubMed1991

Substance P-like immunoreactivity and somatostatin-like immunoreactivity in the ventricular fluid of patients with chronic pain syndromes.

Substance P-like and somatostatin-like immunoreactivities (SPLI and SLI) were determined in ventricular fluid of patients with chronic pain syndromes and in a comparison group with multiple sclerosis, essential tremor, epilepsy and postanoxic myoclonus. Concentrations of SPLI and SLI were non-significantly decreased by 40% and 33% in chronic pain patients as compared with control patients without pain. There were no differences apparent between subgroups of pain patients (deafferentation pain, neoplasia-induced pain, thalamic pain). High pressure liquid chromatography combined with radioimmunoassay showed marked heterogeneity of SPLI and SLI.

Adult↗
PubMed1991

Adenosine receptor-coupled adenylate cyclase in the caudate nucleus of the rat brain.

5'-(N-Ethylcarboxamido)adenosine (NECA) and N6-[(R)-(phenylisopropyl)]adenosine (PIA) were incubated in an adenylate cyclase assay with a particulate fraction of caudate-putamen tissue of the rat, in order to examine the effect of kainic acid and a 6-hydroxydopamine-induced lesion on adenosine receptor coupled adenylate cyclase in vitro. There was an enhancement of formation of cyclic AMP induced by NECA, that was mediated by A2 adenosine receptors. Phenylisopropyl adenosine also stimulated adenylate cyclase in the striatum, with a maximum increase at 0.1 mM. At smaller concentrations, PIA inhibited the basal activity, which was previously described to be an effect mediated by A1 adenosine receptors. In caudate-putamen tissue from rats receiving a unilateral lesion, induced with kainic acid, basal and maximally NECA- and PIA-stimulated activity of adenylate cyclase was decreased. The maximum stimulatory effects of both substances were also significantly decreased, whereas no change of the inhibitory effect of PIA was observed. After unilateral lesion induced with 6-OHDA, basal and maximally NECA- and PIA-activated adenylate cyclase was increased; however, no inhibitory effect of PIA was seen. These results suggest that A2 adenosine receptor-coupled adenylate cyclase was located on neurones intrinsic to the neostriatum and probably postsynaptic to the dopaminergic input. The A1 adenosine receptors seem to be associated with the nigrostriatal pathway implying a presynaptic localization on dopaminergic afferents. In addition, since after both kainic acid- and 6-OHDA-induced lesions, respectively, in caudate-putamen tissue of the contralateral side, PIA no longer inhibited the activity of adenylate cyclase, contralateral structures also appeared to be involved in the regulation of A1 adenosine receptors.

Adenosine↗
PubMed1991

Ventricular fluid neuropeptides in Parkinson's disease. II. Levels of substance P-like immunoreactivity.

Substance P-like immunoreactivity (SPLI) was determined in cerebrovascular fluid of patients with extrapyramidal motor diseases. Patients with Parkinson's disease (PD) showed a SPLI concentration decreased by 30% compared with patients without extrapyramidal disease. No differences were apparent for patients with dystonia. Fluid obtained from the foramen Monro showed higher SPLI concentrations than fluid from a lateral ventricle, indicating that hypothalamic sources are important for ventricular substance P. Lateral ventricular SPLI was particularly low in parkinsonian patients which raises the possibility of a decreased SPergic activity in basal ganglia occurring in PD.

Adult↗
PubMed1991

Determination of the rate of DNA synthesis of human tumor cells obtained by fine needle aspiration. Comparison of flow cytometry and an immunoperoxidase method for the detection of thymidine analogue incorporation.

Two methods of detecting thymidine analogue incorporation by lymphoma, leukemia and myeloma cells obtained by fine needle aspiration (FNA) are described. In one method, cells which have been incubated with the thymidine analogue iododeoxyuridine (IDURD) were exposed to primary monoclonal anti-IDURD antibody and a fluorescein-labeled linking antibody. The fluorescence of the antibody-labeled cells, which had synthesized DNA and incorporated the analogue, was detected by flow cytometry (FCM). In a second method, the cells that incorporated the analogue were detected on glass slide Cytospin preparations by an immunoperoxidase (IP) technique. The IDURD labeling index (LI), as determined by both FCM and IP staining, was compared to the percentage of cycling (S + G2/M) cells as determined by acridine-orange FCM. The data indicate that the IP method is reliable and correlated strongly with FCM determination of LI, percentage S-phase and lymphoma grade. Given the low cost and wide availability of IP technology, the IP method may be desirable for laboratories wishing to supplement cytology reports with cell cycle data.

Biopsy, Needle↗
PubMed1990

Somatostatin acts through G-proteins on dopaminergic adenylate cyclase in the caudate-putamen of the rat.

Somatostatin was incubated in an adenylate cyclase assay of a particulate fraction of caudate-putamen tissue of the rat in order to examine the effect of the peptide on D-1 receptor coupled adenylate cyclase in vitro. Somatostatin was able to enhance cyclic AMP formation in the presence of guanylylimidodiphosphate and guanosine-triphosphate. In contrast to this, somatostatin inhibited both dopamine and forskolin-stimulated cyclic AMP accumulation. Pertussis toxin and cholera toxin also depressed forskolin-induced stimulation. Somatostatin was found to antagonize these inhibitory effects of pertussis toxin and cholera toxin. The results suggest that somatostatin acts through a stimulatory as well as an inhibitory guanine nucleotide regulatory protein subtype to affect dopaminergic adenylate cyclase activity.

Adenylate Cyclase Toxin↗
PubMed1990

Ventricular fluid neuropeptides in Parkinson's disease. I. Levels and distribution of somatostatin-like immunoreactivity.

We have measured somatostatin-like immunoreactivity SLI in cerebroventricular fluid of patients with Parkinson's disease (PD) and other extrapyramidal disorders with hyperkinesia. Patients with PD showed a significantly lower concentration of SLI when compared with levels in control patients with chronic stable multiple sclerosis or temporal lobe epilepsy. Less markedly decreased levels of SLI were also noted in patients with torsion dystonia. Of two patients with Huntington's disease one showed a high and one a medium concentration of SLI. According to the site of the stereotactic cannula, verified by ventriculopathy, SLI concentrations in CSF specimen obtained from the foramen Monro tended to be higher than in specimen from a supraforaminal level. Of 5 other patients with lateral and third ventricle being accessible during the passage of the stereotactic cannula, 4 showed higher SLI concentrations in the third ventricle compared to the lateral ventricle. High performance liquid chromatographic analysis combined with radioimmunoassay showed molecular heterogeneity of SLI in CSF. The ratio of SST-14 to SST-28 was higher in the third ventricle than in the lateral ventricle.

Adult↗
PubMed1990

Somatostatin-like immunoreactivity in the cerebrospinal fluid of aged patients with Parkinson's disease. The effect of dopatherapy.

Cerebrospinal fluid (CSF) somatostatin concentrations were measured in 35 aged patients with Parkinson's disease (mean age, 79.5 years) and 11 control subjects (mean age, 82.3 years). In patients with Parkinson's disease the levels of somatostatin-like immunoreactivity were lower than in controls (P less than .02); these values were lowest in the untreated group. Somatostatin-like immunoreactivity levels in the CSF tended to increase with treatment but not significantly (P = .11). Somatostatin values were not correlated to age, sex, or duration of the disease. Somatostatin concentrations tended to be lower in more severely affected patients with higher scores on the Hoehn and Yahr (P = .13) and Webster staging scales (P = .13) and lower scores on Mini-Mental State (P = .10), but without statistical significance for these correlations.

Aged↗
PubMed1990

Whole cell preparation of squamous cell carcinoma for cytometric analysis of DNA.

To date, analysis of the DNA content of head and neck squamous cell carcinomas has relied on the homogenation of the entire tissue specimen and subsequent staining and quantitation of the naked nuclei. This methodology does not make allowance for the extremely variable nature of these tumors with respect to their cellular composition. Further, by destroying the cytoplasm and cell membranes, this methodology makes it impossible to distinguish the DNA content of the tumor cells from that of the background stromal and inflammatory cells. The authors present a methodology for the selective exclusion of inflammatory cell infiltrates from the DNA analysis of these tumors. Using this technique, it has been found that exclusion of the inflammatory cells allows the investigator to look more specifically at the malignant cell population. This has been most helpful in those samples in which the tumor cells have been diploid or near-diploid. With this technical refinement, the relationship between DNA ploidy and clinical prognosis may be more accurately assessed.

Aged↗
PubMed1989

[Hyperthermia in cancer research. Historical development, current status of research, future perspectives and differentiation from alternative medical procedures].

Already at the beginning of the 19th century first clinical trials with systemically induced fever were performed on malignant tumors. An intensified research in thermobiology in the sixties of this century gave the rationale for using this modality for cancer treatment. Clinical use of hyperthermia in combination with radiation or chemotherapy begun in the mid of the seventies when a better technique for selective heating of the tumor was used. In the technical development the problem of heating deep-seated tumors was mainly solved. Temperature measurements of the tumor and surrounding tissues are performed with specialized thermometry systems using thin implanted catheters to measure inside the body. 1986 a pilot study was initiated at the Medical Clinic III of the Klinikum Grosshadern to study the effects of regional hyperthermia combined with systemic chemotherapy. This study is aimed on feasibility, toxicity, and tumor response.

Abdominal Neoplasms↗
PubMed1989

Immunoreactive substance P and somatostatin in the cerebrospinal fluid of senile parkinsonian patients.

The concentration of substance-P-like immunoreactivity (SPLI) and somatostatin-like immunoreactivity (SLI) in the lumbar spinal fluid of senile parkinsonian patients (mean age 77.6 +/- 6.7 years) and senile control patients (mean age 83.5 +/- 5.6 years) were determined by specific radioimmunoassays. Mean SPLI and SLI levels in the control group were 8.1 +/- 2.0 (SD) and 32.5 +/- 12.0 fmol/ml, respectively. The mean SPLI levels were not significantly different in the groups. The mean SLI level was significantly lower in the group of patients with Parkinson's disease (19.8 +/- 9.0 fmol/ml). A comparison with results in patients with senile dementia of Alzheimer type (SDAT) shows that, in addition to clinical and pathological correlations, Parkinson's disease of late onset may share a deficit in somatostatinergic neuromodulation with SDAT.

Age Factors↗
PubMed1989

Parathyroid cysts.

Parathyroid cysts are relatively uncommon lesions. Approximately 200 cases have been reported. Despite their location in the region of the thyroid gland, they have not previously been discussed in the otolaryngologic literature. They arise from remnants of the pharyngeal pouch or as a result of cystic degeneration of a parathyroid adenoma. A case of a parathyroid cyst occurring in a 13-year-old female is presented. This is the youngest case ever reported. Fine needle aspiration of an anterior neck mass yielded clear fluid, a finding highly suggestive of a parathyroid cyst. Radioimmunoassay of the fluid demonstrated a high level of parathormone and low level of thyroglobulin concentration, thereby confirming the diagnosis. In this case, which was diagnosed by FNA, the need for a trial of thyroid hormone suppression or hemithyroidectomy was obviated.

Adolescent↗
PubMed1989

Fine-needle aspiration in the management of breast masses.

The exact role of FNA in the diagnosis of palpable breast lesions is still uncertain. False-positive and false-negative cytological diagnoses occur and raise questions regarding the diagnostic utility of FNA as a replacement for open biopsy in many clinical situations. False-positive diagnoses may result from atypical epithelial proliferations, fibroadenomas, or inflammatory lesions. False-negative aspirates may occur because of technical errors, cystic lesions, and underdiagnosis of low grade neoplasms. The triple diagnosis protocol has been suggested as a replacement for open biopsy of palpable breast masses in many clinical situations. Following this algorithm, the results of palpation, mammography, and cytology are combined to guide management. Mammography should precede FNA or follow the cytologic procedure by 2 or more weeks. Patients with a positive triple diagnosis should undergo open biopsy or confirmatory intraoperative frozen section. Positive FNA results would be useful for preoperative counselling as well as serving as a diagnostic procedure for clinically suspicious lesions in patients wishing a confirmatory test before open biopsy is performed. Patients with discordant triplet results should be referred for open biopsy. The management of patients with negative triplet results is less clear. From the available data, it appears that approximately 2 percent of patients with negative triplet results have carcinoma. Based on these results, we cannot recommend replacing open biopsy by the triple diagnosis method in most patients with a persistent dominant mass. In most cases, a biopsy is indicated. Surgeons, who plan to follow a breast mass with clinical examination, may be able to reduce their false-negative rate by performing FNA. Further study is necessary to establish the best way to use FNA in the diagnosis of breast carcinoma, to determine the cost effectiveness of the triple diagnosis method as a substitute for open biopsy, and to assess the utility of aspiration cytology in the mammographically directed diagnosis of nonpalpable breast lesions.

Adenofibroma↗
PubMed1988

Cerebrospinal fluid immunoreactive substance P and somatostatin in neurological patients with peripheral and spinal cord disease.

We have measured substance P-like (SPLI) and somatostatin-like (SLI) immunoreactivities in cerebrospinal fluid of 49 patients with peripheral (polyneuropathy, lumboischialgia) and spinal cord disease and in 16 control patients. The patient groups showed significantly higher CSF SPLI levels than controls while the mean SLI levels were unchanged. Fractionated sampling of CSF (total volume 30 ml) in 20 patients with various neurological diseases showed no significant differences between early and late fractions for SLI. In contrast, lumbar-cisternal concentration gradients were negative for SPLI, total protein and IgG, and positive for the dopamine metabolite homovanillic acid and the serotonin metabolite 5-hydroxyindolacetic acid. This suggests that SPLI may be released into the lumbar CSF from lower levels of the neuraxis, presumably the spinal cord and spinal ganglia, whereas SLI stems from diffuse CSF secretion without spinal preponderance.

Adult↗
PubMed1987

Dopamine and somatostatin modulated adenylate cyclase activity in the rat caudate-putamen following unilateral cortical ablation.

Dopamine and somatostatin-14 (SRIF) were incubated with a membrane fraction of rat caudate-putamen (CP) tissue in an adenylate cyclase assay in order to examine the D-1-receptor coupled adenylate cyclase activity 5 days and 3 weeks after unilateral ablation of the left frontal and lateral cortex. Five days after decortication the ipsilateral basal and dopamine stimulated adenylate cyclase activity was increased by about 30% compared to that of the contralateral side. Three weeks after decortication no significant difference could be seen. On either side basal and dopamine stimulated adenylate cyclase activity was not significantly decreased compared to sham operated controls. Somatostatin (10(-7) mol/l) reduced basal adenylate cyclase activity of the ipsilateral CP five days following lesioning and reduced the maximal stimulation induced by dopamine. The effects of somatostatin were most marked in the absence and at low concentrations of dopamine (10(-7)-10(-6) mol/l). The effects of somatostatin in the lesioned CP were no longer apparent three weeks following surgery. These results do not favour a presynaptic localization of D-1-receptors on cortico-striate projection fibers and suggest that somatostatin is involved in the interaction of the cortico-striate and nigro-striatal projection systems and may play a role in the regulation of D-1-receptor linked adenylate cyclase.

Adenylyl Cyclases↗
PubMed1987

Comparison of DSIP- (delta sleep-inducing peptide) and P-DSIP-like (phosphorylated) immunoreactivity in cerebrospinal fluid of patients with senile dementia of Alzheimer type, multi-infarct syndrome, communicating hydrocephalus and Parkinson's disease.

The concentrations of delta sleep-inducing peptide (DSIP)-like (DSIP-LI) and P-DSIP-like (phosphorylated, Ser7) immunoreactivity (P-DSIP-LI) were measured by specific radioimmunoassay in the cerebrospinal fluid (CSF) of patients with senile dementia of the Alzheimer type [SDAT, subdivided into early (S1), middle (S2) and late dementia (S3)], multi-infarct dementia (MD), Parkinson's disease (PD), vascular disease (VD) and communicating hydrocephalus (H), as well as in control patients (C1, C2). Mean DSIP-LI and P-DSIP-LI concentrations were found to be significantly higher in the elderly control group (C1, mean age 83 +/- 5 years) than in the middle-aged control group (C2, mean age 40 +/- 16 years). DSIP-LI and P-DSIP-LI were positively correlated with age in both control groups. Significant decreases of DSIP-LI compared with age-matched controls (C1) were observed for S2, S3, MD, PD, VD and H. In contrast, no significant differences corresponding to pathology were found for P-DSIP-LI.

Adult↗