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J Andreas

Publications and source records attributed to J Andreas.

At least 19 recordsLinked to original sources
PubMed1999

Occupancy of striatal D(2)-like dopamine receptors after treatment with the sigma ligand EMD 57445, a putative atypical antipsychotic.

RATIONALE: EMD 57445 (panamesine) is a high affinity sigma ligand with the profile of an atypical antipsychotic in animal studies. It has been reported recently to have antipsychotic activity in schizophrenia. However, its metabolite, EMD 59983, binds also to D(2) and D(3) dopamine (DA) receptors. OBJECTIVES: The aim of this study was to test, using single photon emission computed tomography (SPECT) and [(123)I]iodobenzamide (IBZM) as the radiotracer, whether EMD 59983 would pass the blood-brain barrier and to what extent it would contribute to the effects of EMD 57445 in schizophrenia. METHODS: Two IBZM SPECT-scans were performed in five neuroleptic-free schizophrenic patients (DSM IV), one before and one after treatment with 60 mg panamesine daily for a treatment duration of 12-26 days. RESULTS: A high occupancy of striatal D(2)-like DA receptors similar to that induced by typical neuroleptics was observed in all patients treated with EMD 57445. CONCLUSIONS: Our results suggest that a possible antipsychotic activity of EMD 57445 in schizophrenia is not necessarily attributable to its affinity for sigma receptors, but could be simply due to the potent antidopaminergic effects of EMD 59983, its main metabolite.

Adult↗
PubMed1999

[Spontaneous intracranial hypotension syndrome. Clinical, neuroradiological and cerebrospinal fluid findings].

We report 11 patients with orthostatic headache due to spontaneous intracranial hypotension. Nausea (3 patients) and abducens palsy (2 patients) were the main additional symptoms. Ten patients had CSF pleocytosis (6 to 43 white cells/microliter) and/or increased protein (581 to 1668 mg/l). CT and/or MRI documented bifrontal accentuated subdural hygromas and hematomas in 5 patients. MRI also documented diffuse meningeal gadolinium enhancement in all 4 patients examined, and descent of the brain in one. Cisternography was done in 9 patients and revealed a decreased or absent activity over the convexities and early detection of the tracer in the bladder in all, and a CSF leak at the cervicothoracal junction in 2 patients. Most patients improved with bed rest, increased fluid intake (oral or intravenous), steroids, and/or epidural blood patch. Subdural hematomas increased in 2 patients and have to be drained. Spontaneous intracranial hypotension is due to a CSF leak followed by decreased CSF volume and hydrostatic CSF pressure changes. The locations of the leaks are mainly cervical or at the cervicothoracal junction. MRI always documents diffuse meningeal gadolinium enhancement. Treatment of choice is an epidural blood patch. Surgical treatment may be needed in patients with subdural hematomas or meningeal diverticula. Prognosis is typically good, but subdural hematomas may occasionally lead to an increased intracranial pressure.

Adult↗
PubMed1999

[99mTc-MIBI-scintigraphy before parathyroid surgery?].

AIM: In a non prospective study the value of preoperative parathyroid imaging with 99mTc-MIBI-scintigraphy was evaluated. PATIENTS AND METHODS: From August 1, 1987 to December 15, 1997 453 patients were operated on for hyperparathyroidism. Preoperatively 116 patients underwent 99mTc-MIBI-scanning, which had been carried out by several institutes. RESULTS: Primary hyperparathyroidism. Sensitivity of MIBI-scintigraphy in solitary parathyroid adenoma (n = 48) and first-time cervical exploration was 54% (25 true positive scans) and overall sensitivity was 50% (25 true positive scans in 53 patients). In 6 patients with persistence or recurrence of primary hyperparathyroidism MIBI-scintigraphy was true positive (sensitivity 100%). Neither the volume nor the weight of the adenomas influenced the result of MIBI-scanning. There was no correlation between preoperative serum concentrations of calcium and intact parathormone and sensitivity of MIBI-scintigraphy. Renal hyperparathyroidism. Before first-time cervical exploration sensitivity of MIBI-scintigraphy (n = 40) for detecting all abnormal parathyroid glands in the presence of diffuse hyperplasia yielded only 10%. In 5 of 7 patients, who underwent reexplorations of the neck or mediastinum for persistence or recurrence of renal hyperparathyroidism MIBI-scintigraphy was true positive (sensitivity 71%). The sensitivity for detection of hyperplastic parathyroid glands correlated with the weight as well as with the volume of the glands (p < 0.001). The weight of imaged glands ranged from 0.21 to 9.76 g, median 1.27 g and their median volume was 1.12 ml (range: 0.04-15.63 ml). For non imaged glands a median weight of 0.49 g and a median volume of 0.3 ml (ranges: 0.03-10.34 g, 0.009-9.8 ml, respectively) could be estimated. CONCLUSIONS: First-time cervical exploration for hyperparathyroidism can be carried out with a high success rate and without any preoperative localization study. Before recurrent parathyroid surgery we recommend 99mTc-MIBI-scintigraphy because of its > 90% sensitivity.

Humans↗
PubMed1999

[Somatostatin receptor status in non-medullary thyroid carcinoma].

AIM: Recent in-vitro and in-vivo studies demonstrated a somatostatin receptor expression in some non-medullary thyroid carcinomas. In this study we investigated the somatostatin receptor status for this particular tumor entity in a larger patient group. SUBJECT AND METHODS: We compared 131-iodine with 111-In-pentetreotide scans in 24 patients with metastasizing, non-medullary thyroid cancer. The findings were correlated with other imaging modalities. Additionally, we performed receptor autoradiography in one patient, octreotide therapy in another patient and administration of 90-Y- and 111-In-DOTATOC in 2 consecutive patients. RESULTS: In the 15 patients with papillary or follicular carcinoma, 111-In-pentetreotide was inferior to 131-I in 8/15, equal in 1/15, and superior in 6/15 patients. In 8/9 of the patients with Hürthle cell carcinoma, metastases showed a 111-In-pentetreotide accumulation of various intensity, while 131-iodine scans were negative except for one patient. 111-In-pentetreotide was equal or superior compared to 201-Tl or 99m-Tc-sestamibi, but for the most part inferior in comparison with 18-F-FDG-PET. The findings of 111-In-pentetreotide scintigraphy correlated well with the receptor autoradiography and the accumulation of DOTATOC, but not with the therapeutic effect of "cold" octreotide on the thyroid cancer metastases. CONCLUSIONS: Several metastases of papillary and follicular carcinoma, and the majority of Hürthle cell cancer metastases can express somatostatin receptors. 111-In-pentetreotide scintigraphy is a promising tool for localization of metastases especially in Hürthle cell cancer or if PET is not available, and may be useful for selection of possible candidates, if therapeutic effective beta-emitting somatostatin analogues will be available for routine application.

Adenocarcinoma, Follicular↗
PubMed1998

[Prognostic value of e-cadherin in papillary thyroid carcinoma].

The prognostic significance of e-cadherin in papillary thyroid carcinoma was evaluated in a retrospective study. From September 1985 to December 1996, 113 patients underwent surgery for papillary thyroid carcinoma. Seventy-eight formalin-fixed, paraffin-embedded tissue samples were available for immunohistochemical analysis of e-cadherin expression. In 74 of these 78 patients the postoperative course is known for 2 months to 35.2 years (median 3.6 years, mean: 4.9 +/- 4.8 years). Reduced or negative e-cadherin expression (< or = 20%) was associated with advanced T categories of the primary tumours and higher rates of synchronous lymph node involvement and distant metastasis. During follow-up in this group of patients locoregional tumour recurrence occurred more frequently and survival was shorter than in patients with tumours which exhibited e-cadherin expression of > 20%. Statistical analysis revealed e-cadherin expression (< or = 20%/ > 20%), synchronous distant metastasis (M0/pM1, cM1) and radicality of resection (R0/R1, 2) as significant risk factors for survival. Our findings provide evidence that e-cadherin is a prognostic factor in papillary thyroid carcinoma.

Adult↗
PubMed1998

Long-term metabolic effects in patients with urinary diversion.

The use of intestinal segments in genitourinary reconstruction could influence vitamin metabolism and affect the skeletal bone and its mineral content in the long term. In 137 patients, serum levels of the vitamins A, B1, B2, B6, B12, D, and E and of folic acid, bile acid, and ammonia as well as levels of intracorpuscular vitamin B12 and folic acid were examined and a red blood cell count was performed. The patients were divided into three groups (< or = 2 years, > 2 to < or = 4 years, and > 4 years after surgery) as well as into children and adults. In addition, bone mineral density (dual-photon absorptiometry) was measured in 25 patients. Of these, 16 patients were approximately 16.8 years s/p rectal reservoir, 6 were approximately 20.5 years s/p colonic conduit, two were 6 and 8 years s/p ileocecal pouch, and one adolescent was 5 years s/p ileal bladder augmentation. In all patients the levels of vitamins A, B1, B2, B6, D, and E and of folic acid, bile acid, and ammonia as well as the red blood cell count were within normal ranges. In children (n = 51) there was no significant drop in vitamin B12 levels after the operation. In adults (n = 86), serum vitamin B12 levels dropped significantly from 402 +/- 182 ng/l during the first 2 years after the operation to 292 +/- 204 ng/l after the 4th year (normal range 240-1,100 ng/l). No significant increase in the intracorpuscular vitamin B12 level was observed during the same period. The bone mineral density was normal in all 25 patients with different types of urinary diversion. In addition to regular examination (sonography, creatinine levels, and base excess), vitamin B12 levels should be determined at 4 years after urinary diversion. It remains unclear whether substitution is necessary. However, substitution is easy to achieve and cheaper than the regular determination of vitamin B12. No decrease in bone mineral content was seen in the long-term follow-up with early correction of the base excess (below -2.5).

Adult↗
PubMed1998

Effect of long-term treatment with GH on bone metabolism, bone mineral density and bone elasticity in GH-deficient adults.

OBJECTIVE: Adults with GH deficiency (GHD) commonly have subnormal bone mineral density (BMD), and have been reported to have an increased risk of fractures. It has been suggested that GH replacement therapy may have beneficial effects on bone in such patients. The aim of this study was to investigate the effects of long-term GH replacement therapy on bone metabolism, BMD and bone elasticity in adults with GHD. DESIGN: At the start of the study, 20 adults with GHD were randomized to receive either GH, 0.25 IU/kg/week (the 'GH group') or placebo (the 'placebo group'). After 6 months, patients in the placebo group were switched to GH therapy, and all patients received GH for a further 42 months. PATIENTS: Of the 20 patients included in the study, 11 were male and nine were female. Mean age at the start of the study was 42.5 +/- 10.1 years. All patients had been GH-deficient for at least 2 years before the start of the study. MEASUREMENTS: Rates of bone resorption and formation were assessed by measuring serum levels of type I collagen carboxyterminal cross-linked telopeptide (ICTP) and carboxyterminal propeptide of type I procollagen (PICP), respectively. BMD was measured at the lumbar spine by dual-photon absorptiometry (DPA) and at the non-dominant forearm by single-photon absorptiometry (SPA). Bone elasticity was assessed by measuring apparent phalangeal ultrasound transmission velocity (APU). RESULTS: The main results in the GH group were as follows. The rate of bone resorption increased significantly during the first 6 months of treatment and remained significantly elevated above its baseline level thereafter. The rate of bone formation also rose during the first 6 months of treatment and remained elevated thereafter, but was significantly higher than at baseline only after 24 months of treatment. At both sites measured, BMD was subnormal at baseline, decreased during the first 6 months of treatment, and increased progressively for the rest of the study, eventually rising well above its baseline level. Bone elasticity decreased during the first 6 months of treatment, but had returned to its baseline level after 24 months. CONCLUSIONS: Our results support previous findings that BMD is subnormal in adults with GHD, that GH replacement therapy can stimulate bone turnover in such adults and that, in the long term, such stimulation results in a significant increase in BMD. In addition they show, for the first time, that BMD may continue to rise even after GH replacement therapy has been administered for 4 years, and indicate that bone elasticity is not adversely affected by long-term GH therapy.

Absorptiometry, Photon↗
PubMed1998

Whole-body potassium and bone mineral density up to 30 years after urinary diversion.

OBJECTIVES: To evaluate the long-term effects of different types of urinary diversion on skeletal bone density and whole-body potassium content in patients with an early correction of base excess (< -2.5). PATIENTS AND METHODS: The early correction of base excess (< -2.5) is one of the principles of the treatment of patients undergoing urinary diversion at our institution. In 27 patients with urinary diversion, bone mineral density (assessed by dual-photon absorptiometry), whole-body potassium, electrolyte and creatinine levels were determined, and capillary blood gas analysed. The mean time since surgery was 16.8 years in 16 patients with a rectal reservoir, 20.5 years in six patients with a colonic conduit, 7.8 years in four patients with an ileocaecal pouch and 5 years in one adolescent with an ileal bladder augmentation. RESULTS: Bone mineral density was normal in 25 of the 27 patients; no exact measurement was possible in the remaining two. The whole-body potassium content was reduced in eight of the 27 patients (three with a conduit, two with a rectal reservoir, two with an ileocaecal pouch and one with ileal augmentation). In four of these eight patients the base excess was < -2.5 (-2.7 to -5). Of the other four, two had no regular testing of their base balance and two were obese. The electrolytes were within the normal ranges. None of the patients had hyperchloraemic metabolic acidosis. CONCLUSION: With early correction of the base excess (< -2.5), there was no decrease in bone mineral density and no hyperchloraemic acidosis. There was no significant difference between the different types of urinary diversion. There seems to be a relationship between low base excess and decreased whole-body potassium.

Adolescent↗
PubMed1997

Bone mineral density and bone metabolism in diabetes mellitus.

The effect of diabetes mellitus on bone metabolism and bone mineral density is discussed controversially. Diabetes mellitus due to an autoimmune process seems to be associated with low turnover osteopenia either in the animal model or in children and adolescents. A number of factors are discussed as being involved, but in this age group clinical symptoms are missing. Adult patients of either sex with IDDM show a reduced bone mineral density when measured at peripheral sites such as the distal forearm or the femoral neck, diabetic complications such as neuropathy and microangiopathy seem to pronounce the deficit of bone mass. In these patients, osteopenia is accompanied by a high turnover situation of bone metabolism, possibly due to microvascular complications. In contrast, patients with NIDDM and here especially overweight women have a normal or even increased bone mineral density. Up to now, there is no convincing evidence for an increased incidence of osteoporotic fractures in diabetic patients. Systemic diabetic osteopenia therefore does not seem to be of great epidemiological relevance.

Animals↗
PubMed1997

[Automatic setting of the contrast range of whole body scintigrams using a histogram method].

AIM: To get standardised results on the display of whole body scintigrams regarding an optimal contrast setting (using linear scaling), an algorithm was developed, which can be used for an automatic setting of an upper intensity truncation value. METHODS: From the integral of the gray level histogram of 30 randomly selected whole body images upper threshold values LA were defined, where a certain area percentage A (80% < or = A < or = 99.5%) of all pixels with intensity > 0 are contained in the intensity range. Independently an interactive upper level Lvis of the contrast range was determined by two observers to get an optimal visual appearance of the image. RESULTS: For the threshold levels with an area percentage A of 92% ... 98% (L92 ... L98) a very close linear correlation (r > 0.9) was found to the visual levels. Levels resulting to area percentages A < 92% or A > 98% correlated worse to the interactive values. Based on our results we propose as a good definition for an upper threshold on whole body scintigrams with dual intensity ranges: Range 1 (high activities): Upper threshold = min (2.5 x L95, 100%), Range 2 (low activities): Upper threshold = min (1.25 x L95, 100%). CONCLUSION: The procedure is well suited for an automatic definition of the contrast settings of whole body scintigrams. It can be implemented easily; its use gives a substantial contribution to the standardisation of the documentation of scintigrams.

Automation↗
PubMed1996

Dysarthria and lacunar stroke: pathophysiologic aspects.

We investigated the supranuclear tracts involved in speech production in 8 patients with dysarthria associated with a single lacunar stroke. Magnetic resonance imaging revealed the lesion site in 7 out of 8 patients. We tested corticobulbar tract function using transcranial magnetic stimulation and demonstrated impairment of the corticolingual projections in all the patients and in 5 patients impairment of the corticofacial projections. Sensory function in the oral cavity was impaired in 1 out of 8 patients. 99mTc hexamethyl-propylene amine oxime-single-photon emission computerized tomography (HMPAO-SPECT) imaging, performed in 5 patients, showed cerebellar diaschisis in 1, suggesting additional cerebropontocerebellar tract impairment. Dysarthria observed in the 2 patients with impaired sensation in the oral cavity or with cerebellar diaschisis did not differ from the dysarthria found in the other patients. We conclude that interruption of the corticolingual pathways to the tongue is crucial in the pathogenesis of dysarthria following extracerebellar lacunar stroke.

Aged↗
PubMed1995

Peripheral osteopenia in adult patients with insulin-dependent diabetes mellitus.

Alterations in bone metabolism in diabetes mellitus is a topic of special interest. Bone blood flow is increased in the distal limb of diabetic patients, which is believed to increase osteoclastic activity. We measure bone mineral density using dual-photon absorptiometry in the distal lower limb, the femoral neck, and the lumbar spine in 41 IDDM patients and in 30 control persons. In the diabetic group there was a 10% reduction of bone mineral density in the femoral neck (p < 0.01) and a 12% reduction in the distal limb (p < 0.001) compared with the control group. No significant difference was found in the lumbar spine (p = 0.22). Our data yield incidence for peripheral osteopenia in IDDM-patients, independent of any systemic bone disease such as osteoporosis. A link between decreased bone mineral density and diabetic neuropathy has been observed for the femoral neck (p < 0.001), but not for the distal limb or axial skeleton. Whether there is a common aetiological link or a casual connection between diabetic neuropathy and bone mineral density has still to be determined.

Absorptiometry, Photon↗
PubMed1993

[99mTc-MAG3-kidney function scintigraphy without and with captopril in the diagnosis of renovascular hypertension].

In this study, the diagnostic value of renal function scintigraphy performed both without and with ACE inhibition has been evaluated using the new radiopharmaceutical 99mTc-MAG3. In cases of decompensated renal artery stenoses, the typical scan finding with this tubular excreted agent was shown to be a distinct parenchymal nuclide retention in combination with a delayed appearance of the radiotracer in the pelvic system. Using this criterion in 43 patients with suspected renovascular hypertension, sensitivity and specificity were 89 and 88%, respectively. Bilateral positive findings were non-specific; excluding them from the study, specificity increased to 100%. In renal insufficiency, captopril scans seem to be of reduced diagnostic value. Summarising our experiences, renal function scintigraphy using 99mTc-MAG3 without and with captopril was proved to be a reliable non-invasive method to detect or exclude haemodynamically relevant renal artery stenosis.

Captopril↗