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Biomedical subjects

R Arnold

Publications and source records attributed to R Arnold.

At least 91 records · Page 5Linked to original sources

Treatment of endocrine gastroenteropancreatic tumors with somatostatin analogues.

Somatostatin is a hormone that regulates the function of several exocrine and endocrine glands. The peptide mediates its actions via five different receptors. These proteins are expressed in a tissue-specific manner. Somatostatin receptors are also present in neuroendocrine gastroenteropancreatic tumors. Two long-acting somatostatin analogues, octreotide and lanreotide, are recognized by the receptor subtypes 2 and 5. Excessive hormone secretion in carcinoid syndrome can be controlled by these drugs. In addition, at least a subgroup of patients with carcinoid syndromes respond with delayed tumor growth during octreotide therapy. In the future, the availability of the somatostatin receptor cDNAs will allow the development of specific and even more potent receptor analogues.

Animals↗

[Diagnostic and therapeutic consequences of kidney injuries in pediatric blunt abdominal trauma].

Renal lesions are frequently encountered in blunt pediatric abdominal trauma. In this retrospective study, we analyzed the incidence of renal trauma in these trauma patients to determine which diagnostic and therapeutic approaches were most predictive. From 1976 to 1996, 308 children sustaining blunt abdominal trauma were admitted to our department. Patients were evaluated using abdominal paracentesis, ultrasonography, and urinary analysis. In specific cases, i.v. urography, CT scan, and/or angiography were applied. We used the Organ Injury Scale (OIS) for classification of renal trauma into five grades. We encountered 69 serious abdominal traumas. Thirty-six patients sustained renal lesions grade 2 (G2) or higher; 20 children were polytraumatized. There were 67 renal lesions with 28 G1, 22 G2, 8 G3, 5 G4, 1 G5, and 3 lesions of the urinary tract. Ultrasonography and urinary analysis were found to be optimal diagnostic means for screening and observing the course of renal lesions. For lesions G2 or higher, CT scan was the most reliable in classifying and diagnosing renal lesions. This superseded i.v. urography. If no contrast medium was excreted in the CT scan, angiography was indicated. Only ten patients proceeded to operative therapy. During the period reviewed, a shift from operative to conservative treatment was notable with a tendency toward minimally invasive therapy. If lesions were G4 or G5, operative treatment was always indicated.

Abdominal Injuries↗

Transplant activities in Germany in 1998--a survey facilitated by the National Registry for Hemopoietic Stem Cell Transplantation.

To improve the infrastructure of hemopoietic stem-cell transplantations in our country, the German Registry for Hemopoietic Stem-Cell Transplantations (DRST) was established in 1998. The present paper summarizes the current status of the DRST and gives a survey of transplant activities in Germany in 1998 in terms of transplant units, transplant types, transplant frequencies and underlying diseases.

Blood Cells↗

Patients with malignant lymphomas experience a higher rate of documented infections than patients with breast cancer after high-dose chemotherapy with autologous peripheral stem cell transplantation.

The influence of underlying disease on documented infections has rarely been addressed in patients treated with high-dose chemotherapy (HDCT) and subsequent autologous peripheral blood stem cell transplantation (PBSCT). Because autografting has been used most frequently for malignant lymphomas and breast cancer, we analyzed in a retrospective study the data of 100 consecutive adult patients with either malignant lymphomas (group A, n = 50) or breast cancer (group B, n = 50) treated with HDCT at a single institution. The number of autografted CD34+ cells was not statistically different in either group. In this paper, we show for the first time that there is a significant difference in clinically or microbiologically documented infections in these groups of patients: documented infections occurred in 30% of malignant lymphoma patients but only in 4% of breast cancer patients (P=0.001). Of all isolated microorganisms, 78% were gram-positive. Because most of the documented infections were due to staphylococci, further studies should prospectively evaluate preventive measures to reduce the high incidence of these infections. This is especially important for lymphoma patients, who can be regarded as a high-risk group concerning gram-positive bacteremia.

Adult↗

Expression and cell-specific localization of the cholecystokinin B/gastrin receptor in the human stomach.

Gastrin stimulates gastric acid secretion by acting on the cholecystokinin B/gastrin receptor (CCK-BR). The localization of this receptor at the cellular level showed conflicting results in animal studies and has not been described in man by immunohistochemistry. The aim of the present study is to characterize the precise cellular location of the CCK-BR in the human stomach. Polyclonal antisera were raised against different epitopes of the CCK-BR molecule and used for immunohistochemical investigations. CCK-BR mRNA was detected in paraffin tissue sections by the highly sensitive method of in situ reverse transcriptase-polymerase chain reaction (RT-PCR). Using immunohistochemistry, CCK-BR could successfully be localized in gastric parietal cells. In the majority of parietal cells, CCK-BR immunoreactivity was present a he basolateral cell membrane domain. In some parietal cells, a granular pattern of immunoreactivity was exclusively confined to the cytoplasm of the cells. CCK-BR mRNA was found in parietal cells and in enterochromaffin-like (ECL) cells by means of in situ RT-PCR. No expression of CCK-BR was found in the gastric antral mucosa. Our data support the concept that gastrin stimulates gastric acid secretion directly via CCK-B receptors on parietal cells and indirectly by inducing histamine release from histamine-containing ECL cells, which contributes to acid secretion by parietal cells.

Amino Acid Sequence↗

Immediate toxicity during fractionated total body irradiation as conditioning for bone marrow transplantation.

BACKGROUND: Total body irradiation followed by bone marrow transplantation is well established as a part of the conditioning regimen in high dose therapy. The immediate tolerance of fractionated total body irradiation (FTBI) was investigated prospectively. METHODS: From January 1995 to December 1998 162 patients received a FTBI, 6x2 Gy on 3 consecutive days, lung dose 10 Gy, for allogeneic (n=112) or autologous (n=50) bone marrow transplantation. High dose chemotherapy (mostly Cyclophosphamide) was administered after the FTBI. A standardized supportive therapy was administered. The immediate toxicity of FTBI was evaluated prospectively prior to each radiation fraction using a defined questionnaire. RESULTS: Main symptoms distressing the patient during irradiation period were gastrointestinal symptoms like nausea and emesis. The prevalence of nausea per fraction increased to 26.1% after the 4th fraction, with a significant higher prevalence in children younger than 10 years at 1st and 2nd fractions. 42.6 and 22. 8%, respectively, of all patients complained of nausea and episodes of emesis, during FTBI. Mild xerostomia and parotiditis were observed in 29.9 and 7.1% of all patients. Further gastrointestinal side effects during FTBI were loss of appetite in 16.0%, indisposition in 25.3%, mild oesophagitis in 3.7% and diarrhoea in 3. 7% of the patients. During FTBI 41.4% of the patients developed a temporary skin irritation (mild erythema). Pruritus was registered in 3.7% of the patients. Headache was observed in 14.8% and Fatigue syndrome in 49.2% of women and 28.3% of men (P<0.005). CONCLUSION: FTBI is a well tolerated therapeutic regimen in high dose therapy. The 162 patients investigated revealed no severe immediate side effects.

Adolescent↗

Treatment of Adult ALL according to protocols of the German Multicenter Study Group for Adult ALL (GMALL).

The German Multicenter Study Group for Adult Acute Lymphoblastic leukemia (GMALL) has conducted 5 consecutive trials with more than 3000 patients since 1981. This article provides an overview on aims, treatment concepts, and results of these studies. It includes brief summaries on the development of prognostic models within the GMALL group and on approaches for prophylaxis of CNS relapse, and it summarizes specific treatment concepts for mature B-lineage acute lymphocytic leukemia.

Adolescent↗

Non-infectious lung complications are closely associated with chronic graft-versus-host disease: a single center study of incidence, risk factors and outcome.

Non-infectious lung complications (NILC) are frequent, influencing morbidity and mortality of patients after allogeneic BMT. Although the term NILC encompasses a number of different entities, an association with GVHD has been noted for almost all of them. Our study was directed towards assessing the incidence and risk factors for developing NILC, as well as the response to treatment and long-term outcome. Forty (14.7%) out of 272 patients surviving for more than 3 months after allogeneic BMT, developed lung complications fulfilling the criteria for NILC. The evaluation was based on clinical investigation, radiologic imaging, lung function tests, broncho-alveolar lavage and biopsies. Risk factors were assessed by univariate and multiple statistical regression models, where chronic GVHD proved to be the only significant risk factor for the development of NILC (P = 0.011). In three patients NILC developed in direct association with donor lymphocyte infusions. The majority of patients responded well to treatment with corticosteroids and immunosuppressive drugs. NILC had no adverse effect on survival. The frequency of NILC was low in autologous (5%) as compared with allogeneic transplants (14.7%) but this difference was not statistically significant. Bone Marrow Transplantation (2000) 25, 1263-1268.

Bone Marrow Transplantation↗

The efficacy of a 40-mg extended-release formulation of cisapride in the treatment of patients with gastro-oesophageal reflux.

BACKGROUND: This study was conducted to assess the efficacy of a novel 40-mg extended-release formulation of cisapride in reducing gastro-oesophageal reflux. METHODS: According to a double-blind, randomized, placebo-controlled design, 19 patients with pathological gastro-oesophageal reflux were treated with extended (40 mg o.d.) or immediate (10 mg q.d.s.) release formulations for two periods of 4 days each (pH-monitoring on day four). Patients received identical treatments in both periods to allow limits of agreement defining equivalent potency of both formulations to be derived from intra-individual variability of treatment effects. RESULTS: The extended-release formulation decreased total and upright reflux times by 5.5 +/- 1.3% and 8.1 +/- 2.1% (P < 0.001), respectively. It did not change the percentage supine reflux time but diminished the mean duration of reflux episodes by 1.0 +/- 0.4 min (P=0.005). The total number of reflux episodes remained unaltered with both formulations. Immediately-released cisapride decreased total, upright, and supine acid exposures by 5.8 +/- 1.3%, 6.8 +/- 1.6% (P < 0.002) and 3.6 +/- 1.8%, respectively, and mean duration of episodes by 0.9 +/- 0.2 min (P </= 0.05). Equivalent potency for both formulations was accepted in terms of percentage total and upright acid exposure and mean duration of episodes. CONCLUSIONS: The 40-mg extended-release formulation of cisapride decreases total acid exposure and in this study is equivalent to the conventional immediate-release 10 mg q.d.s. regimen. Cisapride primarily interferes with reflux by improving oesophageal acid clearance.

Adolescent↗

Dominant beta-thalassaemia: a highly unstable haemoglobin is caused by a novel 6 bp deletion of the beta-globin gene.

Beta-thalassaemia is inherited as an autosomal recessive trait in most families. Particular interest has recently been focused on the molecular pathology of the rare forms with a dominant mode of inheritance. The index patient and her mother, who are described in this report, displayed typical clinical and haematological features of beta-thalassaemia intermedia with significant ineffective erythropoiesis and additional peripheral haemolysis. Molecular analysis demonstrated a heterozygous genotype for a novel 6 bp (TGGTCT) deletion of the beta-globin gene involving codons 33-35. This deletion results in the removal of two valine residues from the beta-globin chain at position 33/34 (B15/B16) and the substitution of the tyrosine residue at position 35 (C1) by an aspartic acid (beta 33-35 [B15-C1] Val-Val-Tyr-->0-0-Asp). According to the index patient's place of birth, this abnormal haemoglobin has been termed Hb Dresden. The stability of the variant and the normal beta-globin chains were similar during the incubation period of in vitro globin chain synthesis analysis. However, Hb Dresden is exquisitely unstable and cannot be detected in the peripheral blood by haemoglobin electrophoresis, high-performance liquid chromatography (HPLC) or isoelectric focusing. This instability can be explained by the vital structural role of the three affected amino acids that, in normal haemoglobin, establish a total of nine intermolecular bonds (five hydrophobic and four polar) at both the alpha1beta1 (alpha2beta2) and the alpha1beta2 (alpha2beta1) interface.

DNA↗

Haematopoietic stem cell transplantation for patients with myelo-dysplastic syndromes and secondary acute myeloid leukaemias: a report on behalf of the Chronic Leukaemia Working Party of the European Group for Blood and Marrow Transplantation (EBMT).

Allogeneic stem cell transplantation from an HLA-identical sibling donor is a curative treatment option for a young patient with myelodysplastic syndrome, limited by age and lack of sibling donors. Alternative stem cell sources have been used more recently, such as unrelated donors, non-identical family members or autologous transplants. This analysis of 1378 transplants reported to the European Group for Blood and Marrow Transplantation (EBMT) addresses the outcome of the varying procedures according to the known risk factors. The estimated disease-free survival (DFS) and estimated relapse risk at 3 years were both 36% for 885 patients transplanted with stem cells from matched siblings. In the multivariate analysis, age and stage of disease had independent prognostic significance for DFS, survival and treatment-related mortality. Patients transplanted at an early stage of disease had a significantly lower risk of relapse than patients transplanted at more advanced stages. The estimated DFS at 3 years was 25% for the 198 patients with voluntary unrelated donors, 28% for the 91 patients with alternative family donors and 33% for the 126 patients autografted in first complete remission. The non-relapse mortality was 58% for patients with unrelated donors, 66% for patients with non-identical family donors and 25% for autografted patients. The relapse rate of 18% was relatively low for patients with non-identical family donors, 41% for patients with unrelated donors and 55% for patients treated with autologous stem cell transplantation. Both allogeneic and autologous stem cell transplantation have emerged as treatment options for patients with myelodysplastic syndromes. Transplantation with an HLA-identical sibling donor is the preferred treatment option. Patients without an HLA-identical sibling donor may be treated with either autologous stem cell transplantation or an alternative donor transplantation. Patients younger than 20 years may be treated with an unrelated donor transplantation. Patients older than 40 years, and probably also patients between 20 and 40 years, may benefit most from an autologous stem cell transplantation.

Actuarial Analysis↗

mRNA expression patterns of insulin-like growth factor system components in human neuroendocrine tumours.

BACKGROUND: Insulin-like growth factors (IGF) and their corresponding receptors and binding proteins are important in carcinogenesis for several tumours, but their expression pattern in the functionally and biologically heterogeneous human neuroendocrine tumours of the gastroenteropancreatic tract is largely unknown. MATERIALS AND METHODS: This study searched for the mRNA expression patterns of components of the IGF system: IGF-1 and IGF-2, IGF receptors 1 and 2 (IGF-1R, IGF-2R), IGF-binding proteins 1-6 (IGFBP1-6)) in the most frequent human gastroenteropancreatic neuroendocrine tumours (gastrinomas, insulinomas, tumours associated with carcinoid syndrome and functionally inactive tumours) employing reverse transcriptase-polymerase chain reaction (RT-PCR). RESULTS: In the 37 tumour samples analysed (nine gastrinomas, 10 insulinomas, nine tumours associated with carcinoid syndrome and nine functionally inactive tumours) IGFBP-2 was found in all tumour samples while the IGFBP-1 was expressed only at low frequency (10-22%) among the four tumour types. The IGF-2R was predominantly expressed in gastrinomas. Among the four tumour types the expression of IGF-1R, IGF-2R and IGFBP-6 varied significantly. In addition, 12 pairs of significantly coexpressed IGF system components were detected (IGF-1 <--> IGF-1R, IGF-1 <--> IGF-2R, IGF-1 <--> IGFBP-3, IGF-1 <--> IGFBP-6, IGFBP-3 <--> IGF-1R, IGFBP-6 <--> IGF-1R, IGFBP-1 <--> IGF-2R, IGFBP-3 <--> IGF-2R, IGFBP-5 <--> IGF-2R, IGFBP-3 <--> IGFBP-5, IGFBP-3 <--> IGFBP-6, IGFBP-5 <--> IGFBP-6). CONCLUSIONS: The described differences of the expression patterns of the IGF system components in neuroendocrine tumour subtypes suggest tumour type-dependent different pathways in tumour growth control by IGF system components.

Gastrinoma↗

Neuropeptide Y in the paraventricular nucleus of the hypothalamus stimulates colonic transit by peripheral cholinergic and central CRF pathways.

There is evidence suggesting that neuropeptide Y (NPY) as well as corticotropin-releasing factor (CRF) in the paraventricular nucleus of the hypothalamus (PVN) are involved in the CNS regulation of gastrointestinal (GI) function. We studied the effects of NPY or Y1-and Y2-receptor agonists microinjected into the PVN on colonic transit. Microinjection of NPY into the PVN at doses of 0.15-1.5 microg decreased the colonic transit time of conscious rats up to 49%. Pretreatment with the peripherally acting cholinergic antagonist atropine methyl nitrate (0.1 mg kg-1 i.p.) blocked the NPY into PVN-induced effect on colonic motor function.The agonist of the Y1-receptor, NPY(Leu31, Pro34), as well as the Y2-receptor agonist, NPY(13-36), dose-dependently decreased colonic transit time when microinjected into the PVN (0.05, 0.15 and 0.5 microg). However, the Y1-receptor agonist was more effective. Intracerebroventricular (ICV) application of the CRF-receptor antagonist, alpha-helical-CRF9-41 (50 microg/rat), blocked the NPY effect in the PVN on colonic motor function. In conclusion, stimulation of colonic transit by NPY acting in the PVN was observed. The PVN is more sensitive to agonists acting on the Y1- than on the Y2-receptor to mediate stimulation of propulsive colonic motility. The effect of NPY in the PVN on colonic motor function depends on central CRF and peripheral cholinergic pathways.

Animals↗

Management of kidney injuries in children with blunt abdominal trauma.

BACKGROUND/PURPOSE: The authors analyzed the incidence and the course of renal injuries encountered in a cohort of pediatric patients with blunt abdominal trauma. This review focuses on the early diagnostic and therapeutic approach rather than the long-term outcome and draws conclusions for an effective initial management. METHODS: From 1976 to 1996, the charts of 308 children with blunt abdominal trauma that were admitted to the authors' department were reviewed. The patients initially were evaluated using urinalysis, ultrasonography, and abdominal paracentesis (until 1984) and in specific cases iv-urography, computed tomography (CT), and angiography. The authors retrospectively classified the renal trauma after the widely used Organ Injury Scaling (OIS) into 5 grades and correlated the diagnostic value of various techniques as well as the diagnostic approach. RESULTS: Sixty-nine serious abdominal traumas were encountered. Thirty-six patients suffered renal lesions grade 2 (G2) or higher; 20 children were polytraumatized. There were 67 renal lesions including 28 G1, 22 G2, 8 G3, 5 G4, 1 G5, and 3 lesions of the lower urinary tract. Ultrasonography and urinalysis were found to be the optimal diagnostic methods for screening and following the course of renal injury. CT scan proved to be most reliable for detecting and exactly classifying renal lesions grade 2 or higher and superseded consecutively iv-urography. In cases in which CT scan failed to show renal excretion of contrast agent, angiography was performed. Ten patients proceeded to operative therapy. CONCLUSIONS: Ultrasonography and urinalysis proved to be the optimal initial evaluation tool for excluding renal injury both as a screening method and for further controls. Exact classification was possible by CT scan. During the reviewed time period a shift from surgical to conservative management was notable. If lesions were G4 or G5, surgical treatment with tendency toward minimally invasive therapy always was indicated.

Abdominal Injuries↗

Use of an unmanned police car to reduce traffic speed.

OBJECTIVE: Motor vehicle collisions are the most common mechanism of traumatic death. Speeding is often implicated as a causal factor in motor vehicle crashes. One potential intervention, to prevent speeding, is the placement of a roadside unmanned police car. This study sought to answer the following questions: is speeding reduced by this intervention, does this intervention lose effectiveness over time, and when the car is removed, do motorists resume speeding? METHODS: A radarless speed detector was placed on a roadway that had a history of speed-related collisions. Baseline speeds were recorded for 12 days. Thereafter, an unmanned police cruiser was parked near the road, and speeds were recorded for 10 days. The police car was removed, and data collection continued 1 more week. The difference between the proportion of motorists exceeding 45-mph in the baseline period and the decoy intervention period was tested by using a chi2 test. RESULTS: During the baseline surveillance, 72.0% of vehicles (186,578 of 259,074 motorists) had speeds greater than 45 mph. After placement of the unmanned police car, 41.0% of motorists (92,272 of 225,026 motorists) exceeded 45 mph (p < .0001). Over the 10-day study period, when the decoy police car was in place, the percentage of motorists exceeding 45 mph gradually increased from 27.2% to 47.4%. Upon removal of the police car, speeding returned approximately to baseline, with 67.5% of motorists (120,640 of 178,752 motorists) exceeding 45-mph. CONCLUSION: Parking an unmanned police car beside a road was associated with a large reduction in speeding over a 10-day period. Removal of the unmanned police car resulted in a return to preintervention speeding.

Accidents, Traffic↗

The combination of medical treatment plus multicomponent behavioral therapy is superior to medical treatment alone in the therapy of irritable bowel syndrome.

OBJECTIVE: Although the standard treatments for the irritable bowel syndrome (IBS) are medical, growing evidence indicates the substantial therapeutic value of psychological therapy. However, it has not been investigated whether the combination of multicomponent behavioral therapy plus medical treatment is more effective than medical treatment alone. The aim of this study was to investigate this question in patients consulting a tertiary gastrointestinal (GI) referral center. METHODS: Twenty-four IBS outpatients were randomly assigned to the combination of standardized multicomponent behavioral therapy plus standard medical treatment (SMBT) or standard medical treatment alone (SMT). SMBT included IBS information and education, progressive muscle relaxation, training in illness-related cognitive coping strategies, problem-solving, and assertiveness training in 10 sessions over 10 wk. SMT included standardized symptom-oriented medical treatment and regular visits to a gastroenterologist every second week. Posttreatment outcome measures consisted of quantification of GI, vegetative, and psychological symptoms by means of daily symptom diaries and the assessment of changes in rectovisceral perception thresholds, as well as of questionnaire measures on psychological distress, overall well-being, illness-related coping abilities, and quality of life. Follow-ups were conducted at 3- and 6-month intervals. RESULTS: Pre- and posttreatment evaluations showed significantly (p < 0.01) greater IBS symptom reduction as measured by daily symptom diaries for the SMBT group than for the SMT group. Rectovisceral perception remained unchanged by either treatment. Overall well-being significantly improved in the SMBT group but remained unchanged in the SMT group. Subjects in the SMBT group, unlike those in the SMT group, felt significantly more in control of their health, and quality of life was significantly improved in the SMBT group but remained unchanged in the SMT group. CONCLUSIONS: The data provide evidence that the combination of medical treatment plus multicomponent behavioral treatment is superior to medical treatment alone in the therapy of IBS.

Adaptation, Psychological↗