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Medizin - Open Access LMU - Teil 13/22 Archiv

250 Episoden
1 minute
To investigate mechanisms of cell-mediated injury in renal inflammatory disease it is critical to determine the surface phenotype of infiltrating renal leukocyte subsets. However, the cell-specific expression of many leukocyte receptors is difficult to characterize in vivo. Here, we report a protocol based on flow cytometry that allows simultaneous characterization of surface receptor expression on different subsets of infiltrating renal leukocytes. The described technique combines an adapted method to prepare single cell suspensions from whole kidneys with subsequent four-color flow cytometry. We recently applied this technique to determine the differential expression of murine chemokine receptors CCR2 and CCR5 on infiltrating renal leukocyte subsets. In this article, we summarize our current findings on the validity of the method as compared with immunohistology and in situ hybridization in two murine models of nonimmune ( obstructive nephropathy) and immune-mediated ( lupus nephritis) inflammatory renal disease. Flow cytometry analysis revealed an accumulation of CCR5-, but not CCR2-positive lymphocytes in inflamed kidneys, compared to the peripheral blood. Particularly renal CD8(+) cells expressed CCR5 (79% in obstructed kidneys, 90% in lupus nephritis). In both models, infiltrating renal macrophages were positive for CCR2 and CCR5. These data corresponded to immunohistological and in situ hybridization results. They demonstrate that flow cytometric analysis of single cell suspensions prepared from inflamed kidneys is a rapid and reliable technique to characterize and quantify surface receptor expression on infiltrating renal leukocyte subsets.
1 minute
The major neurotransmitter of the central nervous system, gamma-aminobutyric acid (GABA), exerts its actions through GABA(A), GABA(B) and GABA(C) receptors. GABA and GABA receptors are, however, also present in several non-neural tissues, including the endocrine organs pituitary, pancreas and testis. In the case of the rat testis, GABA appears to be linked to the regulation of steroid synthesis by Leydig cells via GABA(A) receptors, but neither testicular sources of GABA, nor the precise nature of testicular GABA receptors are fully known. We examined these points in rat, mouse, hamster and human testicular samples. RT-PCR followed by sequencing showed that the GABA-synthesizing enzymes glutamate decarboxylase (GAD) 65 and/or GAD67, as well as the vesicular GABA transporter vesicular inhibitory amino acid transporter (VIAAT/VGAT) are expressed. Testicular GAD in the rat was shown to be functionally active by using a GAD assay, and Western blot analysis confirmed the presence of GAD65 and GAD67. Interstitial cells, most of which are Leydig cells according to their location and morphological characteristics, showed positive immunoreaction for GAD and VIAAT/VGAT proteins. In addition, several GABA(A) receptor subunits (alpha1-3, beta1-3, gamma1-3), as well as GABAB receptor subunits R1 and R2, were detected by RT-PCR. Western blot analysis confirmed the results for GABA(A) receptor subunits beta2/3 in the rat, and immunohistochemistry identified interstitial Leydig cells to possess immunoreactive GABA(A) receptor subunits beta2/3 and alpha1. The presence of GABA(A) receptor subunit alpha1 mRNA in interstitial cells of the rat testis was further shown after laser microdissection followed by RT-PCR analysis. In summary, these results describe molecular details of the components of an intratesticular GABAergic system expressed in the endocrine compartment of rodent and human testes. While the physiological significance of this peripheral neuroendocrine system conserved throughout species remains to be elucidated, its mere presence in humans suggests the possibility that clinically used drugs might be able to interfere with testicular function. Copyright (C) 2003 S. Karger AG, Basel.
1 minute
Unlike other antidepressants, mirtazapine does not inhibit the reuptake of norepinephrine or serotonin but acts as an antagonist at presynaptic alpha(2)-receptors, at postsynaptic 5-HT2 and 5-HT3 receptors, and at histaminergic H1 receptors. Furthermore, mirtazapine has been shown to acutely inhibit cortisol secretion in healthy subjects. In the present study, the impact of mirtazapine treatment on salivary cortisol secretion was investigated in 12 patients (4 men, 8 women) suffering from major depression according to DSM-IV criteria. Patients were treated with mirtazapine for 3 weeks, receiving 15 mg mirtazapine on day 0, 30 mg on day 1 and 45 mg per day from day 2 up to the end of the study (day 21). Response to mirtazapine treatment was defined by a reduction of at least 50% in the Hamilton Rating Scale for Depression after 3 weeks of therapy. Salivary cortisol concentrations were measured before treatment (day -1), at the beginning of treatment (day 0), after 1 week (day 7) and after 3 weeks (day 21) of treatment with mirtazapine. Saliva samples were collected hourly from 08.00 until 20.00 h. The area under the curve values served as parameter for the salivary cortisol secretion. Following analysis of variance with a repeated measures design, tests with contrasts revealed a significant reduction of cortisol concentrations already after 1 day of mirtazapine treatment that was comparable in responders and nonresponders. In addition to new pharmacological approaches such as CRH1 receptor antagonists, mirtazapine therefore appears to be an effective strategy to decrease hypercortisolism and restore HPA system dysregulation in depression. However, the importance of the acute inhibitory effects of mirtazapine on cortisol secretion for its antidepressant efficacy has to be further clarified. Copyright (C) 2003 S. Karger AG, Basel.
1 minute
This was a double-blind placebo-controlled study with a cross-over design to examine the effects of scopolamine on cognitive functions in young healthy subjects. Scopolamine hydrobromide was administered subcutaneously to 12 subjects (mean +/- SD age 23.8 +/- 2.2 years) at doses of 0.3 and 0.6 mg in comparison with two placebo conditions. Scopolamine at both doses produced marked sedation as rated by subjects and an observer. In the continuous performance test, vigilance was impaired by both doses of scopolamine. The span of apprehension test showed differing results (only the high dose of scopolamine showed a performance decrement only in the three-character version of the span of apprehension test). Significant impairment by both doses of scopolamine was seen in immediate and delayed free recall, continuous visual recognition, running word recognition and running picture recognition. While scopolamine caused a significant slowing in average reaction times for simultaneous matching as well as for delayed matching, subjects made more errors under scopolamine compared to placebo only in delayed matching, not in simultaneous matching. Also, the main outcome of matching to sample showed significant effects only in delayed matching, not in simultaneous matching. Notable in this study is the incongruity between the simultaneous matching test and the span of apprehension test on the one hand and the other cognitive tests used on the other. These results demonstrated that scopolamine has a greater effect on memory than on attention. Thus, the scopolamine-induced effects in the present study seem to be more relevant to Alzheimer's disease in an advanced phase than to normal aging. Copyright (C) 2003 S. Karger AG, Basel.
1 minute
Gemcitabine is an antimetabolite drug with proven antitumor activity and tolerability in metastatic breast cancer. In a total of nine studies, gemcitabine monotherapy has reached response rates of up to 37% in the first-line setting, 26% in the second-line setting, and 18% or better in the third-line setting. Gemcitabine is an excellent choice for combination therapy by its unique mechanism of action and favorable toxicity profile, thus limiting the risk of pretreatment-related drug resistance and overlapping toxicity, and by its potential for synergistic interaction with some combination partners as indicated in preclinical studies. Numerous phase II clinical studies have combined gemcitabine with other active agents such as the taxanes, vinorelbine, vindesine, cisplatin, 5-fluoro-uracil, as well as anthracyclines across various regimens and conditions of pretreatment. Most of these two-drug combinations have consistently demonstrated higher efficacy than either single agent, particularly in pretreated patients. Even higher efficacy has been obtained with triple-drug regimens including gemcitabine, anthracyclines (epirubicin or doxorubicin), and paclitaxel; these regimens have yielded overall response rates of 58-92% as first-line treatment. In view of these results, gemcitabine may be regarded as a valuable alternative to the palliative treatment of metastatic breast cancer, and an excellent option for the development of effective combination treatment not only in first-line therapy, but also for intensively pretreated patients previously exposed to anthracyclines and/or the taxanes. Copyright (C) 2003 S. Karger AG, Basel.
1 minute
Objective: Angina pectoris, arrhythmic sudden death and myocardial infarction, all these cardiac events have occasionally been reported during 5-fluorouracil (5-FU) chemotherapy. Underlying mechanisms leading to these events are unknown; damage to the myocytes or vasospasms have been discussed. Methods: 102 consecutive and unselected patients were monitored with 12-lead ECG, echocardiography and radionuclide ventriculography prior to the first cycle of 5-FU chemotherapy and 3 months from baseline. Results: 19% of the patients developed reversible symptoms of angina pectoris during treatment which lasted up to 12 h after cessation of the infusion. Most of the 19 patients showed corresponding ECG changes. 6 out of the 19 patients with severe angina pectoris had subsequent coronary angiography. In none of these patients the coronary angiography showed coronary artery disease, but it showed low ventricular function (ejection fraction
1 minute
High-dose chemotherapy with autologous peripheral blood stem cell transplantation is the standard treatment of patients with multiple myeloma today. In this study we used a combination mobilizing chemotherapy containing ifosfamide with G-CSF before stem cell collection. The chemotherapy regimen consisted of ifosfamide (2,500 mg/m(2) days 1-3), epirubicin (100 mg/m(2) day 1) and etoposide (150 mg/m2 days 1-3) followed by G-CSF (5 mug/kg from day 5). In 30 younger patients (median age 51 years; range 41-60 years) who received the IEV regimen in 100% dosage, a median of 11.15 x 10(6) CD34(+) cells/kg (range 0-44.60 x 10(6) CD34(+) cells/kg) was collected. In 22 elder patients (median age 64 years; range 59-72 years) similar collection results were obtained with a median of 10.82 x 10(6) CD34(+) cells/kg (range 0.99-42.22 x 10(6) CD34(+) cells/kg) after the IEV regimen in 75% dosage. The pretreatment chemotherapy cycles before mobilization were fewer in elder patients with a median of 0 cycles (range 0-7 cycles) compared with younger patients with a median of 4 cycles (range 0-7 cycles). These collection results were favorable and allowed to support a tandem transplantation procedure in younger and elder patients in 97 and 95%, respectively. In the majority of patients, the hematological toxicity of IEV was of WHO grade 3/4. The extramedullary toxicity was mild to moderate and there were only few cases (5-10%) of relevant nephrotoxicity or neurotoxicity associated with the application of ifosfamide. Copyright (C) 2003 S. Karger AG, Basel.
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For high-risk soft tissue sarcomas (HR-STS) of adults, new treatment strategies are needed to improve outcome with regard to local control and overall survival. Therefore, systemic chemotherapy has been integrated either after (adjuvant) or before (neoadjuvant) optimal local treatment by surgery and radiotherapy in HR-STS. The combination with regional hyperthermia as a new treatment strategy seems to open a new therapeutic window. Copyright (C) 2003 S. Karger AG, Basel.
1 minute
Randomized trials performed in anthracycline-pretreated breast cancer patients have demonstrated good activity of taxane-based regimens. In a face to face comparison, single-agent docetaxel proved to be significantly more effective than paclitaxel. Treatment with docetaxel was also associated with an increased incidence of grade grade-3/4 toxicities in this trial. Antitumor activity of taxane-based combination regimens was clearly superior to single-agent therapy in two trials. As anticipated, treatment-associated toxicity was greater with combination regimens, but this did not affect quality of life.
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Background: The prognosis for patients with malignant astrocytoma or brain metastases is often fatal despite intensive therapy. Therefore we wished to elucidate whether the quality of life (QoL) is a determinant of overall survival (OAS). Patients and Methods: From 1997 to 2000 153 patients with brain tumours were screened; 39 patients (26%) refused to participate and further 47 patients were excluded (cerebral impairment 14%, amaurosis/language problems 3%, Karnofsky performance score < 50% 7%, death 8%, non-compliance 7%). Thus, 57 patients were analysed (33 with primary brain tumours, 24 with brain metastases). With the FACT-G questionnaire cancer-specific aspects of health-related QoL were assessed. Results: Patients with metastases showed a lower QoL in the physical sphere than patients with astrocytoma, but there were no significant differences in OAS. Median survival of patients with good QoL was 31.3 months versus 14.2 months in patients with bad QoL. Only the two variables `living with a spouse' and FACT-G sum score had a statistically significant influence on survival (p = 0.033 and p = 0.003) modelled by the Cox-PH regression. Patients who did not live with a spouse had shorter survival times than the other patients. Conclusion: Health-related QoL can serve to identify a patient group with higher risks of death.
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Background: Aim of the study was to assess the value of scintimammography using Tc-99m sestamibi in the evaluation of tumor response to neoadjuvant chemotherapy. Material and Methods: Results were calculated for 9 patients undergoing neoadjuvant chemotherapy. Scintimammography using 740 MBq Tc-99m sestamibi was performed before, during and after chemotherapy, and sestamibi uptake was scored visually and semiquantitatively to evaluate tumor response. Results: In the case of complete response (n = 3) sestamibi uptake decreased 8 days after beginning neoadjuvant chemotherapy and normalized in the following course. Focal uptake decreased more slowly in patients with partial response (n = 3), who showed clear, persisting tracer accumulation after therapy. The patients without response (n = 3) showed a persisting high tumor activity even after chemotherapy was completed. Conclusions: The preliminary data suggest that in contrast to other imaging modalities scintimammography appears to yield early information regarding tumor response to neoadjuvant chemotherapy.
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Background: The local recurrence rate of colorectal cancer has been significantly reduced due to the use of combined radiochemotherapy. Despite this improvement regarding locally advanced tumour recurrences, the treatment strategy for pre-treated patients remains difficult and unresolved. Patients and Methods: We analysed treatment and follow-up data of 14 patients with local recurrence of rectal cancer who were treated with radiation therapy (RT), chemotherapy (CT) and regional hyperthermia (RHT) from November 1997 to December 2001. Nine of these patients had received irradiation and CT (=pre-treated patients) in the past. For this group, 30.6-39.6 Gy RT, 5-fluorouracil (5-FU) as a continuous infusion over 5 days per week (350 mg/m(2)/24 h) combined with RHT twice a week was given. The 5 remaining patients (=not pre-treated) received conformal irradiation of 45 Gy with a boost between 9 and 14.4 Gy, combined with continuous infusion of 5-FU on days 1-4, and 29-33 (500 mg/m(2)/24 h), and RHT twice a week. Response to therapy was evaluated by means of computed tomography (CT) or magnetic resonance imaging (MRI) and by clinical follow-up. Results: Among 13 evaluated cases, the overall objective response rate was 54% (5 complete responses, 2 partial responses). At mean follow-up of 13.9 months (range 5-32 months) 7 patients were alive. Conclusion: The therapeutic regimen appears to be active in the treatment of local recurrences of rectal cancer. Larger-scaled studies are needed to evaluate the potency of hyperthermia in this therapeutic strategy.
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Background: Serial kinetics of serum CA 19-9 levels have been reported to reflect response and survival in patients with pancreatic cancer undergoing surgery, radiotherapy, and chemotherapy. We prospectively studied serial kinetics of serum CA 19-9 levels of patients with locally advanced or metastatic disease treated with gemcitabine and cisplatin. Patients and Methods: Enrolled in the study were 87 patients (female/male = 26/61; stage III/IV disease = 24/63). Patients received gemcitabine 1,000 mg/m(2) on days 1, 8, and 15 plus cisplatin 50 mg/m(2) on days 1 and 15, every 4 weeks. Serum samples were collected at the onset of chemotherapy and before the start of a new treatment cycle (day 28). Results: 77 of 87 patients (88.5%) with initially elevated CA 19-9 levels were included for evaluation. According to imaging criteria, 4 (5.2%) achieved a complete remission and 11 (14.3%) achieved partial remission, yielding an overall response rate of 19.5%. 43 (55.8%) patients were CA 19-9 responders, defined by greater than or equal to50% decrease in CA 19-9 serum levels within 2 months after treatment initiation. Except for one, all patients who had responded by imaging criteria (n = 14) fulfilled the criterion of a CA 19-9 responder. Despite being characterized as non-responders by CT-imaging criteria (stable/progressive disease), 29 patients were classified as CA 19-9 responders (positive predictive value 32.5%). Independent of the response evaluation by CT, CA 19-9 responders survived significantly longer than CA 19-9 non-responders (295 d; 95% CI: 285-445 vs. 174 d; 95% CI: 134-198; p = 0.022). Conclusion: CA 19-9 kinetics in serum serve as an early and reliable indicator of response and help to predict survival in patients with advanced pancreatic cancer receiving effective treatment with gemcitabine and cisplatin.
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A unique sutural cataract was observed in a 4-generation German family to be transmitted as an isolated autosomal, dominant trait. Since mutations in the gamma-crystallin encoding CRYG genes have previously been demonstrated to be the most frequent reason for isolated congenital cataracts, all 4 active CRYG genes have been sequenced. A single base-pair change in the CRYGA gene has been shown, leading to a premature stop codon. This was not observed in 170 control individuals. However, it did not segregate with the disease phenotype. This is the first truncating mutation in an active CRYG gene without a dominant phenotype. As the CRYGA mutation did not explain the cataract, several other candidate loci (CCV, GJA8, CRYBB2, BFSP2, MIP, GJA8, central pouch-like, CRYBA1) were investigated by micro-satellite markers and linkage analysis, but they were excluded based on the combination of haplotype analysis and two-point linkage analysis. The phenotype in this family is due to a mutation in another sutural cataract gene yet to be identified.
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In order to examine the descriptive validity of ICD-10 schizophrenia, 1,476 consecutively admitted in-patients were included in the present study. ICD-10 schizophrenia (n = 951) was compared with other non-affective psychotic disorders {[}persistent delusional disorders (n = 51), acute and transient psychotic disorders (n = 116) and schizoaffective disorders (n = 354)] with respect to socio-demographic, symptomatological and other clinical parameters. Analyses revealed that it is possible to distinguish schizophrenia from other non-affective psychotic disorders according to ICD-10 criteria: schizophrenic patients were characterised by more pronounced negative symptoms and a lower global functioning. They were younger than patients with persistent delusional disorders and schizoaffective disorders but older than patients with acute and transient psychotic disorders. The results are in line with a high descriptive validity of ICD-10 schizophrenia and highlight the importance of negative symptoms for this diagnosis. Copyright (C) 2003 S. Karger AG, Basel.