Antioxidative treatment reverses imbalances of nitric oxide synthase isoform expression and attenuates tissue-cGMP activation in diabetic rats.

Oxidative stress and impaired bioactivity of vascular nitric oxide (NO) play an important role in the pathogenesis of macro- as well as microangiopathic complications in diabetes mellitus. To determine the cause of this impaired bioactivity, we tested the effect of long-term hyperglycemia and antioxidative treatment on tissue-specific endothelial (e)NOS- and inducible (i)NOS-expression and the main target of NO action, cGMP, in diabetic rats. After 4 weeks of hyperglycemia, eNOS-mRNA expression was significantly down-regulated in all tissues tested. In contrast, iNOS-mRNA was significantly up-regulated and tissue generation of cGMP significantly increased. Treatment with alpha-lipoicacid reversed changes of NOS-isoform expression as well as cGMP-concentration without changing blood glucose levels. In addition, oxidative stress significantly decreased in diabetic rats treated with alpha-lipoicacid. Together, diabetes regulates NOS-isoforms differentially by down-regulating eNOS and up-regulating iNOS. In addition, our data suggest that the cause of impaired endothelial vasodilatation in experimental diabetes is not degradation or inactivation of NO. On the contrary, these results support the concept of decreased reactivity of the vascular smooth muscle to NO or increased NO activity as a possible vascular damaging agent, e.g., by inducing apoptosis in vascular cells. Furthermore, our data show that antioxidative treatment is capable of reversing changes in the NO-cGMP system and may therefore be an important therapeutic option for preventing vascular damage in diabetes mellitus.

Mangan-enhanced MR imaging for the detection and localisation of small pancreatic insulinoma.

Insulinoma is the most common pancreatic endocrine tumor. Localization of small tumors remains a diagnostic challenge. Recently, Mangafodipir-enhanced MR imaging using a whole-body coil has been shown to be effective in the detection and staging of pancreatic cancer [3]. Localization of even small tumors is improved and surgical techniques, such as robotic-assisted surgery, have been made possible.

Macrophage migration inhibitory factor and development of type-1 diabetes in non-obese diabetic mice.

AIMS/HYPOTHESIS: T-cell activation by specific antigen has been found to increase macrophage migration inhibitory factor (MIF) expression, indicating its role as an important feature of T-cell activation in vitro and in vivo. To date, the potential role of MIF in the development of autoimmune-mediated diabetes mellitus has not been studied. METHODS: MIF-mRNA expression in splenic lymphocytes of spontaneously diabetic non-obese diabetic (NOD) mice (n=6), cyclophosphamide-treated NOD mice (n=6), 14-day-old non-diabetic NOD mice (n=7) and C57/Bl6 control mice (n=6) was monitored using an internally standardised competitive reverse transcription-polymerase chain reaction, and the MIF-protein levels were determined using Western blot analysis. In addition, the impact of intraperitoneally administered recombinant MIF-protein treatment on diabetes incidence in NOD mice was evaluated. RESULTS: MIF-mRNA expression was markedly increased in splenic lymphocytes of spontaneously diabetic NOD mice as well as in 8-week-old NOD mice treated with cyclophosphamide compared with 2-week-old non-diabetic NOD and healthy C57BL/6 control mice. Western blot analyses showed decreased lymphocytic MIF-protein content in diabetic as well as in cyclophosphamide-treated animals compared with 2-week-old non-diabetic NOD and healthy C57BL/6 mice, probably as a consequence of increased protein secretion. Furthermore, treatment of NOD mice with recombinant MIF-protein at 25 microg twice a week, from age 6 to 11 weeks, led to an increased diabetes incidence (86%; n=7) compared with untreated control groups (55%; n=20) at week 34. CONCLUSIONS/INTERPRETATION: In this study, we report for the first time that MIF-mRNA expression in splenic lymphocytes is up-regulated during development of cell-mediated diabetes in non-NOD mice. The data of our preliminary study suggest a possible role of MIF in autoimmune-inflammatory events, such as type-1 diabetes and also that anti-MIF therapeutic strategy might serve to attenuate autoimmune processes.

[The selective cyclooxygenase-2 inhibitor celecoxib is a safe alternative in patients with pseudo-allergic reactions to nonsteroidal anti-inflammatory drugs]. / Der selektive Cyclooxygenase-2-Inhibitor Celecoxib ist ein sicheres Ausweichpräparat bei Intoleranz gegenüber nichtsteroidalen Antiphlogistika.

BACKGROUND: Adverse reactions to nonsteroidal anti-inflammatory drugs (NSAIDs) are frequent, and the need to identify a safe alternative drug is a common problem in clinical practice. We assessed the tolerability of the selective cyclooxygenase-2 inhibitor celecoxib in a group of NSAID-sensitive patients. PATIENTS AND METHODS: 77 patients (24 males, 53 females, age 31-80 years) with a history of adverse reactions to NSAIDs underwent standardized skin prick, scratch and patch tests along with oral, placebo-controlled blinded exposure to celecoxib (maximum single dose 200 mg, cumulative daily dose 350 mg). RESULTS: 21 patients had a history of cutaneous reactions only (urticaria), 25 had encountered respiratory symptoms (asthma), 18 reported cutaneous as well as respiratory symptoms, and in 13 patients an anaphylactoid shock occurred. Acetylsalicylic acid triggered symptoms in 38 patients. In 46 cases, several NSAIDs of different chemical groups caused symptoms. Oral challenge with celecoxib was tolerated by all 77 patients without adverse effects. CONCLUSION: This study demonstrates that celecoxib does not have cross-intolerance to NSAIDs. Celecoxib is a safe alternative in subjects with previous adverse reactions to NSAIDs.

[Two consecutive pregnancies in a type 1 diabetic under treatment with insulin Lispro]. / Zwei konsekutive komplikationslose Schwangerschaften einer Typ-1-Diabetikerin unter Insulin Lispro.

BACKGROUND: Glucose control is mandatory in pregnant women with type 1 diabetes to keep the incidence of malformations and complications low. Insulin Lispro is a new and popular fast-acting insulin analog used for intensified insulin therapy. Although popular among young patients, this drug has not been licensed for use in pregnancy due to a possibly increased risk of fetal malformations. CASE REPORT: Retrospectively, the case of a 34-year-old woman with diabetes type 1, gravid III and para III, which carried her second and third child full time under Lispro treatment, was analyzed. We performed an interview of the patient and her doctors. Additionally, the pregnancy documents along with the examination documents of the children, our patient files, and the blood glucose documentation were investigated. Contrary to the first pregnancy which was carried out in the absence of Lispro (first degree hip dysplasia), both subsequent pregnancies were completely normal despite continuous Lispro therapy. HbA(1c) values in the range of 4.9-5.9% showed an adequate glucose control throughout these pregnancies. CONCLUSION: This case supports the hypothesis that insulin Lispro which is highly popular among young patients can safely and effectively be used in pregnancies. In order to be able to adequately assess possible risks associated with this application, additional cases need to be documented and analyzed.

Validation of a new automated immunoassay for measurement of intact osteocalcin.

Bone turnover is assessed indirectly by measurement of biochemical markers of bone turnover. Osteocalcin, a 49-amino-acid protein is a major noncollagenous protein of bone matrix, synthesized by osteoblasts and odontoblasts. Various assays exist for assessment of osteocalcin and concentrations in the same serum or plasma sample may vary enormously. The used antibodies may recognize intact osteocalcin and/or circulating fragments of osteocalcin. We here describe and validate a new automated immunoassay system for measurement of intact osteocalcin (DPC IMMULITE assay) using monoclonal antibodies (mouse) against the C-terminus of osteocalcin (AA 44-49). For detection polyclonal antibodies (goat) directed against the N-terminus (AA 1-17) conjugated with alkaline phosphatase are used. While different laboratory assays show marked clinical discordance, we evaluated our results comparatively to an established IRMA method (Nichols). We observed a highly significant correlation between both assays (r = 0.9352, p < 0.0001, n = 286) for healthy persons and also for patient samples (osteoporosis, diabetes type 1, rheumatoid arthritis). Very low inter- and intraassay covariance as well as highly significant linearity (analytical recovery near 100%) tested by serial dilutions were demonstrated for the DPC IMMULITE intact osteocalcin assay. We conclude that the IMMULITE assay is a useful method for assessment of intact osteocalcin giving valuable results in comparison to an established non-automated assay.

Polymerase chain reaction in the detection of tumor cells: new approaches in diagnosis and follow-up of patients with thyroid cancer.

Thyroid cancers are the most common endocrine malignancies and are being diagnosed with increasing frequency. In addition to other measures, diagnosis is based on fine-needle aspiration cytology examination. Recently, new assays using reverse transcription-polymerase chain reaction (PCR) are being tested to improve sensitivity and specificity of primary diagnosis and detection of recurrent thyroid cancer. In the preoperative diagnosis of thyroid cancer, several tissue- and/or tumor-specific mRNA have been described and in several cases, a higher sensitivity and specificity could be achieved using molecular techniques compared to conventional methods. In the postoperative follow-up of patients with thyroid cancer, conflicting data have been published and the use of PCR techniques revealed several problems of the molecular approach, which are based on some technical as well as biologic limitations. Despite these problems, which are discussed in detail in this review, molecular techniques may nevertheless improve the sensitivity and accuracy of fine-needle aspiration of thyroid nodules, fine-needle aspiration of metastases, and detection of recurrent disease in peripheral blood samples.