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Biomedical subjects

M Schmidt

Publications and source records attributed to M Schmidt.

At least 37 records · Page 2Linked to original sources

The combination of increased ovarian volume and follicle number is associated with more severe hyperandrogenism in German women with polycystic ovary syndrome.

The prevalence and relevance of polycystic ovaries (PCO) in German women with polycystic ovary syndrome has not been evaluated. This retrospective study included 212 PCOS patients (mean age 28 years) diagnosed by the NIH-criteria and consecutively recruited since 2003. Clinical features including anthropometric variables and the degree of hirsutism, family history, menstrual cyclicity as well as endocrine biochemical parameters were recorded. In addition, 3-h oral glucose tolerance testing for indices of insulin resistance and glucose metabolism was performed in each patient. Transvaginal ultrasound was used to detect polcystic ovaries, defined as the presence of at least one ovary > 10 ml or with at least 12 follicles of 2-9 mm diameter. In this German PCOS cohort, PCO were identified in 166 women (78%). Women with PCO (PXO+) had significantly higher LH/FSH ratios (median 2.1 vs. 1.7) and IGF-1 levels (median 182.5 vs. 160.5 ng/ml) compared to patients without PCO (PCO-). In addition, a significantly higher prevalence of acne (50% vs. 33%) and higher hirsutism scores (median 9 vs. 7) were found in PCO+ patients. Testosterone levels and the free androgen index (FAI) correlated significantly with ovarian volume and the number of ovarian follicles. Also, a subgroup of PCO+ women with a combination of increased ovarian volume and follicle number had higher testosterone levels (median 3.1 vs. 2.1 nmol/l) and FAI (median 7.6 vs. 4.5) compared to women with increased follicle count but normal volume. No differences were found in metabolic parameters or insulin resistance indices. PCO are common finding in German PCOS women. PCO appear to be associated with a more pronounced hyperandrogenemia, especially when both ovarian volume and follicle number are increased.

Adult↗

Radioiodine therapy of Graves' hyperthyroidism in patients without pre-existing ophthalmopathy: can glucocorticoids prevent the development of new ophthalmopathy?

BACKGROUND: Radioiodine therapy (RIT) combined with glucocorticoids is an effective therapy for Graves' disease, but it is debatable whether glucocorticoids should be applied in patients without Graves' ophthalmopathy (GO). METHODS: The effect of 0.4 - 0.5 mg prednisone every second day over a period of 5 weeks after RIT was monitored over a follow-up period of at least 12 months after RIT. A questionnaire was sent to 186 consecutive patients without GO concerning eye symptoms after RIT. 148 patients (80 %) answered. If eye symptoms had occurred after RIT, additional clinical examination was carried out at our outpatient clinic. The primary endpoint was the absence or onset of GO within the first year after RIT. RESULTS: Within 12 months after RIT the examination confirmed GO in 5 out of 148 patients (3.4 %). In all cases the symptoms were transient. No adverse reaction to the use of prednisone after RIT was noted. CONCLUSIONS: The risk of new GO in the first year after RIT was low and the clinical course of GO was mild when RIT was combined with a low-dose glucocorticoid regimen. Preventive administration of glucocorticoids can therefore be recommended in patients with Graves' disease even without evident GO.

Adult↗

Different T-cell receptor (TCR) zeta chain expression in cervical cancer and its precursor lesions.

OBJECTIVE: Cervical cancer is associated with infection of epithelial cells with the human papillomavirus (HPV) type 16 and HPV18. A functional signalling machinery in T-cells is required in order to successfully fight and eradicate HPV16+ transformed epithelial cells. One of the key signalling molecules associated with the T-cell receptor (TCR) is the homodimeric zeta chain molecule. MATERIAL AND METHODS: 28 formalin fixed und paraffin embedded samples of cervical tissue with cervical intraepithelial lesions CIN I (n = 3), CIN III (n = 7), invasive cervical carcinoma (CC) (n = 13) and normal cervical tissue (n = 5) has been evaluated for HPV-PCR und zeta chain immunohistochemistry. For immunohistochemistry a monoclonal IgG1 anti TZR zeta chain-antibody (mAb) has been used (clone 6B 10.2, Santa Cruz, Heidelberg, Germany). According to the performed Western-Blot analysis on peripheral blood monocytes (PBMCs) the used mAb has specifically recognized TCR zeta chains. RESULTS: We show reduced protein zeta chain expression associated with invasive cervical cancer, but not with pre-invasive HPV16-positive lesions or HPV16-negative normal cervix tissue. CONCLUSIONS: Thus, reduced TCR zeta chain expression is not necessarily linked to a chronic viral infection, nor to the presence of transformed cells, but rather to the stromal invasion of the cancer lesion.

Female↗

[Plastic reconstructive procedures of vulvar carcinoma: results and complications].

PURPOSE: This study describes the results of the plastic reconstructive measures in 207 patients with a primary or a recurrent vulvar cancer. These procedures were analysed in sight of surgical excision, previous therapy, and detailed postoperative results. METHODS: All procedures and clinical parameters were recorded standardized in a data bank and analysed using statistical methods. RESULTS: In 123 local (cutaneous or fasciocutaneous) and 84 regional (myocutaneous) flaps we found a primary healing in about 2/3 of the cases. Local flaps exhibited secondary healing in 31 %, regional flaps in 20 %. This often involved the donor sites and generally did not present any permanent problems. Pronounced healing disturbances (necrosis of more than 10 %) was not achieved in local flaps, in regional flaps it aroused in 5.9 %. Gluteal femoral flaps were used most frequently and showing the best results of all myocutaneous flaps. They were comparable with the local reconstructions by a high degree of reliability and healing. In 15 cases a tissue-loss was observed. In these patients, elevated risk factors, certain oncological characteristics and technical problems could be demonstrated. CONCLUSION: Plastic surgery enlarges the spectrum of operative therapy of vulvar cancer, especially in extensive or recurrent tumors, leading to a favourable oncological outcome and good cosmetic results. Severe healing disturbances are rare and can be controlled.

Adult↗

Low serum 25-hydroxyvitamin D concentrations are associated with insulin resistance and obesity in women with polycystic ovary syndrome.

Insulin resistance (IR) and central obesity are common features of the polycystic ovary syndrome (PCOS). Vitamin D is thought to play a role in the pathogenesis of type 2 diabetes by affecting insulin metabolism. The aim of our study was to investigate the effect of 25-hydroxyvitamin D (25-OH-VD) on metabolic parameters and IR in PCOS. In 120 untreated PCOS patients (median age 28 years) levels of 25-OH-VD (radioimmunoassay method provided by DiaSorin), calcium and anorganic phosphate were measured. In addition, endocrine and metabolic variables were evaluated and a glucose tolerance test was performed to assess indices of IR. In the entire PCOS cohort, 25-OH-VD concentrations were negatively correlated with body mass index (r=-0.2765), body fat (r=-0.2490), HOMA-IR (r=-0.1947), hyperinsulinemia (r=-0.1892) and leptin levels (r=-0.2834), and positively correlated with HDL cholesterol (r=0.2630) (all p<0.05). Subgroup analysis of lean, overweight and obese women revealed significant higher 25-OH-VD levels in lean women. Differences remained significant when women were divided according to their 25-OH-VD levels. Women with hypovitaminosis D (<9 ng/ml) had higher mean BMI, indices of IR and leptin levels compared to women with normal serum levels (all p<0.05). Analysis of vitamin D and biochemical endocrine PCOS features revealed a significant correlation only between 25-OH-VD and sex hormone-binding globulin as well as the free androgen index. In conclusion, in PCOS women, low 25-OH-VD levels are associated with obesity and insulin resistance but not with PCOS per se.

Adolescent↗

Elevated serum levels of calcium-binding S100 proteins A8 and A9 reflect disease activity and abnormal differentiation of keratinocytes in psoriasis.

BACKGROUND: The expression of calcium-binding S100 molecules organized within the epidermal differentiation complex on chromosome 1q21 is disturbed in hyperproliferative skin diseases such as psoriasis. OBJECTIVES: We studied whether serum levels of S100 proteins A8 (S100A8) and A9 (S100A9) are elevated in psoriasis, correlated their amounts with disease activity and identified potential cellular sources. METHODS: Serum obtained from psoriasis patients or from healthy individuals was studied for S100A8 and S100A9 levels by enzyme-linked immunosorbent assay. Data were correlated to disease activity as reflected by the Psoriasis Area and Severity Index (PASI). Cellular sources of S100A8 and S100A9 were identified by in situ hybridization and immunohistochemistry of lesional psoriatic and nonlesional, nonpsoriatic skin. RESULTS: A significant increase of S100A8/S100A9 serum levels was found in patients with psoriasis compared with healthy controls. Grading the patients into two groups of severity, individuals with a PASI of <15 showed serum levels of 705+/-120 ng mL-1 (mean+/-SEM, n=18), those with a PASI of >or=15 showed levels of 1315+/-150 ng mL-1 (n=32) while controls presented with 365+/-50 ng mL-1. Performing in situ hybridization of lesional psoriatic skin we detected a dramatic induction of both S100A8 and S100A9 mRNA and protein primarily in the suprabasal layers of the epidermis while expression was negligible in nonlesional, nonpsoriatic interfollicular epidermis. CONCLUSIONS: Our data demonstrate that hyperproliferation and abnormal differentiation of psoriatic skin is associated with a massive upregulation and secretion of S100A8 and S100A9, suggesting not only a prominent role of these molecules during intracellular calcium-dependent signalling but also implying distinct extracellular functions.

Acute Disease↗

FACS technology used in a new rapid bacterial detection method.

Culture methods for bacterial detection (BacT/ALERT or Pall eBDS) are currently implemented in blood donor screening procedures in many countries. Experience in the first years after implementation of these detection assays showed that although the analytical sensitivity was extremely high (about 1 CFU mL(-1)), the majority of these platelets were still transfused before a positive screening result was attained. Rapid technologies were developed to more effectively prevent transfusion-transmitted bacterial infection. In this study, a new rapid bacterial detection method based on fluorescence-activated cell sorting (FACS) technology was developed. Bacteria were stained with thiazole orange dye for 5 min and measurement was taken immediately after staining. The entire process took only 30 min. Six transfusion-relevant bacteria strains were tested in a spiking study. Without pre-incubation in a special bacteria growth medium, analytical sensitivity ranged between 10(5) CFU mL(-1) (Klebsiella oxytoca and Serratia marcesens) and 10(3) CFU mL(-1) (Escherichia coli). Sensitivity could be improved to 10(1) CFU mL(-1) for all tested bacteria by adding a pre-incubation step (6 h at 37 degrees C). Although preliminary in nature, results of our study suggest that bacterial detection by FACS technology in conjunction with a pre-incubation step offers a sensitive alternative technology to culture methods. Additionally, it provides the benefit of a rapid test time and the opportunity of preventing bacterial transmitted infections more effectively.

Bacteriological Techniques↗

Cytokine and Ig-production by CG-containing sequences with phosphorodiester backbone and dumbbell-shape.

BACKGROUND: Immunostimulatory oligodeoxynucleotides (CpG-ODN) usually contain phosphorothioate (PS) backbones for nucleotide protection, which may result in some nonspecific side-effects like prolongation of coagulation time. OBJECTIVE: The aim of the present study was to investigate the immunomodulatory potential of DNA molecules without PS backbones. Thus, we designed phosphorodiester (PO) molecules with a dumbbell-like covalently-closed structure (dSLIM-30L1). METHODS: We analyzed their effects on peripheral blood mononuclear cells (PBMC) from spontaneous high and low immunoglobulin (Ig)E producer (allergic and nonallergic donors) in comparison with linear CpG-ODN (lin-30L1) with PS backbones, using enzyme-linked immunosorbent assay and flow cytometry. RESULTS: We observed a decrease of spontaneous IgE levels in PBMC from high IgE producer of approximately 27% with both dSLIM-30L1 and lin-30L1. In addition, both molecules enhanced the production of IgA, IgM and IgG1/IgG2, but with a slightly different pattern. Both molecules stimulated the secretion of the T(H)1-like cytokines interleukin (IL)-2, interferon-gamma and IL-12p40 and the pro-inflammatory cytokine IL-6. The immunomodulatory potential of dSLIM-30L1 and lin-30L1 was also effective in PBMC from nonallergic donors, as was confirmed for IL-2, IL-12p40, IgG1/IgG2 and IgM. CONCLUSION: Our data show an inhibition of IgE production but also enhancement of the inflammatory cytokine response in PBMC from allergic and nonallergic donors by covalently-closed PO-based dSLIM-30L1 with a pattern similar to that of linear PS-based lin-30L1, while avoiding PS-modifications and thus PS-mediated side-effects. Whether such molecules are useful for the treatment of allergic diseases will need further clarification by appropriate in vivo studies.

Adult↗

HLA-DRB1*0826 and HLA-DQB1*0627, two novel class II alleles identified in blood stem cell donors of Caucasian origin.

This report describes two novel HLA class II alleles, HLA-DRB1*0826 and HLA-DQB1*0627, that have been identified in two unrelated voluntary blood stem cell donors of Caucasian origin. HLA-DRB1*0826 is characterized by a nucleotide substitution (G to T) in exon 2 at position 163, leading to an amino acid exchange from argenine to leucine. The donor phenotype is HLA-A*0301,*2902; B*3501,*4403; Cw*0401,*1601; DRB1*0101,*0826; DQB1*0402, *0501. The HLA-DQB1*0627 alleles contain a nucleotide substitution at position 184 (T to C) resulting in an amino acid exchange from tyrosine to histidine. Family segregation analysis revealed that the HLA-DQB1*0627 allele belongs to the haplotype A*0101, B*1517, Cw*0701, DRB1*1302, DQB1*0627. The donor phenotype is HLA-A*0101; B*0801,*1517; Cw*0701; DRB1*1302,*1501; DQB1*0602,*0627.

Alleles↗

Fluorescence quencher improves SCANSYSTEM for rapid bacterial detection.

BACKGROUND AND OBJECTIVES: The optimized scansystem could detect contaminated platelet products within 24 h. However, the system's sensitivity was reduced by a high fluorescence background even in sterile samples, which led to the necessity of a well-trained staff for confirmation of microscope results. MATERIALS AND METHODS: A new protocol of the optimized scansystem with the addition of a fluorescence quencher was evaluated. Pool platelet concentrates contaminated with five transfusion-relevant bacterial strains were tested in a blind study. RESULTS: In conjunction with new analysis software, the new quenching dye was able to reduce significantly unspecific background fluorescence. Sensitivity was best for Bacillus cereus and Escherichia coli (3 CFU/ml). DISCUSSION: The application of a fluorescence quencher enables automated discrimination of positive and negative test results in 60% of all analysed samples.

Bacteriological Techniques↗

Anti-HBc screening of blood donors: a comparison of nine anti-HBc tests.

BACKGROUND AND OBJECTIVES: Since voluntary introduction of hepatitis B virus (HBV) minipool nucleic acid amplification technology (NAT) at the German Red Cross, the expected residual risk of a transfusion-associated HBV infection has been estimated to be 1 : 500,000 - about 10 times higher than for human immunodeficiency virus (HIV) or hepatitis C virus (HCV) infection. Donors demonstrating chronic positivity for antibody to hepatitis B core antigen (anti-HBc), negativity for hepatitis B surface antigen (HBsAg) and polymerase chain reaction (PCR)-negative with a low virus load are a major cause of this increased risk. MATERIALS AND METHODS: Ten-thousand blood donors from our blood-donation centre were screened for anti-HBc using the current PRISM HBc and the new PRISM HBcore assay to evaluate the diagnostic sensitivity and specificity of these tests. PRISM HBc- or PRISM HBcore-reactive samples were further analysed using seven additional tests for anti-HBc, two tests for antibody to hepatitis B surface antigen (anti-HBs), one test for antibody to hepatitis B envelope antigen (anti-HBe) and three HBV NAT assays. RESULTS: From a total of 10,000 donors, nine and 14 samples were reactive only in the PRISM HBc and the PRISM HBcore, respectively, whereas 165 samples were reactive in both anti-HBc assays. Further analysis of these 188 anti-HBc-reactive specimens in a total of nine different anti-HBc assays revealed concordant results for 162 (86.2%) specimens. Sample cut-off values for anti-HBc were significantly (P < 0.01) lower for anti-HBc-only reactive samples compared with specimens that were also reactive for anti-HBs or anti-HBe. CONCLUSIONS: Both PRISM anti-HBc assays revealed that approximately 1.8% of non-prescreened blood donors from Germany were reactive for anti-HBc. Although sensitivity was comparable between both assays, specificity was increased significantly with the PRISM HBcore. High anti-HBc sample cut-off values were indicative for reactivity in other HBV parameters and for concordant results in the nine different anti-HBc assays. Look-back investigations are necessary to estimate the infection risk both of anti-HBc-only positive and of anti-HBc/anti-HBs-positive blood transfusions.

Blood Donors↗

NOD mouse model for Sjögren's syndrome: lack of longitudinal stability.

OBJECTIVES: The non-obese diabetic (NOD) mouse is not only a widely used model for diabetes mellitus type I, but also for the chronic autoimmune disease Sjögren's syndrome (SS), mainly affecting salivary and lacrimal glands. We studied the efficacy of local recombinant serotype 2 adeno-associated viral (rAAV2) vector transfer of immunomodulatory transgenes to alter the SS-like disease in NOD mice. Data collected over a 2-year period indicated a changing SS phenotype in these mice and this phenomenon was investigated. METHODS: 10(10) particles rAAV2LacZ/gland were delivered to both submandibular glands (SMGs) of NOD/LtJ mice at 8 weeks (before sialadenitis onset) of age. Salivary flow rates were determined at 8 weeks and time of killing. Blood glucose levels and body weights were measured weekly. After killing, saliva and SMGs were harvested. Analyses of salivary output, inflammatory infiltrates (focus score), SMG cytokine profile, body weight, and diabetes mellitus status were performed. Data from six different experimental studies over 2 years were analyzed and compared. RESULTS: Salivary flow rate, focus score, and SMG cytokines interleukin (IL)-2, IL-4, IL-6, IL-10, IL-12(p70), tumor necrosis factor-alpha and IFNgamma showed changes over time. There were no differences for body weight, diabetes mellitus prevalence, or blood glucose level of non-diabetic mice. CONCLUSION: This retrospective report is the first to describe longitudinal variability in the NOD mouse as a model for SS. We advise other investigators to continuously monitor the SS phenotype parameters and include appropriate controls when studying this disease in NOD mice.

Analysis of Variance↗

[Hormone replacement therapy: curse or blessing?].

There is a controversial discussion on the risks and benefits of hormonal replacement therapy (HRT), and many women and doctors have revised their opinions of HRT over the last few years. Complementary and alternative therapies can be considered an option to treat menopausal symptoms. The following issue summarizes the actual knowledge of treatment options of menopausal symptoms.

Adult↗

[The benefits and risks of hormonal replacement therapy--an update].

Hormonal replacement therapy (HRT) with estrogens and gestagens has been used for more than 40 years in the treatment of menopausal complaints and can be considered an effective treatment for vaso-vegetative symptoms and urogenital atrophy. During the past few years many women and doctors have revised their opinions of HRT. The reasons for this change of view are mainly three large international studies: the Heart and Estrogen/Progestin Study, the Women's Health Initiative Study and the One Million Women Study. In this review we summarize the data from the most important studies and point out the actual status of the controversial discussion on the benefits and risks of HRT.

Adult↗

[Therapy for non-toxic multinodular goiter: radioiodine therapy as attractive alternative to surgery].

UNLABELLED: The need for therapy for nodular goiter results from the growth of thyroid nodules over decades and from the possibility of tracheal compression and worsening of respiratory function. Given the high prevalence of non-toxic goiter, the epidemiologically low incidence of clinically apparent thyroid cancer justifies non-surgical strategies. Randomised studies have shown that levothyroxine offers limited therapeutic effects and is inferior to radioiodine therapy regarding goiter shrinkage. When indication for a definitive therapy is given, the choice between resection and radioiodine therapy should consider volume of goiter, severity of clinical symptoms, thyroid uptake, patient's age, co-morbidity, previous resection of goiter, patient's profession and patient's wish. Even in large goiters between 100 and 300 ml radioiodine therapy showed consistent results with goiter size reduction from 35-40% one year and 40-60% two years after radioiodine therapy. Thyroid hormones to prevent recurrence of goiter are not necessary. Recurrent goiters were seldom observed after radioiodine therapy and resulted from initially very large goiters or uptake in dominate nodules or from low (131)I activities. Recombinant human TSH (rhTSH) offers the opportunity to enhance the effect of radioiodine therapy. Observational studies have shown that rhTSH increases low (131)I uptake in case of high alimentary iodine-supply by the factor 4, causes a more homogenous (131)I distribution within the goiter and improves goiter reduction. A phase I study for dose finding is running in the USA. CONCLUSION: Radioiodine therapy for shrinkage of large non-toxic goiter should not be restricted to elderly patients, or to patients with co-morbidity or high operative risk, but is an attractive alternative to surgery in patients with special professions (singer, teacher, speaker) or with the wish for a non-invasive treatment modality.

Aged↗

A convenient TLC method for the identification of local anesthetics.

A TLC method for the separation of seven local anesthetics and the related antiarrhythmic drug procainamide was developed. Spraying the plates with cobalt(II) thiocyanate solution, followed by spraying with Ehrlich's reagent allowed a clear distinction between the drugs, except for the couple articaine/prilocaine. Articaine could be distinguishedfrom prilocaine and other local anesthetics by a colour reaction with copper(II) sulphate solution.

Anesthetics, Local↗

The level of antibody against E6 HPV 16 oncoprotein in blood sera of women with chronic HPV 16 infection and cervical cancer.

UNLABELLED: The aim of this study was to estimate of the role of chronic HPV 16 infection and the presence of anti E6 HPV 16 in the initiation of the cancerogenesis process of cervical cancer. MATERIAL AND METHODS: The study included two groups of patients. The first group comprised 323 women observed for three consecutive years (1998-2000), in whom the presence of HPV 16 viruses was estimated by PCR, and the level of anti E6 HPV 16 antibodies was estimated in the plasma with ELISA. A similar test was performed in a group of 46 patients with cervical intraepithelial neoplasia (CIN), 91 patients with invasive cervical cancer and 22 women after hysterectomy and RTG-therapy. RESULTS: In 32 patients, chronic HPV 16 infection showed a steady rise in the mean absorbance level of anti E6 HPV 16 antibodies from 0.04 in 1998 to 0.06 in 2000, while in HPV-negative women the mean absorbance value was 0.03-0.04. Mean absorbance value in patients with CIN III and invasive cancer rose with advancing stage of the cancer process and lowered after completion of oncological treatment. The values were 0.14, 0.33 and 0.13, respectively. CONCLUSION: The persistence of chronic HPV 16 infection and accompanying steady rise in absorbance index caused by an increase in the level of antiviral antibodies are a clear warning signal preceding in time the histological process of cancerogenesis.

Adult↗