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BACKGROUND: Conflicting evidence suggests a possible role for vitamin E in mammalian glucose metabolism and the protection from type 2 diabetes. The alpha-tocopherol transfer protein (alpha-TTP) mediates the transfer of alpha-tocopherol (alpha-TOH) from hepatocytes to very-low-density lipoproteins, thereby controlling plasma levels of alpha-TOH. AIM OF THE STUDY: The aim of this study was to investigate the putative impact of alpha-TTP knock-out on glucose metabolism in mice. METHODS: Mice deficient for alpha-TTP and wild-type control littermates were fed a diet containing 200 mg alpha-tocopheryl acetate per kg to ameliorate alpha-TOH deficiency in knock-out mice. We investigated fasting and postprandial plasma glucose, insulin and triglyceride levels of both groups of mice at different ages. All genotypes and age groups were further subjected to glucose and insulin tolerance tests, and number of insulin-producing islets of Langerhans were determined. RESULTS: Plasma alpha-TOH levels of knock-out mice were 34% the levels of wild-type controls: Any signs of alpha-TOH deficiency were absent at any age. Unexpectedly, serum glucose levels both in the fasted and in the fed state were lower in alpha-TTP-deficient mice at any age. Removal rates for intraperitoneally injected glucose were found to be significantly increased in young alpha-TTP-deficient mice. This improved glucose tolerance was caused by increased insulin secretion in response to an intraperitoneal glucose challenge due to an increased number of pancreatic islets, as well as by increased sensitivity to intraperitoneally injected insulin, both significantly promoting glucose metabolism in alpha-TTP-deficient mice. CONCLUSIONS: Our findings suggest that alpha-TTP-deficiency in states of alpha-TOH supplementation unexpectedly promotes glucose tolerance in mice due to both increased insulin secretion and insulin action, suggesting differential roles of alpha-TTP and alpha-TOH in the pathogenesis of type 2 diabetes mellitus. [ABSTRACT FROM AUTHOR]

The adaption of endothelial cells to local flow conditions is a multifunctional process which leads to distinct alterations in cell shape, the subcellular distribution of structural proteins, and cellular function. G-protein-coupled receptors (GPCRs) have been identified to be fundamentally involved in such processes. Recently, we and others have shown that the expression of the endothelial GPCR apelin receptor (APJ) is regulated by fluid flow and that activation of APJ participates in signaling pathways which are related to processes of mechanotransduction. The present study aims to illuminate these findings by further visualization of APJ function. We show that APJ is located to the cellular junctions and might thus be associated with platelet endothelial cell adhesion molecule-1 (PECAM-1) in human umbilical vein endothelial cells (HUVEC). Furthermore, siRNA-mediated silencing of APJ expression influences the shear-induced adaption of HUVEC in terms of cytoskeletal remodeling, cellular elasticity, cellular motility, attachment, and distribution of adhesion complexes. Taken together, our results demonstrate that APJ is crucial for complemented endothelial adaption to local flow conditions., (© 2018 Wiley Periodicals, Inc.)

3D micropillars generated by photolithography are used as a platform to probe by atomic force microscopy the mechanodynamics of human induced pluripotent stem cell-derived cardiomyocytes. 3D micropillars guide subcellular cytoskeletal modifications of cardiomyocytes and lead to biochemical changes altering beating rate, stiffness, and calcium dynamics of the cells., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Background: HNA-3a antibodies induce severe transfusion-related acute lung injury (TRALI) in which neutrophils play a major role. As neutrophil passage through the pulmonary microvasculature is a critical step in the pathogenesis of TRALI, we investigated the impact of HNA-3a antibodies on two important factors that could impair granulocyte passage through lung capillaries: the elasticity of neutrophils and the expression and activation of adhesion molecules., Study Design and Methods: The impact of HNA-3a antibodies on the elasticity of neutrophils was investigated using atomic force microscopy (AFM). Neutrophils were settled on poly-2-hydroxyethyl-methacrylate-coated glass slides before treatment with anti-HNA-3a plasma samples, control plasma, or control plasma containing formyl-methionyl-leucyl-phenylalanine (fMLP). Elasticity measurements were carried out in a temperature-controlled perfusion chamber using an atomic force microscopy (AFM) device. The impact of HNA-3a antibodies on the surface expression of total CD11b, activation of CD11b, and L-selectin (CD62L) shedding was investigated by flow cytometry. The functional impact of HNA-3a antibodies on neutrophil adhesion was assessed using fibrinogen-coated plates., Results: HNA-3a antibodies induced stiffening of neutrophils (+24%-40%; p < 0.05) to a similar extent as fMLP. This effect was blocked by treatment of neutrophils with cytochalasin D. While total surface expression of CD11b and L-selectin on neutrophils was largely unaffected, HNA-3a antibodies induced alloantigen-specific activation of CD11b (+72%-107%; p < 0.05) and increased adhesion of neutrophils to fibrinogen., Conclusion: Accumulation of neutrophils in the pulmonary microvasculature during severe TRALI is likely mediated by increased rigidity and CD11b-mediated adhesion of neutrophils leading to retention of neutrophils., (© 2015 AABB.)

The use of the simple Hertz model for the analysis of Atomic Force Microscopy (AFM) force-distance curves measured on soft spherical cell-like particles leads to significant underestimations of the objects Young's modulus E. To correct this error, a mixed double contact model (based on the simple Hertz model and the Johnson-Kendall-Roberts (JKR) model) was derived. The model considers two independent particle deformation sites: (i) the upper part of the particle is deformed by the AFM indenter, (ii) the bottom part is deformed by the substrate, which is usually unnoticed. It becomes apparent that for soft particles even small forces between substrate and particle can influence the resulting force-distance curves. For instance we show, that a gravity-induced compression on the particle bottom side can have significant influence on the measurements. To highlight these observations, the deviation of the particle Young's modulus E between the simple Hertz model and our model is calculated. This error strongly depends on the ratio of the three involved radii: (i) the radius of the AFM indenter, (ii) the radius of the particle and (iii) the radius of the substrate as well as on the acting gravity force. Overall, the analysis suggests that for nanoscopic indenters the deviation is negligible, whereas the use of microscopic indenters results in significant errors that can be corrected via the presented model. This is important especially for very soft particles, since larger indenters can achieve higher signal to noise ratios. Furthermore, the applicability of the model was confirmed by indentation experiments on hydrogel microbeads. The mixed double contact model is applicable to a large range of indenter geometries and can be adapted for other contact models.

Background: Ventricular dilation is known as a pivotal predictor in recent-onset cardiomyopathy (ROCM), but its pathophysiology is not fully understood. In the present study we investigated whether single-cell stiffness of right and left ventricular-derived fibroblasts has an effect on cardiac phenotype in patients with ROCM., Methods and Results: Patients with endomyocardial biopsy-proven ROCM were included (n=10). Primary cardiac fibroblasts (CFBs) were cultured from left and right ventricular endomyocardial biopsies and their single-cell stiffness was analyzed by quantification of Young's modulus using colloidal probe atomic force microscopy. Cardiac fibrosis was analyzed by Masson's trichrome staining. CFBs from the left ventricle showed significantly decreased stiffness when compared with CFBs from the right ventricle, indexed by decreased stiffness (Young's modulus 3,374±389 vs. 4,837±690 Pa; P<0.05). Young's modulus of CFBs derived from the left ventricle correlated negatively with the left ventricular end-diastolic dimension derived from 2-dimensional echocardiography (R(2)=0.77; P<0.01). Neither left nor right ventricular fibrosis correlated with the respective ventricular dimensions., Conclusions: Our data suggest that a decrease in single-cell stiffness of left ventricular fibroblasts could trigger left ventricular dilation in patients with ROCM. This implies a new potential mechanism for the ventricular dilation with this disease.

The Cre/loxP-system has become the system of choice for the generation of conditional so-called knockout mouse strains, i.e. the tissue-specific disruption of expression of a certain target gene. We here report the loss of expression of Cre recombinase in a transgenic mouse strain with increasing number of generations. This eventually led to the complete abrogation of gene expression of the inserted Cre cDNA while still being detectable at the genomic level. Conversely, loss of Cre expression caused an incomplete or even complete lack of disruption for the protein under investigation. As Cre expression in the tissue of interest in most cases cannot be addressed in vivo during the course of a study, our findings implicate the possibility that individual tail-biopsy genotypes may not necessarily indicate the presence or absence of gene disruption. This indicates that sustained post hoc analyses in regards to efficacy of disruption for every single study group member may be required.

A repeat Pap smear as well as a smear for human papillomavirus (HPV)-DNA detection with the Hybrid Capture assay (Digene diagnostics/Murex, Burgwedel) were collected from 30 women with Pap smears recurrently classified as "Pap III". All patients underwent colposcopy and histological assessment. The repeat Pap smear distinguished correctly in 15, colposcopy in 19 and the Hybrid Capture assay in 27 cases between neoplastic and inflammatory lesions. All invasive neoplasms were positive for HPV-DNA. HPV typing seems to be a suitable non-invasive method for early selection of cervical lesions that need histological assessment in women with smears classified as "Pap III".

100 patients with CIN on referral Pap and with a distinct cervical lesion on colposcopy were treated with the loop electrosurgical excisional procedure (LEEP). Compared with 60 women who underwent cold-knife conization, the number of lesions classified as CIN-3 or more did not differ between the two groups (53% vs 53.3%). Severe haemorrhage and cervical stenosis were only observed after conization. Involvement of resection margins was found in 18% of all LEEP and in 16.7% of all cone biopsies. 3-12 months after LEEP the rate of cytologically and biopsy proven neoplasia was 2.2%. LEEP is a safe and effective procedure and should be used as the treatment of choice for distinct cervical lesions.

A total of 158 women who either HIV-infected or under iatrogenic immunosuppression were examined regularly during a 4-year period to evaluate if certain vulvar neoplasms and cervical neoplasia have similar associated risk factors. Patients with CIN were matched prospectively with immunocompetent controls with CIN. Forty-eight cervical lesions were detected among patients, including 2 invasive carcinoma and 15 CIN-3 lesions, compared to 11 vulvar lesions, including 2 invasive carcinoma and 7 VIN-3 lesions. Women who have more than five life-time partners were more likely to have HPV-DNA positive cervical swabs and vulvar scrapes as well as cervical and/or vulvar neoplasia. Compared to 2.7% of controls 15.2% of patients with CIN had coexisting high-grade lesions of the vulva. With 1 exception all patients with vulvar neoplasia either suffered from symptomatic immunodeficiency or received immunosuppressive drugs for more than 10 years. Except for 1 VIN-3 lesions, all vulvar neoplasms were associated with HPV-DNA types 16, 31, and/or 33. Six of nine patients as well as the 2 controls with coexisting vulvar and cervical neoplasia had the same HPV-type associated with both lesions. All vulvar lesions were classified as either "warty" or "basaloid". In conclusion cervical and bowenoid/basaloid vulvar neoplasia seem to have a similar HPV-related genesis. Malfunction of the cellular immune response appears to be a cofactor in the genesis of HPV-associated neoplasia at both sites.

In contrast to the broad experience concerning the therapeutic use of carboplatin, only limited data are available regarding the patterns of carboplatin-induced emesis, one of its most distressing side effects. This study reports frequency, severity and time course of carboplatin-induced vomiting and nausea refractory to 5-HT3 antagonism. A total of 216 patients receiving single-day carboplatin-based chemotherapy regimen were enrolled into an open multicenter study focusing on the safety and efficacy of ondansetron 8 mg t.d.s. Emesis on day 1 occurred in 22% and nausea in 75% of the patients; 44% of patients reported some degree of vomiting within the 5 days observation period. The risk for emesis and nausea over 2-5 days was increased in patients suffering from emesis on day 1 (relative risk 2.25 for vomiting and 2.84 for nausea, respectively). The median cumulative number of emetic episodes was 0 for all patients and 4 for the patients who did vomit at least on 1 day. Vomiting began on average 1.77 days following chemotherapy administration. The mean duration of vomiting was 2 days and 3.1 days for nausea. Carboplatin showed a monophasic prolonged pattern of emesis. The combination with cyclophosphamide led to an earlier onset and a higher frequency of vomiting. The analysis of the pattern of emesis refractory to 5-HT3 receptor blockade should help to describe the course of emesis, which is probably triggered through a 5-HT3 receptor-independent mechanisms.

In order to evaluate the maximum tolerable dose of a combination chemotherapy consisting of cyclophosphamide, methotrexate, 5-fluorouracil, and folinate (CMFF), 30 female patients with histopathologically confirmed, previously untreated advanced breast cancer were entered into this pilot study. Chemotherapy consisted of fixed doses for methotrexate (40 mg/m2 i.v. on day 1), 5-fluorouracil (500 mg/m2 i.v. on day 2 to 4) and folinic acid (2 x 200 mg/m2 i.v., 0 + 2 h on day 2 to 4). The dose of cyclophosphamide was escalated stepwise, starting with 200 mg/m2 i.v. on day 2 to 4, to 240 mg/m2, 290 mg/m2, 360 mg/m2 and 400 mg/m2, respectively, for each subsequent five patients. Treatment was repeated every four weeks. A total of 92 treatment cycles was given. Myelosuppression was the dose-limiting toxicity: leukopenia WHO grade III or IV was observed after a total of 28 cycles and anemia of equal intensity after 1 cycle. No thrombocytopenia WHO grade III or IV was recorded. Myelotoxicity increased with higher doses of cyclophosphamide. Among non-hematologic toxicities, alopecia was reported in two-thirds of the patients. Nausea and vomiting was noted in 25% of treatment cycles, but in one cycle only WHO grade III was recorded. No other toxicities exceeding WHO grade II occurred.(ABSTRACT TRUNCATED AT 250 WORDS)

Most cases of low-grade cervical intraepithelial neoplasia (CIN) associated with oncogenic human papillomavirus (HPV) types regress spontaneously within years. Unknown co-factors seem to be necessary for a progression to malignancy. To determine the possible role of cellular immunodeficiency as such a co-factor in the genesis of genital neoplasia, 48 HIV-infected women and 52 allograft recipients were examined periodically during a 3-year period. Colposcopy, cytology and HPV-DNA typing (ViraType) were performed at each visit. Each cervical lesion was matched prospectively with 2 lesions from immunocompetent controls. In all, 29/100 patients suffered from cervical neoplasms, including 2 advanced cervical cancers and 9 CIN3 lesions. Correlation between grade of lesion and HPV DNA 16/18 was significant. Low-grade lesions among patients progressed more often than among controls and recurrent lesions after destructive treatment were seen more frequently among patients than among controls. All patients with CD4-lymphocyte counts of < 400/microliters or immunosuppression for more than 3 years suffered from progressive lesions. We conclude that malfunction of the cellular immune response following either HIV-induced depletion or iatrogenic inhibition of CD4-lymphocyte activation, enhances the progression of HPV-induced cervical lesions to malignancy.

Uterine metastases of extragenital malignomas are rarely presented in literature. Malignant melanoma as primary tumour is described more often than can be expected with regard to its relative incidence in comparison to other malignomas. If the uterus is involved in melanoma disease, mostly cervix and myometrium are affected, endometrial metastases are considered to be very rare. If the primary tumour is known, bleeding abnormalities frequently lead to the diagnosis of uterine metastases, but occasionally abnormal bleeding appears to be the first symptom of melanoma disease. In the following another such case is described and an additional case of endometrial metastases of malignant melanoma is presented.

The malignant melanoma mostly is situated on the skin, the vulva being more often affected then expected in relation to its share in the total body surface. The peak of incidence lies in the fifth and sixth life decade. Five types of the tumor are known: lentigo maligna melanoma, superficial spreading melanoma, nodular melanoma, acrolentiginous melanoma and non-classifiable melanoma. For estimation of prognosis and choice of adequate mode of therapy histopathological examinations with regard to the level of invasion according to Clark and Chung, histomorphometric evaluation of the depth of invasion suggested by Breslow and the pronostic index of Schmoeckel and Braun-Falco are useful. The operative therapy of choice is the extensive tumor excision. In case of extended local invasion radical vulvectomy is indicated, in certain cases combined with inguinal, sometimes even pelvic lymphonodectomy. In inoperable cases radiotherapy may be tried, but success seems to be poor. Polychemotherapy may induce remissions, but hardly a prolongation of survival. New therapy trials are dealing with immunmodulation, mostly using different substances of biological response modifiers. The prognosis of malignant melanoma of the vulva must be considered to be poorer than that of melanomas in other sites of the body, local recurrence is frequent, the five year survival rate being 30-35%. Whether pregnancy does have an effect on melanoma growth is still unknown. Early stages of melanoma disease may be treated without interrupting pregnancy, whereas advanced stages require termination of pregnancy, followed by specific tumor therapy.