128 research outputs found

    Animal models for aberrations of gonadotropin action

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    During the last two decades a large number of genetically modified mouse lines with altered gonadotropin action have been generated. These mouse lines fall into three categories: the lack-of-function mice, gain-of-function mice, and the mice generated by breeding the abovementioned lines with other disease model lines. The mouse strains lacking gonadotropin action have elucidated the necessity of the pituitary hormones in pubertal development and function of gonads, and revealed the processes from the original genetic defect to the pathological phenotype such as hypo- or hypergonadotropic hypogonadism. Conversely, the strains of the second group depict consequences of chronic gonadotropin action. The lines vary from those expressing constitutively active receptors and those secreting follicle-stimulating hormone (FSH) with slowly increasing amounts to those producing human choriogonadotropin (hCG), amount of which corresponds to 2000-fold luteinizing hormone (LH)/hCG biological activity. Accordingly, the phenotypes diverge from mild anomalies and enhanced fertility to disrupted gametogenesis, but eventually chronic, enhanced and non-pulsatile action of both FSH and LH leads to female and male infertility and/or hyper- and neoplasias in most of the gonadotropin gain-of-function mice. Elevated gonadotropin levels also alter the function of several extra-gonadal tissues either directly or indirectly via increased sex steroid production. These effects include promotion of tumorigenesis in tissues such as the pituitary, mammary and adrenal glands. Finally, the crossbreedings of the current mouse strains with other disease models are likely to uncover the contribution of gonadotropins in novel biological systems, as exemplified by the recent crossbreed of LHCG receptor deficient mice with Alzheimer disease mice

    In utero exposure to cigarette chemicals induces sex-specific disruption of one-carbon metabolism and DNA methylation in the human fetal liver

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    Background: Maternal smoking is one of the most important modifiable risk factors for low birthweight, which is strongly associated with increased cardiometabolic disease risk in adulthood. Maternal smoking reduces the levels of the methyl donor vitamin B12 and is associated with altered DNA methylation at birth. Altered DNA methylation may be an important mechanism underlying increased disease susceptibility; however, the extent to which this can be induced in the developing fetus is unknown. Methods: In this retrospective study, we measured concentrations of cobalt, vitamin B12, and mRNA transcripts encoding key enzymes in the 1-carbon cycle in 55 fetal human livers obtained from 11 to 21 weeks of gestation elective terminations and matched for gestation and maternal smoking. DNA methylation was measured at critical regions known to be susceptible to the in utero environment. Homocysteine concentrations were analyzed in plasma from 60 fetuses. Results: In addition to identifying baseline sex differences, we found that maternal smoking was associated with sex-specific alterations of fetal liver vitamin B12, plasma homocysteine and expression of enzymes in the 1-carbon cycle in fetal liver. In the majority of the measured parameters which showed a sex difference, maternal smoking reduced the magnitude of that difference. Maternal smoking also altered DNA methylation at the imprinted gene IGF2 and the glucocorticoid receptor (GR/NR3C1). Conclusions: Our unique data strengthen studies linking in utero exposures to altered DNA methylation by showing, for the first time, that such changes are present in fetal life and in a key metabolic target tissue, human fetal liver. Furthermore, these data propose a novel mechanism by which such changes are induced, namely through alterations in methyl donor availability and changes in 1-carbon metabolism

    The Relevance of Breast Cancer Subtypes in the Outcome of Neoadjuvant Chemotherapy

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    BACKGROUND: Breast cancer is increasingly considered a heterogeneous disease. The aim of this study was to assess the differences between histological and receptor-based subtypes in breast-conserving surgery and pathological complete response (pCR) after neoadjuvant chemotherapy. METHOD: A consecutive series of 254 patients with operable breast cancer treated with neoadjuvant chemotherapy was analyzed. Tumors were classified according to their receptor status in estrogen receptor (ER)-positive tumors (HER2-negative), triple-negative tumors, and HER2-positive tumors. The type of surgery feasible prior to neoadjuvant chemotherapy was compared with the actual surgery performed. RESULTS: The overall increase in breast-conserving surgery was 37% (73 of 198). In patients with ductal and lobular carcinomas this increase was 41% (63 of 152, 95% confidence interval [95% CI] 0.34-0.49) and 20% (7 of 35, 95% CI 0.10-0.36), respectively (P = 0.02). Half of the patients with lobular carcinoma had to undergo a secondary mastectomy because of incomplete resection margins. In ER-positive, triple-negative and HER2-positive tumors, the increase in breast-conserving surgery was 39% (42 of 109, 95% CI 0.30-0.48), 24% (11 of 45, 95% CI 0.14-0.38), and 45% (20 of 44, 95% CI 0.32-0.60) (P = 0.11). The pCR rate in ductal and lobular carcinomas was 12% (23 of 195) and 2% (1 of 42), respectively (P = 0.09). In ER-positive, triple-negative and HER2-positive tumors the pCR rates were 2% (3 of 138), 28% (16 of 57), and 18% (10 of 56), respectively. Multivariate analysis showed that the receptor-based subtype was the only significant predictor of pCR (P = 0.004). CONCLUSION: In lobular tumors the benefit with regard to breast-conserving surgery of neoadjuvant chemotherapy is questionable. Although in ER-positive tumors the pCR rate is low, the increase in breast-conserving surgery was remarkable in ductal ER-positive tumor

    Sexual Abuse-Current Medico-legal, Forensic and Psychiatric Aspects

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    Abstract Violence against women and minors is a worldwide problem that has not yet been sufficiently acknowledged. There are many obstacles especially when sexual abuses have to be evaluated. These problems are present both when victims of sexual abuse are evaluated and when sex offenders are dealt with, especially when the offenders are juvenile sex offenders (JSO). These issues give cause for great concern about prognosis, and the resulting psychosocial implications, and call for a special effort from the scientific community in identifying appropriate prevention and treatment methods. This chapter is divided into two parts. The first part deals with the forensic and psychiatric features, such as diagnostic and therapeutic/rehabilitative strategies for JSO, while the second part analyzes the legal–medicine aspects related to rape/sexual assault in a European context

    Cellular pharmacology of multi- and duplex drugsconsisting of ethynylcytidine and 5-fluoro-2′-deoxyuridine

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    Prodrugs can have the advantage over parent drugs in increased activation and cellular uptake. The multidrug ETC-L-FdUrd and the duplex drug ETC-FdUrd are composed of two different monophosphate-nucleosides, 5-fluoro-2′deoxyuridine (FdUrd) and ethynylcytidine (ETC), coupled via a glycerolipid or phosphodiester, respectively. The aim of the study was to determine cytotoxicity levels and mode of drug cleavage. Moreover, we determined whether a liposomal formulation of ETC-L-FdUrd would improve cytotoxic activity and/or cleavage. Drug effects/cleavage were studied with standard radioactivity assays, HPLC and LC-MS/MS in FM3A/0 mammary cancer cells and their FdUrd resistant variants FM3A/TK−. ETC-FdUrd was active (IC50 of 2.2 and 79 nM) in FM3A/0 and TK− cells, respectively. ETC-L-FdUrd was less active (IC50: 7 nM in FM3A/0 vs 4500 nM in FM3A/TK−). Although the liposomal formulation was less active than ETC-L-FdUrd in FM3A/0 cells (IC50:19.3 nM), resistance due to thymidine kinase (TK) deficiency was greatly reduced. The prodrugs inhibited thymidylate synthase (TS) in FM3A/0 cells (80–90%), but to a lower extent in FM3A/TK− (10–50%). FdUMP was hardly detected in FM3A/TK− cells. Inhibition of the transporters and nucleotidases/phosphatases resulted in a reduction of cytotoxicity of ETC-FdUrd, indicating that this drug was cleaved outside the cells to the monophosphates, which was verified by the presence of FdUrd and ETC in the medium. ETC-L-FdUrd and the liposomal formulation were neither affected by transporter nor nucleotidase/phosphatase inhibition, indicating circumvention of active transporters. In vivo, ETC-FdUrd and ETC-L-FdURd were orally active. ETC nucleotides accumulated in both tumor and liver tissues. These formulations seem to be effective when a lipophilic linker is used combined with a liposomal formulation

    Relationship between Antibody Susceptibility and Lipopolysaccharide O-Antigen Characteristics of Invasive and Gastrointestinal Nontyphoidal Salmonellae Isolates from Kenya

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    Background: Nontyphoidal Salmonellae (NTS) cause a large burden of invasive and gastrointestinal disease among young children in sub-Saharan Africa. No vaccine is currently available. Previous reports indicate the importance of the O-antigen of Salmonella lipopolysaccharide for virulence and resistance to antibody-mediated killing. We hypothesised that isolates with more O-antigen have increased resistance to antibody-mediated killing and are more likely to be invasive than gastrointestinal. Methodology/Principal findings: We studied 192 NTS isolates (114 Typhimurium, 78 Enteritidis) from blood and stools, mostly from paediatric admissions in Kenya 2000-2011. Isolates were tested for susceptibility to antibody-mediated killing, using whole adult serum. O-antigen structural characteristics, including O-acetylation and glucosylation, were investigated. Overall, isolates were susceptible to antibody-mediated killing, but S. Enteritidis were less susceptible and expressed more O-antigen than Typhimurium (p\u3c0.0001 for both comparisons). For S. Typhimurium, but not Enteritidis, O-antigen expression correlated with reduced sensitivity to killing (r = 0.29, 95% CI = 0.10-0.45, p = 0.002). Both serovars expressed O-antigen populations ranging 21-33 kDa average molecular weight. O-antigen from most Typhimurium were O-acetylated on rhamnose and abequose residues, while Enteritidis O-antigen had low or no O-acetylation. Both Typhimurium and Enteritidis O-antigen were approximately 20%-50% glucosylated. Amount of S. Typhimurium O-antigen and O-antigen glucosylation level were inversely related. There was no clear association between clinical presentation and antibody susceptibility, O-antigen level or other O-antigen features. Conclusion/Significance: Kenyan S. Typhimurium and Enteritidis clinical isolates are susceptible to antibody-mediated killing, with degree of susceptibility varying with level of O-antigen for S. Typhimurium. This supports the development of an antibody-inducing vaccine against NTS for Africa. No clear differences were found in the phenotype of isolates from blood and stool, suggesting that the same isolates can cause invasive disease and gastroenteritis. Genome studies are required to understand whether invasive and gastrointestinal isolates differ at the genotypic level

    Spinal infection: state of the art and management algorithm

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    Spinal infection is a rare pathology although a concerning rising incidence has been observed in recent years. This increase might reflect a progressively more susceptible population but also the availability of increased diagnostic accuracy. Yet, even with improved diagnosis tools and procedures, the delay in diagnosis remains an important issue. This review aims to highlight the importance of a methodological attitude towards accurate and prompt diagnosis using an algorithm to aid on spinal infection management. METHODS: Appropriate literature on spinal infection was selected using databases from the US National Library of Medicine and the National Institutes of Health. RESULTS: Literature reveals that histopathological analysis of infected tissues is a paramount for diagnosis and must be performed routinely. Antibiotic therapy is transversal to both conservative and surgical approaches and must be initiated after etiological diagnosis. Indications for surgical treatment include neurological deficits or sepsis, spine instability and/or deformity, presence of epidural abscess and upon failure of conservative treatment. CONCLUSIONS: A methodological assessment could lead to diagnosis effectiveness of spinal infection. Towards this, we present a management algorithm based on literature findings

    Gravitational Wave Detection by Interferometry (Ground and Space)

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    Significant progress has been made in recent years on the development of gravitational wave detectors. Sources such as coalescing compact binary systems, neutron stars in low-mass X-ray binaries, stellar collapses and pulsars are all possible candidates for detection. The most promising design of gravitational wave detector uses test masses a long distance apart and freely suspended as pendulums on Earth or in drag-free craft in space. The main theme of this review is a discussion of the mechanical and optical principles used in the various long baseline systems in operation around the world - LIGO (USA), Virgo (Italy/France), TAMA300 and LCGT (Japan), and GEO600 (Germany/U.K.) - and in LISA, a proposed space-borne interferometer. A review of recent science runs from the current generation of ground-based detectors will be discussed, in addition to highlighting the astrophysical results gained thus far. Looking to the future, the major upgrades to LIGO (Advanced LIGO), Virgo (Advanced Virgo), LCGT and GEO600 (GEO-HF) will be completed over the coming years, which will create a network of detectors with significantly improved sensitivity required to detect gravitational waves. Beyond this, the concept and design of possible future "third generation" gravitational wave detectors, such as the Einstein Telescope (ET), will be discussed.Comment: Published in Living Reviews in Relativit
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