Relevant data on the distribution of color cones are summarized, with special emphasis on the marked dorsoventral asymmetries observed in a number of mammalian species. In addition, an overview is given of studies that demonstrate the coexistence of two visual pigments within the same cone cell. The biological significance of these phenomena is discussed in conjunction with comparative immunocytochemical analyses of subprimate retinas. Based on various cone distribution patterns and temporal and spatial visual pigment coexpression, two models of cone photoreceptor differentiation are suggested.
The value of ultrasound examinations depends heavily on the preparation of the personnel carrying out the examination and the technical capabilities of the equipment they use. Only well-organized regional or national programs are able to provide high level, cost-effective care based on certification of quality. Such certification must include the training of professionals, the definition of competence levels, accreditation of laboratories and the establishment of professional protocols. Together, these factors can guarantee the standard of care and provide legal protection for practitioners. It is worth carrying out routine screening in each pregnancy because the majority of abnormalities occur in pregnancies with low risk. Abnormalities detected on screening cases and the examination of high risk groups should be referred to higher level centers. Here, appropriate technical background and qualified personnel are present to provide cost-effective care. At the same time, necessary invasive interventions can also be performed. A minimum of three screening tests should be performed during pregnancy. The first should be performed at the fetal age of 10-14 weeks to detect abnormalities and pathological conditions in early pregnancy. The second one has to be performed between the fetal ages of 18 and 22 weeks to assess detailed fetal anatomy and rate of development. The third should be performed between the fetal age of 30 and 34 weeks to assess fetal anatomy, rate of development, placentation and circulation. It is worth considering a fourth screening at approximately 36-38 weeks to assess the intrauterine condition of the fetus and determine the appropriate method of delivery. Finally, besides improving the standard of living, education, and hygienic conditions in developing countries, developed countries also have to help improve the standard of pregnancy care. Within this context, the dissemination of diagnostic ultrasound must be given special emphasis.
It was hypothesized that analysis of global gene expression in ovarian carcinoma can identify dysregulated genes that can serve as molecular markers and provide further insight into carcinogenesis and provide the basis for development of new diagnostic tools as well as new targeted therapy protocols. By applying bioinformatics tools for screening of biomedical databases, a gene expression profile databank, specific for ovarian carcinoma, was constructed with utilizable data sets published in 28 studies that applied different array technology platforms. The data sets were divided into four compartments: (i) genes associated with carcinogenesis: in 14 studies, 1881 genes were extracted, 75 genes were identified in more than one study, and only 4 genes (PRKCBP1, SPON1, TACSTD1, and PTPRM) were identified in three studies. (ii) Genes associated with histologic subtypes: in four studies, 463 genes could be identified, but none of them was identified in more than a single study. (iii) Genes associated with therapy response: in seven studies, 606 genes were identified from which 38 were differentially regulated in at least two studies, 3 genes (TMSB4X, GRN, and TJP1) in three studies, and 1 gene (IFITM1) in four studies. (iv) Genes associated with prognosis and progression: 254 genes were found in seven studies. From these genes, merely three were identified in at least two different studies. This snapshot of available gene expression data not only provides independently described potential diagnostic and therapeutic targets for ovarian carcinoma but also emphasizes the drawbacks of the current state of global gene expression analyses in ovarian cancer.
Transcriptomic analysis of global gene expression in ovarian carcinoma can identify dysregulated genes capable to serve as molecular markers for histology subtypes and survival. The aim of our study was to validate previous candidate signatures in an independent setting and to identify single genes capable to serve as biomarkers for ovarian cancer progression. As several datasets are available in the GEO today, we were able to perform a true meta-analysis. First, 829 samples (11 datasets) were downloaded, and the predictive power of 16 previously published gene sets was assessed. Of these, eight were capable to discriminate histology subtypes, and none was capable to predict survival. To overcome the differences in previous studies, we used the 829 samples to identify new predictors. Then, we collected 64 ovarian cancer samples (median relapse-free survival 24.5 months) and performed TaqMan Real Time Polimerase Chain Reaction (RT-PCR) analysis for the best 40 genes associated with histology subtypes and survival. Over 90% of subtype-associated genes were confirmed. Overall survival was effectively predicted by hormone receptors (PGR and ESR2) and by TSPAN8. Relapse-free survival was predicted by MAPT and SNCG. In summary, we successfully validated several gene sets in a meta-analysis in large datasets of ovarian samples. Additionally, several individual genes identified were validated in a clinical cohort.With $43,000 cases in Europe and $22,000 cases in the United States of America each year, ovarian carcinoma is the eighth most frequent malignant tumor in the female population. Although some improvements were achieved in the 5-year survival due to improved efficiency of surgery and treatment with empirically optimized combinations of cytotoxic drugs, the overall cure rate today remains as low as 30%. The most likely explanation for this is the high heterogeneity of ovarian carcinomas.Subtypes of ovarian cancer are recognized based on grade and on histologic subtypes. While high-grade malignancies grow rapidly, are relatively chemosensitive and evolve without a definitive precursor lesion, low-grade tumors grow more slowly, are more resistant to chemotherapy and share molecular characteristics with other low-malignant potential neoplasms. 1 Expression profiling studies have shown that high-grade tumors cluster separately from low-grade carcinomas and borderline tumors. 2,3 About 90% of epithelial ovarian cancers are clonal. 4 This is also reflected in their classification into four different main histotypes of high-grade serous (resembling normal cells of the fallopian tube), endometrioid (cells of the endometrium), mucinous (endocervix) and clear cell (vagina) cancers. The correlation between the different subtypes and their precursor cells were already confirmed by altered gene expression patterns. 5 These subtypes show further differences regarding their epidemiology, genetic changes, gene expression, tumor markers and chemotherapy response. Meanwhile, similarities were also described between high-grade sero...
1. Glycine conjugation of benzoic acid was investigated in anaesthetized rats by measuring the disappearance of benzoate from blood, and the appearance of benzoylglycine in blood and urine. 2. Administration of glycine (1-10 mmol/kg,i.v.) increased the capacity of benzoylglycine formation in a dose-dependent fashion, with a maximal rate (8.1 mumol/kg per min) occurring after administration of 5 mmol/kg glycine. The normal endogenous glycine supply (1.7 mM in liver) permits glycine conjugation only at an approximate half-maximal rate (4.5 mumol/kg/per min). 3. The increase in benzoylglycine formation in response to exogenous glycine supply is also a function of the benzoate dosage. Decreased responsiveness at high benzoate dosage indicates that the availability of coenzyme A is another factor that also limits the capacity of glycine conjugation. 4. Cysteamine (200 mg/kg, i.p.), a potent inhibitor of the mitochondrial glycine cleavage system, rapidly increased hepatic glycine concentration 2-3-fold without affecting the concentration of the other co-substrates (i.e. coenzyme A and ATP) of glycine conjugation. 5. Administration of cysteamine increased the blood clearance of benzoate by 50%, the appearance of benzoylglycine in blood, and the urinary excretion of benzoylglycine. 6. It is concluded that the activity of glycine cleavage system is an important determinant of glycine supply and, thereby, the capacity of glycine conjugation of xenobiotics.
Opening the uterine cavity does not impair postoperative pregnancy rates. Preoperative location, size and number of fibroids do not influence postoperative reproductive results.
The endocannabinoid system contributes to the regulation of appetite, food intake and energy balance. Fatty acid amide hydrolase is responsible for degradating anandamide, a key messenger of the endocannabinoid system. C385A is a common, functionally active genetic polymorphism of the gene encoding fatty acid amide hydrolase and has been associated with overweight and obesity. Our aim was to establish whether single nucleotide polymorphism C385A has an association with polycystic ovary syndrome or its clinical features.A monocentric pilot study was performed on 63 patients with polycystic ovary syndrome and 67 healthy control subjects. Anthropometric parameters and laboratory data were acquired from subjects. The alleles of the polymorphism were detected using polymerase chain reaction and subsequent cleavage by Eco130I (StyI) restriction endonuclease verified by direct DNA sequencing.No difference was found in minor allele frequency between patient and control groups. Those patients, carrying the C385A polymorphism were associated with higher free thyroxine hormone levels. In the control group, carriers of the polymorphism had significantly lower insulin levels.Our data indicate that the C385A polymorphism of the fatty acid amide hydrolase gene is not a genetic susceptibility factor for the development of polycystic ovary syndrome. However, the polymorphism might have a role in influencing the synthesis or metabolism of different hormones including thyroxin and insulin.
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