Lipotropismus von Coxsackie-Virus (Typ B-1) bei ausgewachsenen weißen Mäusen

Zusammenfassung Im braunen Fettgewebe ausgewachsener und hormonal nicht beeinflußter Mäuse findet eine frühzeitige und intensive Vermehrung von Coxsackie-Virus B- 1 (Stamm KLÍ und CONN- 5) statt. Auf die Bedeutung dieses Befundes für den Mechanismus der Coxsackie-Infeklion der weißen Maus wird hingewiesen.     

Vitamin D metabolism

Vitamin D is the collective name for cholecalciferol (vitamin D3) and ergocalciferol (vitamin D2), which are precursors of hormones with an important role in regulation of the metabolism of calcium and phosphates. This review article describes the production of vitamin D3 in the skin by ultraviolet radiation from sunlight, transport of vitamin D and its metabolites in blood, formation of the active hormonal form - calcitriol (1,25-dihydroxyvitamin D) by hydroxylation in the liver and kidney, and termination of the action by catabolism to inactive metabolites.     

Birth prevalence of neural tube defects: a population-based study in South-Eastern Hungary

Purpose

Primary prevention by periconceptional folic acid supplementation can significantly reduce the risk of neural tube defects. EUROCAT, the European network of population-based registries for the epidemiologic surveillance of congenital anomalies, lacks sufficient data on the birth prevalence of neural tube defects in Hungary before and after the promotion of primary prevention by folic acid. Our aims were to compare the birth prevalence of neural tube defects (myelomeningocele, anencephaly and encephalocele) over two 12-year periods in South-Eastern Hungary. Further aims were to compare our data to those ones in other areas in Europe.

Methods

Data were collected from the databases of the Department of Hungarian Congenital Abnormality Registry. The total and live birth prevalence rate of neural tube defects were calculated and compared over 1980–1991 and 1994–2005. In addition, the trends in the total birth prevalence, the number of live births and terminations for and stillbirths with neural tube defects were analysed throughout the period of 1994–2005.

Results

A significant decline was found in the total and live birth prevalence of myelomeningocele, anencephaly and encephalocele over 1994–2005 compared to the period of 1980–1991. The total birth prevalence of neural tube defects, however, showed a trend of increase after 1994, with declining number of live births and increasing number of terminations for neural tube defects.

Conclusion

Public health measures are warranted in order to replace termination of pregnancy with primary prevention in South-Eastern Hungary.     

Follicular fluid levels of anti-Müllerian hormone,insulin-like growth factor 1 and leptin in women with fertility disorders

Anti-Müllerian hormone (AMH), insulin-like growth factor 1 (IGF1) and leptin are produced in the granulosa cells of follicles and play an important role in the growth and maturation of follicles. The aim of our study was to monitor AMH, IGF1 and leptin levels in a group of healthy women and compare them to a group of women with fertility disorders. The second aim was the evaluation of biomarker levels in relation to the identified cause of infertility. Totally, 146 females were enrolled into our study. Seventy-two healthy controls and seventy-four females with fertility disorders were divided into four subgroups: anovulation, endometriosis, fallopian tube damage, unknown reason. IGF1 was the only biomarker with significantly lower levels throughout the entire group with fertility disorders. We did not identify any statistically significant differences for AMH and leptin. Regarding subgroups, significant differences were only observed in the group of anovulatory women. AMH and leptin showed higher levels while IGF1 showed lower levels. In conclusion, levels of AMH, IGF1 and leptin found in follicular fluid are sensitive markers for anovulatory fertility disorders. AMH, IGF1 and leptin levels in follicular fluid have no relation to the fertility disorders caused by endometriosis, fallopian tube damage or disorders with unknown etiology.

Abbreviations: AMH: anti-Müllerian hormone; IGF1: insulin-like growth factor 1; PCOS: polycystic ovary syndrome     

Oxidative stress-mediated cytotoxicity and metabolism of T-2 toxin and deoxynivalenol in animals and humans: an update

Trichothecenes are a large family of structurally related toxins mainly produced by Fusarium genus. Among the trichothecenes, T-2 toxin and deoxynivalenol (DON) cause the most concern due to their wide distribution and highly toxic nature. Trichothecenes are known for their inhibitory effect on eukaryotic protein synthesis, and oxidative stress is one of their most important underlying toxic mechanisms. They are able to generate free radicals, including reactive oxygen species, which induce lipid peroxidation leading to changes in membrane integrity, cellular redox signaling, and in the antioxidant status of the cells. The mitogen-activated protein kinases signaling pathway is induced by oxidative stress, which also induces caspase-mediated cellular apoptosis pathways. Several new metabolites and novel metabolic pathways of T-2 toxin have been discovered very recently. In human cell lines, HT-2 and neosolaniol (NEO) are the major metabolites of T-2 toxin. Hydroxylation on C-7 and C-9 are two novel metabolic pathways of T-2 toxin in rats. The metabolizing enzymes CYP3A22, CYP3A29, and CYP3A46 in pigs, as well as the enzymes CYP1A5 and CYP3A37 in chickens, are able to catalyze T-2 toxin and HT-2 toxin to form the C-3′–OH metabolites. Similarly to carboxylesterase, CYP3A29 possesses the hydrolytic ability in pigs to convert T-2 toxin to NEO. T-2 toxin is able to down- or upregulate cytochrome P-450 enzymes in different species. The metabolism of DON in humans is region-dependent. Free DON and DON-glucuronide are considered to be the biomarkers for humans. The masked mycotoxin DON-3-β-d-glucoside can be hydrolyzed to free DON in the body. This review will provide useful information on the progress of oxidative stress as well as on the metabolism and the metabolizing enzymes of T-2 toxin and DON. Moreover, the literature will throw light on the blind spots of metabolism and toxicological studies in trichothecenes that have to be explored in the future.     

Hepatitis B in the family

During a 3-year period (1992–1995), 239 index cases of hepatitis B virus (HBV) infection and 459 members of their households from the Osijek-Baranja county were examined. The aim of the study was to determine the spread of HBV infection in the families with a member verified as a virus carrier, and to identify the family members with the highest risk of infection according to kinship degrees. The retrospective and prospective methods were used in the study. The probable route of infection was assessed by the use of an epidemiologic questionnaire, and the serologic status of the study subjects concerning infection with HBV was determined by enzyme immunoassays (HBsAg, anti-HBs, anti-HBe and anti-HBc). The first member of a family identified as a virus carrier was considered an index case. HBV infection was demonstrated in 334 (47.85%) out of a total of 698 subjects. Only 21 (6.28%) of the 334 subjects with verified HBV infection developed the clinical picture of acute hepatitis B. The ratio of clinically manifest vs inapparent infection was 1:16. Serologic traces of infection were detected in 95 of the 459 family members of the index cases, yielding a mean rate of the infection among the virus carrier family members of 20.70%.     

Strukturaufklärung eines dritten Bisabololoxides aus Matricaria Chamomilla L. und massenspektrometrischer Vergleich der Bisabololoxide A,B und C

Structure of a Third Bisabololoxide from Matricaria Chamomilla L. During the isolation of the liquid (?)-α-bisabololoxides A and B (2 and 5) a small amount of a crystalline substance with m.p. 99–100° was separated and identified as a third (?)-α-bisabololoxide. The structure of this new bisabololoxide C was elucidated with NMR- and mass spectra and in combination with GLC-MS, further on the basis of chemical evidence. Using the same methods the (?)-α-bisabololoxides A and B have been again investigated and structures, 2 and 5 were confirmed.     

Radioiodination of mouse anti-III beta-tubulin antibodies and their evaluation with respect to their use as diagnostic agents for peripheral neuropathies.

The monoclonal antibody TU-20 and its scFv fragment were radiolabeled with 125 I in order to develop new imaging agents against the specific neuronal marker III beta-tubulin. The reaction via chloramine-T using thiosulfate as a stopping reductant was determined as the most convenient way for radioiodination. The preserved immunological properties of radioiodinated species were estimated by ELISA, electrophoresis, and immunohistochemistry with autoradiography. Biodistribution studies revealed a different behavior of radioiodinated TU-20 and its scFv.