Microdissection TESE is superior to conventional TESE in patients with nonobstructive azoospermia caused by Y chromosome microdeletions.

Nonobstructive azoospermia is caused in up to 10% by microdeletions of the Y chromosome in the azoospermia factor (AZF) region, which is divided into three nonoverlapping areas (AZFa, AZFb and AZFc). In 25 male patients with AZF microdeletions, the results of two different techniques for surgical sperm retrieval (SR), conventional multilocular TESE and microdissection TESE, were studied retrospectively over a period of 19 years. Conventional multilocular TESE was carried out in 11 patients and microdissection TESE in 14 patients. Successful SR was possible only in patients with isolated AZFc microdeletions, so only the 20 patients with AZFc microdeletions alone were taken into account for the comparison of the both operative techniques. The sperm detection rate for conventional multilocular TESE was 25%, the sperm detection for microdissection TESE was significantly higher with 67%. In all patients, a histological examination of the testicular tissue was carried out, which showed a mixed picture, but Sertoli-cell-only syndrome in most cases. FSH was no prognostic marker for successful SR. In two of six couples performing an intracytoplasmic sperm injection until now, a pregnancy occurred.

Cross-amplification and characterization of microsatellite loci in Acropora austera from the south-western Indian Ocean.

Here, we report the successful cross-species amplification of previously published acroporid microsatellite markers in the coral Acropora austera from the south-western Indian Ocean. This fast-growing species is a major reef-building coral on South African reefs; however, it is the most damaged coral by scuba diving activity, and is known to be very susceptible to coral bleaching. Neither genetic information nor symbiont-free host tissue was available to develop novel microsatellite markers for this species. Cross-species amplification of previously published microsatellite markers was considered as an alternative to overcome these problems. Of the 21 microsatellite markers tested, 6 were reliably amplified, scored, and found to contain polymorphic loci (3-15 alleles). Although microsatellite sequences are believed to be scarce in the Acropora genome because of its small size, the results of this study and previous research indicate that the microsatellite sequences are well conserved across Acropora species. A detailed screening process identified and quantified the sources of error and bias in the application of these markers (e.g., allele scoring error, failure rates, frequency of null alleles), and may be accounted for in the study of the contemporary gene flow of A. austera in the south-western Indian Ocean.

Protein folding causes an arrest of preprotein translocation into mitochondria in vivo.

With vital yeast cells, a hybrid protein consisting of the amino-terminal third of the precursor to cytochrome b2 and of the entire dihydrofolate reductase was arrested on the import pathway into mitochondria. Accumulation of the protein in the mitochondrial membranes was achieved by inducing a stable tertiary structure of the dihydrofolate reductase domain. Thereby, three salient features of mitochondrial protein uptake in vivo were demonstrated: its posttranslational character; the requirement for unfolding of precursors; and import through translocation contact sites. The permanent occupation of translocation sites by the fusion protein inhibited the import of other precursors; it did, however, not lead to leakage of mitochondrial ions, implying the existence of a channel that is sealed around the membrane spanning polypeptide segment.

The influence of culture conditions on the production of colony-stimulating activity by human placenta.

The growth of human granulopoietic progenitor cells (CFUc) in vitro is stimulated by supernatants of human placental tissue cultures. The placenta culture was the subject of systematic experiments with the aim of improving the concentration of colony-stimulating activity (CSA) in the crude material. Different culture parameters were varied and analyzed separately on the basis of dose-response studies. Maximum levels of CSA in human placental conditioned medium (HPCM) were obtained from 7-day cultures with a tissue-to-medium ratio of 1 to 20 and a depth of the culture fluid of 3 mm. Moreover, these modifications of the placenta culture resulted in a considerable reduction of inhibitors. HPCM stimulation of colony growth in agar unfailingly equaled feeder layer stimulation both in terms of colony number and size, each placenta producing enough material for maximum stimulation of 30,000 cultures.

Growth hormone radiologand assay unresponsive to human prolactin.

A specific and sensitive radioligand assay for growth hormone with female rat liver plasma membranes is presented. Growth hormones of different species are able to displace labelled human growth hormone from membrane binding sites with parallel standard curves. Human prolactin V-L-S is not equal to 1 and the international human prolactin standard MRC 71/222 do not affect the assay. Human prolactin preparations with different growth hormone content displace human growth hormone tracer only to the same extent as they contain growth hormone when measured by radioimmunoassay.

Bilosespens A and B: two novel cytotoxic sesterpenes from the marine sponge Dysidea cinerea.

[formula: see text] Two novel sesterpenes, bilosespens A and B (1 and 2) were isolated from the Red Sea sponge Dysidea cinerea collected in the Dahlak archipelago, Eritrea. The structure of the mixture of the two inseparable compounds was established by spectroscopic analysis, mainly by 1D and 2D NMR measurements. The mixture of bilosespens A and B is cytotoxic to a few human cancer cells.

Postpartum blues: relationship between not-protein bound steroid hormones in plasma and postpartum mood changes.

The relationship between non-bound steroid hormone levels in plasma and the occurrence of postpartum mood changes was investigated in 26 newly delivered mothers throughout the first 5 days postpartum. Studies with saliva samples had reported higher concentrations of 17 beta-estradiol and progesterone on the days of symptoms in women experiencing postpartum blues. As there had been a controversy as to how far saliva concentrations reflect free hormone levels in plasma, free hormone levels of 17 beta-estradiol and progesterone were determined in plasma using ultrafiltration. No significant difference concerning free hormone levels could be found between women with and without postpartum blues.

Haliclorensin, a Novel Diamino Alkaloid from the Marine Sponge Haliclonatulearensis

Haliclorensin (1), a novel diamino alkaloid possessing an azacyclodecane ring, has been isolated from the sponge Haliclona tulearensis. Its structure was elucidated on the basis of spectroscopic data, as well as by comparison with gamma-amino azacycloalkanes.

[Intracytoplasmic injection of epididymal and testicular sperm after failed heterologous insemination]. / Zur intrazytoplasmatischen Injektion von epididymalen und testikulären Spermien nach frustranen heterologen Inseminationen.

We report on our experiences with intracytoplasmic injection (ICSI) of epididymal and testicular spermatozoa (MESA, TESE) from azoospermic men whose wives had previously failed to become pregnant after several cycles of artificial insemination by donor (AID); because we do not perform AID treatment in our clinic, all these treatments were carried out in other fertility centers as well as the female diagnostic of sterility. In 3 husbands we could not find any testicular spermatozoa or spermatids, leaving 15 women under treatment. Of these 15 women, 9 became pregnant. This accounts for a pregnancy rate per patient of 60%. We believe that functional defects of the oocytes and somatizing psychological problems concerning AID are predominantly responsible for these results and that both problems can be overcome by ICSI. Besides, these results demonstrate that ICSI/MESA and ICSI/TESE are effective approaches in the treatment of azoospermic men and that using cryopreserved spermatozoa is not disadvantageous in the outcome of ICSI.

Reefs and islands of the Chagos Archipelago, Indian Ocean: why it is the world's largest no-take marine protected area.

The Chagos Archipelago was designated a no-take marine protected area (MPA) in 2010; it covers 550 000 km2, with more than 60 000 km2 shallow limestone platform and reefs. This has doubled the global cover of such MPAs.It contains 25-50% of the Indian Ocean reef area remaining in excellent condition, as well as the world's largest contiguous undamaged reef area. It has suffered from warming episodes, but after the most severe mortality event of 1998, coral cover was restored after 10 years.Coral reef fishes are orders of magnitude more abundant than in other Indian Ocean locations, regardless of whether the latter are fished or protected.Coral diseases are extremely low, and no invasive marine species are known.Genetically, Chagos marine species are part of the Western Indian Ocean, and Chagos serves as a 'stepping-stone' in the ocean.The no-take MPA extends to the 200 nm boundary, and. includes 86 unfished seamounts and 243 deep knolls as well as encompassing important pelagic species.On the larger islands, native plants, coconut crabs, bird and turtle colonies were largely destroyed in plantation times, but several smaller islands are in relatively undamaged state.There are now 10 'important bird areas', coconut crab density is high and numbers of green and hawksbill turtles are recovering.Diego Garcia atoll contains a military facility; this atoll contains one Ramsar site and several 'strict nature reserves'. Pollutant monitoring shows it to be the least polluted inhabited atoll in the world. Today, strict environmental regulations are enforced.Shoreline erosion is significant in many places. Its economic cost in the inhabited part of Diego Garcia is very high, but all islands are vulnerable.Chagos is ideally situated for several monitoring programmes, and use is increasingly being made of the archipelago for this purpose.

Transport of proteins into mitochondria: translocational intermediates spanning contact sites between outer and inner membranes.

Translocational intermediates of precursor proteins of ATPase F1 beta subunit and cytochrome c1 across mitochondrial membranes were analyzed using two different approaches, transport at low temperature and transport after binding of precursor proteins to antibodies. Under both conditions precursors were partially transported into mitochondria in an energy-dependent manner. They were processed by the metalloprotease in the matrix but a major proportion of the polypeptide chains was still present at the outer face of the outer mitochondrial membrane. We conclude that transfer of precursors into the inner membrane or matrix space occurs through "translocation contact sites"; precursor polypeptides to F1 beta and cytochrome c1 enter the matrix space with the amino terminus first; and a membrane potential is required for the transmembrane movement on an amino-terminal "domain-like" structure but not for completing translocation of the major part of the polypeptides.

Comparative analytical studies on recombinant and native human somatotropin.

In polyacrylamide gel electrophoresis and isoelectric focusing, somatotropin produced by recombinant DNA technology is as heterogeneous as highly purified native pituitary somatotropin. This heterogeneity is not attributable to different degrees of deamination of a single molecular species. In addition to the main protein of 22 kDa, the cloned products contain traces of interchain disulphide dimers of somatotropin. The quantitative amino acid analyses of the three cloned somatotropins investigated are neither identical nor do they correspond to the analysis of the native pituitary hormone. Moreover, there are discrepancies between the amino acid compositions of the hormones studied and the generally recognized amino acid analysis for human somatotropin.

Transport of ADP/ATP carrier into mitochondria. Precursor imported in vitro acquires functional properties of the mature protein.

Precursor to ADP/ATP carrier synthesized in vitro is transferred into isolated mitochondria to a protease-resistant location. This process requires an electrical potential across the inner membrane. We show now that precursor imported in a cell-free system exhibits the same resistance to protease as the mature endogenous carrier. Furthermore, transferred protein, but not receptor-associated precursor, binds carboxy-atractyloside, a specific inhibitor of the mature carrier and can be isolated by the purification procedure for the mature carrier. At least 70% of the precursor associated with mitochondria in the presence of a membrane potential acquires this functional characteristic. Finally, the binding of carboxyatractyloside can be modulated by treatment of the imported protein with sulfhydryl reagents in a manner indistinguishable from the authentic carrier protein. We conclude that import in vitro leads to correct assembly and orientation of the ADP/ATP carrier in the mitochondria.

Preparative purification of human placental colony-stimulating factors.

For preparative purification of colony-stimulating factors (CSF) from human placental conditioned medium, cation exchange chromatography, gel filtration, and isoelectric focusing were combined. The individual fractions were tested using the growth in agar of cryopreserved human bone marrow (dose-response curves). Furthermore, the active preparations were characterized by analytical isoelectric focusing. Two fractions with highly enriched biological activity were isolated. They have the isoelectric points 5.4 and 5.6, respectively. Their specific activity exceeds that of the crude material by a factor of 60. Like crude material, they induce predominantly granulocytic colonies. The biochemical heterogeneity of biological activity in placental supernatants is discussed.

Transfer of proteins into mitochondria. Precursor to the ADP/ATP carrier binds to receptor sites on isolated mitochondria.

The precursor form of Neurospora crassa mitochondrial ADP/ATP carrier synthesized in a cell-free protein-synthesizing system can be imported into isolated mitochondria. If the mitochondrial transmembrane potential is abolished, import does not occur but the precursor binds to the mitochondrial surface. Upon reestablishment of the membrane potential, the bound precursor is imported. This occurs without dissociation of the bound precursor from the mitochondrial surface. We conclude that the binding observed represents an interaction with receptor sites and thus is an early step in the import pathway.

Proteinaceous receptors for the import of mitochondrial precursor proteins.

Mild trypsin treatment of isolated Neurospora mitochondria strongly inhibits their ability to bind and import the precursors of several mitochondrial proteins. Evidence is presented for two proteins, the ADP/ATP carrier and the mitochondrial porin, that specific binding of the precursors to the outer surface of the mitochondria is affected by the protease treatment. We suggest that the receptors that mediate the import of these two precursors are proteinaceous. Treatment of mitochondria with elastase also inhibits the binding and import of the ADP/ATP carrier and the porin. In contrast the import of the precursors of subunits 2 and 9 of the mitochondrial proton-translocating ATPase was unaffected by elastase treatment at the concentrations used. We suggest that the import pathways of the latter two proteins are distinct from those of the ADP/ATP carrier and the porin.

Heterogeneity of porcine somatotropin.

A chromatographical method is presented by which highly purified porcine somatotropin can be separated preparatively into five subfractions. The rechromatographed subfractions show comparable biological activities and molecular sizes, but they differ characteristically in the polyacrylamide gel electrophoresis and in the isoelectric focusing. Relative small differences are found in the amino acid composition of these fractions. The question is discussed, whether the term multiple forms or isohormones of porcine somatotropin is suitable for the growth promoting fractions.

Nucleotide sequence and 3'-end deletion studies indicate that the K(+)-uptake protein kup from Escherichia coli is composed of a hydrophobic core linked to a large and partially essential hydrophilic C terminus.

The kup (formerly trkD) gene from Escherichia coli encodes a minor K(+)-uptake system. The gene is located just upstream of the rbsDACBK operon at 84.5 min on the chromosome and is transcribed clockwise. kup codes for a 69-kDa protein, which may be composed of two domains. The first 440 amino acid residues appear to form an integral membrane protein that might traverse the cell membrane 12 times. The C-terminal 182 amino acid residues are predicted to form a hydrophilic domain located at the cytoplasmic side of the membrane. Deletion studies from the 3' end of kup showed that removal of almost the complete hydrophilic domain of the protein reduced, but did not abolish, K(+)-uptake activity.

Clathculins A and B, two novel nitrogen-containing metabolites from the sponge Clathrina aff. reticulum.

Two novel acyclic diaza alkenynes, clathculins A and B (1 and 2), were isolated from the Indo-Pacific sponge Clathrina aff. reticulum collected in Sodwana Bay, South Africa. The structure of the mixture of the two unstable inseparable compounds was established by spectroscopic analysis, mainly 1D and 2D NMR measurements and two chemical transformations. Clathculins A and B are the first reported linear marine metabolites containing a 1,2-diaminoethane moiety.

Preparation and characteristics of porcine growth hormone.

A recently published method for preparation of porcine growth hormone resulted in a highly purified protein with good biological activity. However, after storing for some months the originally homogeneous hormone separated again into several fractions when rechromatographed on ion exchange columns. The biological activity, found in one of these fractions, was clearly diminished compared with the activity of a freshly prepared hormone. In the present paper a modified procedure is described for the isolation of a more stable porcine growth hormone. The influence of ions, involved in buffers of the same molarity and the same pH, upon ion exchange chromatography of porcine growth hormone is discussed. The purified hormone shows high biological activity in the tibia test and is free of activities of other pituitary hormones. The molecular weight is about 20 000; only phenylalanine is found as N-terminal as well as C-terminal amino acid; the amino acid composition resembles neither that of porcine growth hormone described in literature nor that of human growth hormone.