Decoupling of erosion and precipitation in the Himalayas

The hypothesis that abrupt spatial gradients in erosion can cause high strain rates in active orogens has been supported by numerical models that couple erosional processes with lithospheric deformation via gravitational feedbacks. Most such models invoke a 'stream-power' rule, in which either increased discharge or steeper channel slopes cause higher erosion rates. Spatial variations in precipitation and slopes are therefore predicted to correlate with gradients in both erosion rates and crustal strain. Here we combine observations from a meteorological network across the Greater Himalaya, Nepal, along with estimates of erosion rates at geologic timescales (greater than 100,000 yr) from low-temperature thermochronometry. Across a zone of about 20 km length spanning the Himalayan crest and encompassing a more than fivefold difference in monsoon precipitation, significant spatial variations in geologic erosion rates are not detectable. Decreased rainfall is not balanced by steeper channels. Instead, additional factors that influence river incision rates, such as channel width and sediment concentrations, must compensate for decreasing precipitation. Overall, spatially constant erosion is a response to uniform, upward tectonic transport of Greater Himalayan rock above a crustal ramp.

Abnormal methylation of imprinted genes in human sperm is associated with oligozoospermia

Genomic imprinting marks in the male germ line are already established in the adult germinal stem cell population. We studied the methylation patterns of H19 and MEST imprinted genes in sperm of control and oligozoospermic patients, by bisulphite genomic sequencing. We here report that 7 out of 15 (46.7%) patients with a sperm count below 10 x 10(6)/ml display defective methylation of H19 and/or MEST imprinted genes. In these cases, hypomethylation was observed in 5.54% (1.2-8.3%) and complete unmethylation in 2.95% (0-5.9%) of H19 clones. Similarly, for the CTCF-binding site 6, hypomethylation occurred in 4.8% (1.2-8.9%) and complete unmethylation in 3.7% (0-6.9%) of the clones. Conversely, hypermethylation occurred in 8.3% (3.8-12.2%) and complete methylation in 6.1% (3.8-7.6%) of MEST clones. Of the seven patients presenting imprinting errors, two had both H19 hypomethylation and MEST hypermethylation, whereas five displayed only one imprinted gene affected. The frequency of patients with MEST hypermethylation was highest in the severe oligozoospermia group (2/5 patients), whereas H19 hypomethylation was more frequent in the moderate oligozoospermia (2/5 patients). In all cases, global sperm genome methylation analysis (LINE1 transposon) suggested that defects were specific for imprinted genes. These findings could contribute to an explanation of the cause of Silver-Russell syndrome in children born with H19 hypomethylation after assisted reproductive technologies (ART). Additionally, unmethylation of the CTCF-binding site could lead to inactivation of the paternal IGF2 gene, and be linked to decreased embryo quality and birth weight, often associated with ART.

High frequency of DAZ1/DAZ2 gene deletions in patients with severe oligozoospermia

Deletions of the DAZ gene family in distal Yq11 are always associated with deletions of the azoospermia factor c (AZFc) region, which we now estimate extends to 4.94 Mb. Because more Y gene families are located in this chromosomal region, and are expressed like the DAZ gene family only in the male germ line, the testicular pathology associated with complete AZFc deletions cannot predict the functional contribution of the DAZ gene family to human spermatogenesis. We therefore established a DAZ gene copy specific deletion analysis based on the DAZ-BAC sequences in GenBank. It includes the deletion analysis of eight DAZ-DNA PCR markers [six DAZ-single nucleotide varients (SNVs) and two DAZ-sequence tag sites (STS)] selected from the 5' to the 3'end of each DAZ gene and a deletion analysis of the gene copy specific EcoRV and TaqI restriction fragments identified in the internal repetitive DAZ gene regions (DYS1 locus). With these diagnostic tools, 63 DNA samples from men with idiopathic oligozoospermia and 107 DNA samples from men with proven fertility were analysed for the presence of the complete DAZ gene locus, encompassing the four DAZ gene copies. In five oligozoospermic patients, we found a DAZ-SNV/STS and DYS1/EcoRV and TaqI fragment deletion pattern indicative for deletion of the DAZ1 and DAZ2 gene copies; one of these deletions could be identified as a 'de-novo' deletion because it was absent in the DAZ locus of the patient's father. The same DAZ deletions were not found in any of the 107 fertile control samples. We therefore conclude that the deletion of the DAZ1/DAZ2 gene doublet in five out of our 63 oligozoospermic patients (8%) is responsible for the patients' reduced sperm numbers. It is most likely caused by intrachromosomal recombination events between two long repetitive sequence blocks (AZFc-Rep1) flanking the DAZ gene structures.

High deletion frequency of the complete AZFa sequence in men with Sertoli-cell-only syndrome

We have developed a rapid screening protocol for deletion analysis of the complete AZFa sequence (i.e. 792 kb) on the Y chromosome of patients with idiopathic Sertoli-cell-only (SCO) syndrome. This Y deletion was mapped earlier in proximal Yq11 and first found in the Y chromosome of the SCO patient JOLAR, now designated as the AZFa reference patient. We now show that similar AZFa deletions occur with a frequency of 9% in the SCO patient group. In two multiplex polymerase chain reaction experiments, deletions of the complete AZFa sequence were identified by a typical deletion pattern of four new sequence-tagged sites (STS): AZFa-prox1, positive; AZFa-prox2, negative; AZFa-dist1, negative; AZFa-dist2, positive. The STS were established in the proximal and distal neighbourhoods of the two retroviral sequence blocks (HERV15yq1 and HERV15yq2) which encompass the break-point sites for AZFa deletions of the human Y chromosome. We have found deletions of the complete AZFa sequence always associated with a uniform SCO pattern on testicular biopsies. Patients with other testicular histologies as described in the literature and in this paper have only partial AZFa deletions. The current AZFa screening protocols can therefore be improved by analysing the extension of AZFa deletions. This may provide a valuable prognostic tool for infertility clinics performing testicular sperm extraction, as it would enable the exclusion of AZFa patients with a complete SCO syndrome.

Headspace solid phase microextraction (SPME) analysis of flavor compounds in wines. Effect of the matrix volatile composition in the relative response factors in a wine model

The application of headspace solid phase microextraction (SPME) for flavor analysis has been studied. Headspace SPME sampling was tested for nine common wine flavor compounds in 10% (v/v) aqueous ethanol: linalool, nerol, geraniol, 3-methyl-1-butanol, hexanol, 2-phenylethanol, ethyl hexanoate, ethyl octanoate, and ethyl decanoate. The chemical groups (monoterpenoids, aliphatic and aromatic alcohols, and esters) showed specific behavior in SPME analysis. SPME sampling parameters were optimized for these components. Relative response factors (RRFs), which establish the relationship between the concentration of the compound in the matrix liquid solution and the GC peak area, were estimated for all compounds. Log(10)(RRF) varied from 0 (3-methyl-1-butanol) to 3 (ethyl decanoate), according to their molecular weight. Quantification by SPME was shown to be highly dependent on the matrix composition; the compounds with higher RRF were the less affected. As a consequence, the data obtained with this methodology should be used taking into consideration these limitations, as shown in the analysis of four monovarietal Bairrada white wines (Arinto, Bical, Cerceal, and Maria Gomes).

Predictive value of testicular histology in secretory azoospermic subgroups and clinical outcome after microinjection of fresh and frozen-thawed sperm and spermatids

BACKGROUND

A retrospective study was carried out on 159 treatment cycles in 148 secretory azoospermic patients to determine whether histopathological secretory azoospermic subgroups were predictive for gamete retrieval, and to evaluate outcome of microinjection using fresh or frozen-thawed testicular sperm and spermatids.

METHODS

Sperm and spermatids were recovered by open testicular biopsy and microinjected into oocytes. Fertilization and pregnancy rates were assessed.

RESULTS

In hypoplasia, 97.7% of the 44 patients had late spermatids/sperm recovered. In maturation-arrest (MA; 47 patients), 31.9% had complete MA, and 68.1% incomplete MA due to a focus of early (36.2%) or late (31.9%) spermiogenesis. Gamete retrieval was achieved in 53.3, 41.2 and 93.3% of the cases respectively. In Sertoli cell-only syndrome (SCOS; 57 patients), 61.4% were complete SCOS, whereas incomplete SCOS cases showed one focus of MA (5.3%), or of early (29.8%) and late (3.5%) spermiogenesis. Only 29.8% of the patients had a successful gamete retrieval, 2.9% in complete and 77.3% in incomplete SCOS cases. In total, there were 87 ICSI, 39 elongated spermatid injection (ELSI) and 33 round spermatid injection (ROSI) treatment cycles, with mean values of fertilization rate of 71.4, 53.6 and 17%, and clinical pregnancy rates of 31.7, 26.3 and 0% respectively.

CONCLUSIONS

Histopathological subgroups were positively correlated with successful gamete retrieval. No major outcome differences were observed between testicular sperm and elongated spermatids, either fresh or frozen-thawed. However, injection of intact round-spermatids showed very low rates of fertilization and no pregnancies.

Influence of 5α-dihydrotestosterone and 17β-estradiol on human Sertoli cells metabolism

Sertoli cells metabolize glucose, converting it to lactate that is used by developing germ cells for their energy metabolism. Androgens and oestrogens have metabolic roles that reach far beyond reproductive processes. So, the main purpose of this study was to examine the effect of sex steroid hormones on metabolite secretion/consumption in human Sertoli cells. Human Sertoli cell-enriched primary cultures were maintained in a defined medium for 50 h and glucose, pyruvate, lactate and alanine variations were determined using (1) H-NMR spectra analysis, in the absence or presence of 100 nm 17β-estradiol (E(2) ) or 100 nm 5α-dihydrotestosterone (DHT). The mRNA expression levels of glucose transporters, lactate dehydrogenase and monocarboxylate transporters were also determined using semi-quantitative RT-PCR. Cells cultured in the absence (control) or presence of E(2) consumed the same amounts of glucose at similar rates during the 50 h. During the first 15 h of treatment with DHT, glucose consumption and glucose consumption rate were significantly higher. Nevertheless, DHT-treated cells secreted a significantly lower amount of lactate than control and E(2) -treated cells. Such a decrease was concomitant with a significant decrease in lactate dehydrogenase A mRNA levels after 50 h treatment in DHT-treated groups. Finally, alanine production was significantly increased in E(2) -treated cells after 25 h treatment, which indicated a lower redox/higher oxidative state for the cells on those conditions. These results support the existence of a relationship between sex steroid hormones action and energy metabolism, providing the first assessment of androgens and oestrogens as metabolic modulators of human Sertoli cells.

In-vitro maturation of round spermatids using co-culture on Vero cells

In an attempt to determine whether co-culture could promote sperm maturation, three patients with non-obstructive azoospermia, two with maturation arrest at the level of primary spermatocytes and one patient with <1% tubules showing complete spermatogenesis, and one patient with total globozoospermia, gave consent to experimentally co-culture round spermatids retrieved from the testicle on Vero cell monolayers. In all azoospermic patients elongating spermatids could be obtained from round spermatids. In one case of maturation arrest, of 37 round spermatids co-cultured for up to 5 days, 30% developed flagella, 46% matured to elongating and 19% to elongated spermatids, with one mature spermatozoon also obtained (3%). In the same patient, primary cultures of three round spermatids with flagella enabled development of one further mature spermatozoon. In the case with total globozoospermia, of six round spermatids co-cultured for up to 5 days, one mature spermatozoon was obtained, with a flagellum and normal head morphology. These preliminary findings suggest that it may be possible to overcome the round spermatid block, and even the triggering of morphological abnormalities arising at the spermiogenic level, by in-vitro maturation under special environmental conditions.

Developmental potential of elongating and elongated spermatids obtained after in-vitro maturation of isolated round spermatids

BACKGROUND

Round spermatid injections are associated with disappointing clinical outcomes, and although these cells have been shown to mature into late spermatids in vitro, the developmental potential of such gametes remains to be demonstrated.

METHODS

Round spermatids were isolated from 12 testicle samples of patients with obstructive azoospermia, hypoplasia, complete maturation arrest, and incomplete Sertoli cell-only syndrome. They were cultured for 7 days at 32 degrees C, 5% CO(2)in air, in microdrops of Vero cell-conditioned medium containing 10% synthetic serum substitute.

RESULTS

From the 238 round spermatids cultured, 25.2% attained the elongating and 5.5% the elongated spermatid stage (3-4 days per step). Relatively higher maturation rates were found in cases with obstructive azoospermia, but differences were significant only for elongated spermatids (9.3%). No differences were found in maturation rates between cases with non-obstructive azoospermia (4.3% of elongated spermatids). Experimental microinjections with elongating and elongated spermatids revealed a low fertilization rate (40.9%) but a normal blastocyst formation rate (60%).

CONCLUSIONS

Late spermatids resulting from in-vitro culture of round spermatids in conditioned medium, either in controls in cases with a spermiogenetic block, appeared able to successfully fertilize the human oocyte and elicit normal embryo development.

Calcium responses of human oocytes after intracytoplasmic injection of leukocytes, spermatocytes and round spermatids

Oocyte activation in mammals involves the action of a soluble sperm factor (SSF) that enables oocytes to develop a characteristic series of Ca2+ spikes (Ca2+ oscillations). SSF is also likely to be responsible for the Ca2+ oscillations driving oocyte activation after intracytoplasmic sperm injection [ICSI]. With an appropriate injection technique, Ca2+ oscillations do not develop spontaneously after ICSI but can be triggered by subsequent treatment of sperm-injected oocytes with Ca2+ ionophore. Here we show that Ca2+ oscillations, quite similar to those developing after ICSI, can be triggered by the ionophore treatment in human oocytes previously injected with human round spermatids. In contrast, oocytes injected with earlier spermatogenic cell (primary and secondary spermatocytes) and with non-germ cells (polymorphonuclear leukocytes) did not develop Ca2+ oscillations after the ionophore challenge although the subsequent injection of SSF did induce typical Ca2+ oscillations in these oocytes. Disintegration of the plasma membrane of the injected cells was detected in all cases by transmission electron microscopy. Thus, the absence of the typical oscillatory Ca2+ response in spermatocyte-injected oocytes was due to the actual deficiency of SSF in the spermatocytes rather than to a defective responsiveness of the injected oocytes or to the failure of SSF release into the oocyte cytoplasm. The ability of human round spermatids to induce a response to calcium in oocytes that is similar to that induced by mature spermatozoa may be important for normal embryonic development after spermatid conception.

Developmental changes in calcium content of ultrastructurally distinct subcellular compartments of preimplantation human embryos

The ultrastructural localization of mobilizable Ca2+ in different subcellular compartments of human oocytes and preimplantation embryos was studied using the potassium-pyroantimonate technique and transmission electron microscopy; the specificity was confirmed by chelation experiments and X-ray microanalysis. In unfertilized oocytes, Ca2+ was detected in small vesicles beneath the plasma membrane as well as in other forms of smooth endoplasmic reticulum (SER) and in mitochondria but not in cortical granules. In pronuclear zygotes and blastomeres of cleaving embryos, Ca(2+)-rich vesicles were no longer present close to the plasma membrane, and the entire periphery was poor in Ca(2+)-containing organelles which, however, were abundant in the perinuclear region. The uneven Ca2+ loading of SER and mitochondria from the pronuclear stage onwards suggests that Ca2+ release from both these types of organelle contributes to the embryonic Ca2+ signals. During mitosis, less Ca2+ was detected with organelles, but the antimonate reaction product was more abundant in the cytosol. These data suggest that, in addition to different forms of SER, mitochondria also act as a source of mobilizable Ca2+ in preimplantation human embryos. The previously described developmental and cell cycle related changes in the characteristics of Ca2+ signals are associated with the redistribution and structural reorganization of these organelles.

Intracellular pH regulation in human Sertoli cells: role of membrane transporters

Sertoli cells are responsible for regulating a wide range of processes that lead to the differentiation of male germ cells into spermatozoa. Intracellular pH (pHi) is an important parameter in cell physiology regulating namely cell metabolism and differentiation. However, pHi regulation mechanisms in Sertoli cells have not yet been systematically elucidated. In this work, pHi was determined in primary cultures of human Sertoli cells. Sertoli cells were exposed to weak acids, which caused a rapid acidification of the intracellular milieu. pHi then recovered by a mechanism that was shown to be particularly sensitive to the presence of the inhibitor DIDS (4,4′-diisothiocyanostilbene disulfonic acid). In the presence of amiloride and PSA (picrylsulfonic acid), pHi recovery was also significantly affected. These results indicate that, in the experimental conditions used, pHi is regulated by the action of an Na+-driven HCO3−/Cl−exchanger and an Na+/HCO3−co-transporter and also by the action of the Na+/H+exchanger. On the other hand, pHi recovery was only slightly affected by concanamycin A, suggesting that V-Type ATPases do not have a relevant action on pHi regulation in human Sertoli cells, and was independent of the presence of bumetanide, suggesting that the inhibition of the Na+/K+/Cl−co-transporter does not affect pHi recovery, not even indirectly via the shift of ionic gradients. Finally, pHi was shown to be sensitive to the removal of external Cl−, but not of Na+or K+, evidencing the presence of a membrane Cl−-dependent base extruder, namely the Na+-independent HCO3−/Cl−exchanger, and its role on pHi maintenance on these cells.

Tetracycline Antibiotics Induce Host-Dependent Disease Tolerance to Infection

Several classes of antibiotics have long been known to have beneficial effects that cannot be explained strictly on the basis of their capacity to control the infectious agent. Here, we report that tetracycline antibiotics, which target the mitoribosome, protected against sepsis without affecting the pathogen load. Mechanistically, we found that mitochondrial inhibition of protein synthesis perturbed the electron transport chain (ETC) decreasing tissue damage in the lung and increasing fatty acid oxidation and glucocorticoid sensitivity in the liver. Using a liver-specific partial and acute deletion of Crif1, a critical mitoribosomal component for protein synthesis, we found that mice were protected against sepsis, an observation that was phenocopied by the transient inhibition of complex I of the ETC by phenformin. Together, we demonstrate that mitoribosome-targeting antibiotics are beneficial beyond their antibacterial activity and that mitochondrial protein synthesis inhibition leading to ETC perturbation is a mechanism for the induction of disease tolerance.

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Doxycycline protects from sepsis beyond its direct antibacterial activity

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Doxycycline protection from infection is microbiome-independent

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Inhibition of mitochondrial protein synthesis induces disease tolerance

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Mild and transient perturbations of the mitochondrial ETC induce disease tolerance

Heterotrophy as a tool to overcome the long and costly autotrophic scale-up process for large scale production of microalgae

Industrial scale-up of microalgal cultures is often a protracted step prone to culture collapse and the occurrence of unwanted contaminants. To solve this problem, a two-stage scale-up process was developed – heterotrophically Chlorella vulgaris cells grown in fermenters (1^st stage) were used to directly inoculate an outdoor industrial autotrophic microalgal production unit (2^nd stage). A preliminary pilot-scale trial revealed that C. vulgaris cells grown heterotrophically adapted readily to outdoor autotrophic growth conditions (1-m³ photobioreactors) without any measurable difference as compared to conventional autotrophic inocula. Biomass concentration of 174.5 g L⁻¹, the highest value ever reported for this microalga, was achieved in a 5-L fermenter during scale-up using the heterotrophic route. Inocula grown in 0.2- and 5-m³ industrial fermenters with mean productivity of 27.54 ± 5.07 and 31.86 ± 2.87 g L⁻¹ d⁻¹, respectively, were later used to seed several outdoor 100-m³ tubular photobioreactors. Overall, all photobioreactor cultures seeded from the heterotrophic route reached standard protein and chlorophyll contents of 52.18 ± 1.30% of DW and 23.98 ± 1.57 mg g⁻¹ DW, respectively. In addition to providing reproducible, high-quality inocula, this two-stage approach led to a 5-fold and 12-fold decrease in scale-up time and occupancy area used for industrial scale-up, respectively.

CXCL5-mediated recruitment of neutrophils into the peritoneal cavity of Gdf15-deficient mice protects against abdominal sepsis

Sepsis is a life-threatening organ dysfunction condition caused by a dysregulated host response to an infection. Here we report that the circulating levels of growth and differentiation factor-15 (GDF15) are strongly increased in septic shock patients and correlate with mortality. In mice, we find that peptidoglycan is a potent ligand that signals through the TLR2-Myd88 axis for the secretion of GDF15, and that Gdf15-deficient mice are protected against abdominal sepsis due to increased chemokine CXC ligand 5 (CXCL5)-mediated recruitment of neutrophils into the peritoneum, leading to better local bacterial control. Our results identify GDF15 as a potential target to improve sepsis treatment. Its inhibition should increase neutrophil recruitment to the site of infection and consequently lead to better pathogen control and clearance.

Experimental vitrification of human compacted morulae and early blastocysts using fine diameter plastic micropipettes

BACKGROUND

Vitrification of human blastocysts has been successfully applied using grids, straws and cryoloops. We assessed the survival rate of human compacted morulae and early blastocysts vitrified in pipette tips with a smaller inner diameter and solution volume than the previously described open pulled straw (OPS) method.

METHODS

Excess day 5 human embryos (n = 63) were experimentally vitrified in vessels. Embryos were incubated at 37 degrees C with sperm preparation medium (SPM) for 1 min, SPM + 7.5% ethylene glycol (EG)/dimethylsulphoxide (DMSO) for 3 min, and SPM + 16.5% EG + 16.5% DMSO + 0.67 mol/l sucrose for 25 s. They were then aspirated (0.5 microl) into a plastic micropipette tip (0.36 mm inner diameter), exposed to liquid nitrogen (LN(2)) vapour for 2 min before being placed into a pre-cooled cryotube, which was then closed and plunged into LN(2). Embryos were warmed and diluted using 0.33 mol/l and 0.2 mol/l sucrose.

RESULTS

The survival rate for compacted morulae was 73% (22/30) and 82% (27/33) for early blastocysts.

CONCLUSIONS

The survival rates of human compacted morulae and early blastocysts after vitrification with this simple technique are similar to those reported in the literature achieved by slow cooling and other vitrification protocols.

Trem-2 Promotes Emergence of Restorative Macrophages and Endothelial Cells During Recovery From Hepatic Tissue Damage

Macrophages are pivotal in mounting liver inflammatory and tissue repair responses upon hepatic injury, showing remarkable functional plasticity. The molecular mechanisms determining macrophage transition from inflammatory to restorative phenotypes in the damaged liver remain unclear. Using mouse models of acute (APAP) and chronic (CCl4) drug-induced hepatotoxic injury we show that the immune receptor Trem-2 controls phenotypic shifts of liver macrophages and impacts endothelial cell differentiation during tissue recovery. Trem-2 gene ablation led to a delayed re-population of Kupffer cells correlating with deterred resolution of hepatic damage following acute and chronic injury. During tissue recovery, we found that macrophages transitioning to Kupffer cells expressed high levels of Trem-2. Acquisition of the transition phenotype was associated with a unique transcriptomic profile denoting strong responsiveness to oxidative stress and downmodulation of the pro-inflammatory phenotype, which was not observed in absence of Trem-2. During tissue recovery, lack of Trem-2 favored accumulation of a liver-damage associated endothelial cell population (LDECs), whose transcriptional program was compatible with endothelial de-differentiation. Accordingly, LDECs precursor potential is supported by the downregulation of surface endothelial cell markers and by striking in vitro morphological changes towards typical endothelial cells. In conclusion, we found that the dynamics of liver macrophages in response to liver injury are critically controlled by Trem-2 and this regulation is interlinked with the de-differentiation of endothelial cells and heightened liver pathology. We propose that Trem-2 promotes the transition from pro-inflammatory to tissue repair phase by driving the acquisition of restorative properties in phagocytic macrophages.

Ghrelin acts as energy status sensor of male reproduction by modulating Sertoli cells glycolytic metabolism and mitochondrial bioenergetics

Ghrelin is a growth hormone-releasing peptide that has been suggested to interfere with spermatogenesis, though the underling mechanisms remain unknown. We studied the effect of ghrelin in human Sertoli cells (hSCs) metabolic phenotype. For that, hSCs were exposed to increasing concentrations of ghrelin (20, 100 and 500 pM) mimicking the levels reported in obese, normal weight, and severely undernourished individuals. The metabolite production/consumption was determined. The protein levels of key glycolysis-related transporters and enzymes were assessed. The lactate dehydrogenase (LDH) activity was measured. Mitochondrial complexes protein levels and mitochondria membrane potential were also measured. We showed that hSCs express the growth hormone secretagogue receptor. At the concentration present in the plasma of normal weight men, ghrelin caused a decrease of glucose consumption and mitochondrial membrane potential in hSCs, though LDH activity and lactate production remained unchanged, illustrating an alteration of glycolytic flux efficiency. Exposure of hSCs to levels of ghrelin found in the plasma of severely undernourished individuals decreased pyruvate consumption and mitochondrial complex III protein expression. All concentrations of ghrelin decreased alanine and acetate production by hSCs. Notably, the effects of ghrelin levels found in severely undernourished individuals were more pronounced in hSCs metabolic phenotype highlighting the importance of a proper eating behavior to maintain male reproductive potential. In conclusion, ghrelin acts as an energy status sensor for hSCs in a dose-dependent manner, showing an inverse association with the production of lactate, thus controlling the nutritional support of spermatogenesis.

Clinical efficacy of spermatid conception: analysis using a new spermatid classification scheme

Fertilization and pregnancy outcomes of 50 round spermatid injection (ROSI) and 20 elongated spermatid injection (ELSI) treatment cycles are related to various characteristics of the cycles, with particular reference to spermatid developmental stage as assessed by using a classification scheme adapted to this purpose. Although this classification includes eight stages, a complete block was mostly detected at the earliest stage (Sa1) or at the latest stages (Sd1 and Sd2). Thus, spermiogenesis was blocked at Sa1 stage in 50 cases (71%), at Sd1 stage in eight cases (11%) and at Sd2 stage in 10 cases (14%). Only in two cases (3%) was spermiogenesis blocked at an intermediate stage (Sb2). Globally, fertilization rates were higher for ELSI than for ROSI. No pregnancy was achieved in the ROSI cycles, whereas nine pregnancies resulted from the ELSI cycles. Two of them (both with Sd2 spermatids) ended in a first trimester spontaneous abortion. Of the seven ongoing pregnancies, five are singleton (two with Sd1 spermatids, two with Sd2 spermatids, and one after a mixed transfer after injection of Sa2 and Sd1 spermatids) and two are twin (one with Sd1 and the other with Sd2 spermatids). No pregnancy was achieved in the two cycles with Sb2 spermatids. One of the two twin pregnancies has already resulted in the birth of two healthy children.

AZF and DAZ gene copy-specific deletion analysis in maturation arrest and Sertoli cell-only syndrome

Deletions of the AZFc region in Yq11.2, which include the DAZ gene family, are responsible for most cases of male infertility and were associated with severe oligozoospermia and also with a variable testicular pathology. To uncover the functional contribution of DAZ to human spermatogenesis, a DAZ gene copy-specific deletion analysis was previously established and showed that DAZ1/DAZ2 deletions associate with oligozoospermia. In this study we applied the same screening method to 50 control fertile males and 91 non-obstructive azoospermic males, 39 with Sertoli cell-only syndrome (SCOS) and 52 with meiotic arrest (MA). Samples were also screened with 24 sequence-tagged sites to the different AZF regions, including 114 control fertile males. After biopsy (testicular sperm extraction, TESE), residual spermiogenesis was found in 57.7% MA and 30.8% SCOS cases (incomplete syndromes). DAZ1/DAZ2 deletions were associated with the testicular phenotype of residual spermiogenesis as they were only found in two patients (8%) with incomplete MA. Differences between incomplete (23.3%) and complete (4.5%) MA cases regarding AZFc and DAZ1/DAZ2 deletion frequencies, and between incomplete (58.3%) and complete (11.1%) SCOS cases for AZFc deletions, suggest that incomplete syndromes might represent an aggravation of the oligozoospermic phenotype. As successful TESE was achieved in 87.5% of MA cases with AZFc and DAZ1/DAZ2 deletions and in 58.3% of SCOS cases with AZFc deletions, the present results also suggest that these molecular markers might be used for the establishment of a prognosis before TESE.

Developmental changes in calcium dynamics, protein kinase C distribution and endoplasmic reticulum organization in human preimplantation embryos

Developmental changes in the Ca2+ dynamics of human zygotes and preimplantation embryos were related to changes in the distribution of endoplasmic reticulum (ER) and protein kinase C (PKC). The fertilization-induced Ca2+ oscillations were typically observed over > 5 h, were ryanodine-sensitive and showed a periphery-to-centre propagation of Ca2+ waves. At the same time, ER and PKC were accumulated in the cell periphery. After the appearance of pronuclei, ryanodine-sensitive Ca2+ oscillations of lower amplitude and frequency were observed until the pronuclear breakdown. However, Ca2+ waves then began in the perinuclear region, in the area of ER and PKC accumulation and spread towards the cell periphery. During the second to fourth cell cycle, small sinusoidal Ca2+ fluctuations were observed; sparse higher-amplitude Ca2+ spikes, superimposed on these basal fluctuations, appeared shortly before cell division. The sinusoidal Ca2+ fluctuations were asynchronous in individual blastomeres and disappeared progressively in arrested embryos. The direction of Ca2+ wave propagation and the distribution of ER and PKC were similar to the situation observed in pronuclear zygotes. In contrast to the zygotes, ryanodine did not arrest the Ca2+ oscillations but augmented their amplitude and frequency. These data suggest that human pre-embryos use different mechanisms of Ca2+ signalling in the early post-fertilization period, during the pronuclear development and during cleavage.

Regucalcin is broadly expressed in male reproductive tissues and is a new androgen-target gene in mammalian testis

Regucalcin (RGN) is a calcium (Ca2+)-binding protein which regulates intracellular Ca2+homeostasis by modulating the activity of enzymes regulating Ca2+concentration and enhancing Ca2+-pumping activity. Several studies have described the pivotal role of proper Ca2+homeostasis regulation to spermatogenesis and male fertility. Recently,RGNwas identified as a sex steroid-regulated gene in prostate and breast; however, a possible role of RGN in spermatogenesis has not been examined. In this study, the expression and localization of RGN in rat and human testis, and other rat reproductive tissues was analyzed. Moreover, we studied whether RGN protein was present in seminiferous tubule fluid (STF). Finally, we examined the effect of 5α-dihydrotestosterone (DHT) on the expression ofRgnmRNA in rat seminiferous tubules (SeT) culturedex vivo. The results presented in this study show that RGN is expressed in Leydig and Sertoli cells, as well as in all types of germ cells of both rat and human testis. RGN is also expressed in rat prostate, epididymis, and seminal vesicles. Moreover, RGN protein is present in rat STF. The results also demonstrate thatRgnexpression is age dependent in rat testis, and is upregulated by the non-aromatizable androgen DHT in rat SeT culturedex vivo. Taken together, these findings indicate thatRgnis a novel androgen-target gene in rat testis and that it may have a role in male reproductive function, particularly in the control of spermatogenesis.

Aroma potential of two bairrada white grape varieties: Maria Gomes and Bical

Maria Gomes and Bical are the main white grape varieties in Portuguese Bairrada Appellation, which represent 80% and 15%, respectively, of white vineyard. To estimate their aroma potentialities, free and potential volatile components from the musts were examined. The free volatile components were extracted using a liquid-liquid continuous method and were analyzed by gas chromatography-mass spectrometry. The potential volatile compounds were determined after elimination of the free components by heat and enzymatic treatments. Principal component analysis was used to establish relations between the compounds and the varieties and also the form (free or in potential). Maria Gomes has 11.5 mg/L volatile compounds, of which 33% are in free form; Bical has 4.4 mg/L volatile compounds, of which 46% are in free form. A total of 59 compounds was identified and quantified. In Maria Gomes, the sum of the terpenoids is within the perception limits for hotrienol (0.21 mg/L) and linalool (0.20 mg/L). In Bical, benzyl alcohol and phenylethylethanol represent 20% of the volatile compounds. Considering that the volatile composition pattern of Maria Gomes and Bical varieties are different, wine-making technologies should be developed specifically for each variety.

Correlation between myocardial fibrosis and the occurrence of atrial fibrillation in hypertrophic cardiomyopathy: a cardiac magnetic resonance imaging study

Cardiac magnetic resonance imaging (CMR) in hypertrophic cardiomyopathy (HCM) often shows delayed contrast enhancement (DE) representing regions of focal myocardial fibrosis. Atrial fibrillation (AF) is a commonly reported complication of HCM. We determined the relationship between the presence of left ventricular myocardial fibrosis (LVMF) detected by DE-CMR and the occurrence AF in a series of patients with HCM. 67 patients with HCM (47 males; mean age 50.1+/-18.5 years) were studied by CMR measuring mass of LVMF, left ventricular mass, volume and function, and left atrial (LA) area. AF was present in 17 (25%) patients. LVMF was observed in 57% of patients. AF was significantly more frequent in patients who also showed LVMF, compared with the group without LVMF (42.1% vs. 3.4%, respectively; p<0.0001). LA size was larger in patients showing DE (LA area: 37.4+/-11.1 vs. 25.9+/-6.8 cm(2); respectively, p=0.0001). AF in HCM is related with myocardial fibrosis detected by DE-CMR and dilatation of the LA. This fact adds to the proven adverse prognostic value of myocardial fibrosis in HCM, thus, reinforcing the usefulness of this technique in the assessment of these patients.

Preimplantation genetic diagnosis for familial amyloidotic polyneuropathy (FAP)

Preimplantation genetic diagnosis (PGD) was developed more than a decade ago to offer an alternative to prenatal diagnosis for couples at risk of transmitting an inherited disease to their offspring. Portuguese-type familial amyloidotic polyneuropathy (FAP type I), is an autosomal dominant disease presenting an inherited mutation in the gene encoding the plasma protein transthyretin (TTR). We here report the first protocol for single-cell detection of the Met30 mutation in FAP type I and its application to PGD. A nested PCR reaction for exon 2 of the TTR gene was developed. The PCR product was then analysed by restriction enzyme analysis and SSCP allowing the detection of the point mutation. Ten clinical cycles were performed in seven couples. From the 93 metaphase II (MII) injected oocytes, 82 were normally fertilized and 78 were biopsied. A positive signal in the nested PCR reaction was obtained in 61 blastomeres, corresponding to a DNA amplification efficiency of 78.2%. No allele dropout (ADO) or contamination were detected. A biochemical pregnancy was obtained in three cases and a clinical pregnancy in one couple is actually in normal evolution.