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Summary: Reduced or no progressive sperm motility in the fresh ejaculate defines asthenozoospermia as one of the major causes of male infertility. The axonemal heavy chain dynein type 11 (DNAH11) gene encodes for one of the axonemal dynein heavy chain (DHC) family members and participates in assembling respiratory cilia and sperm flagella. Given the high degree of conservation of DNAH11, mutations could give rise to primary ciliary dyskinesia (PCD) and asthenozoospermia. To date, few studies have reported on the association between variants in DNAH11 and asthenozoospermia. In the present study, 87 patients with idiopathic asthenozoospermia for variants in DNAH11 were screened by using high-throughput targeted gene sequencing technology. Bioinformatics analysis was further assessed. We found compound heterozygous variants (c.9484-1 G>T, c.12428 T>C) of DNAH11 detected in 1 of 87 patients. The variant c.9484-1 G>T was confirmed as a novel virulence variant which was predicted to affect splicing by Human Splicing Finder 3.1. And c.12428 T>C was predicted to be mildly pathogenic in silico analysis. We found that DNAH11 polymorphisms display strong associations with asthenozoospermia, and may contribute to an increased risk of male infertility in Chinese patients. [ABSTRACT FROM AUTHOR]

Immobilized sulfate-reducing bacteria (SRB) in polyvinyl alcohol (PVA)-sodium alginate matrix were applied as biosorbents to remove cadmium (Cd) from aqueous solutions. Multiple characterization techniques including scanning electron microscope (SEM)-energy dispersive spectrometer (EDS), and Fourier transform infrared (FT-IR) spectra indicate that immobilized beads provided a suitable microenvironment for SRB. Performance tests show that Cd removal was highly affected by pH value and temperature, with optimum temperature at 35ºC and pH value of 8.0. A pseudo second-order model was applied to describe the adsorption kinetic. FT-IR and x-ray photoelectron spectroscopy (XPS) analyses imply that biosorption, sulfide, and hydroxide precipitation are the main mechanisms for removing Cd. The immobilized SRB beads have great potential for remediating Cd-containing wastewater. [ABSTRACT FROM AUTHOR]

Background/aim: This study aimed to explore the breakpoints in chromosome 3 translocation and the clinical features present in male carriers to enable informed genetic counseling of these patients. Materials and methods: A total of 5235 men who were infertile or receiving counseling for infertility were recruited. Cytogenetic analyses were performed using G-banding. A search for translocations on chromosome 3 involved in male infertility was performed using PubMed, Google Scholar, and CNKI. The relationships of translocation breakpoints with male infertility and recurrent pregnancy loss were also analyzed. Results: Among the 82 patients with balanced reciprocal translocations among 5235 male patients, 12 patients were carriers of chromosome 3 translocation: two presented with pregestational infertility, while 10 presented with gestational infertility. The breakpoint at 3p13 was related to pregestational infertility, whereas those at 3p23, 3q10, 3q12, 3q21, 3q25, and 3q29 were related to gestational infertility. By an analysis combining data from the literature, 63 carriers of chromosome 3 translocation were reviewed and all breakpoints at chromosome 3 were correlated with gestational infertility. Conclusion: All breakpoints at chromosome 3 were correlated with gestational infertility. The breakpoints at 3q12 and 3q29 were the most common. Carriers of chromosome 3 translocation should thus be counseled on the need for other chromosomal breakpoints and preimplantation genetic diagnosis or prenatal testing. [ABSTRACT FROM AUTHOR]

As scattered elements, thallium (Tl) contamination poses a significant threat to human health due its high toxicity. Sulfate-reducing bacteria (SRB) embedded in PVA-sodium alginate matrix was utilized as a novel bio-remover to remove Tl from aqueous solution. The effect of pH, temperature, and initial Tl concentration on removal capacity of immobilized beads were studied and discussed in this work. The optimum bio-removal conditions were at pH value of 6, temperature of 35°C, and initial Tl concentration of 50 mg.L-1. The pseudo second-order model for Tl adsorption was applicable to all the removal data over the entire time range and intralayer diffusion was not the only rate-determining step. The bio-removal data conformed well to Langmuir isotherm model. Fourier transform infrared spectroscopy showed that sulfate reduction played an important role in Tl removal. The groups of carboxylate radical might be involved in sulfate reduction reaction. [ABSTRACT FROM AUTHOR]

A novel method, by which Cu was deposited on ferrite ceramics with arc-added glow discharge as a precursory procedure and then brazing the ferrite ceramics with vacuum glow discharge, was investigated. This new method can effectively suppress interfacial diffusion and brazing joint oxidation as well as maintain good adhesion in the joint due to low deposition and brazing temperature, the vacuum atmosphere effect, and the cathode sputter-cleaning action of the abnormal glow discharge plasma. The influence of the brazing process parameters on electrical and magnetic properties of the chip inductors is discussed. The optimal deposition and brazing process parameters are presented. Scanning electron microscope line scanning confirms the brazing electrode joints and detected the interfacial diffusion between the joints and the ferrite ceramics. [ABSTRACT FROM AUTHOR]

Presents a study that investigated the effect of Bi[sub2]O[sub3] additive on the densification, low-temperature firing and magnetic characteristics of a modified Z-type hexaferrite. Background on the use of magnetic ferrites in producing multilayer chip inductors; Examination of the magnetic properties of low-fired hexaferrites; Results and implications.

Examines the low-temperature sintering and electromagnetic properties of copper-modified Z-type hexaferrite. Reference to the substitution of copper for cobalt; Dependence of densification of copper-substituted hexaferrite on the amount of copper substitution and sintering temperatures; Homogeneousity of the microstructure.

Examines the effect of bismuth trioxide additive on the densification and electromagnetic properties of Co[sub 2]Z hexaferrite. Low-temperature sintering of the hexaferrite; Grain boundaries; Quality factor and cut-off frequency of the hexaferrite; Permeability.

Ubiquitin specific protease 26 (USP26) encodes a predicted protein containing his- and cys-domains that are conserved among deubiquitinating enzymes. USP26 is specifically expressed in testis tissue and is a potential infertility gene. In the present study, we performed genetic testing related to spermatogenesis impairment in a patient with idiopathic severe oligozoospermia to identify the cause. The patient underwent clinical examination and reproductive hormone testing. Genes associated with male infertility, including USP26, were assessed by targeted exome sequencing. A novel frameshift mutation, c.2195delT (p.Phe732Serfs*14), was identified in USP26. This frameshift mutation was located in residue 732 of USP26 gene, leading to loss of the conserved deubiquitinating enzyme His-domain and producing a truncated protein of 744 amino acids. Bioinformatics analysis revealed this mutation to be pathogenic. A novel framshift mutation c.2195delT (p.Phe732Serfs*14) in USP26 gene was reported to be associated with male infertility in a Chinese patient with severe oligozoospermia. [ABSTRACT FROM AUTHOR]

Chromosomal inversion is closely related to male infertility. Inversion carriers may produce abnormal gametes, which may lead to partial duplication/deletion of the embryonic chromosome and result in spontaneous abortion, a fetus with multiple anomalies, or birth of amalformed child. Genetic counselling remains challenging for these carriers in clinical practice. We report two male carriers with inversion of chromosome 10 and review 26 reported cases. In the first case, 46,XX,inv(10)(p13q22) of the fetal chromosome was found in prenatal diagnosis; this was inherited from the paternal side with 46XY,inv(10)(p13q22). Another case was a male carrier with inv(10)(q21.2q22.1). There have been 25 (89.3%) cases of pericentricinversion and three (10.7%) cases of paracentric inversion involving chromosome 10. Of 28 cases, nine were associated with pregestational infertility of the couples, while the other 19 cases were associated with gestational infertility of the couples or normozoospermia. The breakpoints at 10p15, 10p11, 10q11, and 10q21 were associated with pregestational infertility of the couples. The breakpoints at 10p15, 10p14, 10p13, 10p12, 10p11, 10q11, 10q21, 10q22, 10q23, 10q24, 10q25, and 10q26 were related to gestational infertility of the couples or normozoospermia. Although there is a high risk of infertility or recurrent miscarriages, carriers with inversion of chromosome 10 might produce healthy offspring. Natural pregnancy can be used as a choice for inversion carriers with recurrent spontaneous abortion. [ABSTRACT FROM AUTHOR]

Chromosomal microdeletions and microduplications likely represent the main genetic etiologies for children with developmental delay or intellectual disability. Through prenatal chromosomal microarray analysis, some microdeletions or microduplications can be detected before birth to avoid unnecessary abortions or birth defects. Although some microdeletions or microduplications of chromosome 5 have been reported, numerous microduplications remain undescribed. We describe herein a case of a 30-year-old woman carrying a fetus with a chromosome 5q21.1–q21.3 microduplication. Because noninvasive prenatal testing indicated a fetal chromosome 5 abnormality, the patient underwent amniocentesis at 22 weeks 4 days of gestation. Karyotyping and chromosomal microarray analysis were performed on amniotic fluid cells. Fetal behavioral and structural abnormalities were assessed by color and pulsed Doppler ultrasound. Clinical characteristics of the newborn were assessed during the follow-up. The left lateral ventricle appeared widened on ultrasound, but the infant appeared normal at birth. The 5q21.1–q21.3 microduplication in the fetus was inherited from his mother. There are seven genes in this duplication region, but their main functions are unclear. According to this case report, microduplication in this region could represent a benign mutation. Clinicians should pay attention to the breakpoints and the genes involved when counseling patients with microdeletions and microduplications. [ABSTRACT FROM AUTHOR]

Previous studies indicated that chromosome 9 translocations are involved in reduced male fertility and increased chance of miscarriage in the female partner. The aim of this study was to review the clinical features and genetic counselling requirements of infertile men carrying chromosome 9 translocations. This study analyzed fertile-age male carriers of chromosome 9 translocations, and included 12 clinical cases in our hospital. In our cases, three cases had oligozoospermia or severe oligozoospermia, while nine cases had normal semen. Of the latter nine cases, seven were associated with recurrent spontaneous abortions, and two produced a phenotypically normal child as confirmed by amniocentesis. Male chromosome 9 translocations and specific breakpoints from reported papers were searched using PubMed and CNKI database. A literature review identified 76 male patients who carried chromosome 9 translocations. Breakpoints at 9p12, 9p11, 9p10 and 9q34.1 were related to pregestational infertility, while breakpoints at 9p21, 9q10, 9q11, 9q13, 9q21.1, 9q22, 9q22.2, 9q22.3, 9q34, 9q34.2 and 9q34.3 exhibited gestational infertility. Chromosome translocations involving chromosome 9 lead to increased risk of miscarriage. Carriers of chromosome 9 translocations should be counselled to consider in vitro fertilization accompanied by preimplantation genetic diagnosis. [ABSTRACT FROM AUTHOR]

Singular point detection (SPD) for the determination of the anisotropy field (BA) using a conventional magnetometer is demonstrated.We then followthe composition dependence of BA in MnxGa using a combination of SPD measurements complemented by first-principles density functional theory (DFT) calculations. We find excellent quantitative agreement for 1.2 ⩽ x ⩽ 1.8, but observe a marked departure for x ⩽1.2. We suggest that the deviation from ideal behaviour might be associated with site disorder at low excess Mn. [ABSTRACT FROM AUTHOR]

Room temperature neutron powder diffraction has been used to investigate the chemical structure and magnetic ordering of a series of tetragonal (I4/mmm #139) MnxGa (1.15 ≤ x ≤ 2.0) alloys. Initially (x < 1.5) the excess Mn goes on the 2b site with vacancies appearing at the 2a site. For x > 1.5 Mn also appears on the 2a site. The manganese atoms on the 4d site carry an almost constant moment of 2.16(6) μB/Mn. The loss of magnetisation seen with increasing Mn content is shown to be the result of large (~ 3 μB/Mn), antiparallel Mn moments on the 2b, and later 2a sites, and not to a reduction of the Mn moment on the 4d sites. [ABSTRACT FROM AUTHOR]

Aquaporin-8 (AQP8) is a water channel expressed extensively in male and female reproductive systems. But its physiological functions are largely unknown. In the present study, we first found significantly increased number of offspring delivered by AQP8 mothers compared with wild-type mothers in cross-mating experiments. Comparison of ovulation in the two genotypes demonstrated that AQP8 ovaries released more oocytes (9.5 ± 1.9 vs. 7.1 ± 2.1 in normal ovulation and 37.8 ± 6.7 vs. 27.9 ± 5.7 in superovulation). Histological analysis showed increased number of corpus luteums in mature AQP8 ovaries, suggesting increased maturation and ovulation of follicles. By RT-PCR, western blot and immunohistochemistry analyses, we determined the expression of AQP8 in mouse ovarian granulosa cells. Granulosa cells isolated from AQP8 mice showed 45% of decreased membrane water permeability than wild-type mice. As the atresia of ovarian follicles is primarily due to apoptosis of granulosa cells, we analyzed the apoptosis of isolated granulosa cells from wild-type and AQP8 mice. The results indicated significantly lower apoptosis rate in AQP8 granulosa cells (21.3 ± 3.6% vs. 32.6 ± 4.3% in AQP8 granulosa cells). Taken together, we conclude that AQP8 deficiency increases the number of mature follicles by reducing the apoptosis of granulosa cells, thus increasing the fertility of female mice. This discovery may offer new insight of improving female fertility by reducing granulosa cell apoptosis through AQP8 inhibition. © IUBMB IUBMB Life, 62(11): 852-857, 2010. [ABSTRACT FROM AUTHOR]