Correlated Electrical Conductivities to Chemical Configurations of Nitrogenated Nanocrystalline Diamond Films

Diamond is one of the fascinating films appropriate for optoelectronic applications due to its wide bandgap (5.45 eV), high thermal conductivity (3320 W m−1·K−1), and strong chemical stability. In this report, we synthesized a type of diamond film called nanocrystalline diamond (NCD) by employing a physical vapor deposition method. The synthesis process was performed in different ratios of nitrogen and hydrogen mixed gas atmospheres to form nitrogen-doped (n-type) NCD films. A high-resolution scanning electron microscope confirmed the nature of the deposited films to contain diamond nanograins embedded into the amorphous carbon matrix. Sensitive spectroscopic investigations, including X-ray photoemission (XPS) and near-edge X-ray absorption fine structure (NEXAFS), were performed using a synchrotron beam. XPS spectra indicated that the nitrogen content in the film increased with the inflow ratio of nitrogen and hydrogen gas (IN/H). NEXAFS spectra revealed that the σ*C–C peak weakened, accompanied by a π*C=N peak strengthened with nitrogen doping. This structural modification after nitrogen doping was found to generate unpaired electrons with the formation of C–N and C=N bonding in grain boundaries (GBs). The measured electrical conductivity increased with nitrogen content, which confirms the suggestion of structural investigations that nitrogen-doping generated free electrons at the GBs of the NCD films.

Effect of an early intervention programme on low birthweight infants with cerebral injuries

OBJECTIVE

To determine the effect of an early intervention programme (EIP) on low birthweight infants with cerebral injuries.

METHODS

Subjects were 23 high-risk low birthweight infants (periventricular leukomalacia 15, intraventricular haemorrhage 5, both 3) receiving care in the neonatal intensive care unit (NICU) at Nagasaki University Hospital. Subjects were randomly assigned to the EIP group (n = 12) or the control group (n = 11). Participants in the EIP group received a Neonatal Behavioral Assessment scale (NBAS)-based intervention combined with developmental support designed to enhance the infants' development and the quality of the parent-infant relationship. The control group received routine medical nursing care without the EIP. The EIP began prior to discharge from the NICU and lasted until 6 months of corrected age. All children were examined on the NBAS preintervention and again at 44 weeks postconceptional age. Maternal anxiety status (STAI) and maternal feelings of confidence in dealing with her baby (LCC) were measured pre and postintervention. Mental and motor development was assessed postintervention using the Bayley Scale of Infant Development.

RESULTS

Orientation and State Regulation of infant behavioural profiles, the STAI and LCC scores significantly improved in the EIP group (mean difference (95% CI): Orientation 0.7 (0.4, 1.1), State Regulation 0.9 (0.3, 1.5), STAI -5.5 (- 9.1, -1.9, LCC 5.3 (4.2, 6.5)), but not in the control group. Bayley mental developmental index (MDI) score in the EIP group was higher than in the control group, but there was no significant difference between the two groups (mean difference (95% CI): MDI 8.5 (- 0.8, 17.8), PDI 6.7 (- 1.9, 15.4)).

CONCLUSION

The EIP has beneficial effects on neonatal neurobehavioural development and maternal mental health of low birthweight infants with cerebral injuries. This evidence suggests that short-term changes in maternal mental health and infant neurobehaviour promoted by an EIP may serve to initiate a positive interaction between parents and infants.

Concentration of granulocyte elastase in seminal plasma is not associated with sperm motility

Although elastase could affect sperm motility in vitro, secretory leukocytes protease inhibitor (SLPI) prevents sperm from being attacked by elastase. The authors investigated the correlations of elastase level with sperm motility and SLPI level in vivo. Semen samples (n = 116) were collected and centrifuged after semen analysis. Elastase and SLPI levels were determined by an enzyme immunosorbent assay. Samples were classified by elastase levels into low (<250 ng/mL), moderate (250-1,000 ng/mL), and high elastase groups (> or =1,000 ng/mL). Elastase levels (range, 2.8-23,974.4 ng/mL) were not associated with sperm motility. The median SLPI level in the high elastase group was 15,900 ng/mL (range, 2.860-46,900 ng/mL). However, there was no significant correlation between elastase and SLPI levels in seminal plasma. Since SLPI forms a 1:1 complex with elastase, these results suggest that seminal plasma has a sufficient amount of SLPI to protect spermatozoa from elastase.

Binding of human secretory leukocyte protease inhibitor in uterine cervical mucus to immunoglobulins: pathophysiology in immunologic infertility and local immune defense

OBJECTIVE

To identify an Fc receptor-like molecule in human cervical mucus.

DESIGN

Controlled experimental laboratory study.

SETTING

Department of Obstetrics and Gynecology, School of Medicine, University of Tokushima.

PATIENT(S)

Women undergoing treatment for infertility.

INTERVENTION(S)

Sodium dodecyl sulfate-polyacrylimide gel electrophoresis and Western blot were used for analysis.

MAIN OUTCOME MEASURE(S)

A water-insoluble protein with immunoglobulin-binding activity was purified from human cervical mucus by ammonium sulfate fractionation. The initial 21 amino acids of the N-terminus of the immunoglobulin-binding protein were determined and analyzed in a computer search for homology.

RESULT(S)

The purified fraction contained a 15-kd protein that binds immunoglobulin A, immunoglobulin M, and all subclasses of human immunoglobulin G as determined by Western blot analysis. The amino acid sequence of the N-terminus is identical to that of secretory leukocyte protease inhibitor. The capacity of secretory leukocyte protease inhibitor to bind immunoglobulins was confirmed by Western blot analysis.

CONCLUSION(S)

A component in human cervical mucus capable of binding immunoglobulins was identified as secretory leukocyte protease inhibitor. The capacity to bind immunoglobulins is a unique property of the protein, providing additional support for the contention that it plays an important physiologic role in local tissue defense mechanisms. It also is involved in the pathogenesis of immunologic infertility by trapping sperm in the cervical mucus.

Complement-inhibiting activity of human seminal plasma and semen quality

Human seminal plasma (SP) contains potent complement inhibitors. This study examined the complement-inhibiting activity of individual SP samples from 118 patients with infertility and analyzed them in relation to various semen parameters. When 25% complement-inhibiting activity was considered the cut off value, less than 1 SD unit from the mean percentage of inhibition of SP samples with normal semen quality, 32 samples (27%) showed low inhibiting activity. Among the lower group, incidences of patients with asthenozoospermia (66%) and oligozoospermia (31%) were significantly (p < .01) higher than those (36 and 10%) in the group whose SP showed significant inhibiting activity. Partial characterization revealed that the component responsible for complement inhibition was heat labile, trypsin resistant, high molecular weight (>10 kD) glycoprotein that can inhibit alternative as well as classical complement pathways. Furthermore, since in the majority of SP samples the anticomplementary activity was blocked by monoclonal antibody against membrane cofactor protein (MCP) or decay accelerating factor (DAF), the complement-inhibiting factors that were identified are likely to be MCP and/or DAF, which are known to be present in human SP. These results suggest that complement-regulatory proteins in SP such as MCP and DAF may protect sperm cells against complement attack in the male reproductive tract.