Energy-resolved neutron imaging options at a small angle neutron scattering instrument at the Australian Center for Neutron Scattering.

Energy-resolved neutron imaging experiments conducted on the Small Angle Neutron Scattering (SANS) instrument, Bilby, demonstrate how the capabilities of this instrument can be enhanced by a relatively simple addition of a compact neutron counting detector. Together with possible SANS sample surveying and location of the region of interest, this instrument is attractive for many imaging applications. In particular, the combination of the cold spectrum of the neutron beam and its pulsed nature enables unique non-destructive studies of the internal structure for samples that are opaque to other more traditional techniques. In addition to conventional white beam neutron radiography, we conducted energy-resolved imaging experiments capable of resolving features related to microstructure in crystalline materials with a spatial resolution down to ∼0.1 mm. The optimized settings for the beamline configuration were determined for the imaging modality, where the compromise between the beam intensity and the achievable spatial resolution is of key concern.

PTPIP51 levels in glioblastoma cells depend on inhibition of the EGF-receptor.

Protein tyrosine phosphatase interacting protein 51 (PTPIP51) is upregulated in glioblastoma multiforme (GBM) and expression levels correlate with the grade of malignancy in gliomas. A similar correlation was reported for its interacting partner 14-3-3ß, which has been shown to facilitate the interaction of PTPIP51 with cRAF (Raf1). Since the interaction of these signalling partners stimulates growth factor signalling downstream of the epidermal growth factor receptor (EGFR), a major drug target in GBM, we here investigated the impact of EGFR inhibition by small molecule inhibitors or monoclonal antibody on PTPIP51. The effect of EGFR inhibition on PTPIP51 mRNA, protein expression and its interaction profile in GBM was analyzed using the U87 cell line as model system. The transferability of the results to in vivo conditions was evaluated in cultured tumour cells from GBM patients. Cells were treated either to the small molecule tyrosine kinase inhibitor of EGFR Gefitinib or the monoclonal antibody Cetuximab in a time and dose dependent manner. Gefitinib treatment decreased the proliferation rate and induced apoptosis in U87 and primary tumour cells. The PTPIP51 interaction profile changed in correlation to the applied Gefitinib. Despite unchanged mRNA levels PTPIP51 protein was reduced. In contrast, treatment with Cetuximab had no effects on PTPIP51 expression. In conclusion, our results demonstrate the impact of EGFR inhibition by Gefitinib on PTPIP51 protein expression, a downstream regulator of MAPK signalling. These data will serve as a basis to unravel the precise role of PTPIP51-mediated signalling in GBM and its potential implications for Gefitinib-mediated therapy in future studies.

Halitosis--a common medical and social problem. A review on pathology, diagnosis and treatment.

Bad breath is a condition that has health and social implications. This paper provides a comprehensive review of the classification of halitosis, it's etiology, it's prevalence, diagnosis and treatment strategies for the condition. Halitosis is affecting about 25-30% of world's population. It includes categories of genuine halitosis, pseudo-halitosis and halitophobia. It is believed that in 80-90% of cases halitosis origins in the oral cavity and the most common causes are: gingival pathologies, caries and poor oral hygiene. Extraoral sources of halitosis are responsible for 10-20% of all cases and are caused by poor diet, alcohol abuse, tobacco smoking, certain drugs and diseases of other parts of digestive tract as well as some systemic conditions. Diagnostics of halitosis includes subjective methods (examiner's sense of smell) and objective methods (instrumental analysis). Simple, subjective examination is considered a "golden standard" in clinical practice. In case of pathological halitosis identifying the direct cause of halitosis is essential. After excluding, or after successful treatment, of all oral pathologies, in case of remaining fetor ex ore identification and treatment of halitosis often requires multidisciplinary approach. Many unknowns remain in causes and mechanisms of halitosis. It can significantly impair quality of life, social interactions, lead directly to depression,low self-esteem or other mood disorders, therefore it is important to properly identify, treat and continue research on halitosis.

Mixed testicular atrophy related to atherosclerosis: first lessons from the ApoE(-/-)/ LDL receptor(-/-) double knockout mouse model.

Age-related testicular changes are associated with declining spermatogenesis and testosterone levels. A relationship to atherosclerosis has never been investigated systematically. The ApoE(-/-)/LDL receptor(-/-) double knockout mouse model, providing a remarkable homology to human atherosclerosis, is an ideal tool to investigate spermatogenetic alterations in this context. Testes (n = 10) from ApoE(-/-)/LDL receptor(-/-) double knockout mice at the age of 80 weeks were perfused in vivo with contrast agent, harvested and scanned with micro-CT at (4.9 µm³) voxel size. Testes (n = 8) of C57/BL mice at the same age served as controls. Testis volume (mm³) and total vascular volume fraction (mm³) were quantified using micro-CT. Serum testosterone levels were determined. Testicular histology and epididymal sections were analysed for tubular structure, spermatogenetic scores and sperm count. The expression of protamine 2 as a marker for elongated spermatids, inflammation markers (CD4, F4/80) and hypoxia inducible factor 1 alpha (HIF1 alpha) were investigated using immunohistochemistry. ApoE(-/-)/LDL receptor(-/-) double knockout mice exhibit diminished testis and vascular volume fraction with respect to that of controls (p < 0.001). These findings were associated with a reduction of testosterone levels (p < 0.001). Mixed atrophy was present in 41% of the seminiferous tubuli in ApoE(-/-)/LDL receptor(-/-) double knockout mice at the age of 80 weeks. Sperm counts from the epididymis demonstrated a significant decrease in ApoE(-/-)/LDL receptor(-/-) double knockout mice (p < 0.001). In addition, sperm specific protamine 2 expression was decreased in testicular tissue and epididymis of ApoE(-/-)/LDL receptor(-/-) double knockout mice compared with that of control mice. Peritubular inflammatory infiltration and the expression of the hypoxia related marker was observed. Mixed testicular atrophy in ApoE(-/-)/LDL receptor(-/-) double knockout mice is linked to reduced testis volume, vascular volume fraction and low testosterone serum levels, suggesting a direct relation between atherosclerosis and disturbed spermatogenesis.

Presence of histone H3 acetylated at lysine 9 in male germ cells and its distribution pattern in the genome of human spermatozoa.

During spermatogenesis, approximately 85% of histones are replaced by protamines. The remaining histones have been proposed to carry essential marks for the establishment of epigenetic information in the offspring. The aim of the present study was to analyse the expression pattern of histone H3 acetylated at lysine 9 (H3K9ac) during normal and impaired spermatogenesis and the binding pattern of H3K9ac to selected genes within ejaculates. Testicular biopsies, as well as semen samples, were used for immunohistochemistry. Chromatin immunoprecipitation was performed with ejaculated sperm chromatin. HeLa cells and prostate tissue served as controls. Binding of selected genes was evaluated by semiquantitative and real-time polymerase chain reaction. Immunohistochemistry of H3K9ac demonstrated positive signals in spermatogonia, spermatocytes, elongating spermatids and ejaculated spermatozoa of fertile and infertile men. H3K9ac was associated with gene promoters (CRAT, G6PD, MCF2L), exons (SOX2, GAPDH, STK11IP, FLNA, PLXNA3, SH3GLB2, CTSD) and intergenic regions (TH) in fertile men and revealed shifts of the distribution pattern in ejaculated spermatozoa of infertile men. In conclusion, H3K9ac is present in male germ cells and may play a role during the development of human spermatozoa. In addition, H3K9ac is associated with specific regions of the sperm genome defining an epigenetic code that may influence gene expression directly after fertilisation.

Neutron diffraction residual strain measurements in nanostructured hydroxyapatite coatings for orthopaedic implants.

The failure of an orthopaedic implant can be initiated by residual strain inherent to the hydroxyapatite coating (HAC). Knowledge of the through-thickness residual strain profile in the thermally sprayed hydroxyapatite coating/substrate system is therefore important in the development of a new generation of orthopaedic implants. As the coating microstructure is complex, non-destructive characterization of residual strain, e.g. using neutron diffraction, provides a useful measure of through thickness strain profile without altering the stress field. This first detailed study using a neutron diffraction technique, non-destructively evaluates the through thickness strain measurement in nanostructured hydroxyapatite plasma sprayed coatings on a titanium alloy substrate (as-sprayed, heat treated, and heat treated then soaked in simulated body fluid (SBF)). The influence of crystallographic plane orientation on the residual strain measurement is shown to indicate texturing in the coating. This texturing is expected to influence both the biological and fracture response of HA coatings. Results are discussed in terms of the influence of heat-treatment and SBF on the residual stress profile for these biomedical coatings. The results show that the through thickness residual strain in all three coatings was different for different crystallographic planes but was on average tensile. It is also concluded that the heat-treatment and simulated body fluid exposure had a significant effect on the residual strain profile in the top layers of HAC.

PTPIP51, a positive modulator of the MAPK/Erk pathway, is upregulated in glioblastoma and interacts with 14-3-3ß and PTP1B in situ.

Glioblastoma multiforme (GBM) is the most common and most malignant primary brain tumour. Protein tyrosine phosphatase interacting protein 51 (PTPIP51) is an interaction partner of 14-3-3ß, which correlates with the grade of malignancy in gliomas. In this study PTPIP51 and its interacting partners 14-3-3ß, PTP1B, c-Src, Raf-1 as well as EGFR were investigated in human glioblastoma. Twenty glioblastoma samples were analyzed on transcriptional and translational level by immunohistochemistry, in situ hybridization and RT-PCR. To compare PTPIP51 expression in gliomas of different malignancies, quantitative RT-PCR for grade II astrocytoma and GBM samples was employed. Additionally, we analyzed the correlation between PTPIP51 and 14-3-3ß transcription, and checked for in situ interaction between PTPIP51 and 14-3-3ß and PTP1B, respectively. PTPIP51 and 14-3-3ß mRNA showed a tumour grade dependent upregulation in gliomas. Glioblastoma cells displayed a strong immunoreaction of PTPIP51, which co-localized with 14-3-3ß and PTP1B. The duolink proximity ligation assay corroborated a direct in situ interaction of PTPIP51 with both proteins, known to interact with PTPIP51 in vitro. The in vitro interacting partners Raf-1 and c-Src showed a partial co-localization. Besides, immune cells located in capillaries or infiltrating the tumour tissue and endothelial cells of pseudoglomerular vessels revealed a high PTPIP51 expression. The upregulation of PTPIP51 and its connection with the EGFR/MAPK pathway by 14-3-3ß via Raf-1 and by PTP1B via c-Src, argue for a functional role of PTPIP51 in the pathogenesis of human glioblastoma.

Shear stiffness in nanolaminar Ti3SiC2 challenges ab initio calculations.

Nanolaminates such as the M(n + 1)AX(n) (MAX) phases are a material class with ab initio derived elasticity tensors published for over 250 compounds. We have for the first time experimentally determined the full elasticity tensor of the archetype MAX phase, Ti(3)SiC(2), using polycrystalline samples and in situ neutron diffraction. The experimental elastic constants show extreme shear stiffness, with c(44) more than five times greater than expected for an isotropic material. Such shear stiffness is quite rare in hexagonal materials and strongly contradicts the predictions of all published MAX phase elastic constants derived from ab initio calculations. It is concluded that second order properties such as elastic moduli derived from ab initio calculations require careful experimental verification. The diffraction technique used currently provides the only method of verification for the elasticity tensor for the majority of new materials where single crystals are not available.

Residual stress distribution in steel butt welds measured using neutron and synchrotron diffraction.

70 keV synchrotron radiation and thermal neutrons have been employed to investigate the residual stress characteristics in a fully restrained, steel, butt weld. The focus is on the values of the subsurface and through-thickness strain/stress variation in the middle of the weld. The advantages and limitations of the techniques have been addressed, in relation to the gauge volume, the stress-free reference sample and positioning. The measurement of residual stress around the weld achieved in this work significantly improves the resolution at which residual stress in welded components has been determined.

[TESE and mTESE. Therapeutic options in male infertility due to testicular azoospermia]. / TESE und M-TESE. Therapieoption bei infertilen Männern mit testikulärer Azoospermie.

Modern techniques of testicular sperm extraction (TESE) make it possible for an infertile man to father a child. The operations are standardized to a large extent and the underlying morphological alterations of spermatogenesis also appear to be sufficiently known. Current research is focused on prognostic factors for the testicular material that determine the sperm retrieval rate and success rates after in vitro fertilization/intracytoplasmic sperm injection (IVF-ICSI).TESE and microTESE are accepted standard operations for testicular sperm retrieval for IVF/ICSI. Predictions for effective sperm recovery are addressed.