Frequency of subnormal hypoosmotic swelling tests increase with advancing age of the male

PURPOSE

To determine if there is an increased frequency of abnormal hypoosmotic swelling (HOS) tests when testing semen in males of advanced reproductive age.

METHODS

Ten-year retrospective review according to six age groups (< or = 29.9, 30-34.9, 35-39.9, 40-44.9, 45.0-49.9, and > or = 50).

RESULTS

Compared to males < 35 years old, the frequency of HOS scores < 50% doubles in males 45-49.9 and quadruples in males > or = 50.

CONCLUSIONS

Males with low HOS scores despite having no problem with fertilization of the oocytes rarely achieve a pregnancy because of embryo implantation defects unless intracytoplasmic sperm injection (ICSI) is performed. Thus at least one abnormality seen in sperm of males of advanced reproductive age is correctable by performing in vitro fertilization with ICSI.

Low hypoosmotic swelling test scores correlate better with lower percent motility than any other abnormal semen parameters

PURPOSE

To determine if any single abnormal semen parameter is associated with low hypoosmotic swelling (HOS) test scores.

METHODS

A retrospective review evaluating males with single sperm defects of sperm concentration, % progressive motility, morphology using strict criteria, and antisperm antibodies. The percentage of these males with HOS test scores < 50% was then determined.

RESULTS

By far the abnormal semen parameter most associated with a subnormal HOS test was poor motility.

CONCLUSIONS

Though we believe that the simple inexpensive HOS test should be performed routinely when performing semen analysis, it is especially important to evaluate in males with poor motility since simple intrauterine insemination will not allow pregnancies.

The majority of males with subnormal hypoosmotic test scores have normal vitality

PURPOSE

To determine if males with low hypoosmotic swelling (HOS) test scores may have normal vitality tests.

METHODS

Retrospective nine-year review of initial semen analyses evaluating vitality and HOS tests.

RESULTS

Only 12.5% (45/361) of males with low HOS test scores have low vitality.

CONCLUSIONS

WHO seems to treat vitality and HOS as equal tests. We disagree and find that structural defects of the sperm membrane are much less common than functional impairment of the sperm membrane. Since a male with an HOS test score < 50% will rarely achieve a pregnancy with intercourse, intrauterine insemination, or IVF with conventional insemination it is important to check for the HOS test not viability because the HOS test can be easily corrected with ICSI.

Screening for depression in nursing homes: Validity of the WHO (Five) Well-Being Index

Introduction

Depression is common in nursing home residents, but is still underrecognized. Screening for depression could be a first step to increase recognition rates within this high-risk group.

Objectives

Therefore, we investigated the validity of the WHO (Five) Well-Being Index (WHO-5) for early detection of depression in nursing home residents.

Methods

The Structural Clinical Interview for DSM-IV (SCID) was used as the gold standard for the validation of the WHO-5. The diagnoses covered in this assessment were both current major depression (MD) as well as minor depression (MinD) according to DSM-IV research criteria.

Results

In our sample of 92 nursing home residents in Munich aged 65–97 years, (73.9% female, 26.1% male) 14.1% fulfilled the criteria of MinD, and again 14.1% fulfilled the criteria of MD in the SCID. Overall diagnostic validity (area under the ROC curve) of the WHO-5 was 90.1% (95% confidence interval: 83.5%–96.7%). The World Health Organization's recommended cut-off-point of 13 yielded a sensitivity of 92.3% for the category of ‘MinD or MD’, and a specificity of 74.2%. Corresponding values for an adapted cut-off point of 12 are 92.3% and 78.7%, respectively.

Conclusions

The diagnostic accuracy of the WHO-5 in our study is promising. The WHO-5 might be an efficient screening tool for nursing home residents, especially with the adapted cut-off point, but results have to be replicated in a larger sample.

A panel of high resolution melting (HRM) technology-based assays with direct sequencing possibility for effective mutation screening of EGFR and K-ras genes

Background: Increasing data from clinical trials support EGFR and K-ras mutation status as predictive markers of tumour response to EGFR-targeted therapies. Consequently, rapid and reliable mutation screening assays are demanded to guide rational use of EGFR-targeted therapies.

Methods: In this study, we describe the development of high resolution melting (HRM) technology-based assays with direct sequencing confirmation possibility for mutation screening of the EGFR gene (exons 19, 20 and 21) in routine diagnostic specimens, and compared assay findings to those of conventional nested-PCR following cycle-sequencing.

Results: In reconstruction experiments, each HRM assay following sequencing demonstrated a sensitivity of ≤5% of mutated DNA in a background of wild-type DNA. The panel of EGFR HRM assays following sequencing applied to a series of genomic DNA samples isolated from 68 FFPE NSCLC specimens correctly identified all EGFR mutations that were previously found by nested-PCR following cycle-sequencing. The HRM approach additionally scored two mutations not detected by the conventional assay.

Complementary HRM following sequencing for K-ras revealed three mutations. EGFR and K-ras mutations were mutually exclusive.

Conclusions: The panel of designed HRM assays with direct reflex sequencing possibility provides an effective method for mutation screening of EGFR and K-ras genes in routine diagnostic specimens, thereby allowing the selection of the treatment of choice in clinical practice.

A fast, sensitive and accurate high resolution melting (HRM) technology-based assay to screen for common K-ras mutations

Background: Increasing evidence points to a negative correlation between K-ras mutations and patient’s response to, or survival benefit after, treatment with EGFR-inhibitors. Therefore, rapid and reliable assays for mutational analysis of the K-ras gene are strongly needed.

Methods: We designed a high resolution melting (HRM) technology-based approach followed by direct sequencing to determine K-ras exon 1 (codons 12/13) tumour genotype.

Results: Reconstruction experiments demonstrated an analytical sensitivity of the K-ras exon 1 HRM assay following sequencing of 1.5–2.5% of mutated DNA in a background of wild-type DNA. Assay reproducibility and accuracy were 100%. Application of the HRM assay following sequencing onto genomic DNA isolated from formalin-fixed paraffin-embedded tumour specimens of non-small cell lung cancer (n=91) and colorectal cancer (n=7) patients revealed nucleotide substitutions at codons 12 or 13, including a homozygous mutation, in 33 (34%) and 5 (5%) cases, respectively. Comparison to conventional nested-PCR following cycle-sequencing showed an overall high agreement in genotype findings (kappa value of 0.96), with more mutations detected by the HRM assay following sequencing.

Conclusion: HRM allows rapid, reliable and sensitive pre-screening of routine diagnostic specimens for subsequent genotyping of K-ras mutations, even if present at low abundance or homozygosity, and may considerably facilitate personalized therapy planning.

Surface-chemistry-driven actuation in nanoporous gold

Although actuation in biological systems is exclusively powered by chemical energy, this concept has not been realized in man-made actuator technologies, as these rely on generating heat or electricity first. Here, we demonstrate that surface-chemistry-driven actuation can be realized in high-surface-area materials such as nanoporous gold. For example, we achieve reversible strain amplitudes of the order of a few tenths of a per cent by alternating exposure of nanoporous Au to ozone and carbon monoxide. The effect can be explained by adsorbate-induced changes of the surface stress, and can be used to convert chemical energy directly into a mechanical response, thus opening the door to surface-chemistry-driven actuator and sensor technologies.

Surface stress-charge response of a (111)-textured gold electrode under conditions of weak ion adsorption

We report a cantilever bending investigation into the variation of surface stress, f, with surface charge density, q, for (111)-textured thin films of gold in aqueous NaF and HClO 4. The graphs of f(q) are highly linear, and the surface stress-charge coefficients, d f/d q, are -1.95 V for 7 mM NaF and -2.0 V for 10 mM HClO 4 near the potential of zero charge. These values exceed some previously published experimental data by a factor of 2, but they agree with recent ab initio calculations of the surface stress-charge response of gold in vacuum.

Shear-induced tilt in smectic-A elastomers

Smectic-A elastomers combine the positional long-range order of mesogenic molecules in one dimension with the rubber elasticity of a polymer network. While the influence of uniaxial mechanical fields on the phase structure has been investigated intensively during recent years, the impact of shear forces on the orientation of mesogens remains unclear. We present x-ray experiments under shear strain, showing an induced macroscopic tilt depending on the applied shear angle and geometry of the setup.

Serotypes and virutypes of enteropathogenic and enterohaemorrhagic Escherichia coli strains from stool samples of children with diarrhoea in Germany

AIMS

To investigate the prevalence of traditional and emerging types of enteropathogenic (EPEC) and enterohaemorrhagic Escherichia coli (EHEC) strains in stool samples from children with diarrhoea and to characterize their virulence genes involved in the attaching and effacing (A/E) phenotype.

METHODS AND RESULTS

Serological and PCR-based methods were used for detection and isolation of EPEC and EHEC strains from 861 stool samples from diarrhoeic children. Agglutination with traditional EPEC and EHEC O-group-specific antisera resulted in detection of 38 strains; 26 of these carried virulence factors of EPEC or EHEC. PCR screening for the eae gene resulted in isolation of 97 strains, five carried genes encoding Shiga toxins (stx), one carried the bfpA gene and 91 were atypical EPEC. The 97 EPEC and EHEC strains were divided into 36 O-serogroups and 21 H-types, only nine strains belonged to the traditional EPEC O-groups O26, O55, O86 and O128. In contrast, EPEC serotypes O28:H28, O51:H49, O115:H38 and O127:H40 were found in multiple cases. Subtyping the virulence factors intimin, Tir and Tir-cytoskeleton coupling effector protein (TccP)/TccP2 resulted in further classification of 93.8% of the 97 strains.

CONCLUSIONS

Our findings show a clear advantage of the eae-PCR over the serological detection method for identification of EPEC and EHEC strains from human patients.

SIGNIFICANCE AND IMPACT OF THE STUDY

Molecular detection by the eae-PCR followed by serotyping and virutyping is useful for monitoring trends in EPEC and EHEC infections and to discover their possible reservoirs.

[Heat shock protein 90 alpha und beta are overexpressed in multiple myeloma cells and critically contribute to survival]

HSP90's are overexpressed in different cancer types and they probably are required to sustain aberrant signalling in malignant cells. Recently, pharmacological inhibition of HSP90 was found to suppress growth of myeloma cell lines and in primary myeloma cells. Therefore, we wanted to investigate the role of HSP90alpha and HSP90beta in the pathogenesis of malignant myeloma (MM) in more detail. Immunohistochemistry was employed to examine the expression of HSP90alpha and HSP90beta in MM. The importance of HSP90 for survival of MM -cells was investigated by SiRNA-mediated knockdown of HSP90 and blockade of the IL-6R/STAT3 and the MAPK signaling pathways in vitro. HSP90alpha and HSP90beta were overexpressed in majority of investigated MM cases, but not in MGUS or in normal plasma cells. SiRNA-mediated knockdown of HSP90 or treatment with the novel HSP90 inhibitor 17-DMAG attenuated the levels of STAT3 and phospho-ERK and decreased the viability of MM cells. The knockdown of HSP90alpha was sufficient to induce apoptosis. This effect was strongly increased when both HSP90s were targeted, indicating a cooperation of both. HSP90 critically contributes to myeloma survival in the context of its microenvironment and therefore strengthen the potential value of HSP90 as a therapeutic target.