Risk factors for male patients with gonorrhoea complicated by inflammation of the paraurethral glands around the external urethral orifice

Gonococcal inflammation of paraurethral glands around the external urethral orifice is a local complication of gonorrhoea in men. To investigate the risk factors for this complication we compared prepuce factors, Chlamydia trachomatis infection, demographic data and behavioural indicators of gonorrhoeal patients with and without this complication. Results showed that a prolonged disease course of gonorrhoea, sexual intercourse during gonorrhoea, repeated squeezing of the penis and a redundant prepuce were risk factors for this complication.

Hydrogeo-chemical impacts of air sparging remediation on a semi-confined aquifer: evidences from field monitoring and modeling

Air sparging (AS) was explored for remediation of a petroleum contaminated semi-confined groundwater system in NE China. Physical, hydro-chemical and hydraulic behaviors in subsurface environment during AS were investigated with support of modeling to understand the hydrogeo-chemical impacts of AS on the aquifer. The responses of groundwater, dissolved oxygen and temperature indicated that the radius of influence of AS was up to 8-9 m, and a 3D boundary of the zone of influence (ZOI) was accordingly obtained with volume of 362 m(3). Water mounding unlike normal observations was featured by continuous up-lift and blocked dissipation. AS induced water displacement was calculated showing no obvious spreading of contaminant plume under this AS condition. Slug tests were employed before and after AS to reveal that the physical perturbation led to sharp increase in permeability and porosity. Modeling indicated that the regional groundwater flow field was not affected by AS except the physical perturbation in ZOI. Hydro-chemically increase of pH and Eh, and reduction of TDS, electrical conductivity and bicarbonate were observed in ZOI during AS. PHREEQC modeling inferred that these chemical phenomena were induced by the inorganic carbon transfer during air mixing.

Nuclear receptors and AMPK: resetting metabolism

Obesity, and in particular central adiposity, is a key feature of metabolic syndrome, which includes trends toward increased triglycerides, insulin resistance, high blood pressure, hypercholesterolemia, and heart disease. It has a prevalence of 25% or more and is a dominant component of the health care budgets in Western societies. In addition to genetic causes, high-fat diets and disrupted sleep patterns have major influences on the development of metabolic syndrome. Recent studies have demonstrated active roles for the nuclear receptor superfamily and the energy-sensing kinase adenosine monophosphate (AMP)-activated protein kinase (AMPK) in regulating metabolism and circadian rhythm. In this chapter, we review these findings and attempt to develop a better understanding of the interplay between metabolism and circadian rhythm and their coordinated regulation by nuclear receptors and AMPK. This supraregulatory network may be considered a target for novel therapeutic applications against metabolic syndrome.

The role of estrogen and estrogen receptors in chemoresistance

Drug resistance is one of the major obstacles limiting the success of cancer chemotherapy. Biological mechanisms contributing to drug resistance may be present de novo and related to inherent features or may be raised after exposure to anticancer drugs. In recent years, both clinical observations and experimental studies suggested that steroid hormones and their receptors might also affect the therapeutic efficacy of antineoplastic drugs. Estrogens and estrogen receptors (ER) are well-known for their critical roles in the development and progression of breast tumors. It has long been known that breast tumors expressing ERα protein (ERα+) behave in a fundamentally different fashion than ERα-negative (ERα-) tumors with regard to their responses to hormonal therapy. Data obtained from both laboratory and clinical investigations suggested that some chemotherapeutic agents are clearly less effective in ERα+ tumors than ERα- tumors, although the mechanisms of ERα-mediated chemoresistance are not entirely clear. Moreover, recent studies from our laboratory and others demonstrated that the combination of antiestrogenic agents with chemotherapeutic drugs is of significant therapeutic benefit in ERα+ breast cancer over chemotherapy alone. In addition, the ERα-derived peptides, microRNAs specifically targeting ERα, as well as agents targeting estrogen-related receptors (ERRs) may hold promise to sensitize ERα+ breast tumors to chemotherapy. Considering that ERs are expressed in ˜ 65% of human breast cancer, the ERα-mediated chemoresistance has become a big challenge for clinical treatment. The hope to overcome this drug resistance relies on further clarification of specific pathways or molecules contributing to the resistance. More exhaustive and systematic studies are essential to reach deeper understandings on the underlying mechanisms and to develop novel approaches to sensitize ERα+ breast tumors to chemotherapy.

Converting steady laminar flow to oscillatory flow through a hydroelasticity approach at microscales

We report a hydroelasticity-based microfluidic oscillator that converts otherwise steady laminar flow to oscillatory flow. It incorporates an elastic diaphragm to enhance nonlinearity of the flow. Negative differential flow resistance is observed. High-frequency oscillatory flow is produced passively through interactions among hydrodynamic, elastic and inertial forces, without resorting to external actuators and control equipment. Driven by fluid flow and pressure, this device can operate in either steady laminar flow or oscillatory flow states, or work as a valve. Its applications for flow control and operation, and mixing enhancement are demonstrated.

Comparative proteomics study of freshly isolated, in vitro cultured, and proliferating islet preparation cells

BACKGROUND

In vitro islet expansion has recently drawn interest for its potential application in diabetes therapy, while how islet cells adapt to in vitro circumstances is not quite clear.

AIM

Proteomics changes of cultivated islet cells under different conditions were examined in this study.

MATERIAL/SUBJECTS AND METHODS

A comparative proteomics study was performed on fresh isolated islet cells, cultured cells and in vitro proliferating islet cells stimulated by basic fibroblast growth factor via electrophoresis and liquid chromatography in tandem with mass spectrometry.

RESULTS

In total, 1897 proteins were identified in this study. Hierarchical analysis revealed substantial changes in the proteome during cultivation but relatively less difference between different culture conditions. Over 100 proteins showed significantly different expression levels between groups, most of which are involved in metabolism or cell process pathways. Overall, the detected proteins were involved in 152 known pathways. Furthermore, in-depth investigation suggested that some proteins, such as extracellular signal-regulated protein kinases and Rac, might play key roles in the proliferation, apoptosis, and differentiation of in vitro cultured islet cells.

CONCLUSION

We established comparative proteome references of fresh and cultured islet cells, which could provide useful information for future islet transplantation strategy.

Electron Transport Suppression from Tip-π State Interaction on Si(100)-2 × 1 Surfaces

We investigate the electron transport between a scanning tunneling microscope tip and Si(100)-2 × 1 surfaces with four distinct configurations by performing calculations using density functional theory and the nonequilibrium Green's function method. Interestingly, we find that the conducting mechanism is altered when the tip-surface distance varies from large to small. At a distance larger than the critical value of 4.06 Å, the conductance is increased with a reduction in distance owing to the π state arising from the silicon dimers immediately under the tip; this in turn plays a key role in facilitating a large transmission probability. In contrast, when the tip is closer to the substrate, the conductance is substantially decreased because the π state is suppressed by the interaction with the tip, and its contribution in the tunneling channels is considerably reduced.

Intrinsic optical properties of vanadium dioxide near the insulator-metal transition

We studied the insulator-metal transition (IMT) in single-domain, single crystalline vanadium dioxide (VO(2)) microbeams with infrared microspectroscopy. The unique nature of such samples allowed us to probe the intrinsic behavior of both insulating and metallic phases in the close vicinity of IMT, and investigate the IMT driven by either strain or temperature independently. We found that the VO(2) insulating band gap narrows rapidly upon heating, and the infrared response undergoes an abrupt transition at both strain- and temperature-induced IMT. The results are consistent with recent studies attributing the opening of VO(2) insulating band gap to a correlation-assisted Peierls transition.

The heme oxygenase system and oral diseases

Oral Diseases (2011) 17, 252-257 Heme oxygenase (HO) system catabolizes heme into three products: carbon monoxide (CO), biliverdin/bilirubin and free iron, which consists of three forms identified to date: the oxidative stress-inducible protein HO-1 and the constitutive isozymes HO-2 and HO-3. HO has been involved in many physiological and pathophysiological processes, ranging from Alzheimer's disease to cancer. The interest in HO system by scientists and clinicians involved with the oral and maxillofacial region is fairly recent, and few papers currently cited on HO relate to diseases in this anatomical area. This review will focus on the current understanding of the physiological significance of HO-1 induction and its possible roles in the oral diseases studied to date. The implications for possible therapeutic manipulation of HO are also discussed.

Extended mapping and exploration of the vanadium dioxide stress-temperature phase diagram

Single-crystal micro- and nanomaterials often exhibit higher yield strength than their bulk counterparts. This enhancement is widely recognized in structural materials but is rarely exploited to probe fundamental physics of electronic materials. Vanadium dioxide exhibits coupled electronic and structural phase transitions that involve different structures existing at different strain states. Full understanding of the driving mechanism of these coupled transitions necessitates concurrent structural and electrical measurements over a wide phase space. Taking advantages of the superior mechanical property of micro/nanocrystals of VO(2), we map and explore its stress-temperature phase diagram over a phase space that is more than an order of magnitude broader than previously attained. New structural and electronic aspects were observed crossing phase boundaries at high-strain states. Our work shows that the actively tuning strain in micro/nanoscale electronic materials provides an effective route to investigate their fundamental properties beyond what can be accessed in their bulk counterpart.