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Bio-inspired nanostructures have demonstrated highly efficient mechano-bactericidal performances with no risk of bacterial resistance; however, they are prone to become contaminated with the killed bacterial debris. Herein, a biocompatible mechano-bactericidal nanopatterned surface with salt-responsive bacterial releasing behavior is developed by grafting salt-responsive polyzwitterionic (polyDVBAPS) brushes on a bio-inspired nanopattern surface. Benefiting from the salt-triggered configuration change of the grafted polymer brushes, this dual-functional surface shows high mechano-bactericidal efficiency in water (low ionic strength condition), while the dead bacterial residuals can be easily lifted by the extended polymer chains and removed from the surface in 1 M NaCl solution (high ionic strength conditions). Notably, this functionalized nanopatterned surface shows selective biocidal activity between bacterial cells sand eukaryotic cells. The biocompatibility with red blood cells (RBCs) and mammalian cells was tested in vitro. The histocompatibility and prevention of perioperative contamination activity were verified by in vivo evaluation in a rat subcutaneous implant model. This nanopatterned surface with bacterial killing and releasing activities may open new avenues for designing bio-inspired mechano-bactericidal platforms with long-term efficacy, thus presenting a facile alternative in combating perioperative-related bacterial infection. Bioinspired nanostructured surfaces with noticeable mechano-bactericidal activity showed great potential in moderating drug-resistance. However, the nanopatterned surfaces are prone to be contaminated by the killed bacterial debris and compromised the bactericidal performance. In this study, we provide a dual-functional antibacterial conception with both mechano-bactericidal and bacterial releasing performances not requiring external chemical bactericidal agents. Additionally, this functionalized antibacterial surface also shows selective biocidal activity between bacteria and eukaryotic cells, and the excellent biocompatibility was tested in vitro and in vivo. The new concept for the functionalized mechano-bactericidal surface here illustrated presents a facile antibiotic-free alternative in combating perioperative related bacterial infection in practical application. [Display omitted] [ABSTRACT FROM AUTHOR]

Obesity and related diseases are becoming a growing risk for public health around the world due to the westernized lifestyle. Sema7A, an axonal guidance molecule, has been known to play a role in neurite growth, bone formation, and immune regulation. Whether Sema7A participates in obesity and metabolic diseases is unknown. As several SNPs in SEMA7A and its receptors were found to correlate with BMI and metabolic parameters in the human population, we investigated the potential role of Sema7A in obesity and hepatic steatosis. GWAS and GEPIA database was used to analyze SNPs in SEMA7A and the correlation of Sema7A expression with lipid metabolism related genes. Sema7A−/− mice and recombinant Sema7A (rSema7A) were used to study the role of Sema7A in HFD-induced obesity and hepatic steatosis. Adipose tissue-derived mesenchymal stem cells (ADSCs) were used to examine the role of Sema7A in adipogenesis, lipogenesis and downstream signaling. Deletion of Sema7A aggravated HFD-induced obesity. Sema7A deletion enhanced adipogenesis in both subcutaneous and visceral ADSCs, while the addition of rSema7A inhibited adipogenesis of ADSCs and lipogenesis of differentiated mature adipocytes. Sema7A inhibits adipo/lipogenesis potentially through its receptor integrin β1 and downstream FAK signaling. Importantly, administration of rSema7A had protective effects against diet-induced obesity in mice. In addition, deletion of Sema7A led to increased hepatic steatosis and insulin resistance in mice. Our findings reveal a novel inhibitory role of Sema7A in obesity and hepatic steatosis, providing a potential new therapeutic target for obesity and metabolic diseases. • Sema7A−/− mice are more sensitive to diet-induced obesity, hepatic steatosis and insulin resistance. • Sema7A inhibits adipo/lipogenesis and potentially protects against diet-induced obesity via the integrin β1/FAK axis. • Administration of recombinant Sema7A protects against diet-induced obesity in mice. [ABSTRACT FROM AUTHOR]

Summary: Among men, prostate cancer is the most common cancer diagnosed, and the second leading cause of death from cancer in the industrialized countries. In spite of substantial progress in research, diagnosis and treatment, the causes of prostate cancer remain largely unknown. In this paper, we propose the hypothesis that prostate cancer represents another entity in the constellation of disease incited by the greater sympathetic activity that develops with age. However, the specific mechanisms of changes of increased prostatic cell proliferation and carcinogenesis caused by the autonomic nervous system have not yet been clarified. In regard to this matter, future studies should outline a more complete mechanism. [Copyright &y& Elsevier]

Abstract: Sedimentary sequences occurring in desert dunes reflect changes in desert systems, and as such may contain signals useful for recognizing spatial and temporal changes of deserts and their response to regional or even global climate fluctuations. Geomorphological and palaeoenvironmental studies within the dune fields of the Asian middle-latitudes have provided some solid evidence for interpreting the history of these sand seas. Using the Hunshandake (Otindag) Sandy Land, a sandy area covered primarily by stabilized dunes and located in the semi-arid zone of eastern Inner Mongolia, China (Fig. 1), as an example, we studied the initiation and variation in the dune landscape in the eastern portion of the desert belt in northern China. On the basis of physical and biochemical indicators in the sediments and OSL chronology, we herein argue that this dune system in the middle latitudes of eastern Asia is much younger than previously assumed and that it has responded sensitively to climate change during the late Quaternary. Geological evidence from the Sandy Land suggests that most of the current dunes are of late Pleistocene or even Holocene age. Palaeosols intercalated in the aeolian sequences and their OSL chronology show that the climate of the Hunshandake was much wetter than today between 9.6 ka and 3 ka. This resulted in stabilization of the dunes in the eastern and central portions of the Sandy Land. Epochs of reworking or stabilization of the dunes are broadly consistent with the fluctuations in northern hemisphere solar radiation although with an obvious time lag. Because the increase rate of annual precipitation was not sufficient to fully stabilize the dunes in more arid part of the region, some active dunes persisted even during this long-lasting wetter epoch. We conclude that periods of Holocene dune stabilization due to palaeosol formation varied along the climate gradients across the various sandy lands of northern China, and in general it began earlier and lasted longer in the east than in the west. The general nature of the sandy lands and their counterparts in the western portion of the desert belt during the LGM and mid-Holocene climate optimum is discussed in comparison with their current states. [Copyright &y& Elsevier]

Abstract: Chemical weathering is an integral part of the earth surface processes, whose spatial patterns and controlling factors on continental scale are still not fully understood. Highlands of the Asian continent have been shown having some of the highest observed rates of chemical weathering yet reported. However, the paucity of river gauge data in many of these terrains has limited determination of chemical weathering budget in a continental scale. A dataset of three large watersheds throughout northern Xinjiang in Central Asia is used to empirically identify chemical weathering regimes and interpret the underlying controlling factors. Detailed analysis of major ion ratios and a forward model of mass budget procedure are presented to distinguish the relative significances and contributions of silicate, carbonate weathering and evaporite dissolution. The analytical results show that carbonic acid is the most important weathering agent to the studied watersheds. Silicate weathering contributes, on average, ∼17.8% (molar basis) of total cations on a basin wide scale with an order of Zhungarer>Erlqis>Yili, indicating that silicate weathering, however, does not seem to be intense in the study basins. Evaporite dissolution, carbonate weathering and precipitation input contribute 43.6%, 29.7% and 8.9% of the total dissolved cations on average for the whole catchment, respectively. The three main morphological and hydrological units are reflected in water chemistry. Rivers from the montane areas (recharge area) of the three watersheds are very dilute, dominated by carbonate and silicate weathering, whereas the rivers of piedmont areas as well as the rivers of the sedimentary platform (runoff area) are dominated by carbonate weathering, and rivers of desert plain in the central Zhungarer basin (discharge area) are dominated by evaporite dissolution and are SO4 rich. This spatial pattern indicates that, beside lithology, runoff conditions have significant role on the regional chemical weathering regimes. Chemical weathering processes in the areas appear to be significantly climate controlled, displaying a tight correlation with runoff and aridity. Carbonate weathering are mostly influenced by runoff, which is higher in the mountainous part of the studied basins. The identification of chemical weathering regimes from our study confirmed the weathering potential and complexity of temperate watersheds in arid environment and that additional studies of these terrains are warranted. However, because the dominant weathering reactions in the sedimentary platform of northern Xinjiang are of carbonates and evaporites rather than silicate minerals, and the climatic factors have important role on the rock weathering regimes, we think that weathering at the arid temperate drainage system (Central Asia) is maybe not an important long-term sink for atmospheric CO2, if the future climate has no great change. [Copyright &y& Elsevier]

We report a rare case of right retrocaval ureter and left nutcracker syndrome in a young man who was accurately diagnosis preoperatively with the help of intravenous urogram and gray-scale and color flow Doppler ultrasonography, and confirmed by computed tomography. Surgery that involves resection of the retrocaval segment and relocation of the anastomosis anterior to the inferior vena cave was performed for the right retrocaval ureter, whereas surveillance was adopted for the left nutcracker syndrome. [Copyright &y& Elsevier]

Abstract: This paper reviews our current understanding of Quaternary climate and landscape changes in the desert areas of northern China, a key portion of the middle-latitude drylands on Earth. Combining earlier studies with our recent research and experience, we offer a comprehensive picture of the state of Chinese deserts during the Quaternary and, in the interest of enhancing future research, identify knowledge gaps and areas of uncertainty. Lacustrine deposits found over an area ranging from China’s western Taklamakan Desert to the eastern Hunshandake Sandy Lands suggest that extensive lakes occurred in China’s deserts during the Pleistocene. Analysis of digital elevation models from SRTM (Shuttle Radar Topography Mission) data supports this interpretation and shows the significant extent of these former lakes. New estimates of mean annual evaporation of ca. 1000 mm from lake surfaces and ca. 100 mm from land surfaces, confirms that local and regional rainfall is critical for maintenance of desert lakes in this temperate zone, especially during intervals when the mean annual rainfall is more than 100 mm. Rapid shifts between sand seas and lakes in geologically and environmentally diverse settings suggest that the drylands of China are very sensitive ephemeral systems, and not long-lasting as previously thought. Available chronologies suggest that there were large lakes in the western Taklamakan Desert and the Chadamu Basin during MIS (Marine Isotope Stage) 3, at ∼30 ka, probably related to a period of strong influence of northern hemispheric westerly winds. Channels and elevation models revealed by SRTM data and remains of lacustrine sediments also indicate that there was a large lake in the Hunshandake Sandy Lands in the eastern portion of the desert belt during the Quaternary. There is significant evidence that during the middle Holocene strong summer monsoons led to a relatively large increase in moisture availability in the entire desert belt of northern China. Lacustrine records from the Badain Jaran Desert in western Inner Mongolia suggest that it was generally dry before 10 cal ka, becoming wetter from 10 to 4 cal ka, and dry again afterwards. Study of palaeosols widely occurring in dune stratigraphy in the eastern portion of the desert belt, suggests that there was a period of wet and warm climate in this region during the mid-Holocene Optimum, at a minimum between 6 ka and 4 ka, but possibly lasting longer. Recent observations dealing with the generation and transport of dust from Central Asia indicate that the causal relationship between sand seas and loess sequences is not as close as previously assumed. These results suggest that there is an urgent need to examine whether the frequency and amplitude of climatic variation in Chinese deserts are somehow similar to that having occurred in the Sahara Desert of North Africa. Deserts in northern China were also important focal regions for Neolithic cultures during intervals when environmental conditions supported a denser vegetative cover. There is evidence that some areas of woody vegetation to the west of Badain Jaran Desert were deforested by humans by ca. 4000 yr B P, although it is still debatable whether humans have had a significant impact in other areas at that time. Opinions on the severity of desertification vary and are sometimes contradictory due to the lack of long-term, field-based, investigations. [Copyright &y& Elsevier]

Abstract: In the arid region of northern Xinjiang, one of the least-studied areas in China, three watersheds, namely those of the Yili, Zhungarer and Erlqis, have become the focus of attention due to rapidly increasing human population and water demands. The hydrogeochemistry of natural water from the three watersheds was investigated. The ionic chemistry of natural waters from these watersheds changes considerably on a regional scale. The waters are neutral to alkaline in nature and most of them are soft-fresh waters. The total dissolved solid (TDS) varies over two orders of magnitude with a mean value of 580mg/L, about 1.2 times and 4.6 times those of the Huanghe (Yellow River) and the world spatial median, respectively, but only 40% and 0.8% of those of the Tarim and the western Alashan watersheds, respectively. Much of the solutes and physicochemical parameters in these waters are under the highest desirable limits of the World Health Organization (WHO) for drinking purpose and a plot of sodium adsorption ratio versus EC shows that most waters are of good water quality for irrigation. Water–rock interaction and saturation index (SI) for selected minerals are evaluated. The SI of these natural waters is out of equilibrium (undersaturated) with respect to major carbonates (calcite and dolomite) and evaporites (gypsum and halite). The high concentrations of alkali earth metals, alkalinity and the high (Ca+Mg)/(Na+K) and Na/Cl ratios indicate that the release of major solutes in these waters is controlled largely by dissolution processes of carbonate and partly by silicate weathering, while, cation exchange reactions, soil–salt leaching and evaporation processes also play an important role. The effects of local pollution are minimal in the montane and piedmont areas of these watersheds but are significant in the oases and central areas of the drainage basins. [Copyright &y& Elsevier]

Objectives: To report our experience in the diagnosis and surgical treatment of the nutcracker syndrome, which is uncommon, with few larger series published. Methods: We retrospectively analyzed 23 patients with the nutcracker syndrome who presented to our institution from July 1998 to July 2007. A diagnosis of the nutcracker syndrome was suspected from the clinical examination, ultrasound, computed tomography, and magnetic resonance imaging findings. The diagnosis was confirmed by determination of the renocaval gradient using phlebography of the left renal vein (LRV). Because of recurrent gross hematuria and persistent orthostatic proteinuria, 7 patients (4 females and 3 males) underwent LRV transposition. Other patients with mild and tolerable symptoms were treated conservatively. The follow-up range was 14-122 months (mean 42.6). Results: All 23 patients met the criteria for establishing the diagnosis of the nutcracker syndrome. Ultrasonography, computed tomography, and magnetic resonance imaging revealed entrapment of the LRV between the superior mesenteric artery and aorta. The renocaval pressure gradient was ≥4 mm Hg (normal <1 mm Hg) in all patients. The hematuria and proteinuria disappeared in the 7 patients who underwent LRV transposition, and only 1 patient continued to have pelvic pain. No complications occurred during surgery. The postoperative complications included paralytic ileus in 2 and retroperitoneal hematoma in 1 patient. No improvement or only partial improvement was observed in most patients receiving conservative treatment. Conclusions: The diagnosis of the nutcracker syndrome is determined from the clinical examination and radiographic findings. In patients who require surgical treatment, LRV transposition is an efficient surgical approach with an acceptable risk of complications. However, in some cases, pelvic pain may persist despite removal of the obstruction of the renal venous backflow. [Copyright &y& Elsevier]