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Interbedded sandstones, shales, and coal seams were formed in marine-continental transitional environments of coal measures, and the gas source of its tight sand gas has been uncertain, which hinders the progress of natural gas exploration. This article uses the Longtan tight sand gas in west Guizhou as an example to investigate the reservoir features, gas charging history, and main source rock of tight sand gas by examining thin sections, scanning electron microscopy images, X-ray diffraction results, and the fluid inclusions with burial and thermal histories and noble gas analysis. The Longtan sandstones in this study are classified as litharenites which are characterized by low compositional and textural maturities, and high clay contents, and are distinguished petrographically from conventional sandstones by the extensive existence of micropores and microfractures. The results of the homogenization temperatures of the fluid inclusions show that the Longtan tight sand gas is a single-stage accumulation which occurred during the Late Triassic. Furthermore, through the analysis of the helium and argon isotopes of noble gases, a calculation model was established for determining the shale and coal contributions to the tight sand gas. The research results show that the Longtan tight sand gas mainly belongs to the crust-derived gas, mostly from the Longtan shale-derived contribution and to a lesser extent from the Longtan coal-derived contribution. The measured 40Ar/36Ar values of the Longtan shales and coals are consistent with the forecasted 40Ar/36Ar values from the calculation model, demonstrating that the model is viable to calculate the source rock contribution to the tight sand gas. Therefore, the Longtan shales as main source rocks can generate hydrocarbons to charge neighboring tight sandstones to form tight gas accumulation in the Longtan Formation, which provides an opportunity for tight gas development in west Guizhou.

Introduction: We have developed a modified vasoepididymostomy procedure, namely "fenestrated" transversal two-suture microsurgical intussusception vasoepididymostomy. This study aimed to investigate the therapeutic efficacy and outcome of this fenestrated vasoepididymostomy for epididymal obstructive azoospermia. Methods: Microsurgical two-suture transversal intussusception vasoepididymostomy was performed using our modified fenestration technique in 64 obstructive azoospermia (OA) patients due to epididymal obstruction at our hospital. Fenestration means making an opening on the epididymal tubule wall. The edges of the epididymal tubule "window" were stitched transversally (2 stitches) using the two double-armed 9-0 atraumatic suture. The epididymal tubule was anastomosed to the lumen of the vas deferens. The patency rate and pregnancy rate were assessed. Results: Of the 64 OA patients, 45 received bilateral microsurgical two-suture transversal intussusception vasoepididymostomy while 19 underwent unilateral microsurgical two-suture transversal intussusception vasoepididymostomy. All of the patients were followed up after the operation. The follow-up period ranged from 4 to 54 months. Among 45 cases of bilateral surgery, the patency rate was 88.89% (40/45), and the natural pregnancy rate was 28.89% (13/45). After the patency was confirmed postoperatively, 3 cases had recurrent OA, of which 2 cases had return of sperm to the ejaculate by oral antibiotics and scrotal self-massage. As for the 19 cases of unilateral microsurgery, the patency rate was 68.42% (13/19), and the natural pregnancy rate was 21.05% (4/19). Conclusion: The fenestrated transversal two-suture microsurgical intussusception vasoepididymostomy can achieve a good patency rate in OA patients, and did not increase the difficulty and duration of the procedure.

Computed tomography urography imaging is routinely performed to evaluate the kidneys. Kidney 3D segmentation and reconstruction from urographic images provides physicians with an intuitive visualization way to accurately diagnose and treat kidney diseases, particularly used in surgical planning and outcome analysis before and after kidney surgery. While 3D fully convolution networks have achieved a big success in medical image segmentation, they get trapped in clinical unseen data and cannot be adapted in deferent modalities with one training procedure. This study proposes an unsupervised domain adaptation or translation method with 2D networks to deeply learn urographic images for accurate kidney segmentation. We tested our proposed method on clinical urography data. The experimental results demonstrate our proposed method can resolve the domain shift problem of kidney segmentation and achieve the comparable or better results than supervised learning based segmentation methods.

Kidney segmentation is fundamental for accurate diagnosis and treatment of kidney diseases. Computed tomography urography imaging is commonly used for radiologic diagnosis of patients with urologic disease. Recently, 2D and 3D fully convolutional networks are widely employed for medical image segmentation. However, most 2D fully convolutional networks do not take inter-slice spatial information into consideration, resulting in incomplete and inaccurate segmentation of targets in 3D volumes. While the spatial information is truly important for 3D volumes segmentation. To tackle these problems, we propose a computed tomography urography kidney segmentation method on the basis of spatiotemporal fully convolutional networks that employ the convolutional long short-term memory network to model inter-slice features of computed tomography urography images. We trained and tested our proposed method on kidney computed tomography urography data. The experimental results demonstrate our proposed method can effectively leverage the inter-slice spatial information to achieve better (or comparable) results than current 2D and 3D fully convolutional networks.

Abdominal kidney segmentation plays an essential role in diagnosis and treatment of kidney diseases, particularly in surgical planning and clinical outcome analysis before and after kidney surgery. It still remains challenging to precisely segment the kidneys from CT images. Current segmentation approaches still suffer from CT image noises and variations caused by different CT scans, kidney location discrepancy, pathological morphological diversity among patients, and partial volume artifacts. This paper proposes a fully automatic kidney segmentation method that employs a volumetric convolution driven cascaded V-Net architecture and false positive reduction to precisely extract the kidney regions. We evaluate our method on publicly available kidney CT data. The experimental results demonstrate that our proposed method is a promising method for accurate kidney segmentation, providing a dice coefficient of 0.95 better than other approaches as well less computational time.

MicroRNAs (miRNAs) are endogenous non-coding RNAs that negatively regulate the expression of downstream targeted mRNAs. Increasing evidence has suggested that miRNAs act as tumor suppressors or oncogenes to interfere the progression of cancers. Here, we showed that miR-204-3p was decreased in bladder cancer tissues and cell lines. Down-regulation of miR-204-3p was significantly associated with a poor prognosis in bladder cancer patients. Overexpression of miR-204-3p inhibited proliferation and induced apoptosis in bladder cancer cells. Furthermore, miR-204-3p was found to bind to the 3'-untranslated region (UTR) of the lactate dehydrogenase (LDHA), which consequently reduced the expression of both mRNA and protein of LDHA. Interestingly, overexpression of miR-204-3p decreased glucose consumption and lactate production of bladder cancer cells. Overexpression of LDHA relieved the growth inhibition and cell apoptosis enhancement by miR-204-3p in bladder cancer cells. These results demonstrated that miR-204-3p negatively modulated the proliferation of bladder cancer cells via targeting LDHA-mediated glycolysis. MiR-204-3p might be a promising candidate for designing anticancer medication.

As an important type of (non-structural) fracture, diagenetic shrinkage fractures of shale play an important role in the storage, seepage, and, in particular, the fracturing production of shale oil and gas. However, there are few studies on this type of fracture. Based on the similarities between desiccation cracks in clayed soil and diagenetic shrinkage macro-fractures in shale (DSMFS), we performed an analogous study on the influence of four factors on DSMFS via experiments using shale core powder. The studies showed that the greater the thickness, the later the time of fracture initiation (TFI) and the higher the critical water content (CWC) of fracture initiation. Additionally, the greater the average fracture length, width, and fracture ratio, the lower the surface density of the fractures. Samples with different water salinities have similar TFIs and CWCs. As water salinity increases, the width, length, and fracture ratio of the DSMFS tend to slightly decrease, and surface density marginally increases. The high content of clay minerals exerts a tremendous influence on the DSMFS. Higher clay minerals result in later TFI and a higher CWC; the fracture length and fracture ratio increase, and in particular, the width increases sharply, whereas the surface density decreases. The influence degrees of each clay mineral are montmorillonite, chlorite, kaolinite, and illite from big to small. With a higher temperature, the TFI, length, width, and fracture ratio decrease; however, the CWC and surface density increase. Therefore, we observed the largest influence of clay mineral content and composition on the DSMFS, followed by the effect of thickness and temperature, whereas water salinity influenced the DSMFS the least. The DSMFS generally has four developmental stages: formation of the main fractures, formation of the sub-fractures, a stabilization, and a fixed stage.

To investigate the feasibility of preparing the porous extracellular matrix (ECM) by use of some chemicals and enzymes to decellularize the porcine carotid artery.The porcine carotid artery was procured, and warm ischemia time was less than 30 minutes. The porcine carotid artery was decellularized with 1% sodium dodecyl sulfate (SDS) for 60 hours to prepare common ECM; then common ECM was treated with 0.25% trypsin (for 6 hours) and 0.3 U/mL collagenase (for 24 hours) to prepare porous ECM. The common ECM and porous ECM were stained with HE, Masson's trichrome, and Orcein to evaluate the histological features. Then the mechanical property, cytotoxicity, and pore size of ECMs were determined. After 4 weeks of subcutaneous implantation in dogs, the histological examination was used for the study.Histological observation confirmed that 2 kinds of ECMs were decellularized completely and more porous structure was observed in porous ECM. Scanning electron microscope showed the pores in porous ECM were greater and the length of shorter axis in porous ECM ranged from 5 to 30 microm, the length of longer axis from 40 to 100 microm. The porosity of porous ECM (99.25%) was greater than that of common ECM (91.50%). The burst pressure of porous ECM decreased when compared with common ECM, showing significant difference [(0.154 3 +/- 0.0127) MPa vs. [0.305 2 +/- 0.015 7) MPa, P0.05]. There was no significant difference in suture retention strength between 2 kinds of ECMs (P0.05). The cytotoxicity test showed no obvious cytotoxicity in 2 kinds of ECMs. In vivo implantation test showed that the deeper host cells infiltration and more neo-microvessels in porous ECM were observed than in common ECM.SDS and some enzymes can be used to prepare porous ECM as the scaffold for tissue engineered blood vessels.