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Background: The non-small cell variant of lung cancer (NSCLC) has a poorer prognosis. It is typically diagnosed through non-invasive imaging. Of particular note has been FDG-PET/CT, which has been investigated across various settings with differing results. Objective: This study to pool the available information on the diagnostic performance of 18-F FDG PET/CT for detecting NSCLC recurrence. Methods: A systematic literature search was conducted across electronic databases for studies published prior to May 2021. The QUADAS tool was applied to assess study quality, and ta meta-analysis was performed to retrieve pooled estimates. Chi squared tests and I2 statistics were used to assess heterogeneity. Egger’s test and funnel plots were used to assess publication bias. Results: Literature search yielded 20 studies featuring data on 1,973 patients. The majority of the studies had low bias risk. The pooled sensitivity and specificity were 96% (95% CI: 91%-98%) and 93% (95% CI: 89%-95%), respectively. The LRP and LRN estimates were in the left upper quadrant of the LR scattergram, indicating that F18-FDG PET/CT can be utilized for both confirmation and exclusion. The AUC was 0.98 (95% CI: 0.92-0.99). Fagan’s nomogram showed that F18-FDG PET/CT had good clinical utility for recurrent NSCLC diagnosis. There was considerable between-study variability (p=0.02). Funnel plot was asymmetrical, indicating the possibility of publication bias. Conclusion: This meta-analysis found FDG-PET/CT to be highly accurate for identifying NSCLC recurrence. However, more studies assessing this modality across different patient situations is required to strengthen the argument for changing international guidelines and practices.

Cryptorchidism-caused adult infertility is a common component of idiopathic reasons for male infertility. Retinoic acid (RA) has a vital effect on the spermatogenesis process. Here, we found that the expression of c-Kit, Stra8, and Sycp3 could be up-regulated via the activation of retinoic acid receptor α (RARα) after RA supplementation in neonatal cryptorchid infertile rats. We also demonstrated that the protein expression of PI3K, p-Akt/pan-Akt, and p-mTOR/mTOR was higher in cryptorchid than in normal testes, and could be suppressed with RA in vivo. After RA treatment in infertile cryptorchid testis in vivo, the levels of the autophagy proteins LC3 and Beclin1 increased and those of P62 decreased. Biotin tracer indicated that the permeability of blood-testis barrier (BTB) in cryptorchid rats decreased after RA administration. Additionally, after blocking the RARα with AR7 (an RARα antagonist) in testicle culture in vitro, we observed that compared with normal testes, the PI3K-Akt-mTOR signaling pathway and the autophagy pathway was increased and decreased, respectively, which were coincident with cryptorchisd testes in vivo. Additionally, the appropriate concentrations of RA treatment could depress the PI3K-Akt-mTOR signaling pathway and improve the autophagy pathway. The results confirmed that RA can rehabilitate BTB function and drive key protein levels in spermatogonial differentiation through depressing the PI3K-Akt-mTOR signaling pathway via RARα.

To weaken the noise pollution of wet cooling towers, a large-scale wet cooling tower with a 660 MW unit is used as an example, and the water-splashing noise is measured in a field test. The sound source characteristics are determined based on the field test results, and the sound source surface is specified as the initial parameters of the simulation. Then, the noise propagation model for the wet cooling tower is established based on the ray-tracing method, with a maximum relative error of only 2.22 %. Two noise reduction schemes, vertical and curved sound barriers, are proposed based on this model. Furthermore, the noise reduction effects of two different types of sound barriers are investigated. Under identical conditions, the simulation reveals that the vertical sound barrier performs better than the curved sound barrier in terms of noise reduction. In addition, The results also show that a vertical sound barrier with a length of 90 meters, a height of 10 meters, and a distance of 15 meters from the tower is an optimal scenario, with an A-weighted sound pressure level (A-SPL) of just 42.08 dB(A). In summary, the noise problem associated with wet cooling towers may be effectively addressed in this instance.

Biological self-assembly is crucial in the processes of development, tissue regeneration, and maturation of bioprinted tissue-engineered constructions. The cell aggregates—spheroids—have become widely used model objects in the study of this phenomenon. Existing approaches describe the fusion of cell aggregates by analogy with the coalescence of liquid droplets and ignore the complex structural properties of spheroids. Here, we analyzed the fusion process in connection with structure and mechanical properties of the spheroids from human somatic cells of different phenotypes: mesenchymal stem cells from the limbal eye stroma and epithelial cells from retinal pigment epithelium. A nanoindentation protocol was applied for the mechanical measurements. We found a discrepancy with the liquid drop fusion model: the fusion was faster for spheroids from epithelial cells with lower apparent surface tension than for mesenchymal spheroids with higher surface tension. This discrepancy might be caused by biophysical processes such as extracellular matrix remodeling in the case of mesenchymal spheroids and different modes of cell migration. The obtained results will contribute to the development of more realistic models for spheroid fusion that would further provide a helpful tool for constructing cell aggregates with required properties both for fundamental studies and tissue reparation.

Renal fibrosis occurs largely through epithelial–mesenchymal transition (EMT). This study explored the beneficial effects of a human umbilical cord mesenchymal stem cell-loaded decellularized kidney scaffold (ucMSC-DKS) on renal fibrosis in a rodent model of post-transplantation renal failure, and the underlying mechanism. Rat-derived DKSs were examined after preparation, and then recellularized with human ucMSCs to prepare cell-loaded patches. A rat model of renal failure was established after subtotal nephrectomy (STN). The cell patches were transplanted to remnant kidneys. Changes in renal function, histology, EMT, and proteins related to the transforming growth factor-β (TGF-β)/Smad signaling pathway in the remnant kidneys were examined 8 weeks after surgery, compared with non-cell patch controls. The DKSs were acellular and porous, with rich cytokine and major extracellular matrix components. The ucMSCs were distributed uniformly in the DKSs. Renal function was improved, renal fibrosis and EMT were reduced, and the TGF-β/Smad signaling pathway was inhibited compared with controls at 8 weeks after ucMSC-DKS patch transplantation. The ucMSC-DKS restores renal function and reduces fibrosis by reducing EMT via the TGF-β/Smad signaling pathway in rats that have undergone STN. It provides an alternative for renal fibrosis treatment.

Fillings are the core part of wet cooling towers, and generally speaking, the fillings are arranged in an equidistant pattern, which actually hampers the heat and mass transfer process. So the non-equidistant fillings which is the combination of large-spacing and small-spacing fillings are adopted to enhance the thermal performance. In this study, numerical simulation was conducted on one real wet cooling towers equipped for a 600 MW unit to study the relatively optimal combination of 26 mm and 30 mm spacing fillings (30 mm fillings are arranged in the inner zone and 26 mm fillings are stalled in the outer zone). The simulation results indicated that, compared with conventional equidistant fillings, the thermal and resistance performance improve partly under the non-equidistant fillings pattern. After adopting non-equidistant fillings, the aerodynamic field and the temperature field improve significantly. Furthermore, with the increase of the inner zone radius R1, the water temperature drop Δ t , cooling efficiency η and Merkel number N rise first and then decline, and the relatively optimal inner radius is 47.5 m in this case. When R1 = 47.5 m, compared with 26 mm equidistant fillings condition, Δ t , η, and N increase about 0.13 °C, 0.8%, and 0.03. And the ventilation rate G increases by about 751.32 kg/s at most. While the ambient air temperature changes, the non-equidistant fillings can also improve the cooling performance. Under the summer typical conditions, compared with all 26 mm and 30 mm equidistant fillings, the Δ t with the relatively optimal non-equidistant fillings rises by 0.17 °C and 0.2 °C, respectively.

Bacteria, especially gut bacteria play important roles in human health and diseases. The classification of many bacterial genera by the 16S ribosomal RNA (rRNA) has failed due to its low inter-species resolution. Given the wide distribution of riboswitches in bacteria, they may help 16S rRNA differentiate closely related species. We found that among 28 groups of species that could not be distinguished by 16S rRNA, eight of them could be separated by the TPP riboswitch and other riboswitches. Moreover, the species in the 16S rRNA database and these riboswitch databases overlap, therefore, using riboswitch databases can help 16S rRNA better identify species. In addition, we used Klenow DNA polymerase and a pair of short primers to facilitate the library construction of TPP riboswitches for sequencing. The sequencing results showed that the TPP riboswitch could detect the major phyla similar to those detected by 16S rRNA. Therefore, the TPP riboswitch and other riboswitch classes could potentially be applied to gut bacteria classification.

Cryptorchidism is a common disorder in children and may cause infertility in adults. The BTB is essential for maintaining the microenvironment necessary for normal spermatogenesis. This study investigated whether retinoic acid (RA) may regulate the proteins that are essential for integrity of the BTB in cryptorchidism. Female Sprague-Dawley rats were administrated flutamide during late pregnancy to induce a model of cryptorchidism in male offspring. The concentrations of RA and BTB tight and gap junction protein levels were significantly lower in untreated cryptorchid pups compared with normal pups, but almost normal in cryptorchid pups given RA. Studies in vitro corroborated these findings. The sperm quality of RA-treated model pups was better compared with the untreated model. RA treatment may have therapeutic potential to restore retinoic acid and proteins associated with integrity of the BTB in cryptorchid testis.

Stem cells present in urine possess regenerative capacity to repair kidney injury. However, the unique characteristics of urinary stem cells (USC) from patients with diabetic nephropathy (d-USC) are unknown. The goal of this study was to investigate stemness properties in cell phenotype and regenerative potential of d-USC, compared to USC from healthy individuals. Methods: Thirty-six urine samples collected from patients (n=12, age range 60-75 years) with diabetic nephropathy (stages 3-4 stage chronic kidney disease [CKD]) were compared with 30 urine samples from healthy age-matched donors (n=10, age range 60-74 years). Results: There were approximately six times as many cells in urine samples from patients with diabetic nephropathy, including twice as many USC clones as healthy donors. However, approximately 70% of d-USC had weaker regenerative capacity as assessed by cell proliferation, less secretion of paracrine factors, weaker telomerase activity, and lower renal tubular epithelial differentiation potential compared to healthy controls. In addition, the levels of inflammatory factors (IL-1β and Cx43) and apoptotic markers (Caspase-3, and TUNEL) were significantly increased in d-USC compared to USC (p

Contrast-enhanced multi-slice computed tomography (MSCT) is commonly used in the diagnosis of complex malignant tumours. This technology provides comprehensive and accurate information about tumour size and shape in relation to solid tumours and the affected adjacent organs and tissues. This case report demonstrates the benefit of using MSCT 3D imaging for preoperative planning in a patient with late-stage (T4) sarcomatoid renal cell carcinoma, a rare renal malignant tumour. The surgical margin on the liver was negative, and no metastases to veins, lungs or other organs were detected by abdominal and chest contrast-enhanced CT. Although sarcomatoid histology is considered to be a poor prognostic factor, the patient is alive and well 17 months after surgery. The MSCT imaging modality enables 3D rendering of an area of interest, which assists surgical decision-making in cases of advanced renal tumours. In this case, as a result of MSCT 3D reconstruction, the patient received justified surgical treatment without compromising oncological principles.

Renal fibrosis is a progressive pathological process that eventually leads to end-stage renal failure with limited therapeutic options. The aim of this study was to investigate the nephron-protective effect of human umbilical cord mesenchymal stem cells (ucMSCs) on renal fibrosis. UcMSCs were intravenously injected into renal fibrosis mice induced by aristolochic acid (AA) and co-cultured with HK-2 cells induced by TGF-β1, respectively. The kidney functions including serum creatinine (Scr) and blood urea nitrogen (BUN) levels, and histopathology were examined after treated with stem cells and normal saline as control. Immunohistochemical staining, immunofluorescent staining, and Western blot analysis were used to assessed the expression of proteins associated with epithelial to mesenchymal transition (EMT) and TGF-β/Smad signaling pathway. The results showed that ucMSCs effectively improved the kidney function and pathological structure, reduced AA-induced fibrosis and extracellular matrix deposition. Besides, UcMSCs significantly inhibited the EMT process and TGF-β1/Smad signaling pathway in AA-induced mice and TGF-β1-induced HK-2 cells compared to the control (p 0.05). Our data suggested that ucMSCs play as a nephron-protective role in anti-fibrosis through inhibiting the activation of TGF-β1/Smad signaling pathway.

Aim The growing number of patients suffering from chronic renal disease (CKD) is a challenge for the development of innovative therapies. Researchers have studied the therapeutic effects of cell therapy in acute kidney injury (AKI). However, the therapeutical effect of conditional medium (CM) in the CKD models have been rarely reported. Here, we examined the effects of umbilical cord derived-mesenchymal stem cells (hUC-MSCs) CM on renal fibrosis in a rat model of unilateral ureteral obstruction (UUO). Methods We randomly divided the animals into three groups: sham-operated, UUO, UUO + CM. CM was administered via the left renal artery after total ligation of the left ureter. Rats were killed after 14 days of obstruction. Histological changes and oxidative stress parameters were assessed. Western blotting and immunohistochemistry analysis were used to measure epithelial-mesenchymal transition (EMT) markers, including epithelial cadherin (E-cadherin), α-smooth muscle actin (α-SMA), tumor necrosis factor-α (TNF-α), Collagen-I, and transforming growth factor β1 (TGF-β1). Proliferation and apoptosis of renal tubular epithelial cells (RTEs) were also measured. Results HucMSC-CM significantly reduced the levels of malondialdehyde (MDA) and reactive oxygen species (ROS), and increased the activity of glutathione (GSH) induced by UUO. Moreover, CM significantly reduced the expression of TGF-β1, α-SMA, TNF-α and Collagen-I in UUO kidney, promoted the proliferation of RTEs and inhibited its apoptosis. In addition, the increased expression of E-cadherin also reflects the effective improvement of renal interstitial fibrosis. Conclusion This study shows that CM protects UUO-induced kidney damage and therefore could be a potential tool to prevent CKD progression.

To describe our clinical experience with nephron sparing surgery (NSS) for bilateral Wilms tumor and evaluate the outcomes of patients treated at one of the largest pediatric medical centers in China. Medical records of children with bilateral Wilms tumor undergoing NSS in the Children’s Hospital of Chongqing Medical University during a 15-year period were retrospectively analyzed. Data collected were composed of age at surgery, tumor response, tumor rupture during resection, final pathologic margins, use of radiation therapy, pathology reports, renal function, and patient survival. A total of 18 eligible patients (10 males, 8 females) with bilateral Wilms tumor at a mean age of 2.28 ± 1.12 years were identified. The administration of preoperative chemotherapy did not result in universally successful outcomes. All children underwent successfully unilateral or bilateral NSS, of which one had positive pathologic margins and five received radiation therapy postoperatively. The rates of tumor rupture and positive lymph nodes involvement were 11.1 and 19.4%, respectively. The pathological study showed favorable histology and unfavorable histology in 32 and 4 kidneys, respectively. The 4-year event-free survival and overall survival rates were 68.18 and 85.56%. In univariable analysis, tumor histology (p = 0.0028) and disease stage (p = 0.0303) appeared significantly associated with overall survival. After a median follow-up period of 41.5 months (range 10–89), three of the surviving patients were diagnosed with hypertension and one had renal insufficiency. Our experience suggests that NSS has become a feasible and effective option with good oncologic outcomes. Further research, ideally in a multicenter randomized manner, is warranted to better assess the role of NSS in this challenging clinical scenario.

The study was designed to quantify the thermal conditions in tall atria in office buildings to serve as a starting point towards understanding their performance. The simulation study of a non-segmented and segmented atrium of 250 m height reveals indoor air temperature, wind velocity contours and wind pressure coefficients at various heights of each atrium type. In a hot and humid climate like that of Singapore, the internal temperatures within each atrium stack remain constant at 27°C. However, the wind velocity in the non-segmented atrium (of 0.5 - 0.7 m/s) is lower than acceptable (0.9 m/s) for human occupancy. Adding segments and a larger inlet to the atrium solves the problem of low wind velocity without increasing the effective ambient temperature within the atrium stack. Additionally, the segmented atrium offers the advantage of displaying lower buoyancy forces by lowering the pressure differential within a tall stack thereby providing better comfort conditions.

To improve the heat and mass transfer performance of large wet cooling towers, a synergetic optimization method of non-equidistant fillings and non-uniform water distribution was proposed in this paper. The impact of the optimization scheme on the cooling performance was studied for the cooling tower equipped for a 600 MW unit. Firstly, the fillings were divided into two zones, and the optimized inner fillings radius was obtained according to the different non-equidistant fillings patterns, namely the optimized radius dividing point in the filings zone. Then, the cooling performance variation under different non-uniform water distribution patterns was discussed based on this optimized radius dividing point. The simulation results showed that the synergetic optimization coupling the fillings and water-spraying zones improves significantly the uniformity of the air dynamic and temperature field. The water temperature drops and ventilation rate all increase firstly and then decrease with the increase of the water distribution ratio in the inner zone. Compared with the equidistant fillings layouts of 26 mm and 30 mm, after the synergetic optimization, the outlet water temperature drops increase by 0.21 ℃, 0.22 ℃, and the ventilation rate enhances by 6.68%, 1.13% respectively in the design condition, but 0.28 ℃, 0.31℃ and 7.03%, 1.53% in the typical operating condition in summer. Additionally, the evaporation loss all decreases by about 3.3% in the design condition by comparison with the equidistant fillings layouts of 26 mm and 30 mm, but increases in the typical operating condition in summer.

Numerical simulation is an important means to study the thermal and resistance characteristics of natural draft wet cooling towers. The treatment method of droplet diameter distribution in the rain zone directly affects the accuracy of the numerical model, which becomes a key problem in the numerical simulation at present. In this paper, to provide an appropriate treatment method of droplet diameter, three kinds of droplet diameter distribution treatment models for the numerical simulation are studied and compared, including equivalent diameter method (EDM), Gaussian distribution method (GDM), and diameter distribution method based on field test (FTDM), and the influences of each treatment method on the simulation results are presented respectively, which provide references for the subsequent numerical simulation. It is found that each method can reasonably simulate the thermal characteristics of the cooling tower by determining their key parameters, but the temperature drop calculated by FTDM is the most accurate with a relative error of 0.58%. Additionally, FTDM can most accurately simulate the pressure drop with a relative error of 4.18% and the motion trajectory of the water droplets, so the FTDM should be given priority under the premise of known the droplet diameter distribution data of the tower.

Introduction Several urethroplasties have been employed in the surgical treatment of hypospadias. Neourethral strictures are among the most common postoperative complications that often require reoperation. Materials and Methods We created a hypospadias model in New Zealand white male rabbits through a hypospadias-like defect and acute repair. A total of 24 animals were randomly allocated into three groups: tubularized incised-plate urethroplasty (TIPU) group (8), perimeatal-based flap urethroplasty (Mathieu) group (8), onlay island flap urethroplasty (onlay) group (8), and corresponding surgical procedures were immediately performed to reconstruct neourethra. The rabbits were killed postoperatively at 5 days, 2 weeks, 6 weeks, and 3 months, respectively. The penile tissue was harvested for histological and biochemical investigations to evaluate the expressions of transforming growth factor β1 (TGF-β1) and α-smooth muscle actin (α-SMactin) in all groups. Results All rabbits were operated on uneventfully. The amount of collagen content was increased in the Mathieu and onlay groups than in the TIPU group (p Conclusion The neourethra repaired by TIPU was practically resumed to normal anatomy and scarring was less apparent than the two other groups. Therefore, TIPU is considered as a relatively rational approach for hypospadias repair. The activity of fibroblasts has been increased in the long term, which may be the pathogenesis of neourethral stricture following hypospadias repair.

OBJECTIVE: To investigate the transcriptome profile of genital tubercles (GTs) in male SD rats and explore the mechanism of hypospadias induced by Di (2-ethylhexyl) phthalate (DEHP). METHODS: Forty time-pregnant SD rats were randomly divided into 4 equal groups, namely GD16 group and GD19 group (in which the male GTs were collected on gestation day[GD]16 and GD19 for RNA-seq, respectively), control group and DEHP exposure group (with administration of oil and 750 mg/kg DEHP by gavage from GD12 to GD19, respectively).In the control and DEHP exposure groups, the GTs were collected from the male fetuses on GD19.5, and scanning electron microscopy and HE staining were used to observe the morphological changes.The differentially expressed genes (DEGs) in the GTs were screened using lllumina HiSeq 2000 followed by GO and KEGG enrichment analyses to characterize the transcriptome profile.Immunofluorescence assay was performed to verify the DEGs (Mafb) identified by RNA-seq results.Immunofluorescence assay and Western blotting were used to examine the expression levels of Mafb in the penile tissue. RESULTS: A total of 1360 DEGs were detected in the GTs between GD16 group and GD19 group by RNA-seq.Among these genes, 797 were up-regulated and 563 were down-regulated.These DEGs were mainly enriched in the cell adhesion plaque signaling pathway, axon guidance signaling pathway, and extracellular matrix receptor signaling pathway.Compared with that in GD16 group, Mafb was significantly up-regulated in GD19 group, which was consistent with the sequencing results.Mafb and β-catenin were significantly down-regulated in DEHP-exposed group compared with the control group (P < 0.01). CONCLUSION: Mafb expression increases progressively with the development of GTs in male SD rats.DEHP exposure causes significant down-regulation of Mafb and β-catenin, suggesting that β-catenin signaling pathway that affects Mafb is related to DEHP-induced hypospadias in SD rats.

Renal fibrosis occurs largely through epithelial-mesenchymal transition (EMT). This study explored the beneficial effects of a human umbilical cord mesenchymal stem cell-loaded decellularized kidney scaffold (ucMSC-DKS) on renal fibrosis in a rodent model of post-transplantation renal failure, and the underlying mechanism.Rat-derived DKSs were examined after preparation, and then recellularized with human ucMSCs to prepare cell-loaded patches. A rat model of renal failure was established after subtotal nephrectomy (STN). The cell patches were transplanted to remnant kidneys. Changes in renal function, histology, EMT, and proteins related to the transforming growth factor-β (TGF-β)/Smad signaling pathway in the remnant kidneys were examined 8 weeks after surgery, compared with non-cell patch controls.The DKSs were acellular and porous, with rich cytokine and major extracellular matrix components. The ucMSCs were distributed uniformly in the DKSs. Renal function was improved, renal fibrosis and EMT were reduced, and the TGF-β/Smad signaling pathway was inhibited compared with controls at 8 weeks after ucMSC-DKS patch transplantation.The ucMSC-DKS restores renal function and reduces fibrosis by reducing EMT via the TGF-β/Smad signaling pathway in rats that have undergone STN. It provides an alternative for renal fibrosis treatment.

Background It has been recognized that the incidence of prostatic utricle in boys is increasing and is closely associated with diseases such as hypospadias. However, the clinical features of prostatic utricle with normal external genitalia have received little attention. Methods Based on this, a series of 22 male children with prostatic utricles has been compiled by adding our 3 patients to 19 cases reported. All children enrolled had normal external genitalia. Clinical data of the case was reviewed. Results Urinary tract infection, purulent urethral discharge and pyuria were the most common presenting chief complaint (41%), irritative lower urinary tract symptoms were present in 17% of cases, obstructive lower urinary tract symptoms were noted in 14%. Urinary retention has been reported in 18% and epididymitis has been reported in 14%. Relatively rare clinical symptoms are abdominal pain, hematuria, and hematospermia. A case of calculus formation and a case of neoplasia within the prostatic utricle has been reported. A cystic mass found by digital rectal examination is the most common presenting sign. A utricular lesion posterior to the bladder was revealed by imaging examination. Unilateral renal agenesis was associated in 32% of reports. Non-surgical approach was chosen in 3 cases, transrectal ultrasonography guided aspiration has been reported in 1 case. Endoscopic techniques were used in 3 cases. Open excision was used in 11 cases. The laparoscopic excision was chosen in 3 cases and Robot-assisted laparoscopy was reported in 1 case. Symptoms and signs disappeared after treatment in all children, and no recurrence occurred during follow-up. Conclusions Prostate utricles without external genital anomalies are rarely reported in children, and are easily missed and misdiagnosed, often accompanied by recurrent urinary tract infections, lower urinary tract symptoms, epididymitis, dysuria and other symptoms. Imaging studies can confirm the diagnosis. Symptomatic and large utricles should be actively treated. The treatment program should be based on the age, clinical symptoms, and size and location of the utricle.

We explored the improved method to prepare decellularized kidney scaffold and provide experimental basis for kidney tissue engineering and renal pathology and toxicology in vitro research. We perfused rat kidneys with PBS (group control) and prepared the decellularized kidney scaffolds with sodium dodecyl sulfate (SDS) (group S), Triton X-100 combined with SDS (group TS), and Triton X-100 combined with SDS after repeated freezing and thawing (group FTS) in different flow velocity. Meanwhile we measured their fluid distributions and vascular resistance. We examined the degree of decellularization of acellular scaffolds by HE, DAPI staining and DNA quantification. We examined the retention of main composition and structural integrity of decellularized scaffolds by Masson, PAS and immunohistochemical staining. We also detected the ultrastructure, cytotoxicity and the level of growth factor of the scaffolds by scanning electron microscope, MTT and ELISA, respectively. The results showed that the time of decellularization in group FTS was less than that in group S and TS. The vascular resistance of scaffolds decellularized at 10 mL/min flow velocity was lower. The fluid distribution in groups S, TS and FTS was different from that in control group. No residual cell was detected by HE and DAPI staining. DNA content was less than 50 ng/mg. Masson, PAS and immunohistochemical staining results showed that there was extracellular collagen, polysaccharide, type I collagen, type IV collagen, fibronectin and laminin in the decellularized scaffolds, and the scanning electron microscope result showed the scaffolds had the honeycomb structure. The cytotoxicity level of decellularized scaffolds was between grade 0 to 1. The level of VEGF, EGF, IGF-1 and PDGF-BB in group FTS were significantly higher than those in group S and TS. In concluding, combining freeze-thawing with perfusion can produce more ideal and effective whole organ decellularized scaffold of rat kidney, and make a foundation for the study of kidney tissue engineering and in vitro pathology and toxicology of kidney.本研究旨在探索优化肾脏脱细胞支架的制备方法，为肾脏组织工程及肾脏体外病理、毒理研究提供实验基础。取大鼠肾脏灌注PBS 作为对照组 (Control 组)，在不同流速下分别以十二烷基磺酸钠 (Sodium dodecyl sulfate，SDS) 灌注 (S 组)，Triton X-100 联合SDS 灌注 (TS 组)，反复冻融后Triton X-100 联合SDS 灌注(FTS组)，制备肾脏脱细胞支架，并测定其流体分布及脉管阻力。HE 染色、DAPI 染色、DNA 定量检测脱细胞支架脱细胞程度，Masson 染色、PAS 染色、免疫组织化学染色检测脱细胞支架主要成分的保留和结构的完整，扫描电镜检测支架的超微结构，MTT 法检测支架的细胞毒性，ELISA 检测支架中生长因子的含量。结果显示，FTS 组脱细胞用时较S 组、TS 组少，10 mL/min 组支架脉管阻力较低，S 组、TS 组、FTS 组流体分布与Control 组存在差异。HE 染色和DAPI 染色显示各组支架未见细胞成分残留，DNA 含量＜50 ng/mg。Masson 染色和PAS 染色可见细胞外网状胶原及多糖，免疫组织化学染色见Ⅰ型胶原 (CollagenⅠ)、Ⅳ型胶原蛋白 (Collagen Ⅳ)、纤维连接蛋白 (Fibronectin)、层粘连蛋白 (Laminin) 表达。扫描电镜见支架呈蜂窝状结构。MTT 法检测支架细胞毒性分级在0–1 级之间。ELISA 检测提示FTS 组VEGF、EGF、IGF-1、PDGF 含量明显高于S组和TS组。综上，联合冻融和灌注法能够制备更为理想且有效的大鼠肾脏整器官脱细胞支架，为肾脏组织工程及肾脏体外病理、毒理学研究奠定基础。.

Air pollutants existing in the environment may have negative impacts on human health depending on their toxicity and concentrations. Remote sensing data enable researchers to map concentrations of various air pollutants over vast areas. By combining ground-level concentrations with population data, the spatial distribution of health impacts attributed to air pollutants can be acquired. This study took five highly populated and severely polluted provinces along the Huaihe River, China, as the research area. The ground-level concentrations of four major air pollutants including nitrogen dioxide (NO2), sulfate dioxide (SO2), particulate matters with diameter equal or less than 10 (PM10) or 2.5 micron (PM2.5) were estimated based on relevant remote sensing data using the geographically weighted regression (GWR) model. The health impacts of these pollutants were then assessed with the aid of co-located gridded population data. The results show that the annual average concentrations of ground-level NO2, SO2, PM10, and PM2.5 in 2016 were 31 &micro, g/m3, 26 &micro, g/m3, 100 &micro, g/m3, and 59 &micro, g/m3, respectively. In terms of the health impacts attributable to NO2, SO2, PM10, and PM2.5, there were 546, 1788, 10,595, and 8364 respiratory deaths, and 1221, 9666, 46,954, and 39,524 cardiovascular deaths, respectively. Northern Henan, west-central Shandong, southern Jiangsu, and Wuhan City in Hubei are prone to large health risks. Meanwhile, air pollutants have an overall greater impact on cardiovascular disease than respiratory disease, which is primarily attributable to the inhalable particle matters. Our findings provide a good reference to local decision makers for the implementation of further emission control strategies and possible health impacts assessment.

Background Autologous urothelial cells are often obtained via bladder biopsy to generate the bio-engineered urethra or bladder, while urine-derived stem cells (USC) can be obtained by a non-invasive approach. The objective of this study is to develop an optimal strategy for urothelium with permeability barrier properties using human USC which could be used for tissue repair in the urinary tract system. Methods USC were harvested from six healthy adult individuals. To optimize urothelial differentiation, five different differentiation methods were studied. The induced cells were assessed for gene and protein expression markers of urothelial cells via RT-PCR, Western blotting, and immunofluorescent staining. Barrier function and ultrastructure of the tight junction were assessed with permeability assays and transmission electron microscopy (TEM). Induced cells were both cultured on trans-well membranes and small intestinal submucosa, then investigated under histology analysis. Results Differentiated USC expressed significantly higher levels of urothelial-specific transcripts and proteins (Uroplakin III and Ia), epithelial cell markers (CK20 and AE1/AE3), and tight junction markers (ZO-1, ZO-2, E-cadherin, and Cingulin) in a time-dependent manner, compared to non-induced USC. In vitro assays using fluorescent dye demonstrated a significant reduction in permeability of differentiated USC. In addition, transmission electron microscopy confirmed appropriate ultrastructure of urothelium differentiated from USC, including tight junction formation between neighboring cells, which was similar to positive controls. Furthermore, multilayered urothelial tissues formed 2 weeks after USC were differentiated on intestine submucosal matrix. Conclusion The present study illustrates an optimal strategy for the generation of differentiated urothelium from stem cells isolated from the urine. The induced urothelium is phenotypically and functionally like native urothelium and has proposed uses in in vivo urological tissue repair or in vitro urethra or bladder modeling. Electronic supplementary material The online version of this article (10.1186/s13287-018-1035-6) contains supplementary material, which is available to authorized users.