Staged transverse preputial island flap urethroplasty for proximal hypospadias: a single-center experience.

PURPOSE: To evaluate the intermediate outcomes of our institution's experience with staged TPIF urethroplasty for proximal hypospadias repair. METHODS: We retrospectively evaluated the medical records of patients who underwent repair of proximal hypospadias using staged TPIF urethroplasty at our hospital from 2011 to 2017. RESULTS: One hundred and two patients were included in the present study. The mean follow-up was 52.4 months (range 13-74 months). The mean age at the time of the first surgery was 13.5 months (range 11-65 months). There were two main types of initial complications including meatal stenosis in four (3.9%) and urethrocutaneous fistula in three (2.9%) patients after the first stage. Surgical complications were seen in 15 patients after second stage, including urethrocutaneous fistulas in 8 (7.8%), urethral strictures in 5 (4.9%), urethral diverticula in 2 (1.9%). Overall complication rates after second stage were 14.7%. The incidence of fistulas was lower in patients who underwent repair with a tunica vaginalis flap (1/29, 3.4%) than with the dartos fascia (7/73, 9.6%; p = 0.435). CONCLUSIONS: Our results show that staged TPIF urethroplasty is a viable and durable technique for primary severe proximal hypospadias. This procedure was associated with a 14.7% complication rate in the present study. Staged TPIF urethroplasty can reduce the incidence of urethral strictures and diverticula associated with the second stage.

[Effects of different zinc nutritional status on iron metabolism in rats].

OBJECTIVE: To study the effects of different zinc nutritional status on iron metabolism and explore the potential role of iron regulator protein 2 (IRP2) under conditions of zinc deficiency. METHODS: Forty clean male SD rats were randomly divided into four groups according to the weight and every group included 10 rats. The rats were administrated normal iron and zinc control group (ZA group), normal iron and slight deficient group (ZD group), Paired fed group (PF group), normal iron and zinc excessive group (ZE group). Rats were sacrificed by sodium pentobarbital anesthesia after 8 weeks and serum, liver and spleen of the rats were collected. The serum zinc, serum iron, hemoglobin, serum transferrin receptor, serum ferritin, iron and zinc in the liver, iron and zinc in the spleen were determined. The level of IRP2 mRNA expression,liver transferring receptor (TfR) mRNA expression and ferritin (Fn) mRNA expression were measured using reverse transcription polymerase chain reaction (RT-PCR) method. RESULTS: Compared with that of the control group, iron content both in the liver and spleen, and the concentration of serum iron in ZE group was significantly decreased (P < 0.05). Compared with the control group, zinc deficiency increased iron content in the liver and the concentration of serum transferrin receptor significantly (P < 0.05), while the concentration of serum iron was significantly decreased (P < 0.05). Compared with the control group, zinc deficiency increased the level of IRP2 mRNA and TfR mRNA expression in the liver significantly (P < 0.05). CONCLUSION: Zinc may affect iron nutritional status by influencing absorption, storage and transportation of iron. Zinc deficiency influences iron homeostasis in cells through affecting the expression of IRP2 and the activity of IRP-RNA combination and then change the expressions of ferritin and transferrin mRNA.

[Effects of copper deficiency on iron metabolism in rats].

OBJECTIVE: To study the effects of copper deficiency on iron metabolism, the expression of IRP mRNA and Fn mRNA and transferrin receptor mRNA in rats. METHODS: Forty clean male SD rats were randomly divided into four groups according to body weight and there were 10 rats in each group. The groups are normal iron and copper control group (group I), copper deficiency group (group II), normal iron and copper slightly deficient group (group III), both iron and copper slightly deficient group (group IV). After 8 weeks, all the rats were killed by sodium pentobarbital anesthesia and all samples were collected and detected for gene expression. RESULTS: Compared with the controls, the contents of serum iron and serum ferritin in completely copper deficiency group decreased (P < 0.05), but the level of serum transferrin receptor increased significantly under the complete copper deficiency (P < 0.05). Compared with that of the control group, the level of IRP2 mRNA in complete copper deficiency group was significantly increased (P < 0.05), and the level of transferrin receptor mRNA was also increased compared with that of the control group,compared with the control group the level of ferrintin RNA in complete copper deficiency group was significantly decreased (P < 0.05). CONCLUSION: The nutritional status of the iron may be affected by copper deficiency through influencing the absorption, the results indicate that copper deficiency influences iron homeostasis in cells through affecting the expression of IRP2 and the activity of IRP-RNA combination which change the expressions of ferritin and transferrin mRNA.

Nitrous oxide reductase gene (nosZ) and N2O reduction along the littoral gradient of a eutrophic freshwater lake.

Lake littoral zones are characterized by heterogeneity in the biogeochemistry of nutrient elements. This study aimed to explore the relationship between the nitrous oxide reductase gene (nosZ)-encoding denitrifier community composition/abundance and N2O reduction. Five samples (deep sediment, near-transition sediment, transition site, near-transition land and land soil) were collected along a littoral gradient of eutrophic Baiyangdian Lake, North China. To investigate the relationship between the nosZ-encoding denitrifier community structure and N2O reduction, the nosZ-encoding denitrifier community composition/abundance, potential denitrification rate (DNR) and potential N2O production rate (pN2O) were investigated using molecular biological technologies and laboratory incubation experiments. The results showed that the average DNR of sediments was about 25 times higher than that of land soils, reaching 282.5 nmol N/(g dry weight (dw) x hr) and that the average pN2O of sediments was about 3.5 times higher than that of land soils, reaching 15.7 nmol N/(g dw x hr). In the land area, the nosZ gene abundance showed a negative correlation with the N2O/(N2O + N2) ratio, indicating that nosZ gene abundance dominated N2O reduction both in the surface soils of the land area and in the soil core of the transition site. Phylogenetic analysis showed that all the nosZ sequences recovered from sediment clustered closely with the isolates Azospirillum largimobile and Azospirillum irakense affiliated to Rhodospirillaceae in alpha-Proteobacteria, while about 92.3% (12/13) of the nosZ sequences recovered from land soil affiliated to Rhizobiaceae and Bradyrhizobiaceae in alpha-Proteobacteria. The community composition of nosZ gene-encoding denitrifiers appeared to be coupled with N2O reduction along the littoral gradient.

Insights into the peroxomonosulfate activation on boron-doped carbon nanotubes: Performance and mechanisms.

Preparation of carbonaceous catalysts by doping with boron (B) is one of the most promising strategies for substitution of toxic transition metal catalysts in advanced oxidation processes. This study was dedicated to reveal the intrinsic structure-performance relationship of peroxomonosulfate (PMS) activation by B-doped carbon nanotubes toward catalytic oxidation of pollutants. Performance tests showed the catalyst realized more than 95% phenol removal at pH 7 in 1 h and 69.4% total organic carbon removal. The catalysts were characterized using scanning electron microscopy (SEM), transmission electron microscope (TEM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and electron paramagnetic resonance (EPR). Characterization results indicated that the topography of carbon nanotube was not significantly changed after B doped, while the defect sites increased from 1.05 to 1.23. The newly formed active sites may be presented in the form of C3B, CBO2 and CBO3, and reactive oxygen species (ROS) including OH, SO4-•, O2-• and 1O2 might be generated after activation by the active sites. Furthermore, B-MWNT-PMS∗ was also be detected by In-situ Raman, confirming the non-radical pathway and electron transfer mechanism. Beside of phenol, the reaction system of B-MWNT/PMS also can remove methylene blue, bisphenol S and diuron at pH = 7, confirming the universality and promising of this advanced oxidation technology.

Effective defect generation and dual reaction pathways for phenol degradation on boron-doped carbon nanotubes.

A new type of metal-free catalyst was successfully prepared by doping boron (B) in the carbon nanotube. The catalyst had 99.4% removal of phenol in 60 min at pH 7 by activating peroxymonosulfate (PMS). In order to explore the origin of the high catalytic activity, the samples were characterized by Raman and electron paramagnetic resonance (EPR), and the reactive oxygen species (ROS) in the process of catalytic degradation were investigated. The Raman results showed that the defect sites increased after doping, which indicated that the B doping increases the active sites on the surface of the carbon nanotubes. Identification experiments of ROS found that not only hydroxyl radicals (·OH) and sulfate radical (SO4-∙), but also singlet oxygen (1O2) exist in the system. The presence of multiple free radicals indicated the existence of free radical reaction pathway, and the presence of 1O2 confirmed the existence of non-radical reaction pathway. These results indicated that there were dual reaction pathways for the activation of persulfate by B-doped carbon nanotubes, which was the intrinsic nature for the high catalytic activity of the system.

[Effect of copper deficiency on iron metabolism in rats].

OBJECTIVE: To study the effect of copper deficiency on the nutritional status of iron, the expression of hepcidin mRNA and transferrin receptor mRNA in rats. METHODS: Forty eight clean male SD rats were randomly divided into four groups according to body weight; and there were 12 rats in each group. The groups are normal iron and copper control group (group I), normal iron and copper deficiency group (group II), normal iron and copper slightly deficient group (group III), both iron and copper slightly deficient group (group IV). Serum, liver and spleen of rats were collected by the end of 8th week. Serum copper, serum iron, hemoglobin, serum transferrin receptor, serum ferritin, liver iron and liver copper, spleen iron and spleen copper were determined. The expression of liver transferring receptor mRNA and hepcidin mRNA were measured by reverse transcription polymerase chain reaction (RT-PCR) method. RESULTS: Compared with the controls, the contents of serum iron and serum ferritin decreased (P < 0.05), but the level of serum transferrin receptor and the content of iron in liver and spleen increased significantly under copper deficiency. The expression of transferrin receptor mRNA in liver increased but the expression of hepcidin mRNA in liver decreased significantly under copper deficiency (P < 0.05). CONCLUSION: The nutritional status of iron may be affected by copper deficiency through influencing the absorption, storage and transportation of iron. Under the condition of copper deficiency, the expression of hepcidin mRNA in liver was lowered and the expression of transferrin receptor mRNA was enhanced through the way of iron response element-iron regulatory protein (IRE-IRP) to regulate iron metabolism.

Recurrent Ventral Curvature with Long-Term Follow-up after Transverse Preputial Island Urethroplasty.

OBJECTIVE: This study was aimed to assess the long-term outcomes of recurrent ventral curvature (VC) repaired in early childhood after transverse preputial island flap urethroplasty. MATERIALS AND METHODS: A total of 378 patients underwent transverse preputial island flap urethroplasty between January 2000 and January 2005 at our hospital. Of these patients, 43 were invited for assessment of VC after puberty. The age at surgery, types of hypospadias, degrees of recurrent VC, and surgical procedures were analyzed. RESULTS: The study included 43 patients with a mean age of 15.9 years (range, 12.3-17.9). The average age at the time of primary surgery was 1.9 years (range, 1.2-3.6). Of 43 patients, recurrent VC was identified in 14 (32.5%). In total, 8 out of 16 patients (50.0%) were successfully treated by urethral plate transection with skin release during the primary surgery, and 6 out of 27 patients (28.6%) underwent additional dorsal plication (DP; p = 0.093). Severe recurrent VC was observed in four, moderate curvature was observed in four, and mild curvature was observed in six cases. Recurrent VC was present more often in patients with complications (34.6 vs. 24.1%, p = 0.331), especially in severe urethral strictures that required open surgical reconstruction (p = 0.039). CONCLUSION: Although the patients in our study represent only a small portion of the overall hypospadias population, it is notable that 32.5% of these patients showed recurrent VC, including 28.6% of patients with transection plus DP. We suggest long-term follow-up of hypospadias at least during adolescence or even into adulthood.

[Effect of iron deficiency on vitamin A metabolism in rats].

OBJECTIVE: To study the effect of iron deficiency on vitamin A (VA) metabolism in rats. METHODS: Forty-four male SD rats were divided randomly into four groups according to their body weights and every group included 11 rats: control group (I group), entire iron deficient and normal VA group (II group), slight iron deficient and normal VA group (III group), slight iron and VA deficient (IV group). After being raised for 10 weeks, the rats were sacrificed and the serum VA, retinol-binding protein (RBP), hemoglobin, serum iron, serum iron saturation, VA in the liver, retinyl ester in the liver were determined. RESULTS: Iron deficiency decreased serum VA and VA in the liver significantly, and increased molar ratio of hepatic retinyl esters to retinol significantly. VA deficiency decreased the level of RBP mRNA expression in the liver significantly. CONCLUSION: Iron deficiency could affect VA nutritional status by influencing absorption, storage and transportation of VA.

[Effect of all-trans retinoic acid deficiency on iron metabolism in rat primary hepatocyte].

OBJECTIVE: To study the influence of atRA on iron metabolism in cultured primary rat hepatocyte. METHODS: Rat primary hepatocytes were isolated by two-step in situ collagenase perfusion method by Seglen, and after that Cell viability was observed by 0.4% trypan blue. And then primary hepatocyte were treated into 6 wells plate with 0, 0.5, 1 and 50 micromol/L atRA and DMEM contained 10% fetal bovine serum. After 72h, IRP2 mRNA, TFR mRNA, Fnm RNA levels were measured by RT-PCR. RESULTS: VA deficiency can decrease the viability and function. Moreover hepatic IRP2 mRNA and TFRmRNA levels were increased by VA deficiency, which diminishing expression of Fn mRNA. CONCLUSION: vitamin A deficiency can change cellular iron metabolism by inducing IRP2-Fn-TFR pathway. AtRA supplementation inhibited the increase in IRP2 mRNA expression. Taken together, these results indicate that vitamin A deficiency can regulate iron metabolism by IRP2-TFR-Fn pathway.

Complications of proximal hypospadias repair with transverse preputial island flap urethroplasty: a 15-year experience with long-term follow-up.

There is still debate regarding the optimal surgical approach for proximal hypospadias. This retrospective study aims to evaluate the long-term outcomes using transverse preputial island flap urethroplasty. A total of 320 patients were included, with a mean follow-up of 40.2 months (range: 1-156 months). Complications were encountered in 125 patients (39.1%), including fistulas in 53 (16.6%), urethral strictures in 31 (9.7%), and diverticula in 41 (12.8%). The mean timing of presentation with a complication was 15.8 months (median: 1.7, range: 1-145), of which 79.2% were early complications and 20.8% were late complications. In all, 20.8% of the patients with complications presented after ≥1 year, and 12.8% presented after ≥5 years. Univariate analysis revealed that age at the time of surgery, flap length, and location of the urethral meatus were not correlated with complications. A stricture was present in 31.7% (13/41) of those with diverticula (P < 0.001), while late urethral diverticula were accompanied by urethral strictures in 11.1% (1/9) of cases (P = 0.213). These results indicate that transverse preputial island flap urethroplasty still has a high incidence of complications, even when performed by highly experienced physicians. Most complications of hypospadias are diagnosed within 1 year postoperatively, while fistulas and urinary strictures generally occur within 2 months and diverticula tend to be present by 1 year.

[Effect of higher iron in diet on iron levels and hepcidin mRNA expression levels in rats].

OBJECTIVE: To study the effects of higher iron in diet on weight, iron status and hepcidin mRNA expression level in rats. METHODS: Sixty clean male SD rats were randomly divided into 6 groups according to the weight and were administrated higher iron at the doses of 35, 100, 200, 500, 1000, 3500 mg/kg of irons, respectively. Rats were killed after 8 weeks and serum and liver and duodenum of rats were collected. The serum iron levels, transferrin saturation were measured by colorimetric method. The serum ferrtin concentrations were measured by ELISA. The hepcidin mRNA level in liver and ferroportin mRNA expression in duodenum were measured by RT-PCR. RESULTS: After 8 week treatments, there was significant difference of the weights among the six groups. With the increases of iron levels in diet, the levels of serum iron, serum ferretin, and transferrin saturation were gradually increased, and the hepcidin mRNA expression level in liver significantly increased, and the expression of ferroprotin mRNA expression level in duodenum was decreased. CONCLUSION: Higher iron diet could influence the weights, serum iron status, liver hepcidin and duodenum ferroportin mRNA expression levels of the rats.

Ubiquitous anaerobic ammonium oxidation in inland waters of China: an overlooked nitrous oxide mitigation process.

Denitrification has long been regarded as the only pathway for terrestrial nitrogen (N) loss to the atmosphere. Here we demonstrate that large-scale anaerobic ammonium oxidation (anammox), an overlooked N loss process alternative to denitrification which bypasses nitrous oxide (N2O), is ubiquitous in inland waters of China and contributes significantly to N loss. Anammox rates in aquatic systems show different levels (1.0-975.9 µmol N m(-2) h(-1), n = 256) with hotspots occurring at oxic-anoxic interfaces and harboring distinct biogeochemical and biogeographical features. Extrapolation of these results to the China-national level shows that anammox could contribute about 2.0 Tg N yr(-1), which equals averagely 11.4% of the total N loss from China's inland waters. Our results indicate that a significant amount of the nitrogen lost from inland waters bypasses denitrification, which is important for constructing more accurate climate models and may significantly reduce potential N2O emission risk at a large scale.

[Influences of iron overload on lipid peroxidation in rats and inhibiting effects of antioxidant vitamins].

In order to explore the influences of iron overload on lipid peroxidation of rats and the inhibiting effects of antioxidant vitamins such as vitamin E and beta-carotene on the influences induced by iron overload, eighty male Wistar rats were randomly divided into 8 groups according to the weight. The diets of the former 4 groups differed only in iron concentration (50, 200, 350 or 500 mg/kg diet). The diet of the latter 4 groups were consistent with the former 4 groups respectively, but complemented with vitamin E(100 mg/kg diet) and beta-carotene (25 mg/kg.BW) at the same time. After Eight weeks, the levels of serum iron, blood lipid including total cholesterol TC, triglyceride TG, high density lipoprotein HDL, low density lipoprotein LDL, vitamin E, vitamin A, serum malondialdehyde (MDA) and oxidized low density lipoprotein (OX-LDL), the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were determined. Results showed that the iron overload increased the levels of MDA, OX-LDL and LDL in serum, especially in the group of rat with 500 mg/kg diet. The activity of GSH-Px increased irritably and the contents of Vitamin E and Vitamin A decreased significantly. Complementing antioxidant vitamins decreased the levels of MDA, OX-LDL and LDL and increased HDL and the activity of GSH-Px decreased compared with the corresponding iron overload groups. It was concluded that iron overload could promote lipid peroxidation reaction especially in 10 folds of physiologic dose and the activities of antioxidant enzymes increased at the same time to keep the body homeostasis. Antioxidant vitamins may play a role through non-enzymatic reactive system to inhibit the above changes.

Vitamin A deficiency aggravates iron deficiency by upregulating the expression of iron regulatory protein-2.

OBJECTIVE: The aim of this study was to investigate the mechanism between vitamin A deficiency and anemia. METHODS: In this study, we performed animal and in vitro experiments to investigate the effect of vitamin A deficiency on iron regulator protein-2 (IRP2). In animal experiments, four parallel groups of rats were fed a control diet, a diet completely deficient in vitamin A, a diet marginally deficiency in vitamin A, and a diet marginally deficient in iron and vitamin A, respectively, for 8 wk. In the in vitro experiments, the primary hepatocytes were acquired from the livers of vitamin A- and iron-depleted rats. Ferritin (Fn), transferrin receptor (TfR), and IRP2 mRNA were measured by semiquantitive reverse transcription polymerase chain reaction. RESULTS: As expected, a decrease in the serum retinol concentration and an imbalance of iron metabolism existed in the vitamin A-deficient rats. The IRP2 mRNA level of the rats in the test groups was approximately two times that of the control group, whereas the Fn mRNA level and the TfR mRNA level were downregulated and upregulated, respectively, by the vitamin A deficiency. In the in vitro experiments, all-trans-retinoic acid induced a decrease of the IRP2 mRNA level in hepatocytes, whereas the Fn, TfR, and IRP2 mRNA levels regulated by all-trans-retinoic acid were reversed by the vitamin A receptor blocker Ro41-5253. CONCLUSION: Taken together, our results indicate that vitamin A is involved in the regulation of IRP2, subsequently affecting iron metabolism gene expressions, such as Fn and TfR. Investigating the mechanistic connection between vitamin A and iron metabolism would be helpful to characterize the importance of this nutrient-nutrient interaction.

Body mass index and susceptibility to knee osteoarthritis: a systematic review and meta-analysis.

OBJECTIVE: Excess bodyweight, expressed as increased body mass index, is associated with osteoarthritis risk, especially in weight bearing joints. However, the strength of the association was inconsistent. The study was conducted to quantitatively assess the association between body mass index and the risk of knee osteoarthritis and investigate the difference of the strength stratified by sex, study type and osteoarthritis definition. METHODS: We used published guidelines of the Meta-analysis of Observational Studies in Epidemiology Group (MOOSE) to perform the meta-analysis. The search strategy employed included computerized bibliographic searches of MEDLINE, PubMed, EMBASE, The Cochran Library and references of published manuscripts. Study-specific incremental estimates were standardized to determine the risk of knee osteoarthritis associated with a 5 kg/m(2) increase in BMI. RESULTS: Twenty-one studies were included in the study. The results showed that body mass index was significantly positive associated with osteoarthritis risk in knee site. A 5-unit increase in body mass index was associated with an 35% increased risk of knee osteoarthritis (RR: 1.35; 95%CI: 1.21, 1.51). Magnitude of the association was significantly stronger in women than that in men with significant difference (men, RR: 1.22; 95%CI: 1.19, 1.25; women, RR: 1.38; 95%CI: 1.23, 1.54; p=0.04). The summary effect size was 1.25(95%CI: 1.18, 1.32) in case-control studies and 1.37 (95%CI: 1.19, 1.56) in cohort studies (p=0.28). Body mass index was positively associated with knee osteoarthritis defined by radiography and/or clinical symptom (RR: 1.25, 95%CI: 1.17, 1.35) and clinical surgery (RR: 1.54, 95%CI: 1.29, 1.83). The latter tended to be stronger than the former (p<0.01). CONCLUSION: Increased body mass index contribute to a substantially increased risk of knee OA. The magnitude of the association varies by sex and OA definition.

Anaerobic ammonia oxidation in a fertilized paddy soil.

Evidence for anaerobic ammonium oxidation in a paddy field was obtained in Southern China using an isotope-pairing technique, quantitative PCR assays and 16S rRNA gene clone libraries, along with nutrient profiles of soil cores. A paddy field with a high load of slurry manure as fertilizer was selected for this study and was shown to contain a high amount of ammonium (6.2-178.8 mg kg(-1)). The anaerobic oxidation of ammonium (anammox) rates in this paddy soil ranged between 0.5 and 2.9 nmol N per gram of soil per hour in different depths of the soil core, and the specific cellular anammox activity observed in batch tests ranged from 2.9 to 21 fmol per cell per day. Anammox contributed 4-37% to soil N2 production, the remainder being due to denitrification. The 16S rRNA gene sequences of surface soil were closely related to the anammox bacteria 'Kuenenia', 'Anammoxoglobus' and 'Jettenia'. Most of the anammox 16S rRNA genes retrieved from the deeper soil were affiliated to 'Brocadia'. The retrieval of mainly bacterial amoA sequences in the upper part of the paddy soil indicated that nitrifying bacteria may be the major source of nitrite for anammox bacteria in the cultivated horizon. In the deeper oxygen-limited parts, only archaeal amoA sequences were found, indicating that archaea may produce nitrite in this part of the soil. It is estimated that a total loss of 76 g N m(-2) per year is linked to anammox in the paddy field.