[Pollution characteristics and health risk assessment of heavy metals in PM(2.5) in Lanzhou].

Objective: To understand the pollution characteristics and assess the pollution health risks of heavy metals in atmospheric PM(2.5) in Lanzhou. Methods: According to the regional characteristics of air pollution and industrial distribution characteristics in Lanzhou, atmospheric PM(2.5) was sampled monthly in Chengguan and Xigu Districts from January, 2015 to December, 2016. Detected the concentration of PM(2.5) and 12 kinds of elements (Sb, Al, As, Be, Cd, Cr, Hg, Pb, Mn, Ni, Se and Tl) by weighing method and inductively coupled plasma mass spectrometry. Enrichment factor and geo-accumulation index were used to describe the pollution characteristics, while health risk assessment was conducted using the recommended United States Environmental Protection Agency (USA EPA) model. The health risks of non-carcinogens were evaluated by non-cancer hazard quotient (HQ), the non-carcinogenic risk was considered to be negligible when HQ<1, HQ>1 meant a health risk. With a single contaminant cancer Risk value to evaluate the health risks of carcinogens, when the Risk value between 10(-6) to10(-4) as an acceptable level. Results: The daily average concentrations of PM(2.5) was 83.0 µg/m(3), 77.0 µg/m(3) in Chengguan and Xigu Districts, respectively, during the sampling periods, and the concentration of PM(2.5) in winter/spring was higher than summer/fall in both districts. The concentration of Al in PM(2.5) was the highest and other elements in descending order: Pb, Mn, As, Sb/Cd, Tl in both districts. Enrichment factor results showed that Al and Mn were mainly affected by natural factors, the rest of five elements were all typical man-made pollution elements and according to geo-accumulation index pollution level of Cd was the strongest in the winter. The results of health risk assessment showed that Mn had the highest non-cancer risks (HQ>1) and affected the health of the children seriously. HQ reached up to 2.44 and 1.79 in Chengguan and Xigu Districts, respectively. Pb, As, Sb, Cd had slight health impact (HQ<1), could be negligible. The cancer risks range of As, Cr were 6.33×10(-6) to 6.46×10(-5) between the acceptable level of risk (10(-6) to 10(-4)), which indicated that As and Cd had potential cancer-risks. Conclusions: The pollution level of atmospheric PM(2.5) and the heavy metals in it was still grim;the non-cancer risks caused by multiple metals on children deserved attention. Although the cancer risks of As and Cd were between the acceptable level of risk, the potential cancer risk still shall not be ignored.

Evaluation of combined toxicity of phenols and lead to Photobacterium phosphoreum and quantitative structure-activity relationships.

The combined toxicity of lead (Pb) and nine phenols were measured. The result indicated that the combined toxicity is not only dependent on the Pb concentrations but also on the positions of substituted groups of phenols. Quantitative structure-activity relationship equations were built from the combined toxicity and physico-chemical descriptors of phenols in the different Pb concentrations. The combined toxicity was related to water solubility and the third order molecular connectivity index ((3)X) in low Pb concentration, to solute excess molar refractivity (E) and ionization constant (pKa) in medium Pb concentration and to dipolarity/polarizability (S) in high Pb concentration.

Repair of penile rupture through a high-scrotal midline raphe incision.

We report a case of penile rupture after a self-inflicted injury, which was repaired through a 4-cm midline raphe incision in the high-scrotal position. A single injury to the right lateral corpora cavernosum was identified and repaired. This incision allows for exposure of all three corporal bodies and results in excellent cosmesis. Creating artificial tumescence with intracorporal saline injection can be useful in identifying small or multiple sites of corporal injury. This may obviate the need for performing a routine degloving procedure, which results in unnecessary dissection, increased edema, and potential visible scarring of the penile skin.

Linear and non-linear relationships between soil sorption and hydrophobicity.

The relationship between log K (oc) and log P was examined by use of a large dataset. For most of the hydrophobic compounds (e.g. 0.5 < log P < 7.5), the organic carbon content plays a dominant role in soil sorption and the sorption coefficient is linearly related to the octanol/water partition coefficient. For hydrophilic compounds (e.g. log P < 0.5), hydrophobic sorption becomes less significant. The hydrophilic contribution to sorption is equal to, or higher than, the hydrophobic contribution to sorption, resulting in the observed K (oc) values being higher than those predicted from their log P values. For highly hydrophobic compounds (e.g. log P > 7.5), log K (oc) decreases with increasing hydrophobicity because of a lack of chemical availability due to low solubility. A linear solvation energy relationship shows that the sorption potential increases with increasing molecular size by increasing the dispersion interactions between the chemical and soil organic phase. The sorption potential decreases with increase in the basicity of hydrophobic compounds by increasing the H-bonding of chemicals with water. Principal component analysis shows that the octanol/water system is the closest system, but not an ideal surrogate, to describe the soil sorption for hydrophobic compounds as compared with other solvent/water partition systems.

Toxicity of organic pollutants to seven aquatic organisms: effect of polarity and ionization.

The toxicity of organic chemicals to Vibrio fischeri, river bacteria, algae, Daphnia magna and fishes were analysed. The results showed that the toxicity of chemicals to narcotics was dependent on hydrophobicity. A single model for both polar and non-polar narcotics was developed by inclusion of a polarity descriptor as well as the hydrophobic parameter. The highly hydrophobic polar narcotics could be treated as non-polar narcotics because their polar functional group(s) make(s) a relatively small contribution to polarity as compared with their hydrophobicity. In order to investigate the toxic mechanism of action for reactive compounds, the response-surface approach was used to develop models derived from easily calculated descriptors. The stepwise analysis selected the octanol/water partition coefficient and a polarity descriptor to parameterize bio-uptake and reactivity, respectively, for seven species. Benzoic acids can be easily absorbed into the unicellular bacteria, but this is not the case for multicellular D. magna and fish. Their toxicity to V. fischeri is much higher than that to D. magna and carp. Regression analysis was performed based on the model that we developed for ionizable compounds. Good correlations were observed by introducing the correction factor for ionizable compounds. The toxic mechanisms are discussed.

Physiological consequences of testicular sperm extraction.

Testicular sperm extraction (TESE) may provide spermatozoa for attempts at fertility with assisted reproduction; however, the physiological effects of TESE on testicular function are not well understood. In order to evaluate the effects of TESE on the testis, 64 patients were evaluated after TESE for non-obstructive azoospermia with physical examinations, serial scrotal sonography, histological analyses and evaluation of the success of repeated sperm retrieval attempts. At 3 months after TESE, 82% of evaluated patients had ultrasonographic abnormalities in the testis suggesting resolving inflammation or haematoma at the biopsy site. By 6 months, these acute inflammatory changes typically resolved leaving linear scars or calcifications. Two patients had documented impaired testicular blood flow, with complete devascularization of the testis for one patient after TESE with multiple biopsies. Repeat TESE procedures were far more likely to retrieve spermatozoa if the second TESE attempt was performed >6 months after the initial TESE procedure (80%), relative to those performed within 6 months (25%). Transient adverse physiological effects are common in the testis for up to 6 months after TESE. In addition, permanent devascularization of the testis can occur following TESE procedures with multiple biopsies. The risk of this complication may be minimized by using an open biopsy technique with optical magnification to directly identify testicular vessels.

The effect of varicocelectomy on serum testosterone levels in infertile men with varicoceles.

PURPOSE: We evaluated the effect of varicocelectomy on serum testosterone. MATERIALS AND METHODS: We retrospectively reviewed the effect of varicocelectomy on serum testosterone levels in 53 infertile men with varicoceles. RESULTS: Mean serum testosterone increased from a preoperative level of 319 +/- 12 to 409 +/- 23 ng./dl. postoperatively (p < 0.0004). Men with at least 1 firm testis preoperatively had a greater increase in serum testosterone (p < 0.005). An inverse correlation was noted between preoperative testosterone levels and change in testosterone after varicocelectomy (r = -0.34, p < 0.013). CONCLUSIONS: Varicocelectomy can increase serum testosterone for infertile men with varicoceles. Although improvement in serum testosterone does not necessarily cause a direct improvement in semen quality, varicocelectomy may improve hormonal and spermatogenic function.

Rapid ligation of renal hilum during transperitoneal laparoscopic nephrectomy.

We describe our surgical technique for rapid ligation of the renal hilum during transperitoneal laparoscopic nephrectomy. This technique is reliable and provides an efficient method of hilar ligation.

Massive hematuria due to right renal artery mycotic pseudoaneurysm in a patient with subacute bacterial endocarditis.

A 40-year-old woman with recently diagnosed bacterial endocarditis was admitted to the hospital with gross hematuria and anemia. Computed tomography revealed a large right upper pole renal artery pseudoaneurysm, a wedge-shaped hypoperfused region of the left kidney, and a splenic abscess. Radiographic embolization of the right renal artery was performed to stabilize the bleeding. The splenic abscess was drained. Subsequent right nephrectomy and splenectomy were performed for persistent leukocytosis. This unusual presentation of a septic embolus and its management are discussed.

Hand assisted laparoscopic donor nephrectomy: a comparison with the open approach.

PURPOSE: Hand assisted laparoscopy combines aspects of open and laparoscopic surgery. A hand in the abdomen may facilitate laparoscopic live donor nephrectomy, allowing more urologists to participate. We report and compare our initial series of hand assisted laparoscopy donor nephrectomy with nephrectomy performed by standard open methods. MATERIALS AND METHODS: In the last 18 months 60 patients at 2 institutions underwent hand assisted laparoscopy donor nephrectomy. This cohort was compared to a contemporary group of 31 patients who underwent open donor nephrectomy via a flank incision at our 2 institutions. Demographic and outcome data were compared retrospectively in a nonrandomized fashion in the 2 groups. RESULTS: Demographic data on patient age, male-to-female ratio and body mass index were similar in the 2 groups. Operative time, transfusion rate, time to oral intake and complications were also similar. However, estimated blood loss, change in hematocrit preoperatively to postoperatively, hospitalization, parenteral and oral narcotic requirement, and donor convalescence were significantly less in the hand assisted laparoscopy versus open groups. In terms of allograft function, nadir creatinine, time to nadir creatinine, creatinine clearance at 6, 12, and 18 months, delayed graft function, episodes of acute rejection and ureteral stricture were similar in the groups. CONCLUSIONS: Hand assisted laparoscopy is safe, efficacious and reproducible for living related donor nephrectomy. Compared with the open technique hand assisted laparoscopy provides the donor with significantly decreased postoperative morbidity, while enabling excellent allograft function. Further randomized prospective studies are warranted.

Testicular sperm extraction with intracytoplasmic sperm injection for nonobstructive azoospermia: testicular histology can predict success of sperm retrieval.

PURPOSE: We present treatment results of testicular sperm extraction with intracytoplasmic sperm injection for men with nonobstructive azoospermia and reevaluate the role of testicular histology on open diagnostic testicular biopsy as a predictor of sperm retrieval success. MATERIALS AND METHODS: We evaluated 75 men diagnosed with nonobstructive azoospermia. Cases were categorized into 3 groups of hypospermatogenesis, maturation arrest or Sertoli-cell-only based on the most advanced pattern of spermatogenesis seen on histology. A total of 81 testicular sperm extractions with intracytoplasmic sperm injection were performed for these 75 men. The main outcome measures reviewed included sperm retrieval, fertilization and pregnancy rates with intracytoplasmic sperm injection. Sperm retrieval success rates for men in the 3 histological categories were compared. RESULTS: Spermatozoa were successfully retrieved during 47 of 81 (58%) testicular sperm extraction attempts, with subsequent fertilization of 268 of 439 (61%) injected metaphase II oocytes using intracytoplasmic sperm injection. Clinical pregnancies were obtained in 26 of 47 (55%) cycles when sperm were retrieved, with ongoing pregnancies or live deliveries for 20 of 47 (43%). Of 39 men with hypospermatogenesis on diagnostic biopsy 31 (79%) had successful sperm retrieval, compared to 9 of 19 (47%) with maturation arrest and 5 of 21 (24%) with a pure Sertolicell-only pattern. CONCLUSIONS: Critical examination of the most advanced pattern of spermatogenesis from open diagnostic testis biopsy allows prediction of sperm retrieval success with testicular sperm extraction. In this study population spermatozoa were retrieved in 58% of attempts. When this testicular sperm was used with intracytoplasmic sperm injection, clinical pregnancy rate was 55% for men with nonobstructive azoospermia.

[Kidney function in spontaneously hypertensive rats under minoxidil treatment]. / Nierenfunktion bei spontan hypertonen Ratten unter Minoxidilbehandlung.

In 25 spontaneously hypertensive rats the blood pressure was lowered from 192 +/- 11.6 to 130 +/- 11.7 mm Hg and in 26 normotensive Wistar rats from 129 +/- 9.1 to 107 +/- 6.7 mm Hg by applying 1 mg/kg body weight minoxidil twice a day orally. 19 spontaneously hypertensive and 21 normotensive rats served as untreated control groups. During the treatment the glomerular filtration rate, determined by the slope clearance of Tc-99m-DTPA, remained unchanged. Under maximal water diuresis the excretion fraction of sodium was diminished compared with the control data. The Na+ and water reabsorption was increased in the proximal tubules (not an aldosterone effect) only in the treated spontaneously hypertensive rats. The potassium clearance was increased in this group, but decreased in the treated normotensive group. The different reactions of the renal tubular function to the treatment with minoxidil in spontaneously hypertensive compared with normotensive rats were discussed in connection with changes of membrane transport in essential hypertension.

Hemostatic laparoscopic partial nephrectomy: initial experience with the radiofrequency coagulation-assisted technique.

OBJECTIVES: The techniques for hemostasis after renal tumor excision have limited the widespread application of laparoscopic partial nephrectomy (LPN). To improve hemostasis and aid visualization, we report our experience with a novel radiofrequency coagulation (RFC) technique for LPN. METHODS: Ten patients underwent RFC-assisted LPN. The demographic and perioperative data were tabulated. Patients were positioned as for laparoscopic nephrectomy, and laparoscopic ports were placed. The kidney within Gerota's fascia was mobilized, and the fat overlying the tumor was carefully removed for pathologic evaluation. Under laparoscopic guidance, a radiofrequency probe was percutaneously inserted into the lesion and deployed to coagulate the lesion and a margin of normal parenchyma. Laparoscopic scissors were used to excise the lesion; additional hemostatic maneuvers were used selectively. RESULTS: The mean renal tumor size was 2.1 cm (range 1.0 to 3.2). The median operative time was 170 minutes and the median blood loss was 125 mL. The RFC technique resulted in complete tissue coagulation within the treated volume, thereby facilitating intraoperative visualization, minimizing blood loss, and permitting rapid and controlled tumor resection. The renal architecture was preserved, allowing accurate diagnosis of renal cell carcinoma and angiomyolipoma in 9 and 1 cases, respectively. No perioperative complications occurred. CONCLUSIONS: The use of RFC is an effective method to facilitate LPN of both exophytic and endophytic masses. By coagulating a margin of normal parenchyma, the technique minimizes blood loss and improves visualization during LPN. We anticipate this technique will broaden the clinical application for LPN.