[Effects of 24 Years Different Straw Return on Soil Carbon, Nitrogen, Phosphorus, and Extracellular Enzymatic Stoichiometry in Dryland of the Loess Plateau, China].

Exploring the biogeochemical cycle characteristics of soil carbon, nitrogen, and phosphorus in farmland in the dryland of the loess plateau can provide scientific basis and technical support for efficient crop production and sustainable land use. Here, based on a long-term (24 year) straw return field experiment in Shouyang, Shanxi province, the effects of different straw return regimes, i.e., straw mulching (SM), direct straw return (DS), animal-digested straw return (AS), and non-straw return (CK), on the stoichiometric ratio of soil elements and extracellular enzyme activities were studied. The vector angle and length were calculated to indicate the resource constraints faced by microorganisms. The vector angle was greater than 45° and less than 45°, indicating that microorganisms were limited by phosphorus and nitrogen, respectively. The greater the deviation from 45°, the greater the degree of limitation, and the longer the vector length, the more severely limited by carbon. The results showed that ① the soil C/N and C/P of long-term straw returning ranged from 9.81 to 14.28 and from 14.58 to 21.92, with the mean values of 12.36 and 17.51, respectively, which were 6.0% and 4.2% lower than that at the initial stage of the experiment. The soil N/P was distributed between 1.27 and 1.57, with an average of 1.42, which was 2.2% higher than that in the initial stage. The soil C/N and C/P ratios showed a trend of first decreasing and then increasing, the soil N/P ratio basically showed a flat trend, and there was no significant difference in soil element metering ratios between different straw returning treatments. ② Compared with the 24-year long-term non-straw return treatment, the activities of ß-1,4-glucosidase (BG) and ß-1,4-N-acetylglucosaminidase (NAG) in the soil of the long-term straw mulching treatment increased by 134.4% and 107.5% (P<0.05), the activities of BG and alkaline phosphatase (AP) in the soil of the long-term straw mulching treatment decreased by 59.3% and 59.5% (P<0.05), respectively, and the activities of NAG in the soil of the long-term straw mulching treatment increased by 102.8% (P<0.05). Under the long-term straw returning treatment, soil microorganisms were faced with carbon and phosphorus limitation as a whole. Long-term straw mulching aggravated microbial carbon limitation, and animal-digested straw return could alleviate the degree of carbon limitation. Compared with that in the 24-year long-term non-straw return treatment, soil EEAC/N could be significantly reduced by the animal-digested straw return treatment, and soil EEAC/P could be increased by the direct straw return treatment. The three straw returning methods had no significant indigenous effect on soil EEAN/P. The overall vector angle was greater than 45°, and the vector length increased by 3.8%-20.1% compared with that in the initial stage. ③ Correlation analysis showed that C and N inputs were significantly negatively correlated with BG activity; available nitrogen was significantly correlated with NAG activity, AP activity, and EEAC/N; C/P was significantly positively correlated with EEAC/N; there were significant correlations between N/P and NAG activity, AP activity, EEAC/N, and EEAC/P; and there was no significant correlation between EEAN/P and any environmental factors. In conclusion, the availability of soil nitrogen and phosphorus elements and N/P ratio had significant effects on soil extracellular enzyme activity and stoichiometric characteristics under different long-term straw returning treatments. In the future, more attention should be paid to the improvement of organic carbon and the promotion of nitrogen and phosphorus availability in farmland soil in soil-efficient cultivation and agricultural production activities.

A Contemporary Evaluation of Urological Outcomes After Renal Transplantation.

INTRODUCTION: Urological surgery after renal transplantation leaves patients at risk of infection and further urological complications. Our objective was to discern patient factors associated with adverse outcomes following renal transplantation to identify patients who would benefit from close urological follow-up. METHODS: Retrospective chart review was conducted for patients undergoing renal transplantation between August 1, 2016 and July 30, 2019 at a tertiary care academic center. Data on patient demographics, medical history, and surgical history were collected. Primary outcomes observed were urinary tract infection, urosepsis, urinary retention, unexpected urology visit, and urological procedures within 3 months of transplant. Variables determined significant by hypothesis testing were used in logistic regression modeling for each primary outcome. RESULTS: Of the 789 renal transplant patients, 217 (27.5%) developed postoperative urinary tract infection and 124 (15.7%) developed postoperative urosepsis. Patients with postoperative urinary tract infection were more likely to be female (OR 2.2, P < .01), have pre-existing prostate cancer (OR 3.1, P < .01), and recurrent urinary tract infections (OR 2.1, P < .01). After renal transplant, unexpected urology visits were observed in 191 (24.2%) patients, and urological procedures were performed in 65 (8.2%) patients. Postoperative urinary retention was noted in 47 (6.0%) patients and seen more often in patients with benign prostatic hyperplasia (OR 2.8, P = .033) and prior prostate surgery (OR 3.0, P = .072). CONCLUSIONS: Identifiable risk factors associated with urological complications after renal transplantation include benign prostatic hyperplasia, prostate cancer, urinary retention, and recurrent urinary tract infections. Female renal transplant patients are at increased risk of postoperative urinary tract infection and urosepsis. These patient subsets would benefit from establishing urological care and pre-transplant urological evaluation including urinalysis, urine cultures, urodynamic studies, and close follow-up post-transplant.

Dietary supplementation with acidifiers improves the growth performance, meat quality and intestinal health of broiler chickens.

This experiment was conducted to study the effects of dietary supplementation with acidifiers on the growth performance, meat quality, and intestinal health of broiler chickens. A total of 648 male Arbor Acres broiler chickens at 1 d old were randomly divided into 6 groups, and each group consisted of 6 replicates with 18 broilers per replicate. The dietary treatments were as follows: negative control (NC, the basal diet), NC + antibiotic (enramycin, 8 mg/kg, positive control [PC]), NC + phosphoric acid (PA, 0.1, 0.2, and 0.3 g/kg), and NC + lactic acid (LA, 0.3 g/kg). The feeding trial lasted for 42 d. The results showed that the feed-to-gain ratio of the NC + acidifier groups was lower than that of the NC and PC groups from 1 to 42 d (P < 0.05). Compared with the values in the NC group, the pH of breast muscle was significantly higher in the NC + PA (0.2 g/kg) and LA (0.3 g/kg) groups (P < 0.05), and the cooking loss was lower in the breast muscle of the NC + PA (0.1 g/kg) and LA (0.3 g/kg) groups (P < 0.05). In addition, the shear force of the breast muscle and thigh muscle and the pH value in the crop, gizzard and duodenum of the antibiotic and acidifier groups were significantly decreased (P < 0.05). Moreover, the trypsin, chymotrypsin, and lipase activities of the duodenum in the NC + PA (0.2 and 0.3 g/kg) groups, as well as the villus height-to-crypt depth (VH:CD) ratio of the duodenum in the NC + PA (0.1 g/kg) group was significantly greater (P < 0.05) compared with those in the NC group. Meanwhile, the number of total aerobic bacteria, Escherichia coli and Salmonella in the cecum of the NC + PA (0.1 g/kg) and LA (0.3 g/kg) groups were decreased (P < 0.05). Collectively, diet supplementation with acidifiers could improve the growth performance, meat quality, and intestinal health of broilers, in which the effects of PA (0.1 g/kg and 0.2 g/kg) are better than the other supplementations.

Causes of Renal Allograft Injury in Recipients With Normal Donor-derived Cell-free DNA.

BACKGROUND: Donor-derived cell-free DNA (dd-cfDNA) is a noninvasive biomarker for the early detection of organ transplant rejection and other causes of graft injury. For nonrejection renal injuries, there is little information about the performance characteristics of this biomarker. We highlight some of the possible causes of kidney injury that may arise in patients with normal dd-cfDNA levels. METHODS: We performed a retrospective analysis of solitary renal transplant cases between January 2017 and November 2019. Those who had an abnormal laboratory or pathological finding within 1 mo of a normal dd-cfDNA test were selected. Subgroups were stratified for those who had normal or abnormal/rising serum creatinine, and differences between the groups were analyzed. RESULTS: Of 414 individuals who received a kidney transplant, 24 (7.5%) had a total of 41 normal dd-cfDNA values and 51 abnormal laboratory tests or histologic findings. The most common graft-injuring event was BK virus viremia (24 of 51). Other abnormal findings included urinary traction infections (n = 4), CMV viremia (n = 4), and biopsies demonstrating antibody-mediated rejection (AMR) (n = 2), T cell-mediated rejection (n = 1), focal segmental glomerulosclerosis (n = 2), nondonor-specific antibody chronic AMR (n = 1), and interstitial fibrosis and tubular atrophy (n = 7). Subgroup analysis of those with normal dd-cfDNA and normal/stable versus abnormal/rising creatinine showed that BK virus viremia was the most common abnormal finding in both groups at 53% and 38% respectively. On biopsy, 1 case of acute T cell-mediated rejection (1B and 2B) was seen with normal/stable creatinine, whereas 1 of nonspecific C4d focally positive and 1 of nondonor-specific antibody AMR were seen with abnormal/rising creatinine. CONCLUSIONS: Low levels of serum dd-cfDNA do not preclude detection of active graft-injuring events and that subclinical injuries may be developing. Context is important in the interpretation of dd-cfDNA, so renal biopsy remains a part of the diagnostic pathway for allograft dysfunction and maintenance of allograft health.

A Comparison of Guided Video Reflection versus Self-Regulated Learning to Teach Knot Tying to Medical Students: A Pilot Randomized Controlled Trial.

OBJECTIVES: Self-regulated learning has been proposed as a resource saving alternative for learning knot tying. However, this may be hindered by the Dunning-Kruger effect. A potential alternative is guided video reflection. The objectives of this study are to compare the performance and self-assessment abilities amongst medical students learning knot tying using either a traditional self-regulated approach versus guided video reflection. DESIGN: This randomized, single-blinded, controlled trial used a pre-post-retention test design. All knot tying performances were video recorded and assessed nonsequentially by blinded evaluators using a modified Objective Structured Assessment of Technical Skills tool. PARTICIPANTS: This study recruited 31 first- and second-year medical students and 6 senior urology residents from Western University in Canada. RESULTS: At baseline, the performances of the experts were significantly higher than the experimental groups (F3,85 = 9.080, p < 0.001). After the intervention, there was a significant increase in the performance for both experimental groups compared to the pretest period (p < 0.001). The scores between the experimental groups were not significantly different (p = 0.338). The improved performances of both groups were sustained on retention testing (p < 0.001). The self-assessment abilities were accurate for both experimental groups at baseline. However, at the post-test period the accuracy was poor (interclass correlation 0.361) for the self-regulated group, while remaining moderately (interclass correlation 0.685) accurate for the reflection group. CONCLUSIONS: Students using guided video reflection were able to achieve competency and maintained their knot tying skills to the same degree as those who used the self-regulated approach. These results may be due to the positive effects of reflection on self-assessment abilities and subsequent improvement in goal setting for further practice.

Dietary supplementation with pioglitazone hydrochloride improves intramuscular fat, fatty acid profile, and antioxidant ability of thigh muscle in yellow-feathered chickens.

BACKGROUND: Muscle fat content and fatty acid composition play an important role in poultry flavor and taste. To investigate the effects of pioglitazone hydrochloride (PGZ) on growth performance and thigh muscle quality in yellow-feathered chickens, 360 female chickens were randomly divided into three groups and treated with three doses of PGZ (0, 7.5, and 15 mg kg-1 ) for 28 days. Each group had six replicates of 20 chickens. RESULTS: The results showed that dietary supplementation with 15 mg kg-1 PGZ increased average daily feed intake (ADFI) and the average daily gain (ADG) from 0 to 14 days. Furthermore, the triglyceride (TG) level was decreased by 15 mg kg-1 PGZ, whereas the eviscerated yield was increased. The relative weight of the heart and kidneys showed a linear increase with dietary PGZ supplementation, and the drip loss of the thigh muscle was significantly decreased by 15 mg kg-1 PGZ supplementation. Moreover, a* value, intramuscular fat (IMF), and polyunsaturated fatty acids (PUFAs) showed a linear increase, and pH24 h and drip loss showed a quadratic influence with the levels of PGZ supplementation. In particular, the PUFA proportion was increased by 7.63% and 9.14% in the 7.5 mg kg-1 PGZ and 15 mg kg-1 PGZ groups, respectively. Additionally, 15 mg kg-1 of PGZ increased the total antioxidant capacity (T-AOC) and glutathione peroxidase (GSH-PX ) activity. CONCLUSION: In summary, 15 mg kg-1 PGZ has substantial effects on growth performance and meat quality, particularly by decreasing drip loss and increasing IMF content, PUFA proportions, and antioxidant ability. © 2019 Society of Chemical Industry.

Molecular Signaling and Nutritional Regulation in the Context of Poultry Feather Growth and Regeneration.

The normal growth and regeneration of feathers is important for improving the welfare and economic value of poultry. Feather follicle stem cells are the basis for driving feather development and are regulated by various molecular signaling pathways in the feather follicle microenvironment. To date, the roles of the Wnt, Bone Morphogenetic Protein (BMP), Notch, and Sonic Hedgehog (SHH) signaling pathways in the regulation of feather growth and regeneration are among the best understood. While these pathways regulate feather morphogenesis in different stages, their dysregulation results in a low feather growth rate, poor quality of plumage, and depilation. Additionally, exogenous nutrient intervention can affect the feather follicle cycle, promote the formation of the feather shaft and feather branches, preventing plumage abnormalities. This review focuses on our understanding of the signaling pathways involved in the transcriptional control of feather morphogenesis and explores the impact of nutritional factors on feather growth and regeneration in poultry. This work may help to develop novel mechanisms by which follicle stem cells can be manipulated to produce superior plumage that enhances poultry carcass quality.

Separation and Analysis of Sucrose Esters in Tobacco by Online Liquid Chromatography-Gas Chromatography/Mass Spectrometry.

In this work, a strategy of in-series combination of ultrasound-assisted extraction and online LC-GC/MS was constructed for effective separation and analysis of sucrose esters in tobacco. Sucrose esters were first extracted by ultrasound-assisted extraction with high efficiency and easyhandling. Online LC-GC/MS was then applied for sucrose ester clean-up and analysis. To better evaluate the effectiveness of this strategy, we limited our focus to five groups of sucrose ester isomers. Each group differed in mass from the next by 14 Da. The obtained coefficient of the calibration curve was 0.9986. Limit of detection (LOD) and limit of quantitation (LOQ) were 0.05 and 0.16 µg/ mL, respectively. The recovery was above 90% and the reproducibility was below 4%. This strategy was subsequently applied to the comparison of relative amounts of five groups of sucrose esters extracted from three different parts of aromatic tobacco. The satisfactory performance indicated that this strategy has great prospect for the rapid and high-throughput analysis of sucrose esters in tobacco.

Retroperitoneal Compartment Syndrome in Renal Transplantation: How to Salvage the Graft?

OBJECTIVE: Early allograft dysfunction may be caused by several technical factors including vascular complications such as thrombosis, kinking, or extrinsic compression. Renal allograft compartment syndrome (RACS) is an unrecognized cause of early allograft dysfunction. This complication is characterized by increased pressure of the iliac fossa that reduces the blood supply to the graft with a potentially devastating consequence. The main objective when recognizing this condition is to create a tension-free muscle closure. Many approaches have been proposed involving mesh such as the mesh hood fascial closure technique.1-4 PATIENT AND METHODS: We describe in the video an RACS during an operation. The recipient is a 23-year-old young man with a body mass index of 22, with renal failure secondary to chronic reflux. Past history of failure to peritoneal dialysis currently on hemodialysis. He received a living donor's kidney. After performing a standard anastomosis, his urine output was brisk. The fascia was then closed with no force, at which point he stopped making urine. A RACS was suspected; intraoperative examination and ultrasound showed no flow in the graft, with no signs of kinking. Immediately, reexploration was performed, showing the graft with abnormal color and turgor. After relieving the pressure, the graft returned to normal. The closure was redone with a large ellipsoid piece of polypropylene mesh draped loosely and without tension over the graft. RESULTS: A Doppler ultrasound, after the skin closure was performed, showed good flow, and the postoperative course was unremarkable. There was minimal bulking in the right iliac area, making it cosmetically acceptable. CONCLUSION: RACS could be associated with a lack of compliance in the retroperitoneal cavity.5 The RACS required a prompt intervention. The timely suspicion is a watershed in the prognosis of this rare pathology. We propose that mesh hood fascial closure is easy, effective, and a safe method to treat these complications.

An innovative cycling exergame to promote cardiovascular fitness in youth with cerebral palsy.

OBJECTIVE: To evaluate the effects of an internet-platform exergame cycling programme on cardiovascular fitness of youth with cerebral palsy (CP). METHODS: In this pilot prospective case series, eight youth with bilateral spastic CP, Gross Motor Functional Classification System (GMFCS) level III, completed a six-week exergame programme. Outcomes were obtained at baseline and post-intervention. The primary outcome measure was the GMFCS III-specific shuttle run test (SRT-III). Secondary outcomes included health-related quality of life (HQL) as measured by the KIDSCREEN-52 questionnaire, six-minute walk test, Wingate arm cranking test and anthropomorphic measurements. RESULTS: There were significant improvements in the SRT-III (t = -2.5, p = 0.04, d = 0.88) post-intervention. There were no significant changes in secondary outcomes. CONCLUSION: An exergame cycling programme may lead to improvement in cardiovascular fitness in youth with CP. This study was limited by small sample size and lack of a comparison group. Future research is warranted.

R237 and h238 are key amino acids in the rubella virus E1 neutralization epitope.

Residues 221-239 of rubella virus E1 glycoprotein contain antibody neutralization domains, and the solvent-exposed charged amino acids at the binding interface may be crucial for binding ability. However, the role of charged amino acid residues on the E1 epitope in peptide-antibody binding is unknown. To investigate the role of single amino acid substitutions on the important neutralizing epitope, biolayer interferometry and serological tests were performed. There are three charged residues in the neutralizing epitope: D229, R237, and H238. Substitution of D229 for amino acid A had no influence on the binding activity of the antibody to the peptide. However, substitutions of R237 or H238 for charged amino acid H or R were found to abolish the binding activity. Furthermore, substitution of an uncharged amino acid Q236 for a charged amino acid D was found to reduce the binding activity significantly. Thus, R237 and H238 are key amino acids in the rubella virus E1 neutralization epitope.

Characteristics of pain in children and youth with cerebral palsy.

OBJECTIVES: Pain in children with cerebral palsy (CP) is underrecognized, undertreated, and negatively affects quality of life. Communication challenges and multiple pain etiologies complicate diagnosis and treatment. The primary objectives of this study were to determine the impact of pain on activities and to identify the common physician-identified causes of pain in children and youth ages 3 to 19 years across all levels of severity of CP. METHODS: The study design was cross-sectional, whereby children/youth aged 3 to 19 years and their families were consecutively recruited. The primary caregivers were asked to complete a one-time questionnaire, including the Health Utilities Index 3 pain subset, about the presence and characteristics of pain. The treating physician was asked to identify the presence of pain and provide a clinical diagnosis for the pain, if applicable. RESULTS: The response rate was 92%. Of 252 participants, 54.8% reported some pain on the Health Utilities Index 3, with 24.4% of the caregivers reporting that their child experienced pain that affected some level of activities in the preceding 2 weeks. Physicians reported pain in 38.7% and identified hip dislocation/subluxation, dystonia, and constipation as the most frequent causes of pain. CONCLUSIONS: One-quarter of our sample experienced pain that limited activities and participation. Clinicians should be aware that hip subluxation/dislocation and dystonia were the most common causes of pain in children/youth with CP in this study. Potential causes of pain should be identified and addressed early to mitigate the negative impact of pain on quality of life.

[Lead and cadmium pollution in edible fungus sold in Beijing].

OBJECTIVE: To investigate the lead and cadmium pollution in edible mushrooms sold in Beijing. METHODS: 146 samples of 14 species were collected form 25 markets during the period of Mar. through May, 2007 in Beijing. The pollution of lead and cadmium were analyzed respectively according to the standard of GB/T5009. 12-2003 and GB 7096-2003. RESULTS: The content of lead and cadmium in edible mushrooms was ND--1.592 mg/kg, ND--0.550 mg/kg, respectively, both lower than the allowable content prescribed by The National Ministry of Health. CONCLUSION: The contents of lead and cadmium in the mushrooms marketed in Beijing are in safe ranges. It is worthy of mentioning the variation coefficients of heavy metal concentrations existing in edible mushrooms.

[Reducing oxidative DNA damage by adding antioxidants in human semen samples undergoing cryopreservation procedure].

OBJECTIVE: To evaluate the protective effects of oxidative DNA damage by adding antioxidants: ascorbate, catalase (CAT), and superoxide dismutase (SOD) in human semen samples undergoing cryopreservation procedure. METHODS: Semen sample form 30 fertile men were mixed with modified cryoprotectant and divided into six groups according to the category and concentration of antioxidants: ascorbate 300 micromol/L, ascorbate 600 micromol/L, CAT 200 U/ml, CAT 400 U/ml, SOD 200 U/ml, and SOD 400 U/ml. Comet assay was conducted to measure the percentage of comet cells, and the nuclear DNA damaged parameters: tail DNA percentage (TD%) and Olive tail moment (OTM). Flow cytometry was used to detect the reactive oxidative species (ROS). The motility (a + b grade), viable recovery rate, nuclear DNA integrity and reactive oxidative species (ROS) of all groups were analyzed before and/or after freeze-thawing. RESULTS: (After cryopreservation, compared with the control group, the a + b grade sperm rates of the ascorbate 300 micromol/L, CAT 200 U, and CAT 400 U groups were all higher than that of the control group (all P < 0.05), however, the levels of reactive oxygen species (ROS) of the ascorbate 300 micromol/L, CAT 200 U, and CAT 400 U groups were 30 +/- 13, 30 +/- 11, and 30 +/- 11 respectively, all significantly lower than that of the control group (37 +/- 17 , all P < 0.05). The viable recovery rates of the ascorbate 300 micromol/L , CAT 200 U, and CAT 400 U groups were 67% +/- 14%, 68% +/- 14%, and 69% -/+ 15% respectively, all significantly higher than that of the control group (59% +/- 10%, all P < 0.05). (2) The TD% levels of the ascorbate 300 micromol/L, CAT 200 U, and CAT 400 U groups were 41% +/- 4%, 40% +/- 7%, 40% +/- 6%, all similar to that of the raw semen (all P > 0.05), but significantly lower than that of the control group (46% +/- 6%, all P < 0.01). The OTM levels of the ascorbate 300 micromol/ L, CAT 200 U, and CAT 400 U groups were 7.7 +/- 1.2, 7.5 +/- 1.6, and 7.8 +/- 1.9, all similar to that of the raw semen (all P > 0.05), but significantly lower than that of the control group (10.1 +/- 3.1, all P < 0.01) too. The TD% and OTM levels of the other groups were all significantly higher than that of the raw semen (all P < 0.01), but not significantly different from those of the control group (all P > 0.05). (3) ROS was significantly negatively correlated with the motility in all groups (P < 0.05 or P < 0.01). Apart from the ascorbate 600 micromol/L group, the TD% and OTM of the other groups were all significantly positively correlated with the ROS (P < 0.05 or P < 0.01). CONCLUSION: Supplementation of ascorbate or CAT reduces the level of ROS that induces sperm nuclear DNA damage, and improves the human sperm quality in the process of freeze-thawing.