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Black locust coppice stands homogenize soil diazotrophic communities by reducing soil net nitrogen mineralization

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Forest Ecosystems 2022年第3期9卷 289-300页

作者： Kun Li Huimei Tian W.Keith Moser Steven T.Overby L.scott baggett Ruiqiang Ni Chuanrong Li Weixing Shen Mountain Tai Forest Ecosystem Research Station of State Forestry Administration Key Laboratory of State Forestry Administration for Silviculture of the Lower Yellow RiverForestry College of Shandong Agricultural UniversityTai'an271018ShandongChina Rocky Mountain Research Station United States Forest Service2500 S.Pine Knoll Dr.FlagstaffAZ86001USA Rocky Mountain Research Station United States Forest Service240 West Prospect Fort CollinsCO80526USA Mount Tai Scenic Spot Management Committee Tai'an271000ShandongChina

Background:Black locust(BL,Robinia pseudoacacia)is considered a promising tree species for reforestation due to its great ability to fix nitrogen.However,after two or three coppice-harvesting rotations,the productivity of BL declines.Whether soil microbial communities are affected and how these groups correlate with the nitrogen mineralization process across multi-generation stands remains unclear.Methods:We investigated the composition and structure of free-living nitrogen-fixing microorganisms(diazotrophs)by sequencing the marker gene nifH and compared these results to levels of soil nitrogen mineralization in the bulk soil and rhizosphere in black locust plantations on Mount Tai,China.Results:The results showed multi-generation BL coppice plantations decreased the total soil nitrogen(N),soil phosphorus(P),soil microbial biomass N(MBN),soil microbial biomass C(MBC),soil nitrification rate(Rn),soil ammonification rate(Ra),and net soil N mineralization rate(Rm),but significantly increased the concentration of soil NH_(4þ)-N to maintain sufficient NO_(3)^(-)N.The dominant species in bulk soil and rhizosphere changed from Rhodopseudomonas(22.62%and 15.76%),unclassified_c_Alphaproteobacteria(22.37%and 29.28%),unclassified_o_Rhizobiales(15.40%and 13.31%),Bradyrhizobium(12.00%and 11.74%)in seedling plantations to Bradyrhizobium(45.95%and 47.86%)and Rhodopseudomonas(43.56%and 41.84%)in coppice plantations,respectively.Mantel test and Redundancy analysis(RDA)revealed that Rn,Ra,and Rm were the most important factors shaping the diazotrophic communities.Conclusions:Our results suggest that the multi-generation BL coppice plantation can homogenize soil diazotrophic communities,which is mainly regulated by the available N loss caused by nitrogen mineralization.Strengthening the management technology of coppice plantations will provide more beneficial external consumption.

关键词： Black locust plantation nifH gene Nitrogen mineralization Coppice Soil nutrient

Haemostatic management for aortic valve replacement in a patient with advanced liver disease

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世界临床病例杂志 2014年第10期2卷 596-603页

作者： Laurence Weinberg Irene Kearsey Clarissa Tjoakarfa George Matalanis Sean Galvin scott Carson Rinaldo Bellomo larry McNicol Peter McCall Department of Anaesthesia Austin HospitalMelbourne Victoria 3084 Australia Department of Cardiac Surgery Austin HospitalMelbourne Victoria 3084 Australia Department of Intensive Care Austin HospitalMelbourne Victoria 3084 Australia

Redo-sternotomy and aortic valve replacement in patients with advanced liver disease is rare and associated with a prohibitive morbidity and mortality. Refractory coagulopathy is common and a consequence of intense activation of the coagulation system that can be triggered by contact of blood with the cardiopulmonary bypass circuitry, bypass-induced fibrinolysis, plate-let activation and dysfunction, haemodilution, surgical trauma, hepatic decompensation and hypothermia. Management can be further complicated by right heart dysfunction, porto-pulmonary hypertension, poor myocardial protection, and hepato-renal syndrome. Complex interactions between coagulation/fibrinolysis and systemic inflammatory response syndrome reactions like "post-perfusion-syndrome" also compound haemostatic failure. Given the limited information available for the specific management and prevention of cardiopulmonary bypass-induced haemostatic failure, this report serves to guide the anaesthesia and medical management of future cases of a similar kind. We discuss our multimodal management of haemostatic failure using pharmacological strategies, thromboelastography, continuous cerebral and liver oximetry, and continuous cardiac output monitoring.

关键词： Cardiac surgery Liver failure Coagulopathy Cardiopulmonary bypass

Color Doppler ultrasound imaging in varicoceles: Is the difference in venous diameter encountered during Valsalva predictive of palpable varicocele grade?

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Asian Journal of Urology 2023年第1期10卷 27-32页

作者： Kelly Lehner Catherine Ingram Utsav Bansal Colleen Baca Adithya Balasubramanian Nannan Thirumavalavan Jason M.Scovell Saneal Rajanahally Matthew Pollard larry I.Lipshultz Baylor College of Medicine Scott Department of UrologyHoustonTXUSA

Objective:The clinical grading system for varicoceles is subjective and dependent on clinician experience.Color Doppler ultrasound(US)has not been standardized in the diagnosis of varicoceles.We aimed to determine if US measurement of varicocele could be predictive of World Health Organization(WHO)varicocele grade.Methods:Men who presented for either scrotal pain or infertility to a tertiary men’s health clinic underwent physical examination,and varicoceles were graded following WHO criteria(0Zsubclinical,1,2,3).US was used to measure largest venous diameter in the pampiniform plexus bilaterally at rest and during Valsalva maneuver.Receiver operator characteristic curve analysis was used to determine if resting diameter,diameter during Valsalva,or change in diameter between at rest and during Valsalva provided the highest sensitivity and specificity for determining clinical grade.Threshold values for diameter were determined from these receiver operator characteristic curves.Results:A total of 102 men(50 with clinical varicocele and 52 with subclinical varicocele)were included.Diameter at rest was the best ultrasonographic discriminator between subclinical and clinical varicoceles(area under the curve[AUC]Z0.67)with a diameter threshold of 3.0 mm(sensitivity 79%,specificity 42%).Diameter during Valsalva had the greatest AUC for determining clinical Grades 1 versus 2(AUCZ0.57)with diameter threshold of 5.7 mm(sensitivity 71%,specificity 33%).For differentiating between Grades 2 and 3,diameter at rest had the greatest AUC of 0.65 with a threshold of 3.6 mm(sensitivity 71%,specificity 58%).Conclusion:Our results corroborate other studies that have shown a weak correlation between US and clinical grading.The use of diameter during Valsalva was less predictive than diameter at rest and was only clinically significant in differentiating between Grade 1 and 2 varicocele.A standardized method for determining clinically relevant varicoceles on US would allow for improved patient counseling and clinical decision-making.

关键词： Varicocele Ultrasound Doppler Venous plexus Infertility

The varicocele： diagnostic dilemmas, therapeutic challenges and future perspectives

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Asian Journal of Andrology 2016年第2期18卷 276-281,J0007页

作者： Koji Chiba Ranjith Ramasamy Dolores J Lamb larry I Lipshultz Center for Reproductive Medicine Baylor College of Medicine Houston TX USA scott Department of Urology Baylor College of Medicine Houston TX USA Department of Molecular and Cellular Biology Baylor College of Medicine Houston TX USA.

A varicocele is defined as the abnormal dilation of the internal testicular vein and pampiniform venus plexus within the spermatic cord. If a semen analysis is not obtained from the adolescent male, in the absence of other symptoms, the main clinical indication used by many urologists to recommend repair is testicular atrophy. The varicocele may result in testicular damage in some males causing testicular atrophy with impaired sperm production and decreased Leydig cell function, while in other males the varicocele may seemingly cause no ill effects. In adult men, varicoceles are frequently present and surgically correctable, yet the measurable benefits of surgical repair are slight according to a Cochrane review. While occurring more commonly in infertile men than fertile men, only 20% of men with a documented varicocele will suffer from fertility problems. Most varicoceles found in adolescents are detected during a routine medical examination, and it is difficult to predict which adolescent presenting with a varicocele will ultimately show diminished testicular function in adolescence or adulthood. As in adults, the mainstay of treatment for varicocele in adolescents is surgical correction. However, unlike an adult varicocelectomy （the microsurgical approach is the most common）, treatment for an adolescent varicocele is more often laparoscopic. Nevertheless, the goals of treatment are the same in the adolescent and adult patients. Controversy remains as to which patients to treat, when to initiate the treatment, and what type of treatment is the best. This review will present the current understanding of the etiology, diagnosis and treatment of the adolescent varicocele.

关键词： adolescent adult management varicocele

Sperm counts and sperm sex ratio in male infertility patients

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Asian Journal of Andrology 2012年第5期14卷 683-686页

作者： Michael L Eisenberg Lata Murthy Kathleen Hwang Dolores J Lamb larry I Lipshultz Department of Urology Stanford University School of Medicine Stanford CA 94305 USA scott Department of Urology Baylor College of Medicine Houston TX 77030 USA Department of Urology Brown University Providence RI 02912 USA

In recent years, investigators have noted a trend toward a declining proportion of male births in many industrialized nations. While men bear the sex-determining chromosome, the role of the female partner as it pertains to fertilization or miscarriage may also alter the gender ratio. We attempted to determine a man＇s secondary sex ratio （F1 generation） by directly examining the sex chromosomes of his sperm. We examined our male infertility clinic database for all men who had undergone a semen fluorescence in situ hybridization （FISH）. Patient demographic and semen parameters were recorded. Chi-squared analysis was used to compare gender ratios （Y chromosomes/total chromosomes）. Multivariable logistic regression was used to predict the odds of possessing a Y-bearing sperm after accounting for demographic and semen parameters. A total of 185 men underwent sperm FISH. For the entire cohort, the proportion of Y chromosome-bearing sperm was 51.5%. Men with less than five million motile sperm had a significantly lower proportion of Y chromosome-bearing sperm （50.8%） compared to men with higher sperm counts （51.6%; P= 0.02）. After multivariable adjustment, a higher sperm concentration, total motile sperm count and semen volume significantly increased the odds of having a Y chromosome-bearing sperm （P〈0.01）. As a man＇s sperm production declines, so does the proportion of Y chromosome-bearing sperm. Thus, a man＇s reproductive potential may predict his ability to sire male offspring.

关键词： infertility sex ratio spermatogenesis sperm chromosomes

Sperm retrieval and intracytoplasmic sperm injection outcomes in men with cystic fibrosis disease versus congenital bilateral absence of the vas deferens

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Asian Journal of Andrology 2021年第2期23卷 140-145页

作者： J Abram McBride Taylor P Kohn Daniel J Mazur larry I Lipshultz R Matthew Coward scott Department of Urology Baylor College of MedicineHoustonTX 77030USA Department of Urology UNC School of MedicineChapel HillNC 27599USA UNC Fertility RaleighNC 27617USA

Recent data suggest that cystic fibrosis transmembrane conductance regulator(CFTR)gene alterations negatively impact male fertility beyond obstruction.We sought to compare gene alterations,sperm retrieval rates,and intracytoplasmic sperm injection(ICSI)outcomes among men with cystic fibrosis(CF)disease and congenital bilateral absence of the vas deferens(CBAVD)only.We retrospectively evaluated all men who underwent surgical sperm retrieval at two academic,high-volume andrology centers from 2010 to 2018.Only men with documented CFTR alterations and obstructive azoospermia from either CBAVD or CF were included.Differences between groups for CFTR abnormality,sperm retrieval,and ICSI outcomes were statistically analyzed.Overall,39 patients were included with 10 in the CF and 29 in the CBAVD groups.Surgical sperm retrieval rates were significantly lower in the CF group for sperm concentration(14.8×10^(6)ml^(-1)vs 61.4×10^(6)ml^(−1),P=0.02)and total motile sperm count(2.9 million vs 11.4 million,P=0.01).This difference was only predicted by homozygous delta F508 CFTR mutations(P<0.05).The CF group also demonstrated a significantly higher rate of rescue testicular sperm extraction(70.0%vs 27.6%,P<0.03)and lower fertilization rate with ICSI(32.5%vs 68.9%,P<0.01).In conclusion,those with CF demonstrated lower sperm quality,greater difficulty with sperm retrieval,and worse ICSI outcomes compared with CBAVD-only patients.Homozygous delta F508 CFTR mutations appear to significantly impair spermatogenesis and sperm function.

关键词： congenital bilateral absence of the vas deferens cystic fibrosis intracytoplasmic sperm injection outcomes male infertility obstructive azoospermia

Men with a complete absence of normal sperm morphology exhibit high rates of success without assisted reproduction

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Asian Journal of Andrology 2017年第1期19卷 39-42页

作者： Jason R Kovac Ryan P Smith Miguel Cajipe Dolores J Lamb larry I Lipshultz Center of Reproductive Medicine and the Department of Molecular and Cellular Biology Scott Department of Urology Baylor College of Medicine Houston TX USA Department of Urology University of Virginia Charlottesville VA USA.

In couples with infertility, abnormal strict morphology of 0% normal forms （NF） is a criterion to proceed rapidly to in vitro fertilization （IVF）. Since no data currently exist, we investigated the outcomes for men with 0% NF to determine reproductive success without the use of assisted reproductive technologies （ART）. A cohort of 24 men with 0% NF were identified （2010-2013） with 27 randomly selected men with 〉4% NF as controls. Patient charts were reviewed with men contacted and administered an Institutional Review Board （IRB）-approved telephone questionnaire to ascertain outcomes. After a median follow-up time of 2.5 years, 29.2% of men with 0% NF did not require ART for their first pregnancy （controls = 55.6%, P〈 0.05）. When all pregnancies were analyzed together, men with 0% NF achieved twenty pregnancies of which 75% did not require IVF （controls - thirty pregnancies; 76.7% did not require IVF）. The average age of men and female partners was similar between men with 0% NF and 〉4% NF. All men had normal follicle-stimulating hormone （FSH）, testosterone, prolactin, sex hormone-binding globulin （SHBG）, and estradiol. Although, global semen parameters were worse in men with 0% NF, when a first pregnancy was a natural conception （NC）, 100% of men with 0% NF （n = 7/7） and 37.5% of controls in = 3/8） went on to have a subsequent pregnancy via NC. Men with 0% NF conceived without IVF in 29.2% of cases compared to 55.6% of controls. Strict morphology should not be used to predict fertilization, pregnancy, or live birth potential. In men with 0% NF, alternative modalities should be considered before immediate IVF.

关键词： conception infertility intrauterine insemination in vitro fertilization strict morphology success

An infertile male with dilated seminal vesicles due to functional obstruction

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Asian Journal of Andrology 2017年第2期19卷 256-257页

作者： Michael D Font Alexander W Pastuszak John R Case larry I Lipshult Baylor College of Medicine Houston TX 77030 USA Center for Reproductive Medicine Baylor College of Medicine Houston TX 77030 USA scott Department of Urology Baylor College of Medicine Houston TX 77030 USA Urology San Antonio San Antonio TX 78229 USA

Dear Editor, The patient is a 45-year-old male who presented to an outside clinic in 2014 for evaluation of painful ejaculation, infertility, and difficulty with urination for as long as he could remember. He reported no past significant medical or surgical history and no family history of infertility. He was given a trial of tamsulosin without improvement in his symptoms. Initial semen analysis demonstrated azoospermia.

关键词： infertile male dilated seminal vesicles due functional obstruction

Augmented reality assisted surgery： a urologic training tool

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Asian Journal of Andrology 2016年第5期18卷 732-734页

作者： Ryan M Dickey Neel Srikishen larry I Lipshultz Philippe E Spiess Rafael E Carrion Tariq S Hakky scott Department of Urology Baylor College of Medicine Houston 77030 USA University of South Florida Department of Urology Tampa 33606 USA.

Augmented reality is widely used in aeronautics and is a developing concept within surgery. In this pilot study, we developed an application for use on Google Glass optical head-mounted display to train urology residents in how to place an inflatable penile prosthesis. We use the phrase Augmented Reality Assisted Surgery to describe this novel application of augmented reality in the setting of surgery. The application demonstrates the steps of the surgical procedure of inflatable penile prosthesis placement. It also contains software that allows for detection of interest points using a camera feed from the optical head-mounted display to enable faculty to interact with residents during placement of the penile prosthesis. Urology trainees and faculty who volunteered to take part in the study were given time to experience the technology in the operative or perioperative setting and asked to complete a feedback survey. From 30 total participants using a lO-point scale, educational usefulness was rated 8.6, ease of navigation was rated 7.6, likelihood to use was rated 7.4, and distraction in operating room was rated 4.9. When stratified between trainees and faculty, trainees found the technology more educationally useful, and less distracting. Overall, 81% of the participants want this technology in their residency program, and 93% see this technology in the operating room in the future. Further development of this technology is warranted before full release, and further studies are necessary to better characterize the effectiveness of Augmented Reality Assisted Surgery in urologic surgical training.

关键词： andrology augmented reality assisted surgery Google glass inflatable penile prosthesis optical head mounted display surgical education