Z. Liang

Whole-genome sequence of a flatfish provides insights into ZW sex chromosome evolution and adaptation to a benthic lifestyle

Genetic sex determination by W and Z chromosomes has developed independently in different groups of organisms. To better understand the evolution of sex chromosomes and the plasticity of sex-determination mechanisms, we sequenced the whole genomes of a male (ZZ) and a female (ZW) half-smooth tongue sole (Cynoglossus semilaevis). In addition to insights into adaptation to a benthic lifestyle, we find that the sex chromosomes of these fish are derived from the same ancestral vertebrate protochromosome as the avian W and Z chromosomes. Notably, the same gene on the Z chromosome, dmrt1, which is the male-determining gene in birds, showed convergent evolution of features that are compatible with a similar function in tongue sole. Comparison of the relatively young tongue sole sex chromosomes with those of mammals and birds identified events that occurred during the early phase of sex-chromosome evolution. Pertinent to the current debate about heterogametic sex-chromosome decay, we find that massive gene loss occurred in the wake of sex-chromosome birth.

Epigenetic modification and inheritance in sexual reversal of fish

Environmental sex determination (ESD) occurs in divergent, phylogenetically unrelated taxa, and in some species, co-occurs with genetic sex determination (GSD) mechanisms. Although epigenetic regulation in response to environmental effects has long been proposed to be associated with ESD, a systemic analysis on epigenetic regulation of ESD is still lacking. Using half-smooth tongue sole (Cynoglossus semilaevis) as a model-a marine fish that has both ZW chromosomal GSD and temperature-dependent ESD-we investigated the role of DNA methylation in transition from GSD to ESD. Comparative analysis of the gonadal DNA methylomes of pseudomale, female, and normal male fish revealed that genes in the sex determination pathways are the major targets of substantial methylation modification during sexual reversal. Methylation modification in pseudomales is globally inherited in their ZW offspring, which can naturally develop into pseudomales without temperature incubation. Transcriptome analysis revealed that dosage compensation occurs in a restricted, methylated cytosine enriched Z chromosomal region in pseudomale testes, achieving equal expression level in normal male testes. In contrast, female-specific W chromosomal genes are suppressed in pseudomales by methylation regulation. We conclude that epigenetic regulation plays multiple crucial roles in sexual reversal of tongue sole fish. We also offer the first clues on the mechanisms behind gene dosage balancing in an organism that undergoes sexual reversal. Finally, we suggest a causal link between the bias sex chromosome assortment in the offspring of a pseudomale family and the transgenerational epigenetic inheritance of sexual reversal in tongue sole fish.

Complications of laparoscopic radical hysterectomy and lymphadenectomy for invasive cervical cancer: experience based on 317 procedures.

BackgroundThis report presents the incidence of complications and conversions during laparoscopic radical hysterectomy and lymphadenectomy performed for invasive cervical carcinoma. The data are analyzed, and strategies to help prevent future complications are discussed.MethodsFrom July 2000 to December 2005 at the authors’ institution, 317 laparoscopic radical hysterectomy and lymphadenectomy procedures for invasive cervical carcinoma were performed. The authors reviewed the database of patients who underwent laparoscopic radical hysterectomy and lymphadenectomy to examine complications and analyze factors associated with conversion to an open surgical procedure.ResultsAll but four surgical procedures were laparoscopically completed. Pelvic lymphadenectomy was performed for all the remaining 313 patients, 143 of whom underwent paraaortic lymphadenectomy. Major and minor intraoperative complications occurred for 4.4% (nxa0=xa014) of the patients. The overall conversion rate was 1.3% (nxa0=xa04), including 3 emergencies and 1 elective conversion. Seven patients had vessel injuries, five of which were repaired or treated laparoscopically. One left external iliac vein required laparotomy, and one patient underwent laparotomy to control bleeding sites. Operative cystotomies occurred in five patients, which were repaired laparoscopically. Two patients underwent laparotomy because of hypercapnia and ascending colon injury. Postoperative surgery complications occurred in 5.1% (nxa0=xa016) of the patients, including 5 patients with ureterovaginal fistula, 4 with vesicovaginal fistula requiring reoperation, 1 with ureterostenosis treated by placement of a double-J ureteral stent, and 6 with bladder dysfunctions (retention) that exhibited complete resolution within 3 to 6 months by intermittent training and catheterization.ConclusionsLaparoscopic radical hysterectomy and lymphadenectomy is becoming a routine procedure in the armamentarium of many gynecologists. Complications unique to laparoscopy do exist, but they decrease with repeated training of the procedure and gradually enriched experiences.

Detection of fetal sex chromosome aneuploidy by massively parallel sequencing of maternal plasma DNA: initial experience in a Chinese hospital

To evaluate the performance of a massively parallel sequencing (MPS)‐based test in detecting fetal sex chromosome aneuploidy (SCA) and to present a comprehensive clinical counseling protocol for SCA‐positive patients.

Laparoscopic blockage of uterine artery and myomectomy : A new method of treating symptomatic uterine leiomyomas

BackgroundThe goal of this study was to evaluate the effects of laparoscopic coagulation or blockage of the uterine arteries and myomectomy in treating symptomatic myomas.MethodsA total of 142 women with symptomatic fibroids warranting surgical treatment and wanting to retain their uteri were treated by laparoscopic coagulation or blocking of the uterine arteries and myomectomy.ResultsMost of the 142 patients had multi-myomas of the uterus, as intramural myomas (54), subserous myomas (65), and submucosal myomas (25). The number of myomas in each patient varied from 1 to 4. The size of the myomas in all patients ranged from 2 to 12 cm. In 86 cases (60.4%) the uterine wall was sutured in one layer. Average operating time was 124.2 ± 33.1 min, and average blood loss was 117.8 ± 48.6 ml. Mean postoperative hospital stay was 4.8 ± 1.2 days. All patients underwent technically successful laparoscopic coagulation or blocking of uterine arteries and myomectomy without intraoperative complications. The mean follow-up time was 16.2 months (16–26). Symptomatic improvement was achieved in all patients. Five patients experienced recurrence of myomas.ConclusionsLaparoscopic coagulation or block of the uterine arteries and myomectomy appears to be a safe, effective, and promising new method for treating symptomatic uterine myomas.

Selection of the families with high growth rate and high female proportion in half-smooth tongue sole(Cynoglossus semilaevis)

The present study aims to uncover the relationship between the phenotypic sex and genotypic sex and the growth rate of male and female half-smooth tongue sole and to select the excellent families with high female proportion.In this paper,we firstly established 22 half-smooth tongue sole families which were cultured in the same pond.Secondly,we identified the offsprings phenotypic sex and genotypic sex of 5 normal male families and 5 neo-male families.This study shows that there are significant differences not only in growth rate but also in proportion of male to female.Two fast-growing families(No.16 and No.61)whose relative weight gain rate were 0.81 g/d and 0.56 g/d and 4 relatively fast-growing families(No.21,No.28,No.57 and No.63),the relative weight gain rate ranges from 0.48 g/d to 0.53 g/d were selected;12 commonly-growing and 4 slow-growing families were selected also.The average ratios of genotypic female and phenotypic female of the 5 normal male(ZZ)families were 51.87% and 42.94%,and the ratio of genotypic female reversing to phenotypic male was 14.08%.Instead,the average genotypic female and phenotypic female ratio of the 5 neo-male(ZW)families was 49.34% and 4.45%,respectively,and the ratio of genotypic female reversing to phenotypic male was 91.41%.In the present study we found for the first time that there were significant differences in phenotypic sex ratio between different families.We also found that the genotypic females in neo-male families were more easily reversed to phenotypic males,which increased the number of phenotypic males in cultured populations.It initially showed that the families with high female proportion and fast growing rate could be selected via family selection,which could provide theories and new technical methods for the breeding and the production of high quality seeding of half-smooth tongue sole.

Robotic-Assisted Laparoscopic Nerve Sparing Radical Hysterectomy

This video shows endoscopic inguinal lymphadenectomy invulvar cancer. The patient was 72 years old, and was admitted for ‘‘vulvar excrescence for 3 month’’. On gynecologic examination, a 5*4*4cm mass located at the right labium majus pudendi and the clitoris. The pathology of lumpectomy showed it was invasive differentiated squamous cell carcinoma. And the patient underwent Radical vulvectomy and bilateral endoscopic inguinal lymphadenectomy.Thevideoshowed the left side InguinalLymphadenectomy. Conclusion: Endoscopic inguinal lymph node dissection in patients with vulvar cancer is a safe and feasible technique.