[Preliminary experience with transoral endoscopic thyroidectomy via vestibular approach: a report of 150 cases in a single center]

Objective: To summarize the preliminary experience with transoral endoscopic thyroidectomy via vestibular approach (TOETVA). Methods: A total of 150 consecutive patients with thyroid disease underwent TOETVA from November 2014 to February 2017 at Department of Thyroid Surgery, the Second Affiliated Hospital of Zhejiang University School of Medicine. The patients were comprised of 138 females and 12 males. The mean age of the patients was (31.7±7.6) years (ranging from 15 to 51 years). There were 108 patients of differential thyroid carcinoma (T1 or T2 ≤3 cm, cN0 or cN1a, M0) and 42 patients of benign thyroid disease (solid nodule ≤6 cm). The criteria analyzed were clinicopathologic characteristics, types of operation, operation time, complications and results of follow-up. Results: Two cases were converted into open surgery due to an incredible unexpected tumor size and tracheal invasion, respectively. One hundred and three patients with papillary carcinoma underwent transoral central neck dissection (CND), with the mean operation time of (146±34) minutes for hemithyroidectomy with CND, and (187±36) minutes for total or near total thyroidectomy with CND. The mean number of lymph node yields was 8.2±4.7, and the lymph node metastasis rate was 41.7% (43/103). Regarding postoperative complications, transient hoarseness occurred in 3 patients, and permanent recurrent laryngeal nerve occurred in 2 patients. One patient had local infection or transient mental nerve palsy. Transient hypocalcemia occurred in 31.8% of 22 patients who underwent total, near-total, or subtotalthyroidectomy, and no permanent hypocalcemia was registered. Mean hospital stay after operation was (3.5±0.6) days (ranging from 2 to 5 days). Mean follow-up period was (11.5±7.8) months (ranging from 1 to 28 months), no recurrence or metastasis occurred. Conclusions: TOETVA is feasible and safe for strictly selective patients. It brings perfect cosmetic effect. Long-term follow-up and further study is needed to assess its curative effect.

[The predictive accuracy of fine needle aspiration and BRAF V600E mutation in diagnosis of papillary thyroid carcinoma]

Objective: To evaluate the predictive accuracy of fine needle aspiration (FNA) and BRAF V600E mutation in distinguishing papillary thyroid carcinoma and other thyroid nodules. Methods: This retrospective cohort study included 93 patients with papillary thyroid carcinoma who treated at Department of Thyroid Surgery, the Second Affiliated Hospital of Zhejiang University, College of Medicine from September 2016 to May 2018. There were 21 males and 72 females with age of (43.2±11.3) years (range: 19 to 67 years). All the patients got the examinations of FNA and BRAF V600E mutation by Amplification Refractory Mutation System, and subsequently underwent thyroid surgeries. The results of cytopathology, frozen section and pathology were collected and analyzed. The predictive accuracy of FNA cytology and BRAF V600E mutation was calculated. Results: In the 93 collected cases, 91 were diagnosed as papillary thyroid carcinoma postoperation, and the accurate predictive rate was 97.8%. Subgroup analysis was performed according to Bethesda System, the predictive rates were: unsatisfactory (Ⅰ) 6/6, benign (Ⅱ) 0/0, atypia of undetermined significance or follicular lesion of undetermined significance (Ⅲ) 16/17, follicular neoplasm or suspicious for follicular neoplasm (Ⅳ) 97.2% (35/36), suspicious for malignancy (Ⅴ) 100% (28/28), and malignant (Ⅵ) 6/6, respectively. Conclusion: Thyroid nodules with BRAF V600E mutation can be strongly speculated as papillary thyroid carcinoma.

[A comparative study of endoscopic and traditional open surgery in the treatment of papillary thyroid carcinoma]

Objective: To evaluate the feasibility, safety and efficacy of endoscopic thyroidectomy in the treatment of papillary thyroid carcinoma through clinical follow-up. Methods: Patients who underwent total thyroidectomy and had a final pathologic diagnosis of papillary thyroid carcinoma at Department of Thyroid Surgery, Second Affiliated Hospital, Zhejiang University School of Medicine between February 2013 and April 2014 were enrolled in this study; those who had family history of thyroid cancer or a history of radiation of the neck area were excluded. There were 78 male and 228 female pantients, aging from 20 to 77 years with an age of (45.6±12.7) years. The patients were then divided into two groups: endoscopic surgery group (n=48) and traditional open surgery group (n=258). The clinical and pathological features and long-term follow-up data were collected and analyzed. The differences in surgical trauma, completeness, postoperative complications, and recurrence and metastasis risks between the two groups were compared by t test, rank-sum test, χ(2) test or Fisher exact test. Results: Compared to open surgery, endoscopic thyroidectomy had significant longer surgical time ((3.2±0.6) hours vs. (1.6±0.5) hours, t=17.904, P=0.000), two cases converted to open surgery because of tumor invasion of the recurrent laryngeal nerve, and one because of a false negative cell biology preopertively. The two groups showed no significant difference in surgical trauma which was measured by bleeding, white blood cell, C reactive protein, drainage, and et al. During follow up, the two groups had no significant difference in rate of Tg<1 μg/L (97.9% vs. 91.9%, P=0.220). Recurrent rate showed no significant difference (4.1% in endoscopic group vs. 3.1% in open group, P=0.665) between the two groups after follow-up of (40.8±4.7) months. Recurrent time were either not significantly different ((23.5±21.9) months vs. (20.0±14.6) months, P=0.785) between the two groups. Conclusion: Compared with conventional open thyroidecomy, endoscopic thyroidectomy has the same safety, surgical completeness and long-term therapeutic effect.

Effect of estradiol and bisphenol A on human hepatoblastoma cell viability and telomerase activity

Sex hormones from environmental and physiological sources might play a major role in the pathogenesis of hepatoblastoma in children. This study investigated the effects of estradiol and bisphenol A on the proliferation and telomerase activity of human hepatoblastoma HepG2 cells. The cells were divided into 6 treatment groups: control, bisphenol A, estradiol, anti-estrogen ICI 182,780 (hereinafter ICI), bisphenol A+ICI, and estradiol+ICI. Cell proliferation was measured based on average absorbance using the Cell Counting-8 assay. The cell cycle distribution and apoptotic index were determined by flow cytometry. Telomerase activity was detected by polymerase chain reaction and a telomeric repeat amplification protocol assay. A higher cell density was observed in bisphenol A (P<0.01) and estradiol (P<0.05) groups compared with the control group. Cell numbers in S and G2/M phases after treatment for 48 h were higher (P<0.05), while the apoptotic index was lower (P<0.05) and telomerase activities at 48 and 72 h (P<0.05) were higher in these groups than in the control group. The cell density was also higher in bisphenol A+ICI (P<0.01) and estradiol+ICI (P<0.05) groups compared with the ICI group. Furthermore, cell numbers were increased in S and G2/M phases (P<0.05), while the apoptotic index was lower (P<0.05) and telomerase activities at 48 and 72 h were higher (P<0.05) in these groups than in the ICI group. Therefore, bisphenol A and estradiol promote HepG2 cell proliferation in vitro by inhibition of apoptosis and stimulation of telomerase activity via an estrogen receptor-dependent pathway.

Detection of Helicobacter in the fecal material of the endangered Yangtze finless porpoise Neophocaena phocaenoides asiaeorientalis

In animals, infection by the Epsilonproteobacteria Helicobacter spp. and H. cetorum is widespread. It has been suggested that H. cetorum may cause gastritis in cetaceans. The aim of our study was to investigate the presence of Helicobacter spp. in the fecal material of the endangered Yangtze finless porpoise Neophocaena phocaenoides asiaeorientalis. The fecal material of 12 porpoises living in the wild in Poyang Lake and 1 porpoise living in captivity at the Wuhan Baiji Dolphinarium were examined by PCR for the presence of Helicobacter spp. The fecal material of 8 of 12 wild porpoises and the captive porpoise were positive for Helicobacter spp. as determined by PCR using Helicobacter-specific primers, which target the 16S rRNA gene. A 16S rRNA clone library was then prepared from 1 sample isolated from a female porpoise living in the wild. DNA sequence analysis from 3 of the clones showed 98 to 99% identity to the H. cetorum 16S rRNA gene. These results demonstrate the prevalence of Helicobacter spp. and H. cetorum in endangered freshwater finless porpoises.

Formation of subwavelength periodic structures on tungsten induced by ultrashort laser pulses

The evolution of surface morphology of tungsten irradiated by single-beam femtosecond laser pulses is investigated. Ripplelike periodic structures have been observed. The period of these ripples does not show a simple relation to the wavelength and angle of incidence. The orientation of ripples is aligned perpendicularly to the direction of polarization for linearly polarized light. Surprisingly, we find that the alignment of the ripple structure turned left or right by 45 degrees with respect to the incident plane when using right and left circularly polarized light, respectively. The period of the ripple can be controlled by the pulse energy, the number of pulses, and the incident angle. We find a clear threshold for the formation as a function of pulse energy and number of pulses. The mechanism for the ripple formation is discussed, as well as potential applications in large-area structuring of metals.

Cloning and characterization of the mouse alpha globin cluster and a new hypervariable marker

A 95-kb region of the mouse genome spanning the entire alpha-globin gene cluster was isolated as overlapping cosmid clones and characterized. In addition to the embryonic (zeta) and adult (alpha) genes, the cloned contig contains the complete N-methylpurine-DNA glycosylase (MPG) gene, the alpha-globin-positive regulatory element (mHS-26), and a previously unidentified hypervariable region (named the mouse alpha-HVR). In mice, the distance between the MPG gene and mHS-26 is approximately 18 kb; between the mHS-26 and the zeta-gene, approximately 26 kb; from the zeta-gene to the 5' end of the alpha-gene, approximately 16 kb; and the two alpha-genes are separated by approximately 12 kb. In human, the corresponding distances are approximately 27 kb, approximately 40 kb, approximately 19 kb, and approximately 3 kb respectively. The alpha-HVR is located approximately 18 kb upstream of the mouse zeta-globin gene transcription start site and contains a variable copy number tandem repeat (VNTR) array of a 35-bp sequence rich in (G+C) content. The unit sequence of the HVR shares the short core sequence with the HVRs identified in the human alpha-gene cluster. Thus, this HVR may be a valuable evolutionary marker, as well as a useful genetic marker for the mouse.

[The expression of alpha 1-inhibitor 3 gene and some changes of its structure in rat hepatomas]

The expression and structure of alpha 1-inhibitor 3 (alpha 1-I3) gene were investigated in 16 primary rat hepatomas induced by diethylnitrosamine. In most tumor samples (75%, 12/16), the expression of alpha 1-I3 gene manifested markedly diminished or undetectable level of alpha 1-I3 mRNA. Further study indicated that the abnormal expression of alpha 1-I3 gene in the hepatomas examined might be due to, at least in part, the gene hypermethylation, insertion of repeat sequence(s) or base substitutions at the recognition sequences of some restriction endonucleases which caused certain alteration in the gene structure. The significance of alpha 1-I3 as an endogenous antitumor factor in hepatocarcinogenesis was also discussed.

[Study on ATPase of tumor cells--I. A comparison of several ATPase activities]

The activities of several ATPases of the ascitic hepatoma cells in mice were compared. The activities of the total ATPase and mitochondrial Mg++-ATPase in normal liver cells were 50% and 140% higher than those in the hepatoma cells (P less than 0.001). However, the Na+, K+-ATPase activity in hepatoma cells was 170% higher than that in normal liver cells (P less than 0.01). The proportion of the activities of mitochondrial Mg++-ATPase, as well as Na+, K+-ATPase to their respective total ATPase in hepatoma cells was in disorder. The relation between the changes of the activity of different ATPases, their proportion and the abnormal metabolism as well as some characteristics of tumor cells are discussed.