Effect of Occupational Extremely Low-Frequency Electromagnetic Field Exposure on the Thyroid Gland of Workers: A Prospective Study.

OBJECTIVE: The aim of this study was to investigate the biological effects of occupational extremely low-frequency electromagnetic field (ELF-EMF) exposure on the thyroid gland. METHODS: We conducted a prospective analysis of 85 workers (exposure group) exposed to an ELF-EMF (100 µT, 10-100 Hz) produced by the electromagnetic aircraft launch system and followed up on thyroid function indices, immunological indices, and color Doppler images for 3 years. Additionally, 116 healthy volunteers were randomly selected as controls (control group), the thyroid function of whom was compared to the exposure group. RESULTS: No significant difference was observed in thyroid function between the exposure and control groups. During the follow-up of the exposure group, the serum free triiodothyronine (FT3) level was found to slowly decrease and free thyroxine (FT4) level slowly increase with increasing exposure time. However, no significant difference was found in thyroid-stimulating hormone (TSH) over the three years, and no significant difference was observed in the FT3, FT4 and TSH levels between different exposure subgroups. Furthermore, no significant changes were observed in thyroid autoantibody levels and ultrasound images between subgroups or over time. CONCLUSION: Long-term exposure to ELF-EMF may promote thyroid secretion of T4 and inhibit deiodination of T4 to T3. ELF-EMF has no significant effect on thyroid immune function and morphology.

Influence of air quality on the selection tendency of contact lens wearers.

OBJECTIVE: This study aimed to investigate whether air quality influences ocular comfort when wearing contact lenses and the selection tendency of myopic populations who wears contact lenses. METHODS: Questionnaires were distributed to one hundred and twenty corneal contact lens wearers to understand whether the respondents would reduce or stop the use of contact lenses according to air quality and to evaluate and compare their ocular status under different air quality conditions. RESULTS: Forty-three point eight percent of the respondents were concerned about reduced oxygen permeability of contact lenses and increased contact lens-associated complications caused by the adsorption and accumulation of haze particles on the contact lens. Thirteen point four percent of the respondents stated that they would stop using contact lenses during moderate to severe air pollution and switch to glasses. Twenty-eight point six percent of respondents remarked that they would reduce the use of contact lenses depending on the situation during moderate to severe air pollution. However, this study did not find statistically significant differences in the ocular comfort while wearing contact lenses and in the eye scores of contact lens wearers under different air quality conditions. CONCLUSION: Air quality has an impact on the selection tendency of some contact lens wearers. However, whether moderate or more severe air pollution causes ocular discomfort or contact lens-associated complications in contact lens wearers awaits further investigation.

MicroRNA-134 prevents the progression of esophageal squamous cell carcinoma via the PLXNA1-mediated MAPK signalling pathway.

BACKGROUND: MicroRNAs (miRNAs) are involved in oncogenesis of esophageal squamous cell carcinoma (ESCC). miR-134 is reported to have a tumour-suppressive role but its role in ESCC is not known. The present study was designed to examine whether miR-134 inhibits ESCC development and further explored relevant underlying mechanisms. METHODS: Differentially expressed genes related to ESCC were identified from microarray gene expression profiles. Immunohistochemical staining and RT-qRCR assays identified elevated PLXNA1 expression levels and low miR-134. The relationship between miR-134 and PLXNA1 was predicted and further verified by a dual-luciferase reporter assay. The expression levels of miR-134 and PLXNA1 in ESCC cells were modified by miR-134 mimic/inhibitor and siRNA against PLXNA1, respectively. Thereafter, the expression of MAPK signalling pathway-related proteins, as well as the viability, migration, invasion, cell cycle and cell apoptosis of ESCC cells was investigated. FINDINGS: The results showed that miR-134 could block the MAPK signalling pathway by downregulating PLXNA1. When miR-134 was overexpressed or PLXNA1 was silenced, cell apoptosis was enhanced, the cell cycle was retarded, and the cell proliferation, migration and invasion were suppressed. In vivo experiments confirmed that miR-134 overexpression or PLXNA1 silencing restrained tumour growth and lymph node metastasis. INTERPRETATION: These findings demonstrate that cancer cell proliferation, migration, invasion, and tumour metastasis of ESCC can be suppressed by overexpression of miR-134 through downregulating PLXNA1, which subsequently blocks the MAPK signalling pathway. These results provide new potential targets and strategies for the treatment of ESCC.

Effect of 131I 'clear residual thyroid tissue' after surgery on the function of parathyroid gland in differentiated thyroid cancer.

Thyroid cancer is a common malignant tumor of the endocrine glands. Although surgery is the optimal treatment utilized, the disease is characterized by recurrence and metastasis. The aim of the present study was to determine the effect of iodine-131 (131I) 'clear residual thyroid tissue' following surgery on the treatment of differentiated thyroid cancer (DTC) and its effect on the function of the parathyroid gland. A total of 160 patients diagnosed with DTC, who were consecutively admitted to our Hospital between June 2012 and June 2014 and underwent total thyroidectomy or subtotal resection, were included in the present study. After three months, the patients were administered 131I 'clear residual thyroid tissue' treatment and underwent a whole body scan after 1 week to determine whether 'clear residual thyroid tissue' treatment was successful or not. The treatment was repeated within 3 months if not successful. Of the 160 patients, 24 patients had cancer metastasis (15.0%). The average dose of 131I used for the first time was 6.4+1.2 GBq and the treatment was successful in 66 cases (41.3%). The average treatment time was 2.8±0.6 therapy sessions. The results showed that, prior to and following the first treatment and at the end of the follow up, levels of the parathyroid hormone, serum calcium and phosphorus were compared, and no statistically significant difference (P>0.05) was observed. There were 5 patients with persistent hypothyroidism and 8 patients with transient hypothyroidism. The levels of thyroglobulin were significantly decreased, and the difference was statistically significant (P<0.05). A total of 48 patients (30%) with hypothyroidism were identified. In conclusion, the results have shown that DTC resection and 131I 'clear residual thyroid tissue' treatment did not significantly impair the parathyroid function, thereby improving the treatment effect.

Gastroduodenal intussusception due to gastric schwannoma treated by Billroth II distal gastrectomy: one case report.

Schwannomas are rarely observed in the gastrointestinal tract. The most common symptoms of a gastric schwannoma are abdominal pain or dyspepsia, gastrointestinal bleeding, and an abdominal mass. Many gastric schwannomas are asymptomatic and are discovered incidentally or at postmortem. The diagnosis of a schwannoma is based on immunohistochemical positivity for S-100 protein. We present a case report of a rare complication of gastric schwannoma causing gastroduodenal intussusception that was successfully managed by a Billroth II distal gastrectomy. In this rare case, the patient had intermittent, colicky abdominal pain, nausea, and vomiting for over 4 wk accompanied by a weight loss. A diagnosis of gastric intussusception was made by computed tomography. A Billroth II distal gastrectomy was then performed, and complete en bloc removal (R0 resection) was achieved. Pathology confirmed a gastric schwannoma through positive immunohistochemical staining for S-100 protein.

RhoC, vascular endothelial growth factor and microvascular density in esophageal squamous cell carcinoma.

AIM: To investigate the expression of Ras homolog (Rho)C, vascular endothelial growth factor (VEGF) and CD105 in esophageal squamous cell carcinoma. METHODS: Semi-quantitative reverse transcriptase polymerase chain reaction, in situ hybridization and immunohistochemical streptavidin-biotin- peroxidase methods were used to detect expression of RhoC mRNA and protein, and VEGF protein in 62 cases with esophageal squamous cell carcinoma, 31 cases with adjacent atypical hyperplastic tissues, and 62 cases with normal esophageal mucosa. CD105 antibody labeling was used to measure microvascular density. Expression levels were compared according to clinicopathologic and patient parameters. RESULTS: Expression of RhoC mRNA showed a positive correlation with the protein level in esophageal squamous cell carcinoma, as well as with VEGF protein levels. RhoC mRNA expression was mainly located within the cytoplasm of the tumor cells, appearing as blue to purple particles by in situ hybridization. The differences in RhoC mRNA expression in esophageal squamous cell carcinoma, adjacent atypical hyperplasia and normal esophageal mucosa were significant (P < 0.05). The relative expression of RhoC mRNA in cancer tissues with lymph node metastasis was significantly higher than in the tissues without lymph node metastasis (P < 0.05). VEGF protein expression was consistent with microvascular density (t = 25.52, P < 0.05). Positive expression of VEGF protein in esophageal squamous cell carcinoma of different histologic gradings did not differ significantly. Positive expression of VEGF protein in carcinoma tissues with deep infiltration was significantly higher than in tissues with only superficial infiltration (P < 0.05). The positive expression of VEGF protein in cancer tissues with lymph node metastasis was significantly higher than in the tissues without lymph node metastasis (P < 0.05). CONCLUSION: RhoC protein may upregulate VEGF expression, thereby promoting tumor angiogenesis. RhoC mRNA and protein expression was correlated with metastasis.

[Estimation model for daily transpiration of greenhouse muskmelon in its vegetative growth period].

For developing an estimation method of muskmelon transpiration in greenhouse, an estimation model for the daily transpiration of greenhouse muskmelon in its vegetative growth period was established, based on the greenhouse environmental parameters, muskmelon growth and development parameters, and soil moisture parameters. According to the specific environment in greenhouse, the item of aerodynamics in Penman-Monteith equation was modified, and the greenhouse environmental sub-model suitable for calculating the reference crop evapotranspiration in greenhouse was deduced. The crop factor sub-model was established with the leaf area index as independent variable, and the form of the model was linear function. The soil moisture sub-model was established with the soil relative effective moisture content as independent variable, and the form of the model was logarithmic function. With interval sowing, the model parameters were estimated and analyzed, according to the measurement data of different sowing dates in a year. The prediction accuracy of the model for sufficient irrigation and water-saving irrigation was verified, according to measurement data when the relative soil moisture content was 80%, 70%, and 60%, and the mean relative error was 11.5%, 16.2% , and 16.9% respectively. The model was a beneficial exploration for the application of Penman-Monteith equation under greenhouse environment and water-saving irrigation, having good application foreground and popularization value.

Is laboratory training essential for beginners in learning laparoscopic adrenalectomy?

The aim is to develop a staged clinical laparoscopic training program (without laboratory trainings) for beginners to perform laparoscopic adrenalectomy (LA) and to determine its safety and feasibility. Five beginners with no previous experience in adrenalectomy were randomly selected to receive the staged clinical laparoscopic training, including open retroperitoneal adrenalectomy or radical nephrectomy and mentor-initiated clinical laparoscopic training. The clinical data of the 15 LAs performed by each the trainees were collected and compared with the data from the initial 15 LAs of the mentor. All LAs were completed successfully, and no procedure required conversion to open surgery. The median operative time of the trainees was obviously less than the mentor's. The learning curve of the trainees was shorter compared with that of the mentor. The perioperative complication rate was similar between trainees and mentor. Beginners without laboratory trainings could perform LA safely and effectively after they participated in staged clinical laparoscopic training.

Ascites metabolism measurement enhanced the diagnostic value and accuracy of prognostic evaluation in 18F-FDG PET/CT studies in malignant ascites patients.

OBJECTIVE: This study aimed to evaluate the role of ascites metabolism measurement in (18)F-fluorodeoxyglucose ((18)F-FDG) PET/computed tomography (CT) for auxiliary diagnosis and prognostic evaluation of malignant ascites. MATERIALS AND METHODS: This was a retrospective study on 55 patients, including 36 with malignant ascites and 19 with benign ascites of undetermined origin, before they underwent their first (18)F-FDG PET/CT scan. The χ(2) -test was used to compare the diagnostic efficiencies among (18)F-FDG PET/CT ascites metabolism measurement, tumor localization, and ascites cytology examination. The standard uptake values of ascites and of the normal liver were measured, respectively, and their ratio, denoted as T/NT, was calculated for each patient. The receiver-operating characteristic curve was used to analyze the diagnostic efficiency of the ascites T/NT, ascites carcinoembryonic antigen, ascites CA1(25), and ascites CA(199), and the linear regression was used to analyze the relationship between the ascites T/NT and the survival time of patients. RESULTS: The metabolic level of malignant ascites was high. The sensitivity and accuracy of ascites metabolism measurement were higher than those of ascites cytology examination (χ(2) =6.98, 4.58; all P's<0.05). The specificity of ascites metabolism measurement was higher than that of (18)F-FDG PET/CT tumor localization (χ(2) =5.70, P<0.05). The T/NT value of malignant ascites (0.68 ± 0.17) was higher than that of benign ascites (0.38 ± 0.10) (t=7.21, P<0.05). The area under the receiver-operating characteristic curve of ascites T/NT was larger than those of ascites carcinoembryonic antigen, CA(125), and CA(199). There was a negative correlation between the ascites T/NT and the survival of patients with malignant ascites (r=-0.647, P<0.01). CONCLUSION: Ascites metabolism measurement has an important auxiliary diagnostic value in (18)F-FDG PET/CT for ascites patients. The ascites T/NT may be a good index for prognostic evaluation of malignant ascites.

Fast access and early ligation of the renal pedicle significantly facilitates retroperitoneal laparoscopic radical nephrectomy procedures: modified laparoscopic radical nephrectomy.

BACKGROUND: The objective of this study was to develop a modified retroperitoneal laparoscopic nephrectomy and compare its results with the previous technique. METHODS: One hundred retroperitoneal laparoscopic nephrectomies were performed from February 2007 to October 2011. The previous technique was performed in 60 cases (Group 1). The modified technique (n = 40) included fast access to the renal pedicle according to several anatomic landmarks and early ligation of renal vessels (Group 2). The mean operation time, mean blood loss, duration of hospital stay conversion rate and complication rate were compared between the groups. RESULTS: No significant differences were detected regarding mean patient age, mean body mass index, and tumor size between the two groups (P >0.05). The mean operation time was 59.5 ± 20.0 and 39.5 ± 17.5 minutes, respectively, in Groups 1 and 2 (P <0.001). The mean intraoperative blood loss was 147 ± 35 and 100 ± 25 ml, respectively, in Groups 1 and 2 (P <0.001). No significant differences were detected regarding the conversion rate and the complication rate between the two groups (P >0.05). CONCLUSIONS: Early ligature using fast access to the renal vessels during retroperitoneal laparoscopic radical nephrectomy contributed to less operation time and intraoperative blood loss compared with the previous technique. In addition, the modified technique permits the procedure to be performed following the principles of open radical nephrectomy.

[Avian diversity and bird strike risk at Fuyang Airport].

From June 2008 to January 2010, a survey of avian communities was conducted in five habitats (grassland, farmland, town, wetland, and woodland) at Fuyang Airport and its surrounding areas, with the diversity indices in different seasons and different habitats analyzed. A total of 122 avian species belonging to 15 orders and 40 families were recorded. At Fuyang Airport, the avian species number was significantly higher in summer and autumn than in winter and spring, the avian density was the highest in autumn, and the Shannon diversity index and Pielou evenness index were the highest in summer. Among the five habitats at the Airport and its surrounding areas, woodland had the greatest avian species number and density, and the woodland, wetland, and farmland had higher Shannon diversity index than grassland and town. The most dangerous avian species to the airplanes at Fuyang Airport were Passer montanus, Pycnonotus sinensis, Hirundo rustica, Columba livia f. domestica, Pica pica, Streptopelia chinensis, and Sturnus cineraceu.

Toxicity of endogenous peroxynitrite and effects of puerarin on transplanted retinal pigment epithelial sheets in the subretinal space in mice.

AIM: To evaluate the toxicity of endogeneous peroxynitrite on transplanted retinal pigment epithelial (RPE) sheets and the effect of puerarin on their survival in the C57BL/6 mice after RPE sheets have been transplanted into SD rats' subretinal space . METHODS: C57BL/6 mice eyes were used to culture RPE cells. Ninety-six SD rats were involved in the experiment. They were divided into control (block control), streptozotocin (STZ, negative control), untransplanted RPE (positive control) and transplanted RPE groups respectively. Diabetes was induced in SD rats by intra-peritoneal STZ injection in the latter three groups. Saline was injected into the subretinal space of 24 SD rats in the untransplanted RPE group and primary RPE sheets were injected into the subretinal space of 24 SD rats in the transplanted RPE group. Puerarin (45mg/kg) was administrated into both untransplanted RPE and transplanted RPE groups of diabetic rats through intra-peritoneal injection route after RPE sheets transplantation. At 20, 40, 60 days after surgery, Western blotting analysis, DNA ladder and RT-PCR were used for determining the differences in expression of nitrotyrosine (NT, the foot print of peroxynitrite ), apoptosis and iNOS mRNA in the control, STZ, untransplanted RPE and transplanted RPE groups respectively. HE staining was used for determining the RPE survival in the subretinal space of the transplanted RPE group. RESULTS: Apoptosis and expression of NT and iNOS mRNA were observed in STZ, untransplanted RPE and transplanted RPE groups, but were delayed in untransplanted RPE and transplanted RPE groups in a time-dependent manner compared with control and STZ groups (P<0.01). There were no differences between the two groups (P>0.01). NT, DNA ladder, iNOS mRNA were down-regulated, which were associated with the decrease of expression of peroxynitrite. Numerous pigmented cells emerged and increased in number in the subretinal space during the 60-day observation period after transplantation. On day 20, heavily pigmented cells were visible at the transplant site; On day 40, monolayer and multilayered transplant was visible in the subretinal space; On day 60, heavily pigmented monolayer and multilayered transplants with round apical profile were present along Bruch's membrane. CONCLUSION: Puerarin increased the 60-day survival of C57BL/6 mice RPE xenografts in the SD rats' subretinal space, which may be related to its direct inhibition of apoptosis of RPE cells and antagnism of damage of peroxynitrite to RPE cells.

[Prokaryotic expression, polyclonal antibody preparation and subcellular localization of CIB].

AIM: To construct the prokaryotic expression vector pET32a-CIB, prepare the specific polyclonal antibody against CIB and study the subcellular localization of CIB. METHODS: CIB was amplified by RT-PCR from human brain tissue and cloned into prokaryotic expression vector pET32a-CIB. The CIB fusion protein was expressed in BL21 (DE3)/pET system and identified by SDS-PAGE. The mice were immunized with the polyacrylamide gel particles containing the CIB fusion protein for polyclonal antibody preparation. The antibody was purified by affinity chromatographic column matrix coupled with protein G, antigen respectively and then identified by Western blot and immunohistochemistry. RESULTS: The protein of CIB was obtained by recombination expression. The specificity of polyclonal antibody was obtained by immunizing BALB/c mice with polyacrylamide gel particles containing the fusion protein of CIB and purification. The results of immunohistochemistry demonstrated that CIB was localized predominantly in the cytoplasm of SHG44 and Hhu7 cells. CONCLUSION: The protein of CIB has been cloned and expressed successfully. The specific polyclonal antibody against the protein of CIB has been obtained, which can be used for further research into the function of CIB.

Correlation of matrix metalloproteinase suppressor genes RECK, VEGF, and CD105 with angiogenesis and biological behavior in esophageal squamous cell carcinoma.

AIM: To explore the expression of reversion inducing cysteine-rich protein with Kazal motifs (RECK), vascular endothelial growth factor (VEGF) and endoglin (CD105) protein and its correlation with occurrence, development, invasion and metastasis in esophageal squamous cell carcinoma (ESCC). METHODS: Streptavidin-peroxidase (SP) immunohisto-chemistry was used to detect expression of RECK and VEGF in 62 cases of ESCC, 31 cases of adjacent atypical hyperplastic epithelium and 62 cases of normal esophageal epithelium. CD105 Mb was used to assess microvessel density (MVD). RESULTS: The expression of RECK was closely correlated with histological grade, infiltrative depth and lymphatic metastasis in ESCC (P < 0.05). The expression of RECK decreased during cancer development: normal esophageal epithelium (85.5%, 53/62), adjacent atypical hyperplastic epithelium (71.0%, 22/31), and carcinoma (59.7%, 37/62). There was a significant difference among the groups (P < 0.05). The expression of VEGF protein was closely correlated with infiltrative depth and lymphatic metastasis in ESCC (P < 0.05). The expression of VEGF protein increased during cancer development: normal esophageal epithelium (29.0%, 18/62), adjacent atypical hyperplastic epithelium (54.8%, 17/31), and carcinoma (67.7%, 42/62). There was a significant difference among the groups (P < 0.05). MVDCD105 increased in accordance with histological grade, but there was no significant difference (grade I, 36.92 +/- 10.85; grade II, 37.65 +/- 9.50; and grade III, 38.06 +/- 12.19). The MVDCD105 was closely correlated with infiltration and lymphatic metastasis in ESCC (P < 0.05). The expression of RECK was inversely correlated with the expression of VEGF and CD105. CONCLUSION: RECK, VEGF and CD105 play important roles in the infiltration, metastasis and carcinogenesis in esophageal carcinoma. Angiogenesis in ESCC may be promoted by over-expression of CD105.

Mechanical and superhydrophobic stabilities of two-scale surfacial structure of lotus leaves.

To understand why lotus leaf surfaces have a two-scale structure, we explore in this paper two stability mechanisms. One is the stability of the Cassie-Baxter wetting mode that generates the superhydrophobicity. A recent quantitative study (Zheng et al., Langmuir 2005, 21, 12207) showed that the larger the slenderness ratio of the surface structures was, the more stable the Cassie-Baxter wetting mode would be. On the other hand, it is well-known that more slender surface structures can only sustain lower critical water pressures for structure buckling, or Euler instability, while in the natural environments, the water pressure impacting on the lotus surface can reach a fairly high value (105 Pa in a heavy rain). Our analysis reveals that the two-scale structure of the lotus leaf surfaces is necessary for keeping both the structure and the superhydrophobicity stable. Furthermore, we find that the water-air interfacial tension makes the slender surface structure more instable and the two-scale structure a necessity.

[The relationship between intrathyroidal dendritic cells and humoral immune disorder in Graves' disease].

OBJECTIVE: To investigate the relationship between intrathyroidal dendritic cells and humoral immune disorder in Graves' disease. METHODS: With the use of S-100 protein antibodies and the help of SP immunohistochemical method, the number and distribution of S-100 protein positive dendritic cells were observed in thyroid glands from 34 patients with Graves' disease and 5 controls. Serum thyroid stimulating antibodies (TSAb) before operation were measured with human embryo-kidney cells expressing the recombinant thyrotrophin receptor. The correlation between the infiltrating degree of intrathyroidal dendritic cells and the values of serum TSAb was analyzed in patients with Graves' disease. RESULTS: In normal thyroid glands, no S-100 protein positive dendritic cells were found. Dendritic cells were seen in all observed thyroid glands from patients with Graves' disease. Most of the dendritic cells were seen in close contact with the adjacent thyroid epithelial cells or infiltrating lymphocytes. The infiltrating degree of intrathyroidal dendritic cells in Graves' disease correlated closely with the values of serum TSAb (r = 0.4461, P < 0.01). CONCLUSION: It is suggested that the intrathyroidal dendritic cells have a close relation with humoral immune disorder and play an important role in the initiation and/or maintenance of thyroid autoimmune reaction in Graves' disease.