[Comprehensive assessment of mismatch repair and microsatellite instability status in molecular classification of endometrial carcinoma].

Objective: To explore the concordance and causes of different mismatch repair (MMR) and microsatellite instability (MSI) detection results in endometrial carcinoma (EC) molecular typing. Methods: A total of 214 EC patients diagnosed from January 2021 to April 2023 were selected at the Department of Pathology, Peking University Third Hospital. The immunohistochemistry (IHC) results of MMR protein were reviewed. Tumor specific somatic mutations, MMR germline mutations, microsatellite scores and tumor mutation burden (TMB) were detected by next-generation sequencing (NGS) with multi-gene panel. Methylation-specific PCR was used to detect the methylation status of MLH1 gene promoter in cases with deficient MLH1 protein expression. In cases with discrepant results between MMR-IHC and MSI-NGS, the MSI status was detected again by PCR (MSI-PCR), and the molecular typing was determined by combining the results of TMB and MLH1 gene promoter methylation. Results: (1) In this study, there were 22 cases of POLE gene mutation subtype, 55 cases of mismatch repair deficient (MMR-d) subtype, 29 cases of p53 abnormal subtype, and 108 cases of no specific molecular profile (NSMP). The median age at diagnosis of MMR-d subtype (54 years old) and the proportion of aggressive histological types (40.0%, 22/55) were higher than those of NSMP subtype [50 years old and 12.0% (13/108) respectively; all P<0.05]. (2) Among 214 patients, MMR-IHC test showed that 153 patients were mismatch repair proficient (MMR-p), 49 patients were MMR-d, and 12 patients were difficult to evaluate directly. MSI-NGS showed that 164 patients were microsatellite stable (MSS; equal to MMR-p), 48 patients were high microsatellite instability (MSI-H; equal to MMR-d), and 2 patients had no MSI-NGS results because the effective sequencing depth did not meet the quality control. The overall concordance between MMR-IHC and MSI-NGS was 94.3% (200/212). All the 12 discrepant cases were MMR-d or subclonal loss of MMR protein by IHC, but MSS by NGS. Among them, 10 cases were loss or subclonal loss of MLH1 and (or) PMS2 protein. Three discrepant cases were classified as POLE gene mutation subtype. In the remaining 9 cases, 5 cases and 3 cases were confirmed as MSI-H and low microsatellite instability (MSI-L) respectively by MSI-PCR, 6 cases were detected as MLH1 gene promoter methylation and 7 cases demonstrated high TMB (>10 mutations/Mb). These 9 cases were classified as MMR-d EC. (3) Lynch syndrome was diagnosed in 27.3% (15/55) of all 55 MMR-d EC cases, and the TMB of EC with MSH2 and (or) MSH6 protein loss or associated with Lynch syndrome [(71.0±26.2) and (71.5±20.1) mutations/Mb respectively] were significantly higher than those of EC with MLH1 and (or) PMS2 loss or sporadic MMR-d EC [(38.2±19.1) and (41.9±24.3) mutations/Mb respectively, all P<0.01]. The top 10 most frequently mutated genes in MMR-d EC were PTEN (85.5%, 47/55), ARID1A (80.0%, 44/55), PIK3CA (69.1%, 38/55), KMT2B (60.0%, 33/55), CTCF (45.5%, 25/55), RNF43 (40.0%, 22/55), KRAS (36.4%, 20/55), CREBBP (34.5%, 19/55), LRP1B (32.7%, 18/55) and BRCA2 (32.7%, 18/55). Concurrent PTEN, ARID1A and PIK3CA gene mutations were found in 50.9% (28/55) of MMR-d EC patients. Conclusions: The concordance of MMR-IHC and MSI-NGS in EC is relatively high.The discordance in a few MMR-d EC are mostly found in cases with MLH1 and (or) PMS2 protein loss or MMR protein subclonal staining caused by MLH1 gene promoter hypermethylation. In order to provide accurate molecular typing for EC patients, MLH1 gene methylation, MSI-PCR, MMR gene germline mutation and TMB should be combined to comprehensively evaluate MMR and MSI status.

[Fumarate hydratase deficient uterine leiomyoma: a clinicopathological and molecular analysis of 80 cases].

Objective: To investigate the clinicopathologic and molecular characteristics of fumarate hydratase (FH) deficient uterine leiomyoma. Methods: Eighty cases of FH deficient uterine leiomyoma were diagnosed from April 2018 to September 2022 in Department of Pathology, Peking University Third Hospital. Sanger sequencing of FH gene exons (exon 1-10) were performed on tumor tissues and matched non-tumor tissues/peripheral blood for all cases. FH immunohistochemistry were performed in 74 cases; S-(2-succino)-cysteine (2SC) were also detected by immunohistochemistry in five cases. Results: Patients' age ranged from 18 to 54 (36.0±7.5) years, with more than 60% exhibiting clinical symptoms of multiple and large leiomyomas (the median diameter was 70 mm). More than four histologic features, including staghorn vasculature, alveolar-pattern edema, bizarre nuclei, oval nuclei arranged in chains, prominent eosinophilic nucleoli with perinucleolar haloes and eosinophilic intracytoplasmic globules were observed in 98.5% (67/68) patients. The immunohistochemical sensitivity of FH and 2SC were 97.3% and 100%, respectively. Based on the Sanger sequencing results, the cases were divided into germline variant group (31 cases), somatic variant group (29 cases) and no variant group (20 cases). Sixty-nine percent (20/29) of the patients with FH germline variation had clear family history. Conclusions: Clinical features, histological morphology, FH and 2SC immunohistochemistry and Sanger sequencing have their own significance and limitations in differential diagnosis of FH deficient uterine leiomyoma. In clinical practice, the above information should be fully integrated and studied for accurate pathologic diagnosis and selection of patients with FH germline variation.

[Activation of JAK/STAT in ovarian high-grade serous cancers and its prognostic significance].

OBJECTIVE: The activation of Janus kinase (JAK) and signal transducers and activators of transcription (STAT) plays an important role in the prognosis and targeted therapy of ovarian high-grade serous carcinoma (HGSC). Utilizing simple and practicable technique, this study aimed to evaluate the activation of JAK/STAT signaling pathway in ovarian HGSC patients, and investigated the correlation between the activation of JAK/STAT signaling pathway and the prognosis of the HGSC patients. METHODS: We performed immunohistochemistry of phosphorylated STAT3 (pSTAT3) and phosphorylated STAT5 (pSTAT5) on paraffin imbedded slides of 73 ovarian HGSC patients, and evaluated the expression level and range of both markers. According to the grading score of the immunostaining of pSTAT3 and pSTAT5, we divided the 73 ovarian HGSC cases into STAT3 low/high expression and STAT5 low/high expression groups, and analyzed the prognosis of the patients in different groups, in order to explore the relationship between the expression of pSTAT3 and pSTAT5 proteins and the prognosis of the HGSC patients. RESULTS: Some of the ovarian HGSC cases showed high expression of pSTAT3 and pSTAT5 protein level, which was related to the poorer prognosis of the HGSC patients. There was a significant difference in the expression level of pSTAT3 and pSTAT5 between the patients with better prognosis (survival time ≥3 years) and poorer prognosis (survival time < 3 years). The patients with higher protein expression of pSTAT3, pSTAT5 or both markers might have poorer prognosis, with significant shorter progression-free survival time and overall survival time (P < 0.001). CONCLUSION: Immunostaining of pSTAT3 and pSTAT5 proteins might be helpful to evaluate and predict the prognosis of the ovarian HGSC patients, and to identify the patients who might have higher chances to respond to the STAT inhibitors and anti-angiogenesis therapy.

[Uterine POLE mutant endometrioid carcinoma combined with human papilloma virus-associated cervical adenocarcinoma: A case report and literature review].

Independent primary uterine and cervical adenocarcinoma are rare and difficult to identify their origins, which makes treatment decision difficult. A 46-year-old female with endometrioid carcinoma and adenocarcinoma, human papilloma virus (HPV)-associated of the uterine cervix was reported. The patient presented with increased menstrual flow, contact bleeding and watery leucorrhea for more than one year, and the imaging findings showed abnormal uterine morphology, irregular margins, and multiple abnormal signals in uterine cavity and myometrium, which suggested multiple leiomyomas of the uterus. The signal intensity in the right muscle layer was markedly enhanced, suggesting a smooth muscle tumor of uncertain malignant potential. A large number of cystic hypointensity was seen in the cervix, and multiple cysts were considered. The initial preoperative diagnosis was multiple leiomyoma of the uterus, and a hysterectomy operation was planned. During the operation, the uterus was sent for frozen sections. There was a mass in the endometrium of the fundus, with a soft grayish-red cut surface and a clear border with the myometrium, and there was a grayish-white nodule in the cervix with a hard grayish-white cut surface. The two masses were well demarcated from each other, and the distance between them was 30 mm. The result of the frozen sections indicated the malignant tumor of the endometrium, and the extended hysterectomy+pelvic lymphadenectomy+partial resection of the greater omentum was performed. After the operation, the paraffin sections were sent to the Department of Pathology of the Peking University Third Hospital for histochemistry, POLE gene sequencing and HPV RNAscope tests, and the final diagnosis was a synchronous endometrioid carcinoma (POLE-mutant according to the WHO classification) and an adenocarcinoma, HPV-associated of the uterine cervix. Now the patient had been treated with 2 cycles of chemotherapy and her condition was fine. Through the analysis of the histological, immunohistochemical and molecular detection results of this case, the importance of applying HPV RNAscope and TCGA molecular typing in the diagnosis of cervical adenocarcinomas and endometrial carcinomas was emphasized. At the same time, gynecologists should not blindly rely on intraoperative frozen sections, and should pay attention to preoperative pathological examination, and make appropriate operation methods according to the results in order to prevent passivity in the surgery.

[Complications of Da Vinci robot thyroid surgery by bilateral axillo-breast approach].

Objective: To evaluate the complications of Da Vinci robotic thyroid surgery by bilateral axillo-breast approach. Methods: A retrospective analysis of complications was conducted on 1, 198 cases of Da Vinci robotic thyroid surgery by bilateral axillo-breast approach of the 960 th Hospital of the People's Liberation Army from February 2014 to March 2020. There were 263 men and 935 women, age ranged from 9 to 68 years old, and included 288 benign lesions and 910 malignancies according to preoperative imaging examination, FNAC, and intraoperative frozen pathology. Results: Surgical complications occurred in 187 (15.61%) patients, including 10 cases of temporary larynx nerve injury (0.83%), 1 case of permanent larynx nerve injury (0.08%), and 152 cases of temporary hypoparathyroidism (12.69%), no permanent hypoparathyroidism, 1 case of hypoglossal injury (0.08%), 2 cases of facial nerve jaw branch damage (0.17%), 2 cases of trachea injury (0.17%), no esophagus damage, 5 cases of celiac leakage (0.42%), 3 cases of neck skin adhesion (0.25%), 2 cases of subdermal bleeding (0.17%), 2 cases of skin burns (0.17%), 5 cases of hematoma (0.42%), 1 case of cephalic artery rupture (0.08%), 1 case of jugular vein rupture (0.08%), no tumor cultivation, no arm plex nerve, accessory nerve or phrenic nerve damage. Conclusion: Da Vinci robot thyroid surgery by bilateral axillo-breast approach is safe, with less severe complications.

[Molecular pathological diagnosis of twin pregnancy with complicated genetical characteristics].

Objective: To investigate the molecular pathological diagnostic strategy of twin pregnancy(TP) with complex genetic characteristics, using p57 immunohistochemistry and short tandem repeat (STR) genotyping. Methods: Ten cases of TP with suspected hydatidiform mole(HM) according to pathological morphology were collected in Peking University Third Hospital from 2015 to 2019, and were subject to p57 immunohistochemistry, STR genotyping and follow-up. Results: The age of ten patients ranged 23 to 36 years, with an average of 29.5 years. Seven patients accepted assisted reproductive techniques in this conception. Three patients with "divergent" p57 staining pattern were diagnosed as TP with complete HM by STR, in which one had a persistent trophoblastic disease. The villi of five patients were consistently positive for p57, but the genotyping result was polyploid and suspicious as TP. Four of them showed excessive paternal alleles at more than 40% of the loci, suggesting that concomitant partial moles could not be excluded. One patient was diagnosed as TP without HM according to the maternal allelic predominance at all loci in villi. Two patients with p57 "divergent" and "discordant" staining villi were genotyped as TP with mosaic conception. Conclusions: The correct identification of p57 staining pattern and accurate interpretation of STR genotyping results are important in diagnosing TP. It may assist pathologists in making a definite or likely diagnosis of TP with complex genetic features to fulfill clinical triage strategies and contribute to formulate a reasonable follow-up approach.

[Clinicopathological study of SET subtype of ovarian high-grade serous carcinoma].

Objective: To investigate the clinicopathological characteristics and significance of solid, endometrioid and transitional (SET) ovarian high-grade serous carcinoma (HGSC). Methods: A total of 408 cases of ovarian HGSC admitted to Peking University People's Hospital from January 2011 to September 2016 were collected. (1) According to the proportion of tumors with SET form in all tumors, they were divided into three groups: HGSC-classic group (<25%), HGSC-SET Ⅰ (25%-50%) and HGSC-SET Ⅱ (>50%) group. The clinical and pathological characteristics of three groups of ovarian HGSC patients were compared respectively. (2) According to the growth pattern, that was, the proportion of pushing/expanding invasive tumors in the whole pelvic disseminated tumors of pelvic disseminated tumors, the three groups were divided into four subgroups: group A (0-25%), group B (26%-50%), group C (51%-75%) and group D (>75%). Differences in progression-free survival (PFS) among the four subgroups in each group were compared respectively. Results: The median age of 408 cases with ovarian HGSC was 63.3 years (47-78 years), including 152 cases premenopausal and 256 cases postmenopausal. Among 408 cases of ovarian HGSC, 290 cases were in HGSC-classic group, 91 cases in HGSC-SET Ⅰ and 27 cases in HGSC-SET Ⅱ group. (1) There were significant differences in age, proportion of menopausal patients, tumor necrosis (including map necrosis or acne necrosis), response rate to primary chemotherapy, 5-year mortality rate and PFS between HGSC-SET Ⅰ and HGSC-SET Ⅱ (P<0.05). There was no significant difference among the above indexes between HGSC-SET Ⅰ and HGSC-SET Ⅱ (P>0.05). In HGSC-classic group, HGSC-SET Ⅰ and HGSC-SET Ⅱ, the proportion of family members or patients with history of epithelial ovarian cancer or breast cancer increased in turn, and the detection rate of serous tutal intraepithelial carcinoma (STIC) in fallopian tube tissue decreased in turn. There were significant differences between the two groups (P<0.05). (2) In HGSC-classic group, there were 147 cases in group A, 124 cases in group B and 19 cases in group C (0 case in group D), with median PFS of 17.4, 17.7 and 16.5 months respectively (P<0.05); 10, 6, 29 and 46 cases in group A, B, C and D in HGSC-SET Ⅰ, with median PFS of 9.6, 12.7, 30.1 months and 39.0 months respectively, which there were significant difference among group A and C and D (all P<0.05); among group B, C and D group in HGSC-SET Ⅱ, there were respectively 3, 12 and 12 cases (0 case in group A), and the median PFS was 13.5, 34.2 and 47.8 months (P<0.05). PFS was positively correlated with the increase of push/expansive infiltration ratio. Conclusions: The detection rate of STIC in ovarian HGSC patients with SET is higher, the effect of primary chemotherapy is better, and PFS is prolonged. PFS was significantly prolonged in patients with pelvic disseminated tumors of HGSC-SET, the infiltration of which were predominated by pushing or expanding boarder.

[Clinical application of TCGA molecular classification in endometrial endometrioid carcinoma].

Objective: To explore molecular characteristics of endometrial endometrioid cancer according to The Cancer Genome Atlas (TCGA) based molecular classification of endometrial carcinomas and to confirm simple and clinically applicable surrogate methodologies in pathological practice. Methods: Two hundred and twenty-eight cases of endometrial endometroid adenocarcinomas (EnACs) collected from August 2001 to August 2017 from Peking University Health Science Center, Peking University Third Hospital were molecularly categorized by using Sanger sequencing for the exonuclease domain mutations (EDM) of POLE, and by immunohistochemistry for p53 and mismatch repair (MMR) proteins. The cohort was classified into polymerase-E exonuclease domain mutation (POLE EDM), mismatch repair deficiency (MMR-D), p53 abnormal (p53-abn) and p53 wild type (p53-wt) groups. The correlation between molecular subgroups and the clinical-pathological features including prognosis were analyzed. Results: The cohort was distributed as follows: 11(4.8%) POLE EDM, 47(20.6%) MMR-D, 9(4.0%) p53-abn and 161(70.6%) p53-wt. p53-wt subgroup patients demonstrated significantly higher lymph node metastasis (P=0.011) and more advanced stage (P=0.036) than those of somatic hypermutation group cases (POLE EDM and MMR-D). In the FIGO grade 2-3 EnACs cohort, TCGA molecular subtyping was significantly correlated with progression-free survival and overall survival (P=0.043). POLE EDM subgroup had the best survival, while p53-abn subgroup had the worst. Conclusions: Identification of POLE EDM and MMR-D subgroups provides independent and highly valuable prognostic information beyond established histological classification. Based on immunohistochemistry of MMR, p53 and POLE mutational analysis, this pragmatic molecular classification scheme can be served as a reliable surrogate for TCGA molecular classification, which has potential to be used routinely in Chinese pathological practice.

[Application and clinical significance of Silva pattern system in invasive endocervical adenocarcinoma].

Objective: To investigate the significance of Silva pattern system about clinical application in invasive endocervical adenocarcinoma. Methods: Data obtained from the Maternity Affiliated Hospital of Dalian Medical University was analyzed, 78 endocervical adenocarcinoma cases were included from December, 2006 to August, 2017. The average age of patients was (45.1±9.1) years old (ranged 27-71 years old). Clinical stage: stageⅠa 26 cases and Ⅰb 49 cases and stage Ⅱa 3 cases. All pathological slides were reviewed, stratified cases into pattern A, B and C according to Silva system criteria. Clinicopathological parameters of three Silva subgroups were analyzed, χ(2) test was used to investigate the correlation of Silva system and clinicopathological parameters. Follow-up data were collected until Jan. 3rd, 2018. The median follow-up time was 41 months (ranged 5-90 months). Kruskal-Wallis H test and Fisher test were used to analyze prognoses among different Silva subgroups. Results: (1) Silva A cases accounted for 38% (30/78) of all patients, 24 cases were stageⅠa, 6 cases were stageⅠb. The median tumor thickness was 2.1 mm (ranged 1.0-10.0 mm). No lymph vascular space invasion (LVSI) and perineural invasion (PNI) was detected, and all lymph node (LN) were negative for metastatic carcinoma. All patients were alive and had no evidence of recurrence. About 21% (16/78) cases were classified as Silva B, including 2 stage Ⅰa and 14 stage Ⅰb. The median tumor thickness was 5.2 mm (ranged 2.0-11.0 mm). Several patients had LVSI (4/16), LN metastasis (1/10) or PNI (1/16), but there was no recurrence or death. Thirty two (41%, 32/78) cases were Silva C, including 29 stage Ⅰb and 3 stage Ⅱa. The median tumor thickness was 11.5 mm (ranged 4.0-21.0 mm). The incidence of LVSI (53%, 17/32), LN metastasis (31%, 8/26) or PNI (16%, 5/32) was significantly increased. There were two recurrent cases and one death cases. (2) Statistical data demonstrated that Silva pattern system was closely correlated with clinicopathological parameters, such as clinical stage (r=0.754, P=0.000), tumor depth (P=0.000) and LVSI (r=0.534, P=0.000). But there was no correlation between Silva system and LN metastasis or PNI (all P>0.05). (3) Silva subgroups demonstrated no significant difference in recurrence and death (P>0.05). Conclusions: The application of Silva pattern system could effectively predict the prognosis of patients. It may be helpful to select reasonable operation before surgery and to realize individualized treatment of cervical adenocarcinoma.

[BABA of da Vinci robot thyroid surgery in the standard treatment of thyroid cancer surgery].

Thyroid cancer is the most common malignant tumor in endocrine surgery. Surgery is the first choice for most patients with thyroid cancer. Da Vinci robot system as the auxiliary system is the most advanced endoscopic surgery, largely to fill the cavity mirror device cannot bend, complex operation and so on insufficiency, has now become an important way of surgical treatment of thyroid cancer, and its curative effect, high safety, but because of the economic cost is higher, is currently not widespread popularity.

[Study of the association between polymorphism of persistent obesity, human leptin gene/leptin receptor gene and molecular subtypes of breast cancer].

Objectives: To explore the association between the polymorphism of persistent obesity and genetic variations in the LEP (human leptin gene, LEP) and LEPR (leptin receptor gene, LEPR) genes and different molecular subtypes of breast cancer. Methods: All 703 female patients of breast cancer diagnosed by histopathology in the Sichuan Cancer Hospital or the West China Hospital, excluding patients with metastatic breast cancer or mental disease, were selected as cases from April 2014 to May 2015. At the same time, 805 healthy women received physical examination in medical examination center of Sichuan People Hospital or Shuangliu maternal and child health care hospital, excluding those with therioma, breast disease, and mental disease, were enrolled in control group. A uniform questionnaire was used to collect general information including demographic characteristic, reproductive history height, weight, and so on. And the obesity status in recent 10 years was judged. Time of Flight Mass Spectrometer was used to determine the genotypes of LEP rs7799039, LEPR rs1137100 and LEPR rs1137101, while the multinomial logistic regression analysis was conducted to estimate the effect of risk factors related to breast cancer in different molecular subtypes; and then, the association between polymorphism of persistent obesity, the LEP, LEPR genes and breast cancer of different molecular subtypes was analyzed by binary logistic regression models. Results: The average age of controls was (48.98±8.83) years old, while the age of cases of TNBC, Luminal A, Luminal B, and HER-2+ were (51.43±11.33), (49.94±10.10), (49.73±9.38), (50.50±9.04) years old, respectively. The frequency of genotype LEP rs7799039, LEPR rs1137100 and LEPR rs1137101 in control group was separately 74.8%(1 157/1 546), 83.6%(1 339/1 602) and 88.4%(1 416/1 602); while 77.6% (1 074/1 384), 82.4% (1 155/1 402) and 87.9% (1 232/1 402) respectively in case group. Compared with non-persistent obesity subjects, the persistent obesity ones showed an increased risk in TNBC (OR=3.58, 95%CI: 1.90-6.72), Luminal A (OR=2.65, 95%CI: 1.35-5.21) and Luminal B (OR=1.90, 95%CI: 1.26-2.89) breast cancer. LEP rs7799039-AA was relevant with the upward risk of Luminal B independently (OR=1.30, 95%CI: 1.00-1.69). Besides, persistent obesity was found to have a combined effect on Luminal B (ß=3.34, 95% CI: 1.00-11.12) with LEPR rs1137101-GG. Conclusion: Persistent obesity could increase the potential risk of TNBC, Luminal A and Luminal B breast cancer. Women who were suffered from persistent obesity with a genotype of LEPR rs1137101-GG were more susceptible to Luminal B breast cancer.

[Association of XRCC1 gene polymorphism and low dose ionizing radiation with peripheral blood lymphocyte micronucleus].

Objective: To explore the effects of X-ray repair cross complementing gene 1 (XRCC1) polymorphism and low dose ionizing radiation exposure on radiology professionals' peripheral blood lymphocyte micronucleus. Methods: A matched case-control study was designed. From 2013 to 2015, 1 102 radiology professionals with micronucleus test rusults, and 45 cases with present micronucleus were enroled into case group. 180 diagnostic radiology technicians detecting no micronucleus were chosen as control group, cases and controls were 1∶4 mached on gender, age ≤40 or >40 years old. According to the detection of micronucleus levels (0‰, 1‰, 2‰) , the objects of our study were divided into the reference group, the low detection group and the medium detection group. The form of radiation workers' occupational health examination was used to collect the general baseline of the research objects, history of smoking, drinking, poisonous and harmful material exposure, past medical history, accumulated illuminated dose and lymphocyte micronucleus rates (‰) , etc. Using restriction fragment length polymorphism polymerase chain reaction (RFLP-PCR) technology for genotyping; Compared the baseline data and radiation exposure level between the differentmicrokernel detection groups; Adopted multivariate logistic regression to analysis the combination effect of XRCC1 Arg399Gln gene polymorphism and accumulated illuminated dosefor micronucleus rate. Results: The accumulated illuminated dose in the reference group, the low detection group and the medium detection group were (23.44±15.23) , (21.76±2.56) , (24.22±18.61) mSv, respectively. There was no statistically significant difference among the groups (P>0.05) . Under the dominant inheritance mode, after adjusted age, smoking and drinking factors, the results suggested that XRCC1 Arg399Gln micronucleus medium detection group compared with the reference group, Arg399Gln-GG as reference, Arg399Gln-GA+AA decreased the occurrence of micronucleus (OR=0.175, 95%CI: 0.036-0.848) . Arg194Trp and Arg280His did not affect the incidence of micronucleus (P>0.05) . Did not find the combination effect of XRCC1 Arg399Gln gene polymorphism and accumulated illuminated dose for micronucleus rate (P>0.05) . Conclusion:XRCC1 Arg399Gln gene polymorphism can affect the incidence of micronucleus, and carrying the XRCC1 Arg399Gln-GA+AA genotype is a protective factor of micronucleus's occurrence, but low dose ionizing radiation may not affect the occurrence of micronucleus independently.

Inflammatory pain memory facilitates occlusal interference-induced masticatory muscle hyperalgesia in rats.

BACKGROUND: Patients with an orofacial pain history appear to be more susceptible to occlusal interference pain in dental practice for unknown reasons. Pain memory has a critical function in subsequent pain perception. This study aims to explore whether orofacial pain memory could affect the masticatory muscle pain perception for occlusal interference. METHODS: Cross-injection of 2% carrageenan into bilateral masseters in male rats was carried out to establish the inflammatory pain memory model. The effects of pain memory on masseter muscle nociception were tested by applying crowns with heights beyond the occlusal plane by 0.2 or 0.4 mm onto a maxillary molar 2 weeks after inflammation in the right masseter. The 0.4-mm crowns were removed on day 2 or day 4 after application to further confirm the effects of pain memory. Moreover, memory impairment was established using ibotenic acid (IBO) infusion into the bilateral hippocampus, followed by behaviour tests, including the Morris water maze test and the locomotor activity test. The relationship between pain memory and occlusal interference-induced masseter muscle pain perception was subsequently re-examined. The head withdrawal thresholds of masseters on both sides were measured to reflect the perception. RESULTS: Inflammatory pain memory aggravated the 0.2-mm crown-induced mechanical hyperalgesia of the masseters, but not in the 0.4-mm crown group. However, the recovery of the 0.4-mm crown-induced mechanical hyperalgesia was postponed. The effects of pain memory were reversed in rats with impaired mnemonic function of the hippocampus. CONCLUSIONS: Inflammatory pain memory facilitated occlusal interference-induced masseter muscle pain.

Expression of connexin 35/36 in retinal horizontal and bipolar cells of carp.

Connexin 35/36 (Cx35/36) gap junction protein is expressed in various regions of the brain, including the retina. In this work, the expression of Cx35/36 in the outer retina of carp was studied by immunocytochemistry. By light microscopy, strong punctate Cx35/36-immunoreactivity was observed in the outer plexiform layer. Double labeling experiments on vertical retinal sections showed that Cx35/36 puncta were localized beneath cone pedicles, stained by recoverin, but not on them. In addition, few of the dendrites of rod-dominant ON type bipolar cells (rod-ON-BCs), stained by PKCalpha, were labelled with Cx35/36 in the retinal sections. In isolated cell preparations, Cx35/36 was clearly expressed on the dendrites of cone-dominant ON type bipolar cells (cone-ON-BCs), but the expression was much less on rod-ON-BCs. Moreover, Cx35/36 puncta were found in the dendrites of isolated horizontal cells (labelled by GAD 65/67) driven by cones, including H1 and H2 cells, but not in those of cells driven by rods (H4 cells). At the ultrastructural level, reaction product was found in H1 and H2 cell dendrites invaginating cone terminals, but not in H4 cell dendrites invaginating rod terminals. Moreover, dendrites of cone-ON-BCs, were also labebed. These results suggest that Cx35/36 could be specifically involved in modulation of the cone signal pathway in the outer retina of carp.

Therapeutic effect of hyperoxygenated solution on acute lung injury induced by oleic acid.

BACKGROUND/AIMS: Hyperoxygenated solution (HOS) has been shown to protect the myocardium, spinal cord and brain from ischemic injury. In this study, we evaluated the effect of HOS on acute lung injury (ALI) induced by oleic acid in rabbits. METHODS: 24 rabbits were randomized into four groups: control (C), oleic acid (OA), inhaled oxygen (OX), and HOS treatment (HOS). The ALI model was produced by administrating oleic acid intravenously. Half an hour after oleic acid infusion, animals received inhaled oxygen at 30% FiO2 or 20 ml/kg HOS intravenously. Various parameters were measured during the 2 h after oleic acid treatment. RESULTS: After treatment with oleic acid, mean arterial pressure and PaO2 decreased significantly compared to group C (p < 0.01), while lung/body ratio, lung water content, and the levels of myeloperoxidase (MPO) and TNF-alpha in the serum and BALF increased significantly (p < 0.01). Histologically, interstitial edema, alveoli exudation and massive inflammatory cell infiltration were observed in the lung. However, when treated with 20 ml/kg HOS, PaO2 significantly increased compared to group OA (p < 0.05). The MPO and TNF-alpha levels in the serum and BALF were decreased (p < 0.01), pulmonary edema was reduced (p < 0.01). Improved pathological manifestations were observed. CONCLUSION: HOS at 20 ml/kg has therapeutic effects to ameliorate the biological and morphological changes to the lung induced by oleic acid. HOS is a safe, simple and effective measure to protect animals from ALI.