[Clinicopathological analysis of gonadal differentiation of sex development disorder]

Objective: To investigate pathological features and differential diagnosis in the gonads with disorder of sex development. Methods: Thirty-six cases of clinically diagnosed hermaphroditism with gonadal biopsy in the Department of Pathology, the Seventh Medical Center of People's Liberation Army General Hospital from April 2007 to July 2021, were collected. All biopsy pathological sections were reviewed, and the gonadal cases with abnormal pathological morphology were screened out. The clinical and imaging data and karyotype of these cases were reviewed. Additional immunohistochemical staining was performed and relevant literature was reviewed. Results: Seven cases of ovotesticular disorder of sex development (OTDSD) were identified, which were characterized by the presence of testicular and ovarian differentiation in the same individual. All patients were under 15 years old and presented with abnormal appearance of external genitalia, and the ratio of male to female was 2∶5. Ultrasonography showed testicular structure in all female patients and cryptorchidism in all male patients. The most common karyotype was 46, XX. One case with undifferentiated gonadal tissue (UGT) and one case with streak gonads were screened out. UGT germ cells were neither in seminiferous tubules nor in follicles, but randomly distributed in an ovarial-type interstitial background, sometimes accompanied by immature sex cords. Streak gonads resembled UGT without germ cells. FOXL2 was positive in granulosa cells, but negative in Sertoli cells. SOX9 expression was opposite. OCT4 was weakly positively/negatively expressed in oocytes and positively expressed in the germ nuclei of UGT. Conclusions: Four differentiation patterns need to be identified in the gonadal biopsy: ovarian differentiation, testicular differentiation, undifferentiated gonadal tissue and streak gonad. The positive expression of SOX9 indicates testicular differentiation, while the positive expression of FOXL2 confirms ovarian differentiation, and the expression of both markers in the same tissue indicates ovotestis differentiation. It is very important to identify UGT, because that has a high probability of developing into gonadoblastoma in the future.

[Prognostic significance of immunoparesis in newly diagnosed multiple myeloma patients who achieved deep response]

Objective: To evaluate the effect of immune status on disease progression in patients with newly diagnosed multiple myeloma (NDMM) achieving deep response. Methods: Clinical data of 125 NDMM patients at Beijing Chaoyang Hospital from August 2015 to February 2020 were retrospectively analyzed who achieved very good partial response (VGPR) or better after front-line treatment. The immune status and its influence on progression-free survival (PFS) were analyzed. Results: (1) All patients received novel drug regimens, and 50.4% (63/125) patients followed by autologous stem cell transplantation (ASCT). The rate of complete response (CR) as best efficacy was 89.6%, in which 66.4% achieved CR and MRD negativity tested by second generation flow cytometry. (2) Cox multivariate analysis suggested that persistent severe immunoparesis 3 months and 6 months since the best response was an independent poor prognostic factor for PFS. (3) The 3-year PFS rate in the severe immunoparesis group was significantly lower than that in the control group (41.3% vs. 64.4%, P=0.021). (4) The 3-year PFS rates in patients with persistent severe immunoparesis at 3 months or 6 months were significantly lower (30.0% vs. 63.5%, P<0.001; 16.4% vs. 63.8%, P<0.001 respectively). (5) Even in those achieving CR and negative MRD, the 3-year PFS rate when severe immunoparesis lasted 6 months was significantly lower (22.2% vs. 83.2%, P=0.005). Conclusion: The immune status in NDMM patients achieving deep response is closely related to survival. Persistent severe immunoparesis indicates early progression of the disease.

[The prognostic value of dynamic minimal residual disease after autologous hematopoietic stem cell transplantation in patients with multiple myeloma in novel-agent era]

Objective: To investigate the clinical prognostic value of dynamic minimal residual disease (MRD) after autologous hematopoietic stem cell transplantation (AHSCT) in patients with multiple myeloma (MM). Methods: Patients with MM who underwent AHSCT in Beijing Chao-Yang Hospital from February 2016 to December 2019 were enrolled in this study. All the patients in the study had complete baseline data at the diagnosis. AHSCT was performed after induction chemotherapy. Response evaluation was performed after induction therapy. All the patients were assessed at approximately 100 days after AHSCT. Bone marrow MRD by NGF was performed every three months and dynamically monitored for at least 12 months. All the patients were divided into different groups according to cytogenetics and MRD status. Survivals in different groups were analyzed by IBM SPSS 22.0 statistical software. Results: A total of 150 patients with MM were enrolled in this study at last, including 66 patients in the cytogenetic standard risk group and 84 patients in the cytogenetic high-risk group. The median age was 54 years (range 30-68 years) and 87 male patients (58.0%) was in the study. The median follow-up was 36 months (range 16-72 months). Patients in the standard-risk group had better clinical prognosis than those in the high-risk group [median PFS in the standard-risk group was not achieved, and median PFS in the high-risk group was 45 months (P<0.001); median OS of both groups was not reached, and the estimated 3-year OS rate of the standard-risk group and the high-risk group was 95.2% and 78.9%, respectively (P=0.001)]. According to MRD status of patients, patients in each group were divided into three subgroups: persistent positive (Ppos), transient negative (Tneg) and persistent negative (Pneg). The median OS and median PFS of all subgroups in the standard-risk group was not reached (P=0.324 and P=0.086). In high-risk group, the median OS of MRD Pneg subgroup was not reached, and the estimated 3-year OS rate was 100%; The median OS of MRD Ppos subgroup was 52 months, and MRD Tneg subgroup only 31 months (P=0.002); the median PFS of MRD Pneg group was not reached, and the estimated 3-year PFS rate was 85.4%; median PFS of MRD Ppos subgroup was 40 months, and MRD Tneg subgroup only 17 months (P=0.001). Conclusions: MRD Pneg might overcome the adverse prognosis of MM patients with high-risk cytogenetics. However, MRD Tneg might be a poor prognostic factor for the patients with cytogenetic high-risk MM.

[Expression of PD-L1 and tumor infiltrating lymphocyte markers in uterine cervical carcinoma]

Objective: To investigate the expression of PD-L1, CD4, CD8 and CXCL-13 in cervical carcinoma, and their clinicopathological significance was analyzed. Methods: A total of 77 patients with cervical carcinoma in the Seventh Medical Center, PLA General Hospital from January 2019 to December 2021 were included. All patients received radical surgical resection in the Seventh Medical Center of Chinese PLA General Hospital. The expression of PD-L1, CD4, CD8 and CXCL-13 was detected by immunohistochemical (IHC) method. The correlation between IHC markers and patients' clinicopathological parameters was analyzed. Results: There were 59 cases of squamous cell carcinoma and 18 cases of adenocarcinoma (ranging from 29 to 69 years) with an average of (49.4±9.8) years. PD-L1 was expressed in different degrees in cervical squamous cell carcinoma and adenocarcinoma (χ²=4.975, P=0.026); CD4⁺, CD8⁺and CXCL-13⁺tumor infiltrating lymphocytes (TIL) were observed in the carcinoma cell nests and peritumoral stroma. PD-L1 expression in cervical carcinoma was moderately correlated with the number of CD4⁺TIL in the carcinoma nests, and the number of CD8⁺, CXCL-13⁺TIL infiltration in the carcinoma nests and stroma, but not to the patient's age, histologic differentiation, presence or absence of vascular invasion, presence or absence of lymph node metastasis and FIGO stage (P>0.05). Conclusions: The high expression of PD-L1 in cervical carcinoma tissues is closely related to the number of TIL in the carcinoma nests and peritumor stroma, suggesting that they may have important reference value for predicting the response to immunotherapy in patients with cervical carcinoma.

[Clinicopathological features of malignant mixed mesodermal tumor: analysis of 50 cases]

Objective: To investigate the clinicpathological, immunohistochemical and molecular genetic features of malignant mixed mesodermal tumor (MMMT) in the female reproductive system. Methods: To analyze its histopathological characteristics, we performed a retrospective review of the MMMT cases diagnosed at PLA General Hospital, Beijing, China during 2005-2019 using its surgical and pathological databases. EnVision immunohistochemical staining was used to detect the expression of ER, PR, p16, p53 and MMR proteins. Results: Fifty cases were conformed to the diagnosis, including 29 cases originated in the uterus, 16 cases in ovary, 4 cases of synchronous occurrence in uterus and ovary, 1 case in cervix. The tumor was histologically composed of two components, namely carcinoma and sarcoma ones, with clear borderline or blend mutually. The proportion of cancer component in the whole tumor ranged from 5%-90%. The proportion of carcinoma was more than 50% in 76% of the cases, and less than 50% in 24% of cases, including 2 cases with<10% of carcinoma. In the cases of primary uterine MMMT, the main carcinoma type was high grade endometrioid carcinoma (55%, 16/29). In ovarian MMMT, the main carcinoma type was serous carcinoma (12/16), while that of cervical MMMT was squamous cell carcinoma. The others were clear cell carcinoma or the undifferentiated carcinoma. There was one carcinoma type in most cases, only 7 cases had two carcinoma types. Homologous sarcomas, including stromal sarcoma, leiomyosarcoma and high-grade spindle cell sarcomas, were more commonly found in uterine MMMT (72.4%, 21/29). While heterogenic sarcomas, including chondrosarcoma, osteosarcoma and rhabdomyosarcoma, were more commonly noted in ovarian MMMT (12/16) than MMMT of other sites. There were 10 cases that consisted of two types of sarcomas. The synchronous MMMT of uterus and ovary had similar morphology and the types of carcinoma and sarcoma. The tumor cells that spread or metastasized to lymph node, omentum, intestinal wall or skin were all carcinoma cells, and were morphologically consistent with the original tumors. Immunohistochemically, ER and PR were both negative (23/25 in uterine, 8/10 in ovarian tumors). p16 was strongly positive (11/11 in uterine tumors, and 6/6 in ovarian tumors), with similar expression patterns in the carcinoma and sarcoma components. p53 showed mutant-type staining (64%, 21/33) and expressed synchronously in carcinoma and sarcoma components. p53 mutation was found in 35% cases of endometrial carcinoma and 46.7% cases of non-endometrial carcinoma. p53 mutation was also found in only 31.8% cases of heterogenic sarcomas, but in 50% of non-heterogenic sarcomas. Twenty-eight cases (28/33, 85%) presented intact mismatch repair proteins, while 5 cases (5/33, 15%) presented deficient mismatch repair proteins. Conclusions: MMMT in female reproductive system is a rare high-grade biphasic tumor with complex and diverse morphology. The immunohistochemical features are characterized by negative ER/PR and strongly positive p16, mostly mutant p53 and proficient mismatch repair proteins. The patients with a high FIGO stage have worse prognosis.

[Artificial intelligence aided measurement of cervical squamous epithelial thickness and its correlation with cervical precancerous lesions]

Objective: To study the thickness of cervical squamous epithelia and its correlation with cervical precancerous lesions. Methods: We selected 495 HE slides of 209 cervical biopsies from January 2020 to June 2020 in the Department of Pathology, the First and Seventh Medical Center of the PLA General Hospital, including 173 slides with low grade squamous intraepithelial lesion (LSIL) and 214 slides with high grade squamous intraepithelial lesion (HSIL). Artificial intelligence labeling software was used to assist in measuring the epithelial thickness of normal cervical squamous epithelium, LSIL and HSIL of each slide. The thickest, thinnest, and middle widths of epithelial thickness were measured, respectively. Average epithelial thickness was defined as the sum of the above three widths divided by 3. The correlation statistical analysis was performed by combining the data of age and pathological diagnosis. Results: The average thickness of normal cervical squamous mucosa was (245.83±91.40) μm, which was (222.42±81.22) μm and was (195.95±66.59) μm in LSIL and HISL epithelial respectively (F=27.09, P<0.01). The average cell layers of normal cervical squamous epithelium was (15.5±4.2) layers, which of LSIL was (14.8±4.8) layers, and that of HSIL was (15.8±4.8) layers. The differences among normal, LSIL and HSIL were not statistically significant (P>0.05). Further statistical analysis was stratified by age (≤30 years, 31-40 years, 41-50 years, 51-60 years, and >60 years), the results of Pearson correlation analysis showed that the thickness of normal cervical squamous epithelial gradually thinned with age (correlation coefficient r=-0.141 9, P<0.05), while LSIL and HSIL epithelial thickness had significant correlation with age (P>0.05). In the subgroup of ≤50 years old, the epithelial thickness of normal squamous epithelium was the thickest, followed by LSIL, and HSIL epithelial thickness was the thinnest. The differences were statistically significant (P<0.05). While in the subgroup of >50 years, the differences were not statistically significant (P>0.05). Conclusions: The cervical squamous epithelium gradually becomes thinner with the degree of precancerous lesions increasing among patients of ≤50 years old. However, after age of 50 years, with the onset of menopause, the normal mucosal epithelium is becoming atrophy, so that mucosal thickness is no longer correlated with the extent of the lesion. In addition, it is suggested that the cervical vinegar white test performance during colposcopy is related to the protein changes in the mucosal epithelial cells, but not directly related to the thickness of the epithelial layer.

[Comparison of the clinicopathological features between adenoid basal cell carcinoma and adenoid cystic carcinoma of the cervix]

Objective: To compare the clinical and histopathological characteristics of cervical adenoid basal cell carcinoma and adenoid cystic carcinoma for improving the diagnosis accuracy and differential diagnosis of these tumors. Methods: A retrospective study was conducted on 9 cases of cervical adenoid basal cell carcinoma and 3 cases of adenoid cystic carcinoma which were diagnosed and consulted at the First Medical Center of PLA General Hospital from March 2009 to April 2019. Detailed clinical data were reviewed. All pathological sections and immunohistochemical results were reviewed and the clinicopathological characteristics were analyzed. Follow-up information by telephone was collected and relevant literature was consulted. Results: Both tumors were more commonly found in postmenopausal women (the age of onset ranged 43-74 years). Adenoid basal cell carcinoma was often clinical asymptomatic. Most of them presented as abnormal smears of the cervix during physical examination, and there was no definite mass in colposcopy.Adenoid cystic carcinoma was mostly presented with abnormal vaginal bleeding. A mass was seen in colposcopy.Histologically, the two tumors were characterized by nest-like growth of the tumors, consisting of basal-like tumor cells, and often surrounded by palisade structures. The two lesions might coexist, or be mixed with squamous cell carcinoma or high-grade squamous intraepithelial lesions. The difference was that adenoid basal cell carcinoma was mostly located at the junction of cervical squamous epithelium and columnar epithelium and beneath the overlying epithelium, the tumor cells were arranged in nests, with squamous differentiation in the center of the nests, or in double-layer adenoid arrangement. The cell morphology was bland with occasional mitoses, and the stromal reaction was not obvious. And adenoid cystic carcinoma cells in the nest arranged like a sieve, the homogenous red-stained and blue-stained secretions were observed in the sieve holes, with obvious cell atypia, frequent mitoses, and obvious stromal reaction.In one case of adenoid cystic carcinoma, sarcomatoid area presented around the nests.Both of them were positive in clinical HPV test. Among the 9 cases of adenoid basal cell carcinoma, 3 were tested for HPV and 5 were tested for p16, and all showed positive expression. Among the 3 cases of adenoid cystic carcinoma, 2 were tested for HPV and 3 were tested for p16, both of which showed positive expression. Telephone follow-up was conducted by June 2019(follow-up time ranged 2-37 months). No recurrence or metastasis occurred in 7 of the 9 cases of adenoid basal cell carcinoma, while 1 case had a ground-glass nodule in lung and another had recurrence of vaginal stump 32 months after the surgery.One case of adenoid cystic carcinoma developed lung metastasis 8 months after surgery and died 2 years after surgery; another case was followed up for 6 months, which showed no recurrence or metastasis; the third case was lost to follow-up. Conclusions: Both adenoid cystic carcinoma and adenoid basal cell carcinoma of the cervix are the tumors originating from cervical reserve cells and are associated with high-risk HPV infection. Due to the differences in clinical treatment and prognosis, careful histological evaluation and immunohistochemical analysis should be carried out to make accurate pathological diagnosis.

[Expression of ARID1A in ovarian seromucinous neoplasms and its clinicopathological significance]

Objective: To investigate the clinical, pathological and immunohistochemical features of seromucinous neoplasms, including seromucinous cystadenoma, borderline tumour and seromucinous carcinomas of the ovary. Methods: A retrospective review of the seromucinous neoplasms collected between June 2006 and December 2018 was conducted at the First Medical Center of PLA General Hospital. EnVision immunohistochemical staining was used to detect the expression of CK7, PAX8, ER, PR, WT1, p16, p53 and Baf250a which was encoded by the ARID1A gene. Results: A total of 75 ovarian seromucinous neoplasms were included. There were 30 cases of benign seromucinous cystadenoma, whose patients aged 12 to 83 years (mean, 36 years). The tumor histologically composed of endocervical-type mucinous epithelium and serous-type cells, each of which accounted for more than 10%. Among the 34 cases of seromucinous borderline tumour including 7 cases with concurrent endometriosis, the patients aged 21 to 72 years (mean, 39 years). Characteristic histologic features were broad papilla structure and an admixture of cell types, predominant endocervical-like mucinous cells (non-intestinal, no goblet cells), eosinophilic cells and others such as clear cells, hobnail cells, ciliated cells, and endometrioid cells. The larger papillae tended to have oedematous stroma containing neutrophils. In the 11 cases of seromucinous carcinomas including 2 cases with concurrent endometriosis, patients aged 26 to 61 years (mean, 40 years). Seromucinous carcinomas exhibited a predominant papillary architecture with smaller components of confluent glandular, microglandular and solid structure, expansive stromal invasion pattern, and sometimes locally destructive infiltration. An admixture of epithelial cell types was in seromucinous carcinomas, as well as borderline tumour. Immunohistochemically, the tumours were positive for CK7, PAX8, p16, estrogen receptor and progesterone receptor (positive in 10% to 80% of the cases). They were negative for WT1, while p53 staining showed a "wild-type" pattern. The Ki-67 positive rate was 20% to 60%. Loss of ARID1A-encoded protein Baf250a staining was observed in 6 (30%) of the 20 seromucinous borderline tumors, and 2 of the 11 seromucinous carcinomas. According to FIGO 2014 staging system, there were 4 cases of ⅠA, 3 cases of ⅡA and 4 cases of ⅢC. Follow-up information was available in 9 patients of seromucinous carcinomas, and 2 lost to follow-up. Eight were alive (follow-up for 6 to 108 months), including 2 patients with relapse, but 1 patient who initially presented with a stage ⅢC tumor died of disease 60 months after the cancer diagnosis. Thirty-four patients of borderline tumour were all alive at the end of follow-up, including 1 with relapse. Conclusions: Seromucinous neoplasms have characteristic histopathological and immunopathological features. Both borderline tumors and carcinomas have complex structures and cellular components. ARID1A as a tumor-suppressor gene plays a role in the oncogenesis of ovarian seromucinous neoplasms. The loss of staining with ARID1A-encoded Baf250a and wild-type p53 in seromucinous neoplasms together support that seromucinous neoplasms could be type Ⅰ tumor of dualistic model of epithelial ovarian cancer, with favourable prognosis.

[Phenotype study of SCN2A gene related epilepsy]

Objective: To summarize the phenotype of epileptic children with SCN2A mutations. Methods: Epileptic patients who were treated in the Pediatric Department of Peking University First Hospital from September 2006 to October 2017 and detected with SCN2A mutations by targeted next-generation sequencing were enrolled. Clinical manifestations of all patients were analyzed retrospectively. Results: A total of 21 patients (16 boys and 5 girls) with SCN2A mutations were collected. Twenty-one SCN2A mutations were identified. Ten patients had mutations inherited from one of their parents and 11 patients had de novo mutations. The age of epilepsy onset was from 2 days to 2 years and 6 months: six patients with seizure onset in neonates (29%) , six patients with seizure onset between 1 month and 3 months of age (29%), three patients with seizure onset between 4 months and 6 months of age, two patients with seizure onset between 7 months and one year of age, and four patients with seizure onset beyond one year of age. Multiple seizure types were observed. The focal seizure was the most common seizure type which was observed in 18 patients (86%) . Spasm seizure was observed in 6 patients (29%) . Other seizure types were rare. In 19 patients, seizures manifested in clusters (90%) . In 3 patients, seizures manifested fever-sensitive. Nine of ten patients with inherited SCN2A mutations had normal development. However, all patients with de novo SCN2A mutations had mild or severer development delay. In 21 patients with SCN2A mutations, five were diagnosed with benign familial infantile epilepsy, 3 with benign familial neonatal-infantile epilepsy, 3 with Ohtahara syndrome, 3 with West syndrome, 2 with encephalopathy with early infantile onset epilepsy, one with febrile seizures plus, one with Dravet syndrome, one with encephalopathy with childhood-onset epilepsy, one with autism with epilepsy and one with intellectual disability with epilepsy. Conclusions: The clinical features of patients with SCN2A mutations include that main seizure onset is the neonate and early infancy, and the main seizure type is the focal seizure, manifested in clusters. The large spectrum of SCN2A-related epilepsy, which not only includes epilepsy with a comparatively favorable prognosis, but also epileptic encephalopathy. De novo mutations often lead to severe phenotype with development delay.

Abstract P1-14-02: A phase 2 study of low dose metronomic eribulin in metastatic breast cancer

Background: Eribulin mesylate is a non-taxane microtubule dynamics inhibitor approved by FDA in treatment of metastatic breast cancer (MBC) based on improvements in overall survival in the pivotal EMBRACE trial. Eribulin is approved at 1.4mg/m2 administered D1,8 of q21d cycle. However, this dose and schedule may have significant myelosuppression and peripheral neuropathy requiring dose reductions and treatment delays for some patients. We hypothesized that a low dose metronomic schedule will allow responding patients to remain on treatment, resulting in longer TTP (time to progression) and decreased incidence of toxicities and treatment-related discontinuations.

Methods: A multi-site prospective open-label phase II trial of metronomic dosing of eribulin in patients with MBC has completed accrual of 60 patients, outcomes will be updated at presentation. Patients whose disease had progressed following 1-6 prior regimens with prior exposure to a taxane, ECOG performance status of 0 – 2, measurable disease per RECIST 1.1, with normal marrow and organ function were eligible. Eribulin was administered at 0.9mg/m2 weekly for 3 out of 4 weeks. For patients with HER2 positive disease, concurrent trastuzumab administration was allowed. Concurrent denosumab or bisphosphonates were allowed for patients with bone disease.

Results: 60 patients were enrolled, average age 58 (range 34-83). Majority were postmenopausal Caucasian females, but the study included African American, Hispanic, native American, male patients. The majority of tumors were ER+, infiltrating ductal, but the study included 13 HER2+, and 12 TN tumors, with 5 ILC, and 5 mixed ILC/IDC. Nearly half of the enrolled patients had clinical benefit from the regimen, remaining on therapy for 6 months or longer, with stable disease or response; 50% had progression PD at 3 months 32% had stable disease and 18% had a partial or complete response (1, long term). Overall Survival, OS, for the entire group of heavily pre-treated patients was 1.2 years, with TN and HER2 positive patients faring better than ER+ in this small study. One HER2+ patient remains in long-term remission, off chemotherapy.

The regimen was extremely well tolerated. The majority of the patients experienced grade 0 or 1 toxicity for alopecia (48/60) and peripheral neuropathy (7 with grade 2 neuropathy, 5 pre-existing, 2 with grade 3 neuropathy). There were few dose reductions (n=15), thrombocytopenia (11 grade 1 only), or use of G-CSF (14).

Conclusions: Metronomic weekly low dose eribulin appears to be an active and tolerable regimen with less myelosuppression, alopecia and peripheral neuropathy than is seen with approved dose, allowing longer duration of use and disease control, with similar outcomes compared to the standard dose regimen. Outcomes will be updated at presentation.

Citation Format: Chalasani P, Liu AJ, Khanjian JA, Peha M, Buening BJ, Gadi VK, Specht JM, Salazar L, Linden HM. A phase 2 study of low dose metronomic eribulin in metastatic breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-14-02.

[Clinicopathological analysis of cervical basaloid squamous cell carcinoma]

Objective: To investigate the clinical and histopathological features of cervical basal squamous cell carcinoma (BSCC). Methods: A retrospective analysis of 10 cases of cervical BSCC was carried out. The clinical data and all the pathological sections were reviewed, the related immunohistochemical results were statistically analyzed, the clinicopathological features were analyzed, and then followed the prognosis. Results: (1) Clinical features: the median onset age of BSCC in cervix was 51 years old (ranged 35-69 years old), 5 of them were postmenopausal women. Vaginal bleeding was often seen in clinic (7 cases). Of the 10 cervical BSCC patients, 5 tested HPV types. All of them were HPV positive, including 2 cases of HPV 16 positive and 1 case of high-risk HPV positive. At the time of colposcopy, 3 cases showed exogenous nodular mass, 3 cases showed endogenous infiltrating mass, and 4 cases had unclear type of mass.(2)Treatment: of the 10 patients, 8 underwent hysterectomy+bilateral adnexal excision+pelvic lymphadenectomy, of which 6 underwent radiotherapy or chemotherapy after operation.Radiotherapy and chemotherapy were performed only in 2 cases. (3) Pathological features: histologically, the tumor cells were nests and stripe like growth, which were composed of basal like tumor cells. The cells had obvious heteromorphosis, less cytoplasm, deep dyed nuclei and common nuclear mitosis, and there were often palisade like structures around the cell nests, and some cells in the center of the cell nests were found to have acne like necrosis. It could be mixed with normal squamous cell carcinoma and squamous epithelial lesion. Among the 10 patients, 6 had immunohistochemical results. BSCC mainly expressed p16 and squamous cell markers such as p63, cytokeratin (CK) 5/6 and p40 protein, the positive expression rates were 3/3, 3/3, 2/2 and 3/3, respectively. A few expressed CK7 protein, and the positive expression rate was 1/3. (4) Prognosis: follow-up time ranged from 1 week to 64 months, and 2 cases were lost to follow-up. Among the 8 follow-up patients, 3 had iliac bone, lung or skin metastasis, and 5 had no recurrence or metastasis during the follow-up period. Conclusions: BSCC of cervix is a rare malignant tumor of cervix associated with high-risk HPV infection, p16 is more positive. The treatment is similar to that of normal cervical squamous cell carcinoma. Surgical resection and radiotherapy and chemotherapy are the most effective methods according to the clinical stage. At present, the disease is considered to be highly aggressive and the poor prognosis.

Heterogeneous Activation, Local Structure, and Softness in Supercooled Colloidal Liquids

We experimentally characterize heterogeneous nonexponential relaxation in bidisperse supercooled colloidal liquids utilizing a recent concept called "softness" [Phys. Rev. Lett. 114, 108001 (2015)PRLTAO0031-900710.1103/PhysRevLett.114.108001]. Particle trajectory and structure data enable classification of particles into subgroups with different local environments and propensities to hop. We determine residence times t_{R} between particle hops and show that t_{R} derived from particles in the same softness subgroup are exponentially distributed. Using the mean residence time t[over ¯]_{R} for each softness subgroup, and a Kramers' reaction rate model, we estimate the activation energy barriers E_{b} for particle hops, and show that both t[over ¯]_{R} and E_{b} are monotonic functions of softness. Finally, we derive information about the combinations of large and small particle neighbors that determine particle softness, and we explicitly show that multiple exponential relaxation channels in the supercooled liquid give rise to its nonexponential behavior.

[Prognosis-related clinicopathologic characteristics of FIGO stage Ⅰ Müllerian adenosarcoma of uterus]

Objective: To investigate the clinicopathological features of FIGO stage Ⅰ uterine Müllerian adenosarcoma and clinical prognosis. Methods: Fifteen cases of uterine Müllerian adenosarcoma at FIGO stage Ⅰ were collected at PLA General Hospital from 2005 to 2017. Twelve cases with complete follow-up data were divided into 2 groups: group A (7 patients with survival) and group B(5 patients of death or tumor progression). Clinicopathologic features were compared between the two groups. Results: The median age of the patients was 43 years and 56 years, and the tumor size was 4.3 cm and 7.3 cm for group A and B, respectively. Cases in group A were FIGO ⅠA and ⅠB stage tumors and were mainly low grade in histology (5/7) with rare tumor hemorrhagec, necrosis (1/7) and sarcomatous overgrowth. In contrast, most cases in group B were high grade sarcomas(3/5) with frequent hemorrhage, necrosis(3/5) and sarcomatous overgrowth(4/5). Most cases of group A expressed ER, PR and CD10 (6/7) and low Ki-67 index of ≤20%(5/7). While most group B cases lost expression of ER and PR (3/5), significantly reduced expression of CD10 and higher Ki-67 index of ≥30%(4/5). Conclusions: Most of uterine adenosarcomas are of low malignant potential. The main prognostic indicator is advanced tumor stage. For patients at stage Ⅰ, sarcomatous overgrowth, high-grade histology, deep myometrial invasion, decreased or absent expression of CD10, ER and PR, increased Ki-67 index(≥30%) and hemorrhagic necrosis may indicate poor prognosis. Müllerian adenosarcomas arising from endomeriosis may present unusual growth patterns.

[Spectrum of mutations in benign familial neonatal-infantile epilepsy]

Objective: To investigate the spectrum of mutations in families with benign familial neonatal-infantile epilepsy (BFNIE) . Methods: Clinical data and peripheral blood DNA samples of all BFNIE probands and their family members were collected from Peking University First Hospital between December 2012 and April 2016. Clinical phenotypes of affected members were analyzed. Genomic DNA was extracted from peripheral blood samples with standard protoco1. Mutations in PRRT2 were screened using Sanger sequencing. For families that PRRT2 mutations were not detected by Sanger sequencing, candidate gene mutations were further screened by next-generation sequencing for epilepsy. Results: A total of 7 families were collected. Of the 30 affected members, 15 were male and 15 were female. The age of epilepsy onset was from 2 days to 6 months. Genetic testing led to the identification of gene mutations in all families. One family had the PRRT2 hotspot mutation (c.649dupC). Three families had missense SCN2A mutations (c.2674G>A/p.V892I, c.2872A>G/p.M958V, and c.2627A>G/p.N876S) . Both c.2872A>G/p.M958V and c.2627A>G/p.N876S were novel SCN2A mutations. Three families had KCNQ2 mutations. Two of them had missense mutations (c.958G>A/p.V320I and c.998G>A/p.R333Q) . The KCNQ2 mutation c.958G>A/p.V320I was novel. One family had a gene deletion of KCNQ2, which also extended to the adjacent gene, CHRNA4; and the deletion involved all the exons of KCNQ2 and CHRNA4. Conclusions: Mutations in KCNQ2, SCN2A, and PRRT2 are genetic causes of BFNIE in Chinese families. The detection rate for gene mutations is high in BFNIE families. KCNQ2 and SCN2A mutations are common in BFNIE families. SCN2A mutations (c.2872A>G/p.M958V and c.2627A>G/p.N876S) and KCNQ2 mutation (c.958G>A/p.V320I) are novel mutations.

[Clinical features and gene mutations in epilepsy of infancy with migrating focal seizures]

Objective: To summarize the clinical features and gene mutations of epilepsy of infancy with migrating focal seizures (EIMFS). Method: Clinical features and electroencephalograms(EEG)of 9 patients with EIMFS of Peking University First Hospital from May 2015 to January 2016 were analyzed. Candidate gene mutations were screened by next generation sequencing. Result: Among the 9 patients, 3 were males and 6 were females. Two patients had family history. Seizure onset age was 2 days to 3 months after birth (median age 35 days). Migrating focal seizure was presented. Seizures manifested as eyes and(or)head deviation, involuntary blinking, swallowing, trembling or stiffness of limbs, hand clenching, flushing and cyanosis of lips, etc. Four patients had a history of status epilepticus. All 9 patients had psychomotor delay. EEG of all patients presented relatively slow background; during interictal phase, there were multi-focal epileptic discharges, which dominated one hemisphere or brain region; seizures were recorded in all 9 cases, which manifested eyes or(and)head deviation, stiffening or trembling of limbs, lip smacking, etc. Corresponding EEG showed low-medium-amplitude fast waves that originated from some brain regions and migrated to other regions. Cranial magnetic resonance imaging (MRI) was abnormal in 4 cases, which predominantly showed white matter dysplasia and enlargement of subarachnoid spaces. Two cases carried heterozygous missense mutations of SCN1A gene, while 3 cases carried heterozygous missense mutations of KCNT1 gene, all of which were de novo. One case carried compound heterozygous mutation of TBC1D24 gene(p.Gln207*, p. Ala289Va). Gene mutation was not found in 3 cases. All patients used multiple antiepileptic drugs (AED) and their seizures were not controlled. Follow-up ranged from 2 months to 5 years and 8 months, during which 4 were found dead. Two were lost to follow-up. Conclusion: EIMFS is clinically characterized by early onset, which is usually within 3 months after birth, migrating focal seizures, psychomotor delay, bad response to AED and high death rate. The interictal EEG showed multi-focal discharges, while ictal EEG shows migrating multifocal discharges. Genetic analysis can assist in diagnosis and genetic counseling.

[A prospective study of the efficacy and safety of maintenance therapy with recombinant human thrombopoietin in patients with primary immune thrombocytopenia: a multicenter study]

Objective: To evaluate the efficacy and safety of maintenance therapy with reduced dose of rhTPO in the patients with primary immune thrombocytopenia (ITP) who attained stable platelet (PLT) counts after daily administration of rhTPO. Methods: Treatment was started with a daily administration of rhTPO (300 U/kg) for 2 consecutive weeks. Patients who attained stable PLT≥50×10(9)/L were enrolled to maintenance therapy starting with every other day administration of rhTPO, then adjusted dose interval to maintain platelet count (30-100) ×10(9)/L. Results: A total of 91 eligible patients were enrolled. Fourteen patients discontinued the study due to noncompliance (12/14) and investigator decision (2/14) . Among 77 patients who completed the study, 38 patients with the administration of rhTPO at every other day or less could maintain PLT≥30×10(9)/L for 12 weeks. The percentage of patients with a platelet response (PLT≥30×10(9)/L) at 4(th) week, 8(th) week and 12(th) week of maintain therapy was 92.6% (63/68) , 82.7% (43/52) and 85.0% (34/40) , respectively. Median platelet counts remained in the range of (70-124) ×10(9)/L. The overall incidence of rhTPO-related adverse events was 7.7%. All the adverse events were generally mild. Conclusion: Extending the dose interval of rhTPO is feasible to maintain stable platelet count in the patients with ITP, but the optimal dose interval is uncertain and might vary with individuals.

[Clinical and neuroimaging features of acute encephalopathy after status epilepticus in Dravet syndrome]

Objective: To investigate the clinical and neuroimaging characteristics of acute encephalopathy (AE) after status epilepticus (SE) of patients with Dravet syndrome (DS). Method: The clinical data of DS patients who had AE (coma ≥24 h) after SE were retrospectively collected from February 2005 to August 2016 in Peking University First Hospital and SCN1A gene tests were performed.The clinical and neuroimaging features were summarized. Result: Twenty-two patients (9 males and 13 females) with AE were collected among 412 DS patients during follow-up.Of which 18 patients had SCN1A gene mutations while the remaining 4 patients had no SCN1A gene mutations.The onset age of AE was between 6 months and 10 years.The duration of SE varied between 40 minutes and 9 hours.Prior to the onset of SE, twenty-one patients had high fever, and one patient had normal temperature.Coma lasted from 2 days to 20 days.Nine patients died after the AE, and 13 patients survived with massive neurological regression.From AE to the last visit, the median time of follow-up was 2 years and 3 months (from 7 months to 4 years and 4 months). Nine of 13 survivors had varied improvement in motor, language and cognition, while the remaining 4 patients had no significant improvement.After AE, there were 6 patients with seizure-free, 4 patients with reduced seizures, and 3 patients with no change in seizure frequency, moreover, spasm occurred in 2 patients.Six patients had brain magnetic resonance imaging (MRI) in acute phase and showed bilateral (2 patients) or unilateral (4 patients) hemisphere edema, accompanied by subcortical white matter hyperintense signal in T1 and T2 weighted images in two patients.The neuroimaging of 13 survivors demonstrated diverse cortical atrophy during recovery phase, among which 4 patients showed cerebellar atrophy, one patient had right pontine atrophy, 4 patients accompanied by signal abnormalities in subcortical and periventricular white matter, 2 patients showed right hippocampal sclerosis, and one patient showed signal abnormalities in bilateral basal ganglia. Conclusion: SE is more prone to occur in Dravet patients who have high fever.It may result in AE or even death in severe cases.Survivors will leave severe neurological sequelae.The neuroimaging shows brain edema in acute phase.In recovery phase the neuroimaging shows diverse brain atrophy, moreover, a few patients may be associated with cerebellar or pontine atrophy, hippocampal sclerosis or abnormal signals in white matter or basal ganglia.

Retinal Inhibition of CCR3 Induces Retinal Cell Death in a Murine Model of Choroidal Neovascularization

Inhibition of chemokine C-C motif receptor 3 (CCR3) signaling has been considered as treatment for neovascular age-related macular degeneration (AMD). However, CCR3 is expressed in neural retina from aged human donor eyes. Therefore, broad CCR3 inhibition may be harmful to the retina. We assessed the effects of CCR3 inhibition on retina and choroidal endothelial cells (CECs) that develop into choroidal neovascularization (CNV). In adult murine eyes, CCR3 colocalized with glutamine-synthetase labeled Műller cells. In a murine laser-induced CNV model, CCR3 immunolocalized not only to lectin-stained cells in CNV lesions but also to the retina. Compared to non-lasered controls, CCR3 mRNA was significantly increased in laser-treated retina. An intravitreal injection of a CCR3 inhibitor (CCR3i) significantly reduced CNV compared to DMSO or PBS controls. Both CCR3i and a neutralizing antibody to CCR3 increased TUNEL+ retinal cells overlying CNV, compared to controls. There was no difference in cleaved caspase-3 in laser-induced CNV lesions or in overlying retina between CCR3i- or control-treated eyes. Following CCR3i, apoptotic inducible factor (AIF) was significantly increased and anti-apoptotic factor BCL2 decreased in the retina; there were no differences in retinal vascular endothelial growth factor (VEGF). In cultured human Műller cells exposed to eotaxin (CCL11) and VEGF, CCR3i significantly increased TUNEL+ cells and AIF but decreased BCL2 and brain derived neurotrophic factor, without affecting caspase-3 activity or VEGF. CCR3i significantly decreased AIF in RPE/choroids and immunostaining of phosphorylated VEGF receptor 2 (p-VEGFR2) in CNV with a trend toward reduced VEGF. In cultured CECs treated with CCL11 and/or VEGF, CCR3i decreased p-VEGFR2 and increased BCL2 without increasing TUNEL+ cells and AIF. These findings suggest that inhibition of retinal CCR3 causes retinal cell death and that targeted inhibition of CCR3 in CECs may be a safer if CCR3 inhibition is considered as a therapy for neovascular AMD.

[Genotype and phenotype of female Dravet syndrome with PCDH19 mutations]

OBJECTIVE

To explore the genotype and phenotype of female Dravet syndrome (DS) patients with PCDH19 mutations.

METHOD

Clinical data of all DS patients seen at Pediatric Department of Peking University First Hospital from February 2005 to May 2015 were prospectively collected. Genomic DNAs were extracted from the patients and their family members. Female DS patients without SCN1A mutation were enrolled. PCR and Sanger sequencing were performed to identify PCDH19 mutations. Clinical data of DS patients with PCDH19 mutations were summarized.

RESULT

Five different heterozygous PCDH19 mutations were identified in six unrelated patients of 75 SCN1A-negative female DS patients (8%), among whom five patients had de novo mutations and one patient's mutation was inherited from her affected mother. Three missense mutations and two insertion mutations were all located in exon 1. Mean age of onset of the six patients with PCDH19 mutations was 6.8 months (range 5-9 months). Onset of seizures were triggered by fever in four patients, after vaccination in one and without fever in one. Generalized tonic clonic seizure (GTCS) was the first seizure type in four patients and focal seizure with secondary generalized tonic clonic seizures in the remaining two. During the course, all patients presented multiple seizure types including generalized tonic clonic seizures and focal seizures in all six patients, myoclonic seizures in three, absence seizures and atonic seizures in one respectively. In all patients, seizures manifested fever-sensitive and in clusters. Seizures were always in brief duration, in most less than 5 minutes, except one experienced twice status epilepticus triggered by fever. Six patients had development delay after the seizure onset, two with autism spectrum disorder, three with ataxia.

CONCLUSION

PCDH19 is another important gene of DS after SCN1A, mutations mainly occurred de novo. PCDH19 gene mutation should be routinely screened in female DS patients without SCN1A mutation. The clinical features of female DS patients with PCDH19 mutations include that the main seizures types are generalized tonic clonic seizures and focal seizures, seizures occurr in clusters and fever-sensitive, short seizure duration, rare status epilepticus, common development delay and some may manifest autism spectrum disorders.

[The role of smoking and metabolic enzyme polymorphisms in the organic solvent induced chronic encephalopathy]

OBJECTIVE

The organic solvents and other exogenous compounds of metabolic enzymes genetic variation may affect the risk of the toxic effect of organic solvents exposure. Therefore, this research we observed the glutathione transferase M1 and T1 (GSTM1, GSTT1) deletion mutation genotype, two kinds of microsomal epoxide hydrolase (mEPHX) genetic polymorphism, organic solvents exposure and smoking effection in chronic cases of toxic encephalopathy (CTE) correlation.

METHODS

The object was 115 patients who had a long history of organic solvents exposure, were divieded into two groups: CTE (n=83) , no CET (n=32) according to clinical diagnosis. DNA was isolated from patients in white blood cells through the multiple-polymerase chain reaction to determine the loss of GSTM1 and GSTT1 genotype. two kinds of mEPHX polymorphism were analysised through the PCR-RFLP (restriction fragment length polymorphism).

RESULTS

The relative risk has obviously improved when lack of GSTM1 genotypes to CTE (RR=2.35, 95% CI 2.35 0.96). in according to the patient's Smoking condition and classify genotype, patients lack of GSTM1 genotypes had a significantly higher risk CTE than GSTM1+genotype patients (RR=3.13, 95% CI 3.13 1.2) , both mEPHX polymorphisms had nothing to do with an increased risk of CTE.

CONCLUSION

The GSTM1 genotypes played an important role in the organic solvent induced the CTE of susceptibility.it was Influenced by the interaction between smoking at the same time.

Identifying structural flow defects in disordered solids using machine-learning methods

We use machine-learning methods on local structure to identify flow defects-or particles susceptible to rearrangement-in jammed and glassy systems. We apply this method successfully to two very different systems: a two-dimensional experimental realization of a granular pillar under compression and a Lennard-Jones glass in both two and three dimensions above and below its glass transition temperature. We also identify characteristics of flow defects that differentiate them from the rest of the sample. Our results show it is possible to discern subtle structural features responsible for heterogeneous dynamics observed across a broad range of disordered materials.

Temperature-pressure scaling for air-fluidized grains near jamming

We present experiments on a monolayer of air-fluidized beads in which a jamming transition is approached by increasing pressure, increasing packing fraction, and decreasing kinetic energy. This is accomplished, along with a noninvasive measurement of pressure, by tilting the system and examining behavior versus depth. We construct an equation of state and analyze relaxation time versus effective temperature. By making time and effective temperature dimensionless using factors of pressure, bead size, and bead mass, we obtain a good collapse of the data but to a functional form that differs from that of thermal hard-sphere systems. The relaxation time appears to diverge only as the effective temperature to pressure ratio goes to zero.

Vibrational modes identify soft spots in a sheared disordered packing

We analyze low-frequency vibrational modes in a two-dimensional, zero-temperature, quasistatically sheared model glass to identify a population of structural "soft spots" where particle rearrangements are initiated. The population of spots evolves slowly compared to the interval between particle rearrangements, and the soft spots are structurally different from the rest of the system. Our results suggest that disordered solids flow via localized rearrangements that tend to occur at soft spots, which are analogous to dislocations in crystalline solids.

Aberrant expression of chromogranin A, miR-146a, and miR-146b-5p in prostate structures with focally disrupted basal cell layers: an early sign of invasion and hormone-refractory cancer?

Our recent studies have suggested that prostate tumor invasion is triggered by autoimmunoreactions induced focal basal cell layer disruptions (FBCLD) that selectively favor monoclonal proliferation of the overlying progenitors or of a biologically more aggressive cell clone. As circulating chromogranin-A (CgA) levels are found to correlate with tumor progression and the status of hormone refractoriness, our current study attempted to assess whether CgA-positive cells would be preferentially distributed in epithelial structures with FBCLD. Paraffin-embedded specimens from 50 patients with organ-confined prostate cancer were subjected to double immunohistochemical analysis with monoclonal antibodies to basal cells and CgA. From each case, 3-5 randomly selected fields were digitally photographed and the photos were magnified 400% and the numbers of CgA-positive cells in epithelial structures with non-disrupted, focally disrupted, and lost basal cell layer were separately counted. The averaged number of cell for each category was statistically compared with the Pearson's Chi-square test. In addition, morphologically similar structures with and without CgA-positive cell clusters were microdissected from four selected cases and subjected to a comparison of differential micro-RNA expression levels. Our study revealed that, although isolated CgA-positive cells were seen in both the basal cell layer and the luminal cell population in all cases, only 8 cases (16%) harbored large clusters of CgA-positive cells that were concentrated in a given area, in which all or nearly all cells appeared to share a similar morphological and immunohistochemical profile. Microdissected epithelial structures with CgA-positive cell clusters exhibited a more than 5- and 7-fold lower expression of miR-146a and miR-146b-5p than their CgA-negative counterparts. As focal basal cell layer disruptions and the reduction or loss of miR-146a and miR-146b-5p has been documented to correlate with prostate tumor invasion and hormone refractoriness, our findings suggest that aberrant CgA expression in epithelial structures with FBCLD may represent an early sign of these events.

Statistical mechanics of a gas-fluidized particle

Characterization of the microscopic fluctuations in systems that are far from equilibrium is crucial for understanding the macroscopic response. One approach is to use an 'effective temperature'--such a quantity has been invoked for chaotic fluids, spin glasses, glasses and colloids, as well as non-thermal systems such as flowing granular materials and foams. We therefore ask to what extent the concept of effective temperature is valid. Here we investigate this question experimentally in a simple system consisting of a sphere placed on a fine screen in an upward flow of gas; the sphere rolls because of the turbulence it generates in the gas stream. In contrast to many-particle systems, in which it is difficult to measure and predict fluctuations, our system has no particle-particle interactions and its dynamics can be captured fully by video imaging. Surprisingly, we find that the sphere behaves exactly like a harmonically bound brownian particle. The random driving force and frequency-dependent drag satisfy the fluctuation-dissipation relation, a cornerstone of statistical mechanics. The statistical mechanics of near-equilibrium systems is therefore unexpectedly useful for studying at least some classes of systems that are driven far from equilibrium.

[Expression of glucose transporter-1 in endometrial hyperplasia and well-differentiated endometrioid adenocarcinoma]

OBJECTIVE

To investigate the expression of glucose transporter-1 (GLUT1) in endometrial hyperplasia and well-differentiated endometrioid adenocarcinomas.

METHODS

Sixty formalin fixed, paraffin-embedded sections of various endometrial hyperplasia and well-differentiated endometrioid adenocarcinomas were immunostained with rabbit anti-GLUT1 antibody using streptavidin-biotin method.

RESULTS

Two of 12 simple hyperplasia and one of seven complex hyperplasia without atypia were focally positive in metaplastic epithelia. All complex atypical hyperplasia showed positive in varied degree, and 26 among 28 cases of adenocarcinoma were stained positively.

CONCLUSIONS

Overexpression of GLUT1 is a consistent feature of atypical hyperplasia and adenocarcinoma. GLUT1 immunostaining is found to be helpful in distinguishing hyperplasia with atypia from those without atypia.

Serotyping and antimicrobial susceptibility of group B Streptococcus over an eight-year period in southern Taiwan

The increase in penicillin resistance among pneumococci and viridans streptococci and the development of serotype-specific conjugate vaccine have increased the need for knowledge of the antimicrobial susceptibility and the capsular serotypes of group B streptococci. Over an 8-year period, 351 group B streptococcal isolates from southern Taiwan were tested for antimicrobial susceptibility and serotype determination. Eighty-seven percent of the isolates were typeable. Types III (28.5%) and V (27.1%) were the most common serotypes. The occurrence of type V isolates increased with age, while that of type III isolates decreased with age, showing a predominance in children less than 1 year of age. Of 118 isolates from cases of invasive infection, types Ia, Ib, II, III, IV, and V accounted for 12.7, 11.9, 0.8, 33, 1.7, and 26.3%, respectively. Using the agar dilution method, all isolates were found to be susceptible to penicillin, cefotaxime, and vancomycin, 99.4% to ofloxacin, 78.1% to chloramphenicol, 63.2% to azithromycin, 62.6% to erythromycin, 57.3% to clindamycin, and 2.8% to tetracycline. Chloramphenicol resistance was associated with type III isolates (59 of 100, 59%) and erythromycin and azithromycin resistance with type Ib isolates (25 of 33 176%], and 21 of 33 [64%], respectively). Thus, 72% of the isolates from invasive infections were serotype III, V, or Ia, and penicillin remains the drug of choice for treatment or prophylaxis of group B streptococcal infections in southern Taiwan, despite the high prevalence of penicillin resistance among Streptococcus pneumoniae and viridans streptococci.

Elastically driven linker aggregation between two semiflexible polyelectrolytes

The behavior of mobile linkers connecting two semiflexible charged polymers, such as polyvalent counterions connecting DNA or F-actin chains, is studied theoretically. The chain bending rigidity induces an effective repulsion between linkers at large distances while the interchain electrostatic repulsion leads to an effective short-range interlinker attraction. We find a rounded phase transition from a dilute linker gas where the chains form large loops between linkers to a dense disordered linker fluid connecting parallel chains. The onset of chain pairing occurs within the rounded transition.

Effect of nonzero chain diameter on "DNA" condensation

We present a simple model to investigate the effect of chain diameter on multivalent-counterion-induced attractions between two charged chains. In our minimal model, the chains are rigid rods of diameter D with a uniform charge density on the surface, and the counterions are point ions. As a function of the separation between two rods, we find a repulsive barrier in the free energy whose height increases with D. We have also explored the effect of counterion valency Z on the interaction. For parameters characteristic of DNA, we find that a minimum valency of Z=3 is required to produce condensation. We also find that the shape of the potential is fairly insensitive to Z for Z>/=3. These results are consistent with experimental observations of DNA condensation.

Force Distributions near Jamming and Glass Transitions

We calculate the distribution of interparticle normal forces P(F) near the glass and jamming transitions in model supercooled liquids and foams, respectively. P(F) develops a peak that appears near the glass or jamming transitions, whose height increases with decreasing temperature, decreasing shear stress and increasing packing density. A similar shape of P(F) was observed in experiments on static granular packings. We propose that the appearance of this peak signals the development of a yield stress. The sensitivity of the peak to temperature, shear stress, and density lends credence to the recently proposed generalized jamming phase diagram.

Statistics of shear-induced rearrangements in a two-dimensional model foam

Under steady shear, a foam relaxes stress through intermittent rearrangements of bubbles accompanied by sudden drops in the stored elastic energy. We use a simple model of foam that incorporates both elasticity and dissipation to study the statistics of bubble rearrangements in terms of energy drops, the number of nearest neighbor changes, and the rate of neighbor-switching (T1) events. We do this for a two-dimensional system as a function of system size, shear rate, dissipation mechanism, and gas area fraction. We find that for dry foams, there is a well-defined quasistatic limit at low shear rates where localized rearrangements occur at a constant rate per unit strain, independent of both system size and dissipation mechanism. These results are in good qualitative agreement with experiments on two-dimensional and three-dimensional foams. In contrast, we find for progessively wetter foams that the event size distribution broadens into a power law that is cut off only by system size. This is consistent with criticality at the melting transition.

Effect of ordering on spinodal decomposition of liquid-crystal/polymer mixtures

Partially phase-separated liquid-crystal/polymer dispersions display highly fibrillar domain morphologies that are dramatically different from the typical structures found in isotropic mixtures. To explain this, we numerically explore the coupling between phase ordering and phase-separation kinetics in model two-dimensional fluid mixtures phase separating into a nematic phase, rich in liquid crystal, coexisting with an isotropic phase, rich in polymer. We find that phase ordering can lead to fibrillar networks of the minority polymer-rich phase.

Counterion-mediated, non-pairwise-additive attractions in bundles of like-charged rods

Stiff polyelectrolyte chains, such as DNA, can attract each other in solution even though they have the same sign of charge. The attractions are mediated by multivalent counterions, which lead to an effective interaction at the two-chain level that is attractive at short range and repulsive at long range. However, the effective interchain interactions are not pairwise additive. We present a formulation that allows theoretical treatment of the many-chain problem without assuming pairwise additivity. We show that a bundle of chains held together by counterion-mediated attractions can be described in terms of a bulk and surface free energy, and discuss the temperature dependence of the attraction.

Rickettsia helvetica in Ixodes ricinus ticks in Sweden

In the present study further characterization of the amplified sequence of the citrate synthase gene of the spotted fever group Rickettsia isolated from Ixodes ricinus ticks in Sweden showed that it has 100% homology with the deposited sequence of the citrate synthase gene of Rickettsia helvetica. The restriction fragment length polymorphism (RFLP) pattern of an amplified 382-bp product of the citrate synthase sequence, defined by primers RpCS877 and RpCS1258, yielded fragments for our isolate that could be visualized as a double band that migrated at approximately 44 bp, another double band at 85 bp, and a single band at nearly 120 bp after digestion with the restriction enzyme AluI. When calculating a theoretical PCR-RFLP pattern of the sequence of the citrate synthase gene of R. helvetica from the known positions where the AluI enzyme cuts, we arrived at the same pattern that was obtained for our isolate, a pattern distinctly different from the previously published PCR-RFLP pattern for R. helvetica. Investigation of 125 living I. ricinus ticks showed a higher prevalence of rickettsial DNA in these ticks than we had found in an earlier study. Rickettsial DNA was detected by amplification of the 16S rRNA gene, for which a seminested primer system consisting of two oligonucleotide primer pairs was used. Of the 125 ticks, some were pooled, giving a total of 82 tick samples, of which 20 were found to be positive for the rickettsial DNA gene investigated. When considering the fact that some of the positive samples were pooled, the minimum possible prevalence in these ticks was 20 of 125 (16%) and the maximum possible prevalence was 46 of 125 (36.8%). These prevalence estimates conform to those of other studies of spotted fever group rickettsiae in hard ticks in Europe.

20-[18F]fluoromibolerone, a positron-emitting radiotracer for androgen receptors: synthesis and tissue distribution studies

To develop an androgen receptor-based, positron-emitting imaging agent for prostate tumors, we have prepared 20-fluoromibolerone (F-Mib) and evaluated its tissue distribution. This compound was synthesized in eight steps from 7 alpha-methyl-19-nortestosterone, with fluorine introduced in the penultimate step by fluoride ion displacement on a spirocyclic sulfate. Fluoromibolerone was obtained in 9%-19% radiochemical yield (decay corrected), at 1.5 hr after bombardment, with an effective specific activity of 217-283 Ci/mmol. The relative binding affinity of F-Mib is 53 (versus R1881 = 100 or mibolerone = 118). In tissue distribution studies in diethylstilbestrol-treated male rats, 18F-Mib demonstrates high target/tissue uptake efficiency and selectivity: the prostate uptake at 0.5 hr and 4 hr is 1.0%-1.3% injected dose/gram tissue (ID/g) and 0.5%-0.6% ID/g, respectively; the prostate-to-blood and the prostate-to-muscle (non-target) ratios are both ca. 4 at 0.5 hr, and increase to ca. 12 by 4 hr after injection. The observed distribution of 18F-Mib suggests that it may be useful for in vivo imaging of prostatic tumors in man by positron emission tomography.