[Incidence of diabetes and influencing factors in HIV-infected individuals after antiretroviral therapy in Dehong Dai and Jingpo Autonomous Prefecture]

Objective: To understand the incidence of diabetes and influencing factors, the trend of FPG change and risk for mortality in HIV-infected individuals after antiretroviral therapy (ART) in Dehong Dai and Jingpo Autonomous Prefecture (Dehong). Methods: The HIV/AIDS treatment database was collected from China Information System for Disease Control and Prevention. This retrospective cohort study was conducted in HIV-infected individuals with access to ART in Dehong during 2004-2020.The Cox proportional hazard regression model was used to analyze the incidence density of diabetes, the influencing factors and risk for mortality in HIV-infected individuals with access to ART, mixed linear effects model was used to analyze the trend of FPG change and predict FPG in those with different glucose metabolic status at baseline survey. Statistical analysis was performed using software SAS 9.4. Results: A total of 8 763 HIV-infected individuals were included, in whom 8 432 (96.2%) had no diabetes, 331 had diabetes. The incidence density of diabetes was 2.31/1 000 person years. Multivariate Cox proportional hazard regression analysis revealed that 30- 59 years old, BMI ≥24.0 kg/m2, Efavirenz (EFV) based initial treatment regimen and impaired fasting glucose (IFG) at baseline survey were significantly and positively associated with incidence of diabetes. Mixed effect model revealed that FPG was positively correlated with the duration of ART, age and baseline FPG. Suffering from diabetes was a risk factor for mortality in HIV-infected individuals both at baseline survey and during follow-up. Conclusions: The risk for diabetes increased in HIV-infected individuals who were 30-59 years old, baseline BMI ≥24.0 kg/m2, received EFV based initial treatment, and IFG in HIV-infected individuals after antiretroviral therapy in Dehong, 2004-2020. It is important to pay close attention to their blood glucose, and patients with high blood glucose should receive treatment as early as possible.

[Attention should be paid to the application of regional citrate anticoagulation in blood purification]

Compared with traditional low-molecular-weight heparin anticoagulation or non-anticoagulant hemodialysis, regional citrate anticoagulation (RCA) has emerged as a promising anticoagulant method considering its satisfactory efficacy, reduced incidence of bleeding, extended life of the dialyzer and increased removal of the toxin. RCA has received more and more attention in recent years which contributes as a first-line anticoagulant regimen for continuous renal replacement therapy, and it gradually gains wide clinical application in maintenance hemodialysis (MHD). In addition, RCA has been reported to be successfully used in plasma exchange and hemoperfusion. This article elaborates on mechanism of RCA and the problems in clinical application, in order to further expand the application of RCA and improve the effect of blood purification in the future.

[Mechanism and clinical significance of HBV reactivation after anti-HCV therapy]

Direct-acting antivirals (DAAs) can strongly inhibit the replication of hepatitis C virus (HCV) and effectively clear the infection, but it may cause hepatitis B virus (HBV) reactivation, leading to severe liver damage and fulminate hepatitis in patients with HCV/HBV coinfection. In this review, we summarized the different replication process of HCV and HBV in infected hepatocytes and consequent innate immune response, and then discussed the molecular mechanism and clinical significance of HBV reactivation, and put forward the clinical precaution.

[Identification of the feature of immune cells infiltration in inherited renal carcinoma with von Hippel-Lindau syndrome]

Objective: To investigate the feature of immune cells infiltration in inherited renal carcinoma with von Hippel-Lindau (VHL) syndrome and their relationship with clinicopathological characteristics and prognosis. Methods: The samples were collected from patients with VHL syndrome renal carcinoma who were diagnosed and treated surgically at the Department of Urology, Peking University First Hospital from 2010 to 2019. RNA-Seq was performed on 6 pairs of VHL syndrome renal carcinoma and adjacent normal tissues. To identify the specific infiltrated immune cells, RNA-Seq data was converted into the infiltration data of 14 types of immune cells using the TIP tool. Immunohistochemical staining was used to verify the expression of the markers of these specific infiltrated immune cells in the paraffin sections of 54 paired VHL syndrome renal carcinoma and adjacent normal tissues, and to analyze their relationship with clinicopathological characteristics and prognosis. Results: Compared with adjacent normal tissues, CD4 Naive infiltration level was significantly down-regulated (0.289±0.009 vs 0.200±0.012,P<0.001) and CD4 Memory infiltration level was significantly up-regulated (0.123±0.014 vs 0.222±0.016,P<0.001) in VHL syndrome renal carcinoma. Immunohistochemical staining results showed that CD45RA (a CD4 Naive cell marker) expression was significantly reduced (50.9±1.9 vs 15.6±0.9,P<0.001) and CD45RO (a CD4 Memory cell marker) expression was significantly increased (22.2±1.1 vs 80.8±4.3,P<0.001) in VHL syndrome renal carcinoma. Besides, lower CD45RA expression and higher CD45RO expression were associated with higher histological grade, advanced tumor stage and shorter disease-free survival (all P<0.01). In addition, CD45RA expression was positively correlated with VHL expression (r=0.693 3, P<0.000 1) and CD45RO expression was negatively correlated with VHL expression (r=-0.609 0, P<0.000 1). Conclusions: This study found that CD4 Naive and CD4 Memory cells may be differentially infiltrated immune cells in VHL syndrome renal carcinoma, and their infiltration levels were associated with the expression of VHL and the prognosis of patients.

[Clinicopathological and prognostic characteristics of clear cell papillary renal cell carcinoma]

Objective: To analyze the epidemiological, clinicopathological and prognostic characteristics of clear cell papillary renal cell carcinoma (CCPRCC) based on Chinese patient population. Method: Patients with renal cell carcinoma diagnosed at Peking University First Hospital from June 2016 to June 2020 were included in this study based on the inclusion and exclusion criteria. All cases were grouped according to CCPRCC, clear cell renal cell carcinoma (ccRCC), and papillary renal cell carcinoma (pRCC), and the general clinical, postoperative pathological and follow-up data of the patients were retrospectively analyzed. Result: A total of 18 CCPRCC patients were enrolled in this study, accounting for 0.44% (18/4 110) of the postoperative pathologically confirmed renal cell carcinoma cases in our hospital during this time period. The age range of the included patients was 28-86 years old, with a median age of 49.5 years old. There were 11/18 males and 7/18 females. All CCPRCC patients had no family history of renal malignant tumors. Among them, only one patient with CCPRCC had related clinical symptoms, that was intermittent waist and abdomen pain, while the other 17 cases were found by physical examination without any related symptoms. Compared with ccRCC and pRCC, there was no significant difference in their end stage renal disease history(χ²_ccRCC=0.291, χ²_pRCC=1.161,all P>0.05). The maximum diameter of CCPRCC tumor was smaller than pRCC (χ²=-2.280,P =0.027) but not significantly different from ccRCC (χ²=-0.579,P =0.565). The majority of patients with CCPRCC were in pT1, their pathological stage was earlier than the other two types, and their overall survival was better than ccRCC and pRCC (P<0.05). Conclusion: CCPRCC is a type of renal cell carcinoma with unique epidemiology, clinicopathology and prognostic characteristics. Patients with this subtype have an earlier clinical stage and a better prognosis than ccRCC and pRCC.

[Current status of hyperkalemia in dialysis patients in China]

Objective: To investigate the prevalence and associated factors of hyperkalemia in dialysis patients. Methods: Patients underwent hemodialysis (HD) and peritoneal dialysis (PD) from multi-center databases were recruited from January 2017 to December 2019, and those aged ≥18 years and with dialysis duration ≥3 months were included to analyze the prevalence and related factors of hyperkalemia. Results: A total of 12 364 patients were enrolled in the study, and 6 836 cases were men. The average age of the patients was (51±15) years. Among these patients, 4 230 cases underwent HD while 8 134 received PD. Hyperkalemia was detected in 20.7% (2 554/12 364) of the patients while hypokalemia was found in 17.0%(2 102/12 364) of the patients. Multivariate logistic regression showed that HD (OR=2.25, 95%CI: 1.54-3.30), diabetes mellitus (DM) (OR=1.65, 95%CI: 1.17-2.32), high body mass index (BMI) (OR=1.06, 95%CI: 1.03-1.09), high levels of serum albumin (OR=1.04, 95%CI: 1.01-1.07) and phosphorus (OR=3.12, 95%CI: 2.44-4.00), low levels of serum bicarbonate (OR=0.89, 95%CI: 0.87-0.92), triglycerides (OR=0.76, 95%CI: 0.68-0.85) and creatinine (OR=0.95, 95%CI: 0.90-0.99), usage of angiotensin converting enzyme inhibitor/Angiotensin Ⅱ receptor antagonist (ACEI/ARB, OR=1.38, 95%CI: 1.11-1.72) and beta-blocker (OR=1.32, 95%CI: 1.07-1.64) were associated with hyperkalemia. Conclusions: Hyperkalemia occurred in 20.7% of the dialysis patients. HD, DM, high BMI, high levels of serum albumin and phosphorus, low levels of serum bicarbonate, triglycerides and creatinine, use of ACEI/ARB were associated with hyperkalemia.

[A retrospective cohort study of incidence of anemia and risk factors in HIV/AIDS patients with access to antiretroviral therapy in Dehong Jingpo and Dai Autonomous Prefecture in Yunnan province, 2004-2018]

Objective: To investigate the incidence of anemia and risk factors in HIV/AIDS patients with access to antiretroviral therapy (ART) during 2004-2018 in Dehong Jingpo and Dai Autonomous Prefecture (Dehong). Methods: A retrospective cohort study was conducted in HIV/AIDS patients receiving ART in Dehong during 2004-2018 based on the data extracted from the National HIV/AIDS antiretroviral therapy database. Cox proportional risk model was used to analyze the factors associated with the incidences of anemia and moderate or severe anemia in the HIV/AIDS patients. And the piecewise linear mixed-effects model was used to depict the trajectory of hemoglobin changes over time after initiating ART according to baseline level. Results: A total of 8 044 HIV/AIDS patients were included, in whom 6 337 (78.8%) were without anemia at baseline survey and had a median follow up time of 4.43 (P₂₅, P₇₅: 1.50, 6.71) years. The median follow up time for 1 291 new anemia cases and 293 new moderate or severe anemia cases was 0.16 (P₂₅, P₇₅: 0.07, 1.99) years and 0.48 (P₂₅, P₇₅:0.09, 2.97) years, respectively. The incidence rate of anemia and moderate or severe anemia was 4.40 per 100 person-years and 0.41 per 100 person-years respectively. In multivariable Cox regression analysis, older age, being female, being in Dai and Jingpo ethnic group, baseline BMI <18.5 kg/m², baseline CD4⁺T lymphocyte cell counts (CD4) <200 cells/μl, and zidovudine (AZT) -based initial treatment regimen were factors significantly and positively associated with incidence of anemia after treatment. Factors as being female, being in Dai ethnic group, baseline BMI <18.5 kg/m², mild baseline anemia, and AZT-based initial treatment regimen were significantly and positively associated with incidence of moderate or severe anemia after treatment. Conclusion: The risk for anemia was higher in HIV/AIDS patients with specific characteristics, such as age ≥60 years , being female, being in Dai and Jingpo ethnic groups, lower BMI, CD4 <200 cells/μl, and treatment of AZT, after initiation of ART in Dehong during 2004-2018. Additional efforts are needed to strengthen the screening, prevention and treatment of anemia in this population.

[Analysis of the clinical perinatal characteristics of 226 patients with Prader-Willi syndrome in China]

Objective: To enhance the early recognition of Prader-Willi syndrome by summarizing the clinical characteristics of Prader-Willi syndrome (PWS) during perinatal period. Methods: Through a nationwide cross-sectional study in the Department of Pediatrics, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences,226 children diagnosed as PWS by molecular genetics were recruited from September 2019 to March 2020. Clinical data including fetuses Age, birth weight, fetal movement, fetal position, amniotic fluid, mode of bith, crying, muscle tension, feeding, and cryptorchidism were collected to analyze the clinical characteristics of Chinese PWS patients in the perinatal period, and according to the mode of birty, birth weight and genotypes to perform subgroup analysis. The clinical manifestations of different subtypes were statistically analyzed by t test, χ² test or Mann-Whitney U test. Results: Among the 226 PWS patients, 120 were males, and 106 were females. Among them, 100 (44.2%) patients were small for gestational age. Decreased fetal movement was the most common manifestation 202 cases (89.4%) during pregnancy, and other manifestations included polyhydramnios 71 cases (31.4%) and abnormal fetal position 58 cases (25.7%). One hundred and eighty-five (81.9%) patients were delivered by cesarean section and the frequency of abnormal fetal position was significantly higher (30.8%(57/185) vs. 2.4%(1/41),χ²=14.161,P<0.01). As for abnormal manifestations after birth included hypotonia 221 cases (97.8%),220 cases (97.3%) showing weak crying, 116 cases among the total 120 males patients (96.7%) wanifested with cryptordnildism and 206 feeding difficulties (91.2%). In terms of genetic subtype, most of them (184/226, 81.4%) had a paternal deletion, while maternal age (35±5 vs. 29±5, t=-6.591, P<0.01) and the frequency of polyhydramnios (47.6% (20/42) vs. 27.7% (51/185), χ²=6.286, P=0.012) were significantly higher in the non-deletion group. Conclusions: The main manifestations of PWS patients during the perinatal period are hypotonia, weak crying, feeding difficulties, decreased fetal movement, cryptorchidism and those patients are more likely to be born by cesarean section. In newborns with these characteristics, pediatricians should be aware of the possibility of PWS. In terms of the relationship between genotypes and phenotypes, polyhydramnios is more frequently observed in the non-deletion group.

[The association between the whole blood riboflavin level and the occurrence, development and prognosis of esophageal squamous cell carcinoma]

Objective: To investigate the association between the whole blood riboflavin level and the occurrence, development and prognosis of esophageal squamous cell carcinoma (ESCC) in China. Methods: From March 2014 to September 2018, ESCC patients from three hospitals (the Affiliated Hospital of Medical College of Shantou University, Shantou Central Hospital in Southern Chaoshan area and First Affiliated Hospital of Zhengzhou University in Northern Taihang Mountain) were selected as a case group; non-esophageal patients who had a physical examination were selected as a control group. The case and control group were paired by age (±5 years) and a 1:1 ration. A total of 1 528 subjects were enrolled including 764 patients in the case group and 764 patients in the control group. About 3-5 ml venous blood samples were collected, and the erythrocyte glutathione reductase activity coefficient (GRAC) was measured to assess the whole blood riboflavin level. A multivariate conditional logistic regression model was used to analyze the association between the GRAC and the risk of ESCC. The association between the GRAC and the prognosis of ESCC was analyzed by using Cox proportional risk regression model based on 288 patients with complete survival data. They were divided into two groups, the high GRAC group (GRAC≥7.87) group and the low GRAC group (GRAC<7.87) according to the strongest correlation between the total survival time, survival outcome and GRAC (GRAC=7.87). Results: Among the 1 528 patients, 958 patients were from Southern Chaoshan area, including 479 patients in the case group with an average age about (59.90±9.34) years and 479 patients in the control group with an average age about (59.55±8.77) years. Other 570 patients were from Northern Taihang Mountain area, including 285 patients in the case group with an average age (58.39±5.19) years and 285 patients in the control group with an average age about (58.74±4.57) years. The multivariate conditional logistic regression showed that the OR (95%CI) of the GRAC and the risk of ESCC was 1.009 (0.998-1.019). The Cox proportional hazard regression model analysis showed that the HR (95%CI) of the high GRAC group was 1.712 (1.034-2.824) compared with the low GRAC group in the 50-70 years group. Conclusion: The whole blood riboflavin level might not be associated with the occurrence of ESCC. The high whole blood riboflavin level would be more beneficial to the prognosis of ESCC patients aged 50-70 years.

Mir20a/106a-WTX axis regulates RhoGDIa/CDC42 signaling and colon cancer progression

Wilms tumor gene on the X chromosome (WTX) is a putative tumor suppressor gene in Wilms tumor, but its expression and functions in other tumors are unclear. Colorectal cancer (CRC) is the third leading cause of cancer-related deaths in women and the second leading cause in men in the United States. We demonstrated that WTX frequently lost in CRC which was highly correlated with cell proliferation, tumor invasion and metastasis. Mechanistically, WTX loss disrupts the interaction between RhoGDIα and CDC42 by losing of the binding with RhoGDIα and triggers the activation of CDC42 and its downstream cascades, which promotes CRC development and liver metastasis. The aberrant upregulation of miR-20a/miR-106a were identified as the reason of WTX loss in CRC both in vivo and in vitro. These study defined the mechanism how miR-20a/miR-106a-mediated WTX loss regulates CRC progression and metastasis, and provided a potential therapeutic target for preventing CRC progression.

[Functional rhinoplasty under nasal endoscope]

Objective:At different times and cultural background,people have different definition of beauty.With the improvement of economic level and culture quality,people are becoming more and more recognition of nasal appearance and function are equally important.Even the importance of the function of the nasal is higher than the importance of shape of the nose. Concurrent rhinoplasty (nasal dorsum and lateral nasal wall reduction) and functional sinus surgery (nasal septum reconstructory, middle turbinate,inferior turbinate surgery even extended to the nasal cavity expansion tecunhnique, sinusitis surgery) with endoscopic surgical surgical methods were discussed.Method:The study included 20 patients with deformed functional endoscopic rhinoplasty, 2010-2015 in Beijing Tongren Hospital,of ages 16-53, male 14 cases,female 6 cases, 11cases had history of trauma, all of 20 patients have unilateral nasal plugging. Operating methods, 17 patients were performed nasal endoscopic septoplasty and rhinoplasty at the same time. One case cocurrent endoscopic rhinodacryocystostomy.Two cases were performed Nasal endoscopic sinus operation. Only 5 cases use silica gel prosthesis, 15 cases use autologous cartilage in functional rhinoplasty.Result:Twenty patients compared with performed rhinoplasty,nasal septum reconstructory,middle turbinate,inferior turbinate surgery,nasal cavity expansion,sinusitis surgery separately,surgery is better,no other complicationgs occurred.Actually decredsed the number of surgical treatment and hospitalization expenses.Conclusion:Functional endoscopic rhinoplasty,over the same period it solved the nasal shape and nasal ventilation function.To avoid impact on ventilation function in the process of the rhinoplasty.Implements the unification of beauty and function.Reduce the surgical treatment of times and cost.No other complication compared to convertional surgery,high feasibility.

SPHK2 protein expression, Ki-67 index and infiltration of tumor-associated macrophages (TAMs) in human glioma

INTRODUCTION

Sphingosine kinases (SPHKs), the Ki-67 index and tumor-associated macrophages (TAMs) are associated with diverse human malignancies, including glioma. SPHK2, a subtype of SPHKs, has not been assessed in glioma or correlated with the Ki-67 index or TAM infiltration. We tested the hypothesis that expression of SPHK2 correlates with the Ki-67 index and TAM infiltration in patients with glioma.

MATERIALS AND METHOD

Western blot analysis was performed on protein lysates prepared from human astrocyte (HA) and glioma cell lines. Immunofluorescence was used to determine the subcellular location of SPHK2 protein in glioma cells. Next, immunohistochemistry was employed to analyze the correlations among SPHK2, Ki-67, CD68, and CD206 in 11 non-neoplastic brain tissues and 60 glioma tissues. All slides were evaluated under ×400 magnification, and the ratio of positively stained cells to the total number of cells was calculated for analysis.

RESULTS

SPHK2, CD68 and CD206 were all increased in glioma tissues compared to non-neoplastic brain tissues, but there were no differences between WHO grades of glioma. Ki-67 was highest in WHO grade IV tumors and lowest in non-neoplastic brain tissues, and all between-group differences were statistically significant. Moreover, SPHK2 expression was positively correlated with the Ki-67, CD68 and CD206 indexes. Finally, the CD68 and CD206 indexes were both associated with the Ki-67 index.

CONCLUSION

SPHK2 protein expression, the Ki-67 index and TAM infiltration in human glioma tissue were reported in this study for the first time. SPHK2 was positively associated with TAM infiltration and glioma proliferation. Mechanistically, SPHK2 may promote glioma growth by stimulating TAMs to polarize M2-type macrophages.

[Effect of transient ischemic attack on early neurological deterioration in patients with ipsilateral ischemic stroke]

Objective: To explore the effect of anterior circulation transient ischemic attack (TIA) on early neurological deterioration (END) in patients with ipsilateral ischemic stroke and its mechanism. Methods: (1) One hundred and thirteen patients with ipsilateral ischemic stroke and 36 healthy volunteers (healthy control group) in Neurology Department of Tianjin Medical University General Hospital from November 2014 to July 2015 were recruited into this study. According to whether got TIA before ischemic stroke, patients were divided into simple ischemic stroke group (CI group, n=87) and TIA-CI group (n=26). Their END, NIHSS score, 3-month mRS score, infarct size, serum hs-CRP and other risk factors were compared. (2) The peripheral blood mononuclear cells (PBMCs) were extracted from peripheral blood of TIA-CI group and CI group at 24 h, the 3 th day, the 7 th day and 12th day after ischemic stroke onset. At the same time, PBMCs of control group were collected. Western blot was carried out to evaluate the expression of nuclear factor-κB (NF-κB). Immunofluorescence was used to detect the cytoplasmic-to-nuclear shuttling of NF-κB. Results: (1) The incidence of END, NIHSS score at discharge, 3-month mRS score and serum hs-CRP level were significantly lower whereas the infarct size was significantly smaller of TIA-CI group than CI group (11.5% vs 31.0%, 1.9±2.3 vs 3.3±3.7, 0.9±0.8 vs 1.8±1.8, 1.1(0.3, 2.5) cm(3) vs 2.4(0.5, 22.8) cm(3,) (2.5±3.2) mg/L vs (6.2±3.2) mg/L, all P<0.05) . hs-CRP was positively correlated with END (r=0.311, P<0.05). (2) Expression of NF-κB: ① Compared with control group, the NF-κB expression increased first and then decreased in both of the two patient groups, and it decreased earlier in TIA-CI group than CI group.②In each time point, NF-κB expression of TIA-CI group was lower than CI group(t=1.754, P<0.05; t=1.858, P<0.05; t=0.609, P<0.05; t=0.519, P<0.05). (3) Activity of NF-κB: Most of NF-κB were inactivation and located in cytoplasm of control group. NF-κB of TIA-CI group and CI group was activated and translocated from cytoplasm into nuclear at the 24 h and 3 th day after ischemic stroke. At the 7 th day and 12th day, the accumulation of NF-κB in nuclear decreased and most of them located in cytoplasm in TIA-CI group, whereas most of NF-κB still located in nuclear in CI group. The activated station of NF-κB lasted shorter in TIA-CI group than CI group. Conclusions: TIA can reduce the incidence of END in patients of ipsilateral ischemic stroke. Its protective effect may relate with the inhibition of inflammation which induced by NF-κB.

Establishing a comprehensive genetic diagnosis strategy for hemophilia B and its application in Chinese population

INTRODUCTION

To reduce the incidence of hemophilia B (HB) which with no complete cure currently, prenatal diagnosis and preimplantation genetic diagnosis (PGD) are effective and feasible means. However, previous studies about genetic diagnosis in HB mostly just focused on the detection of patients and carriers. Here, we established a comprehensive genetic diagnosis strategy for HB and worked it out in Chinese population. The strategy includes the detection of patients and carriers, prenatal diagnosis, and PGD.

METHODS

Seven unrelated HB families from Chinese population involved in this study. Firstly, probands and available members were carried out coagulation laboratory assays, and the clinical information has been recorded. Secondly, we used DNA direct sequencing to screen the whole FIX gene of them. The pathogenicity of novel mutations was verified according to 2015 ACMG-AM guidelines. For prenatal diagnosis, a mix of DNA direct sequencing and STR linkage analysis was employed. To explore a better PGD protocol, Karyomapping was first applied in PGD of HB, comparing with conventional PCR-based methods.

RESULTS

Six different pathogenic mutations including 1 novel duplication (c.660_661dup ATCA) were identified. The results of prenatal diagnosis were consistent with birth outcomes. In the PGD case, 4 of 11 embryos were confirmed to be normal and one of them was transferred and led to a healthy birth.

CONCLUSIONS

The established genetic diagnosis strategy for HB in our study was comprehensive and well applied in clinic practice. Besides, we recommended that DNA direct sequencing combined with Karyomapping was a better PGD protocol.

[Drug resistance and influencing factors in adult AIDS patients receiving antiretroviral treatment in Dehong, Yunnan province]

OBJECTIVE

To investigate the incidence of drug resistance in adult AIDS patients receiving antiretroviral treatment(ART)and influencing factors in Dehong prefecture, Yunnan province during 2012-2014.

METHODS

For this cohort study, all the AIDS patients aged over 15 and receiving ART in Dehong were screened for HIV drug resistance in 2012, and 3 715 patients who had received ART for more than 6 months were enrolled for 12 months and 24 months follow up.

RESULTS

Among the 3 715 patients, 56.6% were males, 72.6% were aged 26-45 years and 76.0% were married. The main treatment regimen was nevirapine(NVP)+ lamivudine(3TC)+ zidovudine(AZT)(38.2%). A total of 3 556 patients(95.7%)received at least one viral load testing during the two years follow-up, among them 253(7.1%)patients had VL≥1 000 copies/ml, in which 211(83.4%)received drug resistance related gene mutation testing, the results indicated that the drug resistance developed in 52 and 39 patients in 2013 and 2014(1.43 per 100 person years and 0.88 per 100 person years)respectively. The overall HIV drug incidence was 1.13 per 100 person years. Multivariate regression analysis indicated that age ≤25 years, to be infected through drug use, treatment regimen as D4T+ 3TC +NVP and baseline CD4(+) T cells ≤200 cells/μl were the risk factor of HIV drug resistance. Eleven HIV gene subtypes were detected in the 82 patients with newly developed drug resistance, CRF_BC was predominant(31.7%), followed by CRF01_AE(22.0%)and C(19.5%). Ten patients were infected with mixed subtypes of CRF_BC/B', CRF_BC/CRF_01B and CRF_BC/C. Most of the 82 patients were resistant to NRTIs and NNRTIs, the main mutation loci were M184V and K103N.

CONCLUSIONS

The incidence of drug resistance in adult AIDS patients receiving ART was relatively low in Dehong. However, it is necessary to conduct the health education in young people and drug users to improve the treatment compliance and strengthen the surveillance for HIV drug resistance.

[Clinical analysis of preimplantation genetic diagnosis with HLA matching for beta-thalassemia]

OBJECTIVE

To investigate the efficacy and feasibility of preimplantation genetic diagnosis(PGD)with human leukocyte antigen(HLA)matching for beta-thalassemia.

METHODS

A total of 43 referred beta-thalassemia couples, with at least on child in need of hematopoietic stem cell transplantation(HSCT), underwent PGD for HLA matching at the First Affiliated Hospital of Sun Yat-sen University from 2010 to 2015. PGD cycles of these couples were retrospectively analyzed, and 15 infants born from PGD-HLA were followed up.

RESULTS

A total of 84 oocyte retrieval cycles were performed, providing 14±7 oocytes per cycle. Fifty nine embryos biopsied cycles were done, including 24 cleavage stage and 35 blastocyst stage biopsy cycles. In cleavage stage, 259 embryos were biopsied, 93.4%(242/259)of them with conclusive molecular diagnosis, and the percentage of unaffected embryos(normo-homozygote and heterozygote)was 71.4%(185/259). The percentage of HLA matched unaffected embryos was 9.3%(24/259). In blastocyst stage, 306 embryos were biopsied, while 93.8%(287/306)of them were conclusive, and the percentage of unaffected embryos was 70.6%(216/306). The percentage of HLA matched unaffected embryos in blastocyst stage biopsy was 14.4%(44/306), which was higher than in cleavage stage biopsy(P< 0.05). Forty three female carriers underwent 48 embryo transfer cycles including 3 fresh and 45 frozen-thawed embryo transfer cycles. Three fresh embryo transfer cycles were done after cleavage stage biopsy, resulted in a birth of healthy twins born at 36 weeks' gestation. All the embryos were frozen after blastocyst biopsied. Totally, 54 frozen-thawed embryos that were transferred in 45 frozen-thawed embryo transfer cycles included 25 embryo from cleavage stage biopsy and 29 embryo from blastocyst stage biopsy, and 42 of them were HLA matched. Clinical pregnancy rate and implantation rate per cycle in frozen-thawed embryo transfer were 38%(17/45)and 37%(20/54)respectively. A total of 15 infants were born, 2 were from a fresh embryo transfer cycle, and 13 were from frozen-thawed embryo transfer cycles. RESULTS of prenatal diagnosis from delivered cases were matched to that of PGD. Four sick children have been cured by HSCT from these HLA matched born siblings.

CONCLUSION

PGD with HLA matching is an established method for conceiving a child who may donate hematopoietic stem cells to save an ill sibling.

[Brain plastic alterations in subjects with chronic right-sided sensorineural hearing loss: a resting-state MRI study]

OBJECTIVE

To investigate the nodal properties and reorganization of whole-brain functional network in subjects with severe right-sided SNHL.

METHODS

From June 2012 to June 2013, a total of 19 patients with severe right-sided SNHL were collected from Zhongda Hospital or the recruitment advertising along with 31 healthy controls.Based on the graph-theoretical analysis, the whole-brain functional networks were constructed using the BOLD-fMRI data of all subjects.Two sample two-tailed t-tests were used to investigate the differences between two groups in nodal metrics, such as node degree, node betweenness, node global efficiency and node local efficiency.All metrics were corrected by multiple comparisons.Partial correlation analysis was used to estimate the relationship between the significant metrics and the duration or severity of hearing loss.

RESULTS

The right-sided SNHL showed significantly increased betweenness centrality in left supramarginal gyrus and right fusiform.However, other nodal parameters showed no statistical difference.Besides, patients exhibited no significant association between the altered metrics and clinical variables.

CONCLUSION

Alterations of local topological properties may underlie cerebral cross-modal plastic reorganization in visual or speech-related regions in severe right-sided SNHL patients.

Mechanism of phosphoryl transfer by nucleoside diphosphate kinase pH dependence and role of the active site Lys16 and Tyr56 residues

Nucleoside diphosphate (NDP) kinase phosphorylates nucleoside diphosphates with little specificity for the base and the sugar. Although nucleotide analogues used in antiviral therapies are also metabolized to their triphosphate form by NDP kinase, their lack of the 3'-hydroxyl of the ribose, which allows them to be DNA chain terminators, severely impairs the catalytic efficiency of NDP kinase. We have analyzed the kinetics parameters of several mutant NDP kinases modified on residues (Lys16, Tyr56, Asn119) interacting with the gamma-phosphate and/or the 3'-OH of the Mg2+-ATP substrate. We compared the relative contributions of the active-site residues and the substrate 3'-OH for point mutations on Lys16, Tyr56 and Asn119. Analysis of additional data from pH profiles identify the ionization state of these residues in the enzyme active form. X-ray structure of K16A mutant NDP kinase shows no detectable rearrangement of the residues of the active site.

3'-Phosphorylated nucleotides are tight binding inhibitors of nucleoside diphosphate kinase activity

Nucleoside diphosphate (NDP) kinase catalyzes the phosphorylation of ribo- and deoxyribonucleosides diphosphates into triphosphates. NDP kinase is also involved in malignant tumors and was shown to activate in vitro transcription of the c-myc oncogene by binding to its NHE sequence. The structure of the complex of NDP kinase with bound ADP shows that the nucleotide adopts a different conformation from that observed in other phosphokinases with an internal H bond between the 3'-OH and the beta-O made free by the phosphate transfer. We use intrinsic protein fluorescence to investigate the inhibitory and binding potential of nucleotide analogues phosphorylated in 3'-OH position of the ribose to both wild type and F64W mutant NDP kinase from Dictyostelium discoideum. Due to their 3'-phosphate, 5'-phosphoadenosine 3'-phosphate (PAP) and adenosine 3'-phosphate 5'-phosphosulfate (PAPS) can be regarded as structural analogues of enzyme-bound ADP. The KD of PAPS (10 microM) is three times lower than the KD of ADP. PAPS also acts as a competitive inhibitor toward natural substrates during catalysis, with a KI in agreement with binding data. The crystal structure of the binary complex between Dictyostelium NDP kinase and PAPS was solved at 2.8-A resolution. It shows a new mode of nucleotide binding at the active site with the 3'-phosphate of PAPS located near the catalytic histidine, at the same position as the gamma-phosphate in the transition state. The sulfate group is directed toward the protein surface. PAPS will be useful for the design of high affinity drugs targeted to NDP kinases.

Pre-steady state of reaction of nucleoside diphosphate kinase with anti-HIV nucleotides

The pre-steady-state reaction of Dictyostelium nucleoside diphosphate (NDP) kinase with dideoxynucleotide triphosphates (ddNTP) and AZT triphosphate was studied by quenching of protein fluorescence after manual mixing or by stopped flow. The fluorescence signal, which is correlated with the phosphorylation state of the catalytic histidine in the enzyme active site, decreases upon ddNTP addition according to a monoexponential time course. The pseudo-first order rate constant was determined for different concentrations of the various ddNTPs and was found to be saturable. The data are compatible with a two-step reaction scheme, where fast association of the enzyme with the dideoxynucleotide is followed by a rate-limiting phosphorylation step. The rate constants and dissociation equilibrium constants determined for each dideoxynucleotide were correlated with the steady-state kinetic parameters measured in the enzymatic assay in the presence of the two substrates. It is shown that ddNTPs and AZT triphosphate are poor substrates for NDP kinase with a rate of phosphate transfer of 0.02 to 3.5 s-1 and a KS of 1-5 mM. The equilibrium dissociation constants for ADP, GDP, ddADP, and ddGDP were also determined by fluorescence titration of a mutant F64W NDP kinase, where the introduction of a tryptophan at the nucleotide binding site provides a direct spectroscopic probe. The lack of the 3'-OH in ddNTP causes a 10-fold increase in KD. Contrary to "natural" NTPs, NDP kinase discriminates between various ddNTPs, with ddGTP the more efficient and ddCTP the least efficient substrate within a range of 100 in kcat values.

Investigating the dielectric effects of channel pore water on the electrostatic barriers of the permeation ion by the finite difference Poisson-Boltzmann method

In this paper, the finite difference Poisson-Boltzmann (FDPB) method with four dielectric constants is developed to study the effect of dielectric saturation on the electrostatic barriers of the permeation ion. In this method, the inner shape of the channel pore is explicitly represented, and the fact that the dielectric constant inside the channel pore is different from that of bulk water is taken into account. A model channel system which is a righthanded twist bundle with four alpha-helical segments is provided for this study. From the FDPB calculations, it is found that the difference of the ionic electrostatic solvation energy for wider domains depends strongly on the pore radius in the vicinity of the ion when the pore dielectric constant is changed from 78 to 5. However, the electrostatic solvation energy of the permeation ion can not be significantly affected by the dielectric constant in regions with small pore radii. Our results indicate that the local electrostatic interactions inside the ion channel are of major importance for ion electrostatic solvation energies, and the effect of dielectric saturation on the electrostatic barriers is coupled to the interior channel dimensions.

AlF3 mimics the transition state of protein phosphorylation in the crystal structure of nucleoside diphosphate kinase and MgADP

Nucleoside diphosphate kinase reversibly transfers the gamma-phosphate of ATP onto its active site histidine. We have investigated the transition state of histidine phosphorylation with the high-resolution crystal structures of the enzyme from Dictyostelium discoideum with MgADP and either aluminium or beryllium fluoride. The bound aluminium fluoride species is the neutral species AlF3 and not the more common AlF4-. AlF3 forms a trigonal bipyramid that makes it an accurate analog of the transition state of the gamma-phosphate of ATP undergoing transfer to the catalytic histidine. Its axial ligands are a histidine nitrogen and a beta-phosphate oxygen. Beryllium fluoride also binds at the same position and with the same ligands but in a tetrahedral geometry resembling the Michaelis complex rather than the transition state. The two x-ray structures show explicit enzyme-substrate interactions that discriminate between the ground and the transition states of the reaction. They also illustrate the partially dissociative geometry of the transition state of phosphoryl transfer and demonstrate the potential applications of metallofluorides for the study of kinase mechanisms.

Experimental study on microvascular anastomosis using a dissolvable stent support in the lumen

A new method for microvascular anastomosis was developed and compared with conventional techniques, using the rabbit femoral artery. A dissolvable stent biomaterial was placed in the lumen to expose the vessel walls clearly, so that the quality of anastomosis could be improved. The results showed no significant difference in immediate and late patency rates between the methods, but the use of the stent resulted in faster repair, less dilation at the anastomosis, and less narrowing of the distal segments, causing apparently minor hemodynamic disturbance, with increased blood flow distally. Minor damage to the vessel walls and rapid healing of the wound were verified by histologic evaluation.

Laser-induced multiphoton fluorescence of hemoglobin

Hemoglobin (Hb) and other samples were irradiated by the 1064 nm nanosecond pulses of an Nd:YAG laser. At room temperature, we observed two red fluorescence bands, which resulted from the absorption of two 1064 nm photons in Hb, and measured the fluorescence emission spectra in the red spectral region for Hb and hematoporphyrin derivative. A red shift of the wavelength and a mirror image in the intensity of fluorescence emissions by two-photon excitation were observed. It is shown that the fluorescence of Hb originates from the heme group. In addition, we also observed fluorescence emission at 392 nm for Hb, which may be from its tryptophan groups.

Fluorescence of proteins induced by two-photon absorption

At room temperature, the UV fluorescence of trypsin, thyroglobulin, hemoglobin and albumin are observed; these molecules undergo two-photon absorption when they are excited with the radiation of a frequency-duplicated Q-switched Nd:YAG laser. It is shown that the fluorescence of these proteins comes from the tryptophan residues and that it has a red shift of about 20 nm relative to the one-photon fluorescence. We suggest that the weak emission from tyrosine arises from the forbidden two-photon transition. The influence of concentration on the fluorescence of hemoglobin and tryptophan is discussed. The two-photon absorption cross-sections are estimated.