[Impacts of glycemic variability on the relationship between time in range and estimated glycated hemoglobin in patients with type 1 diabetes mellitus].

Objective: This study is to investigate the relationship between time in range (TIR) and glucose management indicator (GMI), and the impact of glycemic variability (GV) on their relationship in patients with type 1 diabetes mellitus (T1DM). Methods: The CGM data were collected from a multicenter randomized clinical trial of adults (≥18 years old) with T1DM, including 83 T1DM patients, respectively from the Third Affiliated Hospital of Sun Yat-sen University (72 cases), Drum Tower Hospital Affiliated to Nanjing University School of Medicine (2 cases), and the First Affiliated Hospital of University of Science and Technology of China (9 cases). All subjects wore the iProTM2 system for 14 days at baseline (0-2 weeks), 3 months (12-14 weeks), and 6 months (24-26 weeks). Data derived from iProTM2 sensor was used to calculate CGM parameters. Correlation between TIR and GMI was explored according to different stratification of glycemic variability assessed by glucose coefficient of variation (CV). Predicted TIR in the fixed GMI value was calculated via the linear regression equations performed in the respective interquartile group of CV. Results: From November 2017 to June 2021, a total of 233 CGM data were collected with 83 collected from baseline, 80 from the 3-month follow-up, 70 from the 6-month follow-up. Patients including 27 males had a median (Q1, Q3) age of 30.69 (25.22, 38.43) years, with a diabetes duration of 10.05(4.46, 13.92) years. The median (Q1, Q3) and effective wearing time of available CGM data was 13.92 (13.02, 14.00) days and 91.61% (84.96%, 95.94%), and the value of TIR, GMI and CV was 60.34%±13.03%, 7.14%±0.61% and 41.01%±7.64%, respectively. There was a strong negative correlation between TIR and GMI (r=-0.822, P<0.001). Multiple linear regression analysis showed that the predictive value of TIR calculated from a given GMI was 8.352% higher when CV was up to standard (36%) than that when CV was down to standard. Based on the multiple linear regression equations generated from quartiles of CV, the predicted TIR value was decreased across the ascending quartiles with 69.98 % in the lowest quartile of CV (≤35.91%), 64.57 % in 25th-50th quartile of CV (35.91%75th quartile, CV>45.86%) when GMI was set as 7%. Conclusions: There is a strong correlation between TIR and GMI in adult patients with T1DM in patients with type 1 diabetes mellitus. CV influenced the relationship between TIR and GMI.

[Clinical characteristics of 21 infertile women with non-classic 21-hydroxylase deficiency].

Objective: To investigate the clinical features of infertile women with non-classic 21-hydroxylase deficiency (21-OHD). Methods: The study enrolled 21 infertile women with non-classic 21-OHD in Sun Yat-sen Memorial Hospital of Sun Yat-sen University from January 2009 to December 2018. The clinical presentation, endocrine hormone, glucolipid metabolism and treatment outcome were retrospectively analyzed. The diagnosis of non-classic 21-OHD was comprehensively based on clinical and hormonal characteristics. Results: Among 21 cases, the age was (29.9±2.9) years, the mean age at menarche was (13.6±2.0) years, body mass index was (22.1±2.9) kg/m2, and 38% (8/21) had oligomenorrhea. Hirsutism was diagnosed in 3 cases (14%, 3/21). Clitoromegaly was seen in 14% (3/21) and polycystic ovarian morphology was found in 33% (7/21) of the patients. The mean serum level of basal progesterone was (11.3±21.0) nmol/L, with 48% (10/21) having high basal progesterone level; after therapy by glucocorticoid, the level of progesterone was (1.9±2.0) nmol/L. Serum 17-hydroxyprogesterone concentration was (66.4±123.6) nmol/L; after therapy by glucocorticoid, it was (2.4±1.8) nmol/L. In the study increased testosterone, androstenedione and dehydroepiandrosterone sulfate were present in 62% (13/21), 52% (11/21) and 43% (9/21), respectively; and 52% (11/21) of patients manifested androgen excess and basal progesterone elevation; androgen levels decreased after therapy by glucocorticoid. The pregnancy rate was 76% (16/21). Out of 19 pregnancies, 6/19 ended in spontaneous miscarriages. Conclusions: Infertile women with non-classic 21-OHD are characterized by hyperandrogenism and basal progesterone elevation, whereas gonad axis disorder is not apparent. After no response to conventional therapy, adult infertile women with non-classic 21-OHD could achieve a desirable pregnancy outcome with proper treatment of glucocorticoid.

[Related factors for microalbuminuria in adult type 1 diabetes patients of short disease duration].

Objective: To investigate related factors for microalbuminuria in adult type 1 diabetes (T1D) patients of short disease duration (less than 5 years), and provide evidence for prevention of early diabetic kidney disease in this population. Methods: All adult patients enrolled in the Guangdong T1D translational medicine study between 2011 and 2017 with a disease duration of less than 5 years were included in this analysis. At enrollment, patients' demographic and clinical data were documented, and blood and urine samples were collected for the measurements of blood lipids, glycated hemoglobin A1c and urine albuminuria. Insulin resistance was evaluated by estimated glucose disposal rate (eGDR). Patients were categorized into groups based on urine albumin creatitine ratio (UACR): normoalbuminuric group (UACR<30 mg/g) and microalbuminuric group (UACR≥30 mg/g). Stepwise multivariate linear regression analysis was used to analyze risk factors for microalbuminuria in adult T1D patients of short disease duration. Results: A total of 384 patients were included in this analysis, and 51.3% (197/384) of which was female. The onset age of patients was (24.6±12.5) years, with a disease duration of 2.1(0.6, 3.5) years, body mass index of (19.8±3.2) kg/m(2), waist hip ratio of 0.85±0.21, and glycated hemoglobin A1c of (9.8±3.3)% at enrollment. Microalbuminuria occurred in 62 patients (16.1%). Multivariate linear analysis showed that higher glycated hemoglobin A1c, higher systolic blood pressure and more severe insulin resistance were related factors for microalbuminuria (t=2.322, 2.868 and -2.373, respectively, all P<0.05). Conclusions: Microalbuminuria was not rare in adult T1D patients of short disease duration. Inadequate glycemic control and insulin resistance were independent related factors for microalbuminuria in this population.

[The effect of mobile application based interactive peer support on glycemic control in patients with type 1 diabetes mellitus].

Objective: To evaluate the effect of mobile application (APP) based interactive peer support on glycemic control in patients with type 1 diabetes mellitus (T1DM). Methods: The data of the present study were from the largest mobile APP platform for patients with T1DM in China, Tangtangquan. Patients with T1DM who has registered in the APP for at least 1 year and had completed data entry were recruited. According to the monthly interaction index during the first year of APP registration (including four indicators: praise, comment, posting and collection), the eligible patients were divided into the high-interaction group and the low-interaction group. The changes from baseline of self-blood glucose monitoring frequency (SMBG), glycosylated hemoglobin (HbA1c), incidence of hyperglycemia and incidence of hypoglycemia were compared between the two groups after one year of using the APP. Results: A total of 238 patients with T1DM with an age of (27±8) years were included. Among them, 77.3% (184/238) were female. The baseline SMBG [the low-interaction group (1.71±1.14) times/day vs. the high-interaction group (1.82±1.15) times/day] and HbA1c [the low-interaction group (6.72±0.99)% vs. the high-interaction group (6.76±1.04)%] were comparable between the two groups. After one year use of the APP, the frequency of SMBG in the high-interaction group was significantly higher than that in the low-interaction group [ΔSMBG (0.59+2.06) times/d vs. (0.08+1.69) times/d, t=4.280, P=0.04), and the reduction of HbA1c was more obvious in the high-interaction group [ΔHbA1c (-0.40+1.10)% vs. (-0.06+1.13)%, t=5.651, P=0.018] than in the lower-interaction group. The incidence of hyperglycemia in the high-interaction group was significantly lower than that in the low-interaction group [13.19(6.22,23.19)% vs. 17.69(10.56,30.49)%, Z=2.850, P=0.005]. There was no significant difference in the incidence of hypoglycemia between the two groups [4.62(2.14, 8.03)% vs. 4.83(2.06, 8.87)%, Z=1.276, P=0.204]. The correlation analysis showed that interaction index was significantly associated with the reduction of HbA1c and incidence of hyperglycemia. Conclusion: Participation in interactive peer education via mobile APP may be beneficent for glycemic control in patients with T1DM.

[Awareness of preconceptional care and its related factors in women of child-bearing age with type 1 diabetes].

Objective: To investigate the awareness of preconception care among women of child-bearing age with type 1 diabetes (T1DM) and their self-management status, in order to provide evidence for establishment of management pathway for women with T1DM in pregnancy in China. Methods: This cross-sectional survey recruited female participants of child-bearing age from the cohort of Guangdong Type 1 Diabetes Translational Medicine Study conducted between June 2011 and December 2017. The participants were asked to fill out a questionnaire on the awareness of preconception care, their frequency of self-monitoring of blood glucose (SMBG) and other related variables. Chi-squared test or chi-squared test for trend was used in comparisons of categorical variables, and logistic regression analysis was performed to assess associated factors. Results: Totally, 441 women of child-bearing age with T1DM were investigated. The results show that their awareness of preconception care was poor (15.42%, 68/441). Higher educational level (χ(2trend)=3.990, P=0.046), experience of post-diabetes education evaluation (P<0.001), and better coverage of different modules in diabetes education (survival skills: χ(2)=7.525, P=0.004; basic knowledge: χ(2)=8.598, P=0.002; advanced knowledge: P<0.001) were associated with better awareness of preconception care. The average frequency of SMBG in these participants was 0.29 (0.14, 2.00) times per day, and only 8.5% (37/435) of them reached the frequency (≥4 times per day) recommended by guidelines. Moreover, 21.1% (92/435) of them hardly ever performed SMBG. Conclusion: Child-bearing age women with T1DM in Gunangdong had poor awareness of preconception care, with a much lower SMBG frequency than recommendation.

[Association of insulin resistance with dyslipidemia in adults with type 1 diabetes].

Objective: To investigate the relationship between insulin resistance (IR) and dyslipidemia in adults with type 1 diabetes (T1DM) and provide more insights on diabetes-related cardiovascular disease management. Methods: A cross-sectional study recruiting patients from Guangdong T1DM Translational Study cohort was conducted between 2011 and 2017. The patients aged ≥18 years, with a diabetes duration of ≥1 year were enrolled in the study. Plasma lipid profile data of eligible patients, including total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) were collected and their relationships with insulin resistance were analyzed. IR in these adults with T1DM was estimated by glucose disposal rate (eGDR) calculated by a model published previously. Patients with eGDR lower than 25 percentiles were grouped as severe IR, otherwise non-severe IR. Results: In total, 499 eligible patients were studied, among which 274 were women (54.9%). The level of eGDR was 8.43 (6.11, 10.63) mg kg(-1) min(-1) and the overall incidence of lipid disorders was 65.3% (326/499) in the study population. The result showed that eGDR was correlated with TC, TG, HDL-C and LDL-C (r=-0.163, -0.303, 0.170 and -0.150, respectively, all P<0.05). After adjusting for gender, age and diabetes duration, eGDR was still associated with TG, TC and LDL-C (all P<0.05). Stepwise multiple linear regression analysis showed that gender (female), elevated TC and declined HDL-C were independent factors associated with the severity of IR (t=5.651, 5.823 and 2.908, respectively, all P<0.05). Conclusions: IR is associated with dyslipidemiain in adults with T1DM. Elevated TC and decreased HDL-C are independent associated factors for insulin resistance.

[Clinical characteristics and classification diagnosis of newly diagnosed diabetes onset with ketosis or ketoacidosis in adult patients].

Objective: To describe the clinical characteristics and classification diagnosis of newly diagnosed diabetes onset with ketosis or ketoacidosis in adult patients. Methods: Medical records of newly diagnosed diabetes onset with ketosis or ketoacidosis in the Third Affiliated Hospital of Sun Yat-sen University between January 2011 and August 2016 were reviewed. Patients aged 18 years or older were included, while other diseases that may cause urinary ketoacidosis and special types of diabetes were excluded. Patients were classified as type 1 diabetes mellitus (T1DM) or type 2 diabetes mellitus (T2DM) or diabetes mellitus untyped based on discharged diagnosis, and groups were compared for differences in clinical profiles. Then the patient's medication, final diagnosis and outcome within 2 years of discharge were tracked through the inpatient and the outpatient medical record systems. Receiver operating characteristics (ROC) curves were analyzed to check the ability of clinical indicators such as onset age, body mass index (BMI) and C-peptide to discriminate T1DM from T2DM, and to find the best diagnostic cut-off points. Results: A total of 123 patients (88 males) were enrolled [with a mean age of (41.1±13.6) years old], with 37 patients (30.1%) diagnosed as T1DM, 60 patients (48.8%) diagnosed as T2DM and 26 patients (21.1%) diagnosed as Untyped. There was a statistically significant difference in onset age, BMI, blood pressure, blood gas pH and bicarbonate, blood lipids, fasting, 0.5 h and 2 h C-peptide level, any diabetic antibody and anti-glutamic acid decarboxylase antibody (GADA) positive rate, combined fatty liver ratio and family history among the three groups (all P<0.05). ROC curve analysis was performed on patients diagnosed with T1DM (n=36) and T2DM (n=87) after 2 years follow-up, and the area under the curve (AUC) of onset age, BMI, fasting C-peptide, 0.5 h and 2 h C-peptide was 0.735, 0.813, 0.855, 0.898, and 0.882, respectively. Conclusion: The ROC curve analysis indicates that C-peptide, onset age and BMI can provide effective diagnostic value, and the diagnostic value of C peptide is better than BMI and onset age.

[Glycemic control and its associated factors in children and adolescents with type 1 diabetes mellitus].

Objective: To explore the factors associated with glycemic control in children and adolescents with type 1 diabetes mellitus (T1DM) treated with continuous subcutaneous insulin infusion (CSII). Methods: Subjects were enrolled from the Guangdong Type 1 Diabetes Translational Medicine Study between June 2011 and August 2017. Patients with T1DM aged less than 18 years and treated with CSII for at least 6 months were included. Demographic data and clinical information on self-monitoring of blood glucose (SMBG), glycosylated hemoglobin (HbA1c) and insulin treatment were collected. Participants were categorized based on HbA1c levels as sufficient control group (HbA1c<7.5% ) and insufficient control group ( HbA1c≥7.5%). A multivariate logistic regression model was used to examine the factors associated with glycemic control. Results: A total of 142 participants (76 females, 66 males) with a median age of 13.0 (9.9, 15.0) years and a median disease duration of 3.0 (1.6, 5.0) years were enrolled. HbA1c was (8.2±2.0)% and 41.55%(59/142) of patients achieved the target for HbA1c. The frequency of SMBG was 5.0 (2.0, 8.0) and 3.0 (1.0, 4.0) tests per day (P<0.001), and the frequency of hypoglycemia was 2.0 (0.8, 4.0) and 1.0 (0, 2.0) times per week (P=0.003) in sufficient control group and insufficient control group, respectively. Sufficient glycemic control (HbA1c <7.5%) was associated with the frequency of SMBG (OR=1.238, 95% CI: 1.088-1.409, P=0.001). Conclusion: A higher frequency of SMBG is one of the key factors to achieve sufficient glycemic control among children and adolescents with T1DM treated with CSII.

Rs13405728 is associated with slow ovarian response in assisted reproductive technology.

OBJECTIVE: To explore the association between rs13405728 with slow ovarian response in assisted reproductive technology (ART). PATIENTS AND METHODS: 236 women, aged 21 to 35 years, were enrolled and grouped according to their genotypes, The polymorphism of rs13405728 was genotyped by DNA sequencing. RESULTS: There was no evidence of any difference in anti-Müllerian hormone (AMH), antral follicle count (AFC) among the three genotypes (p>0.05). The occurrence of slow response in genotype GG was lower than those in the other two genotypes (p<0.05). There were independent correlations between slow ovarian response with the dose of luteinizing hormone (LH) required and the genotypes of rs13405728 (p<0.05). CONCLUSIONS: There were significant independent correlations between slow ovarian response with the dose of LH required and the genotypes of rs13405728. Different mechanisms may be involved in poor response and slow response.

[Value of anti-Müllerian hormone in predicting pregnant outcomes of polycystic ovary syndrome patients undergone assisted reproductive technology].

Objective: Explore the value of anti-Müllerian hormone (AMH) in predicting pregnant outcomes of polycystic ovary syndrome (PCOS) patients undergone assisted reproductive technology. Methods: The study totally recruited 1 697 patients who underwent the first in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) cycle in Sun Yat-sen Memorial Hospital from the January 2014 to December 2015. The patients were divided into two groups based on the age<35 (n=758) and ≥35 years old (n=939) , compare the basic data and pregnant outcomes of controlled ovarian hyerstimulation. Spearman correlation method was conducted to analyze the relations between AMH and clinical outcomes. The logistic regression method and partial correlation analysis were used to judge the main factors which determine pregnancy outcomes by controlled the confounding factors. The receiver operating characteristic curve (ROC) was used to evaluate the predictive sensitivity and specificity of AMH. Results: In the group of PCOS patient younger than 35 years, AMH were correlated with the number of antral follicles (r=0.388) and retrieved oocytes (r=0.235) . When the effect of total dosage and starting dosage of gonadotropin were controlled, AMH was still significantly associated with the number of retrieved oocytes (P<0.05) . AMH had no predictive value for the clinical pregnancy of PCOS patient younger than 35 years (area under ROC curve=0.481, P=0.768) . In the group of PCOS patient≥35 years old, AMH were correlated with the number of antral follicles (r=0.450) , retrieved oocytes (r=0.399) , available embryo (r=0.336) and high quality embryo (r=0.235) . When the effect of total dosage and starting dosage of gonadotropin were controlled, the correlations were still significant between those indexes (all P<0.05) . AMH had no predictive value for the clinical pregnancy of PCOS patient ≥35 years old (area under ROC curve=0.535, P=0.560) . However, the clinical pregnancy rate of the group of PCOS patient ≥35 years old was slightly higher than the control group (P=0.062) . Conclusions: AMH has no predictive value for the pregnancy outcome of PCOS patient. The pregnancy rate of PCOS patient ≥35 years old is slightly higher than the younger group, because the PCOS patient may have better ovarian reserve.

[Insulin dose analysis during pregnancy in type 1 diabetic patients treated with insulin pump therapy].

Objective: To analyze the insulin dose of type 1 diabetic patients who treated with insulin pump therapy during pregnancy in order to explore the features of these patients' insulin requirement during gestation. Methods: A total of 12 well-controlled type 1 diabetic women patients who were treated with insulin pump therapy before and during gestation without any adverse pregnancy outcomes from June 2011 to December 2014 were selected from Guangdong Type 1 Diabetes Translational Medicine Study and included in the study. Demographic data, hemoglobin A1c (HbA1c) before pregnancy and before delivery, insulin dose, hypoglycemia episodes and pregnancy outcomes were collected to analyze the insulin dose of preconception, the 1(st,) the 2(nd) and the 3(rd) trimester to analyze the requirement of insulin before and throughout pregnancy. Results: Subjects were (26.9±2.6) years old, with a diabetes duration of (6.6±4.4) years. HbA1c were (5.8±0.5)% before conception. The preconception total daily insulin dose, basal rate, bolus and bolus proportion were (0.60±0.18)U/kg, (0.28±0.10)U/kg, (0.32±0.13)U/kg and (54.8±12.9)%, respectively. Both of the insulin dose indexes mentioned above changed significantly in different trimesters compared with that in preconception (P value was <0.001, 0.034, <0.001 and <0.001, respectively). The total daily insulin dose, bolus and bolus proportion kept increasing during pregnancy. In the 1(st,) the 2(nd) and the 3(rd) trimester, the total daily insulin dose rose by 0.2%, 45.4% and 72.7%, respectively, the bolus rose by 8.0%, 72.2% and 106.8%, respectively, and the bolus proportion rose by 8.0%, 16.8% and 19.0%, respectively. While the basal rate decreased by 9.0% in the 1(st) trimester and rose by 14.1% and 32.9% in the 2(nd) and 3(rd) trimester, respectively. Conclusions: In well-controlled pregnant women with type 1 diabetes mellitus, insulin requirement increased throughout pregnancy. Most of the increased insulin requirement was attributed to the bolus instead of the basal rate. When titrating the dose of insulin for the pregnant women complicated with type 1 diabetes mellitus, the physicians should consider their features of insulin requirement so as to optimize the glycemic control.

[Insulin regimes and impact on glycemic control in patients with type 1 diabetes].

Objective: To describe the insulin regimens and their associations with glycemic control and to explore factors associated with intensive insulin therapy. Methods: Patients with type 1 diabetes (T1DM) were recruited from Guangdong Type 1 Diabetes Mellitus Translational Medicine Study which was conducted in 16 centers in Guangdong province. The demographic and clinical data were collected. Patients were grouped according to different insulin regimens: insulin pump (R1), basal insulin plus regular insulin or short-acting insulin (R2), insulin injection 1-3 times per day (R3). Distribution of insulin regimens and the relationships between insulin regimens and hemoglobin A1c (HbA1c) were described. Multivariate logistic regression was used to identify factors associated with intensive insulin therapy. Results: A total of 1 421 patients with the age of 27.8 (19.4, 38.3) years and a duration of T1DM of 3.3 (0.5, 7.1) years were recruited. There was 12.3% of patients in R1 (n=175), 35.5% in R2 (n=504), and 52.2% in R3 (n=742), respectively. HbA1c was 8.0 (6.8, 9.3)%, 8.9 (7.1, 11.8)%, and 9.2 (7.5, 11.4)% in R1, R2, R3, respectively, and it was associated with insulin regimens (P<0.001). HbA1c target rate was 32.3%, 21.1%, 17.8% in R1, R2, R3, respectively (P=0.002). Older age (OR=1.01, P=0.027), higher education level (college or above) (OR=1.56, P=0.003), and higher household income (>30 000 yuan per year per person)(OR=1.45, P=0.009) were associated with intensive insulin therapy in adult patients. Conclusions: The study suggested that insulin therapy need to be optimized in patients with T1DM. The optimization of insulin regimens and diabetes education may be helpful for improvement of glycemic control.

Temperature-Dependent Asymmetry of Anisotropic Magnetoresistance in Silicon p-n Junctions.

We report a large but asymmetric magnetoresistance in silicon p-n junctions, which contrasts with the fact of magnetoresistance being symmetric in magnetic metals and semiconductors. With temperature decreasing from 293 K to 100 K, the magnetoresistance sharply increases from 50% to 150% under a magnetic field of 2 T. At the same time, an asymmetric magnetoresistance, which manifests itself as a magnetoresistance voltage offset with respect to the sign of magnetic field, occurs and linearly increases with magnetoresistance. More interestingly, in contrast with other materials, the lineshape of anisotropic magnetoresistance in silicon p-n junctions significantly depends on temperature. As temperature decreases from 293 K to 100 K, the width of peak shrinks from 90° to 70°. We ascribe these novel magnetoresistance to the asymmetric geometry of the space charge region in p-n junction induced by the magnetic field. In the vicinity of the space charge region the current paths are deflected, contributing the Hall field to the asymmetric magnetoresistance. Therefore, the observed temperature-dependent asymmetry of magnetoresistance is proved to be a direct consequence of the spatial configuration evolution of space charge region with temperature.

Crystal-momentum dispersion of ultrafast spin change in fcc Co.

Nearly twenty years ago, Beaurepaire and coworkers showed that when an ultrafast laser impinges on a ferromagnet, its spin moment undergoes a dramatic change, but how it works remains a mystery. While the current experiment is still unable to resolve the minute details of the spin change, crystal momentum-resolved techniques have long been used to analyze the charge dynamics in superconductors and strongly correlated materials. Here we extend it to probe spin moment change in the entire three-dimensional Brillouin zone for fcc Co. Our results indeed show a strong spin activity along the Δ line, supporting a prior experimental finding. The spin active pockets coalesce into a series of spin surfaces that follow the Fermi surfaces. We predict two largest spin change pockets which have been elusive to experiments: one pocket is slightly below the Δ line and the other is along the Λ line and close to the L point. Our theory presents an opportunity for the time-, spin- and momentum-resolve photoemission technique.

Theoretical Prediction of Carrier Mobility in Few-Layer BC2N.

An ideal semiconducting material should simultaneously hold a considerable direct band gap and a high carrier mobility. A 2D planar compound consisting of zigzag chains of C-C and B-N atoms, denoted as BC2N, would be a good candidate. It has a direct band gap of 2 eV, which can be further tuned by changing the layer number. At the same time, our first-principles calculations show that few-layer BC2N possesses a high carrier mobility. The carrier mobility of around one million sqaure centimeters per volt-second is obtained at its three-layer. As our study demonstrated, few-layer BC2N has potential applications in nanoelectronics and optoelectronics.

Serum visfatin is elevated in Chinese women with polycystic ovary syndrome, but might not be a reliable predictor of their glucose intolerance.

Both visfatin and polycystic ovary syndrome (PCOS) were previously reported to be in relation to abnormal glucose metabolism (AGM). The hypothesis was investigated in this paper that plasma visfatin level are elevated in Chinese women with PCOS, and could substitute oral glucose tolerance test (OGTT) as a simple predictor for their glucose intolerance. This cross-sectional study enrolled 119 women (91 newly diagnosed PCOS patients and 28 eumenorrheic age- and BMI- matched controls); anthropometric, hormonal, and metabolic parameters including serum visfatin were simultaneously measured in all participants. Plasma visfatin levels were compared between controls and PCOS subjects with various glucose metabolism status diagnosed by OGTT using 75 g of glucose. Pearson correlation coefficients were calculated to determine the correlations between various parameters. Receiver Operating Characteristic (ROC) analysis was performed to examine the diagnostic test performance of visfatin. Plasma visfatin levels were found to be significantly higher in our PCOS population compared to healthy controls (P less than 0.05). An increase in fasting visfatin concentrations with a worsening degree of glucose intolerance among PCOS patients was described. However, the difference did not reach statistical significance. In addition, visfatin was unexpectedly found to correlate with neither age, anthropometric, hormonal nor metabolic parameters. As a predictor for glucose intolerance to distinguish PCOS individuals with normal or abnormal glucose metabolism, visfatin was found to possess low potentially predictive ability according to ROC curve analysis. In conclusion, serum visfatin is significantly elevated in Chinese women with PCOS, but might not be a reliable predictor of their glucose intolerance.