Large trans-ethnic meta-analysis identifies AKR1C4 as a novel gene associated with age at menarche

STUDY QUESTION

Does the expansion of genome-wide association studies (GWAS) to a broader range of ancestries improve the ability to identify and generalise variants associated with age at menarche (AAM) in European populations to a wider range of world populations?

SUMMARY ANSWER

By including women with diverse and predominantly non-European ancestry in a large-scale meta-analysis of AAM with half of the women being of African ancestry, we identified a new locus associated with AAM in African-ancestry participants, and generalised loci from GWAS of European ancestry individuals.

WHAT IS KNOWN ALREADY

AAM is a highly polygenic puberty trait associated with various diseases later in life. Both AAM and diseases associated with puberty timing vary by race or ethnicity. The majority of GWAS of AAM have been performed in European ancestry women.

STUDY DESIGN, SIZE, DURATION

We analysed a total of 38 546 women who did not have predominantly European ancestry backgrounds: 25 149 women from seven studies from the ReproGen Consortium and 13 397 women from the UK Biobank. In addition, we used an independent sample of 5148 African-ancestry women from the Southern Community Cohort Study (SCCS) for replication.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Each AAM GWAS was performed by study and ancestry or ethnic group using linear regression models adjusted for birth year and study-specific covariates. ReproGen and UK Biobank results were meta-analysed using an inverse variance-weighted average method. A trans-ethnic meta-analysis was also carried out to assess heterogeneity due to different ancestry.

MAIN RESULTS AND THE ROLE OF CHANCE

We observed consistent direction and effect sizes between our meta-analysis and the largest GWAS conducted in European or Asian ancestry women. We validated four AAM loci (1p31, 6q16, 6q22 and 9q31) with common genetic variants at P < 5 × 10-7. We detected one new association (10p15) at P < 5 × 10-8 with a low-frequency genetic variant lying in AKR1C4, which was replicated in an independent sample. This gene belongs to a family of enzymes that regulate the metabolism of steroid hormones and have been implicated in the pathophysiology of uterine diseases. The genetic variant in the new locus is more frequent in African-ancestry participants, and has a very low frequency in Asian or European-ancestry individuals.

LARGE SCALE DATA

N/A.

LIMITATIONS, REASONS FOR CAUTION

Extreme AAM (<9 years or >18 years) were excluded from analysis. Women may not fully recall their AAM as most of the studies were conducted many years later. Further studies in women with diverse and predominantly non-European ancestry are needed to confirm and extend these findings, but the availability of such replication samples is limited.

WIDER IMPLICATIONS OF THE FINDINGS

Expanding association studies to a broader range of ancestries or ethnicities may improve the identification of new genetic variants associated with complex diseases or traits and the generalisation of variants from European-ancestry studies to a wider range of world populations.

STUDY FUNDING/COMPETING INTEREST(S)

Funding was provided by CHARGE Consortium grant R01HL105756-07: Gene Discovery For CVD and Aging Phenotypes and by the NIH grant U24AG051129 awarded by the National Institute on Aging (NIA). The authors have no conflict of interest to declare.

[Analysis on prediction power of HIV infection risk assessment tool in men who have sex with men in Guizhou province]

Objective: To evaluate the prediction power of HIV infection risk assessment tool and the applicability in MSM in Guizhou province. Methods: MSM were recruited through snowball sampling method. Questionnaire surveys were conducted among the MSM using HIV infection risk assessment tool, and combined with HIV serologic test results, the risk prediction power of HIV infection risk assessment tool was evaluated. Results: A total of 3 379 MSM were recruited from January 2018 to December 2019 in Guizhou. The HIV infection rate was 3.3%(111/3 379). The mean risk scores of HIV positive and HIV negative MSM were (12.15±3.08) and (12.07±3.07), respectively. The difference in risk score was significant between MSM with different HIV status (t=8.69, P<0.001). According to the principle of decision tree, individual risk scores were divided into following three categories: ≤11.96, 11.97-14.80 and >14.80, the HIV infection rate was 0.8%, 4.3% and 8.6% respectively, suggesting that the higher the individual risk score was, the higher the HIV infection rate was (trend χ²=88.18, P<0.001). Multivariate logistic regression analysis showed that the higher the individual risk score was, the higher the risk of HIV infection was. Compared to the total score ≤11.96, the aOR values at total scores of 11.97-14.80 and >14.80 were 6.34 (95%CI: 3.38-11.88) and 14.07(95%CI: 7.44-26.61), respectively. The risk of HIV infection in Miao ethnic group was higher than that in Han ethnic group (aOR=1.83, 95%CI:1.04-3.21), and the risk of HIV infection in those with education level of primary school and below was higher than that in undergraduates or those with education level of junior college and above (aOR=2.50, 95%CI:1.06-5.88), and the risk of HIV infection was higher in those who had bisexual behaviors than in those who had homosexual behaviors (aOR=1.95, 95%CI:1.19-3.19). The risk of HIV infection was higher in those who had never received HIV testing (aOR=1.53, 95%CI:1.01-2.33). The area under the receiver operating characteristic (ROC) curve and area under ROC (AUC) for HIV infection prediction was 0.751 (95%CI:0.710-0.792, P<0.001). The maximum Youden's index was individual risk score of 12.56, and the sensitivity of the risk assessment tool was 0.838, and its specificity was 0.412. Conclusions: The results of HIV infection risk assessment tool in Guizhou indicated that in MSM the higher the individual risk score, the higher the risk of HIV infection is. The tool can be used to evaluate the risk of HIV infection in MSM, but the specificity should be improved.

Down-regulation of long non-coding RNA DUXAP8 suppresses proliferation, metastasis and EMT by modulating miR-498 through TRIM44-mediated AKT/mTOR pathway in non-small-cell lung cancer

OBJECTIVE

The long non-coding RNA double homeobox A pseudogene 8 (DUXAP8) was reported to be involved in the initiation and development of multiple cancers. However, the detailed biological role of DUXAP8 in non-small-cell lung cancer (NSCLC) remains unclear. Herein, we aimed to explore the biological function and molecular mechanism of DUXAP8 in NSCLC.

PATIENTS AND METHODS

The levels of DUXAP8, microRNA-498 (miR-498) and tripartite motif-44 (TRIM44) were detected by Quantitative Real-time polymerase chain reaction (qRT-PCR). The cell proliferation, migration and invasion were detected by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and transwell assays. Protein expression levels were detected by Western blot. The target relationships among DUXAP8, miR-498 and TRIM44 were predicted by starBase2.0 and confirmed using luciferase reporter and RNA pull-down assays. To detect the role of DUXAP8 in vivo, tumor xenografts were created.

RESULTS

DUXAP8 and TRIM44 were upregulated in NSCLC tissues and cell lines, while miR-498 was downregulated. Functionally, knockdown of DUXAP8 could repress proliferation, migration, invasion, Epithelial-Mesenchymal Transition (EMT) and phosphorylation of AKT/mTOR in NSCLC cells. This inhibition could be restored by inhibiting miR-498 or overexpressing TRIM44. Furthermore, we also observed a positive correlation between DUXAP8 and TRIM44 expression, while the expressions of miR-498 and DUXAP8, as well as miR-498 and TRIM44, were negatively correlated in NSCLC tissues. Importantly, DUXAP8 could regulate the expression of TRIM44 via miR-498. Moreover, knockdown of DUXAP8 notably decreased the xenograft tumor volume, weight and number of metastatic nodules in vivo.

CONCLUSIONS

Our results identified that LncRNA DUXAP8 could regulate cell proliferation, metastasis and EMT in NSCLC cells by inhibiting miR-498 through the activation of TRIM44-mediated AKT/mTOR pathway.

[Risk factors of permanent stoma in rectal cancer patients undergoing transabdominal anterior resection with temporary stoma]

Objective: To investigate the risk factors of turning temporary stoma into permanent stoma in rectal cancer patients undergoing transabdominal anterior resection with temporary stoma. Methods: A case-control study was carried out. Data of rectal cancer patients who underwent transabdominal anterior resection with temporary stoma and completed follow-up in Department of General Surgery of Xiangya Hospital of Central South University from June 2008 to June 2018 were collected and analyzed. In this study, temporary stoma included defunctioning stoma (ostomy was made during operation) and salvage stoma (ostomy was made within one month after operation due to anastomotic leakage or severe complications). Cases of multiple intestinal tumors were excluded. A total of 308 rectal cancer patients were enrolled in the study, including 198 males and 110 females with a median age of 56 (48-65) years. Ninety-four patients received intraperitoneal chemotherapy during operation. Among 308 patients, upper rectal cancer was observed in 64 cases, middle rectal cancer in 89 cases and low rectal cancer in 155 cases. Twenty patients underwent transverse colostomy and 288 underwent ileostomy. Phone call following-up was conducted from August to September 2019 to investigate whether stoma was reversed, causes of reversal failure, and tumor relapsed or not in detail. Permanent stoma was defined as that the stoma was still not reversed by the latest follow-up. The univariate analysis was performed with chi-square test or Fisher's exact test, and variables with P value < 0.10 were included in the non-conditional logistic regression model for multivariate analysis. Results: The median follow-up time was 54.3 (32.4-73.8) months. During follow-up, 8 cases had local recurrence and 37 cases had distant metastasis. Among the 308 patients with temporary ostomy, 247 (80.2%) patients had stomas reversed and the median interval time was 4.5 (3.5-6.1) months. The median interval time in 65 patients with salvage stoma was significantly longer that in 182 patients with defunctioning stoma [5.5 (4.3-7.5) vs. 4.2 (3.4-5.5) months; Z=-4.387, P<0.001]. The temporary ostomy was confirmed to become permanent stoma in 61 patients (19.8%), including 45 cases of defunctioning stoma and 16 cases of salvage stoma. Univariate analysis showed that preoperative anemia, intraperitoneal chemotherapy during operation, middle rectal cancer, transverse colostomy, pathological stage, postoperative local recurrence and distant metastasis were associated with permanent stoma (all P<0.10). Multivariate analysis revealed that the intraperitoneal chemotherapy during operation (OR=1.961, 95% CI: 1.029-3.738, P=0.041), middle rectal cancer (OR=2.401, 95% CI: 1.195-4.826, P=0.014), transverse colostomy (OR=3.433, 95% CI: 1.234-9.553, P=0.018), and distant metastasis (OR=8.282, 95% CI:3.820-17.954, P<0.001) were independent risk factors of permanent stoma. Conclusions: There is high risk of turning temporary stoma into permanent stoma among rectal cancer patients undergoing transabdominal anterior resection who receive intraperitoneal chemotherapy during operation, present as the middle rectal cancer, undergo transverse colostomy or develop distant metastasis. Surgeons need to evaluate and balance the risks and benefits thoroughly, and then inform the patients in order to avoid potential conflicts.

[Association between family history of diabetes and incident diabetes of adults: a prospective study]

Objective: To evaluate the association betweew family history of diabetes and incident diabetes of adults. Methods: A total of 49 266 participants in the China Kadoorie Biobank (CKB) study from Wuzhong district of Suzhou city were included in the analysis, after the exclusion of those with heart disease, stroke, cancer and diabetes at baseline survey. The person-year of follow-up was calculated from the date on completion of baseline survey to the date on any firstly-occurred event, i.e., diabetes incidence, death, loss of follow-up, or December 31, 2013. Cox regression model was used to estimate the hazards ratios of the association between family history of diabetes and incident diabetes. Results: During 348 677 person-years of the follow-up (median 7.08 years), a total of 423 men and 791 women were diagnosed as having diabetes. Compared to those without diabetic family history, participants with family history of diabetes showed a higher risk of diabetes, with a HR (95%CI) of 1.90 (1.57-2.29), and the risk increased with the number of relatives suffering from diabetes (Pfor trend<0.05). The family history of maternal type, sibling type, and sibling and parental type had a statistically significant association with the risk of diabetes. The adjusted HR (95%CI) was 2.03 (1.45-2.77), 2.07 (1.56-2.68) and 2.39 (1.14-4.34), respectively. Modification effects of tobacco smoking, alcohol drinking, body mass index and physical activity on the association between diabetic family history and risk of diabetes were not observed in the study (Pfor interaction >0.05). Conclusions: Diabetic family history is associated with the increased incident diabetes, and the risk increased with the number of relatives suffering from diabetes.

[A study on the relationship between insufficient sleep and obesity among children and adolescents in China]

Objective: To analyze the relationship between insufficient sleep and obesity or central obesity in Chinese Han children and adolescents aged 9-18 years. Methods: A total of 172 710 students who participated in the 2014 Chinese National Survey on Students Constitution and Health with complete data of sleep duration and physical examination, were selected as study subjects. Insufficient sleep was defined, according to the amount of sleep for pediatric populations recommended by the American Academy of Sleep Medicine. Obesity and central obesity of children and adolescents were judged by experts from the Group of China Obesity Task Force and Health Industry Standards in China. Differences between groups were compared by using the t test or χ(2) test. Logistic regression method was applied to assess the relationship between insufficient sleep and obesity or central obesity. Results: In 2014, numbers of students with insufficient sleep, obesity and central obesity among Chinese Han children and adolescents aged 9-18 years appeared as 133 410 (77.2%), 11 145 (6.5%), and 12 603 (17.8%), respectively. Among the students with insufficient sleep, 8 358 (6.3%) were with obesity and 12 244 (17.9%) were with central obesity. The prevalence of obesity and central obesity among boys with insufficient sleep was higher than that in girls. Pupils with insufficient sleep showed the highest prevalence of obesity and central obesity. After controlling for potential confounders, the risk of obesity appeared an increase of 14.5% (OR=1.145, 95%CI: 1.092-1.200) and the risk of central obesity increased by 12.7% (OR=1.127, 95%CI: 1.078-1.178) in students with insufficient sleep, when compared with those with adequate sleep. Compared with those whose daily sleep duration was less than 6 hours, the ones who slept 7-10 hours per day showed significantly reduction on the risk of obesity and central obesity in students. Conclusions: Insufficient sleep significantly increase the risk of obesity and central obesity in children and adolescents while adequate sleep of 7-10 hours per day would reduce the risk of obesity and central obesity in students.

[Clinical application effects of portable visual retractor in superficial temporal fascia flap harvesting]

Objective: To explore the clinical application effects of portable visual retractor in superficial temporal fascia flap harvesting. Methods: From January 2010 to June 2019, 27 patients meeting the inclusion criteria and planning to perform operation of superficial temporal fascia flap harvesting were admitted to the Department of Plastic and Reconstructive Surgery of the First Clinical Medical Center of the People's Liberation Army General Hospital. The patients were divided into traditional surgical method group [6 males and 3 females, aged (34±14) years], cold light source retractor group [6 males and 4 females, aged (35±16) years], and portable visual retractor group [7 males and 1 female, aged (30±14) years] according to way of superficial temporal fascia flap harvesting. The superficial temporal fascia flaps of patients in traditional surgical method group were resected by traditional way of resection, and the superficial temporal fascia flaps of patients in cold light source retractor group and portable visual retractor group were resected at assistance of cold light source retractor and portable visual retractor, respectively. Length of incision, operation time, intraoperative blood loss volume, postoperative drainage volume, and postoperative complication of patients in 3 groups were observed and recorded. Data were processed with Fisher's exact probability test, one-way analysis of variance, least significant difference test, Kruskal-Wallis H test, and Bonferroni correction. Results: The length of incision of patients in visual retractor group was (3.6±0.8) cm, significantly shorter than (12.6±1.6) cm in traditional surgical method group and (5.8±0.9) cm in cold light source retractor group (P<0.05). The incision length of patients in traditional surgical method group was significantly longer than that in cold light source retractor group (P<0.05). The operation time of patients in visual retractor group was 24.0 (23.3, 25.8) min, significantly shorter than 35.0 (30.5, 36.5) min in traditional surgical method group and 28.5 (26.8, 30.5) min in cold light source retractor group (H=16.5, 9.8, P<0.05). The operation time of patients in traditional surgical method group was significantly longer than that in cold light source retractor group (H=6.6, P<0.05). The intraoperative blood loss volume was (26±3) mL of patients in visual retractor group, significantly less than (34±4) mL in traditional surgical method group and (30±6) mL in cold light source retractor group (P<0.05). The intraoperative blood loss volume of patients in traditional surgical method group was significantly more than that in cold light source retractor group (P<0.05). The postoperative drainage volumes of patients in visual retractor group, cold light source retractor group, and traditional surgical method group were (33±4), (34±6), and (31±7) mL, respectively, and there were no significantly statistical differences in postoperative drainage volumes among patients in the three groups (F=0.3, P>0.05). There were no severe complications such as ischemia and necrosis of superficial temporal fascia flaps in patients of the three groups. One patient in cold light source retractor group had subcutaneous hematoma after operation, which was improved by removing stitches and hematoma. Conclusions: Superficial temporal fascia flap harvesting at the assistance of portable visual retractor has the advantages of clear visual field, simple operation, short operation time, small incision, and less intraoperative blood loss.

[Monomorphic epitheliotropic intestinal T-cell lymphoma: a clinicopathological analysis of twelve cases]

Objective: To investigate the clinicopathological features, diagnosis and differential diagnosis of monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL). Methods: A total of 12 specimens were collected, which were surgically resected and verified as MEITL by postoperative pathology, immumohistochemical staining and gene rearrangement at the First Affiliated Hospital of Nanjing Medical University from 2012 to 2018, and all of these had complete clinical and pathological data. The MEITL cases were reviewed to compare the clinicopathological characteristics, including morphologic and immunophenotypic features and followed up by telephone and clinic visit. Results: All the cases were diagnosed with MEITL. There were 8 males and 4 females. Male to female ratio was 2∶1, at a median age of 54 years. The sites of involvement included jejunum (4 cases), ileum (5 cases), duodenum (1 case), ileocecal junction (1 case) and rectum (1 case). The neoplastic cells were monotonous of small to intermediate cells in size with round to slightly irregular nuclei in 11 cases. The immunophenotyping showed that CD3 (12/12), CD8 (11/12), CD43 (11/12), CD56 (11/12), TIA-1 (12/12) were positive; CD5 (12/12), Gran B (9/12), and perforin (7/12) were negative. Two cases aberrantly expressed the B-cell marker CD20. A high proliferation index was demonstrated by Ki-67 immunostaining. In situ hybridization for EBER was all negative(12/12). The whole exome sequencing(WES) mutational landscape of MEITL was remarkably homogeneous, showing significantly enriched clusters among histone modifier genes, JAK-STAT and MAPK-signal pathways. Histonelysine N-methytransferase SETD2 gene was mutated in 2/4 tumors. All the patients analyzed harbored at least one mutation in the JAK-STAT signal pathway, including STAT5B (2/4), JAK3 (3/4) and STAT5A (2/4). Furthermore, frequent alterations (TP53) were observed in the MAPK pathway in 3/4 of MEITL cases. The CNV analysis derived from WES data identified multiple regions of frequent gains and losses. In particular, gains in 1q, 7q and 9q, and recurrent losses involving 7p and 8p were observed. Conclusions: MEITL is a rare and aggressive type of extranodal T-cell lymphoma. The differential diagnosis of MEITL includes EATL, extranodal NT/T-cell lymphoma and other types of PTCL. Diagnosis should be correlated to clinical symptoms while the final diagnosis is mainly based on the pathological features, immunophenotypes and genetic testing.

[Interpretation of clinical practice guideline for anorectal day surgery 2019 edition]

As the rapid development of minimally invasive techniques, anesthesia, and enhanced recovery after surgery (ERAS), anorectal day surgery receiving more and more attention by improving efficiency of medical care while reducing cost and hospitalized infection. However, day surgery also faces the challenge of completing the whole process from patient admission to discharge within 24 hours. Therefore, establishing a reasonable and detailed day surgery process is the cornerstone to guarantee safe medical practice and patients satisfaction. National Clinical Research Center for Geriatric Disorders (Xiangya), together with China Ambulatory Surgery Alliance formulates the clinical practice guideline for anorectal day surgery 2019 edition. Here we make some interpretations of the guidelines on the detailed process of anorectal day surgery, including indication, preoperative examination, preoperative risk evaluation, health education, assessment of day surgery anesthesia and before leaving postanesthesia care unit (PACU), postoperative management, assessment of discharge and follow-up, for the convenience of various medical centers.

Works on heart, how about brain? Effect of hyperkalemia on focal cerebral ischemia/reperfusion injury in rats

OBJECTIVE

To investigate the effects of hyperkalemia on the brain after I/R in h transient middle cerebral artery occlusion (tMCAO) model.

MATERIALS AND METHODS

A total of 120 adult male SD rats were randomly assigned to four groups: (1) hyperkalemia 80 µg/g (HK80) group; (2) hyperkalemia 40 µg/g (HK40) group; (3) normal saline (NS) group; (4) sham (SH) group. The concentration of serum K+ was elevated in HK80 and HK40 groups. The transient middle cerebral artery occlusion (tMCAO) model was used to assess the effect of hyperkalemia on the brain after I/R. After 24 h reperfusion, the infarct volume and cell damage of rat's I/R brain tissue sections were analyzed. The concentration of K+, Ca2+ and calmodulin (CaM), the activity of Ca-ATPase, the expression of Western blot of Ca2+/calmodulin-dependent protein kinase II (CaMKII) and Na+/Ca2+ exchanger 1 (NCX1), were also measured.

RESULTS

After 24 h reperfusion, compared with NS group, the two-hyperkalemia groups (HK80 and HK40) were with less infarct volume and cell damage, higher concentration of K+ but lower Ca2+ and CaM compared with NS group. The activity of Ca-ATPase was also elevated, the expression of CaMK II and NCX1 were down-regulated in the two hyperkalemia groups.

CONCLUSIONS

Hyperkalemia could also ameliorate the brain I/R injury by alleviating calcium overload inhibiting the activity of NCX1, lowering the concentration of Ca2+.

[Relationship between gH genotyping and clinical characteristics of children with congenital cytomegalovirus infection]

Objective: To study the relationship between human cytomegalovirus (HCMV) envelope glycoprotein gene H and clinical features of children with congenital cytomegalovirus infection. Methods: A cohort study was conducted. Newborns diagnosed with congenital cytomegalovirus infection, hospitalized in the Department of Neonatology and Neonatal Intensive Care Unit (NICU) of the Children's Hospital, Zhejiang University School of Medicine, were included from July 2013 to December 2015.HCMV-DNA gH typing in urine, sputum or blood was conducted. Patients then were divided into gH1 group and gH2 group according to gH genotypes. Patients' data during hospitalization in newborn and 3-5 years of follow-up were collected.The relationships between gH genotype and clinical manifestations, laboratory examinations, hearing loss and neurological prognosis were analyzed by chi-square test, t test and non-parametric test. Results: A total of 21 cases were enrolled as congenital HCMV infection and followed-up for 3-5 years. Among them, 14 (67%) were gH1 type and 7 (33%) were gH2 type. No mixed infection was found. In the two groups, there were no significant differences in the ratio of males (9/14 vs. 3/7,P=0.397), or birth weight ((2 609±686) vs. (3 021±451) g, t=-1.436, P=0.167). Gestational age of gH1 group was younger than that of gH2 group (38 (29-40) vs. 39(38-40) weeks, Z=-2.18, P=0.029). Moderate to severe hearing loss detected by neonatal auditory brainstem response were found in 40 ears (20 cases). It was higher in gH1 group than that in gH2 group (4/22 vs.0/18, χ(2)=5.145, P=0.023). In the imaging examination of the nervous system, the Alarcon score of gH1 group was lower than that of gH2 group (0.4±0.3 vs. 1.3±1.1, t=-2.459,P=0.024).No significant statistical difference was found in the probability of motor or language development lag in gH2 group and gH1 group (4/7 vs.4/14, P=0.346). Conclusions: Compared with gH2 infection, gH1 infection in children has a younger gestational age. The major type of hearing loss in neonatal period is gH1 infection. Children with gH2 congenital infections are more likely to suffer from nervous systems damage.

3.7 kW monolithic narrow linewidth single mode fiber laser through simultaneously suppressing nonlinear effects and mode instability

In this paper, we report a 3.7 kW all fiber narrow linewidth single mode fiber laser. The full width at half-maximum is about 0.30 nm, and the beam quality is Mx2=1.358, My2=1.202 at maximum output power. The laser is achieved by simultaneously suppressing nonlinear effects and mode instability (MI). Different seeds are injected into the main amplifier to study stimulated Raman scattering (SRS) effect. The results show that the phase modulated single frequency seed is benefit to suppress the SRS effect. For the phase modulated single frequency seed, inserting a filter in preamplifier will suppress amplified spontaneous emission (ASE) and decrease the backward power. By optimizing the coiling of active fiber, the MI effect is suppressed.

[A multicenter, retrospective study of pathogenic bacteria distribution and drug resistance in febrile neutropenic patients with hematological diseases in Shanghai]

目的

了解上海地区中性粒细胞缺乏（粒缺）伴发热血液病患者致病细菌的分布及耐药情况。

方法

回顾性分析2012年1月至2014年12月上海市12家医院血液科粒缺伴发热住院患者的临床分离菌株，用纸片扩散法进行药敏试验，WHONET 5.6软件分析病原菌分布及药敏数据。

结果

从上海地区粒缺伴发热患者中共分离出1 260株细菌，其中革兰阳性菌420株（33.3%），革兰阴性菌840株（66.7%）。排在前七位的分别是肺炎克雷伯菌158株（12.5%）、嗜麦芽窄食单胞菌120株（9.5%）、大肠埃希菌115株（9.1%）、铜绿假单胞菌109株（8.7%）、鲍曼不动杆菌83株（6.6%）、金黄色葡萄球菌70株（5.6%）和屎肠球菌63株（5.0%）。呼吸道分泌物标本中，非发酵菌占56.2%（350/623）。其中嗜麦芽窄食单胞菌占15.3%（95/623）。血液标本中，肠杆菌科细菌占42.3%（104/246），凝固酶阴性葡萄球菌占34.6%（85/246）。脓液标本中肠杆菌科细菌占39.4%（76/193），肠球菌属细菌占28.5%（55/193）。耐甲氧西林金黄色葡萄球菌葡萄球菌（MRSA）和耐甲氧西林凝固酶阴性葡萄球菌（MRCNS）的检出率分别为54.3%和82.5%，未发现耐利奈唑胺、万古霉素、替考拉宁葡萄球菌属菌株，耐万古霉素屎肠球菌的检出率为8.9%，肠球菌属未检出耐利奈唑胺的菌株。肠杆菌科细菌对碳青霉烯类药物高度敏感。铜绿假单胞菌对亚胺培南和美罗培南的耐药率已分别达34.1%和15.8%。嗜麦芽窄食单胞菌对米诺环素、左氧氟沙星、复方磺胺甲恶唑等药物敏感。鲍曼不动杆菌仅对头孢哌酮/舒巴坦的耐药率低于10.0%。肺炎克雷伯菌、嗜麦芽窄食单胞菌、铜绿假单胞菌、鲍曼不动杆菌等革兰阴性菌对大多常用抗菌药物的耐药率低于CHINET监测的数据。

结论

粒缺伴感染患者常见感染部位致病菌株分布有其特点，细菌耐药率整体低于CHINET全国医院大样本监测。

Bimorph material/structure designs for high sensitivity flexible surface acoustic wave temperature sensors

A fundamental challenge for surface acoustic wave (SAW) temperature sensors is the detection of small temperature changes on non-planar, often curved, surfaces. In this work, we present a new design methodology for SAW devices based on flexible substrate and bimorph material/structures, which can maximize the temperature coefficient of frequency (TCF). We performed finite element analysis simulations and obtained theoretical TCF values for SAW sensors made of ZnO thin films (~5 μm thick) coated aluminum (Al) foil and Al plate substrates with thicknesses varied from 1 to 1600 μm. Based on the simulation results, SAW devices with selected Al foil or plate thicknesses were fabricated. The experimentally measured TCF values were in excellent agreements with the simulation results. A normalized wavelength parameter (e.g., the ratio between wavelength and sample thickness, λ/h) was applied to successfully describe changes in the TCF values, and the TCF readings of the ZnO/Al SAW devices showed dramatic increases when the normalized wavelength λ/h was larger than 1. Using this design approach, we obtained the highest reported TCF value of −760 ppm/K for a SAW device made of ZnO thin film coated on Al foils (50 μm thick), thereby enabling low cost temperature sensor applications to be realized on flexible substrates.