Structural Lessons From the Mutant Proinsulin Syndrome

Insight into folding mechanisms of proinsulin has been provided by analysis of dominant diabetes-associated mutations in the human insulin gene (INS). Such mutations cause pancreatic β-cell dysfunction due to toxic misfolding of a mutant proinsulin and impairment in trans of wild-type insulin secretion. Anticipated by the "Akita" mouse (a classical model of monogenic diabetes mellitus; DM), this syndrome illustrates the paradigm endoreticulum (ER) stress leading to intracellular proteotoxicity. Diverse clinical mutations directly or indirectly perturb native disulfide pairing leading to protein misfolding and aberrant aggregation. Although most introduce or remove a cysteine (Cys; leading in either case to an unpaired thiol group), non-Cys-related mutations identify key determinants of folding efficiency. Studies of such mutations suggest that the hormone's evolution has been constrained not only by structure-function relationships, but also by the susceptibility of its single-chain precursor to impaired foldability. An intriguing hypothesis posits that INS overexpression in response to peripheral insulin resistance likewise leads to chronic ER stress and β-cell dysfunction in the natural history of non-syndromic Type 2 DM. Cryptic contributions of conserved residues to folding efficiency, as uncovered by rare genetic variants, define molecular links between biophysical principles and the emerging paradigm of Darwinian medicine: Biosynthesis of proinsulin at the edge of non-foldability provides a key determinant of "diabesity" as a pandemic disease of civilization.

Insertion of a synthetic switch into insulin provides metabolite-dependent regulation of hormone-receptor activation

Insulin-signaling requires conformational change: whereas the free hormone and its receptor each adopt autoinhibited conformations, their binding leads to structural reorganization. To test the functional coupling between insulin's "hinge opening" and receptor activation, we inserted an artificial ligand-dependent switch into the insulin molecule. Ligand-binding disrupts an internal tether designed to stabilize the hormone's native closed and inactive conformation, thereby enabling productive receptor engagement. This scheme exploited a diol sensor (meta-fluoro-phenylboronic acid at GlyA1) and internal diol (3,4-dihydroxybenzoate at LysB28). The sensor recognizes monosaccharides (fructose > glucose). Studies of insulin-signaling in human hepatoma-derived cells (HepG2) demonstrated fructose-dependent receptor autophosphorylation leading to appropriate downstream signaling events, including a specific kinase cascade and metabolic gene regulation (gluconeogenesis and lipogenesis). Addition of glucose (an isomeric ligand with negligible sensor affinity) did not activate the hormone. Similarly, metabolite-regulated signaling was not observed in control studies of 1) an unmodified insulin analog or 2) an analog containing a diol sensor without internal tethering. Although secondary structure (as probed by circular dichroism) was unaffected by ligand-binding, heteronuclear NMR studies revealed subtle local and nonlocal monosaccharide-dependent changes in structure. Insertion of a synthetic switch into insulin has thus demonstrated coupling between hinge-opening and allosteric holoreceptor signaling. In addition to this foundational finding, our results provide proof of principle for design of a mechanism-based metabolite-responsive insulin. In particular, replacement of the present fructose sensor by an analogous glucose sensor may enable translational development of a "smart" insulin analog to mitigate hypoglycemic risk in diabetes therapy.

[Consistency of peripheral whole blood and venous serum procalcitonin in children: a multicenter parallel controlled study]

Objective: To explore the consistency of peripheral whole blood and venous serum procalcitonin (PCT) levels, and the value of peripheral whole blood PCT in evaluating pediatric bacterial infection. Methods: This multicenter cross-sectional parallel control study was conducted in 11 children's hospital. All the 1 898 patients older than 28 days admitted to these hospitals from March 2018 to February 2019 had their peripheral whole blood and venous serum PCT detected simultaneously with unified equipment, reagent and method. According to the venous serum PCT level, the patients were stratified to subgroups. Analysis of variance and chi-square test were used to compare the demographic characteristics among groups. And the correlation between the peripheral blood and venous serum PCT level was investigated by quantitative Pearson correlation analysis.The PCT resultes were also converted into ranked data to further test the consistency between the two sampling methods by Spearman's rank correlation test. Furthermore, the ranked data were converted into binary data to evaluate the consistency and investigate the best cut-off of peripheral blood PCT level in predicting bacterial infection. Results: A total of 1 898 valid samples were included (1 098 males, 800 females),age 27.4(12.2,56.7) months. There was a good correlation between PCT values of peripheral whole blood and venous serum (r=0.97, P<0.01). The linear regression equation was PCT_{venous serum}=0.135+0.929×PCT_{peripheral whole blood}. However, when stratified to 5 levels, PCT results showed diverse and unsatisfied consistency between the two sampling methods (r=0.51-0.92, all P<0.01). But after PCT was converted to ordinal categorical variables, the stratified analysis showed that the coincidence rate of the measured values by the two sampling methods in each boundary area was 84.9%-97.1%. The dichotomous variables also showed a good consistency (coincidence rate 96.8%-99.3%, Youden index 0.82-0.89). According to the severity of disease, the serum PCT value was classified into 4 intervals（<0.5、0.5-<2.0、2.0-<10.0、≥10.0 μg/L）, and the peripheral blood PCT value also showed a good predictive value (AUC value was 0.991 2-0.997 9). The optimal cut points of peripheral whole blood PCT value 0.5、1.0、2.0、10.0 μg/L corresponding to venous serum PCT values were 0.395, 0.595, 1.175 and 3.545 μg/L, respectively. Conclusions: There is a good correlation between peripheral whole blood PCT value and the venous serum PCT value, which means that the peripheral whole blood PCT could facilitate the identification of infection and clinical severity. Besides, the sampling of peripheral whole blood is simple and easy to repeat.

Insight into intrinsic ferromagnetism in quasi-2D Cr5-yTe8

Cr₅Te₈is a half metal with 2D van der Waals ferromagnetic structure and its magnetic properties can be tuned by changing the proportionality of Cr and Te. We report an investigation of magnetization and magnetic anisotropy near the critical transition region of a Cr_5-yTe₈single crystal with the static and dynamic probes, to unravel the nature of field-dependent spin-spin interactions. The magnetic transition temperatureT_Cincreasing from 255 K (at near zero-field) to 279 K (at 65 kOe along theab-plane) has been identified. Accordingly, a phase diagram of field versus transition temperature has been established. From the analysis of the field dependence of the critical behavior, we provided evidence that the scenario of 2D Heisenberg-type interactions can be employed to interpret the field-dependent magnetic transitions in Te-rich Cr_4.8Te₈. The precise picture for the field-reduced spin-spin interaction range has been obtained. The conclusion drawn from the present study demonstrated that Cr_4.8Te₈is a promising candidate for the spintronic applications with a tunable magnetic transition temperature.

Inherited Human XY Sex Reversal and Gonadal Neoplasia Due to Enhanced Formation of Non-Specific Enhanceosomes by an Architectural Transcription Factor

The development of organisms is regulated by a fine-tuned gene-regulatory network, which is driven by transcription factors (TFs). In the embryogenesis, these TFs control diverse cell fates and final body plan. This is precisely regulated by a specific DNA-binding process and enhanceosome formation. A model is provided by testis determination in mammals, which is initiated by a Y-encoded architectural transcription factor, SRY. Mutations in SRY cause gonadal dysgenesis leading to various developmental defects. Such mutations cluster in SRY’s high mobility group (HMG) box, a sequence-specific DNA-binding domain shared by a conserved family of TFs. Here, we have characterized several mutations at the same position in HMG box, which are compatible with either male or female phenotypes as observed in an XY father and XY daughter, respectively. These mutations, at a function-unknown motif in the SRY HMG box, markedly disturb the specific DNA affinity. On transient transfection of human and rodent cell lines, the SRY variants exhibit decreased specific DNA-binding activity (relative to wild type) are associated with mis-formed enhanceosomes. The variants’ gene regulatory activities were reduced by 2-fold relative to wild-type SRY at similar levels of mRNA expression. When engineered mutations that functions to increase the DNA-binding specificity were deployed to SRY variants, the transcriptional activity was in association with restored occupancy of sex-specific enhancer elements in principal downstream gene Sox9. Our findings define a novel mechanism of impaired organogenesis, disturbed specific DNA-binding activity of a master transcription factor, leading to a developmental decision poised at the edge of ambiguity.

Insertion of a Synthetic Switch Into Insulin Provides Metabolite-Dependent Regulation of Hormone-Receptor Activation

Insulin signaling requires conformational change: whereas the free hormone and its receptor each adopt autoinhibited conformations, their binding leads to large-scale structural reorganization. To test the coupling between insulin’s “opening” and receptor activation, we inserted an artificial ligand-dependent switch into insulin. Ligand binding disrupts an internal tether designed to stabilize the hormone’s native closed and inactive conformation, thereby enabling productive receptor engagement. This scheme exploited a diol sensor (meta-fluoro-phenylboronic acid at GlyA1) and internal diol (3,4-dihydroxybenzoate at LysB28). The sensor recognizes monosaccharides (fructose > glucose). Studies of insulin signaling in human hepatoma-derived cells (HepG2) demonstrated fructose-dependent receptor autophosphorylation leading to appropriate downstream signaling events, including a specific kinase cascade and metabolic gene regulation (gluconeogenesis and lipogenesis). Addition of glucose (an isomeric ligand with negligible sensor affinity) did not activate the receptor. Similarly, metabolite-regulated signaling was not observed in control studies of (i) an unmodified insulin analog or (ii) an analog containing a diol sensor in the absence of internal tethering. Although as expected CD-detected secondary structure was unaffected by ligand binding, heteronuclear NMR studies revealed subtle local and nonlocal monosaccharide-dependent changes in structure. Insertion of a synthetic switch into insulin has thus demonstrated coupling between hinge-opening and holoreceptor signaling. In addition to this basic finding, our results provide proof of principle for a mechanism-based metabolite-responsive insulin. In particular, replacement of the present fructose sensor by an analogous glucose sensor may enable translational development of a “smart” insulin analog designed to mitigate risk of hypoglycemia in the treatment of diabetes mellitus.

Diabetes mellitus due to toxic misfolding of proinsulin variants

BACKGROUND

Dominant mutations in the human insulin gene (INS) lead to pancreatic β-cell dysfunction and diabetes mellitus (DM) due to toxic misfolding of a mutant proinsulin. Analogous to a classical mouse model of monogenic DM ("Akita"), this syndrome highlights the susceptibility of β-cells to endoreticulum (ER) stress due to protein misfolding and aberrant aggregation.

SCOPE OF REVIEW

Diverse clinical mutations directly or indirectly perturb native disulfide pairing. Whereas most introduce or remove a cysteine (Cys; leading in either case to an unpaired thiol group), non-Cys-related mutations identify key determinants of folding efficiency. Studies of such mutations suggest that the hormone's evolution has been constrained not only by structure-function relationships but also by the susceptibility of its single-chain precursor to impaired foldability. An intriguing hypothesis posits that INS overexpression in response to peripheral insulin resistance likewise leads to chronic ER stress and β-cell dysfunction in the natural history of nonsyndromic Type 2 DM.

MAJOR CONCLUSIONS

Cryptic contributions of conserved residues to folding efficiency, as uncovered by rare genetic variants, define molecular links between biophysical principles and the emerging paradigm of Darwinian medicine: Biosynthesis of proinsulin at the edge of nonfoldability provides a key determinant of "diabesity" as a pandemic disease of civilization.

Effect of congenital heart disease on the recurrence of cough variant asthma in children

Background

The research into the recurrence of cough variant asthma (CVA) in congenital heart disease (CHD) are few in number. The purpose of this study is to investigate the effect of CHD on the risk of the recurrence of CVA.

Methods

This study was a retrospective cohort study of 489 children with CVA aged between one and 14 years, of whom 67 had CHD complicated with CVA and 134 had CVA without CHD at a ratio of 1:2 according to age, sex and index year. The adjusted hazard ratio (aHR) of CVA recurrence in both the CHD cohort and the non-CHD cohort was determined by multivariate analysis using the Cox proportional hazard regression model.

Results

Adjusting for CHD classification, Mycoplasma pneumonia (MP) infection and immunoglobulin E (IgE) sensitization, the recurrence hazard of CVA in the complex congenital heart disease (CCHD) group (aHR = 3.281; 95% CI 1.648–6.530; P < 0.01) was significantly higher than that in the simple congenital heart disease group (aHR = 2.555; 95% CI 1.739–3.752; P < 0.01). Further, children with IgE sensitization (aHR = 2.172; 95% CI 1.482–3.184; P < 0.01) had a higher recurrence hazard of CVA than those without IgE sensitization, and children with MP infection (aHR = 1.777; 95% CI 1.188–2.657; P < 0.01) had a higher recurrence hazard of CVA than those without the MP infection.

Conclusion

The hazard of recurrent CVA is higher in children with CHD, especially in the CCHD children. In addition, those children with IgE sensitization or a MP infection had an increased hazard of recurrent CVA.

[An analysis of mortality trends for lung cancer during 1972-2016 in Qidong city of Jiangsu Province]

Crude mortality rate (CR) for lung cancer in Qidong increased from 11.50/10⁵ in 1972-1976 to 76.61/10⁵ in 2012-2016, China age-standardized rate (CASR) from 13.11/10⁵ in 1972-1976 to 34.27/10⁵ in 2012-2016, and World age-standardized rate (WASR) from 13.40/10⁵ in 1972-1976 to 34.30/10⁵ in 2012-2016. The average annual percentage change (AAPCs) of CR, CASR, WASR were 4.87% (95%CI: 4.63%-5.12%), 2.17% (95%CI: 1.96%-2.38%), 2.12% (95%CI: 1.92%-2.33%) (all P values<0.001), respectively. AAPCs for 45-54, 55-64, 65-74 and over 75 age groups were 0.74% (95%CI: 0.36%-1.11%), 1.23% (95%CI: 0.92%-1.53%), 2.55% (95%CI: 2.20%-2.90%), 4.26% (95%CI: 3.56%-4.96%) (all P values<0.001), respectively.

Evolution of insulin at the edge of foldability and its medical implications

Proteins have evolved to be foldable, and yet determinants of foldability may be inapparent once the native state is reached. Insight has emerged from studies of diseases of protein misfolding, exemplified by monogenic diabetes mellitus due to mutations in proinsulin leading to endoplasmic reticulum stress and β-cell death. Cellular foldability of human proinsulin requires an invariant Phe within a conserved crevice at the receptor-binding surface (position B24). Any substitution, even related aromatic residue TyrB24, impairs insulin biosynthesis and secretion. As a seeming paradox, a monomeric TyrB24 insulin analog exhibits a native-like structure in solution with only a modest decrement in stability. Packing of TyrB24 is similar to that of PheB24, adjoining core cystine B19-A20 to seal the core; the analog also exhibits native self-assembly. Although affinity for the insulin receptor is decreased ∼20-fold, biological activities in cells and rats were within the range of natural variation. Together, our findings suggest that the invariance of PheB24 among vertebrate insulins and insulin-like growth factors reflects an essential role in enabling efficient protein folding, trafficking, and secretion, a function that is inapparent in native structures. In particular, we envision that the para-hydroxyl group of TyrB24 hinders pairing of cystine B19-A20 in an obligatory on-pathway folding intermediate. The absence of genetic variation at B24 and other conserved sites near this disulfide bridge-excluded due to β-cell dysfunction-suggests that insulin has evolved to the edge of foldability. Nonrobustness of a protein's fitness landscape underlies both a rare monogenic syndrome and "diabesity" as a pandemic disease of civilization.

[Health economic evidence for colorectal cancer screening programs in China: an update from 2009-2018]

Objective: This study was to systematically update the economic evaluation evidence of colorectal cancer screening in mainland China. Methods: Based on a systematic review published in 2015, we expanded the scope of retrieval database (PubMed, EMbase, The Cochrane Library, Web of Science, CNKI, Wanfang Data, VIP, CBM) and extended it to December 2018. Focusing on the evidence for nearly 10 years (2009-2018), basic characteristics and main results were extracted. Costs were discounted to 2017 using the consumer price index of medical and health care being provided to the residents, and the ratio of incremental cost-effectiveness ratio (ICER) to per capita GDP in corresponding years were calculated. Results: A total of 12 articles (8 new ones) were included, of which 9 were population-based (all cross-sectional studies) and 3 were model-based. Most of the initial screening age was 40 years (7 articles), and most of the frequency was once in a lifetime (11 articles). Technologies used for primary screening included: questionnaire assessment, immunological fecal occult blood test (iFOBT) and endoscopy. The most commonly used indicator was the cost per colorectal cancer detected, and the median (range) of the 20 screening schemes was 52 307 Chinese Yuan (12 967-3 769 801, n=20). The cost per adenoma detected was 9 220 Yuan (1 859-40 535, n=10). In 3 articles, the cost per life year saved (compared with noscreening) was mentioned and the ratio of ICER to GDP was 0.673 (-0.013-2.459, n=11), which was considered by WHO as "very cost-effective" ; The range of ratios overlapped greatly among different technologies and screening frequencies, but the initial age for screening seemed more cost-effective at the age of 50 years (0.002, -0.013-0.015, n=3), than at the 40 year-olds (0.781, 0.321-2.459, n=8). Conclusions: Results from the population-based studies showed that the cost per adenoma detected was only 1/6 of the cost per colorectal cancer detected, and limited ICER evidence suggested that screening for colorectal cancer was generally cost-effective in Chinese population. Despite the inconclusiveness of the optimal screening technology, the findings suggested that the initial screening might be more cost-effective at older age. No high-level evidence such as randomized controlled trial evaluation was found.

SUN-712 Familial 46, XY Complete Female External Sex Development with a Non-Mosaic Inherited SRY Gene Variation

Context: SRY, an architectural transcription factor containing a SOX-related high-mobility group (HMG) box, initiates testis formation in the mammalian bipotential gonadal ridge. Inherited human SRY mutations can be associated with differences in sexual differentiation (DSD) with variable phenotypes in a family.

Objective: To describe the clinical, histopathological and molecular features of a novel inherited SRY allele (pMet64Val; consensus box position 9) observed within an extensive pedigree: two 46, XY sisters with primary amenorrhea (16 and 14 years of age; probands P1 and P2), their normal father and brother, and an affected paternal XY grandaunt.

Design, Setting, Participants and Outcome Measurements: Following DNA sequencing to identify the SRY mutation, hormonal studies of the probands and histopathological examination of their gonads were performed. Functional consequences of p.Met64Val (and other mutations at this site) were also investigated.

Results: Breast development in P1 and P2was Tanner II and IV, respectively. Müllerian structures and gonads resembling ovaries were found in each sister. Histopathology revealed gonadal dysgenesis, gonadoblastoma and dysgerminoma. AMH/MIS, P450 SCC, and P450 aromatase were expressed in gonadoblastoma tissues. Variant p.Met64Val impaired Sox9 transcriptional activation associated with attenuated occupancy of the testis-specific enhancersEnh13 and TESCO.

Conclusion: The partial biological activity of p.Met64Val SRY, maintained at the threshold of SRY function, rationalizes opposing paternal and proband phenotypes (the “the father-daughter paradox”).Sex steroids biosynthesis by gonadoblastoma may delay genetic diagnosis and recognition of gonadal tumors. Quantitative assessment of inherited SRY alleles highlights the tenuous transcriptional threshold of developmental decision-making in the bipotential gonadal ridge.

Reassessment of an Innovative Insulin Analogue Excludes Protracted Action yet Highlights the Distinction between External and Internal Diselenide Bridges

Long-acting insulin analogues represent the most prescribed class of therapeutic proteins. An innovative design strategy was recently proposed: diselenide substitution of an external disulfide bridge. This approach exploited the distinctive physicochemical properties of selenocysteine (U). Relative to wild type (WT), Se-insulin[C7U^A , C7U^B ] was reported to be protected from proteolysis by insulin-degrading enzyme (IDE), predicting prolonged activity. Because of this strategy's novelty and potential clinical importance, we sought to validate these findings and test their therapeutic utility in an animal model of diabetes mellitus. Surprisingly, the analogue did not exhibit enhanced stability, and its susceptibility to cleavage by either IDE or a canonical serine protease (glutamyl endopeptidase Glu-C) was similar to WT. Moreover, the analogue's pharmacodynamic profile in rats was not prolonged relative to a rapid-acting clinical analogue (insulin lispro). Although [C7U^A , C7U^B ] does not confer protracted action, nonetheless its comparison to internal diselenide bridges promises to provide broad biophysical insight.

"Register-shift" insulin analogs uncover constraints of proteotoxicity in protein evolution

Globular protein sequences encode not only functional structures (the native state) but also protein foldability, i.e. a conformational search that is both efficient and robustly minimizes misfolding. Studies of mutations associated with toxic misfolding have yielded insights into molecular determinants of protein foldability. Of particular interest are residues that are conserved yet dispensable in the native state. Here, we exploited the mutant proinsulin syndrome (a major cause of permanent neonatal-onset diabetes mellitus) to investigate whether toxic misfolding poses an evolutionary constraint. Our experiments focused on an invariant aromatic motif (Phe^B24-Phe^B25-Tyr^B26) with complementary roles in native self-assembly and receptor binding. A novel class of mutations provided evidence that insulin can bind to the insulin receptor (IR) in two different modes, distinguished by a "register shift" in this motif, as visualized by molecular dynamics (MD) simulations. Register-shift variants are active but defective in cellular foldability and exquisitely susceptible to fibrillation in vitro Indeed, expression of the corresponding proinsulin variant induced endoplasmic reticulum stress, a general feature of the mutant proinsulin syndrome. Although not present among vertebrate insulin and insulin-like sequences, a prototypical variant ([Gly^B24]insulin) was as potent as WT insulin in a rat model of diabetes. Although in MD simulations the shifted register of receptor engagement is compatible with the structure and allosteric reorganization of the IR-signaling complex, our results suggest that this binding mode is associated with toxic misfolding and so is disallowed in evolution. The implicit threat of proteotoxicity limits sequence variation among vertebrate insulins and insulin-like growth factors.

Identification of the New Psychoactive Substance Dibutylone

Abstract

Objective To establish a method to identify unknown samples based on combined use of gas chromatography-mass spectrometry （GC-MS）, high resolution mass spectrometry （HRMS） and nuclear magnetic resonance spectrum （NMR） technique. Methods The unknown samples were dissolved in methanol solution containing internal standard SKF525A and detected by GC-MS and HRMS. The mixed samples were separated and purified by silica gel column chromatography, and then dissolved in methanol-d4 solution for structural analysis of ¹H nuclear magnetic resonance spectroscopy （¹H NMR）. Results The characteristic fragment ions （m/z） were 86.1 （base peak）, 71.2, 121.1, and 149.0, and the accurate mass number of molecular ion peak was measured by HRMS to be 236.128 89. By combined use of data analysis and database comparison, a new psychoactive substance of the cathinone class, Dibutylone, was detected in the sample, and the sample also contained a small amount of caffeine. The sample was purified, then identified using ¹H NMR, and was further confirmed to be Dibutylone. In addition, the GC-MS retention time and characteristic fragment ions of the main components of the sample were consistent with those of Dibutylone reference material. Conclusion The method established in this study can be used for the identification of Dibutylone in mixed samples.

[Study on the health literacy and related factors of the cancer prevention consciousness among urban residents in China from 2015 to 2017]

Objective: To understand the health literacy and relevant factors of cancer prevention consciousness in Chinese urban residents from 2015 to 2017. Methods: A cross-sectional survey was conducted in 16 provinces covered by the Cancer Screening Program in Urban China from 2015 to 2017. A total of 32 257 local residents aged ≥18 years old who could understand the investigation procedure were included in the study by using the cluster sampling method and convenient sampling method. All local residents were categorized into four groups, which contained 15 524 community residents, 8 016 cancer risk assessment/screening population, 2 289 cancer patients and 6 428 occupational population, respectively. The self-designed questionnaire was used to collect the information of demographic characteristics and cancer prevention consciousness focusing on nine common risk factors, including smoking, alcohol, fiber food, food in hot temperature or pickled food, chewing betel nut, helicobacter pylori, moldy food, hepatitis B infection, estrogen, and exercise. The logistic regression model was adopted to identify the influencing factors. Results: The overall health literacy of the cancer prevention consciousness was 77.4% (24 980 participants), with 77.4% (12 018 participants), 79.9% (6 406 participants), 77.2% (1 766 participants) and 74.5% (4 709 participants) in each group (P<0.001). The correct response rates for nine risk factors ranged from 55.2% to 93.0%. The multivariate logistic regression analysis showed that compared with community residents, people with primary school level education or below, and the number of people living together in the family <3, the cancer risk assessment/screening intervention population, cancer patients, those with junior high school level educationor above and the number of people living in the family ≥3 had better health literacy of the cancer prevention consciousness (all P values <0.05). Compared with females, 39 years old and below, government-affiliated institutions or civil servants, from the eastern region, males, older than 40 years, company or enterprise employees, and from the middle or western region had worse health literacy of the cancer prevention consciousness (all P values <0.05). Conclusion: The health literacy of the cancer prevention consciousness in Chinese urban residents should be improved. The cancer screening intervention, gender, age, education, occupation, the number of people co-living in the family, and residential region were associated with the health literacy of the cancer prevention consciousness.

P38 Developing a model for predicting in-hospital death in patients with the use of extracorporeal membrane oxygenation

Funding Acknowledgements

Minister of Science and Technology

Background

The objective of this study was to develop a predicting model for estimating the odds of in-hospital death in the patients who receive extracorporeal membrane oxygenation (ECMO).

Methods

Adult patients who received ECMO for a variety of etiologies in our National University Hospital from 2005 and 2016 were included. The demographic, anthropometric, hemodynamic, and laboratory data when ECMO was instituted were recorded for each individual. A logistic regression model was applied to find the risk variables that were independently associated with in-hospital mortality. The predicted probability derived from the model was used to plot a receiver-operating-characteristic (ROC) curve, and area under curve (AUC) was found to represent the differentiating capacity of this approach.

Results

A total of 919 patients (659 men and 260 women) were included in the analysis. The mean age was 53.7[SD 15.9] years. The analysis showed that age (odds ratio [OR]: 1.018, 95% confidence interval [CI]: 1.008-1.028 per year), blood urea nitrogen (1.008 [1.001-1.014] per mg/dL), use of inotropic agent in terms of inotropic equivalent (1.007 [1.002-1.013]), the presence of cardiogenic shock (1.910 [1.097-3.327]), and the need of hemodialysis (2.262 [1.304-3.926]) were positively associated with mortality. In addition, body surface area (OR: 0.414 [0.204-0.840] per square meter), systolic blood pressure (0.995 [0.990-0.999] per mmHg), Glasgow Coma Scale (0.928 [0.899-0.957] per unit), pH value (0.395 [0.158-0.988] for each unit), and urine output (OR: 0.974 [0.964-0.985] per dL) were negatively associated with the probability of in-hospital death. The AUC in ROC analysis was 0.754 (95% CI: 0.722-0.787).

Conclusion

The predicting model that used a simple set of physiological parameters could substantially discriminate whether the patients receiving ECMO could survive the in-hospital course. Further studies are needed to examine why false positive and false negative predictions took place.

Abstract P38 Figure.

[Association of glycosylated hemoglobin level at admission with outcomes of intracerebral hemorrhage patients]

Objective: To explore the association of the glycosylated hemoglobin (HbA1c) level at admission with 90 days functional outcome in patients with spontaneous intracerebral hemorrhage (ICH). Methods: Patients admitted to the Department of Neurology, Tongji Hospital from January to December 2017 were prospectively and continuously enrolled in this study. Clinical data were collected at admission and functional outcomes 90 days after ICH were assessed by using the modified RANKIN scale. Univariate and multivariate conditional logistic regression models were constructed. Patients were divided into four groups according to the quartile of HbA1c values. The median value of HbA1c in each group was taken as the substitute value and P for trend was calculated. The logistic regression model was fitted by restricted cubic splines to investigate the association between HbA1c level and outcome of ICH. Results: A total of 345 patients with ICH were enrolled, including 214 with favorable outcomes and 131 with poor outcomes (99 severe disability cases and 32 deaths). The risk of poor 90 days outcomes was significantly associated with HbA1c level at admission indicated by multivariate logistic regression analysis, and the P for trend test was <0.001 (middle-level group vs. low-level group: OR=2.33, 95%CI: 1.07-5.07; high-level group vs. low-level group: OR=2.52, 95%CI: 1.12-5.64; extremely high-level group vs. low-level group: OR=6.80, 95%CI: 3.01-15.34). Results from the restricted cubic spline showed that there was a linear correlation between HbA1c level at admission and poor 90 days outcomes of ICH (χ(2)=14.81, P<0.001; non- linear test: P=0.118). Compared with patients with HbA1c level of 6.5%, the risk of poor outcomes in patients with HbA1c level of <6.5% decreased linearly with the decrease in HbA1c level at admission, and the risk in patients with HbA1c level >6.5% was higher but not significantly. Conclusion: There was correlation between high HbA1c level at admission and 90 days poor outcome of ICH. High HbA1c level is an independent prediction indicator for ICH.

Singlet exciton fission via an intermolecular charge transfer state in coevaporated pentacene-perfluoropentacene thin films

Singlet exciton fission is a spin-allowed process in organic semiconductors by which one absorbed photon generates two triplet excitons. Theory predicts that singlet fission is mediated by intermolecular charge-transfer states in solid-state materials with appropriate singlet-triplet energy spacing, but direct evidence for the involvement of such states in the process has not been provided yet. Here, we report on the observation of subpicosecond singlet fission in mixed films of pentacene and perfluoropentacene. By combining transient spectroscopy measurements to nonadiabatic quantum-dynamics simulations, we show that direct excitation in the charge-transfer absorption band of the mixed films leads to the formation of triplet excitons, unambiguously proving that they act as intermediate states in the fission process.

[Screening function enrichment and related signaling pathways bioinformatics analysis of differentially expressed gene in glioma]

Objective: To screen the differentially expressed genes, functional enrichment and related signaling pathways in glioma by bioinformatics analysis. Methods: Microarray data of glioma related gene expression profiles were selected in GEO database, and differentially expressed genes in glioma patients and normal brain tissues were screened by R statistical software of lima package. Functional enrichment of differentially expressed genes (GO and KEGG) was performed. The protein-protein interaction database (STRING) was used to analyze the interaction between the screened differentially expressed genes and the related signaling pathways. Results: Two gene expression profiles, GSE15824 and GSE66354, were selected for analysis, and 158 genes with differential expression more than 2 times and P<0.05 were screened. Molecular function (MF) of 158 differentially expressed genes was integrin binding, cell adhesion molecule binding, calcium binding and AMPA glutamate receptor activity. Cell component localization (CC) was located in cell membrane, neuron cell body, axon of nerve cell and so on, while biological process (BP) was mainly cell adhesion and nervous system. Development, cell proliferation, GTPase activity, apoptosis and angiogenesis; KEGG signaling pathways were mainly cAMP signaling pathway, purine metabolism pathway, MAPK signaling pathway and cGMP-PKG signaling pathway. There were 177 interaction connections in 158 differential expression gene-protein interaction networks, with an average interaction of 2.39 between each node and an aggregation coefficient of 0.37. Cytohubb screened the key genes (hub genes) in the signaling pathway. The results indicated that SLC6A1,SLC1A2,BDNF,GAP43,NRXN1,GAD1,OLIG2, PLP1,S100B and GRIA3 were the key genes in the signaling pathway of the interacting protein network. All the 10 key genes were related to the prognosis of patients (P<0.05). Conclusions: There are differentially expressed genes profile in glioma tissues and normal tissues. SLC6A1, SLC1A2, BDNF, GAP43, NRXN1, GAD1, OLIG2, PLP1, S100B and GRIA3 are key genes for glioma development and are related to the prognosis of patients.

OR15-5 Human Sex Determination at the Edge of Ambiguity: Impaired SRY Phosphorylation Attenuates Expression of the Male Program

A paradox is posed by metazoan gene-regulatory networks (GRNs) that are robust yet evolvable. Insight may be obtained through studies of bistable genetic circuits mediating developmental decisions. A model in organogenesis is provided by the sex-specific differentiation of the embryonic gonadal ridge to form a testis or ovary. Here, we investigated a Swyer mutation in human testis-determining factor SRY that impairs its phosphorylation in association with variable developmental outcomes: fertile male, intersex, or infertile female (46, XY pure gonadal dysgenesis). The mutation (R30I) abrogates serine phosphorylation within a putative target site for protein kinase A (PKA) N-terminal to the HMG box. Diverse processes can be regulated by protein phosphorylation, including DNA recognition by transcription factors (TFs). Phosphorylation of this site in human SRY (LRRSSSFLCT; italics) in vitro was previously shown to enhance specific DNA affinity. Biological consequences of the mutation were evaluated in SRY-responsive mammalian cell lines following transient transfection. The mutation attenuated in concert occupancy of a target enhancer (TESCO) and SOX9 transcriptional activation. These perturbations were mitigated by acidic substitution (LRIDDDFL) whereas Ala substitutions (RRAAAFL or RIAAAFL) attenuated activity to an extent similar to R30I alone. No differences were observed in nuclear localization. Mutagenesis suggested that the central Ser is most efficiently phosphorylated in accord with PKA targeting rules. Replacement of the native site by an optimized “Kemptide” PKA site (LRRASLGCT) enhanced both SRY phosphorylation and SOX9 transcriptional activation whereas a “swapped” protein-kinase C determinant (LRRSSFRRCT) blocked phosphorylation. Among SRY variants, extent of cellular phosphorylation mirrored relative in vitro efficiencies of synthetic SRY-derived peptides as PKA-specific substrates. Although several kinases are predicted in silico to target this tri-serine motif, cell-based studies implicate PKA as the relevant kinase in vivo. Our results provide evidence that primate Sry requires its phosphorylation for full gene-regulatory activity. A PKA site N-terminal to the SRY HMG box, unique to primates, exemplifies network “tinkering” through recruitment of a new regulatory linkage. Molecular characterization of the R30I inherited Swyer mutation in SRY thus demonstrates that impaired TF phosphorylation can attenuate a human developmental switch at the edge of ambiguity.

[Etiological analysis and establishment of a discriminant model for lower respiratory tract infections in hospitalized patients]

Objective: To analyze the pathogens of lower respiratory tract infection(LRTI) including bacterial, viral and mixed infection, and to establish a discriminant model based on clinical features in order to predict the pathogens. Methods: A total of 243 hospitalized patients with lower respiratory tract infections were enrolled in Fujian Provincial Hospital from April 2012 to September 2015. The clinical data and airway (sputum and/or bronchoalveolar lavage) samples were collected. Microbes were identified by traditional culture (for bacteria), loop-mediated isothermal amplification(LAMP) and gene sequencing (for bacteria and atypical pathogen), or Real-time quantitative polymerase chain reaction (Real-time PCR)for viruses. Finally, a discriminant model was established by using the discriminant analysis methods to help to predict bacterial, viral and mixed infections. Results: Pathogens were detected in 53.9% (131/243) of the 243 cases.Bacteria accounted for 23.5%(57/243, of which 17 cases with the virus, 1 case with Mycoplasma pneumoniae and virus), mainly Pseudomonas Aeruginosa and Klebsiella Pneumonia. Atypical pathogens for 4.9% (12/243, of which 3 cases with the virus, 1 case of bacteria and viruses), all were mycoplasma pneumonia. Viruses for 34.6% (84/243, of which 17 cases of bacteria, 3 cases with Mycoplasma pneumoniae, 1 case with Mycoplasma pneumoniae and bacteria) of the cases, mainly Influenza A virus and Human Cytomegalovirus, and other virus like adenovirus, human parainfluenza virus, respiratory syncytial virus, human metapneumovirus, human boca virus were also detected fewly. Seven parameters including mental status, using antibiotics prior to admission, complications, abnormal breath sounds, neutrophil alkaline phosphatase (NAP) score, pneumonia severity index (PSI) score and CRUB-65 score were enrolled after univariate analysis, and discriminant analysis was used to establish the discriminant model by applying the identified pathogens as the dependent variable. The total positive predictive value was 64.7%(77/119), with 66.7% for bacterial infection, 78.0% for viral infection and 33.3% for the mixed infection. Conclusions: The mostly detected pathogens were Pseudomonas aeruginosa, atypitcal pathogens, Klebsiella pneumoniae, influenza A virus and human cytomegalovirus in hospitalized patients with LRTI in this hospital. The discriminant diagnostic model established by clinical features may contribute to predict the pathogens of LRTI.

[Application of cervical lifting suture in hemostasis of placenta previa with increta and percreta]

Objective: To evaluate the effect of cervical lifting suture in treatment of placenta previa with increta and percreta. Methods: From January 2016 to June 2017, 65 cases (0.78%, 65/8 322) were diagnosed placenta previa with increta and percreta by prenatal ultrasonic score system and confirmed by intraoperative findings in the department of obstetrics and gynecology of Peking University Third Hospital. Totally 62 cases (0.75%, 62/8 322) were included, because 3 cases underwent hysterectomy with placenta in situ. According to ultrasonic score system, 62 cases were divided into two groups, score 5-9 group (n=42, 67.7%) and score≥10 group (n=20, 32.3%) , cervical lifting suture techniques were all performed in cesarean sections. Demographic and clinical data were collected and compared. Results: (1) There were no significant differences between two groups in age, gravidity, parity, cesarean section history ratio and gestational week of termination (all P>0.05) . (2) In score≥10 group, the median intraoperative bleeding volume was 4 000 ml (1 200-13 000 ml) , while in score 5-9 group, it was 1 600 ml (700-10 000 ml) , intraoperative blood transfusion volume was 2 000 ml (800-8 800 ml) in score≥10 group, while 1 200 ml (0-8 000 ml) in score 5-9 group. The median operation time was 240 minutes (108-1 200 minutes) in score≥10 group, significantly higher than that in score 5-9 group, which was 135 minutes (69-335 minutes; all P< 0.05). In 8 cases for hysterectomy (12.9%,8/62) , 3 cases in score 5-9 group, 5 cases in score≥10 group. (3) In score≥10 group, the rate of postoperative ICU registration was 80% and mean hospitalization time was (6.3±1.7) days, were significantly different, compared with those in score 5-9 group, which were 26%, (4.9±1.9) days. No serious postpartum complications were found in both groups, and there were no significant differences in Apgar score and weight of newborns (all P>0.05) . Conclusion: Cervical lifting suture in placenta previa with increta and percreta could significantly reduce postpartum hemorrhage and retain uterine.

[Early diagnosis and early treatment for liver cancer in Qidong: survival of patients and effectiveness of screening]

Objective: To evaluate the patients' survival and effectiveness of the live cancer screening for population at high risk for liver cancer in Qidong. Methods: According to the Expert Scheme proposed the Expert Committee of Early Detection and Early Treatment, China Cancer Foundation, diagnostical screening by using combined methods of alpha-fetoprotein and B ultrasound monitoring were carried out biannually in individuals with positive HBsAg who were screened from Qidong area. The evaluation indices of the effectiveness are task completion rate of screening, detection rate of liver cancer, early diagnosis rate, and treatment rate. The deadline of the follow-up for the surviving outcome was March 31, 2016. The life-table method was used to calculate the observed survival, and to make comparison and significant tests between survival rates in Group A (those found via repeated periodic screening) and Group B (those diagnosed without periodic screening). Results: Since 2007, 38 016 target population have been screened, and 3 703(9.74%) individuals with positive HBsAg were found. Except for 29 patients with liver cancer at the initial screening, 3 674 persons in the cohort were followed up; 268 patients with liver cancer were detected from the 33 199 person-times screening, with an annual detection rate of 1.61%. Of them, 186 patients were found in Group A(1.12%), in which 149 patients were the early cases, with an early detection rate of 80.11%; 167 out of 186(89.78%) patients received treatment after diagnosis. The incidence of liver cancer in this HBsAg (+ ) cohort of 25 452 person-years was 1 052.96 per 100 000 annually, 187 cases in males(1 488.45/100 000)and 81 cases in females(628.46/100 000). The 1-, 3-, 5-, and 8-year survival of all patients with liver cancer were 64.55%, 40.50%, 32.54%, and 19.65%, respectively. The 1-, 3-, 5-, and 8-year survival rates were 77.16%, 49.04%, 38.53%, and 24.25% in Group A, and were 36.25%, 21.21%, 21.21%, and 0% in Group B, respectively, with significant differences between two groups (P<0.05). Conclusion: The findings show that screening of individuals at high-risk of development of liver cancer, with semiannual AFP and B ultrasound, according to the Expert Scheme, is effective not only in increasing detection rate but also in detecting liver cancer at early stage, and in improving patients' survival as well.

An ultra-stable single-chain insulin analog resists thermal inactivation and exhibits biological signaling duration equivalent to the native protein

Thermal degradation of insulin complicates its delivery and use. Previous efforts to engineer ultra-stable analogs were confounded by prolonged cellular signaling in vivo, of unclear safety and complicating mealtime therapy. We therefore sought an ultra-stable analog whose potency and duration of action on intravenous bolus injection in diabetic rats are indistinguishable from wild-type (WT) insulin. Here, we describe the structure, function, and stability of such an analog, a 57-residue single-chain insulin (SCI) with multiple acidic substitutions. Cell-based studies revealed native-like signaling properties with negligible mitogenic activity. Its crystal structure, determined as a novel zinc-free hexamer at 2.8 Å, revealed a native insulin fold with incomplete or absent electron density in the C domain; complementary NMR studies are described in the accompanying article. The stability of the analog (ΔG_U 5.0(±0.1) kcal/mol at 25 °C) was greater than that of WT insulin (3.3(±0.1) kcal/mol). On gentle agitation, the SCI retained full activity for >140 days at 45 °C and >48 h at 75 °C. These findings indicate that marked resistance to thermal inactivation in vitro is compatible with native duration of activity in vivo Further, whereas WT insulin forms large and heterogeneous aggregates above the standard 0.6 mm pharmaceutical strength, perturbing the pharmacokinetic properties of concentrated formulations, dynamic light scattering, and size-exclusion chromatography revealed only limited SCI self-assembly and aggregation in the concentration range 1-7 mm Such a combination of favorable biophysical and biological properties suggests that SCIs could provide a global therapeutic platform without a cold chain.