High coherence collapse of a hybrid III–V/Si semiconductor laser with a large quality factor

The high-speed dynamics of a hybrid distributed feedback semiconductor laser heterogeneously integrated onto silicon is experimentally investigated in the presence of external optical feedback. The laser fabrication relies on a proper modal engineering in which light is generated in the III–V material and stored in the low-loss silicon region in order to substantially enhance the quality factor of the cavity resonator. In this work, the hybrid laser is found to be insensitive to parasitic reflections leading to a 10 Gbps floor-free transmission with a power penalty no greater than 1.5 dB at room temperature. As a conclusion, owing to the large quality factor, a high coherence collapse level is unveiled in such laser indicating its vast potential to serve as an alternative solution for the development of isolator-free applications in future photonics integrated circuits. A qualitative interpretation is also provided by linking the standard feedback equations to the quality factor of the resonator.

Gut Microbial Signatures Can Discriminate Unipolar from Bipolar Depression

Discriminating depressive episodes of bipolar disorder (BD) from major depressive disorder (MDD) is a major clinical challenge. Recently, gut microbiome alterations are implicated in these two mood disorders; however, little is known about the shared and distinct microbial characteristics in MDD versus BD. Here, using 16S ribosomal RNA (rRNA) gene sequencing, the microbial compositions of 165 subjects with MDD are compared with 217 BD, and 217 healthy controls (HCs). It is found that the microbial compositions are different between the three groups. Compared to HCs, MDD is characterized by altered covarying operational taxonomic units (OTUs) assigned to the Bacteroidaceae family, and BD shows disturbed covarying OTUs belonging to Lachnospiraceae, Prevotellaceae, and Ruminococcaceae families. Furthermore, a signature of 26 OTUs is identified that can distinguish patients with MDD from those with BD or HCs, with area under the curve (AUC) values ranging from 0.961 to 0.986 in discovery sets, and 0.702 to 0.741 in validation sets. Moreover, 4 of 26 microbial markers correlate with disease severity in MDD or BD. Together, distinct gut microbial compositions are identified in MDD compared to BD and HCs, and a novel marker panel is provided for distinguishing MDD from BD based on gut microbiome signatures.

[Association of sleep with anxiety in the elderly aged 60 years and older in China]

Objective: To investigate the relationship of sleep duration and sleep quality with anxiety in the elderly aged 60 years and older in China. Methods: The elderly aged 60 years and older were selected from the China Short-term Health Effects of Air Pollution Study conducted between July 18, 2017 and February 7, 2018. Multivariate logistic regression models were used to analyze the association of sleep duration and sleep quality with anxiety. Results: A total of 3 897 elderly aged 60 years and older were included in the study. The age of the elderly was (73.4±8.0) years old. Among the elderly surveyed, 6.5% were defined with anxiety, and 18.7% reported poor sleep quality. Multivariate logistic regression models showed shorter sleep duration was the risk factor for anxiety in the elderly that after adjusting for factors such as general demographics, socioeconomic factors, lifestyle, health status, social support and ambient fine particulates exposure. Compared with the elderly with 7 hours of sleep duration daily, the OR (95%CI) of anxiety for those with sleep duration ≤ 6 hours was 2.09 (1.49-2.93). Compared with those with good sleep quality, the OR (95%CI) of anxiety for those with poor sleep quality was 5.12 (3.88-6.77). We also found statistically significant correlations of the scores of subscales of Pittsburgh sleep quality index with anxiety, in which the effects of sleep disturbance, subjective sleep quality and daytime dysfunction scores were most obvious, the ORs (95%CI) were 4.63 (3.55-6.04), 2.75 (2.33-3.23) and 2.50 (2.19-2.86), respectively. Subgroup analysis showed that the association of sleep duration and sleep quality with anxiety was more obvious in males and in those aged <80 years. Conclusion: Shorter sleep duration and poor sleep quality are associated with anxiety in the elderly in China.

[Prediction of 6-year incidence risk of chronic kidney disease in the elderly aged 65 years and older in 8 longevity areas in China]

Objective: To establish a prediction model for 6-year incidence risk of chronic kidney disease (CKD) in the elderly aged 65 years and older in China. Methods: In this prospective cohort study, we used the data of 3 742 participants collected during 2008/2009-2014 and during 2012-2017/2018 from Healthy Aging and Biomarkers Cohort Study, a sub-cohort of the Chinese Longitudinal Healthy Longevity Survey. Two follow up surveys for renal function were successfully conducted for 1 055 participants without CKD in baseline survey. Lasso method was used for the selection of risk factors. The risk prediction model of CKD was established by using Cox proportional hazards regression models and visualized through nomogram tool. Bootstrap method (1 000 resample) was used for internal validation, and the performance of the model was assessed by C-index and calibration curve. Results: The mean age of participants was (80.8±11.4) years. In 4 797 person years of follow up, CKD was found in 262 participants (24.8%). Age, BMI, sex, education level, marital status, having retirement pension or insurance, hypertension prevalence, blood uric acid, blood urea nitrogen and total cholesterol levels and estimated glomerular filtration rate in baseline survey were used in the model to predict the 6-year incidence risk of CKD in the elderly. The corrected C-index was 0.766, the calibration curve showed good consistence between predicted probability and observed probability in high risk group, but relatively poor consistence in low risk group. Conclusion: The incidence risk prediction model of CKD established in this study has a good performance, and the nomogram can be used as visualization tool to predict the 6-year risk of CKD in the elderly aged 65 years and older in China.

[Influencing factors for depressive symptoms in the elderly aged 65 years and older in 8 longevity areas in China]

Objective: To analyze influencing factors for depressive symptoms in the elderly aged 65 years and older in 8 longevity areas in China. Methods: We recruited 2 180 participants aged 65 years and older in 8 longevity areas from Healthy Aging and Biomarkers Cohort Study, a sub-cohort of the Chinese Longitudinal Healthy Longevity Survey in 2017. Multivariate logistic regression analysis was performed to evaluate the relationships of socio-demographic characteristics, behavioral lifestyle, chronic disease prevalence, functional status, family and social support with depressive symptoms in the elderly. Results: The detection rate of depression symptoms was 15.0% in the elderly aged 65 years and older in 8 longevity areas of China, and the detection rate of depression symptoms was 11.5% in men and 18.5% in women. Multivariate logistic regression analysis results showed that the detection rate of depressive symptoms was lower in the elderly who had regular physical exercises (OR=0.44, 95%CI: 0.26-0.74), frequent fish intakes (OR=0.57, 95%CI: 0.39-0.83), recreational activities (OR=0.65, 95%CI: 0.44-0.96), social activities (OR=0.28, 95%CI: 0.11-0.73) and community services (OR=0.68, 95%CI: 0.50-0.93). The elderly who were lack of sleep (OR=2.04, 95%CI: 1.49-2.80), had visual impairment (OR=1.54, 95%CI: 1.08-2.18), had gastrointestinal ulcer (OR=2.97, 95%CI: 1.53-5.77), had arthritis (OR=2.63, 95%CI: 1.61-4.32), had higher family expenditure than income (OR=1.80, 95%CI: 1.17-2.78) and were in poor economic condition (OR=4.58, 95%CI: 2.48-8.47) had higher detection rate of depressive symptoms. Conclusion: The status of doing physical exercise, fish intake in diet, social activity participation, sleep quality or vision, and the prevalence of gastrointestinal ulcers and arthritis were associated with the detection rate of depressive symptoms in the elderly.

Age-related changes in microbial composition and function in cynomolgus macaques

Age can significantly affect human physiology and disease risk. Recent studies have shown that age may affect the composition and function of the gut microbiota, but the underlying mechanisms remain largely unknown. Non-human primates are an ideal model for uncovering how age shapes the gut microbiota, as their microbial composition is highly similar to that of humans and is not easily affected by confounding factors. Here, using the 16S rRNA and metagenomic sequencing methods, we characterized the microbial phenotypes of 16 female cynomolgus macaques from three age groups (young, adult and old). Our findings revealed significant differences in microbial composition among the three groups. With increased age, the relative abundances of Veillonellaceae, Coriobacteriaceae and Succinivibrionaceae were significantly increased, Ruminococcaceae and Rikenellaceae were significantly decreased at the family level. Functional enrichment showed that genes that differed among the three groups were mainly involved in arginine biosynthesis, purine metabolism and microbial polysaccharides metabolism. Moreover, CAZymes corresponding to polysaccharide degrading activities were also observed among the three groups. In conclusion, we characterized the composition and function of the gut microbiota at different ages, and our findings provide a new entry point for understanding the effects of age on the human body.

[Brain protection strategy and effectivity in pulmonary thromboendarterectomy]

Objective: To summarize the experience and effectivity of brain protection in 25 patients who suffered from chronic thromboembolic pulmonary hypertension (CTEPH) and received pulmonary thromboendarterectomy (PTE) under deep hypothermic circulatory arrest. Methods: Retrospective analysis of 25 PTE surgeries in our center from December 2016 to August 2018. All cases were completed underdeep hypothermic circulatory arrest. Standard brain protections were strictly executed, including: balanced and controlled extracorporeal circulation cooling, cerebral oxygen saturation (rSO(2)) monitoring, strictly control of circulatory arrest time, and etc. The neurological adverse events during the perioperative period were recorded and statistically analyzed, and the intelligence level and cognitive function of the patients were evaluated by MMSE scale and MoCA scale before surgery and discharge. Results: All the 25 patients successfully completed the surgery, and 1 patient (4%) died of postoperative infection. The mean pulmonary arterial pressure decreased from (52.9±16.7) mmHg before surgery to (23.6±8.1) mmHg immediately after surgery (t=10.01, P<0.01), and(20.7±7.9) mmHg at 3 months follow-up (t=10.73, P<0.01). Pulmonary vascular resistance decreased from 975.4 (788.6-1 292.8) dyn·s·cm(-5) to 376.1 (283.6-565.5) dyn·s·cm(-5) (Z=5.34, P<0.01). Neurological complications occurred in 3 patients during the perioperative period, including 2 patients with hypoxic encephalopathy, and 1 patient with cerebral hemorrhage. All 3 patients fully recovered before discharge. Univariate analysis showed that the duration of rSO(2)<40% and the maximum decrease rate of rSO(2) from baseline were significantly correlated with postoperative neurological damage. Multivariate analysis showed only time of rSO(2)<40% was significantly correlated with postoperative neurological damage. There was no significant difference in MMSE and MoCA score before and after surgery (P>0.05). Conclusions: Adequate brain protection measures are essential to reduce the neurological complications of PTE surgery. Real-time intraoperative monitoring of rSO(2) and strict control of circulatory arrest time can further reduce the occurrence of neurological damage.

Cerebral Venous Thrombosis: MR Black-Blood Thrombus Imaging with Enhanced Blood Signal Suppression

BACKGROUND AND PURPOSE

The residual blood flow artifact is a critical confounder for MR black-blood thrombus imaging of cerebral venous sinus thrombosis. This study aimed to conduct a validation of a new MR black-blood thrombus imaging technique with enhanced blood signal suppression.

MATERIALS AND METHODS

Twenty-six participants (13 volunteers and 13 patients) underwent conventional imaging methods followed by 2 randomized black-blood thrombus imaging scans, with a preoptimized delay alternating with nutation for tailored excitation (DANTE) preparation switched on and off, respectively. The signal intensity of residual blood, thrombus, brain parenchyma, normal lumen, and noise on black-blood thrombus images were measured. The thrombus volume, SNR of residual blood, and contrast-to-noise ratio for residual blood versus normal lumen, thrombus versus residual blood, and brain parenchyma versus normal lumen were compared between the 2 black-blood thrombus imaging techniques. Segmental diagnosis of venous sinus thrombosis was evaluated for each black-blood thrombus imaging technique using a combination of conventional imaging techniques as a reference.

RESULTS

In the volunteer group, the SNR of residual blood (11.3 ± 2.9 versus 54.0 ± 23.4, P < .001) and residual blood-to-normal lumen contrast-to-noise ratio (7.5 ± 3.4 versus 49.2 ± 23.3, P < .001) were significantly reduced using the DANTE preparation. In the patient group, the SNR of residual blood (16.4 ± 8.0 versus 75.0 ± 35.1, P = .002) and residual blood-to-normal lumen contrast-to-noise ratio (12.4 ± 7.8 versus 68.8 ± 35.4, P = .002) were also significantly lower on DANTE-prepared black-blood thrombus imaging. The new black-blood thrombus imaging technique provided higher thrombus-to-residual blood contrast-to-noise ratio, significantly lower thrombus volume, and substantially improved diagnostic specificity and agreement with conventional imaging methods.

CONCLUSIONS

DANTE-prepared black-blood thrombus imaging is a reliable MR imaging technique for diagnosing cerebral venous sinus thrombosis.

Mutation Analysis of Pre-mRNA Splicing Genes PRPF31, PRPF8, and SNRNP200 in Chinese Families with Autosomal Dominant Retinitis Pigmentosa

BACKGROUND

To screen variants in pre-mRNA Splicing genes in 95 Chinese autosomal dominant retinitis pigmentosa (adRP) families.

METHODS

Clinical examination and pedigree analysis were performed. Targeted exome sequencing (TES) and / or Sanger sequencing were performed to detect the variants in genes of Splicing factors and conduct intra-familiar segregation analysis with DNA available. In silico analysis was performed to predict pathogenicity of variants in protein level and in vitro splicing assays were performed to compare splicing variants with their corresponding wildtype about their splicing effect.

RESULTS

In this study, total nine different variants were identified in PRPF31, SNRNP200, and PRPF8 respectively, including six PRPF31 variants [five novel variants 322+1G>A, c.527+2T>G, c.590T>C(p.Leu197Pro), c.1035_1036insGC (p.Pro346Argfs X18), and c.1224dupG (p.Gln409AlafsX66) plus one reported variant c.1060C>T (p.Arg354X)], a recurrent PRPF8 variant c.6930G>T (p.Arg2310Ser), two SNRNP200 variants [one heterozygous and homozygous SNRNP200 recurrent variant c.3260G>A (p.Ser1087Leu), and a reported heterozygous c.2042G>A(p.Arg681His)]. In family 20009, incomplete penetrance was observed. A novel PRPF31 missense variant c.590T>C (p.Leu197Pro) was predicted to be pathogenic in protein level via in silico analysis and in vitro splicing assay demonstrated that two novel splicing PRPF31 variants c.322+1G>A and c.527+2T>G affect splicing compared with the wildtype.

CONCLUSIONS

In our studies, RP-causing variants of pre-mRNA Splicing genes (PRPF31, PRPF8 and SNRNP200) were identified in nine of the ninety-five adRP families respectively, which extend the spectra of RP variant and phenotype. And we provide the first example that SNRNP200-related RP can be caused by both heterozygous and homozygous variants of this gene.

Perturbed Microbial Ecology in Myasthenia Gravis: Evidence from the Gut Microbiome and Fecal Metabolome

Myasthenia gravis (MG) is a devastating acquired autoimmune disease. Emerging evidence indicates that the gut microbiome plays a key role in maintaining immune system homeostasis. This work reports that MG is characterized by decreased α-phylogenetic diversity, and significantly disturbed gut microbiome and fecal metabolome. The altered gut microbial composition is associated with fecal metabolome changes, with 38.75% of altered bacterial operational taxonomic units showing significant correlations with a range of metabolite biomarkers. Some microbes are particularly linked with MG severity. Moreover, a combination of microbial makers and their correlated metabolites enable discriminating MG from healthy controls (HCs) with 100% accuracy. To investigate whether disturbed gut mcirobiome might contribute to the onset of MG, germ-free (GF) mice are initially colonized with MG microbiota (MMb) or healthy microbiota (HMb), and then immunized in a classic mouse model of MG. The MMb mice demonstrate substantially impaired locomotion ability compared with the HMb mice. This effect could be reversed by cocolonizing GF mice with both MMb and HMb. The MMb mice also exhibit similar disturbances of fecal metabolic pathways as found in MG. Together these data demonstrate disturbances in microbiome composition and activity that are likely to be relevant to the pathogenesis of MG.

[Association of plasma albumin and hypersensitive C-reactive protein with 5-year all-cause mortality among Chinese older adults aged 65 and older from 8 longevity areas in China]

Objective: To investigate the relationship of plasma albumin and hypersensitive C-reactive protein (Hs-CRP) with 5-year all-cause mortality among Chinese older adults aged 65 and older. Method: Data was collected in 8 longevity areas of the Chinese Longitudinal Healthy Longevity Survey (CLHLS) study conducted by Chinese Center for Disease Control and Prevention and Peking University at baseline survey in 2012 and 2014, the participants enrolled in 2012 was followed-up in 2014 and 2017, the participants enrolled in 2014 was followed-up in 2017 only. Finally, 3 118 older adults aged 65 and older with complete information on albumin, Hs-CRP and body mass index (BMI) were included in this study. Plasma samples of older adults were collected for the detection of albumin and Hs-CRP at baseline survey. Survival status and follow-up time was recorded for all participants. All older adults were divided into 4 groups according to the levels of plasma albumin and Hs-CRP, and Cox proportional hazard models were constructed to assess their influence on the risk of all-cause mortality. Results: Among 3 118 older adults included, the prevalence of hypoalbuminemia was 10.1% (316/3 118), and was 22.8% (711/3 118) for elevated Hs-CRP. During 10 132 person-years of follow-up, 1 212 participants died. Participants with hypoalbuminemia had increased risk of all-cause mortality, with an hazard ratio (HR) and 95% confidential interval (CI) of 1.18 (1.01-1.38), compared to participants with normal plasma albuminemia; participants with elevated Hs-CRP had increased risk of all-cause mortality, with an HR (95%CI) of 1.18 (1.04-1.35), compared to participants with normal plasma Hs-CRP. Participants with normal plasma albumin and elevated Hs-CRP, with hypoalbuminemia and normal Hs-CRP, with hypoalbuminemia and elevated Hs-CRP also had increased risk of all-cause mortality when compared to those with normal plasma albumin and normal Hs-CRP, the HR (95%CI) were 1.16 (1.01-1.34), 1.11 (0.91-1.37) and 1.43 (1.11-1.83), respectively. Conclusion: Hypoalbuminemia and elevated Hs-CRP were responsible for increased risk of 5-year all-cause mortality among Chinese older adults from 8 longevity areas.

A proposal for standardized magnetic resonance imaging (MRI) descriptors of abnormally invasive placenta (AIP) - From the International Society for AIP

Abnormally invasive placenta (AIP) is used to describe a placenta that does not separate naturally after delivery and cannot be extirpated without causing abnormally high blood loss. Recently, the use of a standardized terminology for descriptors of AIP signs seen on ultrasound has been prosed but to date no such unified descriptors have been developed for magnetic resonance imaging (MRI). The purpose of this paper is to propose a unified terminology based on a consensus opinion from the members of the International Society for AIP (IS-AIP) that include obstetricians, gynecologists, radiologists, pathologists, anesthesiologists and basic science researchers. We assume that using these standardized MRI descriptors for AIP will be useful for clinical use, education, teaching and future research projects, thus assumably improving care of patients with this condition. In addition, using a uniform terminology for AIP should become the first step of a standardized MRI report.

Immunogenicity and safety of an accelerated hepatitis E vaccination schedule in healthy adults: a randomized, controlled, open-label, phase IV trial

OBJECTIVES

This study aimed to evaluate the immunogenicity and safety of a hepatitis E (HE) vaccine using an accelerated vaccination schedule (vaccine doses at 0, 7 and 21 days).

METHODS

A total of 126 participants aged ≥18 years were randomly assigned to receive the hepatitis E virus vaccine in either the accelerated group (0, 7 and 21 days) or the routine group (0, 1 and 6 months). Serology samples were obtained at 0, 21, 28 and 51 days, and 7 months in the accelerated group, or 0, 1, 2 and 7 months in the routine group after the first vaccine injection. Adverse events (AEs) reported during the whole study were analysed.

RESULTS

A total of 126 participants were randomized, 63 for each group. Sixty-two participants in the accelerated group and 63 in the routine group received at least one dose of vaccine; 57 and 63 participants received all three doses and were included in per-protocol set, respectively. In the per-protocol population, at 1 month after the last dose (accelerated group at 51 days versus routine group at 7 months), the seropositive rates were both 100% (57/57 and 63/63, respectively), and the geometric mean concentrations (GMCs) were 8.51 WHO units/mL (95% CI 6.73-10.76) in the accelerated group and 9.67 WHO units/mL (95% CI 7.67-12.20) in the routine group. The ratio of the accelerated group GMC to the routine group GMC was 0.88 (95% CI 0.61-2.17, lower limit of 95% CI > 0.5), indicating that the accelerated vaccination schedule was non-inferior to the routine one. The overall incidence rates of solicited AEs in the accelerated and routine groups were 32.26% (20/62) and 30.16% (19/63), respectively (p 0.800). Most AEs were moderate.

CONCLUSIONS

An accelerated schedule is safe and provides protective antibodies in a shorter time compared with the routine schedule. The accelerated schedule should be recommended to adults who are travelling on short notice to an HE-endemic area or during an HE outbreak (Clinical Trial Registration. NCT03168412).

Alterations Of Glycerophospholipid And Fatty Acyl Metabolism In Multiple Brain Regions Of Schizophrenia Microbiota Recipient Mice

BACKGROUND

Schizophrenia is a debilitating psychiatric disorder characterized by molecular and anatomical abnormalities of multiple brain regions. Our recent study showed that dysbiosis of the gut microbiota contributes to the onset of schizophrenia-relevant behaviors, but the underlying mechanisms remain largely unknown.

PURPOSE

This study aimed to investigate how gut microbiota shapes metabolic signatures in multiple brain regions of schizophrenia microbiota recipient mice.

METHODS

Gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS) were used to compare the metabolic signatures in the cortex, cerebellum and striatum of schizophrenia microbiota and healthy microbiota recipient mice. Enrichment analysis was further conducted to uncover the crucial metabolic pathways related to schizophrenia-relevant behaviors.

RESULTS

We found that the metabolic phenotypes of these three regions were substantially different in schizophrenia microbiota recipient mice from those in healthy microbiota recipient mice. In total, we identified 499 differential metabolites that could discriminate the two groups in the three brain regions. These differential metabolites were mainly involved in glycerophospholipid and fatty acyl metabolism. Moreover, we found four of fatty acyl metabolites that were consistently altered in the three brain regions.

CONCLUSION

Taken together, our study suggests that alterations of glycerophospholipid and fatty acyl metabolism are implicated in the onset of schizophrenia-relevant behaviors, which may provide a new understanding of the etiology of schizophrenia.