Tag: statistics

Sci Rep. 2021 Mar 31;11(1):7246. doi: 10.1038/s41598-021-86431-8.

ABSTRACT

This study examined temporal trend, seasonality, and geographical variations of legionellosis incidence and mortality in Japan. This nationwide observational study used the Japanese Vital Statistics and Infectious Diseases Weekly Report (1999-2017) data to calculate legionellosis crude and age-adjusted incidence and mortality rates per 100,000 population by age and sex. Incidence was compared among the 4 seasons and regional incidence among 47 prefectures. Of 13,613 (11,194 men) people with legionellosis in Japan, 725 (569 men) were fatal. Increasing incidence trend occurred from 0.0004 (1999) to 1.37 (2017) per 100,000 population. People aged ≥ 70 years accounted for 43.1% overall; men’s age-adjusted incidence rate was consistently approximately five times higher than for women. Significantly higher incidence occurred in summer than in winter (p = 0.013). Geographically, highest incidence (≥ 2.0 per 100,000 population) occurred in Hokuriku District, with increasing trends in Hokkaido and middle-part of Japan. Estimated fatality rates decreased consistently at 5.9% (95% confidence interval: – 8.1, – 3.5) annually, from 1999 to 2017, with no trend change point. Increasing legionellosis incidence occurred in Japan during 1999-2017, with declining estimated fatality rates. In this aging society and warming world, disease clinical burden may further deteriorate in future due to increasing incidence trends.

PMID:33790327 | DOI:10.1038/s41598-021-86431-8

J Neurosci. 2021 Mar 22:JN-RM-1993-20. doi: 10.1523/JNEUROSCI.1993-20.2021. Online ahead of print.

ABSTRACT

A visual object is characterized by multiple visual features, including its identity, position and size. Despite the usefulness of identity and nonidentity features in vision and their joint coding throughout the primate ventral visual processing pathway, they have so far been studied relatively independently. Here in both female and male human participants, the coding of identity and nonidentity features was examined together across the human ventral visual pathway. The nonidentity features tested included two Euclidean features (position and size) and two non-Euclidean features (image statistics and spatial frequency content of an image). Overall, identity representation increased and nonidentity feature representation decreased along the ventral visual pathway, with identity outweighing the non-Euclidean but not the Euclidean features at higher levels of visual processing. In 14 convolutional neural networks (CNNs) pretrained for object categorization with varying architecture, depth, and with/without recurrent processing, nonidentity feature representation showed an initial large increase from early to mid-stage of processing, followed by a decrease at later stages of processing, different from brain responses. Additionally, from lower to higher levels of visual processing, position became more underrepresented and image statistics and SF became more overrepresented compared to identity in CNNs than in the human brain. Similar results were obtained in a CNN trained with stylized images that emphasized shape representations. Together, by measuring the coding strength of object identity and nonidentity features together, our approach provided a new tool for characterizing feature coding in the human brain and the correspondence between the brain and CNNs.SIGNIFICANCE STATEMENTThis study examined the coding strength of object identity and four types of nonidentity features along the human ventral visual processing pathway and compared brain responses with those of 14 CNNs pretrained to perform object categorization. Overall, identity representation increased and nonidentity feature representation decreased along the ventral visual pathway, with some notable differences among the different nonidentity features. CNNs differed from the brain in a number of aspects in their representations of identity and nonidentity features over the course of visual processing. Our approach provides a new tool for characterizing feature coding in the human brain and the correspondence between the brain and CNNs.

PMID:33789916 | DOI:10.1523/JNEUROSCI.1993-20.2021

J Chest Surg. 2021 Apr 5;54(2):88-98. doi: 10.5090/jcs.20.102.

ABSTRACT

BACKGROUND: This study aimed to develop a new risk prediction model for operative mortality in a Korean cohort undergoing heart valve surgery using the Korea Heart Valve Surgery Registry (KHVSR) database.

METHODS: We analyzed data from 4,742 patients registered in the KHVSR who underwent heart valve surgery at 9 institutions between 2017 and 2018. A risk prediction model was developed for operative mortality, defined as death within 30 days after surgery or during the same hospitalization. A statistical model was generated with a scoring system by multiple logistic regression analyses. The performance of the model was evaluated by its discrimination and calibration abilities.

RESULTS: Operative mortality occurred in 142 patients. The final regression models identified 13 risk variables. The risk prediction model showed good discrimination, with a c-statistic of 0.805 and calibration with Hosmer-Lemeshow goodness-of-fit p-value of 0.630. The risk scores ranged from -1 to 15, and were associated with an increase in predicted mortality. The predicted mortality across the risk scores ranged from 0.3% to 80.6%.

CONCLUSION: This risk prediction model using a scoring system specific to heart valve surgery was developed from the KHVSR database. The risk prediction model showed that operative mortality could be predicted well in a Korean cohort.

PMID:33790059 | DOI:10.5090/jcs.20.102

Nat Commun. 2021 Mar 31;12(1):1990. doi: 10.1038/s41467-021-22156-6.

ABSTRACT

A crucial phase in the infection process, which remains poorly understood, is the localization of suitable host cells by bacteria. It is often assumed that chemotaxis plays a key role during this phase. Here, we report a quantitative study on how Salmonella Typhimurium search for T84 human colonic epithelial cells. Combining time-lapse microscopy and mathematical modeling, we show that bacteria can be described as chiral active particles with strong active speed fluctuations, which are of biological, as opposed to thermal, origin. We observe that there exists a giant range of inter-individual variability of the bacterial exploring capacity. Furthermore, we find Salmonella Typhimurium does not exhibit biased motion towards the cells and show that the search time statistics is consistent with a random search strategy. Our results indicate that in vitro localization of host cells, and also cell infection, are random processes, not involving chemotaxis, that strongly depend on bacterial motility parameters.

PMID:33790272 | DOI:10.1038/s41467-021-22156-6

Sci Adv. 2021 Mar 31;7(14):eabe7377. doi: 10.1126/sciadv.abe7377. Print 2021 Mar.

ABSTRACT

Whether the upper limb branch of Paleozoic “biramous” arthropods, including trilobites, served a respiratory function has been much debated. Here, new imaging of the trilobite Triarthrus eatoni shows that dumbbell-shaped filaments in the upper limb branch are morphologically comparable with gill structures in crustaceans that aerate the hemolymph. In Olenoides serratus, the upper limb’s partial articulation to the body via an extended arthrodial membrane is morphologically comparable to the junction of the respiratory book gill of Limulus and differentiates it from the typically robust exopod junction in Chelicerata or Crustacea. Apparently limited mechanical rotation of the upper branch may have protected the respiratory structures. Partial attachment of the upper branch to the body wall may represent an intermediate state in the evolution of limb branch fusion between dorsal attachment to the body wall, as in Radiodonta, and ventral fusion to the limb base, as in extant Euarthropoda.

PMID:33789898 | DOI:10.1126/sciadv.abe7377

Sci Adv. 2021 Mar 31;7(14):eabe9765. doi: 10.1126/sciadv.abe9765. Print 2021 Mar.

ABSTRACT

Advances in spectroscopy have the potential to improve our understanding of agricultural processes and associated trace gas emissions. We implement field-deployed, open-path dual-comb spectroscopy (DCS) for precise multispecies emissions estimation from livestock. With broad atmospheric dual-comb spectra, we interrogate upwind and downwind paths from pens containing approximately 300 head of cattle, providing time-resolved concentration enhancements and fluxes of CH₄, NH₃, CO₂, and H₂O. The methane fluxes determined from DCS data and fluxes obtained with a colocated closed-path cavity ring-down spectroscopy gas analyzer agree to within 6%. The NH₃ concentration retrievals have sensitivity of 10 parts per billion and yield corresponding NH3 fluxes with a statistical precision of 8% and low systematic uncertainty. Open-path DCS offers accurate multispecies agricultural gas flux quantification without external calibration and is easily extended to larger agricultural systems where point-sampling-based approaches are insufficient, presenting opportunities for field-scale biogeochemical studies and ecological monitoring.

PMID:33789900 | DOI:10.1126/sciadv.abe9765

BMJ Open Gastroenterol. 2021 Mar;8(1):e000501. doi: 10.1136/bmjgast-2020-000501.

ABSTRACT

OBJECTIVE: Severe acute pancreatitis (SAP) is associated with high mortality (15%-30%). Current guidelines recommend these patients are best managed in a multidisciplinary team setting. This study reports experience in the management of SAP within the UK’s first reported hub-and-spoke pancreatitis network.

DESIGN: All patients with SAP referred to the remote care pancreatitis network between 2015 and 2017 were prospectively entered onto a database by a dedicated pancreatitis specialist nurse. Baseline characteristics, aetiology, intensive care unit (ICU) stay, interventions, complications, mortality and follow-up were analysed.

RESULTS: 285 patients admitted with SAP to secondary care hospitals during the study period were discussed with the dedicated pancreatitis specialist nurse and referred to the regional service. 83/285 patients (29%; 37 male) were transferred to the specialist centre mainly for drainage of infected pancreatic fluid collections (PFC) in 95% (n=79) of patients. Among the patients transferred; 29 (35%) patients developed multiorgan failure with an inpatient mortality of 14% (n=12/83). The median follow-up was 18.2 months (IQR=11.25-35.51). Multivariate analysis showed that transferred patients had statistically significant longer overall hospital stay (p<0.001) but less ICU stay (p<0.012).

CONCLUSION: This hub-and-spoke model facilitates the management of the majority of patients with SAP in secondary care setting. 29% warranted transfer to our tertiary centre, predominantly for endoscopic drainage of PFCs. An evidence-based approach with a low threshold for transfer to tertiary care centre can result in lower mortality for SAP and fewer days in ICU.

PMID:33789915 | DOI:10.1136/bmjgast-2020-000501

BMJ. 2021 Mar 31;372:n693. doi: 10.1136/bmj.n693.

ABSTRACT

OBJECTIVE: To quantify rates of organ specific dysfunction in individuals with covid-19 after discharge from hospital compared with a matched control group from the general population.

DESIGN: Retrospective cohort study.

SETTING: NHS hospitals in England.

PARTICIPANTS: 47 780 individuals (mean age 65, 55% men) in hospital with covid-19 and discharged alive by 31 August 2020, exactly matched to controls from a pool of about 50 million people in England for personal and clinical characteristics from 10 years of electronic health records.

MAIN OUTCOME MEASURES: Rates of hospital readmission (or any admission for controls), all cause mortality, and diagnoses of respiratory, cardiovascular, metabolic, kidney, and liver diseases until 30 September 2020. Variations in rate ratios by age, sex, and ethnicity.

RESULTS: Over a mean follow-up of 140 days, nearly a third of individuals who were discharged from hospital after acute covid-19 were readmitted (14 060 of 47 780) and more than 1 in 10 (5875) died after discharge, with these events occurring at rates four and eight times greater, respectively, than in the matched control group. Rates of respiratory disease (P<0.001), diabetes (P<0.001), and cardiovascular disease (P<0.001) were also significantly raised in patients with covid-19, with 770 (95% confidence interval 758 to 783), 127 (122 to 132), and 126 (121 to 131) diagnoses per 1000 person years, respectively. Rate ratios were greater for individuals aged less than 70 than for those aged 70 or older, and in ethnic minority groups compared with the white population, with the largest differences seen for respiratory disease (10.5 (95% confidence interval 9.7 to 11.4) for age less than 70 years v 4.6 (4.3 to 4.8) for age ≥70, and 11.4 (9.8 to 13.3) for non-white v 5.2 (5.0 to 5.5) for white individuals).

CONCLUSIONS: Individuals discharged from hospital after covid-19 had increased rates of multiorgan dysfunction compared with the expected risk in the general population. The increase in risk was not confined to the elderly and was not uniform across ethnicities. The diagnosis, treatment, and prevention of post-covid syndrome requires integrated rather than organ or disease specific approaches, and urgent research is needed to establish the risk factors.

PMID:33789877 | DOI:10.1136/bmj.n693

Zhonghua Yi Xue Za Zhi. 2021 Mar 30;101(12):851-855. doi: 10.3760/cma.j.cn112137-20210111-00086.

ABSTRACT

Objective: To investigate the efficacy and safety of prophylactic intravenous (IV) administration of tranexamic acid (TXA) in abdominal aorta balloon-assisted pelvic tumor surgery. Methods: The data of patients who underwent abdominal aorta balloon-assisted pelvic tumor surgery in Peking University People’s Hospital from January 1, 2015 to December 31, 2019 were retrospectively collected. According to whether receiving the prophylactic use of TXA, the patients were divided into two groups: TXA group and control group. After propensity score matching based on age, gender and surgeon, 51 patients in TXA group and 51 patients in control group were allocated. The baseline, intraoperative and postoperative clinical data of the two groups were compared to explore the efficacy and safety of TXA. Results: A total of 525 cases undergoing abdominal aorta balloon-assisted pelvic surgery were enrolled from 2015 to 2019, of which 51 cases received prophylactic use of TXA, with a utilization rate of 9.7%. There were no significant differences in age [(40.7±15.1) years vs (38.2±14.5) years, P=0.393], gender (male: 51.0% vs 49.0%, P=0.843), body weight, body mass index (BMI), complications, American Society of Anesthesiologists (ASA) classification, hemoglobin, hemocrit (Hct), platelet, coagulation function-related indexes and tumor pathological types between the two groups (all P>0.05). Likewise, there were no significant differences in operation time, anesthesia time, cumulative time of balloon occlusion, intraoperative blood loss, intravenous fluid volume and blood transfusion volume between the two groups (all P>0.05). Additionally, there were no significant differences in postoperative ICU admission rate and length of hospital stay between the two groups (all P>0.05), and no venous thromboembolism (VTE) or death was reported. Compared with the control group, the rate of blood transfusion at 24 hours after operation in the TXA group was lower (41.2% vs 70.6%, P=0.003). The level of fibrinogen degradation products was lower [10.4 (6.1, 22.6) mg/L vs 13.2 (7.0, 24.7) mg/L], but the difference was not statistically significant (P=0.326). Conclusions: Prophylactic IV use of TXA does not reduce intraoperative bleeding in abdominal aorta balloon-assisted pelvic tumor surgery, but can decrease the rate of postoperative blood transfusion. No increased risk of postoperative TXA-related VTE was observed.

PMID:33789366 | DOI:10.3760/cma.j.cn112137-20210111-00086

Genetics. 2021 Mar 31;217(3):iyaa046. doi: 10.1093/genetics/iyaa046.

ABSTRACT

We propose an extended Gaussian mixture model for the distribution of causal effects of common single nucleotide polymorphisms (SNPs) for human complex phenotypes that depends on linkage disequilibrium (LD) and heterozygosity (H), while also allowing for independent components for small and large effects. Using a precise methodology showing how genome-wide association studies (GWASs) summary statistics (z-scores) arise through LD with underlying causal SNPs, we applied the model to GWAS of multiple human phenotypes. Our findings indicated that causal effects are distributed with dependence on total LD and H, whereby SNPs with lower total LD and H are more likely to be causal with larger effects; this dependence is consistent with models of the influence of negative pressure from natural selection. Compared with the basic Gaussian mixture model it is built on, the extended model-primarily through quantification of selection pressure-reproduces with greater accuracy the empirical distributions of z-scores, thus providing better estimates of genetic quantities, such as polygenicity and heritability, that arise from the distribution of causal effects.

PMID:33789345 | DOI:10.1093/genetics/iyaa046