bluuebunny/crossref_metadata_2025_split huggingface dataset:
Association of comorbidities with COVID-19 infection rate and severity: nationwide cohort study with propensity score matching
Authors: Kim Jiyong , Park Seong Hun , Kim Jong Moon 
Published: September 2021

ABSTRACTObjectiveTo describe the association of comorbidities with coronavirus infection-19 (COVID-19) infection rates and severity of infection through Korean nationwide medical system.DesignNationwide population-based retrospective cohort study.SettingKorean national health insurance claims database between January 1, 2020, and May 30, 2020.ParticipantsPatients with positive COVID-19 test and 12 folded controls matched by age, sex and region.Main Outcomes MeasuresOutcomes were confirmation of the comorbidities affecting the infection rate and the severity of COVID-19. Patients and outcomes were propensity score matching of factors which may affect COVID-19 infection rate and severity was performed. COVID-19 infections were confirmed through laboratory testing. Severe infection was defined as those who underwent tracheostomy, continuous renal replacement therapy, intensive care unit admission, ventilator use, cardiopulmonary resuscitation, or died.ResultsA total of 8070 individuals with positive covid-19 test and 12015 controls were identified. In people aged 60 or older, in those insured with Medicaid, and in the disabled, the proportion corresponding to the severe group of patients showed a tendency to increase. The infection rate of COVID-19 was highest in pulmonary disease (adjusted odds ratio 1.88, 95% confidence interval 1.70 to 2.03), and hyperlipidemia (0.73, 0.67 to 0.80) had a lower infection rate. Disease severity was highest in kidney disease (5.59, 2.48 to 12.63), and lower in hyperlipidemia (0.78, 0.60 to 1.00).ConclusionsThere is less bias as the government pays for all tests and treatments related to COVID-19 included in the data used in this study. Using propensity matching to reduce statistical bias, we found that most comorbidities increased the infection rate and severity of COVID-19, whereas hyperlipidemia reduced the rate and severity of infection. These results can be utilized to effectively manage COVID-19 infections.
Downsizing food: A systematic review and meta-analysis examining the effect of reducing served food portion sizes on daily energy intake and body weight
Authors: Robinson Eric , McFarland-Lesser India , Patel Zina , Jones Andrew 
Published: September 2021

AbstractBackgroundPortion sizes of many foods have increased over time and reducing food portion sizes has been proposed as a public health strategy to reduce obesity. However, the extent to which reducing food portion sizes affects daily energy intake and body weight is unclear.ObjectiveTo systematically review and meta-analyse experimental studies that have examined the effect that serving smaller vs. larger portion sizes has on total daily energy intake.DesignWe used systematic review methodology to search identify eligible articles that used an experimental design to manipulate portion size served to human participants and measured energy intake for a minimum of one day. Multi-level meta-analysis was used to used to pool effects of portion size on daily energy intake.ResultsFourteen eligible studies were included and 85 effects were included in the primary meta-analysis. There was a moderate-to-large reduction in daily energy intake when comparing smaller vs. larger portions (SMD = -.709 [95% CI: -.956 to -.461], p < .001, I2 = 80.6%) and evidence of a dose dependent response. Larger reductions to portion size and reducing portion sizes of multiple meals per day both resulted in larger decreases in daily energy intake. There was also evidence of a curvilinear relationship between portion size and daily energy intake, whereby reductions to daily energy intake were markedly smaller when reducing portion size from very large portions. In a subset of studies that measured body weight (n=5), being served smaller portions was associated with less weight gain than larger portions (SMD = .536 ([95% CI: .268 to .803], p < .001, I2 = 47.0%).ConclusionsSmaller food portion sizes substantially decrease daily energy intake and there is evidence that over time this results in lower body weight. Reducing food portion sizes may be an effective population level strategy to reduce obesity.
COVID-19 mortality risk correlates inversely with vitamin D3 status, and a mortality rate close to zero could theoretically be achieved at 50 ng/ml 25(OH)D3: Results of a systematic review and meta-analysis
Authors: Borsche Lorenz , Glauner Bernd , von Mendel Julian 
Published: September 2021

AbstractBackgroundMuch research shows that blood calcidiol (25(OH)D3) levels correlate strongly with SARS-CoV-2 infection severity. There is open discussion regarding whether low D3 is caused by the infection or if deficiency negatively affects immune defense. The aim of this study was to collect further evidence on this topic.MethodsSystematic literature search was performed to identify retrospective cohort as well as clinical studies on COVID-19 mortality rates versus D3 blood levels. Mortality rates from clinical studies were corrected for age, sex and diabetes. Data were analyzed using correlation and linear regression.ResultsOne population study and seven clinical studies were identified, which reported D3 blood levels pre-infection or on the day of hospital admission. They independently showed a negative Pearson correlation of D3 levels and mortality risk (r(17)=-.4154, p=.0770/r(13)=-.4886, p=.0646). For the combined data, median (IQR) D3 levels were 23.2 ng/ml (17.4 – 26.8), and a significant Pearson correlation was observed (r(32)=-.3989, p=.0194). Regression suggested a theoretical point of zero mortality at approximately 50 ng/ml D3.ConclusionsThe two datasets provide strong evidence that low D3 is a predictor rather than a side effect of the infection. Despite ongoing vaccinations, we recommend raising serum 25(OH)D levels to above 50 ng/ml to prevent or mitigate new outbreaks due to escape mutations or decreasing antibody activity.Trial registrationNot applicable.
Label-free Raman microspectroscopy for identifying virocells
Authors: Monsees Indra , Turzynski Victoria , Esser Sarah P. , Soares André , Timmermann Lara I. , Weidenbach Katrin , Banas Jarno , Kloster Michael , Beszteri Bánk , Schmitz Ruth A. , Probst Alexander J. 
Published: September 2021

AbstractRaman microspectroscopy has been thoroughly used to assess growth dynamics and heterogeneity of prokaryotic cells. Yet, little is known about how the chemistry of individual cells changes during infection with lytic viruses, resulting in so-called virocells. Here, we investigate biochemical changes of bacterial and archaeal cells of three different species in laboratory cultures before and after addition of their respective viruses using single-cell Raman microspectroscopy. By applying multivariate statistics, we identified significant differences in the spectra of single cells and cells after addition of lytic phage (phi6) for Pseudomonas syringae. A general ratio of wavenumbers that contributed the greatest differences in the recorded spectra was defined as an indicator for virocells. Based on reference spectra, this difference is likely attributable to an increase in nucleic acid vs. protein ratio of virocells. This method proved also successful for identification of Bacillus subtilis cells infected with phi29 displaying a decrease in respective ratio but failed for archaeal virocells (Methanosarcina mazei with Methanosarcina Spherical Virus) due to autofluorescence. Multivariate and univariate analyses suggest that Raman spectral data of infected cells can also be used to explore the complex biology behind viral infections of bacteria. Using this method, we confirmed the previously described two-stage infection of P. syringae’s phi6 and that infection of B. subtilis by phi29 results in a stress response within single cells. We conclude that Raman microspectroscopy is a promising tool for chemical identification of Gram-positive and Gram-negative virocells undergoing infection with lytic DNA or RNA viruses.ImportanceViruses are highly diverse biological entities shaping many ecosystems across Earth. Yet, understanding the infection of individual microbial cells and the related biochemical changes remains limited. Using Raman microspectroscopy in conjunction with univariate and unsupervised machine learning approaches, we established a marker for identification of infected Gram-positive and Gram-negative bacteria. This non-destructive, label-free analytical method at single-cell resolution paves the way for future studies geared towards analyzing complex biological changes of virus-infected cells in pure culture and natural ecosystems.
Variable freshwater influences on the abundance of Vibrio vulnificus in a tropical urban estuary
Authors: Nigro Olivia D. , James-Davis La’Toya I. , De Carlo Eric Heinen , Li Yuan-Hui , Steward Grieg F. 
Published: September 2021

ABSTRACTTo better understand the controls on the opportunistic human pathogen Vibrio vulnificus in warm tropical waters, we conducted a year-long investigation in the Ala Wai Canal, a channelized estuary in Honolulu, HI. The abundance of V. vulnificus as determined by qPCR of the hemolysin gene (vvhA), varied spatially and temporally nearly four orders of magnitude (≤ 3 to 14,000 mL-1). Unlike in temperate and subtropical systems, temperatures were persistently warm (19–31°C) and explained little of the variability in V. vulnificus abundance. Salinity (1–36 ppt) had a significant, but non-linear, relationship with V. vulnificus abundance with highest vvhA concentrations (> 2,500 mL-1) observed only at salinities from 7 to 22 ppt. V. vulnificus abundances were lower on average in the summer dry season when waters were warmer but more saline. Highest canal-wide average abundances were observed during a time of modest rainfall when moderate salinities and elevated concentrations of reduced nitrogen species and silica suggested a groundwater influence. Distinguishing the abundances of two genotypes of V. vulnificus (C-type and E-type) suggest that C-type strains, which are responsible for most human infections, were usually less abundant (25% on average), but their relative contribution was greater at higher salinities, suggesting a broader salinity tolerance. Generalized regression models suggested up to 67% of sample-to-sample variation in log-transformed V. vulnificus abundance was explained (n = 202) using the measured environmental variables, and up to 97% of the monthly variation in canal-wide average concentrations (n = 13) was explained with the best subset of four variables.IMPORTANCEOur data illustrate that, in the absence of strong seasonal variation in water temperature in the tropics, variation in salinity driven by rainfall becomes a primary controlling variable on V. vulnificus abundance. There is thus a tendency for a rainfall-driven seasonal cycle in V. vulnificus abundance that is inverted from the temperature-driven seasonal cycle at higher latitudes. However, stochasticity in rainfall and its non-linear, indirect effects on V. vulnificus concentration means that high abundances can occur at any location in the canal at any time of year, making it challenging to predict concentrations of this pathogen at high temporal or spatial resolution. Much of the variability in canal-wide average concentrations, on the other hand, was explained by a few variables that reflect the magnitude of freshwater input to the system, suggesting that relative risk of exposure to this pathogen could be predicted for the system as a whole.
Social contacts and transmission of COVID-19 in British Columbia, Canada
Authors: Ringa Notice , Otterstatter Michael C. , Iyaniwura Sarafa A. , Irvine Mike A. , Adu Prince , Janjua Naveed Z. , David Samara , Spencer Michelle 
Published: September 2021

AbstractPurposeClose-contact rates are thought to be a significant driving force behind the dynamics of transmission for many infectious respiratory diseases. Efforts to control such infections typically focus on the practice of strict contact-avoidance measures. Yet, contact rates and their relation to transmission, and the impact of control measures, are seldom quantified. Here, we quantify the response of contact rates, transmission and new cases of COVID-19 to public health contact-restriction orders, and the associations among these three variables, in the Canadian province of British Columbia (BC) and within its two most densely populated regional health authorities: Fraser Health Authority (FHA) and Vancouver Coastal Health Authority (VCHA).MethodsWe obtained time series for self-reported close-contact rates from the BC Mix COVID-19 Survey, new reported cases of COVID-19 from the BC Center for Disease Control, and transmission rates based on dynamic model fits to reported cases. Our study period was from September 13, 2020 to February 19, 2021, during which three public health contact-restriction orders were introduced (October 26, November 7 and November 19, 2020). We used segmented linear regression to quantify impacts of public health orders, Pearson correlation to assess the instantaneous relation between contact rates and transmission, and vector autoregressive modeling to study the lagged relations among the three variables.ResultsOverall, declines in contact rates and transmission occurred concurrently with the announcement of public health orders, whereas declines in new cases showed a reporting delay of roughly two weeks. The impact of the first public health order (October 26, 2020) on contact rates and transmission was more pronounced than that of the other two health orders. Contact rates and transmission on the same day were strongly correlated (correlation coefficients = 0.64, 0.53 and 0.34 for BC, FHA, and VCHA, respectively). Moreover, contact rates were a significant time-series driver of COVID-19 and explained roughly 30% and 18% of the variation in new cases and transmission, respectively. Interestingly, increases in transmission and new cases were followed by reduced rates of contact: overall, average daily cases explained about 10% of the variation in provincial contact rates.ConclusionWe show that close-contact rates were a significant driver of transmission of COVID-19 in British Columbia, Canada and that they varied in response to public health orders. Our results also suggest a possible feedback, by which contact rates respond to recent changes in reported cases. Our findings help to explain and validate the commonly assumed, but rarely measured, response of close contact rates to public health guidelines and their impact on the dynamics of infectious diseases.
Behavioral Markers for Deficits in Speed of Processing in Cerebrovascular Disease
Authors: Chen Ying , Sunderland Kelly M , Khoo Yuelee , McLaughlin Paula M. , Kwan Donna , Fraser Julia , Ramirez Joel , Binns Malcolm A. , Arnott Stephen R. , Beaton Derek , Brien Donald C. , Casaubon Leanne K. , Coe Brian C. , Cornish Benjamin , Dowlatshahi Dariush , Hassan Ayman , Levine Brian , Lou Wendy , Mandzia Jennifer , McIlroy William , Montero-Odasso Manuel , Van Ooteghem Karen , Orange Joseph B. , Peltsch Alicia J. , Pieruccini-Faria Frederico , Raamana Pradeep Reddy , Roberts Angela C. , Sahlas Demetrios , Saposnik Gustavo , Strother Stephen C. , Swartz Richard H. , Troyer Angela K. ,   the ONDRI Investigators, Munoz Douglas P. 
Published: September 2021

AbstractObjectiveTo assess overlap and uniqueness of established behavioral markers of speed of processing for different aspects of visual information within a cerebrovascular disease cohort, and to examine the link between these speed of processing markers and functional behavior, specifically walking.MethodsA cohort of 161 participants with cerebrovascular disease recruited to the Ontario Neurodegenerative Disease Research Initiative (ONDRI) were examined with three types of assessments: neuropsychology, saccadic eye movement and gait. Principal component analysis (PCA) and canonical correlation analysis (CCA) were performed on select variables from these assessments to reveal commonalities and discrepancies among the measures.ResultsPCA analysis revealed different variable patterns between neuropsychology and saccade assessments, with the first component characterized primarily by neuropsychology, and the second and third components more influenced by the saccade assessments. CCA analysis did not reveal association between different types of assessments with the exception of a modest, but significant, positive association between speed of processing measures from the neuropsychological assessments and gait speed.DiscussionNeuropsychological tests and the pro-saccade task can be used for assessment of speed of processing for two major features of visual information, visual perception vs. spatial location. Despite a general lack of association between different types of assessments, combining gait speed as an important contributor to the models reinforces the idea of the link between speed of processing and complex function such as walking, and provides support for the importance of attending to the potential consequences of changes in speed of processing after neurologic injury.
COVID-19 Vaccine Breakthrough Infections in Veterans Health Administration
Authors: Sharma Aditya , Oda Gina , Holodniy Mark 
Published: September 2021

BackgroundVaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been accompanied by rising concern of vaccine breakthrough due to SARS-CoV-2 variants, waning protection over time, differential vaccine effectiveness, and regional resurgence of Coronavirus 2019 (COVID-19). Characterizing the frequency and drivers of vaccine breakthrough is necessary to inform COVID-19 control efforts.MethodsWe performed a retrospective cohort study of vaccine breakthrough infections in fully vaccinated persons in Veterans Health Administration. We applied Cox proportional hazard models to estimate cumulative incidence, assess differences in outcomes by vaccine, and identify associations with individual characteristics as well as time-dependent geographic variation in COVID-19 incidence, proportion of delta variant, and vaccine coverage.ResultsAmong 3,032,561 fully vaccinated persons, documented SARS-CoV-2 infection occurred in 11,197 (0.37%) and COVID-19 hospitalization occurred in 2,080 (0.07%). Compared to Ad26.COV2.S, BNT162b2 and mRNA-1273 had lower occurrence of documented SARS-CoV-2 infection (aHR 0.54, 95% confidence interval (CI) 0.51-0.58; aHR 0.36; 95% CI 0.33-0.38; respectively) and COVID-19 hospitalization (aHR 0.56, 95% CI 0.47-0.66; aHR 0.30; 0.25-0.35; respectively). Documented SARS-CoV-2 infection and COVID-19 hospitalization were associated with younger age, Hispanic or Latino ethnicity, number of comorbidities, and previous SARS-CoV-2 infection. Regional proportion of delta variant and county-level COVID-19 incidence were predictors of vaccine breakthrough events; county-level vaccine coverage was inversely associated.ConclusionsVaccine breakthrough was rare among fully vaccinated persons. mRNA-1273 and BNT162b2 were more protective against documented SARS-CoV-2 infection and COVID-19 hospitalization compared to Ad26.COV2.S. Efforts to limit COVID-19 transmission and bolster vaccine coverage would also curtail vaccine breakthrough.
Relationship between support for workers with illness and work functioning impairment in Japan during the COVID-19 pandemic
Authors: Igarashi Yu , Tateishi Seiichiro , Harada Arisa , Hino Ayako , Tsuji Mayumi , Ogami Akira , Mori Koji , Matsugaki Ryutaro , Fujino Yoshihisa ,   for the CORoNaWork project
Published: September 2021

AbstractObjectiveThis study examined the relationship between job accommodations for workers with poor health and work functioning impairment during the COVID-19 pandemic.MethodsAn internet survey was conducted in December 2020. We included 24,429 subjects for analysis. One question was used to determine whether subjects needed job accommodations from their company to continue working in their current health condition. The odds ratios (ORs) of the necessity of job accommodations for sick workers associated with work functioning impairment were estimated using multilevel logistic regression analysis.ResultsThe OR of work functioning impairment among sick workers not receiving job accommodations was 5.75 (95% confidence interval (CI) 5.34-6.20, p<0.001) and those receiving job accommodations was 1.88 (95% CI 1.69-2.08, p<0.001) compared to healthy workers.ConclusionsThis study suggests that providing job accommodations to workers with poor health may improve their work functioning impairment.
Antibody titers against the Alpha, Beta, Gamma, and Delta variants of SARS-CoV-2 induced by BNT162b2 vaccination measured using automated chemiluminescent enzyme immunoassay
Authors: Kato Hideaki , Miyakawa Kei , Ohtake Norihisa , Go Hirofumi , Yamaoka Yutaro , Yajima Satoshi , Shimada Tomoko , Goto Atsushi , Nakajima Hideaki , Ryo Akihide 
Published: September 2021

AbstractBackgroundLevels of 50% neutralizing titer (NT50) reflect a vaccine-induced humoral immunity after the vaccination against the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Measurements of NT50 are difficult to implement in large quantities. A high-throughput laboratory test is expected for determining the level of herd immunity against SARS-CoV-2.MethodsWe analyzed samples from 168 Japanese healthcare workers who had completed two doses of the BNT162b2 vaccine. We analyzed immunoglobulin G (IgG) index values against spike protein (SP) using automated chemiluminescent enzyme immunoassay system AIA-CL and analyzed the background factors affecting antibody titer. SP IgG index was compared with 50% neutralization titers.ResultsThe median SP IgG index values of the subjects (mean age = 43 years; 75% female) were 0.1, 1.35, 60.80, and 97.35 before and at 2, 4, and 6 weeks after the first dose, respectively. At 4 and 6 weeks after the first dose, SP IgG titers were found to have positive correlation with NT50 titer (r=0.7535 in 4 weeks; r=0.4376 in 6 weeks). Proportions of the SP IgG index values against the Alpha, Beta, Gamma, and Delta variants compared with the original strain were 2.029, 0.544, 1.017, and 0.6096 respectively. Older age was associated with lower SP IgG titer index 6 weeks after the first dose.ConclusionsSP IgG index values were raised at 3 weeks after two doses of BNT162b2 vaccination and have positive correlation with NT50. SP IgG index values were lower in the older individuals and against Beta and Delta strain.
Decrease of heart rate variability during exercise: an index of cardiorespiratory fitness
Authors: Mongin Denis , Chabert Clovis , Extremera Manuel Gomez , Hue Olivier , Courvoisier Delphine Sophie , Carpena Pedro , Bernaola Galvan Pedro Angel 
Published: September 2021

AbstractThe present study proposes to measure and quantify the heart rate variability (HRV) changes during effort and to test the capacity of the produced indices to predict cardiorespiratory fitness measures. Therefore, the beat-to-beat cardiac time interval series of 18 adolescent athletes (15.2 ± 2.0 years) measured during maximal graded effort test were detrended using a dynamical first-order differential equation model. Heart rate variability was then calculated as the standard deviation of the detrended RR intervals within successive windows of one minute. The variation of this measure of HRV during exercise is properly adjusted by an exponential decrease of the heart rate. The amplitude and the decay rate of this exponential trend are strongly associated with maximum oxygen consumption, maximal aerobic power, and ventilatory thresholds. It indicates that among athletes with better fitness, HRV has higher values at low heart rate and decreases faster when the heart rate increases during exercise. This analysis, based only on cardiac measurements, provides a promising tool for the study of cardiac measurements generated by portable devices.