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Clinical Microbiology Reviews Jan 2012Stenotrophomonas maltophilia is an emerging multidrug-resistant global opportunistic pathogen. The increasing incidence of nosocomial and community-acquired S.... (Review)
Review
Stenotrophomonas maltophilia is an emerging multidrug-resistant global opportunistic pathogen. The increasing incidence of nosocomial and community-acquired S. maltophilia infections is of particular concern for immunocompromised individuals, as this bacterial pathogen is associated with a significant fatality/case ratio. S. maltophilia is an environmental bacterium found in aqueous habitats, including plant rhizospheres, animals, foods, and water sources. Infections of S. maltophilia can occur in a range of organs and tissues; the organism is commonly found in respiratory tract infections. This review summarizes the current literature and presents S. maltophilia as an organism with various molecular mechanisms used for colonization and infection. S. maltophilia can be recovered from polymicrobial infections, most notably from the respiratory tract of cystic fibrosis patients, as a cocolonizer with Pseudomonas aeruginosa. Recent evidence of cell-cell communication between these pathogens has implications for the development of novel pharmacological therapies. Animal models of S. maltophilia infection have provided useful information about the type of host immune response induced by this opportunistic pathogen. Current and emerging treatments for patients infected with S. maltophilia are discussed.
Topics: Drug Resistance, Multiple, Bacterial; Global Health; Gram-Negative Bacterial Infections; Humans; Opportunistic Infections; Pandemics; Stenotrophomonas maltophilia
PubMed: 22232370
DOI: 10.1128/CMR.00019-11 -
Cardiovascular Diabetology Feb 2023The triglyceride-glucose (TyG) index and triglyceride to high-density lipoprotein cholesterol (TG/HDL-C) ratio, two simple surrogate indicators of insulin resistance,...
Triglyceride-glucose index and triglyceride to high-density lipoprotein cholesterol ratio as potential cardiovascular disease risk factors: an analysis of UK biobank data.
BACKGROUND
The triglyceride-glucose (TyG) index and triglyceride to high-density lipoprotein cholesterol (TG/HDL-C) ratio, two simple surrogate indicators of insulin resistance, have been demonstrated to predict cardiovascular disease (CVD). However, very few studies have investigated their associations with CVD in European populations.
METHODS
A total of 403,335 participants from the UK Biobank with data for TyG index and TG/HDL-C ratio and free from CVD at baseline were included. Cox models were applied to evaluate the association between TyG index and TG/HDL-C ratio and incident CVD. Mediation analyses were performed to evaluate the contribution of prevalent diabetes, hypertension, and dyslipidemia to observed associations.
RESULTS
During a median follow-up of 8.1 years, 19,754 (4.9%) individuals developed CVD, including 16,404 (4.1%) cases of CHD and 3976 (1.0%) cases of stroke. The multivariable-adjusted hazard ratios of total CVD in higher quartiles versus the lowest quartiles were 1.05, 1.05, and 1.19, respectively, for TyG index, and 1.07, 1.13, and 1.29, respectively, for TG/HDL-C ratio. There were significant trends toward an increasing risk of CVD across the quartiles of TyG index and TG/HDL-C ratio. In mediation analyses, dyslipidemia, type 2 diabetes, and hypertension explained 45.8%, 27.0%, and 15.0% of TyG index's association with CVD, respectively, and 40.0%, 11.8%, and 13.3% of TG/HDL-C ratio's association with CVD, respectively.
CONCLUSIONS
Elevated baseline TyG index and TG/HDL-C ratio were associated with a higher risk of CVD after adjustment for the well-established CVD risk factors. These associations were largely mediated by greater prevalence of dyslipidemia, type 2 diabetes, and hypertension.
Topics: Humans; Diabetes Mellitus, Type 2; Triglycerides; Cardiovascular Diseases; Cholesterol, HDL; Glucose; Biological Specimen Banks; Blood Glucose; Insulin Resistance; Hypertension; Dyslipidemias; United Kingdom; Risk Factors; Biomarkers
PubMed: 36797706
DOI: 10.1186/s12933-023-01762-2 -
Cureus Aug 2020Risk ratios, odds ratios, and hazard ratios are three common, but often misused, statistical measures in clinical research. In this paper, the authors dissect what each... (Review)
Review
Risk ratios, odds ratios, and hazard ratios are three common, but often misused, statistical measures in clinical research. In this paper, the authors dissect what each of these terms define, and provide examples from the medical literature to illustrate each of these statistical measures. Finally, the correct and incorrect methods to use these measures are summarized.
PubMed: 32983737
DOI: 10.7759/cureus.10047 -
Tropical Medicine & International... May 2022Phytate, an important component of plant origin foods, works as a chelator for mineral nutrients such as iron. Estimating the phytate-iron molar ratio is a traditional...
OBJECTIVE
Phytate, an important component of plant origin foods, works as a chelator for mineral nutrients such as iron. Estimating the phytate-iron molar ratio is a traditional method to assess the bioavailability of dietary iron, and a ratio >1 is suggestive of poor absorption of iron through the intestinal mucosa. In Bangladesh, the ratio is considerably higher; nonetheless, the haemoglobin and ferritin status are satisfactory. Hence, we appraised phytate-iron molar ratios and concomitant haemoglobin and ferritin status.
METHODS
Dietary intake of iron and phytate was estimated in non-pregnant non-lactating women and school-age children from a nationally representative survey. The phytate-iron molar ratios were estimated. Linear regressions on haemoglobin for the phytate-iron molar ratios and on molar ratios predicting inflammation-adjusted ferritin were performed.
RESULTS
The median ratios were 6.12 in women and 5.47 in children, with corresponding haemoglobin concentrations of 12.6 and 12.5 g/dl. Hypothetical lowering of the ratios by ~50% revealed a nominal increment of haemoglobin and ferritin.
CONCLUSION
The standard cut-off phytate-iron molar ratio of >1 is inconsistent with the iron and haemoglobin status of the Bangladeshi population. One plausible explanation for the inconsistency is a non-dietary environmental factor-groundwater iron. Isotope studies incorporating the iron from dietary and the drinking groundwater sources are needed to establish a ratio which might better explain iron bioavailability.
Topics: Bangladesh; Biological Availability; Child; Female; Ferritins; Humans; Iron; Iron, Dietary; Phytic Acid; Zinc
PubMed: 35383403
DOI: 10.1111/tmi.13750 -
Children (Basel, Switzerland) Aug 2023Regarding the hypertensive disorders of pregnancy, pre-eclampsia (PE) remains one of the leading causes of severe and life-threatening maternal and fetal complications.... (Review)
Review
The Current Role of the sFlt-1/PlGF Ratio and the Uterine-Umbilical-Cerebral Doppler Ultrasound in Predicting and Monitoring Hypertensive Disorders of Pregnancy: An Update with a Review of the Literature.
Regarding the hypertensive disorders of pregnancy, pre-eclampsia (PE) remains one of the leading causes of severe and life-threatening maternal and fetal complications. Screening of early-onset PE (<34 weeks of pregnancy), as well as late-onset PE (≥34 weeks), shows poor performance if based solely on clinical features. In recent years, biochemical markers from maternal blood-the pro-angiogenic protein placental growth factor (PlGF) and the antiangiogenic protein soluble FMS-like tyrosine kinase 1 (sFlt-1)-and Doppler velocimetry indices-primarily the mean uterine pulsatility index (PI), but also the uterine resistivity index (RI), the uterine systolic/diastolic ratio (S/D), uterine and umbilical peak systolic velocity (PSV), end-diastolic velocity (EDV), and uterine notching-have all shown improved screening performance. In this review, we summarize the current status of knowledge regarding the role of biochemical markers and Doppler velocimetry indices in early prediction of the onset and severity of PE and other placenta-related disorders, as well as their role in monitoring established PE and facilitating improved obstetrical surveillance of patients categorized as high-risk in order to prevent adverse outcomes. A sFlt-1/PlGF ratio ≤ 33 ruled out early-onset PE with 95% sensitivity and 94% specificity, whereas a sFlt-1/PlGF ≥88 predicted early-onset PE with 88.0% sensitivity and 99.5% specificity. Concerning the condition's late-onset form, sFlt-1/PlGF ≤ 33 displayed 89.6% sensitivity and 73.1% specificity in ruling out the condition, whereas sFlt-1/PlGF ≥ 110 predicted the condition with 58.2% sensitivity and 95.5% specificity. The cut-off values of the sFlt-1/PlGF ratio for the screening of PE were established in the PROGNOSIS study: a sFlt-1/PlGF ratio equal to or lower than 38 ruled out the onset of PE within one week, regardless of the pregnancy's gestational age. The negative predictive value in this study was 99.3%. In addition, sFlt-1/PlGF > 38 showed 66.2% sensitivity and 83.1% specificity in predicting the occurrence of PE within 4 weeks. Furthermore, 2018 ISUOG Practice Guidelines stated that a second-trimester mean uterine artery PI ≥ 1.44 increases the risk of later PE development. The implementation of a standard screening procedure based on the sFlt-1/PlGF ratio and uterine Doppler velocimetry may improve early detection of pre-eclampsia and other placenta-related disorders.
PubMed: 37761391
DOI: 10.3390/children10091430 -
American Journal of Epidemiology Nov 2023The classical Cornfield inequalities state that if a third confounding variable is fully responsible for an observed association between the exposure and the outcome...
The classical Cornfield inequalities state that if a third confounding variable is fully responsible for an observed association between the exposure and the outcome variables, then the association between both the exposure and the confounder, and the confounder and the outcome, must be at least as strong as the association between the exposure and the outcome, as measured by the risk ratio. The work of Ding and VanderWeele on assumption-free sensitivity analysis sharpens this bound to a bivariate function of the 2 risk ratios involving the confounder. Analogous results are nonexistent for the odds ratio, even though the conversion from odds ratios to risk ratios can sometimes be problematic. We present a version of the classical Cornfield inequalities for the odds ratio. The proof is based on the mediant inequality, dating back to ancient Alexandria. We also develop several sharp bivariate bounds of the observed association, where the 2 variables are either risk ratios or odds ratios involving the confounder.
Topics: Humans; Odds Ratio; Confounding Factors, Epidemiologic
PubMed: 37312597
DOI: 10.1093/aje/kwad137 -
Proceedings. Biological Sciences Jul 2021A wide range of literature connects sex ratio and mating behaviours in non-human animals. However, research examining sex ratio and human mating is limited in scope....
A wide range of literature connects sex ratio and mating behaviours in non-human animals. However, research examining sex ratio and human mating is limited in scope. Prior work has examined the relationship between sex ratio and desire for short-term, uncommitted mating as well as outcomes such as marriage and divorce rates. Less empirical attention has been directed towards the relationship between sex ratio and mate preferences, despite the importance of mate preferences in the human mating literature. To address this gap, we examined sex ratio's relationship to the variation in preferences for attractiveness, resources, kindness, intelligence and health in a long-term mate across 45 countries ( = 14 487). We predicted that mate preferences would vary according to relative power of choice on the mating market, with increased power derived from having relatively few competitors and numerous potential mates. We found that each sex tended to report more demanding preferences for attractiveness and resources where the opposite sex was abundant, compared to where the opposite sex was scarce. This pattern dovetails with those found for mating strategies in humans and mate preferences across species, highlighting the importance of sex ratio for understanding variation in human mate preferences.
Topics: Animals; Choice Behavior; Female; Humans; Male; Marriage; Reproduction; Sex Characteristics; Sex Ratio; Sexual Partners
PubMed: 34284630
DOI: 10.1098/rspb.2021.1115 -
Environment International Feb 2016Sensory effects in eyes and airways are common symptoms reported by aircraft crew and office workers. Neurological symptoms, such as headache, have also been reported.... (Review)
Review
Sensory effects in eyes and airways are common symptoms reported by aircraft crew and office workers. Neurological symptoms, such as headache, have also been reported. To assess the commonality and differences in exposures and health symptoms, a literature search of aircraft cabin and office air concentrations of non-reactive volatile organic compounds (VOCs) and ozone-initiated terpene reaction products were compiled and assessed. Data for tricresyl phosphates, in particular tri-ortho-cresyl phosphate (ToCP), were also compiled, as well as information on other risk factors such as low relative humidity. A conservative health risk assessment for eye, airway and neurological effects was undertaken based on a "worst-case scenario" which assumed a simultaneous constant exposure for 8h to identified maximum concentrations in aircraft and offices. This used guidelines and reference values for sensory irritation for eyes and upper airways and airflow limitation; a tolerable daily intake value was used for ToCP. The assessment involved the use of hazard quotients or indexes, defined as the summed ratio(s) (%) of compound concentration(s) divided by their guideline value(s). The concentration data suggest that, under the assumption of a conservative "worst-case scenario", aircraft air and office concentrations of the compounds in question are not likely to be associated with sensory symptoms in eyes and airways. This is supported by the fact that maximum concentrations are, in general, associated with infrequent incidents and brief exposures. Sensory symptoms, in particular in eyes, appear to be exacerbated by environmental and occupational conditions that differ in aircraft and offices, e.g., ozone incidents, low relative humidity, low cabin pressure, and visual display unit work. The data do not support airflow limitation effects. For ToCP, in view of the conservative approach adopted here and the rareness of reported incidents, the health risk of exposure to this compound in aircraft is considered negligible.
Topics: Air Pollution, Indoor; Aircraft; Eye; Hazardous Substances; Humans; Humidity; Occupational Exposure; Ozone; Respiratory System; Risk Assessment; Terpenes; Volatile Organic Compounds
PubMed: 26641522
DOI: 10.1016/j.envint.2015.11.008 -
Scientific Reports Sep 2022We created three types of vessel models: vessel volume, surface, and line models from swept-source optical coherence tomography images and tested experimentally...
We created three types of vessel models: vessel volume, surface, and line models from swept-source optical coherence tomography images and tested experimentally calculated three-dimensional (3D) biomarkers. The choroidal volume (CVolume), surface area (VSurface), and vessel length-associated index (VLI) were measured. The calculated 3D parameters were the mean choroidal thickness, choroidal vascularity index (CVI), vessel length density index (VLDI), vessel length to the stromal (VL-S) ratio, surface-to-volume ratio (S-V ratio), and vessel diameter index (VDI). Cluster analysis showed that the parameters were classified into two clusters: one was represented by the VVolume including the CVolume, VSurface, CVI, S-V ratio, VLI, VDI, and subfoveal choroidal thickness and the other by the VL-S ratio including the VLDI. Regarding the regional distribution, the VVolume, CVolume, VSurface, CVI, VLI, VL-S ratio, and VDI at the foveal center were higher than at the parafovea (P < 0.01). Although the VVolume decreased with age and axial length (AL) elongation, the association of the 3D parameters with age and AL elongation differed. The VLI, VLDI, VL-S ratio, and CVI decreased with age (P < 0.01) but not with AL elongation. The results suggested a structural difference in the choroidal vessel volume reduction between aging and AL elongation. The 3D parameters may provide additional information about the choroidal vasculature.
Topics: Biomarkers; Choroid; Fovea Centralis; Retinal Vessels; Tomography, Optical Coherence
PubMed: 36068250
DOI: 10.1038/s41598-022-17039-9 -
Journal of Geophysical Research.... Feb 2022The backscattering optical properties of an ensemble of randomly oriented dust particles at a wavelength of 355 nm were comprehensively studied by examining the...
The backscattering optical properties of an ensemble of randomly oriented dust particles at a wavelength of 355 nm were comprehensively studied by examining the invariant imbedding T-matrix results of the super-spheroid dust model. In particular, we focused on the lidar ratio ( ) and depolarization ratio ( ) relations of dust aerosols to aid interpretation of data from the Atmospheric Lidar (ATLID) instrument that will be onboard the Earth Cloud, Aerosol and Radiation Explorer (EarthCARE) satellite. Super-spheroid models with various aspect ratios ( ), roundness parameters , and refractive indices were investigated over a wide range of particle sizes and compared to the observation data of the National Aeronautics and Space Administration (NASA) Langley 355-nm airborne high spectral resolution lidar. We found that super-spheroid dust particles with different sets of and could be used to model almost the entire range of the observed joint distributions of and . The relation could effectively discriminate among dust particle types. The observed and values with the largest population density were best covered by models with > 2, especially by those with varying from 2.4 to 3.0.
PubMed: 35865334
DOI: 10.1029/2021JD035629