Category: Nevin Manimala

Micron. 2024 Jul 8;185:103688. doi: 10.1016/j.micron.2024.103688. Online ahead of print.

ABSTRACT

Iterative phase retrieval is based on minimising a loss function as a measure of the consistency of an initial guess and underlying experimental data. Under ideal experimental conditions, real data contains Poissonian noise due to counting statistics. In this work, we use the Wirtinger Flow concept in combination with four common loss functions, being the L₁ loss, the mean-squared error (MSE), the amplitude loss and the Poisson loss. Since only the latter reflects the counting statistics as an asymmetric Poisson distribution correctly, our simulation study focuses on two main cases. Firstly, high-dose momentum-resolved scanning transmission electron microscopy (STEM) of an MoS₂ monolayer is considered for phase retrieval. In this case, it is found that the four losses perform differently with respect to chemical sensitivity and frequency transfer, which we interprete in terms of the substantially different signal level in the bright and dark field part of diffraction patterns. Remedies are discussed using further simulations, addressing the use of virtual ring detectors for the dark field, or restricting loss calculation to the bright field. Secondly, a dose series is presented down to 100 electrons per diffraction pattern. It is found that all losses yield qualitatively reasonable structural data in the phase, whereas only MSE and Poisson loss range at the correct amplitude level. Chemical contrast is, in general, reliably obtained using the Poisson concept, which also provides the most continuous spatial frequency transfer as to the reconstructed object transmission function.

PMID:38991624 | DOI:10.1016/j.micron.2024.103688

Mar Pollut Bull. 2024 Jul 10;206:116676. doi: 10.1016/j.marpolbul.2024.116676. Online ahead of print.

ABSTRACT

Understanding mercury (Hg) concentrations in mesopelagic and mid-trophic fishes is important for assessing Hg accumulation in oceanic ecosystems and higher-order predators. This study measured total Hg (THg) concentrations in the whole body of 16 abundant mesopelagic fish species sampled in two distinct sites within the Tasman Sea. Across all species, total Hg concentrations ranged from 0.02 to 0.48 μg g^-1 dry weight (0.01 to 0.15 μg g^-1 wet weight). Total Hg concentrations varied with vertical migration patterns, with shallower migrators exhibiting higher THg. Females typically had statistically higher THg concentrations than males. Positive correlations between THg concentration and standard length were observed for some but not all species. At the community level, THg concentrations correlated positively with estimated trophic position and foraging habitat, as inferred by stable isotope values. These findings contribute to our understanding of Hg cycling in oceanic ecosystems and the potential for biomagnification in oceanic top-order predators.

PMID:38991610 | DOI:10.1016/j.marpolbul.2024.116676

J Chromatogr A. 2024 Jul 5;1730:465143. doi: 10.1016/j.chroma.2024.465143. Online ahead of print.

ABSTRACT

The solvation parameter model uses six descriptors identified as excess molar refraction, E, dipolarity/polarizability, S, overall hydrogen-bond acidity, A, overall hydrogen-bond basicity, B, McGowan’s characteristic volume, V, and the gas-liquid partition constant on hexadecane at 25 °C, L to model the distribution of neutral compounds in biphasic systems. Abraham’s version of this model uses all six descriptors with two separate linear free energy relationship models for the transfer of compounds from a gas phase to a condensed phase and between condensed phases. Goss proposed a modification to this model that uses a single calibration model regardless of the physical state for each phase and five of the descriptors employed in Abraham’s model (E descriptor is eliminated). The capability of Abraham’s model and the Goss-modified model to characterize the contribution of intermolecular interaction to retention for gas and reversed-phase liquid chromatographic systems and distribution in liquid-liquid partition systems is evaluated using the WSU compound descriptor database. These more accurate values for the Abraham descriptors have not been utilized previously for the evaluation of the Goss-modified model and should be more capable of discerning subtle differences in model performance. It is shown that model quality defined by statistical parameters favors Abraham’s model over the Goss-modified model with differences in model quality greater for systems in which Abraham’s model indicates a significant contribution from electron lone pair interactions and for systems in which one phase is a solvent containing perfluoroalkyl substituents. There is a small systematic difference for the terms describing the combined contributions of cavity formation and dispersion interactions and for interactions of a dipole-type. The contribution of hydrogen-bonding interactions is virtually identical for the two models. The model intercepts are generally different and potentially assigned to a larger contribution from lack-of-fit for the Goss-modified model. Although the Abraham model descriptors have been routinely employed for applications using the Goss-modified model the possibility that Goss-model specific descriptors should be employed was evaluated. Using the Solver method and Goss-model specific calibration models for chromatographic and liquid-liquid partition systems a new set of Goss-specific descriptors was calculated for 28 varied compounds. These descriptors show good statistical agreement with the Abraham descriptor values with an average deviation of 0.009, -0.003, -0.004, and -0.023, respectively, for the S, A, B, and L descriptors, corresponding to a relative absolute deviation in percent of 2.2 %, 3.9 %, 4.3 %, and 1.2 %, respectively.

PMID:38991600 | DOI:10.1016/j.chroma.2024.465143

Obstet Gynecol. 2024 Jul 11. doi: 10.1097/AOG.0000000000005663. Online ahead of print.

ABSTRACT

OBJECTIVE: To evaluate the relationship between duration of labor during second-trimester medication abortion and adverse outcomes.

METHODS: We conducted a retrospective cohort study including all individuals with a singleton gestation undergoing second-trimester medication abortion without evidence of advanced cervical dilation, rupture of membranes, or preterm labor at four centers. The primary exposure was duration of labor (ie, hours spent from receiving misoprostol to fetal expulsion). The primary outcome was composite morbidity, defined as uterine rupture, need for blood transfusion, clinical chorioamnionitis, intensive care unit admission, or need for readmission. We performed bivariate and multivariate negative binomial analyses. A post hoc subgroup analysis was performed to assess for the risk of the primary outcome by gestational age. We performed tests of homogeneity based on history of uterine scarring and parity.

RESULTS: Six hundred eighty-one individuals were included. The median duration of labor was 11 hours (interquartile range 8-17 hours). One hundred thirty-one (19.2%) experienced the primary outcome. When duration of labor was evaluated continuously, a longer duration of labor was associated with an increased frequency of morbidity (adjusted β=0.68, 95% CI, 0.32-1.04). When duration of labor was evaluated categorically, those experiencing the highest quartile of duration (ie, 17 hours or more) had a statistically higher risk for experiencing morbidity compared with individuals in all other quartiles (adjusted relative risk 1.99, 95% CI, 1.34-2.96). When we focused on components of the composite outcome, clinical chorioamnionitis was significantly different between those experiencing a longer duration and those experiencing a shorter duration of labor (26.2% vs 10.6%, P<.001). On subgroup analysis, gestational age was not associated with the risk of composite morbidity. Tests of homogeneity demonstrated no significant difference in the risk for morbidity among individuals with a history of uterine scarring or based on parity.

CONCLUSION: Duration of labor was independently associated with risks for adverse maternal outcomes during second-trimester medication abortion, specifically clinical chorioamnionitis.

PMID:38991214 | DOI:10.1097/AOG.0000000000005663

J Glob Health. 2024 Jul 12;14:04109. doi: 10.7189/jogh.14.04109.

ABSTRACT

BACKGROUND: Preterm birth and low birth weight (PBLBW), recognised globally as primary contributors to infant mortality in children under five, have not been sufficiently investigated in terms of their worldwide impact. In this study we aimed to thoroughly evaluate the contemporary trends in disease burden attributable to PBLBW.

METHODS: We analysed data from 204 countries and territories between 1990-2019, as sourced from the 2019 Global Burden of Disease Study. We analysed the global incidence of mortality and disability-adjusted life years (DALYs) associated with PBLBW, stratified by age, gender, year, and geographic location, alongside the socio-demographic index (SDI). We calculated the annual percentage changes to evaluate the dynamic trends over time. We employed a generalised linear model and scrutinised the relationship between the SDI and the disease burden attributed to PBLBW.

RESULTS: In 2019, the global age-standardised rate of deaths and DALYs related to PBLBW showed significant declines. Over the period 1990-2019, both death and DALY rates displayed substantial downward trends, with similar change trends observed for both females and males. Age-specific ratios revealed a decrease in PBLBW-related deaths and DALYs with increasing age, primarily during the neonatal stages (zero to 27 days). The leading three causes of PBLBW-related DALYs in 2019 were neonatal disorders, lower respiratory infections, and sudden infant death syndrome. Furthermore, the association between SDI and PBLBW-related DALYs indicated that the age-standardised DALY rates in 204 countries and territories worldwide were negatively correlated with SDI in 2019. From 1990 to 2019, the age-standardised DALY rates decreased linearly in most regions, except sub-Saharan Africa.

CONCLUSIONS: The persistent global burden of disease associated with PBLBW is particularly pronounced in neonates aged less than 28 days and in regions with low SDI. In this study, we highlighted the critical need for tailored interventions aimed at mitigating the detrimental effects of PBLBW to attain specific sustainable development goals, particularly those centred on enhancing child survival and overall well-being.

PMID:38991211 | DOI:10.7189/jogh.14.04109

J Glob Health. 2024 Jul 12;14:04120. doi: 10.7189/jogh.14.04120.

ABSTRACT

BACKGROUND: Preterm birth (PTB) and its complications are important public health problems. Its aetiology is multifactorial and involves both modifiable and non-modifiable factors. Among the modifiable risk factors, micronutrient deficiencies, including maternal folate deficiency, are increasingly being studied in PTB. In this study, we estimated the prevalence of folate deficiency during pregnancy and examined its association with PTB among rural Bangladeshi women.

METHODS: We conducted a nested case-control study using data from a population-based cohort of 3000 pregnant women who were enrolled between 8 and 19 weeks of gestation following ultrasound confirmation of gestational age. Sociodemographic, epidemiologic, clinical, and pregnancy outcomes data were collected through home visits, while blood samples were collected at enrolment and 24-28 weeks of gestation during pregnancy. We included all women who delivered preterm (defined as live births <37 weeks of gestation) as cases (n = 235) and a random sample of women having a term birth as controls (n = 658). The main exposure was folate concentrations in maternal serum during 24-28 weeks of pregnancy. We categorised women into folate deficient (<3 ng/mL) and not deficient (≥3 ng/mL). We then performed multivariable logistic regression analysis to examine the association between maternal folate levels and PTB, adjusting for relevant covariates.

RESULTS: Thirty-eight per cent of the enrolled pregnant women were folate deficient. Maternal serum folate deficiency was significantly associated with PTB (adjusted OR (aOR) = 1.73; 95% confidence interval (CI) = 1.27-2.36). The risk of PTB was also higher among women who were of short stature (aOR = 1.83; 95% CI = 1.27-2.63), primiparous (aOR = 1.60; 95% CI = 1.15-2.22), and had exposure to passive smoking (aOR = 1.54; 95% CI = 1.02-2.31).

CONCLUSIONS: The prevalence of folate deficiency was high among pregnant women in rural Bangladesh, and folate deficiency was significantly associated with an increased risk of preterm birth.

PMID:38991209 | DOI:10.7189/jogh.14.04120

JCO Glob Oncol. 2024 Jul;10:e2400063. doi: 10.1200/GO.24.00063.

ABSTRACT

PURPOSE: Most patients with cancer will be hospitalized throughout the disease course. However, most evidence on the causes and outcomes of these hospitalizations comes from administrative data or small retrospective studies from high-income countries.

METHODS: This study is a retrospective cohort of patients with solid tumors hospitalized from February 1, 2021, to December 31, 2021, in a tertiary cancer center in São Paulo, Brazil. We collected data on cancer diagnosis, symptoms at admission, hospitalization diagnosis, and survival clinical outcomes during in-hospital stay (in-hospital mortality) and after discharge (readmission rates and overall survival [OS]). Progressive disease (PD) diagnosis during admission was retrieved from manual chart review if explicitly stated by the attending physician. We modeled in-hospital mortality and postdischarge OS with logistic regression and Cox proportional hazards models, respectively.

RESULTS: A total of 3,726 unique unplanned admissions were identified. The most common symptoms at admission were pain (40.6%), nausea (16.8%), and dyspnea (16.1%). PD (34.0%), infection (31.1%), and cancer pain (13.4%) were the most frequent reasons for admission. The in-hospital mortality rate was 18.9%. Patients with PD had a high in-hospital mortality rate across all tumor groups and higher odds of in-hospital death (odds ratio, 3.5 [95% CI, 3.0 to 4.2]). The 7-, 30-, and 90-day readmission rates were 11.9%, 33.5%, and 54%, respectively. The postdischarge median OS (mOS) was 12.6 months (95% CI, 11.6 to 13.7). Poorer postdischarge survival was observed among patients with PD (mOS, 5 months v 18 months; P < .001; hazard ratio, 2.4 [95% CI, 2.1 to 2.6]).

CONCLUSION: PD is a common diagnosis during unplanned hospitalizations and is associated with higher in-hospital mortality rates and poorer OS after discharge. Oncologists should be aware of the prognostic implications of PD during admission and align goals of care with their patients.

PMID:38991187 | DOI:10.1200/GO.24.00063

JCO Glob Oncol. 2024 Jul;10:e2300187. doi: 10.1200/GO.23.00187.

ABSTRACT

PURPOSE: Breast cancer (BC) is the most frequent neoplasm in women in Colombia and is associated with a higher mortality rate than in other countries and regions. Neoadjuvant chemotherapy (NACT) has become a standard treatment in locally advanced BC and provides an opportunity to improve clinical outcomes in BC. This study aims to describe characteristics, treatment patterns, and outcomes after NACT in a cohort of Colombian patients with BC.

METHODS: We performed a retrospective cohort study. We included adult patients with BC treated with NACT. Clinical charts were retrospectively reviewed. Descriptive statistics and time to event for overall survival analyses were performed. Recursive partitioning was performed for survival curves to assess the complex relationship between survival times and other variables.

RESULTS: Three hundred and fourteen patients were included for analysis. The pathologic complete response after neoadjuvant chemotherapy (ypCR) rate was 34.4%, with a higher ypCR in triple-negative BC (TNBC; 46.9%) and human epidermal growth factor receptor 2-positive BC (72.7%). Those who did not achieve ypCR had a higher percentage of death and relapse. The median follow-up was 4.9 years, with an 88.2% 5-year overall survival (OS).

CONCLUSION: A total of 62.6% of the total patients identified were not treated with NACT, indicating a low utilization. Our global ypCR rate was higher when compared with similar studies in Colombia, likely because of differences in the NACT treatment regimens. ypCR was only associated with OS in the TNBC subgroup, emphasizing the importance of pursuing ypCR in these patients. We consider the use of NACT a valuable opportunity to implement innovative treatment approaches that improve outcomes in Colombian patients with BC.

PMID:38991183 | DOI:10.1200/GO.23.00187

JCO Glob Oncol. 2024 Jul;10:e2400171. doi: 10.1200/GO.24.00171.

ABSTRACT

PURPOSE: Prostate cancer has emerged as a significant public health challenge in the Middle East, characterized by rising incidence rates and a concerning mortality-to-incidence ratio. Yet, despite these alarming trends, data regarding prostate cancer awareness in the region remain limited. To address this critical knowledge gap, this study investigates prostate cancer awareness within the Middle East.

MATERIALS AND METHODS: A cross-sectional survey was performed among 5,913 men age 40 years and older across 14 Middle Eastern countries between January 1, 2022, and July 31, 2023. Excluding those with a history of prostate cancer, a validated questionnaire assessed prostate cancer awareness. Data were analyzed using frequencies and percentages for categorical variables, medians and ranges for continuous variables, and Pearson chi-square analysis for relationships between education levels and awareness of prostate cancer.

RESULTS: The survey achieved a 74.9% response rate, with 4,431 male participants. Regarding prostate cancer awareness, 83.8% of participants had heard of the disease. However, only 31.0% correctly identified it as the most common malignancy in men, and 21.8% believed it affects both sex. Awareness of screening was limited, with just 19.1% recognizing the prostate-specific antigen test’s role. Additionally, participants had a pessimistic view, with a mean perception that 75% of patients with prostate cancer die from the disease, rather than from other causes. Higher education levels were associated with significantly increased awareness of prostate cancer (P < .001).

CONCLUSION: This study reveals that while general awareness of the disease exists, crucial knowledge deficits regarding risk factors, screening, and prognosis are evident. Addressing these knowledge gaps through culturally tailored education may improve early detection rates, treatment outcomes, and ultimately reduce the burden of prostate cancer in the Middle East.

PMID:38991182 | DOI:10.1200/GO.24.00171

JCO Precis Oncol. 2024 Jul;8:e2300715. doi: 10.1200/PO.23.00715.

ABSTRACT

PURPOSE: African American/Black (AA/B) individuals are under-represented in genomic databases and thus less likely to receive definitive information from germline genetic testing (GGT) than non-Hispanic White (NHW) individuals. With nearly 500,000 AA/B and NHW individuals having undergone multigene panel testing (MGPT) for hereditary cancer risk at a single commercial laboratory, to our knowledge, we present the largest study to date investigating cancer GGT results in AA/B and NHW individuals.

METHODS: MGPT results from a retrospective cohort of AA/B (n = 48,684) and NHW (n = 444,831) patients were evaluated. Frequencies of pathogenic germline variants (PGVs) and variants of uncertain significance (VUS) were compared between AA/B and NHW individuals. Changes in frequency of VUS over time were determined. Pearson’s chi-squared test was used to compare categorical variables among groups. All significance tests were two-tailed, and P < .05 was considered statistically significant.

RESULTS: Between 2015 and 2022, rates of VUS decreased 2.3-fold in AA/B and 1.8-fold in NHW individuals; however, frequencies of VUS and PGV remained significantly higher (46% v 32%; P < .0001) and lower (9% v 13%; P < .0001) in AA/B compared with NHW individuals. Rates of VUS in ATM, BRCA1, BRCA2, PALB2, and PMS2 were significantly higher in AA/B compared with NHW individuals, whereas rates of PGV in BRCA1, BRCA2, and PALB2 were higher in AA/B compared with NHW individuals (P < .001).

CONCLUSION: Despite reductions in VUS frequencies over time, disparities in definitive GGT results persist. Increasing inclusion of AA/B populations in both testing and research will further increase knowledge of genetic variants across these racial groups.

PMID:38991178 | DOI:10.1200/PO.23.00715