Category: Nevin Manimala

Int J Methods Psychiatr Res. 2024 Dec;33(4):e70006. doi: 10.1002/mpr.70006.

ABSTRACT

OBJECTIVES: To develop a composite score for differential resilience to effects of combat-related stressors (CRS) on persistent DSM-IV post-traumatic stress disorder (PTSD) among US Army combat arms soldiers using survey data collected before deployment.

METHODS: A sample of n = 2542 US Army combat arms soldiers completed a survey shortly before deployment to Afghanistan and then again two to three and 8-9 months after redeployment. Retrospective self-reports were obtained about CRS. Precision treatment methods were used to determine whether differential resilience to persistent PTSD in the follow-up surveys could be developed from pre-deployment survey data in a 60% training sample and validated in a 40% test sample.

RESULTS: 40.8% of respondents experienced high CRS and 5.4% developed persistent PTSD. Significant test sample heterogeneity was found in resilience (t = 2.1, p = 0.032), with average treatment effect (ATE) of high CRS in the 20% least resilient soldiers of 17.1% (SE = 5.5%) compared to ATE = 3.8% (SE = 1.2%) in the remaining 80%. The most important predictors involved recent and lifetime pre-deployment distress disorders.

CONCLUSIONS: A reliable pre-deployment resilience score can be constructed to predict variation in the effects of high CRS on persistent PTSD among combat arms soldiers. Such a score could be used to target preventive interventions to reduce PTSD or other resilience-related outcomes.

PMID:39475323 | DOI:10.1002/mpr.70006

Pharm Stat. 2024 Oct 30. doi: 10.1002/pst.2446. Online ahead of print.

ABSTRACT

An informed estimate of subject-level variance is a key determinate for accurate estimation of the required sample size for clinical trials. Evaluating completed adult Type 2 diabetes studies submitted to the FDA for accuracy of the variance estimate at the planning stage provides insights to inform the sample size requirements for future studies. From the U.S. Food and Drug Administration (FDA) database of new drug applications containing 14,106 subjects from 26 phase 3 randomized studies submitted to the FDA in support of drug approvals in adult type 2 diabetes studies reviewed between 2013 and 2017, we obtained estimates of subject-level variance for the primary endpoint-change in glycated hemoglobin (HbA1c) from baseline to 6 months. In addition, we used nine additional studies to examine the impact of clinically meaningful covariates on residual standard deviation and sample size re-estimation. Our analyses show that reduced sample sizes can be used without interfering with the validity of efficacy results for adult type 2 diabetes drug trials. This finding has implications for future research involving the adult type 2 diabetes population, including the potential to reduce recruitment period length and improve the timeliness of results. Furthermore, our findings could be utilized in the design of future endocrinology clinical trials.

PMID:39475306 | DOI:10.1002/pst.2446

Disaster Med Public Health Prep. 2024 Oct 30;18:e115. doi: 10.1017/dmp.2024.88.

ABSTRACT

OBJECTIVE: While many medical practitioners value the interactive nature of in-person conferences, results of these interactions are often poorly documented. The objective of this study was to pilot the Delphi method for developing consensus following a national conference and to compare the results between experts who did and did not attend.

METHODS: A 3-round Delphi included experts attending the 2023 Society of Disaster Medicine and Health Preparedness Annual Meeting and experts who were members of the society but did not attend. Conference speakers provided statements related to their presentations. Experts rated the statements on a 1-7 scale for agreement using STAT59 software (STAT59 Services Ltd, Edmonton, Alberta, Canada). Consensus was defined as a standard deviation of ≤ 1.0.

RESULTS: Seventy-five statements were rated by 27 experts who attended and 10 who did not: 2634 ratings in total. There was no difference in the number of statements reaching consensus in the attending group (26/75) versus that of the nonattending group (27/75) (P = 0.89). However, which statements reached consensus differed between the groups.

CONCLUSION: The Delphi method is a viable method to document consensus from a conference. Advantages include the ability to involve large groups of experts, statistical measurement of the degree of consensus, and prioritization of the results.

PMID:39475298 | DOI:10.1017/dmp.2024.88

Biometrics. 2024 Oct 3;80(4):ujae124. doi: 10.1093/biomtc/ujae124.

ABSTRACT

Mouse-tracking data, which record computer mouse trajectories while participants perform an experimental task, provide valuable insights into subjects’ underlying cognitive processes. Neuroscientists are interested in clustering the subjects’ responses during computer mouse-tracking tasks to reveal patterns of individual decision-making behaviors and identify population subgroups with similar neurobehavioral responses. These data can be combined with neuroimaging data to provide additional information for personalized interventions. In this article, we develop a novel hierarchical shrinkage partition (HSP) prior for clustering summary statistics derived from the trajectories of mouse-tracking data. The HSP model defines a subjects’ cluster as a set of subjects that gives rise to more similar (rather than identical) nested partitions of the conditions. The proposed model can incorporate prior information about the partitioning of either subjects or conditions to facilitate clustering, and it allows for deviations of the nested partitions within each subject group. These features distinguish the HSP model from other bi-clustering methods that typically create identical nested partitions of conditions within a subject group. Furthermore, it differs from existing nested clustering methods, which define clusters based on common parameters in the sampling model and identify subject groups by different distributions. We illustrate the unique features of the HSP model on a mouse tracking dataset from a pilot study and in simulation studies. Our results show the ability and effectiveness of the proposed exploratory framework in clustering and revealing possible different behavioral patterns across subject groups.

PMID:39475297 | DOI:10.1093/biomtc/ujae124

Biometrics. 2024 Oct 3;80(4):ujae121. doi: 10.1093/biomtc/ujae121.

ABSTRACT

This paper introduces a model for longitudinal functional data analysis that accounts for pointwise skewness. The proposed procedure decouples the marginal pointwise variation from the complex longitudinal and functional dependence using copula methodology. Pointwise variation is described through parametric distribution functions that capture varying skewness and change smoothly both in time and over the functional argument. Joint dependence is quantified through a Gaussian copula with a low-rank approximation-based covariance. The introduced class of models provides a unifying platform for both pointwise quantile estimation and prediction of complete trajectories at new times. We investigate the methods numerically in simulations and discuss their application to a diffusion tensor imaging study of multiple sclerosis patients. This approach is implemented in the R package sLFDA that is publicly available on GitHub.

PMID:39475296 | DOI:10.1093/biomtc/ujae121

Vet Med Sci. 2024 Nov;10(6):e70101. doi: 10.1002/vms3.70101.

ABSTRACT

Sperm cryopreservation is a rather complex process that needs to be adapted to wild and domestic bird species to ensure adequate efficiency. This study aimed to determine the usability of different cryoprotectants in the cryopreservation of Gloster canary sperm. For this purpose, sperm samples were collected from 12 2-year-old male Gloster canaries three times a week using cloacal massage for 4 weeks. After individual evaluation, sperm samples from the canaries were combined. Mixed sperm were divided into two groups in the study. Overall, 8% dimethyl sulfoxide (DMSO) and ethylene glycol (EG) were used as cryoprotectants. Sperm samples were drawn into straws after adding Dulbecco’s Modified Eagle Medium (DMEM) extender with high glucose ratio and two different cryoprotectants in a 1:1 ratio and frozen to -80°C with liquid nitrogen vapour and then stored in liquid nitrogen at -196°C. Frozen-thawed semen samples were evaluated regarding motility, vitality, plasma membrane integrity (hypoosmotic swelling test [HOST]), density and abnormal spermatozoa rate. The highest motility value after freezing and thawing was determined in the EG group with 31.667% ± 4.773%. In addition, vitality, plasma membrane integrity and normal sperm morphology were statistically significantly higher in the EG-frozen group, whereas head and tail abnormality was low (p < 0.05). This study determined that a DMEM extender containing 8% EG was more advantageous than a DMEM containing DMSO regarding spermatological parameters and could be used for long-term storage of canary sperm.

PMID:39474780 | DOI:10.1002/vms3.70101

Vet Med Sci. 2024 Nov;10(6):e70098. doi: 10.1002/vms3.70098.

ABSTRACT

BACKGROUND: Understanding the nature of inflammatory responses in cats with bacterial and viral infections is essential for accurately managing the infection. This study aimed to investigate the diversities of inflammatory responses between bacterial and viral infections in cats to figure out their role in the pathophysiology of these infections.

METHODS: Seventy-five owned cats were included in the study. The evaluations were performed based on three groups: healthy control, bacterial infection group (those with bronchopneumonia and gastrointestinal tract and urinary tract infections) and viral infection group (21 with feline coronavirus [FCoV], 3 with feline leukaemia virus [FeLV] and 1 with feline calicivirus), each containing 25 individuals. Total and differential leukocyte counts, C-reactive protein (CRP), transforming growth factor beta (TGF-β), interleukin-6 (IL-6), tumour necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β) and interleukin-10 (IL-10) concentrations were assessed in the blood samples collected from sick and healthy animals.

RESULTS: No statistically significant difference was noted in serum TNF-α, IL-1β and IL-10 concentrations of the infected cats (p = 0.996, p = 0.160 and p = 0.930, respectively). Serum TGF-β concentration in the viral infection group was reduced compared to the healthy control (p = 0.001). In contrast, WBC count and IL-6 and CRP concentrations were increased in the cats with bronchopneumonia, gastrointestinal tract infections and urinary tract infections compared to the healthy control and viral infection groups (p = 0.001, p = 0.001 and p = 0.001, respectively).

CONCLUSION: This study revealed significant differences between bacterial and viral infections regarding the fashion of inflammatory responses in cats, and the relevant data will undoubtedly contribute to the management and control of feline infectious diseases, rendering the development of novel therapeutic strategies.

PMID:39474776 | DOI:10.1002/vms3.70098

Vet Med Sci. 2024 Nov;10(6):e70106. doi: 10.1002/vms3.70106.

ABSTRACT

The guinea fowl (Numida meleagris) holds significant agricultural importance in Ghana, particularly in the Northern, Upper East and Upper West Regions. Despite their economic and cultural significance, guinea fowls face a potential threat from avian influenza, a global concern for its adverse impact on poultry populations. This study assessed the seroprevalence of the virus in mature guinea fowls in the Upper East Region. A cross-sectional survey was conducted in three districts within the Upper East Region from April to June 2023. Blood samples were collected from 397 guinea fowls that are over 4 weeks old, and seroprevalence was determined using ID Screen Influenza A Antibody Competition Enzyme-linked immunosorbent assay (ELISA). The study analysed demographic factors such as sex, age and source of birds, employing statistical methods to establish associations. Among the sampled guinea fowls, 24.7% tested positive for avian influenza antibodies, whereas 75.3% were seronegative. Age did not show statistically significant associations with seroprevalence, but intriguing patterns were observed. Adult guinea fowls exhibited higher seroprevalence (23.7%) compared to growers (1.0%). The source of birds showed no significant association, but birds from slaughter points demonstrated higher seroprevalence (11.6%) compared to households (5.0%) and live bird markets (8.1%). In conclusion, the study underscores the importance of monitoring avian influenza in guinea fowls to implement effective control measures. The presence of antibodies suggests guinea fowls may contribute to virus transmission in the Upper East Region. The study recommends ongoing nationwide surveillance to assess the true prevalence of avian influenza in guinea fowls across Ghana.

PMID:39474767 | DOI:10.1002/vms3.70106

J Int Med Res. 2024 Oct;52(10):3000605241288843. doi: 10.1177/03000605241288843.

ABSTRACT

OBJECTIVE: To conduct a systematic review and meta-analysis to assess the impact of transcranial electrical stimulation (TES), proposed as a potential therapy for post-stroke dysphagia, on swallowing function in stroke survivors.

METHODS: The PubMed, Embase, Web of Science, and Cochrane Library databases were searched for relevant studies on TES for post-stroke dysphagia. Search results were reviewed following PRISMA guidelines, and the following data were extracted from included studies: study characteristics, demographics, and outcomes. Bias was assessed using the Cochrane tool. Heterogeneity and effect sizes were analysed using I² statistics and appropriate effects models. The study protocol was registered with PROSPERO (registration No. CRD42024578243).

RESULTS: Six randomized controlled trials met the inclusion criteria (I² = 0.0%). The meta-analysis indicated a significant improvement in dysphagia with TES (standardized mean difference [SMD] 0.43, 95% confidence interval [CI] 0.13, 0.73). Subgroup analysis suggested that low-intensity TES was effective (SMD 0.46, 95% CI 0.09, 0.82), whereas high-intensity TES showed no significant improvement (SMD 0.37, 95% CI -0.17, 0.91). No publication bias was detected.

CONCLUSION: TES may improve swallowing in stroke patients, with potential benefits from low-intensity protocols.

PMID:39474766 | DOI:10.1177/03000605241288843

Epilepsia Open. 2024 Oct 30. doi: 10.1002/epi4.13067. Online ahead of print.

ABSTRACT

OBJECTIVE: Clinical studies indicated a link between DTI imaging characteristics and epilepsy, but the causality of this connection had not been established. Therefore, we employed the Mendelian randomization analysis method to determine the causal relationship between DTI imaging characteristics and epilepsy.

METHOD: We used Mendelian randomization analysis to identify the causal relationship between brain structure and the risk of epilepsy. GWAS data of DTI phenotypes, focal epilepsy, and genetic generalized epilepsy (GGE) were utilized in the analysis.

RESULTS: Our study found that DTI imaging phenotypes had a causal risk relationship with epilepsy. These phenotypes had a statistical impact on the risk of epilepsy seizures. There were differences in DTI phenotype causality between GGE and focal epilepsy, which were associated with the clinical phenotype differences of the two types of epilepsy.

SIGNIFICANCE: Our study demonstrated that the diagnosis of subtypes could be assisted by comparing the differences in DTI phenotypes of specific brain regions. This meant that by studying the changes in brain regions before the onset of epilepsy, we might be able to intervene in epilepsy at an earlier stage.

PLAIN LANGUAGE SUMMARY: Our study used Mendelian randomization to explore the causal relationship between brain structure, as seen in DTI imaging, and epilepsy. We found that specific DTI phenotypes are linked to an increased risk of epilepsy seizures, with notable differences between genetic generalized epilepsy and focal epilepsy. This suggested that analyzing DTI phenotypes could help in diagnosing and potentially intervening in epilepsy earlier by finding brain changes before seizures begin.

PMID:39474760 | DOI:10.1002/epi4.13067