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1.
Phys Med Biol ; 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38942035

RESUMEN

OBJECTIVE: A major challenge in treatment of tumors near skeletal muscle is defining the target volume for suspected tumor invasion into the muscle. This study develops a framework that generates radiation target volumes with muscle fiber orientation directly integrated into their definition. The framework is applied to nineteen sacral tumor patients with suspected infiltration into surrounding muscles. Approach. To compensate for the poor soft-tissue contrast of CT images, muscle fiber orientation is derived from cryo-images of two cadavers from the Human Visible Project (VHP). The approach consists of (a) detecting image gradients in the cadaver images representative of muscle fibers, (b) mapping this information onto the patient image, and (c) embedding the muscle fiber orientation into an expansion method to generate patient-specific clinical target volumes (CTV). The validation tested the consistency of image gradient orientation across VHP subjects for the piriformis, gluteus maximus, paraspinal, gluteus medius, and gluteus minimus muscles. The model robustness was analyzed by comparing CTVs generated using different VHP subjects. The difference in shape between the new CTVs and standard CTV was analyzed for clinical impact. Main results. Good agreement was found between the image gradient orientation across VHP subjects, as the voxel-wise median cosine similarity was at least 0.86 (for the gluteus minimus) and up to 0.98 for the piriformis. The volume and surface similarity between the CTVs generating from different VHP subjects was on average at least 0.95 and 5.13 mm for the Dice Similarity Coefficient and the Hausdorff 95% Percentile Index, showing excellent robustness. Finally, compared to the standard CTV with different margins in muscle and non-muscle tissue, the new CTV margins are reduced in muscle tissue depending on the chosen clinical margins. Significance. This study implements a method to integrate muscle fiber orientation into the target volume without the need for additional imaging.

2.
J Nucl Med ; 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38871390

RESUMEN

Interreader and intrareader reproducibility of 18F-flotufolastat PET/CT scans in newly diagnosed and recurrent prostate cancer patients was assessed from masked image evaluations from two phase 3 studies. Methods: 18F-flotufolastat PET/CT images of newly diagnosed (n = 352) or recurrent (n = 389) patients were evaluated by 3 masked readers. Cohen κ was used to assess pairwise patient- and region-level interreader agreement. Agreement among all readers was assessed using Fleiss κ. Intrareader agreement between the first and repeat read (20% of images, ≥4 wk later) was assessed using Cohen κ. Results: Pairwise interreader agreement was 95% or better (newly diagnosed) and 75% or better (recurrent). The κ coefficients were impacted by the high-agreement-low-κ paradox: Cohen κ ranged from not estimable to 0.55, whereas Fleiss κ was 0.50 (newly diagnosed) and 0.41 (recurrent). Agreement was highest in the prostate of newly diagnosed patients (≥95%) and in the pelvic lymph nodes in recurrent patients (≥87%). Intrareader agreement was 86% or better across both populations. Conclusion: 18F-flotufolastat PET/CT images can be reliably interpreted, with a high degree of inter- and intrareader agreement.

3.
Rheumatol Adv Pract ; 8(2): rkae059, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38854416

RESUMEN

Objective: Recently, a genome-wide association study identified an association between RA-associated interstitial lung disease (ILD) and RPA3-UMAD1 rs12702634 in the Japanese population, especially for patients with a usual interstitial pneumonia (UIP) pattern. We aimed to replicate this association in a European population and test for interaction with MUC5B rs35705950. Methods: In this genetic case-control association study, patients with RA and ILD and controls with RA and no ILD were included from France, the USA and the Netherlands. Only cases and controls from European genetic ancestries determined by principal components analysis were included in the analyses. RA was defined by the 1987 ACR or 2010 ACR/EULAR criteria and ILD by chest high-resolution CT scan, except in the control dataset from the Netherlands, where the absence of ILD was determined by chart review. Patients were genotyped for RPA3-UMAD1 rs12702634 and MUC5B rs35705950. Associations were tested using logistic regression adjusted for sex, age at RA onset, age at ILD onset or at certified absence of ILD, tobacco smoking status and country of origin. Results: Among the 883 patients included, 322 were RA-ILD cases (36.5%). MUC5B rs35705950 was strongly associated with RA-ILD in all datasets {combined adjusted odds ratio [OR] 2.9 [95% CI 2.1, 3.9], P = 1.1 × 10-11. No association between RPA3-UMAD1 rs12702634 and RA-ILD was observed [combined OR 1.2 (95% CI 0.8, 1.6), P = 0.31. No interaction was found between RPA3-UMAD1 rs12702634 and MUC5B rs35705950 (P = 0.70). Conclusion: Our findings did not support a contribution of RPA3-UMAD1 rs12702634 to the overall RA-ILD susceptibility in the European population.

4.
medRxiv ; 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38883788

RESUMEN

Background: We have shown that ω3 polyunsaturated fatty acids (PUFAs) reduce risk for heart failure, regardless of ejection fraction status. Ventricular remodeling and reduced ventricular performance precede overt hear failure, however there is little insight into how PUFAs contribute to maladaptive signaling over time. PUFAs are agonists for regulatory activity at g-protein coupled receptors such as Ffar4, and downstream as substrates for monooxygenases (e.g lipoxygenase, cytochrome p450, or cyclooxygenase (COX)) which mediate intracellular adaptive signaling. Methods: Plasma phospholipid PUFA abundance at Exam 1 as mass percent EPA, DHA, and arachidonic acid (AA) from the Multi-Ethnic Study of Atherosclerosis (MESA) were evaluated using pathway modeling to determine the association with time-dependent changes in left ventricular (LV) mass (LVM), end-diastolic LV volume (EDV), and end-systolic volume (ESV) measured by cardiac MRI at Exams 1 and 5. Ejection fraction (EF) and mass:volume (MV) were calculated posteriorly from the first three. Results: 2,877 subjects had available MRI data. Participants with low AA and EPA had accelerated age-dependent declines in LVM. Males with low AA and EPA also had accelerated declines in EDV, but among females there was no PUFA association with EDV declines and exam 5 EDV status was positively associated with AA. Both sexes had nearly the same positive association of AA with changes in ESV. Conclusion: Plasma phospholipid AA and EPA are prospectively associated with indices of heart remodeling, including ventricular remodeling and performance. Combined AA and EPA scarcity was associated with the most accelerated age-related changes and exam 5 status, while the greatest benefits were found among participants with both PUFAs. This suggests that both PUFAs are required for optimal slowing of age-related declines in ventricular function.

5.
J Sports Sci ; : 1-9, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38922324

RESUMEN

The study examined acute effects of dryland muscular endurance (ME) and maximum strength (MS) sessions on performance, physiological, and biomechanical variables during a subsequent sprint swimming session. Twenty-seven swimmers (16.5 ± 2.6 yrs) completed three experimental conditions including: i) ME, 55% of 1-repetition maximum, ii) MS, 90% of 1-repetition maximum, and iii) control (CON, no dry-land). Twenty minutes following ME, MS and CON sessions swimmers performed a 10-s tethered swimming sprint, four by 50-m (4 × 50-m), and a 100-m front crawl sprints. Performance time, blood lactate, heart rate (HR), stroke rate (SR), stroke length (SL), stroke index (SI), and stroke efficiency (ηF) were measured during 4 × 50-m and 100-m. Hand grip strength (HG), and shoulder muscles isometric strength (ISO) were measured after each session. Mean 4 × 50-m time increased in ME compared to CON by 1.7 ± 2.7% (p = 0.01), while 100-m time was similar among conditions (p > 0.05). ISO was lower after dry-land training in all conditions (p = 0.01). Tethered force, HG, HR, SR, SL, SI, and ηF were no different between conditions (p > 0.05). Dryland ME session decrease swimming performance; however, ME and MS sessions did not affect technical ability during a subsequent maximum intensity swimming.

6.
Semin Perinatol ; : 151927, 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38897828

RESUMEN

Early nutritional exposures, including during embryogenesis and the immediate postnatal period, affect offspring outcomes in both the short- and long-term. Alterations of these modifiable exposures shape the developing gut microbiome, intestinal development, and even neurodevelopmental outcomes. A gut-brain axis exists, and it is intricately connected to early life feeding and nutritional exposures. Here, we seek to discuss the (1) origins of the gut-brain access and relationship with neurodevelopment, (2) components of human milk (HM) beyond nutrition and their role in the developing newborn, and (3) clinical application of nutritional practices, including fluid management and feeding on the development of the gut-brain axis, and long-term neurodevelopmental outcomes. We conclude with a discussion on future directions and unanswered questions that are critical to provide further understanding and insight into how clinicians and healthcare providers can optimize early nutritional practices to ensure children not only survive, but thrive, free of neurodevelopmental impairment.

7.
RMD Open ; 10(2)2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38886003

RESUMEN

OBJECTIVE: To compare longitudinal changes in spirometric measures between patients with rheumatoid arthritis (RA) and non-RA comparators. METHODS: We analysed longitudinal data from two prospective cohorts: the UK Biobank and COPDGene. Spirometry was conducted at baseline and a second visit after 5-7 years. RA was identified based on self-report and disease-modifying antirheumatic drug use; non-RA comparators reported neither. The primary outcomes were annual changes in the per cent-predicted forced expiratory volume in 1 s (FEV1%) and per cent predicted forced vital capacity (FVC%). Statistical comparisons were performed using multivariable linear regression. The analysis was stratified based on baseline smoking status and the presence of obstructive pattern (FEV1/FVC <0.7). RESULTS: Among participants who underwent baseline and follow-up spirometry, we identified 233 patients with RA and 37 735 non-RA comparators. Among never-smoking participants without an obstructive pattern, RA was significantly associated with more FEV1% decline (ß=-0.49, p=0.04). However, in ever smokers with ≥10 pack-years, those with RA exhibited significantly less FEV1% decline than non-RA comparators (ß=0.50, p=0.02). This difference was more pronounced among those with an obstructive pattern at baseline (ß=1.12, p=0.01). Results were similar for FEV1/FVC decline. No difference was observed in the annual FVC% change in RA versus non-RA. CONCLUSIONS: Smokers with RA, especially those with baseline obstructive spirometric patterns, experienced lower FEV1% and FEV1/FVC decline than non-RA comparators. Conversely, never smokers with RA had more FEV1% decline than non-RA comparators. Future studies should investigate potential treatments and the pathogenesis of obstructive lung diseases in smokers with RA.


Asunto(s)
Artritis Reumatoide , Fumar , Espirometría , Humanos , Artritis Reumatoide/diagnóstico , Artritis Reumatoide/fisiopatología , Masculino , Femenino , Persona de Mediana Edad , Estudios Longitudinales , Estudios Prospectivos , Fumar/efectos adversos , Fumar/epidemiología , Anciano , Volumen Espiratorio Forzado , Capacidad Vital , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/etiología , Adulto , Reino Unido/epidemiología
10.
Behav Pharmacol ; 35(5): 269-279, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38847447

RESUMEN

Excessive prescribing and misuse of prescription opioids, such as oxycodone, significantly contributed to the current opioid crisis. Although oxycodone is typically consumed orally by humans, parenteral routes of administration have primarily been used in preclinical models of oxycodone dependence. To address this issue, more recent studies have used oral self-administration procedures to study oxycodone seeking and withdrawal in rodents. Behavioral differences, however, following oral oxycodone intake versus parenteral oxycodone administration remain unclear. Thus, the goal of the current studies was to compare anxiety- and withdrawal-like behaviors using established opioid dependence models of either home cage oral intake of oxycodone (0.5 mg/ml) or repeated subcutaneous (s.c.) injections of oxycodone (10 mg/kg) in male and female mice. Here, mice received 10 days of oral or s.c. oxycodone administration, and following 72 h of forced abstinence, anxiety- and withdrawal-like behaviors were measured using elevated zero maze, open field, and naloxone-induced precipitated withdrawal procedures. Global withdrawal scores were increased to a similar degree following oral and s.c. oxycodone use, while both routes of oxycodone administration had minimal effects on anxiety-like behaviors. When examining individual withdrawal-like behaviors, mice receiving s.c. oxycodone exhibited more paw tremors and jumps during naloxone-induced precipitated withdrawal compared with oral oxycodone mice. These results indicate that both models of oxycodone administration are sufficient to elevate global withdrawal scores, but, when compared with oral consumption, s.c. oxycodone injections yielded more pronounced effects on some withdrawal-like behaviors.


Asunto(s)
Analgésicos Opioides , Ansiedad , Ratones Endogámicos C57BL , Oxicodona , Síndrome de Abstinencia a Sustancias , Animales , Oxicodona/farmacología , Oxicodona/administración & dosificación , Masculino , Femenino , Administración Oral , Inyecciones Subcutáneas , Ratones , Analgésicos Opioides/farmacología , Analgésicos Opioides/administración & dosificación , Trastornos Relacionados con Opioides , Naloxona/farmacología , Naloxona/administración & dosificación , Conducta Animal/efectos de los fármacos , Antagonistas de Narcóticos/farmacología , Antagonistas de Narcóticos/administración & dosificación
11.
Emerg Infect Dis ; 30(7): 1425-1429, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38848249

RESUMEN

During March and April 2024, we studied dairy cattle specimens from a single farm in Texas, USA, using multiple molecular, cell culture, and next-generation sequencing pathogen detection techniques. Here, we report evidence that highly pathogenic avian influenza A(H5N1) virus strains of clade 2.3.4.4b were the sole cause of this epizootic.


Asunto(s)
Enfermedades de los Bovinos , Subtipo H5N1 del Virus de la Influenza A , Animales , Texas/epidemiología , Bovinos , Subtipo H5N1 del Virus de la Influenza A/genética , Subtipo H5N1 del Virus de la Influenza A/aislamiento & purificación , Enfermedades de los Bovinos/virología , Enfermedades de los Bovinos/epidemiología , Filogenia , Gripe Aviar/virología , Gripe Aviar/epidemiología , Industria Lechera , Femenino
12.
Int J Infect Dis ; : 107146, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38945434

RESUMEN

OBJECTIVE: This study sought to detect and characterize influenza A (IAV) and influenza D (IDV) viruses circulating among commercial birds and shop owners in Pakistan's live bird markets. METHODS: Oropharyngeal swabs (n=600; n=300 pools) collected from poultry and nasopharyngeal swabs (n=240) collected from poultry workers were studied for molecular evidence of IAV and IDV using real-time and conventional RT-PCR protocols. RESULTS: Nineteen (6.3%) poultry pools were positive for IAV and 73.9% of these were positive for H9N2 subtypes. Two (0.83%) poultry workers had evidence of IAV, and both were also H9N2 subtypes. The poultry and human influenza A-positive specimens all clustered phylogenetically by Sanger and next-generation sequencing with previously detected H9N2 poultry isolates. No field specimens were positive for IDV. CONCLUSION: H9N2 IAV is likely enzootic in Punjab Province Pakistan's live bird markets and may be colonizing the noses of workers and market visitors. Regular monitoring for avian influenza-associated human illness in Punjab seems to be a needed public measure.

13.
Nat Commun ; 15(1): 4736, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38830886

RESUMEN

Earthquakes are rupture-like processes that propagate along tectonic faults and cause seismic waves. The propagation speed and final area of the rupture, which determine an earthquake's potential impact, are directly related to the nature and quantity of the energy dissipation involved in the rupture process. Here, we present the challenges associated with defining and measuring the energy dissipation in laboratory and natural earthquakes across many scales. We discuss the importance and implications of distinguishing between energy dissipation that occurs close to and far behind the rupture tip, and we identify open scientific questions related to a consistent modeling framework for earthquake physics that extends beyond classical Linear Elastic Fracture Mechanics.

14.
Am J Trop Med Hyg ; 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38889708

RESUMEN

Engagement is an important component in the advancement of gene-drive vector control research programs as developers look to transition the technology from the laboratory to the field. As research advances and engagement surrounding this novel technology is put into practice, knowledge can be gained from practical experiences and applications in the field. A relationship-based model (RBM) provides a framework for end-user development of engagement programs and strategies. The model places end users at the center of the engagement decision-making processes rather than as recipients of predetermined strategies, methods, and definitions. Successful RBM application for healthcare delivery has previously been demonstrated, and the University of California Malaria Initiative (UCMI) has applied this model to its gene-drive program in the Democratic Republic of São Tomé and Príncipe. The model emphasizes the importance of local leadership in the planning, development, and implementation of all phases of project engagement. The primary aim of this paper is to translate the model from paper to practice and provide a transparent description, using practical examples, of the UCMI program implementation of RBM at its field site. End-user development of the UCMI engagement program provides a unique approach to the development of ethical, transparent, and effective engagement strategies for malaria control programs. This paper may also serve as a reference and example for projects looking to establish an engagement program model that integrates end-user groups in the decision-making processes surrounding engagement.

15.
J Vasc Interv Radiol ; 2024 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-38914159

RESUMEN

PURPOSE: To assess the effect of cryoablation on renal function (measured by eGFR or serum creatinine) for treating Stage I renal cancer. MATERIALS AND METHODS: MEDLINE, EMBASE, and the CENTRAL databases were systematically searched from inception to May 1, 2023. Cohort studies that included data on change of estimated glomerular filtration rate (eGFR) and serum creatinine increase were included. Meta-analysis was performed by measuring the weighted mean difference and by fitting random-effect models. RESULTS: Overall, 38 studies were included, comprising of 3,202 participants. Percutaneous cryoablation was associated with an absolute eGFFR reduction of -3.06 ml/min/1.73 m2 (95% CI: -4.12 to -2.01; p-value < 0.001) and serum creatinine increase of 0.05 mg/dl (95% CI: -0.02 to 0.11; p-value> 0.05). The weighted absolute mean difference of percutaneous cryoablation for treating stage T1b renal cell carcinoma was estimated at -5.19 ml/min/1.73 m2 (95% CI: -11.1 to 0.72; p-value > 0.05). Lastly, when analyzing studies that included cohorts with solitary kidneys, the pooled weighted mean difference was estimated as -3.27 ml/min/1.73 m2 (95% CI: -6.79 to 0.25; pvalue >0.05). CONCLUSIONS: Percutaneous cryoablation for Stage 1 renal cell carcinoma has minimal significant impact on renal function (measured by eGFR or serum creatinine). The same outcome was observed in patients with larger tumors (T1b) and those with solitary kidneys.

16.
Artículo en Inglés | MEDLINE | ID: mdl-38838083

RESUMEN

BACKGROUND: Sensitivity to the adverse post-ingestive effects of ethanol likely serves as a deterrent to initiate alcohol consumption early in drinking and later may contribute to efforts to remain abstinent. Administering ethanol to naïve rats prior to Pavlovian conditioning procedures elicits robust ethanol-conditioned taste and place avoidance (CTA; CPA) mediated by its subjective interoceptive properties. The insular cortex (IC) has been implicated as a region involved in mediating sensitivity to the interoceptive properties of ethanol. Here, we examined whether bilateral lesions of the IC affect the acquisition and expression of taste and place avoidance in ethanol-induced CTA and CPA paradigms. METHODS: Adult male and female Wistar rats received bilateral excitotoxic lesions (ibotenic acid; 20 mg/mL; 0.3 µL) of the IC prior to conditioning procedures. Subsequently, rats were conditioned to associate a novel taste stimulus (0.1% saccharin) and context with the effects of ethanol (1.0 g/kg) in a combined CTA/CPP procedure. Conditioning occurred over 8 alternating CS+/CS- days, followed by tests for expression of taste and place preferences. Data from IC-lesioned rats were compared with neurologically intact rats. RESULTS: Our findings revealed that neurologically intact rats showed a significantly stronger ethanol-induced CTA than IC-lesioned rats. There were no significant differences in total fluid intake when rats consumed water (CS-). As with CTA effects, intact rats showed a strong CPA, marked by a greater reduction in time spent on the drug-paired context, while IC-lesioned rats failed to display CPA to ethanol. CONCLUSION: These results indicate that proper IC functioning is necessary for responding to the adverse interoceptive properties of ethanol regardless of which Pavlovian paradigm is used to assess interoceptive responsivity to ethanol. Blunted IC functioning from chronic ethanol use may reduce interoceptive signaling specifically of ethanol's adverse effects thus contributing to increased alcohol use.

17.
Artículo en Inglés | MEDLINE | ID: mdl-38695191

RESUMEN

OBJECTIVES: Custodial grandparents are grandparents who raise grandchildren on a full-time basis in absence of the grandchild's birth parents. Compared to noncaregiving grandparents, custodial grandparents report poorer mental and physical health and stronger changes in daily well-being when experiencing negative and positive events. We examine whether an online social intelligence training (SIT) program improves custodial grandmothers' (CGM) daily well-being, socioemotional skills, and changes in well-being when confronted with daily negative and positive events. METHODS: Multilevel models were applied to 200 CGM who were recruited from across the United States and completed a daily survey for 14 consecutive days prior to and following participation in a randomized clinical trial. Participants were randomized into the SIT program or an attention control condition focusing on healthy living habits. The outcomes of interest were daily well-being, social connectedness, emotional awareness, and perspective-taking. RESULTS: Multilevel analyses revealed that participants who participated in the SIT program, compared to the attention control condition, exhibited stronger emotional responsiveness (i.e., improvements) to daily positive events in the outcomes of positive affect, social engagement, and perspective-taking. DISCUSSION: Our findings illustrate that SIT improves key components of daily functioning in CGM, which may serve as a pathway linking the demands of custodial grandparenting to poorer mental and physical health. Our discussion focuses on the utility and accessibility of the SIT program for helping improve outcomes for this disadvantaged population.Clinical Trials Registration Number: NCT03239977.


Asunto(s)
Abuelos , Humanos , Femenino , Abuelos/psicología , Anciano , Persona de Mediana Edad , Masculino , Relaciones Intergeneracionales
18.
Artículo en Inglés | MEDLINE | ID: mdl-38775944

RESUMEN

RATIONALE: Nicotine dependence is highly comorbid with opioid use disorders (OUDs). The use of nicotine-containing products increases the propensity to misuse prescription opioids and addressing both nicotine and opioid use simultaneously is more efficacious for treatment of OUDs than treating opioid use alone. OBJECTIVES: Given this extreme comorbidity, further elucidation of the effects of nicotine as a factor in promoting vulnerability to development of OUDs is needed. Here, we sought to further explore the effects of nicotine administration on operant self-administration of remifentanil (RMF), a fast-acting synthetic µ-opioid receptor agonist, using a heterogenous seeking-taking chain schedule of reinforcement in unpunished and punished conditions. METHODS: Male and female rats received nicotine (0.4 mg/kg) or saline prior to operant self-administration sessions. These sessions consisted of pressing a 'seeking' lever to gain access to a 'taking' lever that could be pressed for delivery of 3.2 µg/kg RMF. After acquisition, continued drug seeking/taking was punished through contingent delivery of foot-shock. RESULTS: Nicotine, relative to saline, increased RMF consumption. Furthermore, nicotine treatment resulted in significantly higher seeking responses and cycles completed, and this effect became more pronounced during punished sessions as nicotine-treated rats suppressed RMF seeking significantly less than controls. Nicotine treatment functionally reduced the efficacy of foot-shock punishment as a deterrent of opioid-seeking. CONCLUSIONS: Nicotine administration enhanced both appetitive and consummatory responding for RMF and engendered a punishment-insensitive phenotype for RMF that was less impacted by contingent administration of foot-shock punishment. These findings provide further support for the hypothesis that nicotine augments vulnerability for addiction-like behaviors for opioids.

19.
J Phys Condens Matter ; 36(34)2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38729203

RESUMEN

The model of an ideal polymer chain in a harmonic applied field has broad applicability in situations involving polymer confinement and deformation due to applied stress. In this work we (1) formulate a general analytical model for a continuous Gaussian chain under a harmonic applied potential and (2) evaluate the statistical mechanics of this model given the potential, obtaining partition functions and moment generating functions (MGFs) that describe the chain configurations. Closed-form expressions for the squared radius of gyration, potential energy, partition function, and MGF for the center of mass are obtained for a general and multidimensional harmonic field. The expressions are compared with results of Monte Carlo simulations of a discrete Gaussian chain as well as results for related systems obtained from the literature. The theory derived here is used to test the applicability of the current model assumptions to relations from the literature describing polymer confinement and deformation in experiment, theory, and simulations.

20.
PLoS One ; 19(5): e0288567, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38753837

RESUMEN

BACKGROUND: The novel SARS-CoV-2 virus that causes Coronavirus disease (COVID-19) has redefined global health and response to Acute Respiratory Infection (ARI). The outbreak of a cluster of influenza-like illnesses in Wuhan, China, has morphed into a pandemic in the last quarter of 2019, stretching from South East Asia to Europe, The Americas, Africa, and the Australian subcontinent. We evaluated the prevalence of depression among outpatients diagnosed with ARI. MATERIALS AND METHODS: We utilized a cross-sectional, observational design and investigated the prevalence of symptoms of depression among outpatients with ARI and described the characteristics of outpatients with ARI in Kaduna State. RESULTS: The prevalence of symptoms of depression was 19.6% for respondents with symptoms of ARI and 14.4% for those without symptoms of ARI. On no risk of depression, we had a higher proportion of the respondents without symptoms of ARI (86%) than those with symptoms of depression (80%) (M = 318.4, SD = 29.62 case, and M = 344.0, SD = 14.2 control, r = 0.88, CI = 13.5 to 6.5, P = 0.000952). Likewise, in the category with mild risk of depression, respondents without symptoms of ARI were fewer (10%) than those with symptoms of depression (15%) (M = 58.4, SD = 26.0 case, and M = 42.1, SD = 12.7 control, r = 0.86, CI = 11.8 to 5.8, P = 0.0136. There was no significant difference between respondents with symptoms of ARI and without symptoms of ARI in the categories of moderate (M = 13.6, SD = 5.1 case, and M = 11.6, SD = 4.6 control, r = 0.87, CI = 2.3 to 2.1, P = 0.178) and high (M = 5.6, SD = 2.5 case, and M = 4.4, SD = 3.2 control, r = 0.61, CI = 1.2 to 1.5, P = 0.174) risk of depression. CONCLUSION: Symptoms of depression were commoner among respondents who presented with symptoms of Acute Respiratory Infection (ARI) at the Outpatient Department (OPD). However, further explanatory research is needed to establish causality.


Asunto(s)
COVID-19 , Depresión , Pacientes Ambulatorios , Humanos , COVID-19/psicología , COVID-19/epidemiología , Masculino , Femenino , Depresión/epidemiología , Adulto , Pacientes Ambulatorios/psicología , Persona de Mediana Edad , Estudios Transversales , Nigeria/epidemiología , Prevalencia , SARS-CoV-2/aislamiento & purificación , Anciano , Adolescente , Gobierno Local , Adulto Joven , Pandemias
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