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Effects of three long-acting reversible contraceptive methods on HIV target cells in the human uterine cervix and peripheral blood.
No full textBackgroundHormonal contraceptives, particularly depot medroxyprogesterone acetate (DMPA), have been reported to be associated with substantially enhanced HIV acquisition; however, the biological mechanisms of this risk remain poorly understood. We aimed to investigate the effects of different hormonal contraceptives on the expression of the HIV co-receptors, CXCR4 and CCR5, on female endocervical and peripheral blood T cells.MethodsA total of 59 HIV-negative women were enrolled, including 15 initiating DMPA, 28 initiating a levonorgestrel-releasing intrauterine device (LNG-IUD) and 16 initiating an etonogestrel (ETG)-delivering vaginal ring. Peripheral blood and endocervical cytobrush specimens were collected at enrollment and 3-4 weeks after contraception initiation to analyze the expression of CXCR4 and CCR5, on CD4+ and CD8+ T cells using flow cytometry.ResultsAdministration of DMPA increased the percentages of CD4+ and CD8+ T cells expressing CCR5 in the endocervix but not in the peripheral blood. Administration of the LNG-IUD or the ETG vaginal ring did not affect the percentages of T lymphocytes expressing CXCR4 or CCR5 in the female cervix or peripheral blood.ConclusionsIncrease in the percentage of endocervical T cells expressing CCR5 upon DMPA exposure provides a plausible biological explanation for the association between DMPA use and an elevated risk of HIV infection
Intraoperative Neurophysiological Monitoring in Spine Deformity Surgery
Get PDFAlthough the incidence of neurologic injury in deformity surgery is low, the repercussions are devastating; therefore, every measure available should be adopted to minimize that risk. Advances in instrumentation have been paralleled by the development and improved understanding of intraoperative neurophysiological monitoring which enables lower morbidity in increasingly complex surgeries. Currently, multimodality intraoperative neurophysiological monitoring includes somatosensory-evoked potentials, transcranial motor–evoked potentials, triggered electromyographic stimulation, and mixed neurogenic evoked potentials. The combination of these monitoring modalities provides the greatest sensitivity in detecting impending neurologic compromise during deformity surgery
HALLUX PROXIMAL PHALANX FRACTURE IN ADULTS: AN OVERLOOKED DIAGNOSIS.
No full textObjectivesTo describe the surgical treatment of fractures that involves the hallux interphalangeal joint, current indications and management options.Methodswe performed a literature review of relevant clinical studies in multiple databases, including PubMed, MedLine and Scopus, from January 1989 to October 2020.ResultsThere is consensus for surgical treatment of intra-articular fractures with a deviation greater than 2 mm, metadiaphyseal fractures with malrotation and/or malangulation, open fractures and unstable fractures.ConclusionThe use of more rigid implants allow alignment maintenance during healing process and lower risk of reduction loss. Valgus deformity and interphalangeal joint osteoarthritis are possible complications that must be avoided. Level of Evidence III, Systematic review of Level III studies.</i
Read like a Radiologist: Cancer Detection using Multi-view Correspondence in Digital Breast Tomosynthesis
No full textBreast cancer is the second leading cause of cancer death among women, with approximately 43,780 related deaths annually. Effective screening programs are essential in reducing mortality rates by providing early diagnosis and treatment. Historically, mammography has been the most reliable screening method, significantly dropping the per capita mortality rate since its widespread adoption in the 1980s. However, the increasing workload of approximately 40 million mammography procedures conducted annually in the US poses a significant challenge to the healthcare system. This leads to reports of high rates of burnout among breast radiologists, which can decrease reading accuracy and patient care quality. Therefore, there is a need to improve the existing breast cancer screening workflow to address this challenge.CAD algorithms have been developed to reduce radiologists' workload and address burnout. However, existing single-view CAD systems often have limited cancer detection performance as well as clinical impact. To overcome this limitation, we collaborated with iCAD (Nashua, NA) to develop a novel Computer-Aided-Detection (CAD) framework for digital breast tomosynthesis (DBT) that mimics the multi-view mammography reading practice used by breast radiologists. As of May 2023, the algorithm is under the initial submission for FDA 510(k) approval.
This dissertation introduces a multi-view DBT lesion detection framework consisting of four chapters. Chapter 1 highlights the challenges of breast cancer screening and the necessity for an enhanced DBT CAD algorithm. Chapter 2 presents the single-view detection pipeline, while chapter 3 proposes the ipsilateral refinement concept that improves cancer lesion detection performance. Chapter 4 outlines the temporal matching concept that enhances system-level performance by integrating lesion temporal growth information. Chapter 5 showcases a few additional studies that supported the development of the multi-view lesion detection algorithm.Our design uses cascaded task-specific models for each of our proposed modules, enabling intermediate reasoning of the multi-view reading steps. This approach allows the radiologist to inspect the output generated by the CAD system and verify the reasoning behind the system's decision, providing an additional layer of validation for complex high-stakes decisions.</p
Supporting Women Vanilla Farmers in Madagascar: The Promise of VSLAs and Alternative Livelihoods
No full textTo examine how to strengthen the income security and overall resilience of women vanilla farmers, I ask: How can Duke Lemur Center (DLC)-SAVA Conservation better support the livelihoods of local women vanilla farmers in Ambodivoara, Madagascar, through training in alternative livelihoods? What is the economic, social, and environmental potential for the establishment of village savings and loans associations (VSLAs) for women vanilla farmers? Drawing from three months of field research in Madagascar, I offer policy recommendations to answer these questions
Use of the consolidated framework for implementation research in a mixed methods evaluation of the EQUIPPED medication safety program in four academic health system emergency departments.
No full textBackgroundEnhancing Quality of Prescribing Practices for Older Adults Discharged from the Emergency Department (EQUIPPED) is an effective quality improvement program initially designed in the Veterans Administration (VA) health care system to reduce potentially inappropriate medication prescribing for adults aged 65 years and older. This study examined factors that influence implementation of EQUIPPED in EDs from four distinct, non-VA academic health systems using a convergent mixed methods design that operationalized the Consolidated Framework for Implementation Research (CFIR). Fidelity of delivery served as the primary implementation outcome.Materials and methodsFour EDs implemented EQUIPPED sequentially from 2017 to 2021. Using program records, we scored each ED on a 12-point fidelity index calculated by adding the scores (1-3) for each of four components of the EQUIPPED program: provider receipt of didactic education, one-on-one academic detailing, monthly provider feedback reports, and use of order sets. We comparatively analyzed qualitative data from focus groups with each of the four implementation teams (n = 22) and data from CFIR-based surveys of ED providers (108/234, response rate of 46.2%) to identify CFIR constructs that distinguished EDs with higher vs. lower levels of implementation.ResultsOverall, three sites demonstrated higher levels of implementation (scoring 8-9 of 12) and one ED exhibited a lower level (scoring 5 of 12). Two constructs distinguished between levels of implementation as measured through both quantitative and qualitative approaches: patient needs and resources, and organizational culture. Implementation climate distinguished level of implementation in the qualitative analysis only. Networks and communication, and leadership engagement distinguished level of implementation in the quantitative analysis only.DiscussionUsing CFIR, we demonstrate how a range of factors influence a critical implementation outcome and build an evidence-based approach on how to prime an organizational setting, such as an academic health system ED, for successful implementation.ConclusionThis study provides insights into implementation of evidence-informed programs targeting medication safety in ED settings and serves as a potential model for how to integrate theory-based qualitative and quantitative methods in implementation studies
Dysphagia following combined anterior-posterior cervical spine surgeries.
No full textObjectThis study was undertaken to evaluate the incidence of and risk factors associated with the development of dysphagia following same-day combined anterior-posterior cervical spine surgeries.MethodsThe records of 30 consecutive patients who underwent same-day combined anterior-posterior cervical spine surgery were reviewed. The presence of dysphagia was assessed by a formalized screening protocol using history/clinical presentation and a bedside swallowing test, followed by formal evaluation by speech and language pathologists and/or fiberoptic endoscopic evaluation of swallowing/modified barium swallow when necessary. Age, sex, previous cervical surgeries, diagnoses, duration of procedure, specific vertebral levels and number of levels operated on, degree of sagittal curve correction, use of anterior plate, estimated blood loss, use of recombinant human bone morphogenetic protein-2 (rhBMP-2), and length of hospital stay following procedures were analyzed.ResultsIn the immediate postoperative period, 13 patients (43.3%) developed dysphagia. Outpatient follow-up data were available for 11 patients with dysphagia, and within this subset, all cases of dysphagia resolved subjectively within 12 months following surgery. The mean numbers of anterior levels surgically treated in patients with and without dysphagia were 5.1 and 4.0, respectively (p = 0.004). All patients (100%) with dysphagia had an anterior procedure that extended above C-4, compared with 58.8% of patients without dysphagia (p = 0.010). Patients with dysphagia had significantly greater mean correction of C2-7 lordosis than patients without dysphagia (p = 0.020). The postoperative sagittal occiput-C2 angle and the change in this angle were not significantly associated with the occurrence of dysphagia (p = 0.530 and p = 0.711, respectively). Patients with postoperative dysphagia had significantly longer hospital stays than those who did not develop dysphagia (p = 0.004). No other significant difference between the dysphagia and no-dysphagia groups was identified; differences with respect to history of previous anterior cervical surgery (p = 0.141), use of an anterior plate (p = 0.613), and mean length of anterior cervical operative time (p = 0.541) were not significant.ConclusionsThe incidence of dysphagia following combined anterior-posterior cervical surgery in this study was comparable to that of previous reports. The risk factors for dysphagia that were identified in this study were increased number of anterior levels exposed, anterior surgery that extended above C-4, and increased surgical correction of C2-7 lordosis
Structural, Biological, and Psychosocial Determinants of Frailty in Community-dwelling Older Adults in the U.S.
No full textFrailty is a common geriatric syndrome in older adults associated with a host of adverse outcomes. Frailty disproportionately affects women, older adults who identify as Hispanic, non-Hispanic Black, and those with less income in the US. The underlying mechanism contributing to frailty disparities across structural social determinants of health (gender, race, ethnicity, and education) is poorly understood. This study aimed to elucidate whether these structural social determinants operate through intermediary biological factors (cardiometabolic) and psychosocial stressors and influence frailty in community-dwelling older adults in the US. The World Health Organization’s conceptual framework of action on social determinants of health (CSDH) underpins this study. The CSDH framework claims that structural social determinants of health shape social hierarchy contingent on individuals’ gender, race, ethnicity, and education, which may offer structural advantages and disadvantages. Individuals’ ranking in the social hierarchy may differentially expose them to intermediary health-promoting or damaging factors leading to disparate health outcomes. This study hypothesized that structural social determinants (gender, race, ethnicity, and education) are associated with disproportionate exposure to intermediary biological cardiometabolic factors and psychosocial stressors, which may be related to the differential frailty risk.
This cross-sectional, descriptive, correlational study is the secondary analysis of the existing data from the Health and Retirement Study (HRS). This study involved approximately 8000 older adults (65 years and above) who met the eligibility criteria for the examination of physical, cardiometabolic biomarker measurements, and psychosocial information in 2006 or 2008. We used the Fried phenotype to classify frailty on the basis of the presence of at least three features, such as poor grip strength, slow gait speed, fatigue, weight loss, and low physical activity. We used clinical cutoffs to dichotomize the presence and absence of seven cardiometabolic factors (elevated blood pressure, sugar, C-reactive protein, total cholesterol; obesity, abdominal obesity, and low high-density lipoprotein). Based on empirical studies, we dichotomized six psychosocial factors (loneliness, financial strain, perceived everyday discrimination, subjective social status, poor neighborhood, and experience of traumatic life events) originating from multiple life domains into high and low psychosocial stressors.
We used latent class analysis to identify subgroups of older adults with distinct combinations of cardiometabolic (typologies). Path analysis (a series of logistic regressions) was used to examine the structural determinants and cardiometabolic relationships with frailty and explore whether cardiometabolic typologies mediate the relationship between structural determinants and frailty. Our results further confirm that frailty disparities persist. Female, older adults who identify as Hispanic, non-Hispanic Black, and those with less education had a higher frailty risk relative to male, non-Hispanic White older adults, and those with high education. Structural social determinants were significantly related to latent subgroups of older adults with distinct cardiometabolic typologies. The members of the insulin resistance subgroup were more likely to be female, they were more likely identify as non-Hispanic Black, and were college non-graduates. The members of the hypertensive dyslipidemia were more likely to identify as non-Hispanic other minorities and were high school graduates, and the members in the hypertensive subgroup were more likely to be male and college graduates. The frailty risk differed among these latent subgroups of older adults, and the insulin resistance subgroup had a higher frailty risk than hypertensive dyslipidemia and hypertensive subgroups. In contrast, the frailty risk did not differ in the latter two subgroups. However, cardiometabolic typologies did not mediate the relationship between structural social determinants and frailty.
Cumulative psychosocial stress was used to assess co-occurring psychosocial stress stemming from multiple life domains. We measured cumulative psychosocial stress by counting six dichotomized psychosocial stressors originating from multiple life domains. Path analysis (a series of multivariable regression models) was used to examine structural social determinants and cumulative psychosocial stress relationships with frailty and determine the mediating role of cumulative psychosocial stress between structural social determinants and frailty. Older adults who identified as Hispanic, non-Hispanic Black, non-Hispanic other ethnic minorities, and those with less education were more likely to experience greater cumulative psychosocial stress. Greater cumulative psychosocial stress was associated with higher frailty risk; however, it did not mediate the relationship between structural social determinants and frailty.
Our results solidify the multifactorial nature of frailty. Structural social determinants, cardiometabolic typologies, and cumulative psychosocial stress independently contributed to frailty. Surprisingly, cardiometabolic typologies and cumulative psychosocial stress did not mediate the relationships between structural social determinants and frailty. Our study sets the foundation for exploring other biological and psychosocial stressors contributing to frailty and examining their mediating roles.
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Does vertebral level of pedicle subtraction osteotomy correlate with degree of spinopelvic parameter correction?
No full textObjectPedicle subtraction osteotomy (PSO) is a spinal realignment technique that may be used to correct sagittal spinal imbalance. Theoretically, the level and degree of resection via a PSO should impact the degree of sagittal plane correction in the setting of deformity. However, the quantitative effect of PSO level and focal angular change on postoperative spinopelvic parameters has not been well described. The purpose of this study is to analyze the relationship between the level/degree of PSO and changes in global sagittal balance and spinopelvic parameters.MethodsIn this multicenter retrospective study, 70 patients (54 women and 16 men) underwent lumbar PSO surgery for spinal imbalance. Preoperative and postoperative free-standing sagittal radiographs were obtained and analyzed by regional curves (lumbar, thoracic, and thoracolumbar), pelvic parameters (pelvic incidence and pelvic tilt [PT]) and global balance (sagittal vertical axis [SVA] and T-1 spinopelvic inclination). Correlations between PSO parameters (level and degree of change in angle between the 2 adjacent vertebrae) and spinopelvic measurements were analyzed.ResultsPedicle subtraction osteotomy distribution by level and degree of correction was as follows: L-1 (6 patients, 24°), L-2 (15 patients, 24°), L-3 (29 patients, 25°), and L-4 (20 patients, 22°). There was no significant difference in the focal correction achieved by PSO by level. All patients demonstrated changes in preoperative to postoperative parameters including increased lumbar lordosis (from 20° to 49°, p ConclusionsThe degree of PSO resection correlates more with spinopelvic parameters (lumbar lordosis, thoracic kyphosis, PT, and sacral slope) than PSO level. More importantly, PSO level impacts postoperative PT correction but not SVA
A Case of Plasmodium falciparum Malaria in a Man 6 Months after Visiting a Malaria-Endemic Region
No full textUnlike other malaria-causing species of the genus Plasmodium, Plasmodium falciparum normally manifests symptoms of malaria within weeks of exposure. We report the unusual case of symptomatic malaria in a previously healthy individual 6 months after staying in an endemic region. In addition, potential causes for delayed presentation of P falciparum are reviewed. This case shows that P falciparum can have a prolonged incubation period and raises questions as to causes of delayed presentation and where parasites reside before symptoms manifest. Copyright © 2012 by Lippincott Williams & Wilkins