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1.
Proc Natl Acad Sci U S A ; 121(11): e2211711120, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38408214

RESUMEN

Today, relatively warm Circumpolar Deep Water is melting Thwaites Glacier at the base of its ice shelf and at the grounding zone, contributing to significant ice retreat. Accelerating ice loss has been observed since the 1970s; however, it is unclear when this phase of significant melting initiated. We analyzed the marine sedimentary record to reconstruct Thwaites Glacier's history from the early Holocene to present. Marine geophysical surveys were carried out along the floating ice-shelf margin to identify core locations from various geomorphic settings. We use sedimentological data and physical properties to define sedimentary facies at seven core sites. Glaciomarine sediment deposits reveal that the grounded ice in the Amundsen Sea Embayment had already retreated to within ~45 km of the modern grounding zone prior to ca. 9,400 y ago. Sediments deposited within the past 100+ y record abrupt changes in environmental conditions. On seafloor highs, these shifts document ice-shelf thinning initiating at least as early as the 1940s. Sediments recovered from deep basins reflect a transition from ice proximal to slightly more distal conditions, suggesting ongoing grounding-zone retreat since the 1950s. The timing of ice-shelf unpinning from the seafloor for Thwaites Glacier coincides with similar records from neighboring Pine Island Glacier. Our work provides robust new evidence that glacier retreat in the Amundsen Sea was initiated in the mid-twentieth century, likely associated with climate variability.

2.
Acta Neuropathol ; 148(1): 18, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39141121

RESUMEN

Lewy body disorders are heterogeneous neurological conditions defined by intracellular inclusions composed of misshapen α-synuclein protein aggregates. Although α-synuclein aggregates are only one component of inclusions and not strictly coupled to neurodegeneration, evidence suggests they seed the propagation of Lewy pathology within and across cells. Genetic mutations, genomic multiplications, and sequence polymorphisms of the gene encoding α-synuclein are also causally linked to Lewy body disease. In nonfamilial cases of Lewy body disease, the disease trigger remains unidentified but may range from industrial/agricultural toxicants and natural sources of poisons to microbial pathogens. Perhaps due to these peripheral exposures, Lewy inclusions appear at early disease stages in brain regions connected with cranial nerves I and X, which interface with inhaled and ingested environmental elements in the nasal or gastrointestinal cavities. Irrespective of its identity, a stealthy disease trigger most likely shifts soluble α-synuclein (directly or indirectly) into insoluble, cross-ß-sheet aggregates. Indeed, ß-sheet-rich self-replicating α-synuclein multimers reside in patient plasma, cerebrospinal fluid, and other tissues, and can be subjected to α-synuclein seed amplification assays. Thus, clinicians should be able to capitalize on α-synuclein seed amplification assays to stratify patients into potential responders versus non-responders in future clinical trials of α-synuclein targeted therapies. Here, we briefly review the current understanding of α-synuclein in Lewy body disease and speculate on pathophysiological processes underlying the potential transmission of α-synucleinopathy across the neuraxis.


Asunto(s)
Enfermedad por Cuerpos de Lewy , alfa-Sinucleína , Humanos , Enfermedad por Cuerpos de Lewy/patología , Enfermedad por Cuerpos de Lewy/metabolismo , alfa-Sinucleína/metabolismo , Animales , Encéfalo/patología , Encéfalo/metabolismo , Cuerpos de Lewy/patología , Cuerpos de Lewy/metabolismo
3.
Dig Dis Sci ; 69(7): 2586-2594, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38684633

RESUMEN

BACKGROUND: Individuals with inflammatory bowel disease (IBD) who lack traditional cardiovascular disease (CVD) risk factors, such as young females, are observed to experience adverse CVD outcomes. Whether women with IBD have increased CVD risk after the menopause transition is unclear. METHODS: We conducted a survival analysis of Women's Health Initiative (WHI) participants and excluded those with missing IBD diagnosis, model covariate data, follow-up data, or a baseline history of the following CVD outcomes: coronary heart disease (CHD), ischemic stroke, venous thromboembolism (VTE), peripheral arterial disease (PAD). Risk of outcomes between IBD and non-IBD women was performed using Cox proportional hazard models, stratified by WHI trial and follow-up. Models were adjusted for age, socio-demographics, comorbidities (e.g., hypertension, diabetes, hypercholesterolemia, etc.), family history, and lifestyle factors (e.g., smoking, alcohol, physical activity, body mass index, etc.). RESULTS: Of 134,022 WHI participants meeting inclusion criteria, 1367 (1.0%) reported IBD at baseline. Mean baseline age was 63.4 years. After adjusting for age and other confounders, no significant difference was observed between IBD and non-IBD women for the risk of CHD (HR 0.96, 95% CI 0.73-1.24), VTE (HR 1.11, 95% CI 0.81-1.52) or PAD (HR 0.64, 95% CI 0.28-1.42). After adjusting for age, risk of ischemic stroke was significantly higher (HR 1.41, 95% CI 1.06-1.88) in IBD than non-IBD women. With further adjustment, the excess risk of ischemic stroke among IBD women was attenuated and no longer statistically significant (HR 1.31, 95% CI 0.98-1.76). CONCLUSIONS: Among postmenopausal women with IBD, risk of ischemic stroke may be higher than in non-IBD women.


Asunto(s)
Enfermedades Cardiovasculares , Enfermedades Inflamatorias del Intestino , Posmenopausia , Humanos , Femenino , Persona de Mediana Edad , Enfermedades Inflamatorias del Intestino/complicaciones , Enfermedades Inflamatorias del Intestino/epidemiología , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/etiología , Anciano , Modelos de Riesgos Proporcionales , Accidente Cerebrovascular Isquémico/epidemiología , Accidente Cerebrovascular Isquémico/etiología , Factores de Riesgo , Estados Unidos/epidemiología , Factores de Riesgo de Enfermedad Cardiaca , Enfermedad Coronaria/epidemiología
4.
Neurobiol Dis ; 184: 106196, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37315905

RESUMEN

Reactive microglia are observed with aging and in Lewy body disorders, including within the olfactory bulb of men with Parkinson's disease. However, the functional impact of microglia in these disorders is still debated. Resetting these reactive cells by a brief dietary pulse of the colony-stimulating factor 1 receptor (CSF1R) inhibitor PLX5622 may hold therapeutic potential against Lewy-related pathologies. To our knowledge, withdrawal of PLX5622 after short-term exposure has not been tested in the preformed α-synuclein fibril (PFF) model, including in aged mice of both sexes. Compared to aged female mice, we report that aged males on the control diet showed higher numbers of phosphorylated α-synuclein+ inclusions in the limbic rhinencephalon after PFFs were injected in the posterior olfactory bulb. However, aged females displayed larger inclusion sizes compared to males. Short-term (14-day) dietary exposure to PLX5622 followed by control chow reduced inclusion numbers and levels of insoluble α-synuclein in aged males-but not females-and unexpectedly raised inclusion sizes in both sexes. Transient delivery of PLX5622 also improved spatial reference memory in PFF-infused aged mice, as evidenced by an increase in novel arm entries in a Y-maze. Superior memory was positively correlated with inclusion sizes but negatively correlated with inclusion numbers. Although we caution that PLX5622 delivery must be tested further in models of α-synucleinopathy, our data suggest that larger-sized-but fewer-α-synucleinopathic structures are associated with better neurological outcomes in PFF-infused aged mice.


Asunto(s)
Enfermedad por Cuerpos de Lewy , Enfermedad de Parkinson , Sinucleinopatías , Masculino , Femenino , Ratones , Animales , alfa-Sinucleína , Sinucleinopatías/patología , Enfermedad por Cuerpos de Lewy/patología , Enfermedad de Parkinson/patología
5.
Plant Physiol ; 189(2): 906-921, 2022 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-35166829

RESUMEN

Nannochloropsis oceanica, like other stramenopile microalgae, is rich in long-chain polyunsaturated fatty acids (LC-PUFAs) such as eicosapentaenoic acid (EPA). We observed that fatty acid desaturases (FADs) involved in LC-PUFA biosynthesis were among the strongest blue light-induced genes in N. oceanica CCMP1779. Blue light was also necessary for maintaining LC-PUFA levels in CCMP1779 cells, and growth under red light led to a reduction in EPA content. Aureochromes are stramenopile-specific proteins that contain a light-oxygen-voltage (LOV)-sensing domain that associates with a flavin mononucleotide and is able to sense blue light. These proteins also contain a basic leucine zipper DNA-binding motif and can act as blue light-regulated transcription factors by associating with an E-box like motif, which we found enriched in the promoters of blue light-induced genes. We demonstrated that, in vitro, two CCMP1779 aureochromes were able to absorb blue light. Moreover, the loss or reduction of the expression of any of the three aureochrome genes led to a decrease in the blue light-specific induction of several FADs in CCMP1779. EPA content was also significantly reduced in NoAUREO2 and NoAUREO4 mutants. Taken together, our results indicate that aureochromes mediate blue light-dependent regulation of LC-PUFA content in N. oceanica CCMP1779 cells.


Asunto(s)
Microalgas , Estramenopilos , Ácido Eicosapentaenoico/metabolismo , Ácido Graso Desaturasas/genética , Ácido Graso Desaturasas/metabolismo , Ácidos Grasos/metabolismo , Ácidos Grasos Insaturados/metabolismo , Luz , Microalgas/genética , Microalgas/metabolismo , Estramenopilos/metabolismo
6.
Rev Cardiovasc Med ; 24(12): 350, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39077078

RESUMEN

Although great progress has been made in the diagnostic and treatment options for dyslipidemias, unawareness, underdiagnosis and undertreatment of these disorders remain a significant global health concern. Growth in digital applications and newer models of care provide novel tools to improve the management of chronic conditions such as dyslipidemia. In this review, we discuss the evolving landscape of lipid management in the 21st century, current treatment gaps and possible solutions through digital health and new models of care. Our discussion begins with the history and development of value-based care and the national establishment of quality metrics for various chronic conditions. These concepts on the level of healthcare policy not only inform reimbursements but also define the standard of care. Next, we consider the advances in atherosclerotic cardiovascular disease risk score calculators as well as evolving imaging modalities. The impact and growth of digital health, ranging from telehealth visits to online platforms and mobile applications, will also be explored. We then evaluate the ways in which machine learning and artificial intelligence-driven algorithms are being utilized to address gaps in lipid management. From an organizational perspective, we trace the redesign of medical practices to incorporate a multidisciplinary team model of care, recognizing that atherosclerotic cardiovascular disease risk is multifaceted and requires a comprehensive approach. Finally, we anticipate the future of dyslipidemia management, assessing the many ways in which atherosclerotic cardiovascular disease burden can be reduced on a population-wide scale.

7.
J Public Health (Oxf) ; 45(4): 804-815, 2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-37477219

RESUMEN

BACKGROUND: Accommodations with shared washing facilities increase the risks of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection for people experiencing rough sleeping and evidence on what interventions are effective in reducing these risks needs to be understood. METHODS: Systematic review, search date 6 December 2022 with methods published a priori. Electronic searches were conducted in MEDLINE, PubMed, Cochrane Library, CINAHL and the World Health Organization (WHO) COVID-19 Database and supplemented with grey literature searches, hand searches of reference lists and publication lists of known experts. Observational, interventional and modelling studies were included; screening, data extraction and risk of bias assessment were done in duplicate and narrative analyses were conducted. RESULTS: Fourteen studies from five countries (USA, England, France, Singapore and Canada) were included. Ten studies were surveillance reports, one was an uncontrolled pilot intervention, and three were modelling studies. Only two studies were longitudinal. All studies described the effectiveness of different individual or packages of mitigation measures. CONCLUSIONS: Despite a weak evidence base, the research suggests that combined mitigation measures can help to reduce SARS-CoV-2 transmission but are unlikely to prevent outbreaks entirely. Evidence suggests that community prevalence may modify the effectiveness of mitigation measures. More longitudinal research is needed. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42021292803.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , COVID-19/prevención & control , SARS-CoV-2 , Sesgo , Brotes de Enfermedades , Canadá/epidemiología
8.
Ann Surg Oncol ; 28(11): 6705-6713, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33683525

RESUMEN

BACKGROUND: Ovarian cancer with miliary disease spread is an aggressive phenotype lacking targeted management strategies. We sought to determine whether adjuvant intravenous/intraperitoneal (IV/IP) chemotherapy is beneficial in this disease setting. METHODS: Patient/tumor characteristics and survival data of patients with stage IIIC epithelial ovarian cancer who underwent optimal primary debulking surgery from 01/2010 to 11/2014 were abstracted from records. Chi-square and Mann-Whitney U tests were used to compare categorical and continuous variables. The Kaplan-Meier method was used to estimate survival curves, and outcomes were compared using log-rank tests. Factors significant on univariate analysis were combined into multivariate logistic regression survival models. RESULTS: Among 90 patients with miliary disease spread, 41 (46%) received IV/IP chemotherapy and 49 (54%) received IV chemotherapy. IV/IP chemotherapy, compared with IV chemotherapy, resulted in improved progression-free survival (PFS; 23.0 versus 12.0 months; p = 0.0002) and overall survival (OS; 52 versus 36 months; p = 0.002) in patients with miliary disease. Among 78 patients with nonmiliary disease spread, 23 (29%) underwent IV/IP chemotherapy and 55 (71%) underwent IV chemotherapy. There was no PFS or OS benefit associated with IV/IP chemotherapy over IV chemotherapy in these patients. On multivariate analysis, IV/IP chemotherapy was associated with improved PFS (HR, 0.28; 95% CI 0.15-0.53) and OS (HR, 0.33; 95% CI 0.18-0.61) in patients with miliary disease compared with those with nonmiliary disease (PFS [HR, 1.53; 95% CI 0.74-3.19]; OS [HR, 1.47; 95% CI 0.70-3.09]). CONCLUSIONS: Adjuvant IV/IP chemotherapy was associated with oncologic benefit in miliary disease spread. This survival benefit was not observed in nonmiliary disease.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias Ováricas , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma Epitelial de Ovario/tratamiento farmacológico , Carcinoma Epitelial de Ovario/patología , Quimioterapia Adyuvante , Procedimientos Quirúrgicos de Citorreducción , Supervivencia sin Enfermedad , Femenino , Humanos , Infusiones Parenterales , Estadificación de Neoplasias , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/patología , Estudios Retrospectivos
9.
JAMA ; 325(14): 1443-1463, 2021 04 13.
Artículo en Inglés | MEDLINE | ID: mdl-33847712

RESUMEN

Importance: Low serum vitamin D levels have been associated with adverse clinical outcomes; identifying and treating deficiency may improve outcomes. Objective: To review the evidence about screening for vitamin D deficiency in adults. Data Sources: PubMed, EMBASE, the Cochrane Library, and trial registries through March 12, 2020; bibliographies from retrieved articles, outside experts, and surveillance of the literature through November 30, 2020. Study Selection: Fair- or good-quality, English-language randomized clinical trials (RCTs) of screening with serum 25-hydroxyvitamin D (25[OH]D) compared with no screening, or treatment with vitamin D (with or without calcium) compared with placebo or no treatment conducted in nonpregnant adults; nonrandomized controlled intervention studies for harms only. Treatment was limited to studies enrolling or analyzing participants with low serum vitamin D levels. Data Extraction and Synthesis: Two reviewers assessed titles/abstracts and full-text articles, extracted data, and assessed study quality; when at least 3 similar studies were available, meta-analyses were conducted. Main Outcomes and Measures: Mortality, incident fractures, falls, diabetes, cardiovascular events, cancer, depression, physical functioning, and infection. Results: Forty-six studies (N = 16 205) (77 publications) were included. No studies directly evaluated the health benefits or harms of screening. Among community-dwelling populations, treatment was not significantly associated with mortality (pooled absolute risk difference [ARD], 0.3% [95% CI, -0.6% to 1.1%]; 8 RCTs, n = 2006), any fractures (pooled ARD, -0.3% [95% CI, -2.1% to 1.6%]; 6 RCTs, n = 2186), incidence of diabetes (pooled ARD, 0.1% [95% CI, -1.3% to 1.6%]; 5 RCTs, n = 3356), incidence of cardiovascular disease (2 RCTs; hazard ratio, 1.00 [95% CI, 0.74 to 1.35] and 1.09 [95% CI, 0.68 to 1.76]), incidence of cancer (2 RCTs; hazard ratio, 0.97 [95% CI, 0.68 to 1.39] and 1.01 [95% CI, 0.65 to 1.58], or depression (3 RCTs, various measures reported). The pooled ARD for incidence of participants with 1 or more falls was -4.3% (95% CI, -11.6% to 2.9%; 6 RCTs). The evidence was mixed for the effect of treatment on physical functioning (2 RCTs) and limited for the effect on infection (1 RCT). The incidence of adverse events and kidney stones was similar between treatment and control groups. Conclusions and Relevance: No studies evaluated the direct benefits or harms of screening for vitamin D deficiency. Among asymptomatic, community-dwelling populations with low vitamin D levels, the evidence suggests that treatment with vitamin D has no effect on mortality or the incidence of fractures, falls, depression, diabetes, cardiovascular disease, cancer, or adverse events. The evidence is inconclusive about the effect of treatment on physical functioning and infection.


Asunto(s)
Colecalciferol/uso terapéutico , Tamizaje Masivo , Deficiencia de Vitamina D/diagnóstico , Vitamina D/sangre , Vitaminas/uso terapéutico , Accidentes por Caídas , Adulto , Enfermedades Asintomáticas , Fracturas Óseas/prevención & control , Humanos , Tamizaje Masivo/efectos adversos , Guías de Práctica Clínica como Asunto , Vitamina D/análogos & derivados , Deficiencia de Vitamina D/sangre , Deficiencia de Vitamina D/complicaciones , Deficiencia de Vitamina D/mortalidad
10.
J Gen Intern Med ; 35(3): 855-864, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31713029

RESUMEN

BACKGROUND: Lumbar radiculopathy is characterized by radiating pain with or without motor weakness or sensory disturbances; the point prevalence ranges from 1.6 to 13.4%. The objective of this review was to determine the efficacy, safety, and cost of surgical versus nonsurgical management of symptomatic lumbar radiculopathy in adults. METHODS: We searched PubMed from January 1, 2007, to April 10, 2019 with hand searches of systematic reviews for studies prior to 2007. One reviewer extracted data and a second checked for accuracy. Two reviewers completed independent risk of bias and strength of evidence ratings. RESULTS: We included seven RCTs (N = 1158) and three cost-effectiveness analysis. Surgery reduced leg pain by 6 to 26 points more than nonsurgical interventions as measured on a 0- to 100-point visual analog scale of pain at up to 26 weeks follow-up; differences between groups did not persist at 1 year or later. The evidence was somewhat mixed for function and disability in follow-up through 26 weeks (standardized mean difference [SMD] - 0.16 (95% CI, - 0.30 to - 0.03); minimal differences were observed at 2 years (SMD - 0.06 (95% CI, - 0.20 to 0.07). There were similar improvements in quality of life, neurologic symptoms, and return to work. No surgical deaths occurred and surgical morbidity was infrequent. The incidence of reoperations ranged from 0 to 10%. The average cost per quality-adjusted life year gained from a healthcare payor perspective ranged from $51,156 to $83,322 for surgery compared to nonsurgical interventions. DISCUSSION: Most findings are based on a body of RCT evidence graded as low to very low certainty. Compared with nonsurgical interventions, surgery probably reduces pain and improves function in the short- and medium-term, but this difference does not persist in the long-term. Although surgery appears to be safe, it may or may not be cost-effective depending on a decision maker's willingness to pay threshold.


Asunto(s)
Radiculopatía , Adulto , Humanos , Dolor , Dimensión del Dolor , Calidad de Vida , Radiculopatía/cirugía
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