Dendritic spines are micron-sized membrane protrusions receiving most excitatory synaptic inputs in the mammalian brain. Spines form and grow during long-term potentiation (LTP) of synaptic strength. ...However, the source of membrane for spine formation and enlargement is unknown. Here we report that membrane trafficking from recycling endosomes is required for the growth and maintenance of spines. Using live-cell imaging and serial section electron microscopy, we demonstrate that LTP-inducing stimuli promote the mobilization of recycling endosomes and vesicles into spines. Preventing recycling endosomal transport abolishes LTP-induced spine formation. Using a pH-sensitive recycling cargo, we show that exocytosis from recycling endosomes occurs locally in spines, is triggered by activation of synaptic NMDA receptors, and occurs concurrently with spine enlargement. Thus, recycling endosomes provide membrane for activity-dependent spine growth and remodeling, defining a novel membrane trafficking mechanism for spine morphological plasticity and providing a mechanistic link between structural and functional plasticity during LTP.
An approach combining signal detection theory and precise 3D reconstructions from serial section electron microscopy (3DEM) was used to investigate synaptic plasticity and information storage ...capacity at medial perforant path synapses in adult hippocampal dentate gyrus in vivo. Induction of long-term potentiation (LTP) markedly increased the frequencies of both small and large spines measured 30 minutes later. This bidirectional expansion resulted in heterosynaptic counterbalancing of total synaptic area per unit length of granule cell dendrite. Control hemispheres exhibited 6.5 distinct spine sizes for 2.7 bits of storage capacity while LTP resulted in 12.9 distinct spine sizes (3.7 bits). In contrast, control hippocampal CA1 synapses exhibited 4.7 bits with much greater synaptic precision than either control or potentiated dentate gyrus synapses. Thus, synaptic plasticity altered total capacity, yet hippocampal subregions differed dramatically in their synaptic information storage capacity, reflecting their diverse functions and activation histories.
Coronary artery anomalies and their potential sequelae are not well studied in association with stillbirth. Herein, we report the autopsy findings in two term stillborn fetuses with coronary artery ...anomalies. Both fetuses showed identical findings consisting of an abnormal origin of the left coronary artery from the right sinus of Valsalva and an interarterial course of the left coronary artery. Histologic vascular and myocardial changes were also present. These coronary artery findings are associated with sudden death in adults and neonates, and therefore, their potential to be a cause and/or contributor to fetal death is suspected.
This study determines the prevalence and associated correlates of people unaware of their diabetic retinopathy diagnosis in the U.S.
Participants unaware of diabetic retinopathy from the National ...Health and Nutrition Examination Survey from 2005 to 2008 were identified. The prevalence of those unaware of their diabetic retinopathy diagnosis was determined. Descriptive statistics and logistic regression were used to determine correlates associated with being unaware of one's diabetic retinopathy diagnosis (completed in 2018‒2020).
Among 5,563 participants aged ≥40 years who underwent fundus photography, the prevalence of those unaware of their diabetic retinopathy diagnosis was 10.6% (9.8 million). This included 23.1% of those with self-reported diabetes (2.9 million) and 6.8% of those who reported not having diabetes (6.9 million). Among participants reporting diabetes with photographic evidence of retinopathy, 70.1% were unaware. Among individuals with self-reported diabetes, correlates of being unaware of one's diabetic retinopathy diagnosis included diabetes diaganosis for ≥10 years (OR=3.15, 95% CI=1.78, 5.56), HbA1c ≥6.5% (OR=2.92, 95% CI=1.65, 5.18), and treatment with insulin only (OR=4.04, 95% CI=1.43, 11.39). Self-reported hypertension was associated with decreased odds of undiagnosed diabetic retinopathy (OR=0.48, 95% CI=0.28, 0.82). Among those without self-reported diabetes, correlates of being unaware of diabetic retinopathy included older age (OR=1.02, 95% CI=1.01, 1.04), male sex (OR=1.83, 95% CI=1.31, 2.56), Black race (OR=1.81, 95% CI=1.12, 2.92), Hispanic race/ethnicity (OR=1.60, 95% CI=1.14, 2.25), elevated blood pressure (OR=1.54, 95% CI=1.23, 1.93), current smoking (OR=1.74, 95% CI=1.21, 2.51), and history of stroke (OR=2.20, 95% CI=1.06, 4.58).
A substantial proportion of individuals with diabetic retinopathy are unaware of the diagnosis. These data provide a path toward refining efforts to diagnose and treat diabetic retinopathy to decrease the burden of preventable blindness.
Abstract Background Streptococcus pneumoniae continues to cause a variety of common clinical syndromes, despite vaccination programs for both adults and children. The total U.S. burden of ...pneumococcal disease is unknown. Methods We constructed a decision tree-based model to estimate U.S. healthcare utilization and costs of pneumococcal disease in 2004. Data were obtained from the 2004–2005 National (Hospital) Ambulatory Medical Care Surveys (outpatient visits, antibiotics) and the National Hospital Discharge Survey (hospitalization rates), and CDC surveillance data. Other assumptions regarding the incidence of each syndrome due to pneumococcus, expected health outcomes, and healthcare utilization were derived from literature and expert opinion. Healthcare and time costs used 2007 dollars. Results We estimate that, in 2004, pneumococcal disease caused 4.0 million illness episodes, 22,000 deaths, 445,000 hospitalizations, 774,000 emergency department visits, 5.0 million outpatient visits, and 4.1 million outpatient antibiotic prescriptions. Direct medical costs totaled $3.5 billion. Pneumonia (866,000 cases) accounted for 22% of all cases and 72% of pneumococcal costs. In contrast, acute otitis media and sinusitis (1.5 million cases each) comprised 75% of cases but only 16% of direct medical costs. Patients ≥65 years old, accounted for most serious cases and the majority of direct medical costs ($1.8 billion in healthcare costs annually). In this age group, pneumonia caused 242,000 hospitalizations, 1.4 million hospital days, 194,000 emergency department visits, 374,000 outpatient visits, and 16,000 deaths. However, if work loss and productivity are considered, the cost of pneumococcal disease among younger working adults (18–<50) nearly equaled those ≥65. Conclusions Pneumococcal disease remains a substantial cause of morbidity and mortality even in the era of routine pediatric and adult vaccination. Continued efforts are warranted to reduce serious pneumococcal disease, especially adult pneumonia.
Exposure to ozone has been linked to reproductive outcomes, including preterm birth. In this systematic review, we summarize published epidemiologic cohort and case-control studies examining ozone ...exposures (estimated on a continuous scale) in early pregnancy (1st and 2nd trimesters (T1, T2)) and preterm birth using ratio measures, and perform a meta-analysis to evaluate the potential relationship between them. Studies were identified by searching PubMed and Web of Science, screened according to predefined inclusion/exclusion criteria, and evaluated for study quality. We extracted study data including effect estimates, confidence limits, study location, study years, ozone exposure assessment method, and mean or median ozone concentrations. Nineteen studies were identified and included, of which 18 examined T1 exposure (17 reported effect estimates), and 15 examined T2 exposure. Random effects meta-analysis was performed in the metafor package, R 3.5.3. The pooled OR (95% CI) for a 10 ppb increase in ozone exposure in T1 was 1.06 (1.03, 1.10) with a 95% prediction interval of 0.95, 1.19; for T2 it was 1.05 (1.02, 1.08) with a 95% prediction interval of 0.95, 1.16. Effect estimates for both exposure periods showed high heterogeneity. In meta-regression analyses of study characteristics, study location (continent) explained some (~20%) heterogeneity for T1 exposure studies, but no characteristic explained a substantial amount of heterogeneity for T2 exposure studies. Increased ozone exposure during early pregnancy is associated with preterm birth across studies.
•Systematic review and meta-analysis of early pregnancy ozone and preterm birth.•Both 1st and 2nd trimester ozone exposures positively associated with preterm birth.•High heterogeneity across studies, largely not explained by study characteristics.•Similarities in study design lead to little variability in study quality.
Productivity costs of STIs reflect the value of lost time due to STI morbidity and mortality, including time spent travelling to, waiting for, and receiving STI treatment. The purpose of this study ...was to provide updated estimates of the average lifetime productivity cost for chlamydia, gonorrhea, and syphilis, per incident infection.
We adapted published decision tree models from recent studies of the lifetime medical costs of chlamydia, gonorrhea, and syphilis in the United States. For each possible outcome of infection, we applied productivity costs that we obtained based on published health economic studies. Productivity costs included the value of patient time spent to receive treatment for STIs and for related sequelae such as pelvic inflammatory disease in women. We used a human capital approach and included losses in market (paid) and non-market (unpaid) productivity. We conducted one-way sensitivity analyses and probabilistic sensitivity analyses.
The average lifetime productivity cost per infection was $28 for chlamydia in men, $205 for chlamydia in women, $37 for gonorrhea in men, $212 for gonorrhea in women, and $411 for syphilis regardless of sex, in 2023 US dollars. The estimated lifetime productivity costs of these STIs acquired in the United States in 2018 was $795 million.
These estimates of the lifetime productivity costs can help in quantifying the overall economic burden of STIs in the United States beyond just the medical cost burden and can inform cost-effectiveness analyses of STI prevention activities.
Excessive alcohol drinking has been shown to modify brain circuitry to predispose individuals for future alcohol abuse. Previous studies have implicated the central nucleus of the amygdala (CeA) as ...an important site for mediating the somatic symptoms of withdrawal and for regulating alcohol intake. In addition, recent work has established a role for both the Kappa Opioid Receptor (KOR) and its endogenous ligand dynorphin in mediating these processes. However, it is unclear whether these effects are due to dynorphin or KOR arising from within the CeA itself or other input brain regions. To directly examine the role of preprodynorphin (PDYN) and KOR expression in CeA neurons, we performed region-specific conditional knockout of these genes and assessed the effects on the Drinking in the Dark (DID) and Intermittent Access (IA) paradigms. Conditional gene knockout resulted in sex-specific responses wherein PDYN knockout decreased alcohol drinking in both male and female mice, whereas KOR knockout decreased drinking in males only. We also found that neither PDYN nor KOR knockout protected against anxiety caused by alcohol drinking. Lastly, a history of alcohol drinking did not alter synaptic transmission in PDYN neurons in the CeA of either sex, but excitability of PDYN neurons was increased in male mice only. Taken together, our findings indicate that PDYN and KOR signaling in the CeA plays an important role in regulating excessive alcohol consumption and highlight the need for future studies to examine how this is mediated through downstream effector regions.
Adolescents with conduct and substance problems ("Antisocial Substance Disorder" (ASD)) repeatedly engage in risky antisocial and drug-using behaviors. We hypothesized that, during processing of ...risky decisions and resulting rewards and punishments, brain activation would differ between abstinent ASD boys and comparison boys.
We compared 20 abstinent adolescent male patients in treatment for ASD with 20 community controls, examining rapid event-related blood-oxygen-level-dependent (BOLD) responses during functional magnetic resonance imaging. In 90 decision trials participants chose to make either a cautious response that earned one cent, or a risky response that would either gain 5 cents or lose 10 cents; odds of losing increased as the game progressed. We also examined those times when subjects experienced wins, or separately losses, from their risky choices. We contrasted decision trials against very similar comparison trials requiring no decisions, using whole-brain BOLD-response analyses of group differences, corrected for multiple comparisons. During decision-making ASD boys showed hypoactivation in numerous brain regions robustly activated by controls, including orbitofrontal and dorsolateral prefrontal cortices, anterior cingulate, basal ganglia, insula, amygdala, hippocampus, and cerebellum. While experiencing wins, ASD boys had significantly less activity than controls in anterior cingulate, temporal regions, and cerebellum, with more activity nowhere. During losses ASD boys had significantly more activity than controls in orbitofrontal cortex, dorsolateral prefrontal cortex, brain stem, and cerebellum, with less activity nowhere.
Adolescent boys with ASD had extensive neural hypoactivity during risky decision-making, coupled with decreased activity during reward and increased activity during loss. These neural patterns may underlie the dangerous, excessive, sustained risk-taking of such boys. The findings suggest that the dysphoria, reward insensitivity, and suppressed neural activity observed among older addicted persons also characterize youths early in the development of substance use disorders.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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