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51.
52.
Impaired extinction of pain-related fear memories can lead to persistent or resurging fear of pain, contributing to the development and maintenance of chronic pain conditions. The mechanisms underlying maladaptive pain-related learning and memory processes remain incompletely understood, particularly in the context of interoceptive, visceral pain. Inflammation is known to interfere with learning and memory, but its effects on the extinction of pain-related fear memories have never been tested. In a randomized, double-blind, placebo-controlled study, we assessed the impact of experimental acute inflammation on the extinction and reinstatement of conditioned visceral pain-related fear. Forty healthy male volunteers underwent differential fear conditioning with visceral pain as clinically relevant unconditioned stimulus (US). Participants then received an intravenous injection of either 0.8 ng/kg lipopolysaccharide (LPS) as inflammatory stimulus or physiological saline as placebo, and extinction training was conducted at the peak of the inflammatory response. Extinction recall and reinstatement test were performed after overnight consolidation. Results showed that visceral pain represents an effective US, eliciting pronounced conditioned pain-related fear responses. Repeated unreinforced presentation of the pain-predictive cue during extinction training resulted in full extinction of the conditioned behavioral response. However, unexpected re-exposure to the US during reinstatement test resulted in return of fear. Despite pronounced LPS-induced effects on inflammatory markers, cortisol, and negative affect, we did not find evidence that acute inflammation resulted in altered fear extinction. The findings support the notion that visceral pain-related fear learning establishes a robust aversive memory trace that remains preserved during inhibitory learning, leaving a latent vulnerability for the return of fear. Inflammation during inhibitory learning did neither weaken nor further amplify this aversive memory trace, suggesting that it is rather resistant to acute inflammation-induced effects, at least in healthy individuals with no additional vulnerability factors.  相似文献   
53.
Calorie restriction (CR) is a potent modulator of longevity in multiple species. A growing body of evidence shows that sustained periods of CR without malnutrition improves risk factors involved in the pathophysiology of type 2 diabetes, cardiovascular diseases, cancer, and neurological disorders in humans. Innovative dietary strategies such as intermittent fasting and protein restriction have recently emerged as alternative approaches that improve markers of aging. Some of these newer strategies might provide benefits for healthy aging with little to no CR and therefore, compared to traditional CR, may be easier to follow. Further to providing an update of CR studies in humans, the present narrative review appraises the influence of these contemporary dietary strategies on mechanisms posited to drive CR-induced longevity in humans, including those involving energy metabolism, oxidative damage, inflammation, glucose homeostasis, and functional changes in the neuroendocrine systems. The review also discusses the utilization of these diets for populations in the current obesogenic environment, and comments on whether current research can inform an optimal diet that attenuates aging, can be easily followed, and promises to improve longevity in humans.  相似文献   
54.
Individuals living or working in moldy buildings complain of a variety of health problems including pain, fatigue, increased anxiety, depression, and cognitive deficits. The ability of mold to cause such symptoms is controversial since no published research has examined the effects of controlled mold exposure on brain function or proposed a plausible mechanism of action. Patient symptoms following mold exposure are indistinguishable from those caused by innate immune activation following bacterial or viral exposure. We tested the hypothesis that repeated, quantified doses of both toxic and nontoxic mold stimuli would cause innate immune activation with concomitant neural effects and cognitive, emotional, and behavioral symptoms. We intranasally administered either 1) intact, toxic Stachybotrys spores; 2) extracted, nontoxic Stachybotrys spores; or 3) saline vehicle to mice. As predicted, intact spores increased interleukin-1β immunoreactivity in the hippocampus. Both spore types decreased neurogenesis and caused striking contextual memory deficits in young mice, while decreasing pain thresholds and enhancing auditory-cued memory in older mice. Nontoxic spores also increased anxiety-like behavior. Levels of hippocampal immune activation correlated with decreased neurogenesis, contextual memory deficits, and/or enhanced auditory-cued fear memory. Innate-immune activation may explain how both toxic mold and nontoxic mold skeletal elements caused cognitive and emotional dysfunction.  相似文献   
55.
56.
This study is a national cross‐sectional survey, conducted in November 2014, of 366 dental hygienists and dentists who had suspected maltreatment but did not report it to Norwegian Child Welfare Services (CWS). The aims of the present paper are to identify the reasons why public dental healthcare professionals are reluctant to report suspected child maltreatment to CWS and to determine whether there are differences in the identified barriers according to socio‐demographic variables. The questionnaire was based on earlier studies and was adapted to fit the Norwegian context. The most frequently chosen reason for not reporting was “unsure of own assessment” (90.4%). Thirteen items pertaining to not reporting were factorised into three factors of barriers. These factors were “insufficient knowledge of child maltreatment and reporting”, “fear of the consequences for oneself and the dental clinic”, and “fear of the consequences for the patient and their family”. A t test revealed that public dental healthcare personnel who had not received training on maltreatment and reporting to CWS during their professional education scored significantly higher on the barrier “insufficient knowledge of child maltreatment and reporting” than did dental personnel who had received such training. Furthermore, dental personnel with more years of experience (11+) scored higher on this barrier than did dental personnel with less experience. No other significant differences in barriers were observed. Public dental healthcare personnel have a mandatory obligation to report to CWS if they suspect child maltreatment. Despite this obligation, the present study reveals that several barriers to reporting exist. This study underscores the importance of strengthening knowledge among dental hygienists and dentists about when and how to report, both during education and in clinical practice.  相似文献   
57.

Background

Politics play a role in the dissemination of public health information, including immunization-related issues. We aim to describe relationships between HPV vaccination rates and state voting patterns during the 2016 US presidential election.

Methods

We classified each of the 50 states as either “Red” or “Blue,” based on whether a higher proportion of the state’s casted votes were for the Republican or Democratic nominee during the 2016 US presidential election. State-specific HPV, Tdap, and meningococcal vaccination rates were obtained from the 2016-National Immunization Survey-Teen. State socio-demographic factors and HPV vaccine legislation were obtained from the US Census Bureau and National Conference of State Legislatures. Vaccination rates and socio-demographic variables were compared using independent t-tests. Multiple linear regression compared vaccination rates between “Red” and “Blue” states, adjusting for percentage of both uninsured children and educational attainment.

Results

Compared to “Blue” states, “Red” states had significantly lower unadjusted HPV vaccine series initiation (56% vs 66%, p?<?0.05) and completion (39% vs 50%, p?<?0.05) rates; yet had similar rates of Tdap (88% vs 89%, p?>?0.05) and meningococcal (79% vs 83%, p?>?0.05) vaccinations. After adjusting for potential confounders, the regression-adjusted mean rate for HPV vaccine initiation and completion remained significantly lower for “Red” states compared to “Blue” states (57% vs 65%, p?<?0.05, and 41% vs 48%, p?<?0.05, respectively).

Conclusion

HPV vaccination rates are associated with statewide-level voting patterns. Future interventions aimed at improving HPV vaccination rates should consider engaging local and national elected leaders to be proactive in disseminating accurate and authoritative immunization information.  相似文献   
58.
    
  目的:探讨朱砂安神丸对条件性恐惧大鼠恐惧记忆的影响及作用机制。  方法:将90只雄性SD大鼠随机分为空白组、模型组、给药组,每组30只;给药组大鼠灌胃给予朱砂安神丸混悬液(给药体积为每100 g大鼠体质量0.9 mL),空白组、模型组大鼠给予等量的双蒸水,各组大鼠均连续干预7 d。末次给药后复制条件性恐惧模型。通过条件性恐惧实验监测系统观察各组大鼠的僵直反应时间,考察朱砂安神丸对恐惧记忆的影响;通过电生理实验和透射电镜技术,考察朱砂安神丸对海马功能结构可塑性的影响。  结果:与模型组比较,给药组(朱砂安神丸)能有效促进条件性恐惧大鼠恐惧记忆消退,恐惧记忆习得阶段及消退阶段僵直反应时间明显减少,运动时间、运动距离明显增加,诱发海马部位LTP其PS幅值明显减少(P<0.05,P<0.01);海马神经元突触数目较多,突触各部分结构完好、界限清晰,海马突触活性区长度及PSD厚度明显增大,突触间隙宽度明显减小(P<0.05,P<0.01);海马神经元细胞各结构完整清晰,细胞核大,细胞浆内细胞器较多、形态较好。  结论:朱砂安神丸具有促进恐惧记忆消退的作用,其作用机制与保护海马神经元、调节海马突触结构和功能可塑性有关。  相似文献   
59.
杜庆玲  潘恩僦  余飞  李伯休  林新平 《口腔医学》2021,41(12):1134-1137
无托槽隐形矫治凭借美观、舒适等优点,受到众多医生和患者的青睐。因矫治力加载的特殊性,其临床适应症较窄,如何实现牙齿整体移动成为拓宽适应症的重要一环。但目前关于整体移动的研究缺乏系统整理,本文将对整体移动生物力学基础、控根附件种类、控根附件优化措施的相关研究进行归纳,以期为临床上无托槽隐形矫治提供参考。  相似文献   
60.
Osteohistology, the study of bone microstructure, provides an important avenue for assessing extinct and extant vertebrate growth and life history. Cortical vascularity and collagen fibre organization are direct reflections of growth rate, while bone growth marks are indicative of absolute age. However, each skeletal element has its own ontogenetic trajectory and microstructure of certain bones may not be a true representation of whole body growth. Extensive comparative study of modern taxa is required to resolve intraskeletal discrepancies among age, vascularity and tissue organization in extinct vertebrates. Despite their comparative utility, studies of bone microstructure in modern taxa are severely lacking. Here, we add to a growing comparative osteohistological database by describing (1) bone tissue organization, (2) growth mark count, (3) sexually dimorphic bone (e.g. medullary bone) and (4) secondary cortical reconstruction in the bone microstructure of a 14-year-old male and 5-year-old female North Island Brown Kiwi (Apteryx mantelli). Transverse and longitudinal histological ground sections were processed and described for femora, tibiotarsi, tarsometatarsi, humeri, ulnae and radii in both kiwis. Cortical bone can generally be described as parallel-fibered tissue, interrupted by cyclical growth marks, with vascular canals oriented longitudinally within primary and secondary osteons. Tissue morphologically resembling medullary bone is present in the hindlimbs of the female, and coarse compacted cancellous bone (CCCB) is found sporadically in the male and female hindlimbs. Lines of arrested growth (LAGs) are present in all hindlimb bones of both kiwi, but remodelling has obliterated all LAGs in the male ulnae and radii. LAG count varies intraskeletally, but large weight bearing elements such as femora and tibiotarsi have less remodelling and, thus, higher number of LAGs. LAG count did not match absolute age in any skeletal element; a maximum of seven LAGs are present in the male kiwi and a maximum of seven LAGs in the female kiwi. The tissue organization within the forelimbs and hindlimbs is reflective of the protracted growth strategy of the North Island Brown Kiwi and congruent with previous studies of the kiwi. LAGs were highly variable throughout the skeleton of the kiwi and a decoupling of age and LAG deposition is apparent from the male kiwi samples. Excess LAGs in the 5-year-old female kiwi may be a product of hatching, egg laying or captivity. Regardless, LAG count variation in the kiwi stresses the importance of intraskeletal sampling when assessing growth patterns of extinct taxa. An extensive ontogenetic sampling of kiwi is necessary for future investigations of bone growth patterns, CCCB formation, medullary bone and LAG deposition and obliteration in these elusive birds.  相似文献   
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