2,345 research outputs found

    Impact of acute inflammation on spinal motoneuron synaptic plasticity following ventral root avulsion

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    <p>Abstract</p> <p>Background</p> <p>Ventral root avulsion is a proximal nerve root lesion in which ventral motor nerve rootlets are torn from surface of the spinal cord, resulting in extensive death of motoneurons. It has been previously shown that if such lesioning is performed in an animal with experimental autoimmune encephalomyelitis (EAE), a significant number of motoneurons can be rescued despite an intense inflammatory reaction. This rescue effect has been attributed to production of a number of neurotrophic factors by invading T cells. Synaptological changes may be involved in neuronal degeneration, and a better understanding of the role of these changes may be of importance for developing new strategies to promote neuronal survival. The objective of the present work was to evaluate neuronal survival, astroglial reaction and synaptic input changes in spinal cord anterior horn motor nuclei after ventral root avulsion in animals with EAE, both during peak disease and after remission.</p> <p>Methods</p> <p>Lewis rats were subjected to unilateral avulsion of lumbar ventral roots (VRA) and divided into three groups: VRA control, VRA at peak of EAE, and VRA during EAE remission. The animals were sacrificed and their lumbar spinal cords processed for immunohistochemistry, transmission electron microscopy, and motoneuron counting.</p> <p>Results</p> <p>The results indicate a reduction in astroglial reaction, a maintenance of microglial reactivity, and increases in synaptic covering of, and survival of, motoneurons in the VRA+EAE group as compared to VRA alone.</p> <p>Conclusion</p> <p>The present findings indicate that CNS inflammation may directly influence synaptic plasticity as well as the stability of neuronal networks, positively influencing the survival of lesioned neurons.</p

    Morphometry and distribution of sensilla on the antennae of Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae)

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    Antennal sensilla of Anastrepha fraterculus (Wied.) were examined using scanning electron microscopy. In the lagellum, there are trichoid, basiconic, clavate type I and II, and styloconic sensilla and microtrichia. Only microtrichiae and chaetica sensilla were observed in the scape and pedicel. The number of sensilla in the lagellum was similar between sexes. At the apex there was a higher density of trichoid and an absence of clavate sensilla, while basiconic sensilla were more abundant in the proximal region

    Absence of IFNγ expression induces neuronal degeneration in the spinal cord of adult mice

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    <p>Abstract</p> <p>Background</p> <p>Interferon gamma (IFNγ) is a pro-inflammatory cytokine, which may be up-regulated after trauma to the peripheral or central nervous system. Such changes include reactive gliosis and synaptic plasticity that are considered important responses to the proper regenerative response after injury. Also, IFNγ is involved in the upregulation of the major histocompatibility complex class I (MHC class I), which has recently been shown to play an important role in the synaptic plasticity process following axotomy. There is also evidence that IFNγ may interfere in the differentiation and survival of neuronal cells. However, little is known about the effects of IFNγ absence on spinal cord neurons after injury.</p> <p>Methods</p> <p>We performed a unilateral sciatic nerve transection injury in C57BL/6J (wild type) and IFNγ-KO (mutant) mice and studied motoneuron morphology using light and electron microscopy. One week after the lesion, mice from both strains were sacrificed and had their lumbar spinal cords processed for histochemistry (n = 5 each group) and transmission electron microscopy (TEM, n = 5 each group). Spinal cord sections from non-lesioned animals were also used to investigate neuronal survival and the presence of apoptosis with TUNEL and immunohistochemistry.</p> <p>Results</p> <p>We find that presumed motoneurons in the lower lumbar ventral horn exhibited a smaller soma size in the IFNγ-KO series, regardless of nerve lesion. In plastic embedded sections stained with toluidine blue, the IFNγ-KO mice demonstrated a greater proportion of degenerating neurons in the ventral horn when compared to the control series (p < 0.05). Apoptotic death is suggested based on TUNEL and caspase 3 immunostaining. A sciatic nerve axotomy did not further aggravate the neuronal loss. The cellular changes were supported by electron microscopy, which demonstrated ventral horn neurons exhibiting intracellular vacuoles as well as degenerating nuclei and cytoplasm in the IFNγ-KO mice. Adjacent glial cells showed features suggestive of phagocytosis. Additional ultrastructural studies showed a decreased number of pre-synaptic terminals apposing to motoneurons in mutant mice. Nevertheless, no statistical difference regarding the input covering could be detected among the studied strains.</p> <p>Conclusion</p> <p>Altogether, these results suggest that IFNγ may be neuroprotective and its absence results in neuronal death, which is not further increased by peripheral axotomy.</p

    AMBIENTE OBESOGÉNICO EM CRIANÇAS DOS 7 AOS 9

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    Objectivo: Identificar elementos físicos e socioculturais nos micro-ambientes casa e comunidade, associados à obesidade infantil. Metodologia: O estudo foi realizado em 179 crianças, entre os 7 e os 9 anos de idade, das escolas do concelho da Calheta, Região Autónoma da Madeira (RAM). Os parâmetros antropométricos avaliados foram: peso, altura, perímetro do braço e prega cutânea triccipital. Aos pais foi entregue um questionário sobre: aspectos sócio-demográficos; ambiente às refeições; actividades e preferências na ocupação dos tempos livres; aquisição de refeições prontas; tempo de actividade/ inactividade física; infraestruturas habitacionais e recreativas; e estilo parental. Resultados: A prevalência obtida de pré-obesidade foi de 18,4% e a de obesidade infantil foi de 11,2%. Dos factores físicos e sócio culturais estudados os que foram observados na maioria das crianças foram: actividades edentárias (59% referiu ver televisão/ computador entre 1 a 2 horas durante a semana e mais de 2 horas ao fim-de-semana; mais de 70% referiu deslocar-se entre casa e a escola de carro/ autocarro); infra-estruturas habitacionais (82,3% referiu falta de passeios em pelo menos um dos lados da estrada); controlo parental (61% dos pais referiu assumir uma atitude controladora relativamente à alimentação dos filhos). Conclusões: As estratégias de prevenção da obesidade infantil no concelho da Calheta devem ter em conta os factores de risco ambientais identificados neste estudo. As acções devem ser dirigidas à família e envolver os diversos parceiros sociais, de modo a aumentar a actividade física, a reduzir as actividades sedentárias e a reforçar as competências parentais.info:eu-repo/semantics/publishedVersio

    Spinal motoneuron synaptic plasticity after axotomy in the absence of inducible nitric oxide synthase

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    <p>Abstract</p> <p>Background</p> <p>Astrocytes play a major role in preserving and restoring structural and physiological integrity following injury to the nervous system. After peripheral axotomy, reactive gliosis propagates within adjacent spinal segments, influenced by the local synthesis of nitric oxide (NO). The present work investigated the importance of inducible nitric oxide synthase (iNOS) activity in acute and late glial responses after injury and in major histocompatibility complex class I (MHC I) expression and synaptic plasticity of inputs to lesioned alpha motoneurons.</p> <p>Methods</p> <p><it>In vivo </it>analyses were carried out using C57BL/6J-iNOS knockout (iNOS<sup>-/-</sup>) and C57BL/6J mice. Glial response after axotomy, glial MHC I expression, and the effects of axotomy on synaptic contacts were measured using immunohistochemistry and transmission electron microscopy. For this purpose, 2-month-old animals were sacrificed and fixed one or two weeks after unilateral sciatic nerve transection, and spinal cord sections were incubated with antibodies against classical MHC I, GFAP (glial fibrillary acidic protein - an astroglial marker), Iba-1 (an ionized calcium binding adaptor protein and a microglial marker) or synaptophysin (a presynaptic terminal marker). Western blotting analysis of MHC I and nNOS expression one week after lesion were also performed. The data were analyzed using a two-tailed Student's <it>t </it>test for parametric data or a two-tailed Mann-Whitney <it>U </it>test for nonparametric data.</p> <p>Results</p> <p>A statistical difference was shown with respect to astrogliosis between strains at the different time points studied. Also, MHC I expression by iNOS<sup>-/- </sup>microglial cells did not increase at one or two weeks after unilateral axotomy. There was a difference in synaptophysin expression reflecting synaptic elimination, in which iNOS<sup>-/- </sup>mice displayed a decreased number of the inputs to alpha motoneurons, in comparison to that of C57BL/6J.</p> <p>Conclusion</p> <p>The findings herein indicate that iNOS isoform activity influences MHC I expression by microglial cells one and two weeks after axotomy. This finding was associated with differences in astrogliosis, number of presynaptic terminals and synaptic covering of alpha motoneurons after lesioning in the mutant mice.</p

    Rates of Low-Value Service in Australian Public Hospitals and the Association With Patient Insurance Status.

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    Importance: Low-value services have limited or no benefit to patients. Rates of low-value service in public hospitals may vary by patient insurance status, given that there may be different financial incentives for treatment of privately insured patients. Objective: To assess the variation in rates of 5 low-value services performed in Australian public hospitals according to patient funding status (ie, private or public). Design, Setting, and Participants: This retrospective cross-sectional study analyzed New South Wales public hospital data from January 2013 to June 2018. Patients included in the sample were over age 18 years and eligible to receive low-value services based on diagnoses and concomitant procedures. Data analysis was conducted from June to December 2020. Main Outcomes and Measures: Hospital-specific rates of low-value knee arthroscopic debridement, vertebroplasty for osteoporotic spinal fractures, hyperbaric oxygen therapy, oophorectomy with hysterectomy, and laparoscopic uterine nerve ablation for chronic pelvic pain were measured. For each measure, rates within each public hospital were compared by patient funding status descriptively and using multilevel models. Results: A total of 219 862 inpatients were included in analysis from 58 public hospitals across the 5 measures. A total of 38 365 (22 904 [59.7%] women; 12 448 [32.4%] aged 71-80 years) were eligible for knee arthroscopic debridement for osteoarthritis; 2520 (1924 [76.3%] women; 662 [26.3%] aged 71-80 years), vertebroplasty for osteoporotic spinal fractures; 162 285 (82 046 [50.6%] women; 28 255 [17.4%] aged 61-70 years), hyperbaric oxygen therapy; 15 916 (7126 [44.8%] aged 41-50 years), oophorectomy with hysterectomy; and 776 (327 [42.1%] aged 18-30 years), uterine nerve ablation for chronic pelvic pain. Overall rates of low-value services varied considerably between measures, with the lowest rate for hyperbaric oxygen therapy (0.3 procedures per 1000 inpatients [47 of 158 220 eligible inpatients]) and the highest for vertebroplasty (30.8 procedures per 1000 eligible patients [77 of 2501 eligible inpatients]). There was significant variation in rates between hospitals, with a few outlying hospitals (ie, <10), particularly for knee arthroscopy (range from 1.8 to 21.0 per 1000 eligible patients) and vertebroplasty (range from 13.1 to 70.4 per 1000 eligible patients), with higher numerical rates of low-value services among patients with private insurance than for those without. However, there was no association overall between patient insurance status and low-value services. Overall differences in rates among those with and without private insurance by individual procedure type were not statistically significant. Conclusions and Relevance: There was significant variation in rates of low-value services in public hospitals. While there was no overall association between private insurance and rate of low-value services, private insurance may be associated with low-value service rates in some hospitals. Further exploration of factors specific to local hospitals and practices are needed to reduce this unnecessary care

    Critical evaluation of proteomic protocols for passion fruit (Passiflora edulis Sims) leaves, a crop with juice market benefits

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    Passion fruit grows practically all over Brazilian territory; its production is largely destined to juice industry and expanding to overseas markets. The suitability of four protein extraction protocols for plant proteome was  investigated to determine the best choice for studies concerning passion fruit leaf proteins. Trichloroacetic acid (TCA)/acetone extraction; isoelectric  focusing (IEF) buffer extraction; phenol (Phe) extraction and Phe-SDS extraction were tested. The Phe method produced the best results, showing higher reproducibility of resolved protein spots and clearer 2D gel  background staining. In comparison, the Phe-SDS method presented fewer spots and lower reproducibility. The TCA/acetone method produced the fewest identifiable spots and the IEF buffer produced the poorest results,displaying fewer reproducibly detected spots, more vertical streaks and darker 2D staining. Selected spots, obtained with Phe method, were identified by spectrometric analysis (MALDI-TOF-TOF) to exemplify the viability to perform more comprehensive proteomic studies with passion fruit leaves and, therefore increase information about stress-related and developmental responses in this fruit crop.Key words: Passion fruit, proteomic, protein extraction, juice industry

    In-hospital outcomes by insurance type among patients undergoing percutaneous coronary interventions for acute myocardial infarction in New South Wales public hospitals

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    Background: International evidence suggests patients receiving cardiac interventions experience differential outcomes by their insurance status. We investigated outcomes of in-hospital care according to insurance status among patients admitted in public hospitals with acute myocardial infarction (AMI) undergoing percutaneous coronary intervention (PCI). Methods: We conducted a cohort study within the Australian universal health care system with supplemental private insurance. Using linked hospital and mortality data, we included patients aged 18 + years admitted to New South Wales public hospitals with AMI and undergoing their first PCI from 2017–2020. We measured hospital-acquired complications (HACs), length of stay (LOS) and in-hospital mortality among propensity score-matched private and publicly funded patients. Matching was based on socio-demographic, clinical, admission and hospital-related factors. Results: Of 18,237 inpatients, 30.0% were privately funded. In the propensity-matched cohort (n = 10,630), private patients had lower rates of in-hospital mortality than public patients (odds ratio: 0.59, 95% CI: 0.45–0.77; approximately 11 deaths avoided per 1,000 people undergoing PCI procedures). Mortality differences were mostly driven by STEMI patients and those from major cities. There were no significant differences in rates of HACs or average LOS in private, compared to public, patients. Conclusion: Our findings suggest patients undergoing PCI in Australian public hospitals with private health insurance experience lower in-hospital mortality compared with their publicly insured counterparts, but in-hospital complications are not related to patient health insurance status. Our findings are likely due to unmeasured confounding of broader patient selection, socioeconomic differences and pathways of care (e.g. access to emergency and ambulatory care; delays in treatment) that should be investigated to improve equity in health outcomes
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