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Absence of presynaptic protein MUNC18-1 (gene: Stxbp1) leads to neuronal cell death at an immature stage before synapse formation. Here, we performed transcriptomic and proteomic profiling of immature Stxbp1 knockout (KO) cells to discover which cellular processes depend on MUNC18-1. Hippocampi of Stxbp1 KO mice showed cell-type specific dysregulation of 2123 transcripts primarily related to synaptic transmission and immune response. To further investigate direct, neuron-specific effects of MUNC18-1 depletion, a proteomic screen was performed on murine neuronal cultures at two developmental timepoints prior to onset of neuron degeneration. 399 proteins were differentially expressed, which were primarily involved in synaptic function (especially synaptic vesicle exocytosis) and neuron development. We further show that many of the downregulated proteins upon loss of MUNC18-1 are normally upregulated during this developmental stage. Thus, absence of MUNC18-1 extensively dysregulates the transcriptome and proteome, primarily affecting synaptic and developmental profiles. Lack of synaptic activity is unlikely to underlie these effects, as the changes were observed in immature neurons without functional synapses, and minimal overlap was found to activity-dependent proteins. We hypothesize that presence of MUNC18-1 is essential to advance neuron development, serving as a 'checkpoint' for neurons to initiate cell death in its absence.Significance StatementPresynaptic protein MUNC18-1 is essential for neuronal functioning. Pathogenic variants in its gene, STXBP1, are among the most common found in patients with developmental delay and epilepsy. To discern the pathogenesis in these patients, a thorough understanding of MUNC18-1's function in neurons is required. Here, we show that loss of MUNC18-1 results in extensive dysregulation of synaptic and developmental proteins in immature neurons before synapse formation. Many of the downregulated proteins are normally upregulated during this developmental stage. This indicates that MUNC18-1 is a critical regulator of neuronal development, which could play an important role in the pathogenesis of STXBP1 variant carriers.
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Synaptic transmission is the predominant form of communication in the brain. It requires functionally specialized molecular machineries constituted by thousands of interacting synaptic proteins. Here, we made use of recent advances in cross-linking mass spectrometry (XL-MS) in combination with biochemical and computational approaches to reveal the architecture and assembly of synaptic protein complexes from mouse brain hippocampus and cerebellum. We obtained 11,999 unique lysine-lysine cross-links, comprising connections within and between 2362 proteins. This extensive collection was the basis to identify novel protein partners, to model protein conformational dynamics, and to delineate within and between protein interactions of main synaptic constituents, such as Camk2, the AMPA-type glutamate receptor, and associated proteins. Using XL-MS, we generated a protein interaction resource that we made easily accessible via a web-based platform (http://xlink.cncr.nl) to provide new entries into exploration of all protein interactions identified.
Assuntos
Proteômica , Sinapses/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/química , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Modelos Moleculares , Ligação Proteica , Conformação Proteica , Domínios e Motivos de Interação entre Proteínas , Mapeamento de Interação de Proteínas , Mapas de Interação de Proteínas , Proteínas/química , Proteínas/metabolismo , Proteômica/métodos , Reprodutibilidade dos Testes , Relação Estrutura-Atividade , Espectrometria de Massas em Tandem , Fluxo de TrabalhoRESUMO
The objective of this study was to evaluate the effect of birth order on the physiological and metabolic responses of the newborn piglet the first hours after birth. A total of 281 randomly selected newborn piglets were included, classified according to birth order in 12 groups (L1-L12). The expulsion interval, neonatal vitality, latency in connecting to the maternal teat and physiological profile were recorded for each piglet. The number of piglets born alive and dead was also recorded. The blood gases, electrolytes and glucose levels of the neonates were obtained by means of an automatic blood gas and electrolyte analyzer. Groups L1, L2, L11, and L12 had the least score on the vitality scale, the longest expulsion intervals, and longest latency to connect with the maternal teat, as well as greater physiological alterations (hyperglycemia, hyperlactatemia and hypercapnia) compared to groups L4 to L9. Likewise, type-II stillbirths only occurred in the first and last quarter of the birth order of the litter. In conclusion, piglets born in the first and last quarter of the birth order of the litter had a greater risk of having physiological and behavioral alterations during farrowing.
Assuntos
Animais Recém-Nascidos/fisiologia , Ordem de Nascimento , Suínos/fisiologia , Animais , Animais Recém-Nascidos/metabolismo , Peso ao Nascer , Feminino , Parto , Gravidez , Natimorto , Suínos/metabolismoRESUMO
Hybrid bionanocomposites based on cellulose matrix, with silica nanoparticles as reinforcers, were prepared by one-pot synthesis of cellulose surface modified by solvent exchange method to keep the biopolymer net void for hosting inorganic nanoparticles. Neither expensive inorganic-particle precursors nor crosslinker agents or catalysts were used for effective dispersion of reinforcer concentration up to 50 wt %. Scanning electron microscopy of the nanocomposites shows homogeneous dispersion of reinforcers in the surface modified cellulose matrix. The FTIR spectra demonstrated the cellulose features even at 50 weight percent content of silica nanoparticles. Such a high content of silica provides high thermal stability to composites, as seen by TGA-DSC. The fungi decay resistance to Trametes versicolor was measured by standard test showing good resistance even with no addition of antifungal agents. This one-pot synthesis of biobased hybrid materials represents an excellent way for industrial production of high performance materials, with a high content of inorganic nanoparticles, for a wide variety of applications.
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The objective was to measure the effects of VC (a uterotonic drug with vasodilator effects) in eutocic and dystocic sows, on the acid-base balance and some vitality traits of piglets at birth. Farrowing was induced with prostaglandin F2α. Four groups of sows (20 sows/group) were monitored; Groups 1 and 2 were eutocic sows, whereas Groups 3 and 4 were dam-fetal dystocic sows. Groups 1 and 3 (control) were given saline, whereas Groups 2 and 4 were given VC im (1.66 mg/kg of body weight) after the first piglet was born. Piglets' physio-metabolic performance was monitored peripartum. Treatment with VC reduced (P<0.0001) the percentage of intrapartum stillbirths in sows either with eutocic (5.2 vs. 10.0%) and dystocic (7.6 vs. 16.7%) farrowings and increased (P<0.0001) the number of pigs born alive without any evidence of AFS (89.9 vs. 79.9%, eutocic and 81.6 vs. 65.2%, dystocic). In addition, for the group of pigs with no acute fetal suffering (AFS), VC treatment enhanced survival responses with a half point grater vitality score in Group 4; it also reduced the latency to first teat contact by 6 min (P<0.05) in both treated groups compared to controls; and it improved the condition of the pigs' umbilical cord, with more adhered (98 vs. 86% in eutocic and 88 vs. 80% in dystocic; P<0.05) and less ruptured cords. Moreover, VC reduced the severity of adverse physio-metabolic indicators and the acid-base balance of piglets with AFS at birth by lowering blood lactate (89.8 vs. 93.5 mmol/L in eutocic groups and 94.6 vs. 100.2 mmol/L in dystocic groups; P<0.05), PaCO2 and Ca2+, and by increasing blood pH, HCO3 and PaO2 levels (P<0.05).
Assuntos
Equilíbrio Ácido-Base/efeitos dos fármacos , Benzilaminas/uso terapêutico , Distocia/veterinária , Ocitócicos/uso terapêutico , Animais , Animais Recém-Nascidos , Distocia/tratamento farmacológico , Feminino , Gravidez , Natimorto/veterinária , Suínos , Cordão UmbilicalRESUMO
The aims of the study were to characterize the uterine activity in sows treated with vetrabutin chlorhydrate (VC), an uterotonic and muscle-tropic drug during farrowing, and to measure the effects of the drug on piglet neonatal viability. The experiment involved 1478 piglets from 130 Yorkshire-Landrace sows, randomly allotted into two groups. Farrowing monitoring began 12 h after PGF2alpha synchronization. Group 1 was given physiological solution (G1, n = 65); Group 2 was treated with VC (1 mL/60 kg LW) at the initiation of fetal expulsion (G2, n = 65). In spite of the total duration of expulsion being significantly longer (P < 0.0001), approximately 35 min in the VC treatment, VC application at the time the first piglet was expulsed favored the alive birth of at least one more piglet. Even though the pressure in the uterus was similar in both groups, the number and duration of uterus contractions recorded were significantly less (P < 0.0001) in G2, favoring fewer births with acute fetal suffering, compared with that in G1. VC treated group compared with the control group also had fewer (5.01% vs. 24%) alterations in umbilical cords, as well as a lesser incidence of secondary apnea (2.08% vs. 7.46%) and bradycardia (1.94% vs. 7.61%), which favored a significantly higher vitality score (P < 0.002). With the intent to evaluate uterine activity in sows during the farrowing process, we propose using the equation used in human medical practices to calculate Montevideo Units applied to swine obstetrics for the first time.
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Benzilaminas/farmacologia , Monitorização Fetal/veterinária , Trabalho de Parto/efeitos dos fármacos , Trabalho de Parto/fisiologia , Suínos/fisiologia , Contração Uterina/efeitos dos fármacos , Animais , Dinoprosta/análogos & derivados , Dinoprosta/farmacologia , Feminino , Ocitócicos/farmacologia , GravidezRESUMO
OBJECTIVES: To find the variability in women's appearance at three moments of their life cycle and its relationship with practices aiming at weight loss, analysing the efficacy of this behaviour. DESIGN: Cross-sectional. SETTING: Women from the Community of Madrid who formed part of an investigation by the Unit of Anthropology of the Department of Biology of the Autonomous University of Madrid (UAM) into perception of image and associated behaviour as a function of age, body mass index, and social and economic conditions. PARTICIPANTS: 535 women in three age groups: 200 adolescents belonging to two secondary schools in Madrid; 202 university students from the Biology Faculty of the UAM, and 135 women aged between 45 and 65 and living in the Madrid area of Alcobendas, who were taking part in a women's health programme run by the Alcobendas town council. MATERIAL AND METHODS: Information was collected on body measurements, self-perception and image assessment, with perception indicators and body form indicators contrasted. RESULTS: There were a great many attempts to lose weight by adolescents and women over 45, with the starting age for such practices much earlier in the adolescents' and students' groups. It was particularly striking that 44% of the adolescents within the thin category had tried to lose weight. Among the students and women over 45 this percentage rose in consonance with their overweight. The older women were more effective at losing weight, but it was very difficult for them to maintain this loss. The speed of weight loss was higher in women with higher body mass index. CONCLUSIONS: Physical appearance varies between young women and women over 45, in that the former are taller, thinner and with a straighter figure. Despite this, young women develop behaviour designed to lose weight much more often than older women, with an earlier starting age and more rapidly, which can have serious health consequences.