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41.
Jonathan M. Blagburn Maria A. Sosa Rosa E. Blanco 《The Journal of comparative neurology》1996,373(4):511-528
The mechanisms by which neurons recognize the appropriate postsynaptic cells remain largely unknown. A useful approach to this problem is to use a system with a few identifiable neurons that form highly specific synaptic connections. We studied the development of synapses between two identified cercal sensory afferents and two giant interneurons (GIs) in the embryonic cockroach Periplaneta americana. By 46% of embryonic development, the axons of the filiform hair sensory neurons have entered the terminal ganglionic neuropil and grow alongside the GI primary dendrites, although they do not form synapses. From 50% of development, the GI dendrites grow outward from the center of the neuropil to contact the presynaptic axons and their branches. The sensory neurons begin to spike at 52% of development, and, from 55% of development, these action potentials evoked excitatory postsynaptic potentials in the GIs. Synaptic contacts were first seen at this time. The pattern of synaptic connections was highly specific from the outset. GI2 had strong input from the medial (M) afferent and had almost negligible input from the lateral (L) afferent, whereas GI3 had input from both. This specificity was present before bursts of spontaneous activity began in the sensory neurons at 59% of development. GI2 filopodia selectively formed synaptic contacts with the M axon rather than the L axon. The few contacts made by GI2 with the L axon had a normal morphology but fewer presynaptic densities. Filopodial insertions were not involved in selective synapse formation. In this system, highly specific synaptic recognition appears to be activity independent. © 1996 Wiley-Liss, Inc. 相似文献
42.
43.
Otilia Perichart-Perera Jennifer Mier-Cabrera Claudia Montserrat Flores-Robles Nayeli Martínez-Cruz Lidia Arce-Snchez Itzel Nallely Alvarado-Maldonado Araceli Montoya-Estrada Jos Romo-Yaez Ameyalli Mariana Rodríguez-Cano Guadalupe Estrada-Gutierrez Salvador Espino y Sosa Mario Guzmn-Huerta Rodrigo Ayala-Yaez Enrique Reyes-Muoz 《Nutrients》2022,14(1)
The aim of this study was to examine the efficacy of intensive medical nutrition therapy (MNT) plus metformin in preventing gestational diabetes mellitus (GDM) among high-risk Mexican women. An open-label randomized clinical trial was conducted. Inclusion criteria were pregnant women with three or more GDM risk factors: Latino ethnic group, maternal age >35 years, body mass index >25 kg/m2, insulin resistance, and a history of previous GDM, prediabetes, a macrosomic neonate, polycystic ovarian syndrome, or a first-degree relative with type 2 diabetes. Women before 15 weeks of gestation were assigned to group 1 (n = 45): intensive MNT-plus metformin (850 mg twice/day) or group 2 (n = 45): intensive MNT without metformin. Intensive MNT included individual dietary counseling, with ≤50% of total energy from high carbohydrates. The primary outcome was the GDM incidence according to the International Association of Diabetes Pregnancy Study Groups criteria. There were no significant differences in baseline characteristics and adverse perinatal outcomes between the groups. The GDM incidence was n = 11 (24.4%) in the MNT plus metformin group versus n = 7 (15.5%) in the MNT without metformin group: p = 0.42 (RR: 1.57 [95% CI: 0.67–3.68]). There is no benefit in adding metformin to intensive MNT to prevent GDM among high-risk Mexican women. Clinical trials registration: . NCT01675310相似文献
44.
Bassem D. Khalil Roberto Sanchez Tasrina Rahman Carolina Rodriguez-Tirado Stefan Moritsch Alba Rodriguez Martinez Brett Miles Eduardo Farias Mihaly Mezei Ana Rita Nobre Deepak Singh Nupura Kale Karl Christoph Sproll Maria Soledad Sosa Julio A. Aguirre-Ghiso 《The Journal of experimental medicine》2022,219(1)
45.
Laura MaciasMuoz Beatriz FradeSosa Jose IniciarteMundo Susana Hidalgo Rosa Maria Morla Yadira Gallegos Raimon Sanmarti Josep Maria Auge 《Journal of clinical laboratory analysis》2022,36(3)
BackgroundCalprotectin is a calcium‐binding protein that can be measured in serum, plasma, and feces. Increased serum and plasma calprotectin concentrations have been found in chronic inflammatory rheumatic disorders. An analytical and clinical evaluation of the DiaSorin Liaison® fecal Calprotectin assay using LIAISON® XL was performed.MethodsThe protocol included an analytical and clinical evaluation in which imprecision, the linearity of dilution, differences between serum and plasma samples and method comparison with CalproLab™ ELISA kit were assessed. Serum calprotectin concentrations in active (n = 26) and remission (n = 23) rheumatoid arthritis (RA) patients were compared.ResultsThe intra‐day and inter‐day analytical imprecision CVs ranged from 2.9% to 4.0% and 2.7% to 10.4%, respectively. Correlation between measured and expected values was high (R > 0.99), indicating good linearity. The Wilcoxon signed‐rank test showed that serum and plasma matched samples presented statistically significant differences (p < 0.001) being the highest concentrations of calprotectin observed in serum samples. Deming regression equation was as follows: Diasorin calprotectin (μg/ml) = −0.32 (95% CI: −0.65 ‐ −0.05) +1.58 (95% CI: 1.42–1.79).* Calprolab calprotectin (μg/ml). Significantly higher serum calprotectin levels were found in RA patients with active disease when compared to patients with low disease activity or in clinical remission (mean ± SD) [(3.35 μg/ml ± 1.55) vs. (1.63 μg/ml ± 0.52), p < 0.001] and these levels correlated well with all disease activity indices.ConclusionsThe DiaSorin Liaison® fecal Calprotectin assay adapted for serum samples showed adequate technical performances and the clinical performances were similar to other assays. 相似文献
46.
Isha Lopez M.D. Lucio Zapata B.S. Jr. Juan Jesús Sosa B.S. Clifford Rodgers B.S. Maria Ruiz B.S. Susan Oh M.D. Linda S. Hynan Ph.D. Alexa B. Kimball M.D. M.P.H. Amit G. Pandya M.D. 《Pediatric dermatology》2016,33(5):e292-e293
We performed a cross‐sectional study of Hispanic and non‐Hispanic parents of children with acne using a survey designed to determine their level of awareness of acne and its treatment; 82% of Hispanic parents and 40% of non‐Hispanic parents agreed that a health care provider should treat mild acne (p < 0.001). Hispanic parents of adolescents with acne agreed more frequently than non‐Hispanic parents that children with mild and moderate acne should be taken to a health care provider for treatment, but they tended not to visit health care providers. Future studies should aim to determine the reasons for this discrepancy, after which culturally sensitive educational programs can be developed to address this disparity. 相似文献
47.
Prefrontal cortex,hippocampus, and basolateral amygdala plasticity in a rat model of autism spectrum
Nuvia Sosa‐Díaz Maria Elena Bringas Marco Atzori Gonzalo Flores 《Synapse (New York, N.Y.)》2014,68(10):468-473
We aimed to investigate the effect of prenatal administration of valproic acid (VPA) (500 mg/kg) at embryonic day 12.5 on the anatomical properties of the prefrontal cortex, hippocampus, and basolateral amygdala, at three different ages: immediately after weaning (postnatal day 21 [PD21]), prepubertal (PD35), and postpubertal (PD70) ages in a rat model of autistic spectrum disorder. Quantitative analysis of the thickness of the prefrontal cortex revealed a reduced size at all study ages in the cingulate 1 area of the prefrontal cortex and CA1 of the dorsal hippocampus in prenatally exposed animals compared to controls. At the level of the basolateral amygdala, a reduction in the size was observed at PD35 and PD70 in the VPA group. In addition, a reduced thickness was observed in the prelimbic region of the prefrontal cortex in VPA animals at PD35. Interestingly, no differences in cortical thickness were observed between control and VPA animals in the infralimbic region of the prefrontal at any age. Our results suggest that prenatal exposure to VPA differentially alters cortical limbic regions anatomical parameters, with implication in the autistic spectrum disorder. Synapse 68:468–473, 2014 . © 2014 Wiley Periodicals, Inc. 相似文献
48.
Cuccia Vicente Zuccaro Graciela Sosa Fidel Monges Jorge Lubienieky Fabiana Taratuto Ana Lia 《Child's nervous system》2003,19(4):232-243
METHODS: Out of 105 patients with tuberous sclerosis (TS) admitted to the Hospital Nacional de Pediatría "Juan P. Garrahan" (Buenos Aires, Argentina), we surgically treated 17 children between January 1988 and December 2000. Two patients were operated on because of epilepsy and 15 patients because of an intraventricular tumor (subependymal giant cell astrocytoma [SGCA]). In this report we focus on tumors. Twelve of the 15 patients presented with hydrocephalus but none of them had a preoperative shunt. All tumors were surgically resected using frontal transventricular or transcallosal routes. Total removal was achieved in 12 out of 15 and subtotal removal in 3 out of 15 patients (resection of 70-95%). RESULTS: Exeresis of the tumor was not accompanied by significant morbidity and there was no perioperative mortality. Seizures and mental retardation did not improve after tumor resection. It was necessary to insert a postoperative shunt a long time after surgery in only one patient. There were no recurrences of SGCA that were totally removed after a mean follow-up of 51.7 months. CONCLUSIONS: We encourage surgery as soon as a lesion is diagnosed as a tumor. The "transformation" of subependymal nodules (SEN) into tumors (SGCA) may be considered controversial. 相似文献
49.
Brain metastases are the most commonly seen intracranial lesions in adults. What is more, meningiomas are the most common primary intracranial tumours after gliomas and their imaging characteristics are well known in both CT and MRI scans. However, there are lesions that can mimic meningiomas in imaging studies, including metastases of extracranial tumours, confronting us with a diagnostic and therapeutic challenge. We present the case of a patient with meningeal metastasis of a uterine leiomyosarcoma that was not known at the time of the surgical intervention. 相似文献
50.
J. Ventura‐Juarez MR. Campos‐Esparza J. Pacheco‐Yepez J. A López‐Blanco A. Adabache‐Ortíz M. Silva‐Briano R. Campos‐Rodríguez 《Parasite immunology》2016,38(8):503-509
Entamoeba histolytica invades the intestine and other organs during the pathogenesis of amoebiasis. In the early stages, the host organism responds with an inflammatory infiltrate composed mostly of neutrophils. It has been reported that these immune cells, activated by E. histolytica, exert a protective role by releasing proteolytic enzymes and generating reactive oxygen/nitrogen species (ROS/RNS) and antimicrobial peptides. It is now known that neutrophils also produce neutrophil extracellular traps (NETs), which are able to damage and kill pathogens. Studies have shown that intracellular protozoan pathogens, including Toxoplasma gondi, Plasmodium falciparum and Leishmania spp, induce neutrophils to release NETs and are damaged by them. However, the action of this mechanism has not been explored in relation to E. histolytica trophozoites. Through scanning electron, epifluorescence microscopy and viability assays, we show for first time that during in vitro interaction with E. histolytica trophozoites, human neutrophils released NETs that covered amoebas and reduced amoebic viability. These NETs presented histones, myeloperoxidase and decondensed chromatin. The results suggest that NETs participate in the elimination of the parasite. 相似文献