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141.
The tubulinopathies refer to a wide range of brain malformations caused by mutations in one of the seven genes encoding different tubulin's isotypes. The β‐tubulin isotype III (TUBB3) gene has a primary function in nervous system development and axon generation and maintenance, due to its neuron‐specific expression pattern. A recurrent heterozygous mutation, c.1228G > A; p.E410K, in TUBB3 gene is responsible of a rare disorder clinically characterized by congenital fibrosis of the extraocular muscle type 3 (CFEOM3), intellectual disability and a wide range of neurological and endocrine abnormalities. Other mutations have been described spanning the entire gene and genotype–phenotype correlations have been proposed. We report on a 3‐year‐old boy in whom clinical exome sequencing allowed to identify a de novo TUBB3 E410K mutation as the molecular cause underlying a complex phenotype characterized by a severe bilateral palpebral ptosis refractory to eye surgery, psychomotor delay, absent speech, hypogonadism, celiac disease, and cyclic vomiting. Brain MRI revealed thinning of the corpus callosum with no evidence of malformation cortical dysplasia. We reviewed available records of patients with TUBB3 E410K mutation and compared their phenotype with the clinical outcome of patients with other mutations in TUBB3 gene. The present study confirms that TUBB3 E410K results in a clinically recognizable phenotype, unassociated to the distinct cortical dysplasia caused by other mutations in the same gene. Early molecular characterization of TUBB3 E410K syndrome is critical for targeted genetic counseling and prompt prospective care in term of neurological, ophthalmological, endocrine, and gastrointestinal follow‐up.  相似文献   
142.
Human KB cell lines resistant to high levels of colchicine were isolated by several successive single-step selections. Most of these selection steps resulted in cross-resistance to vincristine, vinblastine, adriamycin, actinomycin D, and puromycin; however, at the highest levels of colchicine resistance, increased cross-resistance to other drugs was not observed. There was no major change in protein synthesis or alteration in protein phosphorylation or [14C]glucosamine labeling patterns accompanying the development of multiple drug resistance as measured by analysis of metabolically labeled proteins on SDS gels. Cell-cell hybridization experiments showed that the colchicine-resistant and multiple drug-resistant phenotypes were incompletely dominant. In addition, colchicine resistance was found to segregate independently from resistance to other drugs in one somatic cell hybrid, suggesting that complex genetic loci are involved in the development of the multiple drug-resistant phenotype. These mutants should be useful for the study of the clinically important problem of multiple drug resistance in human cancer.  相似文献   
143.
In 18-week-old nulliparous rabbit dose, ovulation was inducedwith 50 IU of pure urinary luteinizing hormone (LH; LHgroup),or 50 IU of ohuman chorionic gonadotrophin (HCG; HCG group),in order to detemine the effect of these treatments on 17-oestradioland progesterone concentrations, and on oocyte and embryo quality.Luteinizing follicles, recovered oocytes, progesteronoe concentrationand grade 5 embryos were significantly reduced when pure urinaryLH was used. Statistically significant correlations were found:(i) between oestradiol concentration and number of degeneratedoocytes in both groups (positive); (ii) between oestradiol concentrationand grade 1 and 2 embrayos (negative), and grade 5 embryos (positive)in the HCG group; (iii) between progesteronoe concentrationand metaphase II oocytes(negatice), and between progesteroneand grade 5 sembryos (positive), in the HCG group; and (iv)between progesterone and oestradiol concentrations (negative)in the LH group. It seems that the oestrsdiol to progegsteroneratio improves during the early luteal phase when ovulationis induced with LH, and that oestradiol and progesterone concentrationscould play a role in dtermining oocyte and embryo quality  相似文献   
144.
We report three cases of well-differentiated neuroendocrine carcinoma originating primarily in the anterior mediastinum which had been initially investigated by fine-needle aspiration cytology in conjunction with immunocytochemistry and subsequently recognized as thymic in origin. Aspirates consisted of loosely cohesive or aggregated medium sized elements with round to oval nuclei and scanty cytoplasm. in all cases the Romanowsky stain provided an excellent delineation of definite paranuclear inclusion-like structures having a semicircular or discoid appearance which appeared to contain cytokeratin by immunocytochemical studies and were very similar to the intermediate filament paranuclear “buttons” found in neuroendocrine Merkel cell carcinoma of the skin. This appears to be a novel cytologic observation for thymic neuroendocrine carcinoma. We discuss the significance of the above cytologic and immunocytochemical findings and their possible role in the diagnosis of thymic neuroendocrine carcinoma by fine-needle aspiration biopsy. © 1995 Wiley- Liss, Inc.  相似文献   
145.
Summary Healthy volunteers administered orally a single dose (20 mg) of [2-14C]zetidoline, a new dopamine antagonist, exhibited rapid absorption of radioactivity with peak plasma levels of 250–300 ng/ml achieved in 1 h. The compound underwent intensive metabolic first-pass so that plasma radioactivity was represented mostly by two products, metabolite B endowed with neuroleptic activity, and metabolite D inactive, while unchanged zetidoline was not detected. Disappearance of radioactivity from plasma was rapid with a half-life of 1.78±0.20 h.The simultaneous assay of plasma prolactin showed increased levels of the hormone (+464% at the peak time) up to the 6th h after dosing, with plasma concentration profile which mimic those of metabolite B.The radioactive test-dose was eliminated mainly via the kidneys with an average urinary recovery of 84.7±1.7% in 4 days (73.4±1.1% within 8 h). The main urinary metabolite (metabolite G) and two minor ones (metabolites B and D) were purified and their structures assigned by IR, MS and NMR spectroscopy, they are: 1-(3-chloro-4-hydroxyphenyl)-3[2-(3,3-dimethyl-1-azetidinyl)ethyl]imidazolidin-2-one, metabolite B; 1-[2-(3,3-dimethyl-1-azetidinyl)ethyl]imidazolidin-2-one, metabolite D and the 4-O-sulphate ester of metabolite B, metabolite G.The metabolic fate of zetidoline in man follows the same phase I reactions demonstrated in rats and dogs, while the phase II reaction is sulphoconjugation instead of the glucuronidation observed in animals.  相似文献   
146.
An in vivo model of liver hyperplastic noduligenesis was inducedin rats by long-term administration of thioacetamide (TAM) (50mg/kg/day i.p.). Three doses of 50 mg/kg of an antitumoral Rh(III)complex were administered at 14, 9 and 5 days before the endof TAM treatment. Plasma and urine were obtained from eitherTAM or Rh(III) complex or TAM plus Rh(III) complex treated ratsto determine the interactions of both substances with the biochemicalparameters related to liver function. The rise in alkaline phosphatase(ALP), teucine aminopeptidase (LAP), -gtutamyl transferase (GGT)and the unchanged activities in the aspartate and alanine aminotransferases(AST, ALT) in plasma of TAM-treated rats indicated that thedisease induced by this substance can be considered as a chronicobstructive biliary disease with indices of cell proliferationand tumors. The increased concentration of bilirubin both inthe plasma and urine of TAM-treated rats suggested liver cholestasisand hepatobiliary obstruction. The very low values of creatinineclearance indicated that there was some degree of kidney failuredue to the effect of TAM. The increased concentration of ammoniaboth in plasma and urine were probably a consequence of thedecreased flux in the urea cycle in the liver. The Rh(III) complexalone did not produce significant changes in the plasma enzymeactivities. The only significant changes were found in the concentrationsof uric acid and ammonia in the urine. When the Rh(III) complexwas administered to TAM-treated rats, significant restorationof the following parameters were observed: plasma enzymaticactivities, blood bilirubin and ammonia, uric acid and creatininein the urine and the creatinine clearance. These results suggestthat the altered liver function induced by TAM can be restoredby Rh(III) complex. The mechanisms by which this complex actsto counteract the TAM-induced changes are not yet established.  相似文献   
147.
Journal of Public Health - This study aimed at assessing emergency medical service (EMS) use by patients with acute myocardial infarction (AMI), factors associated with EMS use, and outcomes in the...  相似文献   
148.
Advances in Health Sciences Education - Background: Despite being a mandated, foundational value in healthcare, research on compassion remains limited. Studying the individual, patient, clinical,...  相似文献   
149.
Aging is associated with a progressive decline in skeletal muscle mass, strength and function (sarcopenia). We have investigated whether a mixture of algae oil (25%) and extra virgin olive oil (75%) could exert beneficial effects on sarcopenia. Young (3 months) and old (24 months) male Wistar rats were treated with vehicle or with the oil mixture (OM) (2.5 mL/kg) for 21 days. Aging decreased gastrocnemius weight, total protein, and myosin heavy chain mRNA. Treatment with the OM prevented these effects. Concomitantly, OM administration decreased the inflammatory state in muscle; it prevented the increase of pro-inflammatory interleukin-6 (IL-6) and the decrease in anti-inflammatory interleukin-10 (IL-10) in aged rats. The OM was not able to prevent aging-induced alterations in either the insulin-like growth factor I/protein kinase B (IGF-I/Akt) pathway or in the increased expression of atrogenes in the gastrocnemius. However, the OM prevented decreased autophagy activity (ratio protein 1A/1B-light chain 3 (LC3b) II/I) induced by aging and increased expression of factors related with muscle senescence such as histone deacetylase 4 (HDAC-4), myogenin, and IGF-I binding protein 5 (IGFBP-5). These data suggest that the beneficial effects of the OM on muscle can be secondary to its anti-inflammatory effect and to the normalization of HDAC-4 and myogenin levels, making this treatment an alternative therapeutic tool for sarcopenia.  相似文献   
150.
Varicocele is an age-related disease with no current medical treatments positively impacting infertility. Toll-like receptor 4 (TLR4) expression is present in normal testis with an involvement in the immunological reactions. The role of peroxisome proliferator-activated receptor-α (PPAR-α), a nuclear receptor, in fertility is still unclear. N-Palmitoylethanolamide (PEA), an emerging nutraceutical compound present in plants and animal foods, is an endogenous PPAR-α agonist with well-demonstrated anti-inflammatory and analgesics characteristics. In this model of mice varicocele, PPAR-α and TLR4 receptors’ roles were investigated through the administration of ultra-micronized PEA (PEA-um). Male wild-type (WT), PPAR-α knockout (KO), and TLR4 KO mice were used. A group underwent sham operation and administration of vehicle or PEA-um (10 mg/kg i.p.) for 21 days. Another group (WT, PPAR-α KO, and TLR4 KO) underwent surgical varicocele and was treated with vehicle or PEA-um (10 mg/kg i.p.) for 21 days. At the end of treatments, all animals were euthanized. Both operated and contralateral testes were processed for histological and morphometric assessment, for PPAR-α, TLR4, occludin, and claudin-11 immunohistochemistry and for PPAR-α, TLR4, transforming growth factor-beta3 (TGF-β3), phospho-extracellular signal-Regulated-Kinase (p-ERK) 1/2, and nucleotide-binding oligomerization domain-like receptor (NLR) family pyrin domain-containing 3 (NLRP3) Western blot analysis. Collectively, our data showed that administration of PEA-um revealed a key role of PPAR-α and TLR4 in varicocele pathophysiology, unmasking new nutraceutical therapeutic targets for future varicocele research and supporting surgical management of male infertility.  相似文献   
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