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1.
Zhonghua Yi Xue Za Zhi ; 103(3): 186-191, 2023 Jan 17.
Artículo en Chino | MEDLINE | ID: mdl-36649989

RESUMEN

Objective: To construct and analyze the functional network changes of hemi-brain in patients with brain tumor before and after anesthesia by using resting state functional magnetic resonance imaging (rs-fMRI). Methods: A total of 18 right-handed patients were prospectively included (6 males and 12 females). The patients underwent glioma resection in Peking University International Hospital from December 2018 to December 2021, and age ranged from 20 to 65 (45.1±13.6) years, with American Society of Anesthesiologists (ASA) grade of Ⅰ-Ⅱ. MRI scans were performed while the patient was awake and at the depth of surgical anesthesia. The functional network of healthy lateral brain was constructed and analyzed by means of graph theory, and its global and local topological properties were calculated. Global topology attributes included global efficiency (Eg), local efficiency (Eloc), clustering parameters (Cp), length parameter of shortest path (Lp), and small world (SW). Topology attributes of nodes included node degree (ND), node efficiency (NE) and between centrality (BC). The global and nodal topological properties of the hemi-brain network were compared between patients with different hemispherical space occupying under wakefulness and anesthesia. Results: At the awake state, Eloc and Cp in the global topological attributes of hemi-brain network were 0.259±0.007 and 0.197±0.010, respectively, and decreased to 0.242±0.013 and 0.177±0.021, respectively after anesthesia, with statistically significant differences (all P<0.01). The topological attributes of the nodes in hemi-side brain showed that ND, NE and BC were increased in the default mode network-related brain regions, while NE and BC were decreased in the limbic system and subcortical structures. Eloc and Cp were 0.258±0.008 and 0.198±0.008 respectively in the patients with left hemisphere space occupying, and decreased to 0.241±0.011 and 0.177±0.015 respectively after anesthesia, with statistically significant differences (all P<0.01). However, only Eloc decreased in patients with right hemisphere space occupying after anesthesia, and Eloc was 0.260±0.006 and 0.243±0.016 respectively when awake and after anesthesia, with statistically significant differences (P<0.05). The topological attributes of nodes in patients with space occupying in different cerebral hemispheres showed bidirectional changes after anesthesia, and patients with space occupying in the left cerebral hemisphere were more likely to be widely affected after anesthesia. The effects of anesthetic drugs may show hemispheric laterality. If the tumor was in the dominant hemisphere, the compensatory function of the dominant side was more likely to be damaged. Conclusions: During anesthesia-induced loss of consciousness in patients with brain tumors, both the ability to integrate information and the functional connections between local regions are weakened, and some brain regions have functional connection reorganization. The changes of brain network after anesthesia are bidirectional regulation.


Asunto(s)
Anestesia , Neoplasias Encefálicas , Masculino , Femenino , Humanos , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Mapeo Encefálico/métodos , Encéfalo , Imagen por Resonancia Magnética/métodos
2.
J Dairy Sci ; 106(2): 884-896, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36460506

RESUMEN

Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus are the main species used for yogurt preparation. Glutathione (GSH) can be synthesized by S. thermophilus and plays a crucial role in combating environmental stress. However, the effect of GSH biosynthesis by S. thermophilus on cocultured L. delbrueckii ssp. bulgaricus is still unknown. In this study, a mutant S. thermophilus ΔgshF was constructed by deleting the GSH synthase. The wild strain S. thermophilus ST-1 and ΔgshF mutants were cocultured with L. delbrueckii ssp. bulgaricus ATCC11842 by using Transwell chambers (Guangzhou Shuopu Biotechnology Co., Ltd.), respectively. It was proven that the GSH synthesized by S. thermophilus ST-1 could be absorbed and used by L. delbrueckii ssp. bulgaricus ATCC11842, and promote growth ability and stress tolerance of L. delbrueckii ssp. bulgaricus ATCC11842. The biomass of L. delbrueckii ssp. bulgaricus ATCC11842 cocultured with S. thermophilus ST-1 or ΔgshF (adding exogenous GSH) increased by 1.8 and 1.4 times compared with the biomass of L. delbrueckii ssp. bulgaricus ATCC11842 cocultured with S. thermophilus ΔgshF. Meanwhile, after H2O2 and low-temperature treatments, the bacterial viability of L. delbrueckii ssp. bulgaricus cocultured with S. thermophilus ΔgshF, with or without GSH, was decreased by 41 and 15% compared with that of L. delbrueckii ssp. bulgaricus cocultured with S. thermophilus ST-1. Furthermore, transcriptome analysis showed that the expression levels of genes involved in purine nucleotide and pyrimidine nucleotide metabolism in L. delbrueckii ssp. bulgaricus ATCC11842 were at least 3 times increased when cocultured with S. thermophilus (fold change > 3.0). Moreover, compared with the mutant strain ΔgshF, the wild-type strain ST-1 could shorten the fermented curd time by 5.3 hours during yogurt preparation. These results indicated that the GSH synthesized by S. thermophilus during cocultivation effectively enhanced the activity of L. delbrueckii ssp. bulgaricus and significantly improved the quality of fermented milk.


Asunto(s)
Lactobacillus delbrueckii , Animales , Lactobacillus delbrueckii/metabolismo , Streptococcus thermophilus/metabolismo , Técnicas de Cocultivo/veterinaria , Peróxido de Hidrógeno/metabolismo , Yogur/análisis , Glutatión/metabolismo , Fermentación
3.
J Dairy Sci ; 104(4): 3990-4001, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33589257

RESUMEN

Streptococcus thermophilus is widely used as a starter culture in the fermentation of yogurt. Glutathione (GSH; γ-glutamyl-cysteinyl-glycine), as a tripeptide, has an important physiological role for Strep. thermophilus. However, the scope of the GSH transport proteins is still unexplored in this species. In the present study, 5 peptide transporter-related proteins (Ptrp) of Strep. thermophilus strain ST-1 were selected and then inactivated by gene insertion, respectively. Through detection and comparison of intracellular GSH content of mutant strain and wild strain, we identified 2 proteins, named Ptrp-2 and Ptrp-4, that might be related to GSH transport. Reverse-transcriptase quantitative PCR was performed to verify the gene expressions of these 2 possible GSH transport-related proteins, and it was finally determined that Ptrp-2 plays an important role in GSH transport of Strep. thermophilus. Milk fermentation experiments were further conducted to test the effect of Ptrp-2 on the characteristics of yogurt. The results showed that the fermented milk hardly curds using the mutant strain, indicating that Ptrp-2 is important for Strep. thermophilus as a yogurt starter.


Asunto(s)
Streptococcus thermophilus , Yogur , Animales , Proteínas Portadoras , Fermentación , Glutatión , Proteínas de Transporte de Membrana , Leche , Streptococcus thermophilus/genética
4.
Beijing Da Xue Xue Bao Yi Xue Ban ; 51(5): 824-828, 2019 Oct 18.
Artículo en Chino | MEDLINE | ID: mdl-31624384

RESUMEN

OBJECTIVE: To summarize the clinical, video electroencephalogram (VEEG), radiological and pathological features of 3 patients of temporal lobe epilepsy (TLE) with amygdala enlargement (AE). METHODS: Three TLE patients with AE who were hospitalized in Peking University International Hospital were collected. The above features were retrospectively analyzed, and the amygdala volume was measured as well. RESULTS: Of all the 3 patients, 2 were females and 1 male, whose seizure onset ages varied from 21 to 40 years. Two cases presented with secondarily generalized tonicclonic seizures after falling asleep during the night. One of the 2 cases had complex partial seizures (CPSs) with episodic memory and automatism after one year, and the third one had CPSs with lip smacking and tongue wagging during the night. All the patients suffered from obvious anxious disorder. Unilateral AE by MRI was demonstrated in the 3 cases, one on the right side, and the other two on the left side. The average amygdala volume of the enlarged side and the other side were (2 123.7±131.8) mm3 and (1 276.3±156.9) mm3, respectively. Unilateral interictal epileptic discharges were ipsilateral to the AE in 2 cases, while the other patient showed bilateral interictal epileptic discharges. The ictal VEEG showed that the seizure onset zone was ipsilateral to the AE and was confined to the anterior and middle temporal regions in the 3 patients. The interictal single-photon emission computed tomography (SPECT) was negative in 2 cases. The interictal positron emission tomography (PET) showed hypometabolism in the AE in one case. The histological pathology revealed focal cortical dysplasia in the amygdala and temporal lobe in the 3 cases, and one of the 3 cases was combined with hippocampal sclerosis. All the patients became seizure free after surgery in the half year following-up. VEEG revealed slow wave activity and occasional spike wave in the operated side. CONCLUSION: AE may be one subtype of TLE. It is necessary to recognize AE in TLE with MRI-negative. For those poorly responsive to antiepileptic drugs, surgical treatment could provide a better solution. Focal cortical dysplasia may be one of the most common pathological features of TLE with AE.


Asunto(s)
Amígdala del Cerebelo , Epilepsia del Lóbulo Temporal , Adulto , Electroencefalografía , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Estudios Retrospectivos , Lóbulo Temporal , Adulto Joven
6.
Vet Parasitol ; 241: 52-60, 2017 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-28579032

RESUMEN

A great deal of evidence demonstrates that a strongly clonal population structure of Toxoplasma gondii strains exists in humans and animals in North America and Europe, while the strains from South America are genetically separate and more diverse. Potential differences in virulence between different strains mean that an understanding of strain diversity is important to human and animal health. However, to date, only one predominant genotype, ToxoDB#9 (Chinese I), and a few other genotypes, including ToxoDB#205, have been identified in China. By using DNA sequence-based phylogenetic analyses, we have re-evaluated the population structure of T. gondii strains collected from China and compared them with other global strains. Based on phylogenetic analysis of restriction fragment length polymorphisms, multilocus sequence typing and intron sequences from T. gondii, we propose that the Chinese isolates described as Chinese I are divided into two groups called Chinese I and Chinese III. Our results demonstrate that significant differences were found in mouse mortality caused by some Chinese strains, and also the archetypal I, II, III strains in mice. Furthermore, a comparison of cyst loading in the brains of infected rats showed some Chinese strains to be capable of a high degree of cyst formation. Furthermore we show that genotyping using neutral genetic markers may not be a useful predictor of pathogenic phenotypes.


Asunto(s)
Genotipo , Toxoplasma/genética , Toxoplasma/patogenicidad , Toxoplasmosis Animal/parasitología , Animales , China/epidemiología , Femenino , Ratones , Filogenia , Polimorfismo Genético , Toxoplasmosis Animal/epidemiología , Virulencia
7.
Hum Exp Toxicol ; 35(5): 511-25, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26205530

RESUMEN

The purpose of the present study is to establish a new animal model of azithromycin (AZ)-induced liver injury and study the molecular pathological change during the process. First, mice were respectively injected intraperitoneally with AZ of different high doses. Our results showed that 800 mg/kg AZ injection significantly induced liver injury in the mice, which reflected an ideal process of liver injury and repair. In this study, we analyzed the molecular pathological changes during the process by hematoxylin and eosin staining, immunohistochemistry, Western blot, and quantitative real-time reverse transcription polymerase chain reaction in the liver of mice at 0, 12, 24, 48, and 72 h after 800 mg/kg injection. Our results showed that the expression of heat shock protein 70, proliferating cell nuclear antigen, vascular endothelial growth factor, caspase 3, and cytochrome P450 2E1 were significantly differently expressed during liver injury induced by 800 mg/kg AZ in mice. Our results will be conducive for further study of the pathogenesis and prevention of drug-induced liver injury.


Asunto(s)
Antibacterianos/toxicidad , Apoptosis/efectos de los fármacos , Azitromicina/toxicidad , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Modelos Animales de Enfermedad , Expresión Génica/efectos de los fármacos , Animales , Western Blotting , Caspasa 3/genética , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Citocromo P-450 CYP2E1/genética , Relación Dosis-Respuesta a Droga , Proteínas HSP70 de Choque Térmico/genética , Inmunohistoquímica , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Masculino , Ratones Endogámicos BALB C , Antígeno Nuclear de Célula en Proliferación/genética , Factor A de Crecimiento Endotelial Vascular/genética
8.
Hum Exp Toxicol ; 34(11): 1053-72, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25585999

RESUMEN

This study focuses on investigating the concrete role of a disintegrin and metalloproteinase 8 (ADAM8) in the progression of hepatocellular carcinoma (HCC). Mice received anti-ADAM8 monoclonal antibody (mAb) of 100 µg/100 µl, 200 µg/100 µl or 300 µg/100 µl, respectively, in phosphate-buffered saline (PBS) or PBS intervention during the progression of HCC induced by diethylnitrosamine. The survival rate, body weight, and relative liver weight were determined in the mice. Serum aspartate aminotransferase (AST), alanine aminotransferase (ALT) and α-fetoprotein (AFP) level, hematoxylin-eosin staining, the expression level of vascular endothelial growth factor A (VEGF-A), proliferating cell nuclear antigen (PCNA), caspase 3 (Casp3), B cell leukemia 2 (Bcl2), B cell leukemia 2-associated X protein (Bax), protein p53 (P53), and ADAM8 were detected in the mice at the end of the 24th week. Our results showed that anti-ADAM8 mAb intervention effectively improved the survival rate, reduced the body weight loss and increased the relative liver weight in mice in a dose-dependent manner (p < 0.05 or p < 0.01). Anti-ADAM8 mAb intervention also significantly lowered serum AST, ALT, and AFP levels (p < 0.05 or p < 0.01), slowed the progression of HCC (p < 0.05 or p < 0.01), induced the expression of Casp3, Bax, and P53 (p < 0.05 or p < 0.01), and inhibited the expression of VEGF-A, PCNA, and Bcl2 in the liver of mice (p < 0.05 or p < 0.01) in a dose-dependent manner compared with the mice receiving PBS intervention. Our study suggested that ADAM8 might promote the progression of HCC by regulating the expression of these factors. Anti-ADAM8 mAb intervention might be suitable as a potential method for HCC therapy.


Asunto(s)
Proteínas ADAM/metabolismo , Antígenos CD/metabolismo , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas ADAM/inmunología , Alanina Transaminasa/sangre , Animales , Anticuerpos Monoclonales/farmacología , Antígenos CD/inmunología , Aspartato Aminotransferasas/sangre , Carcinoma Hepatocelular/patología , Caspasa 3/genética , Caspasa 3/metabolismo , Dietilnitrosamina , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Neoplasias Hepáticas/patología , Masculino , Proteínas de la Membrana/inmunología , Ratones Endogámicos BALB C , Antígeno Nuclear de Célula en Proliferación/genética , Antígeno Nuclear de Célula en Proliferación/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo , alfa-Fetoproteínas/análisis , Proteína X Asociada a bcl-2/metabolismo
9.
Neoplasma ; 60(2): 209-14, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23259791

RESUMEN

In order to present our experience with 10 cases of renal epithelioid angiomyolipoma (EAML) and validate the applicability of Ki-67 (proliferation marker) for EAML, we reviewed medical records of 10 consecutive cases diagnosed EAML from January 2005 to February 2012 at our department. Clinical data were collected and analyzed and pathology slides were reviewed. The immunohistochemical reactions for Ki-67 were performed and tumors showed positive expression were estimated. Active follow-up was performed to investigate the association between Ki-67 expression and the prognosis. The mean age and tumor size of the patients was 43.6 years (range 32-56) and 8.2 cm (range 2-15 cm), respectively. Seven were females while three were males. Radical nephrectomy was performed in 6 patients, partial nephrectomy in 3, and renal artery ligation in 1. The immunohistochemical reactions for HMB-45 (Human Melanoma Black), SMA (Smooth Muscle Actin) were positive but for S-100 were negative. The number of patients showing positive/negative Ki-67 expression was 5/5. The survival rate of the positive group was 20% (1/5) while 100% (5/5) of the negative group during the median follow-up time of 26.75 months (range 1-53). Recurrence, metastasis and death due to disease occurred in 1 (10%), 3 (30%) and 4 (40%) patients, respectively. Higher expression (positive) of Ki-67 indicates the presence of EAML and poor prognosis of patients. Surgical excision including radical and partial nephrectomy is a considerable approach to the treatment for its malignant potential.


Asunto(s)
Angiomiolipoma/patología , Células Epitelioides/patología , Antígeno Ki-67/análisis , Neoplasias Renales/patología , Adulto , Angiomiolipoma/cirugía , Biomarcadores , Femenino , Humanos , Inmunohistoquímica , Neoplasias Renales/cirugía , Masculino , Persona de Mediana Edad , Nefrectomía , Pronóstico
10.
J Biol Chem ; 271(34): 20845-52, 1996 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-8702840

RESUMEN

Neurofilaments, the major intermediate filaments in large myelinated neurons, are essential for specifying proper axonal caliber. Mammalian neurofilaments are obligate heteropolymers assembled from three polypeptides, neurofilament (NF)-H, NF-M, and NF-L, each of which undergoes phosphorylation at multiple sites. NF-M and NF-L are known to be modified by O-linked N-acetylglucosamine (O-GlcNAc) (Dong, D. L.-Y., Xu, Z.-S., Chevrier, M. R., Cotter, R. J., Cleveland, D. W., and Hart, G. W. (1993) J. Biol. Chem. 268, 16679-16687). Here we further report that NF-H is extensively modified by O-GlcNAc at Thr53, Ser54, and Ser56 in the head domain and, somewhat surprisingly, at multiple sites within the Lys-Ser-Pro repeat motif in the tail domain, a region in assembled neurofilaments known to be nearly stoichiometrically phosphorylated on each of the approximately 50 KSP repeats. Beyond the earlier identified sites on NF-M and NF-L, O-GlcNAc sites on Thr19 and Ser34 of NF-M and Ser34 and Ser48 of NF-L are also determined here, all of which are localized in head domain sequences critical for filament assembly. The proximity of O-GlcNAc and phosphorylation sites in both head and tail domains of each subunit indicates that these modifications may influence one another and play a role in filament assembly and network formation.


Asunto(s)
Acetilglucosamina/metabolismo , Proteínas de Neurofilamentos/metabolismo , Secuencia de Aminoácidos , Animales , Glicopéptidos/química , Glicosilación , Masculino , Datos de Secuencia Molecular , Proteínas del Tejido Nervioso/química , Proteínas de Neurofilamentos/química , Mapeo Peptídico , Procesamiento Proteico-Postraduccional , Ratas , Secuencias Repetitivas de Ácidos Nucleicos , Serina/química , Médula Espinal/química
11.
Shi Yan Sheng Wu Xue Bao ; 28(3): 241-6, 1995 Sep.
Artículo en Chino | MEDLINE | ID: mdl-8571707

RESUMEN

We have previously reported that the malignant phenotype of human liver carcinoma cell line BEL-7404 was reversed by antisense EGFR RNA. The aim of this paper is to explore the effects of an oligomer targeted to mRNA for EGFR and growth of BEL-7404 cells. A 21-mer oligodeoxynucleotides (ODNs) complementary to the 5' initiation region of mRNA for EGFR was synthesized and added to medium. The results showed that the growth of BEL-7404 cells was inhibited by ODNs at concentration of 3.2 mumol/L. Inhibition of DNA synthesis of BEL-7404 cells was dose-dependent and reached to 62.1% at 3.2 mumol/L as measured by 3H-thymidine incorporation test. The inhibition of EGFR gene transcription of the cells was up to 10.5% and 14.3% respectively after incubation with ODNs by 5 and 24 hours as measured by densitometric scanning of dot (RNA) blots of EGFR. The EGFR protein (P 170) expression was also found to be blocked by 4 days' antisense oligomer treatment up to 37.4% as measured by densitometric scanning of specific band of Western blot. The oligonucleotide phosphorothioate (S-ODNs) complementary to the same region of the gene was also synthesized and its growth inhibition effects on BEL-7404 cells were compared with those of unmodified oligomers. ODNs attained their highest effect within 30 hours. The proliferation inhibition rate of the cells didn't increase when cells were cultured in serum free medium. In contrast, the S-ODNs induced inhibition reached comparable level after 96 hours treatment as measured by 3H-thymidine uptake and the effect lasted longer, 1 mumol/L S-ODNs showed a little effect on BEL-7404 cells' proliferation. We concluded that the antisense oligomers directed to mRNA for EG-FR could inhibit the BEL-7404 cells growth by blocking the EGFR gene expression in some degree and the phosphorothioate analogues were more stable than the unmodified ODNs in vitro.


Asunto(s)
Antineoplásicos/farmacología , Carcinoma Hepatocelular/patología , Receptores ErbB/genética , Neoplasias Hepáticas/patología , Oligonucleótidos Antisentido/farmacología , Animales , Secuencia de Bases , División Celular/efectos de los fármacos , Expresión Génica , Humanos , Datos de Secuencia Molecular , Tionucleótidos/farmacología , Células Tumorales Cultivadas/efectos de los fármacos , Células Tumorales Cultivadas/metabolismo
12.
J Biol Chem ; 270(7): 3234-8, 1995 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-7852409

RESUMEN

Mutations in superoxide dismutase 1 (SOD1) have been linked to familial amyotrophic lateral sclerosis, a dominantly inherited motor neuron disorder of midlife. Because SOD1 is a homodimeric enzyme, dimerization of mutant and wild-type SOD1 subunits could dominantly alter the activity, stability, or localization of wild-type SOD1 subunits. To explore these possibilities, we used transient and stable gene transfection to express high levels of either of two mutant human SOD1 subunits in the presence of limited levels of wild-type mouse and/or human SOD1 subunits. Although both mutant subunits displayed diminished half-lives and free radical scavenging activities, their presence caused no change in the half-life or activity of wild-type SOD1 subunits. Our data indicate that mutant subunits do not dominantly affect the function of wild-type SOD1 subunits. These findings, together with observations that many mutant SOD1 subunits retain significant stability and activity, suggest that motor neuron damage in familial amyotrophic lateral sclerosis is caused by the acquisition of injurious properties by mutant SOD1 subunits.


Asunto(s)
Esclerosis Amiotrófica Lateral/enzimología , Esclerosis Amiotrófica Lateral/genética , Mutación Puntual , Superóxido Dismutasa/genética , Superóxido Dismutasa/metabolismo , Adulto , Secuencia de Aminoácidos , Animales , Línea Celular , Chlorocebus aethiops , Expresión Génica , Humanos , Riñón , Cinética , Sustancias Macromoleculares , Ratones , Persona de Mediana Edad , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Neuroblastoma , Reacción en Cadena de la Polimerasa , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/metabolismo , Superóxido Dismutasa/biosíntesis , Transcripción Genética , Transfección
13.
Proc Natl Acad Sci U S A ; 91(17): 8292-6, 1994 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-8058797

RESUMEN

Familial amyotrophic lateral sclerosis (FALS) has been linked to mutations in the homodimeric enzyme Cu/Zn superoxide dismutase 1 (SOD1). Assay by transient expression in primate cells of six FALS mutant enzymes revealed a continuum of enzymatic activity bounded by the enzyme carrying the mutation Gly-85-->Arg, which was inactive, and mutant enzyme G37R carrying the Gly-37-->Arg change, which retained full specific activity but displayed a 2-fold reduction in polypeptide stability. The G37R mutant displayed similar properties in transformed lymphocytes from an individual heterozygous for the G37R and wild-type SOD1 genes; heterodimeric enzymes composed of mutant and wild-type subunits were detected, but there was no measurable diminution in the stability and activity of the wild-type subunits. Thus, for mutants such as G37R, either surprisingly modest losses in activity (involving only the mutant subunit) can yield motor neuron death, or alternatively, mutant SOD1 may acquire properties that injure motor neurons by one or more mechanisms unrelated to the metabolism of oxygen radicals.


Asunto(s)
Esclerosis Amiotrófica Lateral/genética , Mutación Puntual , Superóxido Dismutasa/genética , Secuencia de Aminoácidos , Esclerosis Amiotrófica Lateral/enzimología , Arginina , Secuencia de Bases , Línea Celular , Clonación Molecular , Secuencia de Consenso , Cisteína/metabolismo , Cartilla de ADN , Tamización de Portadores Genéticos , Ligamiento Genético , Glicina , Humanos , Isoenzimas/biosíntesis , Isoenzimas/genética , Isoenzimas/metabolismo , Cinética , Linfocitos , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Reacción en Cadena de la Polimerasa , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/metabolismo , Superóxido Dismutasa/biosíntesis , Superóxido Dismutasa/metabolismo
14.
J Biol Chem ; 268(22): 16679-87, 1993 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-8344946

RESUMEN

Neurofilaments are neuronal intermediate filaments that play an important role in the growth and maintenance of large myelinated axons. Mammalian neurofilaments are composed of three polypeptide subunits, designed as NF-L, NF-M, and NF-H, all of which are phosphorylated. Here, we demonstrate by several criteria that neurofilament polypeptides are also modified by an abundant type of intracellular protein glycosylation in which single N-acetylglucosamine monosaccharides are O-glycosidically (O-GlcNAc) linked to serine or threonine residues. In purified neurofilament proteins, the O-GlcNAc modifications occur at a stoichiometry of approximately 0.1 and 0.15 mol of GlcNAc/mol of NF-L and NF-M, respectively. The predominant sites of O-GlcNAc attachment on NF-L and NF-M are identified using proteolysis, purification of the glycopeptides, and subsequent analysis by automated gas-phase sequencing, manual Edman degradation, and laser desorption mass spectrometry. For NF-L, both major sites of glycosylation (Thr21 and Ser27) are located at the NH2-terminal head domain. For NF-M, one major site (Thr48) lies within the NH2-terminal head domain, whereas the other (Thr431) is located at the tail domain. Deletions encompassing these sites have been shown previously to have a dominant detrimental effect upon neurofilament assembly, raising questions about the specific function(s) of the saccharide moieties at these sites. Specific identification of these O-GlcNAc attachment sites has set the stage for more detailed mutagenic analysis of O-GlcNAc functions on neurofilaments.


Asunto(s)
Acetilglucosamina/metabolismo , Proteínas de Neurofilamentos/metabolismo , Secuencia de Aminoácidos , Animales , Bovinos , Electroforesis en Gel de Poliacrilamida , Glicosilación , Humanos , Espectrometría de Masas , Datos de Secuencia Molecular , Mapeo Peptídico , Ratas , Homología de Secuencia de Aminoácido
15.
J Biol Chem ; 267(7): 4467-71, 1992 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-1537832

RESUMEN

The COOH-terminal tail domain of the neurofilament polypeptide M from rat nervous tissue contains approximately six molecules of phosphate. We report here that protein kinases in a crude cytoskeleton preparation of rat nervous tissue phosphorylated a set of tryptic peptides of M similar (but not identical) to those phosphorylated by living dorsal root ganglion cells in culture. Using these phosphopeptides as markers, we purified these same peptides from rat spinal cord and identified six specific phosphorylation sites in M by enzymatic and chemical criteria. These sites, serines 502, 506, 536, 606, 608, and 666, are all located in the COOH-terminal tail domain. Four are embedded in the repeated motif KSP whereas two are within variants of this motif, KSD and ESP. All of the sites that were preceded by lysine were resistant to alkaline phosphatase prior to modification of the lysine with citraconic anhydride. The identification of these sites should aid in investigations of the function of the phosphorylation of this protein and provides criteria for identifying the relevant kinases.


Asunto(s)
Proteínas de Neurofilamentos/metabolismo , Secuencia de Aminoácidos , Animales , Citoesqueleto/enzimología , Ganglios Espinales/metabolismo , Datos de Secuencia Molecular , Mapeo Peptídico , Fosforilación , Proteínas Quinasas/metabolismo , Ratas , Médula Espinal/citología , Médula Espinal/enzimología , Tripsina/metabolismo
16.
J Neurosci ; 10(6): 1838-46, 1990 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2162386

RESUMEN

Neurofilaments are composed of 3 polypeptides designated NF-H, NF-M, and NF-L, all of which are subject to posttranslational phosphorylation. It has been suggested that phosphorylation of the NF-L polypeptide can influence the assembly of NF-L into filaments, but the sites at which NF-L is phosphorylated are unknown. To locate these phosphorylation sites, we have identified phosphopeptides of NF-L by labeling them with 32P both in vitro and in cultured neurons and also by observing their change in chromatographic behavior after they have been treated with phosphatase. We report here that serine 473, in the carboxy-terminal tail domain of NF-L, is a major substrate in vitro for protein kinases endogenous to a crude cytoskeleton-containing fraction. Moreover, serine 473 is a major phosphorylation site in vivo; in neurofilaments isolated from rat spinal cord, approximately 73% of serine 473 was phosphorylated, and accounted for at least one-third of the total phosphate associated with NF-L. The identification of this phosphorylation site in NF-L provides a criterion for identifying the protein kinase that phosphorylates NF-L and raises the question of its function.


Asunto(s)
Proteínas de Filamentos Intermediarios/metabolismo , Proteínas de Neurofilamentos , Animales , Técnicas de Cultivo , Citoesqueleto/enzimología , Ganglios Espinales , Péptidos/metabolismo , Fosfatos/metabolismo , Monoéster Fosfórico Hidrolasas/metabolismo , Fosforilación , Proteínas Quinasas/metabolismo , Ratas , Serina/metabolismo , Médula Espinal/metabolismo
17.
Arzneimittelforschung ; 34(9B): 1203-4, 1984.
Artículo en Inglés | MEDLINE | ID: mdl-6542394

RESUMEN

40 patients infected with P. westermani were divided into 3 groups and treated with praziquantel (2-cyclohexylcarbonyl-1,2,3,6,7,11b-hexahydro-4H-pyrazino[2,1-a]++ +isoquinolin- 4-one) by 3 different dosages. Parasitological cure was achieved in 27/40 patients, i.e. 67.5%. Details are given in this short communication.


Asunto(s)
Enfermedades de los Gatos/tratamiento farmacológico , Isoquinolinas/uso terapéutico , Paragonimiasis/tratamiento farmacológico , Praziquantel/uso terapéutico , Animales , Enfermedades de los Gatos/parasitología , Gatos , Humanos , Paragonimiasis/veterinaria , Praziquantel/efectos adversos
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