RESUMEN
Streptococcal toxic shock syndrome (STSS) is a severe invasive infection characterized by the sudden onset of shock, multiorgan failure, and high mortality. Although STSS is mainly caused by Streptococcus pyogenes, group G streptococcus identified as S. dysgalactiae subsp. equisimilis (SDSE) causing STSS has also been reported; however, no study has analyzed >100 isolates of SDSE causing STSS. Therefore, we characterized the emm genotype of 173 SDSE isolates obtained from STSS patients in Japan during 2014-2016 and performed antimicrobial susceptibility testing using the broth microdilution method and emm gene typing. The predominant emm genotype was found to be stG6792, followed by stG485, stG245, stG10, stG6, and stG2078. These six genotypes constituted more than 75% of the STSS isolates. The proportion of each emm genotype in STSS isolates correlated with that in invasive isolates previously reported. We found that 16.2% of the isolates showed clindamycin resistance. The proportion of clindamycin-resistant SDSE isolates was significantly higher than that of S. pyogenes isolates. Thus, while treating STSS caused by SDSE, it is necessary to consider the possibility of clindamycin resistance and to ensure judicious use of the drug.
Asunto(s)
Farmacorresistencia Bacteriana , Choque Séptico/microbiología , Infecciones Estreptocócicas/microbiología , Streptococcus pyogenes , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/uso terapéutico , Antígenos Bacterianos/genética , Proteínas de la Membrana Bacteriana Externa/genética , Proteínas Portadoras/genética , Clindamicina/uso terapéutico , Femenino , Técnicas de Genotipaje , Humanos , Japón/epidemiología , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Choque Séptico/tratamiento farmacológico , Choque Séptico/epidemiología , Infecciones Estreptocócicas/tratamiento farmacológico , Infecciones Estreptocócicas/epidemiología , Streptococcus pyogenes/clasificación , Streptococcus pyogenes/efectos de los fármacos , Streptococcus pyogenes/genética , Streptococcus pyogenes/aislamiento & purificaciónRESUMEN
Bruxism contributes to the development of temporomandibular disorders as well as causes dental problems. Although it is an important issue in clinical dentistry, no treatment approaches have been proven effective. This study aimed to use electromyogram (EMG) biofeedback (BF) training to improve awake bruxism (AB) and examine its effect on sleep bruxism (SB). Twelve male participants (mean age, 26·8 ± 2·5 years) with subjective symptoms of AB or a diagnosis of SB were randomly divided into BF (n = 7) and control (CO, n = 5) groups to undergo 5-h daytime and night-time EMG measurements for three consecutive weeks. EMG electrodes were placed over the temporalis muscle on the habitual masticatory side. Those in the BF group underwent BF training to remind them of the occurrence of undesirable clenching activity when excessive EMG activity of certain burst duration was generated in week 2. Then, EMGs were recorded at week 3 as the post-BF test. Those in the CO group underwent EMG measurement without any EMG BF training throughout the study period. Although the number of tonic EMG events did not show statistically significant differences among weeks 1-3 in the CO group, events in weeks 2 and 3 decreased significantly compared with those in week 1, both daytime and night-time, in the BF group (P < 0·05, Scheffé's test). This study results suggest that EMG BF to improve AB tonic EMG events can also provide an effective approach to regulate SB tonic EMG events.
Asunto(s)
Biorretroalimentación Psicológica/métodos , Bruxismo/terapia , Electromiografía , Dolor Facial/etiología , Dolor Facial/prevención & control , Músculos Masticadores/fisiopatología , Trastornos de la Articulación Temporomandibular/etiología , Adulto , Bruxismo/complicaciones , Bruxismo/psicología , Humanos , Masculino , Contracción Muscular , Dimensión del Dolor , Trastornos de la Articulación Temporomandibular/prevención & controlRESUMEN
UNLABELLED: Unipedal standing time was shorter and bone mineral density was lower in Japanese women aged 50 years and over with low-energy distal radius fractures resulting from falls than those in age-matched community-dwelling Japanese women without distal radius fractures. INTRODUCTION: The aim of this study was to compare unipedal standing time and bone mineral density (BMD) of women >or=50 years of age with distal radius fractures with those of age-matched women without fractures. METHODS: Fracture group was 54 Japanese women with low-energy distal radius fractures resulting from fall. Non-fracture group was 52 community-dwelling Japanese women without fractures. Unipedal standing time and BMD were measured. RESULTS: There were no significant differences in age and body mass index between the two groups. The percentage of women with unipedal standing time <15 s was 44.4% in the fracture group and 13.5% in the non-fracture group, while the respective frequencies for >120 s were 20.4% and 50.0%. The T-score of BMD was significantly lower in the fracture than non-fracture group. Logistic regression analysis identified unipedal standing time <15 s and T-score <70% as significant factors associated with distal radius fractures. Notably, T-score <70% was significant in subjects <65 years, and unipedal standing time <15 s was significant in those >or=65 years. CONCLUSION: Unipedal standing time was shorter and BMD was lower in women >or=50 years of age with distal radius fractures than those in age-matched women without fractures.
Asunto(s)
Fracturas Osteoporóticas/etiología , Equilibrio Postural/fisiología , Fracturas del Radio/etiología , Accidentes por Caídas , Adulto , Anciano , Antropometría , Densidad Ósea/fisiología , Métodos Epidemiológicos , Femenino , Humanos , Persona de Mediana Edad , Osteoporosis Posmenopáusica/complicaciones , Osteoporosis Posmenopáusica/fisiopatología , Fracturas Osteoporóticas/fisiopatología , Fracturas del Radio/fisiopatología , Factores de TiempoRESUMEN
It is expected that the three-dimensional atom probe (3DAP) will be used as a tool to visualize the atomic scale of hydrogen atoms in steel is expected, due to its high spatial resolution and very low detection limit. In this paper, the first 3DAP analysis of titanium hydride precipitates in metal titanium is reported in terms of the quantitative detection of hydrogen. FIB fabrication techniques using the lift-out method have enabled the production of needle tips of hydride precipitates, of several tens of microns in size, within a titanium matrix. The hydrogen concentration estimated from 3DAP analysis was slightly smaller than that of the hydride phase predicted from the phase diagram. We discuss the origin of the difference between the experimental and predicted values and the performance of 3DAP for the quantitative detection of hydrogen.
RESUMEN
The aim of this study was to investigate the expression of tumour endothelial marker 8 (TEM8) in canine mammary gland tumours (MGTs) by immunohistochemistry and to evaluate the association between tumour cell TEM8 expression and tumour histological features, histological grades and expression of luminal and basal/myoepithelial cell markers. TEM8 expression was detected in >60 % of neoplastic epithelial cells in all simple adenomas (n = 25), simple carcinomas (n = 43) and invasive micropapillary carcinomas (n = 5) studied. Six of the 18 solid carcinomas studied showed TEM8 expression in >60% of carcinoma cells present in solid structures and in 12 of the 18 solid carcinomas, <30% of the luminal structure-forming carcinoma cells showed TEM8 expression. TEM8 expression in the neoplastic cells was not associated with histological malignancy in canine MGTs. TEM8+ tumour cells frequently showed the luminal-like phenotype cytokeratin (CK)19+/p63-/α-smooth muscle actin (SMA)-, while most TEM8- tumour cells exhibited the basal-like phenotype CK19-/p63+/αSMA-. These findings indicate that TEM8 may be involved in maintaining the characteristics of luminal cells in canine MGTs and that TEM8 would be useful in identifying the type of neoplastic epithelial cell in MGTs.
Asunto(s)
Adenocarcinoma/veterinaria , Adenoma/veterinaria , Enfermedades de los Perros/patología , Neoplasias Mamarias Animales/patología , Receptores de Péptidos/biosíntesis , Animales , Biomarcadores de Tumor/análisis , Enfermedades de los Perros/metabolismo , Perros , Femenino , Neoplasias Mamarias Animales/metabolismo , Receptores de Péptidos/análisisRESUMEN
BACKGROUND: The gene knockout technique is important in xenotransplantation research. Herein we have described the molecular cloning of two genes that are candidates to overcome the poor rate of homologous recombination. METHODS: Candidate cDNA fragments were amplified by polymerase chain reaction (PCR) with the corresponding primer sets deduced from a multiple alignment analysis of other mammalian genes from a cDNA library prepared from pig spleen tissue. To obtain the full-length cDNA, a 5'- and 3'-RACE PCR experiments was performed. RESULTS: We successfully isolated the cDNA sequences of two pig genes--BLM, a Bloom's syndrome-related gene, and UBL-1/SUMO-1--which are closely related to homologous recombination events. As a result, we verified the sequences of pig BLM and pig UBL-1/SUMO-1. The nucleic acid and amino acid coding sequence homologies of pig BLM gene with the corresponding human gene were 87.3% and 82.9%, respectively. The nucleic acid and amino acid coding sequence homologies of the pig UBL-1/SUMO-1 gene with the human gene were 96.4% and 100%, respectively. CONCLUSION: Current research into homologous recombination provides the possibility for improvement of gene knockout efficiency by regulating the gene expression profiles of recombination-related genes. Transient interference with the expression of pig UBL-1/SUMO-1 and BLM is expected to improve gene targeting. The results of the present study provided important information to design siRNA knockdown vectors. They were also useful for ex ante evaluation of expression profiles of these genes in primary cultures of somatic cells, which may enhance the production of gene knockout pigs.
Asunto(s)
ADN Helicasas/genética , Proteína SUMO-1/genética , Porcinos/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Síndrome de Bloom/genética , ADN Complementario/química , ADN Complementario/genética , Humanos , Datos de Secuencia Molecular , RecQ Helicasas , Recombinación GenéticaRESUMEN
BACKGROUND: The low rate of homologous recombination in somatic cells is considered to be an urgent issue. Therefore, we molecularly cloned three genes that relate to efficient homologous recombination. METHODS: Polymerase chain reaction (PCR) was performed to isolate candidate cDNA fragments from a pig spleen cDNA library with the corresponding primer sets deduced from multiple alignment analysis of other mammalian genes. A 5'- and 3'-RACE PCR experiment was performed to determine the complete cDNA sequences. RESULTS: The complete cDNA sequences of the pig RAD51, RAD52, and RAD54 genes, which are closely related to homologous recombination events, were identified using molecular cloning technique. The cDNA sequences of three genes were successfully isolated by PCR-based methods. As a result, we determined the sequences of pig RAD51 (1663 bp, 339 aa), RAD52 (1884 bp, 406 aa), and RAD54 (2884 bp, 747 aa). The nucleic acid sequence homologies of the pig RAD51, RAD52, and RAD54 genes compared with the corresponding human genes were 92.9%, 77.3%, and 90.0%; the corresponding amino acid sequence homologies were 98.8%, 71.1%, and 95.0%, respectively. CONCLUSION: The knockout of alpha-1,3-galactosyltransferase in pigs resulted in a drastic reduction in xenoantigenicity. However, other xenoantigens, in particular, the non-Gal antigens, also need to be down-regulated. Gene transfer to alter expression levels of these recombination-related molecules and/or ex ante evaluation of expression profiles of these genes in primary cultures of somatic cells constitute a new approach to enhancing homologous recombination events during the production of gene knockout pigs.
Asunto(s)
Adenosina Trifosfatasas/genética , Recombinasa Rad51/genética , Proteína Recombinante y Reparadora de ADN Rad52/genética , Adenosina Trifosfatasas/química , Secuencia de Aminoácidos , Animales , Animales Modificados Genéticamente , ADN Complementario/química , ADN Complementario/genética , Eliminación de Gen , Datos de Secuencia Molecular , Recombinasa Rad51/química , Proteína Recombinante y Reparadora de ADN Rad52/química , Recombinación Genética , PorcinosRESUMEN
Despite extensive experience with prosthetic replacement for the reconstruction of limbs following juxta-articular resection of tumours, there are few reports of prosthetic replacement of the distal radius. We present two cases of massive bone defects of the distal radius in which alumina ceramic prosthetic replacements were used. We evaluated the patients more than ten years after the procedure. Both patients had degenerative changes to the wrist. This, however, was not associated with pain or decreased function, and both had returned to their previous occupation after surgery. When a patient has a massive defect of the distal radius, reconstruction using a ceramic prosthesis is a reasonable alternative to using autograft. This method of treatment results in little pain, a moderate range of movement and satisfactory function.
Asunto(s)
Neoplasias Óseas/cirugía , Tumor Óseo de Células Gigantes/cirugía , Prótesis e Implantes , Radio (Anatomía)/cirugía , Óxido de Aluminio , Neoplasias Óseas/diagnóstico por imagen , Cerámica , Estudios de Seguimiento , Tumor Óseo de Células Gigantes/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Radiografía , Articulación de la Muñeca/cirugíaRESUMEN
The carcinogenicity of dipyrone (sulpyrin)--[(2,3-dihydro-1,5-dimethyl-3-oxo-2-phenyl-1H-pyrazol-4 -yl) methylamino]methanesulfonic acid sodium salt monohydrate--which is widely used as an antipyretic anodyne in Japan and in some European countries, was examined in 314 (C57BL/6 X C3H)F1 mice. Male animals were given 0.5% (group I-a) or 0.125% (group I-b) dipyrone in their drinking water for 78 weeks, and female animals were given 1.0% (group II-a) or 0.25% (group II-b) dipyrone in their drinking water for 78 weeks; both males and females were observed for 86 weeks. Twenty-seven of 48 (56%) group I-a animals and 36 of 44 (82%) group II-a animals developed hepatic tumors, and the tumors in group II-a mice developed earlier than those in the control animals. The tumor incidences were significantly higher than those of 8 of 44 (18%) and 3 of 51 (6%) in the respective control groups. The multiplicity of the hepatic tumors was also significantly increased in groups I-a, I-b, and II-a. Hepatic adenoma incidence was related to the dose of dipyrone in the males. These results show that dipyrone enhances the development of hepatic tumors in mice.
Asunto(s)
Aminopirina/análogos & derivados , Dipirona/farmacología , Neoplasias Experimentales/inducido químicamente , Animales , Peso Corporal/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Femenino , Hígado/efectos de los fármacos , Neoplasias Hepáticas/inducido químicamente , Neoplasias Hepáticas/epidemiología , Masculino , Ratones , Ratones Endogámicos C3H , Ratones Endogámicos C57BL , Neoplasias Experimentales/epidemiología , Tamaño de los Órganos/efectos de los fármacos , Factores de TiempoRESUMEN
A dialysate of fetal bovine serum stimulated the growth of BHK cells in a medium containing 1% dialyzed serum. The growth-stimulating activity of the dialysate was separated in a single peak with Biogel P-2 chromatography, and a single active component was further fractionated with paper and thin-layer chromatography. The component was identified as biotin. Pure biotin behaved the same as the active component in the dialysate and had the same growth-stimulating activity. The dialysate contained only the free biotin that was present in serum. Free biotin was found in relatively large amounts in fetal (bovine and human) sera, and only a very small percentage of dialysates of adult (bovine, horse, swine, and human) sera had traces of growth-stimulating activity. The possible role of free biotin in the body is discussed.
Asunto(s)
Biotina/farmacología , División Celular/efectos de los fármacos , Medios de Cultivo , Animales , Células Cultivadas , Cricetinae , DiálisisRESUMEN
The carcinogenicity of 1-nitropyrene [(1-NP) CAS: 5522-43-0] and 1,6-dinitropyrene [(1,6-DNP) CAS: 42397-64-8] was examined by their direct injection in a beeswax-tricaprylin vehicle into the lung of male F344/DuCrj rats. Of 28 rats given 0.15 mg of 1,6-DNP, 21 (75%) developed squamous cell carcinomas, 2 (7%) developed undifferentiated carcinomas, and 2 (7%) had squamous metaplasias in the lung by 72 weeks. In 32 rats that received 1.5 mg of 1-NP, neither carcinoma nor squamous metaplasia was induced. In all 19 rats (100%) given 0.5 mg of 3-methylcholanthrene [(MCA) CAS: 56-49-5], squamous cell carcinomas were induced earlier than in rats treated with 1,6-DNP. In 1 of 31 rats (3%) given the beeswax-tricaprylin vehicle only, squamous metaplasia was induced. Distant metastases of induced tumors were observed in 4 rats treated with 1,6-DNP and in 1 rat receiving MCA. Two lung tumors induced by 1,6-DNP were successively transplanted into the same strain of rats for 3 generations.
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Carcinógenos , Carcinoma de Células Escamosas/inducido químicamente , Neoplasias Pulmonares/inducido químicamente , Pirenos/toxicidad , Animales , Carcinoma de Células Escamosas/patología , Neoplasias Renales/secundario , Neoplasias Pulmonares/patología , Masculino , Metilcolantreno , Ratas , Ratas Endogámicas F344RESUMEN
The carcinogenicity of bucetin [(3-hydroxy-p-butyrophenetidide) CAS: 1083-57-4], an antipyretic analgesic drug, was examined in 300 (C57BL/6 X C3H)F1 mice. Groups of 50 mice of each sex were treated with 1.5 or 0.75% bucetin in their basal diet for 76 weeks and then fed a basal diet for 8 weeks. Control groups were given a basal diet for 84 weeks. In 10 of 46 (22%) male mice given the high dose of bucetin and in 6 of 45 (13%) given the low dose, renal cell tumors were induced. Dysplastic lesions of the proximal tubules were frequently seen in the males given bucetin in a dose-related fashion. Neither tumorous nor preneoplastic lesions developed in the kidneys of bucetin-treated female mice and control animals. Papilloma of the urinary bladder in 1 male mouse and papillary or nodular hyperplasia in 9 mice of both sexes were observed in groups given the high dose of bucetin.
Asunto(s)
Aminofenoles/toxicidad , Neoplasias Experimentales/inducido químicamente , Fenetidina/toxicidad , Animales , Peso Corporal/efectos de los fármacos , Carcinoma de Células Renales/inducido químicamente , Relación Dosis-Respuesta a Droga , Femenino , Neoplasias Renales/inducido químicamente , Masculino , Ratones , Ratones Endogámicos C3H , Ratones Endogámicos C57BL , Fenacetina/toxicidad , Fenetidina/análogos & derivados , Neoplasias de la Vejiga Urinaria/inducido químicamenteRESUMEN
1,3-Dinitropyrene (DNP) and 1,8-DNP (CAS: 42397-65-9) are very potent mutagens and induce a frameshift-type mutation in the Salmonella test system. Each compound was tested for tumorigenicity in BALB/c mice by sc inoculation of 0.05 mg of the compound once a week for 20 weeks. Tumors developed at the site of injection of 1,8-DNP in 6 of 15 mice up to 60 weeks after the first injection. The incidence of tumors was statistically significant at a P-value of less than .05 but not of less than .01. Therefore, the carcinogenicity of 1,8-DNP in BALB/c mice was concluded to be weaker than that of benzo[a]pyrene [(BP) CAS: 50-32-8], which induced a 100% tumor incidence when it was injected at the same dose as that of 1,8-DNP. No tumors occurred at the injection site in mice given 1,3-DNP. Most of the tumors induced by 1,8-DNP and BP showed histologic features characteristic of malignant fibrous histiocytoma.
Asunto(s)
Carcinógenos , Pirenos/toxicidad , Animales , Benzo(a)pireno/toxicidad , Histiocitoma Fibroso Benigno/inducido químicamente , Ratones , Ratones Endogámicos BALB C , Neoplasias Experimentales/inducido químicamente , Estadística como AsuntoRESUMEN
In tests on the carcinogenicity of 1,6-dinitropyrene [(1,6-DNP) CAS: 42397-64-8] and 1-nitropyrene [(1-NP) CAS: 5522-43-0], 0.1 mg of each compound was inoculated sc into BALB/c mice once a week for 20 weeks. In the group given injections of 1,6-DNP the first tumor appeared on day 112, and 10 of the 20 mice developed tumors at the injection site by 45 weeks after the first injection. However, no tumors were induced in any of the mice that received injections of 1-NP. All of the induced tumors were transplantable for more than five generations in male BALB/c mice. Most of the tumors showed the characteristic histologic features of malignant fibrous histiocytoma.
Asunto(s)
Carcinógenos , Mutágenos/farmacología , Mutación , Neoplasias Experimentales/patología , Pirenos/farmacología , Animales , Evaluación Preclínica de Medicamentos , Masculino , Ratones , Ratones Endogámicos BALB C , Pruebas de Mutagenicidad , Pirenos/toxicidad , Salmonella typhimurium/efectos de los fármacosRESUMEN
We report a case of leiomyosarcoma of the thoracic spine. Primary leiomyosarcoma is a malignant connective tissue tumor originating from smooth muscle cells. Leiomyosarcoma frequently occurs in the uterus, retroperitoneal space, gastrointestinal tract, and deep soft tissues; primary leiomyosarcoma of the bone is rare. The MR imaging including intravoxel incoherent motion (IVIM) imaging findings of the current case indicated a low diffusion coefficient and high blood flow, which were in concurrence with high cell density on histology and increased vascularity by angiography. Although some benign tumors such as osteoblastoma and giant cell tumor would show similar findings on IVIM imaging, these additional imaging features may narrow the differential diagnosis of spinal tumors.
Asunto(s)
Leiomiosarcoma/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Neoplasias de la Columna Vertebral/diagnóstico por imagen , Vértebras Torácicas/diagnóstico por imagen , Diagnóstico Diferencial , Femenino , Humanos , Leiomiosarcoma/patología , Persona de Mediana Edad , Neoplasias de la Columna Vertebral/patología , Vértebras Torácicas/patologíaRESUMEN
In in vivo experiments, radioactivity from [U-14C]GTP was incorporated into biopterin, and, in fact, all carbon atoms of biopterin synthesized in Ascaris lumbricoides suum originated from GTP. Biopterin was also biosynthesized in homogenates of tissue fluid and muscles of Ascaris lumbricoides suum. The enzyme which catalyzes sepiapterin synthesis from D-erythro-7,8-dihydroneopterin-3'-phosphate was found in A. lumbricoides suum extracts and extracted in the 0--30% (NH4)2SO4 fraction from a 40 000 x g supernatant. The enzyme was purified by Sephadex G-200 column and DEAE-cellulose column chromatography. It is suggested that sepiapterin could be an intermediate compound in biopterin biosynthesis.
Asunto(s)
Ascaris/metabolismo , Biopterinas/biosíntesis , Pteridinas/biosíntesis , Oxidorreductasas de Alcohol/aislamiento & purificación , Animales , Ascaris/enzimología , Líquidos Corporales/metabolismo , Cromatografía DEAE-Celulosa , Cromatografía en Gel , Femenino , Guanosina Trifosfato/metabolismo , Complejos Multienzimáticos/aislamiento & purificación , Músculos/metabolismo , Pterinas/aislamiento & purificación , Pterinas/metabolismoRESUMEN
Kynurenine aminotransferase (L-kynurenine:2-oxoglutarate aminotransferase (cyclizing), EC 2.6.1.7) was purified 378-fold from rat liver mitochondria by digitonin solubilization, heat treatment, DEAE-Sepharose CL-6B chromatography, Sephadex G-100 gel filtration, hydroxyapatite chromatography and chromatofocusing. Elution patterns of alpha-aminoadipate aminotransferase (EC 2.6.1.39) activity were identical with those of kynurenine aminotransferase activity on all column chromatographies. The ratios of the two specific activities were constant throughout the purification. On polyacrylamide gel electrophoresis both activities were detected at the same position. Both enzymatic activities showed the same inactivation curves upon heat inactivation at various temperatures. alpha-Aminoadipate showed competitive inhibiton against kynurenine or 3-hydroxykynurenine. alpha-Ketoadipate was utilized in the kynurenine aminotransferase reaction as an amino acceptor in place of alpha-ketoglutarate. The Km value for alpha-ketoadipate was 10 microM, lower than for alpha-ketoglutarate. These observations indicate that kynurenine aminotransferase is identical with alpha-aminoadipate aminotransferase. The Km values of purified kynurenine aminotransferase were determined at pH 6.5 as: kynurenine, 4.3 mM; pyridoxal 5'-phosphate, 4.2 microM; alpha-ketoglutarate, 20 microM (kynurenine substrate), and 3-hydroxykynurenine, 5.7 mM; pyridoxal 5'-phosphate, 1.7 microM; alpha-ketoglutarate, 13 microM (3-hydroxy-kynurenine substrate). The enzyme was strongly inhibited by Hg2+ and p-chloromercuribenzoate.
Asunto(s)
Liasas , Mitocondrias Hepáticas/enzimología , Transaminasas/metabolismo , 2-Aminoadipato-Transaminasa , Animales , Isoenzimas/aislamiento & purificación , Isoenzimas/metabolismo , Cinética , Masculino , Piruvatos/metabolismo , Ratas , Ratas Endogámicas , Especificidad por Sustrato , Transaminasas/aislamiento & purificaciónRESUMEN
To analyze the boundaries of the functional coding region of the HSV-2(333) thymidine kinase gene (TK gene), deletion mutants of hybrid plasmid pMAR401 H2G, which contains the 17.5 kbp BglII-G fragment of HSV-2 DNA, were prepared and tested for capacity to transform LM(TK-) cells to the thymidine kinase-positive phenotype. These studies showed that hybrid plasmids containing 2.2-2.4 kbp subfragments of HSV-2 BglII-G DNA transformed LM(TK-) cells to the thymidine kinase-positive phenotype and suggested that the region critical for transformation might be less than 2 kbp. That the activity expressed in the transformants was HSV-2 thymidine kinase was shown by experiments with type-specific enzyme-inhibiting rabbit antisera and by disc-polyacrylamide gel electrophoresis analyses. DNA fragments of the HSV-2 TK gene were subcloned in phage M13mp9 and M13mp8. A sequence of 1656 bp containing the entire coding region of the TK gene and the flanking sequences was determined by the dideoxynucleotide chain termination method. Comparisons with the HSV-1(Cl 101) TK gene revealed that PstI, PvuII, and EcoRI cleavage sites had homologous locations as did promoter, translational start and stop, and polyadenylation signals. Extensive homology was observed in the nucleotide sequence preceding the ATG translational start signal and in portions of the coding region of the genes. Comparisons of the predicted amino acid sequences of the HSV-1 and HSV-2 thymidine kinase polypeptides revealed that both were enriched in alanine, arginine, glycine, leucine, and proline residues and that clear, but interrupted homology existed within several regions of the polypeptide chains. Stretches of 15-30 amino acid residues were identical in conserved regions. The possibility is suggested that domains containing some of the conserved amino acid sequences might have a role in substrate binding and as major antigenic determinants.