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1.
Int J Biometeorol ; 62(8): 1497-1506, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29728761

RESUMO

The gradual increase of ambient temperature (TA) at high altitude can cause heat stress as an effect of climate change and may shift the traditional habitat of yak to further higher altitude. Therefore, an attempt has been made in this study to evaluate the thermo-adaptability of yaks to different seasons at high altitude. The adaptive capabilities of yaks were assessed based on different heat tolerance tests in relation to changes in rectal temperature (RT; °F), respiration rate (RR; breaths/min), pulse rate (PR; beats/min), and plasma heat shock protein (HSP) profile. The experiment was conducted in 24 yaks, divided into three groups based on age as calf (n = 8), adult (n = 8), and lactating cow (n = 8). Thermal adaptability was determined by temperature humidity index (THI), dairy search index (DSI), and Benezra's thermal comfort index (BTCI) along with HSP70 profile. The THI was higher (P < 0.01) in summer than winter which increased from lowest (40.87) to highest (61.03) in summer by 20 points, where yaks were under heat load beyond THI 52. The RT (100.09 ± 0.18 °F), RR (21.76 ± 0.18), and PR (59.78 ± 0.32) increased by 23-35%, and this was correlated to the higher values of DSI exceeding 1 in calves (1.35 ± 0.03), lactating cows (1.29 ± 0.04), and adults (1.23 ± 0.32) during summer in comparison to winter (0.98 ± 0.02). The BTCI also showed values greater (P < 0.01) than 2 in calves (3.47 ± 0.27), lactating cows (3.23 ± 0.28), and adults (2.98 ± 0.29) which reflected 49-75% increase in rectal temperature and respiration rate during summer. Further, heat stress was substantiated by threefold higher (P < 0.01) level of plasma HSP70 in calves (189.61 ± 3.90 pg/ml) followed by lactating cows (168.62 ± 3.03 pg/ml) and adults (155.33 ± 2.30 pg/ml) against the winter average of 87.92 ± 3.19 pg/ml. Present results revealed that yaks were experiencing heat stress in summer at an altitude of 3000 m above sea level and calves were more prone to heat stress followed by lactating cows and adults.


Assuntos
Aclimatação , Bovinos/fisiologia , Transtornos de Estresse por Calor/veterinária , Lactação , Animais , Ecossistema , Feminino , Temperatura Alta , Umidade , Temperatura
2.
Asian-Australas J Anim Sci ; 30(2): 246-253, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27221251

RESUMO

OBJECTIVE: Present study explores the effect of hot summer period on the glycolytic rate of early post-mortem meat quality of Ghungroo and Large White Yorkshire (LWY) pig and comparative adaptability to high temperature between above breeds by shifting the expression of stress related genes like mono-carboxylate transporters (MCTs) and heat shock proteins (HSPs). METHODS: Healthy pigs of two different breeds, viz., LYW and Ghungroo (20 from each) were maintained during hot summer period (May to June) with a mean temperature of about 38°C. The pigs were slaughtered and meat samples from the longissimus dorsi (LD) muscles were analyzed for pH, glycogen and lactate content and mRNA expression. Following 24 h of chilling, LD muscle was also taken from the carcasses to evaluate protein solubility and different meat quality measurements. RESULTS: LWY exhibited significantly (p<0.01) higher plasma cortisol and lactate dehydrogenase concentration than Ghungroo indicating their higher sensitivity to high temperature. LD muscle from LWY pigs revealed lower initial and ultimate pH values and higher drip loss compared to Ghungroo, indicating a faster rate of pH fall. LD muscle of Ghungroo had significantly lower lactate content at 45 min postmortem indicating normal postmortem glycolysis and much slower glycolytic rate at early postmortem. LD muscle of LWY showed rapid postmortem glycolysis, higher drip loss and higher degrees of protein denaturation. Ghungroo exhibited slightly better water holding capacity, lower cooking loss and higher protein solubility. All HSPs (HSP27, HSP70, and HSP90) and MCTs (MCT1, MCT2, and MCT4) in the LD muscle of pigs inclined to increase more in Ghungroo than LWY when exposed to high temperature. CONCLUSION: Effect of high temperature on the variation of HSPs and MCTs may play a crucial role in thermal tolerance and adaptation to different climatic conditions, pH regulation, muscle acidification, drip loss, protein denaturation and also in postmortem meat quality development.

3.
Andrologia ; 48(5): 570-5, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26395129

RESUMO

Purified Shilajit, an Ayurvedic rasayana, was evaluated in healthy volunteers of age between 45 and 55 years for its effect on male androgenic hormone viz. testosterone in a randomised, double-blind, placebo-controlled clinical study at a dose of 250 mg twice a day. Treatment with Shilajit for consecutive 90 days revealed that it has significantly (P < 0.05) increased total testosterone, free testosterone and dehydroepiandrosterone (DHEAS) compared with placebo. Gonadotropic hormones (LH and FSH) levels were well maintained.


Assuntos
Minerais/farmacologia , Resinas Vegetais/farmacologia , Testosterona/sangue , Desidroepiandrosterona/sangue , Método Duplo-Cego , Hormônio Foliculoestimulante/sangue , Voluntários Saudáveis , Humanos , Hormônio Luteinizante/sangue , Masculino , Ayurveda , Pessoa de Meia-Idade , Minerais/administração & dosagem , Resinas Vegetais/administração & dosagem
4.
J Assoc Physicians India ; 60: 56-8, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23767205

RESUMO

Andersen-Tawil Syndrome (ATS) is a rare potassium channel disorder, characterized by episodic weakness, ventricular arrhythmias and dysmorphic features (short stature, scoliosis, clinodactyly, hypertelorism, small or prominent low set ears, micrognathia and broad forehead). We report a case of hypokalemic periodic paralysis with dysmorphic facial features and ventricular arrhythmia resembling Andersen-Tawil syndrome.


Assuntos
Síndrome de Andersen/diagnóstico , Arritmias Cardíacas/diagnóstico , Humanos , Paralisia Periódica Hipopotassêmica/diagnóstico , Masculino , Micrognatismo , Retrognatismo , Adulto Jovem
5.
Andrologia ; 42(1): 48-56, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20078516

RESUMO

The safety and spermatogenic activity of processed Shilajit (PS) were evaluated in oligospermic patients. Initially, 60 infertile male patients were assessed and those having total sperm counts below 20 million ml(-1) semen were considered oligospermic and enrolled in the study (n = 35). PS capsule (100 mg) was administered twice daily after major meals for 90 days. Total semenogram and serum testosterone, luteinising hormone and follicle-stimulating hormone were estimated before and at the end of the treatment. Malondialdehyde (MDA), a marker for oxidative stress, content of semen and biochemical parameters for safety were also evaluated. Twenty-eight patients who completed the treatment showed significant (P < 0.001) improvement in spermia (+37.6%), total sperm count (+61.4%), motility (12.4-17.4% after different time intervals), normal sperm count (+18.9%) with concomitant decrease in pus and epithelial cell count compared with baseline value. Significant decrease of semen MDA content (-18.7%) was observed. Moreover, serum testosterone (+23.5%; P < 0.001) and FSH (+9.4%; P < 0.05) levels significantly increased. HPLC chromatogram revealed inclusion of PS constituents in semen. Unaltered hepatic and renal profiles of patients indicated that PS was safe at the given dose. The present findings provide further evidence of the spermatogenic nature of Shilajit, as attributed in Ayurvedic medicine, particularly when administered as PS.


Assuntos
Ayurveda , Oligospermia/tratamento farmacológico , Espermatogênese/efeitos dos fármacos , Adulto , Hormônio Foliculoestimulante/sangue , Humanos , Índia , Hormônio Luteinizante/sangue , Masculino , Estresse Oxidativo/efeitos dos fármacos , Contagem de Espermatozoides , Testosterona/sangue , Resultado do Tratamento
6.
Rev Sci Tech ; 28(3): 1045-50, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20462162

RESUMO

Serum samples were collected from 254 yak (Poephagus grunniens, presently Bos grunniens) in different yak tracts of India. These samples were then screened by virus neutralisation test (VNT) and avidin-biotin enzyme-linked immunosorbent assay (AB-ELISA) to study the seroprevalence of antibodies against bovine herpesvirus type 1 (BHV-1). The overall seroprevalence in yak was found to be 41% (105) by VNT and AB-ELISA. The sex of the animal, whether it was on a farm or free-ranging and the location of the different yak tracts did not seem to have any effect on seroprevalence. However, seroprevalence was found to increase with the age of the animals, being highest in yak older than three years of age (49%). Yak generally share feeding, watering and grazing areas with other domestic and wild animals and this common ecological niche is thought to be a possible avenue of infection. This is the first time that the seroprevalence of antibodies against BHV-1 has been studied in yak in India.


Assuntos
Anticorpos Antivirais/sangue , Herpesvirus Bovino 1/imunologia , Rinotraqueíte Infecciosa Bovina/epidemiologia , Fatores Etários , Animais , Animais Domésticos , Animais Selvagens , Bovinos , Feminino , Índia/epidemiologia , Rinotraqueíte Infecciosa Bovina/transmissão , Masculino , Estudos Soroepidemiológicos
7.
Rev Sci Tech ; 28(3): 1051-5, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20462163

RESUMO

Serum samples were randomly collected from 172 free-ranging yak (Poephagus grunniens, presently Bos grunniens) from six different yak tracts of Arunachal Pradesh, India, and subjected to enzyme-linked immunosorbent assay to detect the presence of specific antibodies against Chlamydophila abortus. The overall prevalence of this disease in yak was 35%. The prevalence of Cp. abortus-specific antibodies was significantly higher in yak cows (41%) than among bulls (25%). The highest prevalence (39%: 95% confidence interval [Cl] = 27, 55) was found in yak between one and three years of age, while the lowest prevalence (20%: 95% CI = 10, 41) was reported in yak below one year of age.


Assuntos
Anticorpos Antibacterianos/sangue , Doenças dos Bovinos/epidemiologia , Infecções por Chlamydia/veterinária , Chlamydia/imunologia , Animais , Animais Selvagens , Bovinos , Infecções por Chlamydia/epidemiologia , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Índia , Masculino , Estudos Soroepidemiológicos , Fatores Sexuais
8.
Anc Sci Life ; 22(4): 146-51, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22557102

RESUMO

Water extract of the leaves of Coleus Aromaticus Benth was tested for its diuretic activity in male albino rats. The study was carried out on normal rats using furosemide as a standard reference drug. Rats were treated with furosemide (4 mg/kg. p.o) and Coleus aromaticus (0.5 g/kg and 1.0 g/kg, p/o). Urine was collected and its volume was recorded. Urinary levels of sodium, potassium and chloride were estimated. Treatment with Coleus aromaticus produced diuresis. The urine output and electrolytes concentration was significantly increased. Hence, it is suggested, Coleus aromaticus leaves has diuretic activity on rats.

9.
Acta Pharmacol Sin ; 22(12): 1113-6, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11749810

RESUMO

AIM: To study wound healing activity of the human placental extract (HPE) in rats. METHODS: Full thickness wounds were inflicted on depilated dorsum of Charles foster rats with 8 mm Acu-punch biopsy. The HPE was applied both at topical and im routes (2.5 mL/kg). Effects were compared on the basis of physical criteria, biochemical criteria, and histopathological study with respect to untreated control, vehicle control (1.5 % benzyl alcohol), and framycetin topical treated groups. RESULTS: Significant lowering of wound size (P<0.05), wound index (P<0.05), and number of days required for complete healing (P<0.01); significant gain in tensile strength (P<0.01); appreciable increase of tissue DNA, total protein, and collagenesis were observed in HPE treated group. CONCLUSION: Human placental extract systematically helps collagenesis leading to potent healing of wounds.


Assuntos
Extratos Placentários/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Colágeno/biossíntese , DNA/biossíntese , DNA/efeitos dos fármacos , Humanos , Extratos Placentários/toxicidade , Ratos
10.
Biochemistry ; 38(40): 13042-54, 1999 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-10529174

RESUMO

Four different mutant alleles of a nuclear gene (MNA6), which lose mt 15S rRNA at nonpermissive temperature (36 degrees C), were previously generated by EMS mutagenesis of Saccharomyces cerevisiae. To understand the biochemical basis for the loss of 15S rRNA in these mutants, the wild-type and mutant alleles of the MNA6 gene were isolated and characterized. The DNA sequencing of the cloned MNA6 gene revealed that it has an open reading frame specifying a 486 amino acid polypeptide, which appears to be a yeast mt homologue of the S4 r-protein family. The large size of this yeast S4 homologue is due to a nonhomologous long C-terminal extension. The MNA6 gene also appeared to be identical to the previously isolated yeast NAM9 gene. The in vitro expression under coupled transcription-translation reaction conditions followed by mt import demonstrated that MNA6 indeed encodes a approximately 56 kDa protein targeted to the mitochondria. We have also demonstrated by Western blot analysis using anti-Mna6p antibody that Mna6p is associated with the small subunit of mitoribosomes. The sequence analysis of the four mutant mna6 alleles revealed that Leu(109) --> Phe, Arg(111) --> Lys, Pro(424) --> Leu, or Pro(438) --> Leu amino acid substitution in Mna6p causes temperature-dependent loss of the 15S rRNA. These mutations do not affect the mitochondrial import or accumulation of Mna6p. Rather the evidence points to an inability of mutant Mna6p to be assembled into the mitoribosomes of cells grown at 36 degrees C.


Assuntos
Substituição de Aminoácidos/genética , Proteínas Fúngicas/genética , Proteínas Nucleares , RNA Ribossômico/metabolismo , RNA/genética , Proteínas Repressoras , Proteínas Ribossômicas/genética , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Alelos , Sequência de Aminoácidos , Anticorpos Antifúngicos/biossíntese , Transporte Biológico , Clonagem Molecular , Proteínas Fúngicas/biossíntese , Proteínas Fúngicas/imunologia , Proteínas Fúngicas/isolamento & purificação , Genes Fúngicos , Dados de Sequência Molecular , RNA/isolamento & purificação , RNA/metabolismo , RNA Mitocondrial , RNA Ribossômico/genética , RNA Ribossômico/isolamento & purificação , Proteínas Ribossômicas/biossíntese , Proteínas Ribossômicas/imunologia , Proteínas Ribossômicas/isolamento & purificação , Proteínas Ribossômicas/metabolismo , Partículas Submitocôndricas/metabolismo , Temperatura
11.
J Ethnopharmacol ; 65(2): 149-56, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10465655

RESUMO

Ayurvedic preparations of metallic iron commonly categorised as different 'putas' of 'Louha Bhasma' was chemically analysed and pharmacologically investigated in iron deficiency anemia. Atomic absorption spectral (AAS) study of different putas of Louha Bhasma revealed the presence of various proportions of important metals along with varied concentration of iron in it. The effect of a representative puta viz. 50 puta of Louha Bhasma in the management of agar gel diet and phlebotomy induced iron deficiency anemia in animal model was found to be statistically highly significant (P < 0.001) in comparison to the control and standard drug Fefol treated groups.


Assuntos
Anemia Ferropriva/tratamento farmacológico , Ferritinas/sangue , Hemoglobinas/análise , Ferro/farmacologia , Extratos Vegetais/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Avaliação de Medicamentos , Ferro/sangue , Ferro/química , Ferro/metabolismo , Masculino , Ayurveda , Plantas Medicinais/química , Ligação Proteica , Ratos , Espectrofotometria Atômica
12.
Biochemistry ; 38(30): 9693-703, 1999 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-10423248

RESUMO

The highly conserved nonanucleotide (5'-TATAAGTAA[+2]) promoter sequence dictates initiation of gene-specific transcription by the mitochondrial (mt) RNA polymerase in yeast mitochondria. However, transcriptional efficiency of the nonanucleotide promoter in different mt genes varies severalfold. To explore the regulatory role of the promoter-proximal template sequence in mt transcription, different deletion, nucleotide (nt) substitution, and tandem promoter constructs were analyzed under in vitro transcription reaction conditions. It has been found that the conserved nonanucleotide promoter plus more than 9 nt of nonconserved sequence 3' to the promoter were absolutely essential for mt gene-specific transcription. In addition, approximately 300 nt of nonspecific DNA sequence 5' to the promoter was also important for efficient transcription. Interestingly, introduction of consecutive T residues in the early transcribed sequence of the template strongly inhibited mt transcription at low nt concentrations (i.e., 5 microM UTP). In contrast, neither other nt clusters nor a bacterial terminator-like sequences at that location inhibited mt transcription. Under the nonproductive reaction conditions, the full-length transcript from the mt polyT template was drastically reduced with the formation of several short abortive oligoribonucleotides. These results suggest that the transcriptional efficacy of the yeast mt promoter is influenced by sequence 3' to the promoter.


Assuntos
Mitocôndrias/genética , Oligodesoxirribonucleotídeos/química , Regiões Promotoras Genéticas , Saccharomyces cerevisiae/genética , Regiões 3' não Traduzidas/química , Sequência de Bases , DNA Fúngico/química , Genoma Fúngico , Mitocôndrias/química , Oligodesoxirribonucleotídeos/genética , Iniciação Traducional da Cadeia Peptídica/genética , Terminação Traducional da Cadeia Peptídica/genética , Poli T/farmacologia , Saccharomyces cerevisiae/química , Sequências de Repetição em Tandem , Transcrição Gênica/efeitos dos fármacos
13.
Gene ; 212(2): 305-14, 1998 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-9611272

RESUMO

Prior work has demonstrated that a conserved nonanucleotide [5'-TATAAGTAA(+2)] promoter sequence is used by the mitochondrial [mt]1 RNA polymerase in Saccharomyces cerevisiae. However, the highly AT-rich yeast mt genome carries many other promoter-like sequences, but only a fraction of them are involved in gene-specific transcription. To examine the sequence variability of this nonanucleotide promoter motif, single or multiple nt substitutions were introduced into the canonical promoter sequence. The transcriptional activity of these altered promoter sequences was examined under the in-vitro reaction conditions. The results presented here determined that several variant promoter sequences (i. e. TAAAAGTAA, TATAAGAAA, TATAAGTAG, TATAAGAAG, TATAAGAGA, TATAAGGGA, TATAAGTGG, TAAAAGTAG) were efficiently used by the mtRNA polymerase. However, a single (i.e. AATAAGTAA, TTTAAGTAA, TATTAGTAA, TATAACTAA, TATAAGGAA, TATAAGTAT) or multiple (TATAGGAAA, TAAAAGGAA, TATAGGGAA, TAAAGGAAA, TAAAGGGAA) nt substitution(s) in other locations drastically reduced mt promoter function. Interestingly, some of these poorly or partially active promoter variants (i.e. TATAAGGAA, TATAAGTAT, TATAAGTCA) became fully functional in the presence of sequence-specific dinucleotide primer. Since dinucleotide primer bypasses the first phosphodiester bond formation in transcription, it is suggested that the -1T-->G, +1A-->C and +2A-->T mutations affect mt transcription at the level of initiation rather than polymerase binding.


Assuntos
DNA Fúngico/genética , DNA Mitocondrial/genética , RNA Polimerases Dirigidas por DNA/genética , Mitocôndrias/enzimologia , Mitocôndrias/genética , Regiões Promotoras Genéticas , Saccharomyces cerevisiae/genética , DNA Fúngico/metabolismo , Mutagênese Sítio-Dirigida , Oligorribonucleotídeos/genética , Moldes Genéticos , Transcrição Gênica
14.
J Mol Biol ; 275(4): 547-60, 1998 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-9466930

RESUMO

The 3' flanking nucleotide(s) of the octanucleotide promoter sequence regulates transcriptional efficiency of some mitochondrial genes in Saccharomyces cerevisiae. To understand this regulation the in vitro transcriptional activity of various synthetic mitochondrial promoters carrying different 3' flanking sequences was examined. The results presented here demonstrate that consecutive thymidine residues, but no other polynucleotides or secondary structure, in the promoter-proximal non-transcribed DNA strand inhibited mitochondrial transcription. The location and the number of T residues in the cluster as well as the concentration of UTP in the transcription reaction are the important factors determining this transcriptional inhibition. For example, a pair of thymidine nucleotides at positions +2 and +3 is sufficient for inactivation of mitochondrial transcription, whereas more than three consecutive thymidine nucleotides beyond these positions are required for inhibition of mitochondrial transcription. However, a cluster of six to 12 thymidine residues beyond position +11, a point where mtRNA polymerase has been shown to form a stable transcription complex, did not interfere with mitochondrial transcription. Interestingly, at low UTP concentration the mtRNA polymerase generates a large quantity of aborted initiation products on a template carrying promoter-proximal poly(T) sequence probably due to the inability of the polymerase to clear this promoter. On the other hand at high UTP concentration the same mtRNA polymerase on the same mitochondrial promoter produces a higher level of productive initiation complex. These observations suggest that the mechanism of poly(T) inhibition of mitochondrial transcription is a UTP-limited transcriptional attenuation at the promoter site, which might occur under specific physiological conditions (i.e. glucose repression-derepression, switching of aerobic-anaerobic conditions).


Assuntos
Mitocôndrias/genética , Mitocôndrias/metabolismo , Inibidores da Síntese de Ácido Nucleico/farmacologia , Poli T/farmacologia , Regiões Promotoras Genéticas/genética , Saccharomyces cerevisiae/genética , Transcrição Gênica , Modelos Biológicos , Conformação de Ácido Nucleico/efeitos dos fármacos , Oligonucleotídeos/genética , Iniciação Traducional da Cadeia Peptídica/genética , Saccharomyces cerevisiae/fisiologia , Nucleotídeos de Timina/farmacologia , Transcrição Gênica/efeitos dos fármacos
15.
Arch Biochem Biophys ; 340(2): 250-6, 1997 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-9143328

RESUMO

The mitochondrial RNase P RNA gene in yeast Saccharomyces cerevisiae is transcribed from a variant mitochondrial promoter (SP). The sequence of this SP promoter [TATAAGAAG (+2)] differs from the conserved mitochondrial promoter sequence [TATAAGTAA (+2)] by-1T-->A and +2A-->G nucleotide substitutions. To determine the effect of these nucleotide alterations in mitochondrial promoter function, an in vitro transcription analysis was carried out. In the presence of high concentrations of rNTPs (i.e., 125 microM), transcription initiation on the wild-type or variant promoter occurred at the conventional 3' adenine nucleotide. However, at low rNTP concentrations (i.e., 5 microM) and in the presence of a complementary dinucleotide primer corresponding to positions -1 + 1, the mitochondrial RNA polymerase started transcription one nucleotide upstream of the conventional start site. Surprisingly, in the presence of some noncomplementary dinucleotides (i.e., GpA or CpA), which do not have perfect Watson-Crick base pairing with the initiator sequence, transcriptional initiation also occurred with the SP promoter but not with the conserved promoter sequence. This finding is the first example of utilization of noncomplementary dinucleotide primer by an RNA polymerase. Further analysis of mitochondrial promoter function by site-directed mutagenesis determined that the guanine nucleotide at position +2 is mainly responsible for this unusual function of the SP promoter.


Assuntos
RNA Polimerases Dirigidas por DNA/metabolismo , Endorribonucleases/genética , Mitocôndrias/enzimologia , RNA Catalítico/genética , Transcrição Gênica , Regiões Promotoras Genéticas , RNA Fúngico/biossíntese , RNA Fúngico/genética , Ribonuclease P , Saccharomyces cerevisiae/enzimologia , Especificidade por Substrato
16.
Gene ; 170(1): 23-30, 1996 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-8621084

RESUMO

Ribonuclease P (RNase P) is a common tRNA processing enzyme that removes the 5' leader sequence of precursor tRNAs. This activity is identified in yeast mitochondria as a separate enzyme from the nuclear RNase P. Like other RNase P enzymes, the mitochondrial (mt) RNase P is also a ribonucleoprotein composed of both RNA and protein subunits. The RNA subunit is encoded by a mt gene and the protein subunit is supplied by a nuclear gene. Earlier studies described one active promoter (FP1) located 5' to the mt tRNA(fMet)-RNase P RNA-tRNA(Pro) gene cluster, so that the mitochondrially encoded RNA subunit was thought to be co-transcribed with two of its substrate tRNAs. However, the results of in vitro transcription and primer extension experiments presented here demonstrate that the mt RNase P RNA subunit-encoding gene (RPM1) is transcribed from a new promoter (SP)which is located between the tRNA(fMet) and RPM1 genes. The sequence [5'-TATAAGAA(+1)] of the new promoter varies from the conserved promoter sequence [5'-TATAAGTA(+1)], but is one of the sequences that is active in the in vitro transcription assay to determine the consensus promoter sequence [5'-T A T/a A A/g/c G T/a/c N(+1)]. This result demonstrates that a naturally occurring variant promoter is used by RPM1. Identification of the novel SP promoter suggests that the synthesis of the mt RNase P RNA subunit might be uncoupled from the expression of upstream tRNA(fMet) gene, and that RPM1 might be independently transcribed in Saccharomyces cerevisiae.


Assuntos
DNA Fúngico/genética , DNA Mitocondrial/genética , Endorribonucleases/genética , Proteínas Fúngicas/genética , Regiões Promotoras Genéticas , RNA Catalítico/genética , RNA Fúngico/genética , Saccharomyces cerevisiae/genética , Animais , Sequência de Bases , Cricetinae , Endorribonucleases/química , Proteínas Fúngicas/química , Regulação Fúngica da Expressão Gênica , Genes Fúngicos , Mitocôndrias/enzimologia , Dados de Sequência Molecular , RNA Catalítico/química , Ribonuclease P , Saccharomyces cerevisiae/enzimologia , Transcrição Gênica
17.
Phytochemistry ; 41(6): 1457-8, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8722085

RESUMO

Acid phosphatase I (AP-I) is the major isoform of Vigna acid phosphatase. It is constitutively expressed in seed cotyledons during germination. AP-I was separated from other isoforms and purified to homogeneity by three simple purification steps; (NH4)2SO4 precipitation, and phosphocellulose and DEAE-cellulose column chromatography. The activity of AP-I was not affected by 1 mM Mg2+, Mn2+, Ca2+, Co2+ or Pb2+, but severely inhibited by 1 mM Cu2+, Fe3+, Hg2+, Mo6+ or Zn2+. AP-I has both phosphatase and pyrophosphatase activities, and is highly stable even at 50 degrees.


Assuntos
Fosfatase Ácida/isolamento & purificação , Fosfatase Ácida/metabolismo , Fabaceae/enzimologia , Isoenzimas/isolamento & purificação , Isoenzimas/metabolismo , Plantas Medicinais , Sulfato de Amônio , Cátions/farmacologia , Cromatografia DEAE-Celulose , Cromatografia por Troca Iônica , Cinética , Sementes
19.
Acta Biochim Pol ; 42(3): 317-24, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8588482

RESUMO

Mitochondrial DNA polymerase from Saccharomyces cerevisiae, purified 3500 fold, was separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis into three polypeptides. The major 150 kDa polypeptide was probably the catalytic subunit of the mitochondrial (mt) DNA polymerase and the other two polypeptides could be either proteolytic cleavage products of the polymerase, other subunits of the enzyme or protein contaminants. The mtDNA polymerase preferred an A+T-rich DNA template and did not require any RNA primer for DNA synthesis, at least under in vitro reaction conditions. It showed higher processivity on a double-stranded linear DNA template than on a single-stranded circular DNA template, and was capable of synthesizing at least about 1200 nucleotide primer-extended products without any major pause on a double-stranded DNA template.


Assuntos
DNA Fúngico/biossíntese , DNA Mitocondrial/biossíntese , DNA Polimerase Dirigida por DNA/metabolismo , Mitocôndrias/metabolismo , Saccharomyces cerevisiae/metabolismo , Sequência de Bases , DNA Fúngico/genética , DNA Mitocondrial/genética , DNA Polimerase Dirigida por DNA/química , DNA Polimerase Dirigida por DNA/isolamento & purificação , Estabilidade Enzimática , Etilmaleimida/farmacologia , Cinética , Metais/farmacologia , Dados de Sequência Molecular , Estrutura Molecular , Saccharomyces cerevisiae/genética , Especificidade por Substrato
20.
Artigo em Inglês | MEDLINE | ID: mdl-20952958

RESUMO

X-rays of the cervical spines from patients with psoriasis and psoriatic arthritis were compared with similar films from a control population. Apophyseal narrowing, sclerosis, and calcification of anterior ligamants were found more commonly in patients than in controls.

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