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1.
Cytotechnology ; 74(2): 341-349, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35464159

RESUMO

Perilla frutescens (L.) Britton var. frutescens (egoma in Japan) is a traditional oilseed that has several varieties with different photoperiod responses. Although egoma pomace, industrial waste produced during oil extraction, is a rich source of macro- and micro-nutrients such as protein, fiber, minerals, and polyphenols, it has not yet been used for purposes other than livestock feeding. To find out a better use of perilla pomace and its function, we selected four varieties of egoma originating from different regions with different photoperiod responses: two varieties were from Japan, which are broadly cultivated for oilseed and are highly sensitive to light and temperature. The other two varieties from Nepal, which are tolerant to low light and low temperature. Rosmarinic acid-3-O-glucoside, rosmarinic acid, and apigenin-7-O-glucoside were detected as the main polyphenolic constituents in every variety, while apigenin and luteolin were present only in perilla pomace from Japan. In IgE-sensitized RBL-2H3 cells, polyphenols derived from two varieties of Japan suppressed degranulation of mast cells, but those derived from the two varieties of Nepal did not, indicating that apigenin and luteolin may be in part responsible for the anti-allergic response. In addition, it was found that proteins involved in the degranulation signaling pathway, such as PLCγ2, Syk, and Akt, were less phosphorylated in cells treated with the egoma pomace extracts of Japanese origin. Taken together, pomace from egoma varieties derived from different regions may differently modulate allergic response in part due to the difference in polyphenol composition and may be applied to develop nutraceuticals and functional foods fortified with anti-allergic properties.

2.
Cytotechnology ; 74(2): 309-317, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35464168

RESUMO

Lotus root is a traditional food ingredient used primarily in Asia and is rich in polyphenols. To determine its potential use in antiphotoaging, polyphenols were extracted from lotus root with 50% ethanol, and the activity of matrix metalloproteinase (MMP) was measured in dermal cells treated with ultraviolet A (UVA). UVA exposure increased the gene expression of IL-1α, the mRNA levels of MMP-1, and hence, the levels of MMP-1 protein in HaCaT cells, whereas cells treated with lotus polyphenol (LP) normalized these values to the control. In the presence of LP at concentrations of 1 and 10 µg/mL, both the secretion of IL-1α and protein levels of MMP-1 in human keratinocyte cells significantly reduced. Similarly, in the LabCyte EPI-MODEL24, irradiation with UVA caused an increase in mRNA expression of IL-1α and MMP-1, which was prevented by adding LP to the cells. Our results with three different skin cells accordingly showed that LP may help maintain skin health through decreased levels of MMP-1 activity via its anti-inflammatory properties.

3.
Cytotechnology ; 73(3): 333-342, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34149169

RESUMO

We found that strawberry extract suppressed immunoglobulin (Ig) E production in vitro and in vivo, and identified glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as one of the IgE suppressor in the extract. We report here the effect of GAPDH on various Ig productions in vitro and in vivo. GAPDH suppressed IgE and enhanced IgA, IgG and IgM productions in ovalbumin (OVA)-stimulated human peripheral blood mononuclear cells. Oral administration of GAPDH at 10 mg/kg/day to OVA-induced allergy model mice tended to decrease total IgE level and increase total IgA and IgG levels in sera, and also decreased OVA-specific IgE and IgG levels. It is known that the increase of total IgA as well as the decrease of total and specific IgE is important for alleviating allergic symptoms. In addition, GAPDH accelerated IgA production and increased some cytokine secretions such as IL-4, TGF-ß1 and IFN-γ in the OVA-immunized mice spleen lymphocytes. These cytokines involved in the class-switching, IgA enhancement, and IgE suppression, respectively, supporting above results. Our study suggests a possibility that oral administration of GAPDH may induce the immunomodulation in allergic responses.

4.
J Agric Food Chem ; 68(51): 15199-15207, 2020 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-33306387

RESUMO

Asparagus (Asparagus officinalis L.) is one of the widely consumed vegetables. To investigate the mechanism underlying the anti-allergic responses of asparagus, we extracted different fractions from asparagus and measured their inhibitory effects on ß-hexosaminidase release in RBL-2H3 cells in vitro and an atopic dermatitis NC/Nga mouse model in vivo. The lipid fractions from asparagus were extracted with 50% ethanol, separated using chloroform by liquid-liquid phase separation, and fractionated by solid-phase extraction. Among them, acetone fraction (rich in glycolipid) and MeOH fraction (rich in phospholipid) markedly inhibited ß-hexosaminidase release from RBL-2H3 cells. In NC/Nga mice treated with picryl chloride, atopic dermatitis was alleviated following exposure to the 50% EtOH extract, acetone fraction, and methanol fraction. The inhibitory effects of asparagus fractions in vivo were supported by the significant decrease in serum immunoglobulin E (IgE) levels. The phospholipid fractions showed significantly better inhibitory effects, and phosphatidic acid from this fraction showed the best inhibitory effect on ß-hexosaminidase release. In mice challenged with ovalbumin (OVA), oral administration of asparagus extract and its fractions decreased the OVA-specific IgE level and total IgE, indicating that these effects may be partly mediated through the downregulation of antigen-specific IgE production. Taken together, the present study shows for the first time that asparagus extract and its lipid fractions could potentially mitigate allergic reactions by decreasing degranulation in granulocytes. Our study provides useful information to develop nutraceuticals and functional foods fortified with asparagus.


Assuntos
Antialérgicos/administração & dosagem , Asparagus/química , Dermatite Atópica/tratamento farmacológico , Dermatite Atópica/imunologia , Fosfolipídeos/administração & dosagem , Extratos Vegetais/administração & dosagem , Animais , Antialérgicos/química , Antialérgicos/isolamento & purificação , Feminino , Granulócitos/efeitos dos fármacos , Granulócitos/imunologia , Hexosaminidases/imunologia , Humanos , Imunoglobulina E/imunologia , Camundongos Endogâmicos BALB C , Fosfolipídeos/química , Fosfolipídeos/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação
5.
J Chem Phys ; 153(8): 084307, 2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32872873

RESUMO

Coherent wavepacket oscillation accompanying the ultrafast photoexcited intramolecular charge separation (CS) of 9,9'-bianthryl (BA) and 10-cyano-9,9'-bianthryl (CBA) in a room temperature ionic liquid, N,N-diethyl-N-methyl-N-(methoxyethyl)ammonium tetrafluoroborate (DemeBF4), was investigated by femtosecond time-resolved transient absorption spectroscopy. The frequency of the coherent oscillation observed for CBA in nonpolar n-hexane solution (Hex) was 377 cm-1, while this oscillation was undetectable in DemeBF4. For BA in DemeBF4, coherent oscillation with a frequency of 394 cm-1 was observed, which is similar to that for CBA in Hex. CS of CBA occurs in the ultrashort time range of ≤100 fs, while that of BA occurs in a few picosecond range [E. Takeuchi et al., J. Phys. Chem. C 120, 14502-14512 (2016)]. Hence, the oscillation of CBA in Hex and that of BA in DemeBF4 are assigned to the molecular vibration in the locally excited state, while this oscillation dephases instantaneously for CBA in DemeBF4 due to the ultrafast CS and no oscillation was generated in the CS state. This result suggests that the CS reaction is not mediated by a specific intramolecular vibration in the CS state but occurs incoherently through higher levels of multiple vibrational modes.

6.
Cytotechnology ; 71(2): 573-581, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30771057

RESUMO

We found that strawberry (Fragaria x ananassa) extract has an IgE production suppressive activity and its oral administration improved skin manifestation in atopic dermatitis model mice. In present study, we identified an active substance using the IgE-producing human myeloma cell line U266. Gel filtration experiment indicated that the IgE suppressor was more than 6 kDa in molecular size. In addition, its pectinase treatment inhibited the activity, suggesting that the active substance in strawberry extract is pectin. Among solutions of water-(WP), hexametaphosphate-(HXP), acid-(HP) and alkali soluble pectin (OHP) extracted from strawberry, only OHP suppressed IgE production, and their suppressive activity was cancelled by pectinase treatment. In addition, OHP extracted from apple also inhibited IgE production. Furthermore, OHP also suppressed IgE production and did not affect IgG and IgM production in human peripheral blood mononuclear cells in an in vitro immunization condition. From these results, we concluded that OHP was an IgE suppressor in strawberry extract.

7.
Gut Pathog ; 9: 21, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28439300

RESUMO

BACKGROUND: Helicobacter pylori infection is associated with risk for chronic gastritis (CG), gastric ulcer (GU), duodenal ulcer (DU), and gastric cancer (GC). The H. pylori Cag type IV secretion system (TFSS) translocates the virulence factor cytotoxin-associated gene A protein into host cells and plays an important role in initiating gastric carcinogenesis. The CagL and CagI proteins are components of the TFSS. The Arg-Gly-Asp (RGD) motif of CagL, and the six most distal C-terminal amino acids (Ser-Lys-Ile-Ile-Val-Lys, and Ser-Lys-Val-Ile-Val-Lys) of CagL and CagI are essential for TFSS adhesion to host cells. Additionally, the CagL variant Tyr58Glu59 was previously shown to be associated with GC patients. RESULTS: We isolated 43 H. pylori isolates from 17 CG, 8 GU, 8 DU, and 10 GC patients in Southeast Asia. Total DNAs were extracted and sequenced with MiSeq. H. pylori strain ATCC 26695, which was isolated from CG patients, was used as a reference. We examined the full sequences of H. pylori cagL and cagI using whole-genome sequencing (WGS), and analyzed whether single nucleotide variants and amino acid changes (AACs) correlated with adverse clinical outcomes. Three isolates were excluded from the analysis due to cagPAI rearrangements. CagL RGD motifs were conserved in 39 isolates (97.5%). CagL-Glu59 and Ile234 in the C-terminal motif were more common in 10 H. pylori isolates from GC patients (p < 0.001 and p < 0.05, respectively). When 5 Vietnamese isolates from GC patients were excluded, CagL-Glu59 still remains significant (p < 0.05), but not Ile234. CagL-Tyr58 was seen in only one isolate. The CagI C-terminal motif was completely conserved across all 40 isolates, and there were no significant AACs in CagI. CONCLUSIONS: Using WGS, we analyzed genetic variants in clinical H. pylori isolates and identified putative novel and candidate variants in uncharacterized CagL and CagI sequences that are related to gastric carcinogenesis. In particular, CagL-Glu59 has the possible association with GC.

8.
Gut Pathog ; 6: 27, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24995043

RESUMO

BACKGROUND: Clarithromycin (CLR) is the key drug in eradication therapy of Helicobacter pylori (H. pylori) infection, and widespread use of CLR has led to an increase in primary CLR-resistant H. pylori. The known mechanism of CLR resistance has been established in A2146G and A2147G mutations in the 23S rRNA gene, but evidence of the involvement of other genetic mechanisms is lacking. Using the MiSeq platform, whole-genome sequencing of the 19 clinical strains and the reference strain ATCC26695 was performed to identify single nucleotide variants (SNVs) of multi-drug resistant efflux pump genes in the CLR-resistant phenotype. RESULTS: Based on sequencing data of ATCC26695, over one million sequencing reads with over 50-fold coverage were sufficient to detect SNVs, but not indels in the bacterial genome. Sequencing reads of the clinical isolates ranged from 1.82 to 10.8 million, and average coverage ranged from 90.9- to 686.3-fold, which were acceptable criteria for detecting SNVs. Utilizing the conventional approach of allele-specific PCR, point mutations in the 23S rRNA gene were detected in 12 clinical resistant isolates, but not in 7 clinical susceptible isolates. All sequencing reads of CLR-resistant strains had a G mutation in an identical position of the 23S rRNA gene. In addition, genetic variants of four gene clusters (hp0605-hp0607, hp0971-hp0969, hp1327-hp1329, and hp1489-hp1487) of TolC homologues, which have been implicated in multi-drug resistance, were examined. Specific SNVs were dominantly found in resistant strains. CONCLUSIONS: Gene clusters of TolC homologues are involved in CLR susceptibility profiles in individual H. pylori strains. Whole-genome sequencing has yielded novel understanding of genotype-phenotype relationships.

9.
Molecules ; 19(6): 8238-60, 2014 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-24945578

RESUMO

Besides being a useful building material, bamboo also is a potential source of bioactive substances. Although some studies have been performed to examine its use in terms of the biological activity, only certain parts of bamboo, especially the leaves or shoots, have been studied. Comprehensive and comparative studies among different parts of bamboo would contribute to a better understanding and application of this knowledge. In this study, the biological activities of ethanol and water extracts from the leaves, branches, outer culm, inner culm, knots, rhizomes and roots of Phyllostachys pubescens, the major species of bamboo in Japan, were comparatively evaluated. The phytochemical profiles of these extracts were tentatively determined by liquid chromatography-mass spectrometry (LC-MS) analysis. The results showed that extracts from different parts of bamboo had different chemical compositions and different antioxidative, antibacterial and antiallergic activities, as well as on on melanin biosynthesis. Outer culm and inner culm were found to be the most important sources of active compounds. 8-C-Glucosylapigenin, luteolin derivatives and chlorogenic acid were the most probable compounds responsible for the anti-allergy activity of these bamboo extracts. Our study suggests the potential use of bamboo as a functional ingredient in cosmetics or other health-related products.


Assuntos
Bambusa/química , Extratos Vegetais/química , Folhas de Planta/química , Antialérgicos/química , Antibacterianos/química , Ácido Clorogênico/química , Cromatografia Líquida , Luteolina/química , Espectrometria de Massas
10.
Antimicrob Agents Chemother ; 58(9): 5024-35, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24841271

RESUMO

Heterogeneous vancomycin-intermediate Staphylococcus aureus (hVISA) clinical strain Mu3 spontaneously generates VISA strains at an extremely high frequency (≥1×10(-6)). The generated VISA strains usually grow more slowly than does the parent hVISA strain, but they form colonies on vancomycin-containing agar plates before 48 h of incubation. However, we noticed a curious group of VISA strains, designated "slow VISA" (sVISA), whose colonies appear only after 72 h of incubation. They have extremely prolonged doubling times but have vancomycin MICs of 8 to ∼24 mg/liter when determined after 72 to ∼144 h of incubation. We established strain Mu3-6R-P (6R-P), which has a vancomycin MIC of 16 mg/liter (at 72 h), as a representative sVISA strain. Its cell wall was thickened and autolytic activity was decreased compared to the respective qualities of the parent hVISA strain Mu3. Whole-genome sequencing of 6R-P revealed only one mutation, encoded by rpoB (R512P), which replaced the 512th arginine of the RNA polymerase ß-subunit with proline. Its VISA phenotype was unstable, and the strain frequently reverted to hVISA with concomitant losses of pinpoint colony morphology and cell wall thickness and reduced autolytic activity. Sequencing of the rpoB genes of the phenotypic revertant strains revealed mutations affecting the 512th codon, where the proline of 6R-P was replaced with leucine, serine, or histidine. Slow VISA generated in the tissues of an infected patient serves as a temporary shelter for hVISA to survive vancomycin therapy. The sVISA strain spontaneously returns to hVISA when the threat of vancomycin is lifted. The rpoB(R512P) mutation may be regarded as a regulatory mutation that switches the reversible phenotype of sVISA on and off.


Assuntos
Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/genética , Resistência a Vancomicina/genética , Vancomicina/farmacologia , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Parede Celular/efeitos dos fármacos , Parede Celular/genética , Parede Celular/microbiologia , RNA Polimerases Dirigidas por DNA/genética , Genoma Bacteriano/genética , Testes de Sensibilidade Microbiana/métodos , Mutação/genética , Fenótipo
11.
J Glob Antimicrob Resist ; 2(4): 213-224, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27873679

RESUMO

Vancomycin-intermediate Staphylococcus aureus (VISA) and its precursor hetero-VISA (hVISA) were discovered almost 20 years ago and have continued to be a stumbling block in the chemotherapy of methicillin-resistant S. aureus (MRSA). Unlike vancomycin resistance mediated by the van gene in enterococci and staphylococci, VISA is generated by accumulation of mutations. It displays diverse and intriguing genetic mechanisms underlying its resistance phenotype. Here we make a brief note on our recent understanding of the genetics of hVISA, VISA and the newly discovered phenotype 'slow VISA' (sVISA).

12.
J Infect Chemother ; 19(5): 871-5, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23558667

RESUMO

Hospital-wide active surveillance for methicillin-resistant Staphylococcus aureus (MRSA) targeted to adult patients with a history of MRSA carriage within the past 5 years was performed in Juntendo University Hospital (JUH) over a 2-year period. In the first year, MRSA screening culture was ordered by physicians in charge. In the second year, infection-control practitioners (ICPs) took samples for active surveillance culture. The average monthly transmission rate of MRSA in JUH was 0.35 per 1,000 bed-days in the first year and decreased significantly to 0.26 per 1,000 bed-days in the second year (P < 0.05). In the second year, more active commitment of ICPs to MRSA screening was effective in improving the performance rate of screening, shortening turn-around time of screening results, and decreasing transmission rate. Increasing compliance with active MRSA surveillance by involvement of ICPs, targeting patients with a previous history of MRSA carriage in the previous 5 years, was effective to control nosocomial MRSA transmission.


Assuntos
Infecção Hospitalar/epidemiologia , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Vigilância em Saúde Pública/métodos , Infecções Estafilocócicas/epidemiologia , Portador Sadio/epidemiologia , Infecção Hospitalar/prevenção & controle , Infecção Hospitalar/transmissão , Hospitais Universitários/estatística & dados numéricos , Humanos , Japão/epidemiologia , Infecções Estafilocócicas/prevenção & controle , Infecções Estafilocócicas/transmissão
13.
Proc Natl Acad Sci U S A ; 109(25): E1647-56, 2012 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-22645353

RESUMO

Genome inversions are ubiquitous in organisms ranging from prokaryotes to eukaryotes. Typical examples can be identified by comparing the genomes of two or more closely related organisms, where genome inversion footprints are clearly visible. Although the evolutionary implications of this phenomenon are huge, little is known about the function and biological meaning of this process. Here, we report our findings on a bacterium that generates a reversible, large-scale inversion of its chromosome (about half of its total genome) at high frequencies of up to once every four generations. This inversion switches on or off bacterial phenotypes, including colony morphology, antibiotic susceptibility, hemolytic activity, and expression of dozens of genes. Quantitative measurements and mathematical analyses indicate that this reversible switching is stochastic but self-organized so as to maintain two forms of stable cell populations (i.e., small colony variant, normal colony variant) as a bet-hedging strategy. Thus, this heritable and reversible genome fluctuation seems to govern the bacterial life cycle; it has a profound impact on the course and outcomes of bacterial infections.


Assuntos
Bactérias/genética , Cromossomos Bacterianos , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Southern Blotting , Inversão Cromossômica , Eletroforese em Gel de Campo Pulsado , Testes de Sensibilidade Microbiana , Análise de Sequência com Séries de Oligonucleotídeos , Processos Estocásticos
14.
J Mol Microbiol Biotechnol ; 22(1): 17-23, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22353788

RESUMO

The Escherichia coli yqgF gene is highly conserved across a broad spectrum of bacterial genomes. The gene was first identified as being essential for cell growth during screening for targets for broad-spectrum antibiotics. YqgF is structurally similar to RuvC, a Holliday junction resolvase, but its function has not been established. This study describes the isolation of a temperature-sensitive yqgF mutant, the growth of which was inhibited by rho or nusA multicopy plasmids, indicating that YqgF is involved in transcription. Rho is a global transcription termination factor that acts at Rho-dependent terminator sites, which exist not only at the ends of genes but also within genes. The transcription of genes possessing intragenic, or upstream, Rho-dependent terminators was reduced in temperature-sensitive yqgF mutants. This transcription inhibition was sensitive to the Rho inhibitor, bicyclomycin. In addition, the transcription of mutant tnaA genes defective for upstream Rho-dependent termination was not significantly affected by the yqgF mutation. Taken together, these results suggest that YqgF is involved in anti-termination at Rho-dependent terminators in vivo.


Assuntos
Endodesoxirribonucleases/genética , Endodesoxirribonucleases/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Mutação , Transcrição Gênica , Escherichia coli/genética , Genes Essenciais , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Fator Rho/metabolismo , Regiões Terminadoras Genéticas
15.
Cytotechnology ; 64(3): 309-14, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22328134

RESUMO

We purified and identified an IgE suppressor from the strawberry 'Toyonoka', based on the decrease of IgE production in in vitro immunization (IVI). Gel filtration experiment indicated that fractions in a 15-48 kDa range and <10 kDa have an IgE suppressive activity. Furthermore, the fraction in 15-48 kDa was subjected to chromatofocusing and found to have activities at isoelectric points, pI 6.0, 7.0, and 8.0-9.2. We focused on the active fractions of pI 8.0-9.2 and the purified a large amount of strawberry extracts by cation exchange resins in batch. A purified 39 kDa protein showed homology to plant glyceraldehyde-3-phosphate dehydrogenase (GAPDH) in N-terminal amino acid sequence and had GAPDH enzymatic activity. Nucleotide sequence and deduced amino acid sequence of the obtained cDNA clone of the protein matched with the sequence of Fragaria x ananassa GAPDH in the GenBank with >98% identical nucleotides and >99% identical amino acids, respectively. The purified strawberry GAPDH suppressed total IgE production in IVI in a dose-dependent manner. From these results, we identified GAPDH as IgE suppressor in the strawberry. Our study may be applicable to the development of new methods to relieve allergic conditions using GAPDH and the screening of other functional factors for human health.

16.
Phys Rev Lett ; 103(20): 202701, 2009 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-20365981

RESUMO

We propose a novel extension of the standard coupled-channels framework for heavy-ion reactions in order to analyze fusion reactions at deep-sub-barrier incident energies. This extension simulates a smooth transition between the two-body and the adiabatic one-body states. To this end, we damp gradually the off-diagonal part of the coupling potential, for which the position of the onset of the damping varies for each eigenchannel. We show that this model accounts well for the steep falloff of the fusion cross sections for the (16)O + (208)Pb, (64)Ni + (64)Ni, and (58)Ni + (58)Ni reactions.

17.
Mol Microbiol ; 70(6): 1570-8, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19019153

RESUMO

Escherichia coli ribonuclease LS was first characterized as a potential antagonist of bacteriophage T4; the E. coli rnlA gene is required for this activity. When rnlA mutant cells were grown on Luria-Bertani agar containing a high concentration of NaCl, their growth was substantially impaired, and introduction of a mutation into crp or cyaA alleviated the NaCl sensitivity. A mutation in rnlA caused fivefold overexpression of Crp. At the same time, the expression of sigma(38) was lower by two- to threefold in an rnlA mutant than in the wild type, which probably accounts for the susceptibility to high NaCl concentration. The overproduction of Crp was eliminated by deletion of the Crp-site II, to which Crp binds to enhance its own transcription in the presence of abnormally high concentration of cAMP. Consistently, introduction of a mutation into cyaA also eliminated the overproduction of Crp. In fact, all of CyaA, cAMP and cyaA transcripts accumulated to high levels and, after induction, cyaA transcripts were markedly stabilized in an rnlA mutant compared with the wild type. We conclude that RNase LS regulates Crp-cAMP concentration by degrading the cyaA transcripts.


Assuntos
Adenilil Ciclases/metabolismo , Proteína Receptora de AMP Cíclico/metabolismo , AMP Cíclico/metabolismo , Proteínas de Escherichia coli/metabolismo , Escherichia coli/enzimologia , Estabilidade de RNA , Ribonucleases/metabolismo , Adenilil Ciclases/genética , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Mutação , RNA Mensageiro/metabolismo , Ribonucleases/genética , Transcrição Gênica
19.
Genes Genet Syst ; 82(4): 291-9, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17895580

RESUMO

Escherichia coli ribonuclease LS is a potential antagonist of bacteriophage T4. When the T4 dmd gene is defective, RNase LS cleaves T4 mRNAs and antagonizes T4 reproduction. Our previous work demonstrated that E. coli rnlA is essential for RNase LS activity. Here we show that His-tagged RnlA cleaves T4 soc RNA at one of the sites also cleaved by RNase LS in a cell extract. The cleavage activities of His-tagged RnlA and the RNase LS activity in a cell extract were inhibited by Dmd encoded by T4 phage. Fractionation of the RNase LS activity in a cell extract showed that it sedimented through a sucrose density gradient as a 1000-kDa complex that included RnlA. Pull-down experiments revealed more than 10 proteins associated with His-tagged RnlA. Among these, triose phosphate isomerase exhibited a remarkable affinity to RnlA. These results suggest that RnlA plays a central role in RNase LS activity and that its activity is regulated by multiple components.


Assuntos
Endorribonucleases/metabolismo , Proteínas de Escherichia coli/metabolismo , Escherichia coli/enzimologia , RNA Bacteriano/metabolismo , Ribonucleases/metabolismo , Bacteriófago T4/genética , Bacteriófago T4/metabolismo , Histidina/metabolismo , Substâncias Macromoleculares/metabolismo , Oligopeptídeos/metabolismo , RNA Ligase (ATP)/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Virais/metabolismo
20.
J Hand Surg Am ; 31(6): 896-903, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16843147

RESUMO

PURPOSE: The anatomy of the extensor retinaculum of the wrist has been described previously; the purpose of this study was to describe the specific anatomy of the septal attachments on the radius and to investigate the mechanical strength of each septal attachment on the radius and each of the 6 compartments of the extensor retinaculum. METHODS: Thirty-four wrists from 24 fresh-frozen and 10 embalmed cadavers were used. First, anatomic measurements of the individual extensor retinaculum septums were performed with calipers and a 3-dimensional digitizer. Next each extensor retinaculum septum was excised as a bone-retinaculum-bone autograft and was tested in tension to failure with a materials testing machine. Finally the 6 extensor retinaculum compartments were tested to failure. RESULTS: Septum 1/2 had the largest radial surface area and septum 3/4 had the smallest. Septum 1/2 also was found to have the highest failure strength at 51.3 +/- 15.3 N. In compartment testing, compartments 1 and 2 had the highest overall resistance to failure and compartment 5 had the lowest. Compartment 6, which was thought to be the weakest because of clinically observed subluxation of the extensor carpi ulnaris tendon, had stronger failure data than expected. CONCLUSIONS: This study offers detailed analysis of the extensor retinaculum compartments and 3-dimensional anatomy of the septal attachments. Clinically this study lends insight to the strength of bone-retinaculum-bone autografts and the etiology of extensor carpi ulnaris subluxation.


Assuntos
Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Reticulina/fisiologia , Reticulina/ultraestrutura , Tendões/anatomia & histologia , Tendões/fisiologia , Articulação do Punho/anatomia & histologia , Articulação do Punho/fisiologia , Idoso , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos , Feminino , Consolidação da Fratura/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Fraturas do Rádio/fisiopatologia , Resistência à Tração , Traumatismos do Punho/fisiopatologia
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