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1.
J Eur Acad Dermatol Venereol ; 36(9): 1641-1647, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35470460

RESUMO

BACKGROUND: The exact incidence of infantile haemangiomas (IH) in the Chinese population is still unknown. A positive family history of IH was considered as a risk factor for the development of IH. OBJECTIVES: This study aims to investigate the incidence of IH in the Chinese population and the mechanism of family history increases the risk for IH development. METHODS: A total of 2489 women and their newborns were enrolled in the prospective study. All newborns were followed up for 12 months to determine whether they developed IH. In addition, 213 IH probands and their 174 siblings were enrolled in the study. The incidence of IH in siblings of the IH probands was investigated. Information regarding risk factors for IH and demographic data were collected on all children. RESULTS: Of the 2572 newborns, 58 IH were identified in 56 (2.2%) newborns. The majority of IH were located on the trunk (46.6%). Siblings of the IH probands were at increased risk for the development of IH (P = 0.024, relative risk 2.451), and the occurrence of prenatal risk factors for IH(P = 0.003) compared with the general population. CONCLUSIONS: Our study showed that the incidence of IH is 2.2% in the Chinese population. Siblings of the individuals with IH were at increased risk for the development of IH may be related to the family clustering of prenatal risk factors for IH. Further exploration of the mechanisms and common features of these prenatal risk factors may help to disclose the origin and pathogenesis of IH.


Assuntos
Hemangioma Capilar , Hemangioma , Criança , Análise por Conglomerados , Feminino , Hemangioma/epidemiologia , Hemangioma/genética , Humanos , Incidência , Recém-Nascido , Gravidez , Estudos Prospectivos , Fatores de Risco
3.
Genet Mol Res ; 15(1)2016 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-26909910

RESUMO

In regard to the affiliation mistake that was made during our correspondence in our manuscript, we write this letter in order to correct it as per my PhD requirements and this is the Final decision as I have no other option. The correction is only in the affiliation and should be: T.N. Mahmoud(1,2), P.F. Lin(1), F.L. Chen(1), J.H. Zhou(1), X.G. Wang(1), N. Wang(1), X. Li(1) and Y.P. Jin(1). (1)Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, Northwest A&F University, Yangling, Shaanxi, China. (2)Department of Animal Physiology and Biochemistry, Faculty of Veterinary Medicine, Nyala University, Nyala, South Darfur, Sudan.

4.
Genet Mol Res ; 14(4): 13595-602, 2015 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-26535673

RESUMO

Luman/CREB3 is a transcription factor that is a member of the cAMP-response-element-binding protein family of basic region-leucine zipper transcription factors. This protein interacts with host cell factor 1, which also associates with the herpes simplex virus protein VP16 to induce the transcription of herpes simplex virus. Currently, the physiological function of Luman/CREB3 in reproductive processes remains unclear. In this study, quantitative real-time PCR and immunofluorescence assays were used to investigate the expression and localization of Luman in mouse oocytes as well as in early embryonic development. Luman protein was detected in the germinal vesicle and metaphase II stage oocytes, and was distributed in the cytoplasm, nucleus, and polar body of the oocyte stage. However, Luman protein and mRNA expression levels were significantly (P < 0.05) increased before activation of the zygotic genome, and expression levels peaked in 4-cell embryos. Expression levels were significantly (P < 0.05) decreased following the 8-cell stage throughout the blastocyst stage. The Luman protein was also distributed in the nucleus and cytoplasm in the early preimplantation embryo and showed enhanced nuclear staining starting from the 2-cell stage embryo up to the 8-cell stage embryo. The differences in the expression and localization of Luman in mouse oocytes and early embryo suggested that Luman plays an important role in oocyte maturation and early embryonic development processes.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Embrião de Mamíferos/metabolismo , Animais , Implantação do Embrião/fisiologia , Feminino , Imunofluorescência , Camundongos , Oócitos/metabolismo , Gravidez , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real
5.
Genet Mol Res ; 14(4): 17587-98, 2015 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-26782403

RESUMO

Herp, a mammalian protein with a ubiquitin-like domain, can be strongly upregulated by endoplasmic reticulum (ER) stress during ER-associated protein degradation. However, the other cellular functions of Herp remain unclear. We explored the effect of Herp on ER stress and inflammatory responses in RAW 264.7 macrophages that had been exposed to tunicamycin or thapsigargin. We successfully constructed recombinant lentiviral vectors for Herp short-hairpin RNA (shRNA) expression to better understand the contribution made by Herp to other signaling pathways. Western blotting revealed that the recombinant Herp lentiviral shRNA vector significantly inhibited the expression of the Herp protein in the thapsigargin-treated RAW 264.7 macrophages. The reverse transcription quantitative polymerase chain reaction results showed that knockdown Herp inhibited the expression of ER stress-related genes during exposure to tunicamycin or thapsigargin. In RAW 264.7 macrophages, knockdown Herp markedly attenuated the expression of inflammatory cytokines when exposed to tunicamycin; however, it strongly enhanced the expression of inflammatory cytokines when exposed to thapsigargin. We concluded that Herp lentiviral shRNA vectors had been successfully constructed; knockdown Herp inhibited ER stress and had a different effect on inflammatory responses in RAW 264.7 macrophages depending on whether they were exposed to tunicamycin or thapsigargin.


Assuntos
Estresse do Retículo Endoplasmático/genética , Inflamação/genética , Proteínas de Membrana/genética , Animais , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Vetores Genéticos , Inflamação/patologia , Lentivirus/genética , Macrófagos/metabolismo , Macrófagos/patologia , Proteínas de Membrana/antagonistas & inibidores , Camundongos , RNA Interferente Pequeno/genética , Transdução de Sinais/efeitos dos fármacos , Tunicamicina/farmacologia
6.
Science ; 209(4453): 285-7, 1980 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-6155698

RESUMO

Both hybrids of mouse and human microcells and whole cell hybrids generated by the fusion of primary mouse cells and SV40-transformed human fibroblasts were used to establish the syntenic association of the murine cytoplasmic superoxide dismutase and the interferon sensitivity genes on mouse chromosome 16. This assignment adds two new markers to chromosome 16 and provides another example of an evolutionarily conserved linkage. This finding also provides an animal model both for cellular responsiveness to interferon and for Down's syndrome.


Assuntos
Cromossomos Humanos 16-18 , Genes , Células Híbridas/fisiologia , Interferons/farmacologia , Superóxido Dismutase/genética , Animais , Linhagem Celular , Transformação Celular Viral , Humanos , Células Híbridas/efeitos dos fármacos , Cariotipagem , Camundongos , Vírus 40 dos Símios
7.
Ophthalmic Physiol Opt ; 29(2): 173-81, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19236587

RESUMO

PURPOSE: To determine the accuracy of distance autorefractions obtained by two 'open field' devices, the Tracey Visual Function Analyzer and the Shin-Nippon NVision-K 5001, by comparison with subjective refraction. METHODS: Both eyes of 50 healthy phakic participants underwent subjective refraction. Autorefractions were then performed on undilated pupils using the Tracey and a modified Shin-Nippon autorefractor and these were repeated within 50 days. Agreement with subjective refraction was calculated for sphere, mean spherical equivalent (MSE) and cylindrical vectors J(0) and J(45). Intratest and intertest variability were also evaluated. RESULTS: The mean age of the participants was 37.4 years. Subjective refraction MSE ranged from -6.25 D to +3.62 D, mean -0.49 D +/- 1.79 D. Bias between subjective refraction and Tracey was -0.001 D, +0.045 D, +0.017 D, and -0.015 D for sphere, MSE, J(0) and J(45) respectively; these were not significant. Bias between subjective refraction and Shin-Nippon was +0.004 D, +0.033 D, +0.106 D, and -0.021 D; only the J(0) vector was significantly different (p < 0.0001) although this difference was small. Intratest variability for Tracey was low, measured at 0.189 D for sphere and 0.178 for MSE, and for the Shin-Nippon 0.099 D and 0.086 D respectively. Tracey intertest variability revealed small, statistically significant bias for sphere and MSE (+0.071 D and +0.070 D, p = 0.011, 0.013). Shin-Nippon reproducibility showed no significant bias. CONCLUSIONS: Autorefraction measurements captured by both the Tracey and Shin-Nippon devices agree well with subjective refraction. The Shin-Nippon shows lower intratest variability.


Assuntos
Movimentos Oculares/fisiologia , Refração Ocular/fisiologia , Erros de Refração/diagnóstico , Seleção Visual/instrumentação , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Adulto Jovem
8.
Acta Chir Belg ; 108(5): 503-7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19051456

RESUMO

OBJECTIVES: The purpose of this study was to quantify the effect of training on outcomes following colorectal cancer resections in a District General Hospital. PATIENTS AND METHODS: Data on 102 consecutive elective colorectal cancer resections performed at a District General Hospital over a three-year period were prospectively collated. The proportion of cases performed by trainees was recorded and the seniority of the operating surgeon was related to pre-operative morbidity, operative time and postoperative outcome. RESULTS: Consultants, staff grades and registrars performed 46, 35 and 21 procedures respectively. Of the cases performed by registrars, consultant supervision was provided in seven cases, with staff grades providing supervision in 14 cases. As compared with consultants, registrars were less likely to undertake anterior resection (p = 0.001). However, the mean operating times of trainees (145 +/- 8 mins) and consultants (135 +/- 6 mins) were similar. There were no significant differences between the groups with respect to postoperative mortality or morbidity. There was a trend towards more advanced disease in consultant cases, and consultants had a significantly poorer freedom from death or recurrence at two years as compared with trainees (p = 0.03). CONCLUSIONS: In our unit, trainees performed 21% of all elective colorectal resections with no detrimental effect on length of hospital stay, overall hospital costs and early and late patient outcomes. Major colorectal procedures can be successfully accomplished in a District General setting by trainees, with the training burden shared between consultants and staff grade surgeons.


Assuntos
Neoplasias Colorretais/cirurgia , Procedimentos Cirúrgicos do Sistema Digestório/estatística & dados numéricos , Cirurgia Geral/educação , Idoso , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Hospitais de Distrito , Hospitais Gerais , Humanos , Recidiva Local de Neoplasia , Avaliação de Resultados em Cuidados de Saúde , Complicações Pós-Operatórias , Estudos Prospectivos
9.
Mol Cell Biol ; 8(12): 5280-91, 1988 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3244356

RESUMO

We previously isolated and characterized the structure of murine thymidine kinase (tk) genomic and cDNA sequences to begin a study designed to identify regions of the tk gene important for regulated expression during the transition of cells from G0 to a proliferating state. In this report, we describe the stable transfection of the cloned gene into L-M(TK-) cells and show that both thymidine kinase (TK) enzyme activity and DNA synthesis increase in parallel when transfectants in G0 arrest are stimulated by serum. To define promoter and regulatory regions more precisely, we have constructed a series of tk minigenes and have examined their expression in stable transfectants after serum stimulation. We have identified a 291-base-pair DNA fragment at the 5' end of the tk gene that has promoter function, and we have determined its sequence. In addition, we have found that DNA sequences which mediate serum-induced expression of TK are transcribed, since expression of the murine tk cDNA, fused to a promoter from either the murine tk gene, the simian virus 40 early region, or the herpes simplex virus tk gene, is stimulated by serum. Our constructs also reveal that the murine tk polyadenylation signal is not required for regulation, nor is most of the 3' untranslated region. RNA dot blot analysis indicates that murine cytoplasmic tk mRNA levels always parallel TK enzyme activity. Nuclear runon transcription assays show less than a 2-fold increase in transcription from the cloned tk gene in serum-stimulated transfectants, but an 11-fold increase in mouse L929 cells, which are inherently TK+. These results taken together suggest that the murine tk gene is controlled in serum-stimulated cells by a transcriptional mechanism influenced by DNA sequences that flank tk and also by a posttranscriptional system linked to gene sequences that are transcribed.


Assuntos
Regulação da Expressão Gênica , Genes , Processamento Pós-Transcricional do RNA , Timidina Quinase/genética , Transcrição Gênica , Animais , Sequência de Bases , Sangue , Linhagem Celular , Clonagem Molecular , Meios de Cultura , Replicação do DNA , Cinética , Células L/enzimologia , Camundongos , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Timidina Quinase/metabolismo
10.
Mol Cell Biol ; 5(11): 3149-56, 1985 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3018504

RESUMO

Two functional cytosolic thymidine kinase (tk) cDNA clones were isolated from a mouse L-cell library. An RNA blot analysis indicated that one of these clones contains a nearly full-length tk sequence and that LTK- cells contain little or no TK message. The nucleotide sequences of both clones were determined, and the functional mouse tk cDNA contains 1,156 base pairs. An analysis of the sequence implied that there is an untranslated 32-nucleotide region at the 5' end of the mRNA, followed by an open reading frame of 699 nucleotides. The 3' untranslated region is 422 nucleotides long. Thus, the gene codes for a protein containing 233 amino acids, with a molecular weight of 25,873. A comparison of the coding sequences of the mouse tk cDNA with the human and chicken tk genes revealed about 86 and 70% homology, respectively. We also isolated the tk gene from a mouse C57BL/10J cosmid library. The structural organization was determined by restriction mapping, Southern blotting, and heteroduplex analysis of the cloned sequences, in combination with a mouse tk cDNA. The tk gene spans approximately 11 kilobases and contains at least five introns. Southern blot analysis revealed that this gene is deleted in mouse LTK- cells, consistent with the inability of these cells to synthesize TK message. This analysis also showed that tk-related sequences are present in the genomes of several mouse strains, as well as in LTK- cells. These segments may represent pseudogenes.


Assuntos
Clonagem Molecular , DNA/análise , Genes , Timidina Quinase/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Cosmídeos , Enzimas de Restrição do DNA , Células L/enzimologia , Camundongos , Hibridização de Ácido Nucleico
11.
Cancer Res ; 53(17): 4041-7, 1993 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-8358733

RESUMO

FET cells are well differentiated human adenocarcinoma cells whose growth is partially inhibited (50-60%) by transforming growth factor-beta 1 (TGF-beta 1). In exponentially growing cultures, TGF-beta 1 induces the expression of transforming growth factor-alpha (TGF-alpha) by 3-fold. To determine whether this induction is the result of increased TGF-alpha promoter activity, FET cells were transiently transfected with a plasmid containing 2816 base pairs of the 5'-flanking region of the TGF-alpha gene linked to luciferase. Transfected FET cells treated with growth-inhibitory concentrations of TGF-beta 1 (10 ng/ml) showed up to a 10-fold increase in luciferase activity. The increase in luciferase activity was dose dependent through the normal physiological range of TGF-beta 1 (0.5-20 ng/ml), saturating at 10 ng/ml. This effect was also TGF-alpha promoter specific, inasmuch as the Rous sarcoma virus long terminal repeat used as a control remained relatively insensitive to the effects of TGF-beta 1. By using progressively smaller portions of the TGF-alpha promoter region, the TGF-beta 1-responsive element was mapped between base pairs -77 and -201 of the 5'-flanking region. TGF-beta 1 treatment also affected epidermal growth factor receptor levels. FET cells treated with TGF-beta 1 (10 ng/ml) for 48 h showed a 20% decrease in the number of epidermal growth factor receptors and a 2-fold increase in the number of high affinity epidermal growth factor receptors on their surface. These results indicate that TGF-beta 1 acts as a positive regulator of TGF-alpha transcription, and they suggest a possible mechanism by which these cells circumvent the growth-inhibitory effects of TGF-beta 1.


Assuntos
Adenocarcinoma/metabolismo , Neoplasias do Colo/metabolismo , Fator de Crescimento Transformador alfa/biossíntese , Fator de Crescimento Transformador beta/farmacologia , Sequência de Bases , Meios de Cultura Livres de Soro , Indução Enzimática , Humanos , Luciferases/biossíntese , Luciferases/genética , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Transfecção , Fator de Crescimento Transformador alfa/química , Fator de Crescimento Transformador alfa/genética , Células Tumorais Cultivadas
12.
Antivir Ther ; 4(1): 21-8, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10682125

RESUMO

The current report summarizes the available published and unpublished data from several investigators on resistance in clinical isolates following prolonged stavudine therapy. Results suggest that stavudine resistance is both modest in degree and infrequent in appearance. Phenotypic evaluation of 61 patients on stavudine therapy showed only modest changes in drug sensitivity following up to 29 months of treatment. The post-treatment isolates from 15 patients exhibited an increase in EC50 value > fourfold (level above variability of assay) when compared with the corresponding pretreatment isolates. However, the vast majority (11) of these pretreatment isolates either had unexpectedly low EC50 levels and/or had post-treatment isolates that lacked any amino acid changes within their reverse transcriptase (RT) gene to account for the observed change in sensitivity. Of the four remaining isolates, two appeared to have a multi-resistant phenotype to several nucleoside analogues and two had no detectable RT amino acid changes to account for the observed change in stavudine sensitivity. To date, clinical HIV-1 isolates displaying stavudine-specific resistance have yet to be reported. Furthermore, full or partial RT sequence analysis of 194 post-treatment isolates failed to identify any consistent amino acid changes. The strain-specific V75T mutation reported to confer stavudine resistance to the HXB2 HIV-1 strain in vitro, was found in only six isolates and did not correlate with stavudine resistance. This low incidence of stavudine resistance is in striking contrast to that observed with other nucleoside analogues and further supports the use of stavudine in first-line combination therapy for HIV patients.


Assuntos
Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Fármacos Anti-HIV/uso terapêutico , Estavudina/uso terapêutico , Resistência a Medicamentos , HIV-1/efeitos dos fármacos , Humanos , Fenótipo , DNA Polimerase Dirigida por RNA/genética
13.
Curr Pharm Des ; 10(15): 1785-93, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15180540

RESUMO

BMS-378806 is a prototype of a new class of small molecule HIV-1 inhibitors that blocks viral attachment to cells. This compound exhibits potent inhibitory activity against a panel of HIV-1 laboratory and clinical isolates (M- and T-tropic), selective for HIV-1 and inactive against HIV-2, SIV and a panel of other viruses. BMS-378806 exhibits no significant cytotoxicity and displays many attractive pharmacological properties such as low protein binding, minimal serum effect on anti-HIV-1 potency, good oral bioavailability in animal species and a clean safety profile in initial animal toxicology studies. The compound binds to gp120 and blocks the attachment of the HIV-1 envelope protein to cellular CD4 receptors via a specific and competitive mechanism. BMS-378806 binds directly to gp120 at an approximately 1:1 stoichiometry, with a binding affinity similar to that of soluble CD4. Further confirmation that this class of compounds targets the envelope in infected cells was obtained through the isolation of resistant variants and the mapping of resistance substitutions to the HIV-1 envelope. In particular, two substitutions, M426L and M475I, are situated at or near the CD4 binding pocket of gp120. Recombinant HIV-1 carrying these two substitutions demonstrated significantly reduced susceptibility to inhibition. Using these HIV-1 gp120 resistant variants and gp120/CD4 contact site mutants, the potential BMS-378806 target site was localized to a specific region within the CD4 binding pocket of gp120. Together, the data show that BMS-378806 is the first of a new class of HIV inhibitors with the potential to become a valued addition to our current repertoire of antiretroviral drugs.


Assuntos
Fármacos Anti-HIV/farmacologia , Antígenos CD4/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Proteína gp120 do Envelope de HIV/metabolismo , HIV-1/efeitos dos fármacos , Animais , Fármacos Anti-HIV/metabolismo , HIV-1/metabolismo , Humanos , Piperazinas/metabolismo , Piperazinas/farmacologia , Ligação Proteica/efeitos dos fármacos
14.
J Med Chem ; 37(12): 1758-68, 1994 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-8021916

RESUMO

A series of HIV protease inhibitors containing a novel C2 symmetrical "aminodiol" core structure were prepared from amino acid starting materials. The ability of the aminodiols to inhibit HIV replication in cell culture is comparable to their ability to inhibit the isolated enzyme, a result compatible with good cell membrane penetration by this class of compounds. Optimization of the structure-activity in this series led to aminodiol 9a (Ki = 100 nM; ED50 (HIV-1) = 80 nM) containing P1/P1 benzyl and P2/P2 Boc substituents. Compound 9a is a selective inhibitor of HIV protease versus other aspartyl proteases such as human renin, human cathepsin D, and porcine pepsin. In addition, 9a is equipotent against HIV-1 and HIV-2 in cell culture and demonstrates similar activity in infected T-lymphocytes and PBMCs. After i.v. and oral administration in rats, 9a displayed significant oral bioavailability (ca. 40%) and a promising plasma elimination half-life (4 h).


Assuntos
Amino Álcoois/síntese química , Antivirais/síntese química , Desenho de Fármacos , Inibidores da Protease de HIV/síntese química , Protease de HIV/metabolismo , HIV/efeitos dos fármacos , Amino Álcoois/farmacologia , Animais , Antivirais/farmacologia , Células Cultivadas , HIV/enzimologia , Inibidores da Protease de HIV/farmacologia , HIV-1/efeitos dos fármacos , HIV-2/efeitos dos fármacos , Humanos , Masculino , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade , Suínos
15.
J Med Chem ; 39(10): 1991-2007, 1996 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-8642558

RESUMO

A series of novel aminodiol inhibitors of HIV protease based on the lead compound 1 with structural modifications at P1' were synthesized in order to reduce the cytotoxicity of 1. We have observed a high degree of correlation between the lipophilicity and cytotoxicity of this series of inhibitors. It was found that appropriate substitution at the para position of the P1' phenyl group of 1 resulted in the identification of equipotent (both against the enzyme and in cell culture) compounds (10l, 10m, 10n, and 15c) which possess significantly decreased cytotoxicity.


Assuntos
Aminas/síntese química , Inibidores da Protease de HIV/síntese química , Aminas/química , Aminas/farmacologia , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Inibidores da Protease de HIV/química , Inibidores da Protease de HIV/farmacologia , Humanos , Relação Estrutura-Atividade
16.
Biochem Pharmacol ; 60(7): 927-36, 2000 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-10974201

RESUMO

Six boronated tetrapeptides with the carboxy moiety of phenylalanine replaced by dihydroxyboron were synthesized, and their activities against human immunodeficiency virus 1 (HIV-1) protease subsequently investigated. The sequences of these peptides were derived from HIV-1 protease substrates, which included the C-terminal part of the scissile bond (Phe-Pro) within the gag-pol polyprotein. Enzymatic studies showed that these compounds were competitive inhibitors of HIV-1 protease with K(i) values ranging from 5 to 18 microM when experiments were performed at high enzyme concentrations (above 5 x 10(-8) M); however, at low protease concentrations inhibition was due in part to an increase of the association constants of the protease subunits. Ac-Thr-Leu-Asn-PheB inhibited HIV-1 protease with a K(i) of 5 microM, whereas the non-boronated parental compound was inactive at concentrations up to 400 microM, which indicates the significance of boronation in enzyme inhibition. The boronated tetrapeptides were inhibitory to an HIV-1 protease variant that is resistant to several HIV-1 protease inhibitors. Finally, fluorescence analysis showed that the interactions between the boronated peptide Ac-Thr-Leu-Asn-PheB and HIV-1 protease resulted in a rapid decrease of fluorescence emission at 360 nm, which suggests the formation of a compound/enzyme complex. Boronated peptides may provide useful reagents for studying protease biochemistry and yield valuable information toward the development of protease dimerization inhibitors.


Assuntos
Compostos de Boro/farmacologia , Inibidores da Protease de HIV/farmacologia , Protease de HIV/metabolismo , HIV/efeitos dos fármacos , Compostos de Boro/síntese química , Compostos de Boro/química , Sobrevivência Celular/efeitos dos fármacos , Resistência a Medicamentos , Inibidores da Protease de HIV/síntese química , Inibidores da Protease de HIV/química , Humanos , Peptídeos/síntese química , Peptídeos/química , Peptídeos/farmacologia , Espectrometria de Fluorescência , Células Tumorais Cultivadas
17.
Antiviral Res ; 22(2-3): 131-41, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7506510

RESUMO

A novel substituted naphthalenone (TGG-II-23A) has been found that inhibits HIV-1 infection of CEM-SS cells at concentrations that are not cytotoxic. Time of addition experiments indicate that TGG-II-23A functions at a stage of the HIV-1 life cycle at or near reverse transcription. Cell free assays confirmed that TGG-II-23A inhibits HIV-1 reverse transcriptase. Similar to other non-nucleoside inhibitors, TGG-II-23A was specific for HIV-1 and failed to inhibit the replication of HIV-2. The binding site of TGG-II-23A appears to be in close proximity to that of the TIBO-like inhibitors, since a TIBO-resistant HIV-1 was also resistant to TGG-II-23A treatment. TGG-II-23A is a mixed non-competitive inhibitor that exhibits the same template:primer selectivity as other non-nucleoside inhibitors. TGG-II-23A therefore represents a new structural entry into the TIBO/Nevirapine class of inhibitors of HIV-1 reverse transcriptase.


Assuntos
Antivirais/farmacologia , HIV-1/efeitos dos fármacos , Naftalenos/farmacologia , Oxazóis/farmacologia , Inibidores da Transcriptase Reversa , Benzodiazepinas/farmacologia , Linhagem Celular , Relação Dose-Resposta a Droga , Transcriptase Reversa do HIV , HIV-1/enzimologia , Humanos , Imidazóis/farmacologia , Nevirapina , Piridinas/farmacologia , Linfócitos T/citologia
18.
Brain Res ; 553(2): 300-4, 1991 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-1933287

RESUMO

Infection with the human immunodeficiency virus (HIV-1) often produces a set of neuropsychiatric dysfunctions which have been termed the AIDS dementia complex. This complex appears due to the infection of brain cells by HIV-1. If so, brain cells might be expected to contain a binding site for the same viral envelope glycoprotein that enables HIV-1 to bind to other cells (e.g. CD4+ T-cells), gp120. The present study shows that the cells of the brain-derived U-138MG, U-373MG, SK-N-MC and SK-N-SH cell lines bind gp120 in an inhibitable fashion. Binding of gp120 to these cells is inhibited by the dyes Aurintricarboxylic acid (ATA) and Evans blue (EB), which are known to inhibit specific gp120 and HIV-1 binding, and block HIV-1 infection, in CD4-expressing cells. Binding is not inhibited by Aurin, a dye related to ATA but lacking its anti-HIV effects. As expected, anti-CD4 antibodies are ineffective in blocking gp120 binding to brain-derived cells. These results suggest that human brain-derived cells possess a specific binding site for gp120 that is not the CD4 antigen.


Assuntos
Encéfalo/metabolismo , Antígenos CD4/imunologia , Proteína gp120 do Envelope de HIV/metabolismo , Anticorpos Monoclonais , Sítios de Ligação , Ligação Competitiva , Linhagem Celular , Glioma , Humanos , Cinética , Neuroblastoma , Proteínas Recombinantes/metabolismo , Células Tumorais Cultivadas
19.
Anticancer Res ; 12(1): 97-104, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1373593

RESUMO

1-(isoquinolinesulfonyl)-2-methylpiperazine dihydrochloride (H-7), a potent inhibitor of protein kinases, has been used as a tool to examine the role of protein kinases in a variety of cellular functions. Contingent on the cell type, H-7 has been reported either to inhibit or to promote differentiation. The biological effects of H-7 on human colon adenocarcinoma cells have not been reported. In this study we investigated the effects of H-7 on differentiation - related parameters such as cellular morphology, proliferation, the expression of carcinoembryonic antigen (CEA), fibronectin and cytokeratins in human adenocarcinoma cell lines HCT116 and SW480. H-7 induced pronounced morphological alterations in both cell lines. It induced fibronectin expression and down-modulated CEA expression and secretion in the SW480 cells, but not in the HCT116 cells. Expression of acidic keratins was not affected by H-7 treatment in both cell lines. However, the expression of basic keratins were down-modulated in the HCT116 cells and enhanced in the SW480 cells. These studies showed that the protein kinase inhibitor, H-7, modulated phenotypic properties in human colon adenocarcinoma cells. Alterations in phenotypic properties and their significance in regard to the induction of differentiation are discussed.


Assuntos
Adenocarcinoma/patologia , Neoplasias do Colo/patologia , Isoquinolinas/farmacologia , Piperazinas/farmacologia , Inibidores de Proteínas Quinases , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina , Adenocarcinoma/química , Antígeno Carcinoembrionário/análise , Diferenciação Celular , Divisão Celular/efeitos dos fármacos , Neoplasias do Colo/química , Fibronectinas/análise , Humanos , Queratinas/análise
20.
J Antibiot (Tokyo) ; 49(3): 234-40, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8626236

RESUMO

A fungal metabolite, BMS-182123, which inhibited bacterial endotoxin-induced production of tumor necrosis factor (TNF-alpha) in murine macrophages and human peripheral blood monocytes (in vitro), was isolated from the culture broth of Penicillium chrysogenum strain V39673. The effective BMS-182123 concentration (IC50) resulting in 50% inhibition of lipopolysaccharide-induced TNF-alpha production in murine macrophages and human monocytes was 600 ng/ml and 4.0 microgram/ml, respectively. BMS-182123 suppressed the lipopolysaccharide-induced TNF-alpha promoter activity and did not affect the stability of posttranscriptional mRNA. Addition of hydrophobic resin, Amberlite XAD-8 (1%), to the fermentation enhanced the production of BMS-182123 by 5.5 fold. A total of 577 mg pure BMS-182123 was recovered from a 250-liter fermentation supplemented with 1% Amberlite XAD-8.


Assuntos
Hidrocarbonetos Aromáticos com Pontes/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Penicillium/metabolismo , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/biossíntese , Animais , Sequência de Bases , Hidrocarbonetos Aromáticos com Pontes/química , Hidrocarbonetos Aromáticos com Pontes/metabolismo , Sondas de DNA/genética , Fermentação , Humanos , Técnicas In Vitro , Lipopolissacarídeos/farmacologia , Camundongos , Dados de Sequência Molecular , Estrutura Molecular , Penicillium/classificação , Regiões Promotoras Genéticas/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fator de Necrose Tumoral alfa/genética
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