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1.
Crit Rev Immunol ; 44(4): 41-49, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38505920

RESUMO

Non-tuberculous mycobacteria (NTM) infection is common in bronchiectasis, with rising incidence globally. However, investigation into NTM in bronchiectasis patients in China remains relatively limited. This work aimed to identify and understand the features of NTM in bronchiectasis patient in Fuzhou district of China. The pulmonary samples were collected from 281 bronchiectasis patients with suspected NTM infection in Fuzhou, 2018-2022. MPB64 antigen detection was employed for the preliminary evaluation of NTM. Further NTM identification was realized using gene chip and gene sequencing. Among 281 patients, 172 (61.21%) patients were NTM-positive (58.72%) according to MPB64 antigen detection, with females (58.72%) outnumbering males (41.28%) and the highest prevalence in the age group of 46-65 years. In total, 47 NTM single infections and 3 mixed infections (1 Mycobacterium tuberculosis complex-M. intracellulare, 1 M. avium-M. intracellulare, and 1 M. abscessus-M. intracellulare) were identified through multicolor melting curve analysis (MMCA), which was compared with gene sequencing results. Both methods suggested Mycobacterium (M.) intracellulare, M. abscessus, and M. avium as the primary NTM species affecting bronchiectasis patients. M. intracellulare and M. abscessus were more frequent in females than males with the highest prevalence in the age group of 46-65 years according to MMCA. This research provides novel insights into the epidemiological and clinical features of NTM in bronchiectasis patients in Southeastern China. Significantly, M. intracellulare, M. abscessus, and M. avium were identified as the major NTM species, contributing to a better understanding and management of bronchiectasis accompanied by NTM infection.


Assuntos
Bronquiectasia , Infecções por Mycobacterium não Tuberculosas , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Idoso , Micobactérias não Tuberculosas/genética , Infecções por Mycobacterium não Tuberculosas/diagnóstico , Infecções por Mycobacterium não Tuberculosas/epidemiologia , Infecções por Mycobacterium não Tuberculosas/complicações , Bronquiectasia/diagnóstico , Bronquiectasia/epidemiologia , Bronquiectasia/complicações , Complexo Mycobacterium avium/genética , Hospitais , China/epidemiologia
2.
China Tropical Medicine ; (12): 139-2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-979606

RESUMO

@#Abstract:Objective To investigate the clinical characteristics and early diagnostic methods of patients with Talaromyces marneffei infection, so as to reduce the mortality of patients. Methods The clinical characteristics and microbiological analysis data including fungal culture, smear examination and mass spectrometry were collected from 18 patients with Talaromyces marneffei infection in the Department of Respiratory Medicine, Department of Tuberculosis, and Department of Critical Respiratory Medicine in Fuzhou Pulmonary Hospital from January 2017 to December 2021, and descriptive analysis was conducted. Results All the 18 patients were confirmed to be infected with Talaromyces marneffei by conventional culture and matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry (MS). The main infection sites of 18 patients with Talaromyces marneffei infection were lungs and lymph nodes, and the patients were accompanied by clinical manifestations such as cough, sputum and fever. The imaging features such as patchy shadows, mediastinal lymph node shadows and nodular shadows were common. Microbiological testing showed a statistically significant difference between smear and culture with a higher positive culture rate (χ2=13.74, P<0.05). The positive rate of blood culture in microbiological test was 60.0% (9/15), the positive rate of bronchial lavage fluid culture was 26.7% (4/15), the positive rate of sputum culture was 5.6% (1/18), one case each of pus, bone marrow, pleural fluid and cerebrospinal fluid was positive for culture and the other cases were negative, one case of sputum and one case of pus were positive for smear and the rest were negative. Colony characteristics showed that the colony morphology was mycelial phase at 25 ℃, producing red pigment, and the branching pattern of the penicillus was seen microscopically as monoverticillate or biverticillate; At 35 ℃, the yeast phase appeared at the initial stage, and then the mycelium phase changed after 5-6 days; the yeast phase was observed at 37 ℃, and yeast-like cells were seen under the microscope. All 18 patients with Talaromyces marneffei infection got better after using antifungal drugs. Compared with non-HIV patients with Talaromyces marneffei infection, leukopenia and anemia were common in HIV patients with Talaromyces marneffei infection, and the differences were statistically significant (P<0.05).  Conclusions The infection of Talaromyces marneffei can be divided into localized type and disseminated type, which usually invade the lungs, skin, lymph nodes and other places. The main manifestations of patients are fever, cough, phlegm and other atypical symptoms. At present, the diagnosis of Talaromyces marneffei infection is mostly based on the fungal culture test, and the application of MALDI-TOF MS method can effectively shorten the diagnosis time of Talaromycosis marneffei. Clinical characteristics combined with microbiological analysis provide an objective basis for early diagnosis of patients with Talaromyces marneffei infection, and timely use of antifungal therapy can improve the prognosis of patients.

3.
BMC Psychiatry ; 22(1): 618, 2022 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-36123674

RESUMO

BACKGROUND: Neutrophil-lymphocyte ratio (NLR), monocyte-lymphocyte ratio (MLR), and platelet-lymphocyte ratio (PLR) are blood indicators of systemic inflammation. This study aims to compare the levels of inflammatory indicators derived from blood routine tests between adolescents with non-suicidal self-injury (NSSI) and those with non-NSSI. METHODS: A total of 201 adolescents with mood or emotional disorders were enrolled in this study, among which 106 had engaged in NSSI and 95 had never engaged in NSSI. NLR, MLR, and PLR were calculated based on the complete blood cell count. RESULTS: There was no significant difference in demographic data between the two groups. The NSSI group exhibited significantly higher MLR (P = 0.001) and PLR (P = 0.007) than the non-NSSI group. Multivariate logistic regression analysis revealed that MLR (OR 1.545, 95%CI [1.087-2.281], P = 0.021) and PLR (OR 1.327, 95%CI [1.215-1.450], P < 0.001) were independently associated with NSSI. Receiver operating characteristic (ROC) curve analyses demonstrated that for differentiating NSSI from non-NSSI, the optimal cut-off value of MLR was 0.135 and the area under curve was 0.638 ([0.561- 0.715], P < 0.001), with a sensitivity of 90.60% and a specificity of 33.70%; the optimal cut-off value of PLR was 127.505 and the area under curve was of 0.611 ([0.533-0.689], P < 0.001), with a sensitivity of 39.60% and a specificity of 81.10%. CONCLUSIONS: Systemic inflammation, as indicated by elevated MLR and PLR, was found to be strongly associated with NSSI among adolescents.


Assuntos
Monócitos , Comportamento Autodestrutivo , Adolescente , Humanos , Inflamação , Linfócitos , Prognóstico , Estudos Retrospectivos , Comportamento Autodestrutivo/diagnóstico
4.
Ann Palliat Med ; 10(6): 6438-6445, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34154354

RESUMO

BACKGROUND: Nontuberculous mycobacteria (NTM) are mycobacteria other than mycobacterium tuberculosis complex (MTBC) and mycobacterium leprae. NTM can cause infection in many human tissues and organs and is most commonly seen in the lungs. Clinically, the symptoms and signs of nontuberculous mycobacteria lung disease (NMLD) are very similar to those of tuberculosis (TB). Because most NTMs are resistant to conventional anti-TB drugs, the rapid diagnosis of NMLD is the key to treatment. This study aimed to use gene chip technology to examine bronchoalveolar lavage fluid (BALF) from NMLD patients to explore the value of this technique for the rapid diagnosis of NMLD in BALF. METHODS: A retrospective analysis of 308 patients with NMLD treated at Fuzhou Pulmonary Hospital from January 2018 to June 2020 was performed. BALF was collected from the patients. Gene chip detection (Capital Bio Corporation, Chengdu, China) and BACTEC MGIT960 (Becton, Dickinson and Company, MD, USA) liquid culture were performed to compare the NTM positive detection rates between the two methods. The NTM strain isolated from liquid culture were identified by rDNA sequencing and the results of identification were compared with those of gene chip detection using BALF specimens. RESULTS: A total of 221 cases of NTM were detected in 308 BALF specimens by the gene chip method; the positive rate was 71.75% (221/308). A total of 218 cases of NTM were detected by the liquid culture method, and the positive rate was 70.78% (218/308). There was no significant difference in the positive rate of NTM detected in BALF specimens between the two methods (χ2=0.138 P=0.804>0.05); 187 cases were detected with both sequencing and gene chip detection, and the coincidence rate of strain identification with the two methods reached 96.79% (181/187). Sequencing of 218 strains of NTM was carried out; eight species were identified, and the top four species were M. intracellulare (131/218, 60.09%), M. avium (48/218, 22.02%), M. abscessus (27/218, 12.38%), and M. kansasii (5/218, 2.29%). CONCLUSIONS: Gene chip technology can rapidly detect NTM in BALF and accurately identify bacterial species. It has important clinical value in the early diagnosis and treatment of NMLD.


Assuntos
Pneumopatias , Líquido da Lavagem Broncoalveolar , China , Humanos , Pneumopatias/diagnóstico , Pneumopatias/genética , Análise de Sequência com Séries de Oligonucleotídeos , Estudos Retrospectivos
5.
Bioorg Med Chem ; 28(22): 115734, 2020 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-33007551

RESUMO

The evolution of gamma-secretase modulators (GSMs) through the introduction of novel heterocycles with the goal of aligning activity for reducing the levels of Aß42 and properties consistent with a drug-like molecule are described. The insertion of a methoxypyridine motif within the tetracyclic scaffold provided compounds with improved activity for arresting Aß42 production as well as improved properties, including solubility. In vivo pharmacokinetic analysis demonstrated that several compounds within the novel series were capable of crossing the BBB and accessing the therapeutic target. Treatment with methoxypyridine-derived compound 64 reduced Aß42 levels in the plasma of J20 mice, in addition to reducing Aß42 levels in the plasma and brain of Tg2576 mice.


Assuntos
Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Desenho de Fármacos , Inibidores Enzimáticos/farmacologia , Piridinas/farmacologia , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/análise , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/biossíntese , Animais , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Feminino , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Estrutura Molecular , Piridinas/síntese química , Piridinas/química , Relação Estrutura-Atividade
6.
J Med Chem ; 61(1): 84-97, 2018 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-28992413

RESUMO

Hearing loss is a major public health concern with no pharmaceutical intervention for hearing protection or restoration. Using zebrafish neuromast hair cells, a robust model for mammalian auditory and vestibular hair cells, we identified a urea-thiophene carboxamide, 1 (ORC-001), as protective against aminoglycoside antibiotic (AGA)-induced hair cell death. The 50% protection (HC50) concentration conferred by 1 is 3.2 µM with protection against 200 µM neomycin approaching 100%. Compound 1 was sufficiently safe and drug-like to validate otoprotection in an in vivo rat hearing loss model. We explored the structure-activity relationship (SAR) of this compound series to improve otoprotective potency, improve pharmacokinetic properties and eliminate off-target activity. We present the optimization of 1 to yield 90 (ORC-13661). Compound 90 protects mechanosensory hair cells with HC50 of 120 nM and demonstrates 100% protection in the zebrafish assay and superior physiochemical, pharmacokinetic, and toxicologic properties, as well as complete in vivo protection in rats.


Assuntos
Aminoglicosídeos/efeitos adversos , Perda Auditiva/induzido quimicamente , Perda Auditiva/prevenção & controle , Segurança , Tiofenos/química , Tiofenos/farmacologia , Ureia/química , Administração Oral , Animais , Avaliação Pré-Clínica de Medicamentos , Ratos , Relação Estrutura-Atividade , Tiofenos/administração & dosagem , Tiofenos/efeitos adversos , Peixe-Zebra
7.
Tuberculosis (Edinb) ; 107: 5-12, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29050772

RESUMO

T cell immune responses have played pivotal roles in host immune protection against Mycobacterium tuberculosis (MTB) infection. MTB specific antigen, Rv3615c (EspC), was identified to be as immunodominant as the well-known ESAT-6 and CFP-10, and has brought promising expectations to more sensitive T-cell based diagnosis and vaccine development. However, limited knowledge about the immunogenicity and diagnostic values of this antigen has restricted its application in clinical practice. Herein, the Rv3615c antigen was identified as a robust CTL immunoantigen with broadly cross-human leucocyte antigen (HLA) allele recognized peptides which may contribute to the broad recognition of Rv3615c antigen among the population. A three-antigen-cocktail (3-Ag-cocktail) comprising of ESAT-6, CFP-10 and Rv3615c was investigated in a multicenter, randomized and double-blinded study to evaluate its clinical diagnostic performances. A significantly improved sensitivity was demonstrated against the 3-Ag-cocktail compared with that against ESAT-6 and CFP-10. Both responsive magnitude and sensitivity were significantly lower in patients concurrently suffering from cancer, indicating its restriction in diagnosis of immunocomprised patients. In conclusion, inclusion of the Rv3615c antigen with multiple HLA restricted CTL epitopes would benefit the T-cell based diagnosis of MTB infection.


Assuntos
Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Mycobacterium tuberculosis/imunologia , Linfócitos T Citotóxicos/imunologia , Tuberculose/diagnóstico , Adolescente , Adulto , Idoso , Células Cultivadas , China , Método Duplo-Cego , ELISPOT , Feminino , Antígenos HLA-A/imunologia , Interações Hospedeiro-Patógeno , Humanos , Hospedeiro Imunocomprometido , Epitopos Imunodominantes , Testes de Liberação de Interferon-gama , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Linfócitos T Citotóxicos/microbiologia , Tuberculose/imunologia , Tuberculose/microbiologia , Adulto Jovem
8.
Bioorg Med Chem Lett ; 19(4): 1245-9, 2009 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-19147348

RESUMO

Versatile intermediates 12'-iodovinblastine, 12'-iodovincristine and 11'-iodovinorelbine were utilized as substrates for transition metal based chemistry which led to the preparation of novel analogues of the vinca alkaloids. The synthesis of key iodo intermediates, their transformation into final products, and the SAR based upon HeLa and MCF-7 cell toxicity assays is presented. Selected analogues 27 and 36 show promising anticancer activity in the P388 murine leukemia model.


Assuntos
Antineoplásicos Fitogênicos/síntese química , Vimblastina/análogos & derivados , Alcaloides de Vinca/síntese química , Alcaloides de Vinca/farmacologia , Vincristina/análogos & derivados , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Modelos Animais de Doenças , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Leucemia P388 , Camundongos , Estrutura Molecular , Relação Estrutura-Atividade , Vimblastina/síntese química , Vimblastina/química , Vimblastina/farmacologia , Alcaloides de Vinca/química , Vincristina/síntese química , Vincristina/química , Vincristina/farmacologia
9.
Bioorg Med Chem ; 14(4): 1247-54, 2006 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-16242337

RESUMO

The Z- and E-2-fluoro- and 2-chloropurine methylenecyclopropanes 9a,b and 10a,b as well as enantiomeric Z-isoguanine methylenecyclopropanes 11a,b and their phenyl phosphoralaninate pronucleotides 11c,d were synthesized and their antiviral activity against several viruses was evaluated. Fluoro analogues 9a and 10a were active against human cytomegalovirus but they were cytotoxic at approximately the same concentrations. Chloro derivatives 9b and 10b were non-cytotoxic and effective against Epstein-Barr virus in Daudi cells. Isoguanine analogues 11a-d lacked antiviral activity but pronucleotides 11c,d were substrates for porcine liver esterase. From the group of 9a,b and 10a,b, the fluoro analogues 9a and 10a exhibited antitumor activity but only the Z-isomer 9a had a selective effect.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Antivirais/síntese química , Antivirais/farmacologia , Ciclopropanos/química , Nucleosídeos/química , Nucleosídeos/farmacologia , Animais , Antineoplásicos/química , Antivirais/química , Linhagem Celular Tumoral , Humanos , Hidrólise , Espectroscopia de Ressonância Magnética , Camundongos , Estrutura Molecular , Nucleosídeos/síntese química , Nucleotídeos/química , Purinas/química , Relação Estrutura-Atividade
10.
Artigo em Inglês | MEDLINE | ID: mdl-14565285

RESUMO

Synthesis and biological activity of 7- and 9-isomers (Z+E) of methylenecyclopropane analogues of 2-aminopurine nucleosides is described. The (S,Z)-9-isomer is a substrate for xanthine oxidase.


Assuntos
2-Aminopurina/análogos & derivados , 2-Aminopurina/síntese química , 2-Aminopurina/química , 2-Aminopurina/metabolismo , Antivirais/síntese química , Antivirais/química , Ciclopropanos , Indicadores e Reagentes , Isomerismo , Especificidade por Substrato , Xantina Oxidase/metabolismo
11.
Nucleosides Nucleotides Nucleic Acids ; 22(3): 265-74, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12816385

RESUMO

Synthesis of (Z)-(2,3-bis-hydroxymethyl)methylenecyclopropane analogues of nucleosides adenosine 10a, 10b, 10c and 17 is described. Epimerization of Feist's acid (11) using acetic anhydride gave cyclic anhydride 12 which was reduced in situ to give diol 13. Acetylation (compound 14) followed by addition of bromine led to dibromo derivative 15. Alkylation-elimination of adenine with 15 afforded, after deacetylation, analogue 10a. Similar treatment of 2-amino-6-chloropurine and 2,6-diaminopurine led to diacetates 16 and 18. Deprotection then gave compounds 17 and 10c. Hydrolysis of 17 furnished guanine analogue 10b. Compounds 10a, 10b or 10c were inactive against HCMV, HSV-1, HSV-2, EBV VZV and HBV. Analogues 10a and 10b were also assayed for anti-HIV activity. Compound 10a was effective in HIV-1/MT-2 culture with EC50/CC50 33/> 100 microM but 10b was inactive. Analogue 10a was not a substrate for adenosine deaminase.


Assuntos
Ciclopropanos/síntese química , Nucleosídeos de Purina/síntese química , Fármacos Anti-HIV/síntese química , Fármacos Anti-HIV/química , Fármacos Anti-HIV/farmacologia , Ciclopropanos/química , HIV-1/efeitos dos fármacos , Modelos Químicos , Estrutura Molecular , Nucleosídeos de Purina/química , Estereoisomerismo , Relação Estrutura-Atividade
12.
Nucleosides Nucleotides Nucleic Acids ; 22(2): 135-44, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12744601

RESUMO

Synthesis and biological activity of racemic 2-aminopurine methylenecyclopropane analogues of nucleosides 4, 5, 10 and 11 is described. One-pot alkylation-elimination of 2-aminopurine (6) with dibromide 7 gave a mixture of four isomeric methylenecyclopropanes. The (E, Z)-N9 and (E, Z)-N7 isomers 8 and 9 were resolved by chromatography on silica gel. Deacetylation of 8 afforded the respective (Z)-N9 and (E)-N9 isomers 4 and 10 which were separated by chromatography on silica gel. In a similar fashion, (E, Z)-N7 mixture 9 furnished (Z)-N7 and (E)-N7 isomers 5 and 11. The S-(+)-enantiomer 4 was obtained by desulfurization of (S)-(+)-6-thiosynguanol (13) with Raney Ni. Compound 13 was obtained from (S)-(+)-2-amino-6-chloro derivative 12 and NaSH in methanol. Racemic analogues 4, 5, 10 and 11 were inactive against HCMV, HSV-1, HSV-2, EBV and VZV. Enantiomer (S)-(+)-4 inhibited replication of HSV-1 in BSC-1 cells (ELISA) with EC50 35 microM and it was non-cytotoxic in KB cells (CC50 > 100 microM). Compound (S)-(+)-4 was also moderately effective against VZV in HFF culture with EC50/CC50 (microM) 60/>460 and it was a substrate for xanthine oxidase.


Assuntos
2-Aminopurina/análogos & derivados , Ciclopropanos/química , Nucleosídeos/síntese química , Alquilação , Antivirais/síntese química , Cromatografia em Gel , Modelos Químicos , Ressonância Magnética Nuclear Biomolecular , Nucleosídeos/metabolismo , Pró-Fármacos/química , Espectrofotometria Ultravioleta , Estereoisomerismo , Xantina Oxidase/química , Xantina Oxidase/metabolismo
13.
J Med Chem ; 46(8): 1531-7, 2003 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-12672254

RESUMO

A series of 13 new (S,Z)-2-aminopurine methylenecyclopropane analogues was synthesized, and their antiviral activity was investigated. The nucleophilic displacement of chlorine of 2-amino-6-chloropurine derivative 5 with allyl-, propargyl-, cyclopropylmethyl-, isopropyl-, benzyl-, cyclohexyl-, and 2-hydroxyethylamine gave N(6)-alkyl compounds 2a, 2b, 2c, 2d, 2e,2f, and 2g. A similar reaction of 5 with allyl, cyclopropylmethyl, propyl, or pentyl alcohol catalyzed by K(2)CO(3) afforded O(6)-alkyl analogues 3a, 3c, 3h and 3i. Propane- and pentanethiol furnished S(6)-alkyl compounds 4h and 4i. The N(6)-alkyl derivatives 2a, 2b, O(6) analogues 3a, 3c, 3h, 3i, and S(6) compounds 4h, 4i which were highly effective in all CMV assays and exhibited the lowest cytotoxicity in proliferating HFF cells appear to be good candidates for in vivo assays. Activity of new analogues against HSV-1 or HSV-2 was restricted to BSC-1 and Vero cultures. Compounds 2c, 2b, 3a and 3h were effective against EBV in one of two assays (Daudi or H-1). Analogues 3a and 4i were the most active anti-VZV agents whereas compounds 3h, 3i, and 4h inhibited the replication of HBV in a micromolar concentration range.


Assuntos
Aminopirina/análogos & derivados , Aminopirina/síntese química , Antivirais/síntese química , Ciclopropanos/síntese química , Vírus da Hepatite B/efeitos dos fármacos , Herpesviridae/efeitos dos fármacos , Nucleosídeos de Purina/síntese química , Aminopirina/química , Aminopirina/farmacologia , Animais , Antivirais/química , Antivirais/farmacologia , Linhagem Celular , Chlorocebus aethiops , Ciclopropanos/química , Ciclopropanos/farmacologia , Ensaio de Imunoadsorção Enzimática , Humanos , Camundongos , Nucleosídeos de Purina/química , Nucleosídeos de Purina/farmacologia , Estereoisomerismo , Relação Estrutura-Atividade , Ensaio de Placa Viral
14.
Nucleosides Nucleotides Nucleic Acids ; 22(12): 2105-19, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14714760

RESUMO

We have reported previously that purine methylenecyclopropane analogs are potent agents against cytomegaloviruses. In an attempt to extend the activity of these compounds, the 2-amino-6-cyclopropylaminopurine analog, QYL-1064, was selected for further study by modifying the purine 6 substituent. A total of 22 analogs were tested against herpes simplex virus types 1 and 2 (HSV-1, HSV-2), varicella zoster virus (VZV), human cytomegalovirus (HCMV), murine cytomegalovirus (MCMV), Epstein-Barr virus (EBV), human herpesvirus type 6 (HHV-6) and human herpesvirus type 8 (HHV-8). Ten of the analogs had activity against at least one of the viruses tested. One compound had moderate activity against HSV-1 and six had activity against VZV. All but one compound was active against HCMV with a mean EC50 of 2.1 +/- 0.6 microM, compared with a mean EC50 of 3.9 +/- 0.8 microM for ganciclovir. Of special interest was the fact that eight of the ten compounds were active against both HHV-6A and HHV-6B with mean EC50 values of 6.0 +/- 5.2 mciroM and <2.4 +/- 1.5 microM, respectively. Only two compounds had activity against EBV, whereas all but one compound was active against HHV-8 with a mean EC50 of 3.1 +/- 1.7 microM. These results indicate that members of this series of methylenecyclopropane analogs are highly active against HCMV, HHV-6, and HHV-8 but are less active against HSV, VZV, and EBV.


Assuntos
Adenosina/análogos & derivados , Antivirais/farmacologia , Guanosina/análogos & derivados , Herpesviridae/efeitos dos fármacos , Antivirais/química , Divisão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Ciclopropanos/química , Citomegalovirus/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Fibroblastos/virologia , Herpesvirus Humano 1/efeitos dos fármacos , Herpesvirus Humano 2/efeitos dos fármacos , Herpesvirus Humano 3/efeitos dos fármacos , Herpesvirus Humano 4/efeitos dos fármacos , Herpesvirus Humano 6/efeitos dos fármacos , Herpesvirus Humano 8/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Testes de Sensibilidade Microbiana , Estrutura Molecular , Muromegalovirus/efeitos dos fármacos
15.
Bioorg Med Chem ; 10(9): 3049-55, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12110328

RESUMO

Enzymatic generation of nitric oxide (NO) by nitric oxide synthase (NOS) consists of two oxidation steps. The first step converts L-arginine to N(G)-hydroxy-L-arginine (NOHA), a key intermediate, and the second step converts NOHA to NO and L-citrulline. To fully probe the substrate specificity of the second enzymatic step, an extensive structural screening was carried out using a series of N-alkyl (and N-aryl) substituted-N'-hydroxyguanidines (1-14). Among the eleven N-alkyl-N'-hydroxyguanidines evaluated, N-n-propyl (2), N-iso-propyl (3), N-n-butyl (4), N-s-butyl (5), N-iso-butyl (6), N-pentyl (8) and N-iso-pentyl (9) derivatives were efficiently oxidized by the three isoenzymes of NOS (nNOS, iNOS and eNOS) to generate NO. N-Butyl-N'-hydroxyguanidine (4) was the best substrate for iNOS (K(m)=33 microM) and N-iso-propyl-N'-hydroxyguanidine (3) was the best substrate for nNOS (K(m)=56 microM). When the alkyl substituents were too small (such as ethyl 1) or too large (such as hexyl 10 and cyclohexyl 11), the activity decreased significantly. This suggests that the van der Waals interaction between the alkyl group and the hydrophobic cavity in the NOS active site contributes significantly to the relative reactivity of compounds 3-11. Moreover, five N-aryl-N'-hydroxyguanidines were found to be good substrates for iNOS, but not substrates for eNOS and nNOS. N-phenyl-N'-hydroxyguanidine was the best substrate among them (K(m)=243 microM). This work demonstrates that N-alkyl substituted hydroxyguanidine compounds are novel NOS substrates which 'short-circuit' the first oxidation step of NOS, and N-aryl substituted hydroxyguanidine compounds are isoform selective NOS substrate.


Assuntos
Óxido Nítrico Sintase/metabolismo , Animais , Guanidinas/síntese química , Guanidinas/metabolismo , Humanos , Hidroxilaminas , Concentração Inibidora 50 , Cinética , Camundongos , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II , Óxido Nítrico Sintase Tipo III , Oxirredução , Ratos , Relação Estrutura-Atividade , Especificidade por Substrato
16.
J Org Chem ; 67(1): 286-9, 2002 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-11777473

RESUMO

Absolute configurations of enantiomeric methylenecyclopropanecarbinols obtained by reaction of (R)- and (S)-epichlorohydrin 5 with methylenetriphenylphosphorane or resolution of the corresponding oxaphospholane 6 via a salt with L-(+)-tartaric acid and subsequent Wittig transformation with formaldehyde were revised. The (-)-oxaphospholane 6 has the S,S and (-)-(methylenecyclopropyl)carbinol (4) the R configuration. The configurations of (+)-6 and (+)-4 are then R,R and S, respectively. These assignments are in accord with an initial attack of phosphorane at the oxirane ring of epichlorohydrin. An improved preparation of key enantiomeric intermediates (R)-1a and (S)-1a, important for synthesis of antiviral purine methylenecyclopropane analogues of nucleosides, is also described.


Assuntos
Adenina/análogos & derivados , Antivirais/síntese química , Ciclopropanos/química , Metanol/análogos & derivados , Metanol/química , Antivirais/química , Epicloroidrina/química , Estrutura Molecular , Nucleosídeos/química , Fosforanos/química , Estereoisomerismo
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