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1.
Allergy ; 72(6): 896-907, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27861994

RESUMO

BACKGROUND: Delayed-type ß-lactam hypersensitivity develops in subset of patients. The cellular immunological processes that underlie the drug-specific response have been described; however, little is known about involvement of the humoral immune system. Thus, the aim of this study was to utilize piperacillin hypersensitivity as an exemplar to (i) develop cell culture methods for the detection of drug-specific B-cell responses, (ii) characterize drug-specific IgG subtypes and (iii) assess reactivity of IgG antibodies against proteins modified to different levels with piperacillin haptens. METHODS: IgG secretion and CD19+ CD27+ expression on B cells were measured using ELISPOT and flow cytometry, respectively. A piperacillin-BSA adduct was used as an antigen in ELISA antibody binding studies. Adducts generated using different ratios of drug to protein were used to determine the degree of conjugation required to detect IgG binding. RESULTS: B cells from hypersensitive patients, but not controls, were stimulated to secrete IgG and increase CD27 expression when cultured with soluble piperacillin. A piperacillin-BSA adduct with cyclized and hydrolysed forms of the hapten bound to eight lysine residues was used to detect hapten-specific IgG 1-4 subclasses in patient plasma. Hapten inhibition and the use of structurally unrelated hapten-BSA adducts confirmed antigen specificity. Antibody binding was detected with antigens generated at piperacillin/BSA ratios of 10:1 and above, which corresponded to a minimum epitope density of 1 for antibody binding. CONCLUSION: These data show that antigen-specific B lymphocytes and T lymphocytes are activated in piperacillin-hypersensitive patients. Further work is needed to define the role different IgG subtypes play in regulating the iatrogenic disease.


Assuntos
Linfócitos B/imunologia , Hipersensibilidade a Drogas , Imunoglobulina G/imunologia , beta-Lactamas/imunologia , Antibacterianos/imunologia , Especificidade de Anticorpos , Estudos de Casos e Controles , Haptenos/imunologia , Humanos , Ativação Linfocitária , Piperacilina/imunologia
2.
J Fish Dis ; 40(4): 485-494, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27451953

RESUMO

Fusarium oxysporum species complex (FOSC) is a highly diverse fungus. Recently, F. oxysporum infection was identified from zebrafish (Danio rerio) culturing system in Korea. Initially, a rapid whitish smudge was appeared in the water with the fungal blooming on walls of fish tanks. Microscopic studies were conducted on fungal hyphae, colony pigmentation and chlamydospore formation and the presence of macro- and microspores confirmed that the isolated fungus as F. oxysporum. Furthermore, isolated F. oxysporum was confirmed by internal transcribed spacer sequencing which matched (100%) to nine F. oxysporum sequences available in GenBank. Experimental hypodermic injection of F. oxysporum into adult zebrafish showed the development of fungal mycelium and pathogenicity similar to signs observed. Histopathologic results revealed a presence of F. oxysporum hyphae in zebrafish muscle. Fusarium oxysporum growth was increased with sea salt in a concentration-dependent manner. Antifungal susceptibility results revealed that F. oxysporum is resistant to copper sulphate (up to 200 µg mL-1 ) and sensitive to nystatin (up to 40 µg mL-1 ). This is the first report of FOSC from zebrafish culture system, suggesting it appears as an emerging pathogen, thus posing a significant risk on zebrafish facilities in the world.


Assuntos
Doenças dos Peixes/microbiologia , Fusariose/veterinária , Fusarium/fisiologia , Peixe-Zebra , Animais , DNA Intergênico/genética , Doenças dos Peixes/prevenção & controle , Fusariose/microbiologia , Fusariose/prevenção & controle , Fusarium/classificação , Fusarium/genética , Fusarium/isolamento & purificação , Filogenia , Análise de Sequência de DNA/veterinária
3.
Clin Exp Allergy ; 45(8): 1305-16, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25851465

RESUMO

BACKGROUND: For certain HLA allele-associated drug hypersensitivity reactions, the parent drug has been shown to associate directly with the risk allele. In other forms of hypersensitivity, HLA risk alleles have not been identified and T cells are activated in an allele unrestricted manner. Chemically reactive drug metabolites bind to multiple proteins; thus, it is assumed that the derived peptide antigens interact with a number of HLA molecules to activate T cells; however, HLA restriction of the drug metabolite-specific T-cell response has not been studied. OBJECTIVE: To utilize T cells from sulfamethoxazole (SMX) hypersensitive patients with cystic fibrosis to examine the HLA molecules that interact with nitroso SMX (SMX-NO)-derived antigens. METHODS: T-cell clones were generated from 4 hypersensitive patients. Drug-specific proliferative responses and cytokine secretion were measured. Anti-human class I and class II antibodies were used to analyse HLA restriction. Antigen-presenting cells expressing different HLA molecules were used to determine the alleles involved in the presentation of SMX-NO-derived antigens to T cells. RESULTS: A total of 976 clones were tested for SMX-NO reactivity. Thirty-nine CD4+ clones were activated with SMX-NO and found to proliferate and secrete cytokines. The SMX-NO-specific response was blocked with an antibody against HLA-DQ. SMX-NO-specific responses were detected with antigen-presenting cells expressing HLA-DQB1*05:01 (patient 1) and HLA-DQB1*02:01 (patient 2), but not other HLA-DQB1 alleles. CONCLUSION AND CLINICAL RELEVANCE: HLA-DQ plays an important role in the activation of SMX-NO-specific CD4+ T cells. Detection of HLA-DQ allele-restricted responses suggests that T cells are activated by a limited repertoire of SMX-NO-modified peptides.


Assuntos
Alelos , Linfócitos T CD4-Positivos/imunologia , Proliferação de Células/efeitos dos fármacos , Fibrose Cística/imunologia , Hipersensibilidade a Drogas/imunologia , Cadeias beta de HLA-DQ/imunologia , Ativação Linfocitária/efeitos dos fármacos , Sulfametoxazol/análogos & derivados , Linfócitos T CD4-Positivos/patologia , Proliferação de Células/genética , Fibrose Cística/genética , Fibrose Cística/patologia , Hipersensibilidade a Drogas/genética , Hipersensibilidade a Drogas/patologia , Feminino , Cadeias beta de HLA-DQ/genética , Humanos , Ativação Linfocitária/genética , Masculino , Sulfametoxazol/efeitos adversos , Sulfametoxazol/farmacologia
4.
Br J Surg ; 102(2): e124-32, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25627125

RESUMO

BACKGROUND: The aim was to establish the feasibility of using a tissue stabilization gel (Allprotect™) as an alternative to liquid nitrogen to facilitate collection of clinical samples for translational research. METHODS: Tumour samples from patients undergoing surgery for primary or metastatic colorectal cancer were either snap-frozen in liquid nitrogen or stored in Allprotect™ under a number of different conditions. Sample integrity was compared across different storage conditions by assessing biomolecule stability and function. DNA quality was assessed spectrophotometrically and by KRas genotyping by pyrosequencing. Total RNA retrieval was determined by nanodrop indices/RNA integrity numbers, and quality assessed by reverse transcription-PCR for two representative genes (high-mobility group box 1, HMGB1; carboxylesterase 1, CES1) and two microRNAs (miR122 and let7d). Western blot analysis of HMGB1 and CES1 was used to confirm protein expression, and the metabolic conversion of irinotecan to its active metabolite, SN-38, was used to assess function. RESULTS: Under short-term storage conditions (up to 1 week) there was no apparent difference in quality between samples stored in Allprotect™ and those snap-frozen in liquid nitrogen. Some RNA degradation became apparent in tissue archived in Allprotect™ after 1 week, and protein degradation after 2 weeks. CONCLUSION: In hospitals that do not have access to liquid nitrogen and -80°C freezers, Allprotect™ provides a suitable alternative for the acquisition and stabilization of clinical samples. Storage proved satisfactory for up to 1 week, allowing transfer of samples without the need for specialized facilities. Surgical relevance Access to clinical material is a fundamental component of translational research that requires significant infrastructure (research personnel, liquid nitrogen, specialized storage facilities). The aim was to evaluate a new-to-market tissue stabilization gel (Allprotect™), which offers a simple solution to tissue preservation without the need for complex infrastructure. Allprotect™ offers comparable DNA, RNA and protein stabilization to tissue snap-frozen in liquid nitrogen for up to 1 week. Degradation of biomolecules beyond this highlights its role as a short-term tissue preservative. Allprotect™ has the potential to increase surgeon participation in translational research and surgical trials requiring tissue collection.


Assuntos
Géis/farmacologia , Preservação de Tecido/métodos , Pesquisa Translacional Biomédica/métodos , Análise de Variância , Neoplasias Colorretais/cirurgia , DNA/metabolismo , Estudos de Viabilidade , Humanos , RNA/metabolismo , Manejo de Espécimes/métodos
5.
Spinal Cord ; 53(11): 827-34, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26123207

RESUMO

STUDY DESIGN: Experimental study. OBJECTIVES: To study the role of surface temperature as an adjunct to motor evoked potentials (MEPs) in rabbit spinal cord injury (SCI) model. SETTING: Department of Orthopedics, Korea University Guro Hospital, Seoul, Korea. METHODS: Rabbits (n =18) were divided into Complete (n = 9) and Incomplete (n = 9) SCI groups. Complete SCI was defined as being non-responsive to a wake-up test with loss of MEPs after transection of spinal cord. Incomplete SCI was defined as being responsive to a wake-up test with significant attenuation (⩾ 80%) of MEPs after impaction on spinal cord. Surface temperature of upper and lower extremities, core temperature and MEPs signals were checked before, during and after SCI for 20 min. A wake-up test was conducted and spinal cord was histologicaly evaluated. RESULTS: Experimental conditions between the two groups were statistically similar (P > 0.005 for all values). After SCI, upper extremity temperatures did not change in either group (P > 0.005); however, the surface temperature of the lower extremities in the Complete SCI Group elevated to 1.7 ± 0.5°C in comparison to 0.5 ± 0.1°C in the Incomplete SCI Group (P < 0.001). The scores of wake-up test in the Incomplete SCI Group were significantly different from that of the Complete SCI Group (P < 0.001), while white and gray matter damage was variable on histology. CONCLUSIONS: Monitoring of changes of body surface temperature of the lower extremities can be potentially used to identify the completeness of SCI in a rabbit model.


Assuntos
Temperatura Corporal/fisiologia , Modelos Animais de Doenças , Potencial Evocado Motor/fisiologia , Traumatismos da Medula Espinal/fisiopatologia , Animais , Eletroencefalografia , Masculino , Músculo Esquelético/fisiopatologia , Medição da Dor , Coelhos
6.
Br J Cancer ; 108(6): 1245-51, 2013 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-23449357

RESUMO

BACKGROUND: This phase 3 study evaluated the efficacy of new adjuvant chemotherapy (MFP), which intensified the mitomycin-C (MMC) plus short-term doxifluridine (Mf) for gastric cancer. PATIENTS AND METHODS: A total of 855 patients (424 in Mf, 431 in MFP) with pathological stage II-IV (M0) gastric cancer after D2 gastrectomy were randomly assigned to receive either Mf (MMC 20 mg m(-2), followed by oral doxifluridine 460-600 mg m(-2) per day for 3 months) or MFP (MMC 20 mg m(-2), followed by oral doxifluridine 460-600 mg m(-2) per day for 12 months with 6 monthly infusions of 60 mg m(-2) of cisplatin) chemotherapy. RESULTS: With a median follow-up of 6.6 years, there was no difference between the two groups in recurrence-free survival (RFS) (5-year RFS 61.1% in Mf and 57.9% in MFP; hazard ratio 1.10 (95% CI 0.89-1.35); P=0.39) and overall survival (OS) (5-year OS 66.5% in Mf and 65.0% in MFP; hazard ratio 1.11 (95% CI 0.89-1.39); P=0.33). CONCLUSION: Intensification of Mf adjuvant chemotherapy by prolonging the duration of oral fluoropyrimidine and adding cisplatin was safe but not effective to improve the survivals in curatively resected gastric cancer patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Recidiva Local de Neoplasia/tratamento farmacológico , Neoplasias Gástricas/tratamento farmacológico , Adolescente , Adulto , Idoso , Cisplatino/administração & dosagem , Feminino , Floxuridina/administração & dosagem , Seguimentos , Gastrectomia , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Mitomicina/administração & dosagem , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/cirurgia , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/cirurgia , Taxa de Sobrevida , Fatores de Tempo , Adulto Jovem
7.
J Appl Microbiol ; 115(2): 517-26, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23607518

RESUMO

AIMS: Atopic dermatitis (AD) is an inflammatory skin disease. Probiotics have been reported to modulate immune responses and thus are now being suggested as potential treatments for allergies. In this study, we investigated the inhibitory effects of Lactobacillus sakei probio 65 isolated from Kimchi on artificially inducing AD in NC/Nga mice. METHODS AND RESULTS: Oral administration of viable or heat-inactivated Lact. sakei probio 65 improved the condition of skin and reduced scratching frequency. Serum levels of IgE and cutaneous T-cell-attracting chemokine (CTACK) were significantly decreased by this therapy. Dead Lact. sakei probio 65 also decreased IL-4 and IL-6 serum concentrations. Moreover, both live and dead Lact. sakei probio 65 inhibited the expression of Thymus and activation-regulated chemokine and CTACK in AD-like skin lesions. The increased levels of Foxp3 expression in the lesional skin and ears were also suppressed by Lact. sakei probio 65. In addition, Lact. sakei probio 65 inhibited ß-hexosaminidase release and the secretion of IL-4, TNF-α and IL-6 from RBL-2H3 cells. CONCLUSIONS: Oral treatment with both viable and heat-inactivated Lact. sakei probio 65 inhibits skin inflammation and AD-like skin lesions, as well as mast cell activation. SIGNIFICANCE AND IMPACT OF THE STUDY: Lactobacillus sakei probio 65 has an inhibitory effect on atopic dermatitis-like skin lesions and may represent an effective new anti-inflammatory agent.


Assuntos
Dermatite Atópica/terapia , Lactobacillus , Probióticos/uso terapêutico , Animais , Linhagem Celular Tumoral , Dermatite Atópica/imunologia , Dermatite Atópica/patologia , Imunoglobulina E/sangue , Interleucina-4/sangue , Interleucina-6/sangue , Masculino , Camundongos , Pele/efeitos dos fármacos , Pele/patologia , Fator de Necrose Tumoral alfa/metabolismo
8.
Allergy ; 67(1): 58-66, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21933197

RESUMO

BACKGROUND: Up to 10% of patients with severe immune-mediated drug hypersensitivity reactions have tendencies to develop multiple drug hypersensitivities (MDH). The reason why certain individuals develop MDH and the underlying pathomechanism are unclear. We investigated different T cell subpopulations in MDH patients and compared them with patients allergic to a single drug and with healthy controls (HC). METHODS: We analyzed the in vitro reactivity of peripheral blood mononuclear cells from MDH patients (n=7), patients with hypersensitivity to a single drug (monoallergic, n=6), and healthy controls (HD) (n=6) to various drugs (mainly antibiotics and antiepileptics). By depleting and selectively re-adding CD4(+) CD25(bright) T cells (T regulatory cells, Treg), their effect on drug-specific T cell reactivity was analyzed. The phenotype of reacting T cells was determined ex vivo by staining for markers of activation (CD38) and cell exhaustion (PD-1). RESULTS: No functional deficiency of Treg cells was observed in all drug-allergic patients. Drug-reactive T cells from MDH patients were found in the CD4(+) CD25(dim) T cell fraction and showed enhanced CD38 and PD-1 expression, while those from monoallergic patients reside in the resting CD4(+) CD25(neg) T cell fraction. CONCLUSION: In patients with MDH, the drug-reactive T cells are contained in an in vivo pre-activated T cell fraction. Therefore, they may show a lower threshold for activation by drugs. The reason for this in vivo T cell pre-activation needs further investigations.


Assuntos
Hipersensibilidade a Drogas/imunologia , Ativação Linfocitária/imunologia , Subpopulações de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia , Separação Celular , Células Cultivadas , Citometria de Fluxo , Humanos , Separação Imunomagnética , Imunofenotipagem
9.
Arch Virol ; 157(2): 369-73, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22038073

RESUMO

Due to the need to track and monitor genetic diversity, the genome of the infectious hypodermal and hematopoietic necrosis virus (IHHNV) strain KLV-2010-01 in cultured Litopenaeus vannamei shrimp that originated from the first Korean outbreak in 2010 was sequenced and analyzed. The genome, with a length of 3914 nucleotides, was sequenced from the Korean IHHNV. The genome encoded three large and overlapping open reading frames: ORF1 (NS-1) of 2001 bp, ORF2 (NS-2) of 1092 bp and ORF3 (capsid protein) of 990 bp. The overall organization, size and predicted amino acid sequence of the three ORFs in Korean IHHNV were highly similar to those of members of the infectious IHHNV group, and the most closely related strains were IHHNVs described from Ecuador and Hawaii. Additionally, phylogenetic analysis showed that the Korean IHHNV was clustered with lineage III in the infectious IHHNV group and was most similar to IHHNV isolates from Ecuador, China and Taiwan.


Assuntos
Densovirinae/genética , Densovirinae/isolamento & purificação , Surtos de Doenças/veterinária , Genômica , Penaeidae/virologia , Animais , Sequência de Bases , Densovirinae/classificação , Genoma Viral , Dados de Sequência Molecular , Fases de Leitura Aberta , Penaeidae/crescimento & desenvolvimento , Filogenia , República da Coreia/epidemiologia
10.
Asian-Australas J Anim Sci ; 25(11): 1546-52, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25049515

RESUMO

A feeding experiment with 40 lactating Holstein cows and 4 dietary treatments was conducted to investigate supplementation with different levels of alcohol fermented feed to the TMR on lactating performance, blood metabolites, milk fatty acid profile and cholesterol concentration of blood and milk. Forty Holstein lactating cows (106±24 d post-partum; mean±SD) were distributed into four groups and randomly assigned to one of four treatments with each containing 10 cows per treatment. The treatment supplemented with TMR (DM basis) as the control (CON), and CON mixed with alcohol-fermented feeds (AFF) at a level of 5%, 10% and 15% of the TMR as T1, T2 and T3, respectively. Dry matter intake and milk yield were not affected by supplementation of AFF. An increased 4% FCM in the milk occurred in cows fed T3 diet compared with CON, while T1 and T2 diets decreased 4% FCM in a dose dependent manner. Supplementation of AFF increased the concentration of albumin, total protein (TP), ammonia, and high density lipoprotein-cholesterol in serum compared with CON. In contrast, supplementation with AFF clearly decreased concentration of blood urea nitrogen (BUN) and total cholesterol (TC) compare with CON. AFF supplementation increased the proportion of C18:1n9 and C18:2n6 compared to CON. A decrease in the concentration of saturated fatty acid (SFA) for T1, T2 and T3 resulted in an increased unsaturated fatty acid (USFA) to SFA ratio compared to CON. Concentration of cholesterol in milk fat was reduced in proportion to the supplemental level of AFF. Feeding a diet supplemented with a moderate level AFF to lactating cows could be a way to alter the feed efficiency and fatty acid profile of milk by increasing potentially human consumer healthy fatty acid without detrimental effects on feed intake and milk production. A substantially decreased cholesterol proportion in milk induced by supplementation AFF suggests that alcohol fermented feed may improve milk cholesterol levels without any negative effects in lactating cows.

11.
J Gen Virol ; 92(Pt 10): 2350-2355, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21715595

RESUMO

In the past 4 years, incidences of endemic or epidemic respiratory diseases associated with canine influenza H3N2 virus in Asian dogs have been reported in countries such as South Korea and China. Canine species were considered to be the new natural hosts for this virus. However, at the beginning of 2010, influenza-like respiratory signs, such as dyspnoea, were also observed among cats as well as in dogs in an animal shelter located in Seoul, South Korea. The affected cats showed 100 % morbidity and 40 % mortality. We were able to isolate a virus from a lung specimen of a dead cat, which had suffered from the respiratory disease, in embryonated-chicken eggs. The eight viral genes isolated were almost identical to those of the canine influenza H3N2 virus, suggesting interspecies transmission of canine influenza H3N2 virus to the cat. Moreover, three domestic cats infected with intranasal canine/Korea/GCVP01/07 (H3N2) all showed elevated rectal temperatures, nasal virus shedding and severe pulmonary lesions, such as suppurative bronchopneumonia. Our study shows, for the first time, that cats are susceptible to canine influenza H3N2 infection, suggesting that cats may play an intermediate host role in transmitting the H3N2 virus among feline and canine species, which could lead to the endemic establishment of the virus in companion animals. Such a scenario raises a public health concern, as the possibility of the emergence of new recombinant feline or canine influenza viruses in companion animals with the potential to act as a zoonotic infection cannot be excluded.


Assuntos
Doenças do Gato/epidemiologia , Doenças do Gato/virologia , Doenças do Cão/transmissão , Doenças do Cão/virologia , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Infecções por Orthomyxoviridae/veterinária , Animais , Temperatura Corporal , Doenças do Gato/mortalidade , Doenças do Gato/patologia , Gatos , Análise por Conglomerados , Doenças do Cão/epidemiologia , Doenças do Cão/patologia , Cães , Fezes/virologia , Vírus da Influenza A Subtipo H3N2/classificação , Vírus da Influenza A Subtipo H3N2/genética , Pulmão/virologia , Dados de Sequência Molecular , Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/virologia , Filogenia , RNA Viral/genética , República da Coreia/epidemiologia , Análise de Sequência de DNA , Eliminação de Partículas Virais
12.
J Viral Hepat ; 18(10): e432-8, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21914060

RESUMO

No studies have reported the long-term effects of entecavir switching in patients with multidrug resistance who developed resistance after lamivudine/adefovir sequential therapy. We evaluated the efficacy of 96 weeks of entecavir therapy in patients with resistance to lamivudine/adefovir sequential therapy. In total, 33 patients with chronic hepatitis B virus (HBV) infection with evidence of active viral replication (HBV DNA levels ≥ 10(5) copies/mL) or a history of treatment failure to lamivudine/adefovir sequential therapy between April 2007 and July 2009 were treated with entecavir (1.0 mg daily) for at least 48 weeks. The rates of alanine transaminase (ALT) normalization and HBV DNA negativity were 66.7% (14/21) and 24.2% (8/33) at 48 weeks, respectively. The initial HBV DNA level was the only factor that was inversely associated with serum HBV DNA negativity after 48 weeks of entecavir therapy (P < 0.023). At 96 weeks, the rates of ALT normalization and HBV DNA negativity were 77.8% (7/9) and 16.7% (3/18), respectively. Viral breakthrough occurred in 21.2% (7/33) and 78.9% (15/19) of patients at 48 and 96 weeks, respectively. Patients who achieved a HBV DNA level of <4 log(10) copies/mL at 48 weeks maintained a similar HBV DNA level and a normal ALT level until 96 weeks. Entecavir monotherapy for 96 weeks was not efficacious for patients with lamivudine/adefovir-resistant HBV. The initial HBV DNA level was the only predictive factor for antiviral efficacy. However, patients who achieved a HBV DNA level of <4 log(10) copies/mL with a normal ALT level at 48 weeks should maintain, rather than stop, entecavir therapy.


Assuntos
Antivirais/administração & dosagem , Farmacorresistência Viral , Guanina/análogos & derivados , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B Crônica/tratamento farmacológico , Adenina/administração & dosagem , Adenina/análogos & derivados , Adulto , Idoso , Alanina Transaminase/sangue , Antivirais/farmacologia , DNA Viral/sangue , Feminino , Guanina/administração & dosagem , Humanos , Lamivudina/farmacologia , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Organofosfonatos/administração & dosagem , Estudos Retrospectivos , Resultado do Tratamento , Carga Viral
13.
Handb Exp Pharmacol ; (196): 165-94, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20020263

RESUMO

Drugs are generally converted to biologically inactive forms and eliminated from the body, principally by hepatic metabolism. However, certain drugs undergo biotransformation to metabolites that can interfere with cellular functions through their intrinsic chemical reactivity towards glutathione, leading to thiol depletion, and functionally critical macromolecules, resulting in reversible modification, irreversible adduct formation, and irreversible loss of activity. There is now a great deal of evidence which shows that reactive metabolites are formed from drugs known to cause hepatotoxicity, such as acetaminophen, tamoxifen, isoniazid, and amodiaquine. The main theme of this article is to review the evidence for chemically reactive metabolites being initiating factors for the multiple downstream biological events culminating in toxicity. The major objectives are to understand those idiosyncratic hepatotoxicities thought to be caused by chemically reactive metabolites and to define the role of toxic metabolites.


Assuntos
Transformação Celular Neoplásica/induzido quimicamente , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Radicais Livres/metabolismo , Neoplasias Hepáticas/induzido quimicamente , Fígado/efeitos dos fármacos , Animais , Biotransformação , Transformação Celular Neoplásica/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Humanos , Fígado/metabolismo , Neoplasias Hepáticas/metabolismo , Medição de Risco , Transdução de Sinais/efeitos dos fármacos
14.
Spinal Cord ; 48(11): 838-9, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20351743

RESUMO

STUDY DESIGN: Case report. OBJECTIVE: To report on the need to consider the possibility of the superior mesenteric artery syndrome (SMAS) even after a long time from the initial spinal cord injury. SETTING: Ulsan, South Korea. METHODS: A 41-year-old man with complete tetraplegia was evaluated for nausea and vomiting. He had a cervical cord injury 11 years previously and his body mass index was 18.6 on admission. The contrast-enhanced abdominal computed tomography (CT) showed intestinal obstruction at the third-portion of the duodenum. With frequent position change and intravenous electrolyte support, the symptoms resolved. There was no relapse of the symptoms with some lifestyle modifications. CONCLUSION: Patients with spinal cord injury may develop SMAS even long after their initial injury.


Assuntos
Quadriplegia/complicações , Traumatismos da Medula Espinal/complicações , Síndrome da Artéria Mesentérica Superior/etiologia , Adulto , Humanos , Masculino , Posicionamento do Paciente/normas , Postura/fisiologia , Fatores de Risco , Síndrome da Artéria Mesentérica Superior/terapia , Fatores de Tempo , Resultado do Tratamento
15.
Br J Cancer ; 101(7): 1145-54, 2009 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-19724273

RESUMO

BACKGROUND: High levels of S100A6 have been associated with poor outcome in pancreatic cancer patients. The functional role of S100A6 is, however, poorly understood. METHODS: Immunoprecipitation followed by two-dimensional gel electrophoresis and mass spectrometry were undertaken to identify S100A6 interacting proteins in pancreatic cancer cells. Immunohistochemistry and coimmunofluorescence were performed to examine expression or colocalisation of proteins. siRNA was used to deplete specific proteins and effects on motility were measured using Boyden Chamber and wound healing assays. RESULTS: Our proteomic screen to identify S100A6 interacting proteins revealed annexin 11, annexin 2, tropomyosin beta and a candidate novel interactor lamin B1. Of these, annexin 2 was considered particularly interesting, as, like S100A6, it is expressed early in the development of pancreatic cancer and overexpression occurs with high frequency in invasive cancer. Reciprocal immunoprecipitation confirmed the interaction between annexin 2 and S100A6 and the proteins colocalised, particularly in the plasma membrane of cultured pancreatic cancer cells and primary pancreatic tumour tissue. Analysis of primary pancreatic cancer specimens (n=55) revealed a strong association between high levels of cytoplasmic S100A6 and the presence of annexin 2 in the plasma membrane of cancer cells (P=0.009). Depletion of S100A6 was accompanied by diminished levels of membrane annexin 2 and caused a pronounced reduction in the motility of pancreatic cancer cells. CONCLUSION: These findings point towards a functional role for S100A6 that may help explain the link between S100A6 expression in pancreatic cancer and aggressive disease.


Assuntos
Anexina A2/metabolismo , Proteínas de Ciclo Celular/fisiologia , Neoplasias Pancreáticas/patologia , Proteínas S100/fisiologia , Anexina A2/análise , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Citoplasma/química , Humanos , Imunoprecipitação , Neoplasias Pancreáticas/química , Interferência de RNA , Proteína A6 Ligante de Cálcio S100
16.
J Pharmacol Exp Ther ; 331(2): 372-81, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19666748

RESUMO

Antigen-presenting cells (APC) are thought to play an important role in the pathogenesis of drug-induced immune reactions. Various pathological factors can activate APC and therefore influence the immune equilibrium. It is interesting that several diseases have been associated with an increased rate of drug allergy. The aim of this project was to evaluate the impact of such "danger signals" on sulfamethoxazole (SMX) metabolism in human APC (peripheral blood mononuclear cells, Epstein-Barr virus-modified B lymphocytes, monocyte-derived dendritic cells, and two cell lines). APC were incubated with SMX (100 microM-2 mM; 5 min-24 h), in the presence of pathological factors: bacterial endotoxins (lipopolysaccharide and staphylococcal enterotoxin B), flu viral proteins, cytokines [interleukin (IL)-1beta, IL-6, IL-10; tumor necrosis factor-alpha; interferon-gamma; and transforming growth factor-beta], inflammatory molecules (prostaglandin E2, human serum complement, and activated protein C), oxidants (buthionine sulfoximine and H(2)O(2)), and hyperthermia (37.5-39.5 degrees C). Adduct formation was evaluated by enzyme-linked immunosorbent assay and confocal microscopy. SMX-protein adduct formation was time- and concentration-dependent for each cell type tested, in both physiological and danger conditions. A danger environment significantly increased the formation of SMX-protein adducts and significantly shortened the delay for their detection. An additive effect was observed with a combination of danger signals. Dimedone (chemical selectively binding cysteine sulfenic acid) and antioxidants decreased both baseline and danger-enhanced SMX-adduct formation. Various enzyme inhibitors were associated with a significant decrease in SMX-adduct levels, with a pattern varying depending on the cell type and the culture conditions. These results illustrate that danger signals enhance the formation of intracellular SMX-protein adducts in human APC. These findings might be relevant to the increased frequency of drug allergy in certain disease states.


Assuntos
Anti-Infecciosos/metabolismo , Células Apresentadoras de Antígenos/imunologia , Células Apresentadoras de Antígenos/metabolismo , Hipersensibilidade a Drogas/imunologia , Imunidade/efeitos dos fármacos , Sulfametoxazol/metabolismo , Anti-Infecciosos/imunologia , Linfócitos B/metabolismo , Linhagem Celular , Cicloexanonas , Citocinas/farmacologia , Células Dendríticas/metabolismo , Endotoxinas/farmacologia , Inibidores Enzimáticos/farmacologia , Ensaio de Imunoadsorção Enzimática , Febre/metabolismo , Herpesvirus Humano 4/imunologia , Humanos , Mediadores da Inflamação/farmacologia , Microscopia Confocal , Monócitos/metabolismo , Orthomyxoviridae/química , Oxidantes/farmacologia , Sulfametoxazol/imunologia , Proteínas Virais/farmacologia
17.
Xenobiotica ; 39(8): 565-77, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19621999

RESUMO

Adverse drug reactions, in particular drug-induced hepatotoxicity, represent a major challenge for clinicians and an impediment to safe drug development. Novel blood or urinary biomarkers of chemically-induced hepatic stress also hold great potential to provide information about pathways leading to cell death within tissues. The earlier pre-clinical identification of potential hepatotoxins and non-invasive diagnosis of susceptible patients, prior to overt liver disease is an important goal. Moreover, the identification, validation and qualification of biomarkers that have in vitro, in vivo and clinical transferability can assist bridging studies and accelerate the pace of drug development. Drug-induced chemical stress is a multi-factorial process, the kinetics of the interaction between the hepatotoxin and the cellular macromolecules are crucially important as different biomarkers will appear over time. The sensitivity of the bioanalytical techniques used to detect biological and chemical biomarkers underpins the usefulness of the marker in question. An integrated analysis of the biochemical, molecular and cellular events provides an understanding of biological (host) factors which ultimately determine the balance between xenobiotic detoxification, adaptation and liver injury. The aim of this review is to summarise the potential of novel mechanism-based biomarkers of hepatic stress which provide information to connect the intracellular events (drug metabolism, organelle, cell and whole organ) ultimately leading to tissue damage (apoptosis, necrosis and inflammation). These biomarkers can provide both the means to inform the pharmacologist and chemist with respect to safe drug design, and provide clinicians with valuable tools for patient monitoring.


Assuntos
Biomarcadores/sangue , Biomarcadores/urina , Doença Hepática Induzida por Substâncias e Drogas/sangue , Doença Hepática Induzida por Substâncias e Drogas/urina , Estresse Fisiológico/efeitos dos fármacos , Xenobióticos/efeitos adversos , Apoptose/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/patologia , Desenho de Fármacos , Fígado , Necrose/sangue , Necrose/induzido quimicamente , Necrose/urina , Xenobióticos/farmacologia
18.
Vet Res Commun ; 33(2): 139-47, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18651234

RESUMO

A miniarray system was developed for the simultaneous detection of porcine circovirus type 1 (PCV1) and type 2 (PCV2) in pigs. The system consists of a polymerase chain reaction (PCR) step to amplify target viral DNA, followed by detection of the amplified DNA using a membrane-anchored probe array and an avidin-alkaline phosphatase (Av-AP) indicator system. The lower limit of detection of PCV using the miniarray was 10(1.9) tissue culture infectious dose 50 (TCID(50))/ml and 10(2.08)TCID(50)/ml for PCV1 and PCV2, respectively, and 100 viral copies/microl for both PCV1 and PCV2. We validated the miniarray system using 141 lymph node specimens from pigs with suspected postweaning multisystemic wasting syndrome or porcine dermatitis and nephropathy syndrome. Of the 141 samples evaluated, 55 were identified as positive for PCV by the miniarray. Relative to in situ hybridization, the sensitivity and specificity of the miniarray was 100% and 98.9%, respectively. In contrast to other microarray systems, the miniarray does not require a DNA chip reader, since the results can be determined by visual inspection of colorized spots on a nylon membrane. This system represents an effective alternative method for the differential detection of PCV1 and PCV2 in pigs, as well as the maintenance of PCV-free cell lines and pre-screening of commercial vaccines for possible contamination.


Assuntos
Infecções por Circoviridae/veterinária , Circovirus/isolamento & purificação , Análise de Sequência com Séries de Oligonucleotídeos/veterinária , Síndrome Definhante Multissistêmico de Suínos Desmamados/virologia , Animais , Infecções por Circoviridae/diagnóstico , Infecções por Circoviridae/virologia , Circovirus/genética , DNA Viral/química , DNA Viral/genética , Hibridização In Situ/veterinária , Linfonodos/virologia , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Síndrome Definhante Multissistêmico de Suínos Desmamados/diagnóstico , Sensibilidade e Especificidade , Suínos
19.
Traffic Inj Prev ; 20(sup2): S128-S132, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31800326

RESUMO

Objective: Studies of vehicle occupant motions in response to abrupt vehicle maneuvers have demonstrated movements that may result in changes in the level of protection for the occupant if a crash subsequently occurs. The previous studies have typically used a single vehicle. The current study assesses whether the patterns of occupant head movement are different across passenger vehicle types.Method: Data collection was conducted on a closed test track with the same driver for all trials. A passenger sedan, a minivan, and a pickup truck were equipped with inertial measurement units to quantify vehicle dynamics. Head location was tracked using Microsoft Kinect v2 sensor and a novel methodology that fits 3 D head scan data to the depth data acquired in the vehicle. Twelve men and women with a wide range of body size and age were recruited. The primary purpose of the study was obfuscated by telling the participants that the focus was on vehicle ride motion. Participants sat in the right front seat and wore the vehicle belt. The first event during the test track route was a hard brake (approximately 1 g) to a stop from 35 mph (56 kph). Within the space of approximately 5 min the participants also experienced two aggressive, right-going lane changes, a sharp right turn with simultaneous hard braking, and a second hard braking event. The vehicles were presented in random order for each participant. This paper presents comparison across vehicles of head motions in the braking and lane-change maneuvers.Results: Accelerations were similar across the vehicles for both braking and lane-change events. The means (standard deviations) of forward head-CG excursion in the first braking event were 162 (54), 112 (39), and 176 (46) mm for the minivan, passenger car, and truck, respectively. The forward head excursion in the passenger car was found to be significantly smaller than in the other two vehicles using a paired t-test (p < 0.01). Across vehicles, the mean excursion in the second braking exposure was smaller than in the first (p < 0.01). In the first lane change event, the mean (SD) inboard head excursions were 126 (51), 110 (49), and 140 (68) mm; the values were not significantly different across vehicles or in the second lane-change event. A detailed investigation did not reveal an explanation for the smaller head excursions in the passenger car.Discussion: This is the first quantitative occupant kinematics study to compare responses across vehicles. Although a significant difference was found between vehicles, the overall responses are similar to those observed in a previous study.Conclusions: The results confirm previous studies showing large variance in excursions across occupants. Further study is needed to understand the factors that affect responses across vehicles.


Assuntos
Acidentes de Trânsito/prevenção & controle , Cabeça , Veículos Automotores/estatística & dados numéricos , Aceleração , Adulto , Idoso , Fenômenos Biomecânicos , Tamanho Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
20.
Br J Pharmacol ; 153(4): 820-30, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18071297

RESUMO

BACKGROUND AND PURPOSE: Paracetamol, a major cause of acute liver failure (ALF) represents a significant clinical problem. Adrenoceptor stimulation or antagonism can modulate chemical-induced hepatotoxicity. We investigated the role of endogenous catecholamines and alpha(1)-adrenoceptors in the development of paracetamol- induced hepatotoxicity. EXPERIMENTAL APPROACH: Paracetamol (3.5 mmol kg(-1)) was administered to male CD-1 mice, with and without alpha(1)-adrenoceptor antagonists (prazosin, doxazosin, terazosin and tamsulosin; 35.7 micromol kg(-1)). Serum transaminases and hepatic glutathione (GSH) levels were assessed as markers of hepatic damage. Paracetamol bioactivation was assessed by covalent binding, hepatic and urinary conjugate formation and uridine glucuronosyltransferase activity. Plasma catecholamines levels and hepatic congestion were also analysed. KEY RESULTS: Plasma catecholamine levels were significantly elevated 5 h post paracetamol administration. Prazosin prevented hepatotoxicity when administered 1 h before a toxic paracetamol insult and importantly, when administered up to 1 h post paracetamol injection. Prazosin had no effect on paracetamol-induced depletion of hepatic GSH, paracetamol bioactivation or paracetamol-induced transcription of defence genes. Paracetamol toxicity is associated with marked accumulation of erythrocytes within hepatic sinusoids and prazosin completely prevented this accumulation. CONCLUSION AND IMPLICATIONS: Paracetamol-induced hepatocellular damage is associated with increased circulating catecholamines. alpha(1)-Adrenoceptor antagonists conferred complete protection from paracetamol -induced hepatotoxicity. Protection was associated with absence of hepatic erythrocyte accumulation. Increased catecholamine levels may contribute to the pathophysiology of paracetamol-induced hepatotoxicity by compromising hepatic perfusion. Protection against paracetamol toxicity by alpha(1) antagonists in mice has implications for therapeutic management of patients presenting with paracetamol overdose and ALF.


Assuntos
Antagonistas de Receptores Adrenérgicos alfa 1 , Antagonistas Adrenérgicos alfa/farmacologia , Hepatopatias/prevenção & controle , Fígado/efeitos dos fármacos , Prazosina/farmacologia , Acetaminofen/metabolismo , Antagonistas Adrenérgicos alfa/uso terapêutico , Animais , Catecolaminas/sangue , Doença Hepática Induzida por Substâncias e Drogas , Modelos Animais de Doenças , Doxazossina/farmacologia , Eritrócitos/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Glutamato-Cisteína Ligase/genética , Glutamato-Cisteína Ligase/metabolismo , Glutationa/metabolismo , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Fígado/irrigação sanguínea , Fígado/enzimologia , Fígado/metabolismo , Fígado/patologia , Circulação Hepática/efeitos dos fármacos , Hepatopatias/metabolismo , Hepatopatias/patologia , Hepatopatias/fisiopatologia , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Prazosina/análogos & derivados , Prazosina/uso terapêutico , Ligação Proteica , Receptores Adrenérgicos alfa 1/metabolismo , Sulfonamidas/farmacologia , Tansulosina , Fatores de Tempo , Transaminases/sangue
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