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2.
Public Health Action ; 11(3): 146-154, 2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34567991

RESUMO

BACKGROUND: WHO drug-resistant TB (DR-TB) treatment recommendations now emphasize all-oral regimens, recommending against certain injectable agents and deprioritizing others due to inferior safety and efficacy. Despite increasing focus on patient-centered care, we are not aware of systematic attempts to qualitatively document patients' perspectives on injectable agents. This may inform implementation of WHO guidelines, emphasizing the importance of consultation with affected communities. METHODS: Testimonies were provided by TB survivors who experienced hearing loss from treatment with injectable agents. Testimonies were submitted in writing in response to minimal, standardized, open-ended prompts. Participants provided a signed consent form (with options to participate anonymously or as a named co-author), and later gave input into the overall shape and recommendations of the article. RESULTS: Fourteen TB survivors in 12 countries contributed testimonies. The following common themes emerged: lack of access to appropriate testing, information, treatment, or a collaborative treatment environment; the power of supportive care and social environments; stigma and isolation from TB treatment itself and resultant disability; and inaccessibility of cochlear implants. CONCLUSIONS: Survivor testimonies indicate strong preferences for avoidance of injectable agents, supporting rapid implementation of revised WHO guidelines, as well as for quality and supportive care for both TB and disabilities.


CONTEXTE: Les recommandations de l'OMS pour le traitement de la TB pharmacorésistante (DR-TB) mettent désormais l'accent sur les schémas thérapeutiques entièrement par voie orale, préconisant de ne pas utiliser certains agents injectables et de ne plus donner la priorité à d'autres en raison d'une innocuité et d'une efficacité inférieures. Malgré l'attention accrue portée aux soins centrés sur le patient, nous ne connaissons aucune étude systématique ayant cherché à documenter de manière qualitative le point de vue des patients sur les agents injectables. Ce travail pourrait guider la mise en place des directives de l'OMS, en mettant l'accent sur l'importance de consulter les communautés concernées. MÉTHODES: Des personnes ayant survécu à une TB et ayant connu une perte d'audition due à un traitement par agents injectables ont apporté leurs témoignages. Les témoignages ont été soumis par écrit en réponse à des questions courtes, ouvertes et standardisées. Les participants ont signé un formulaire de consentement (avec possibilité de participer de manière anonyme ou en tant que coauteur nommé) et ont ensuite contribué au format général et aux recommandations de l'article. RÉSULTATS: Quatorze personnes ayant survécu à une TB provenant de 12 pays ont apporté leur témoignage. Les thématiques suivantes ont été fréquemment mentionnées : manque d'accès aux tests, informations et traitements appropriés ou à un environnement thérapeutique collaboratif ; importance des soins de soutien et de l'environnement social ; stigmatisation et isolement dus au traitement antituberculeux et handicaps qui en résultent ; et inaccessibilité aux implants cochléaires. CONCLUSIONS: Le témoignage des personnes ayant survécu à une TB indique qu'elles préfèrent nettement éviter les agents injectables, allant ainsi dans le sens d'une mise en place rapide des directives révisées de l'OMS, et qu'elles préfèrent des soins de qualité et de soutien pour la TB mais aussi pour les handicaps qui en résultent.

4.
Oncogene ; 37(4): 461-477, 2018 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-28967906

RESUMO

Recently, we reported that the histone methyltransferase, EZH2, controls leukocyte migration through interaction with the cytoskeleton remodeling effector, VAV, and direct methylation of the cytoskeletal regulatory protein, Talin. However, it is unclear whether this extranuclear, epigenetic-independent function of EZH2 has a profound impact on the initiation of cellular transformation and metastasis. Here, we show that EZH2 increases Talin1 methylation and cleavage, thereby enhancing adhesion turnover and promoting accelerated tumorigenesis. This transforming capacity is abolished by targeted disruption of EZH2 interaction with VAV. Furthermore, our studies demonstrate that EZH2 in the cytoplasm is closely associated with cancer stem cell properties, and that overexpression of EZH2, a mutant EZH2 lacking its nuclear localization signal (EZH2ΔNLS), or a methyl-mimicking Talin1 mutant substantially promotes JAK2-dependent STAT3 activation and cellular transformation. Taken together, our results suggest a critical role for the VAV interaction-dependent, extranuclear action of EZH2 in neoplastic transformation.


Assuntos
Transformação Celular Neoplásica/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias/patologia , Proteínas Proto-Oncogênicas c-vav/metabolismo , Animais , Adesão Celular/genética , Linhagem Celular Tumoral , Transformação Celular Neoplásica/patologia , Citoplasma/genética , Citoplasma/patologia , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Proteína Potenciadora do Homólogo 2 de Zeste/isolamento & purificação , Feminino , Técnicas de Silenciamento de Genes , Células HEK293 , Humanos , Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Células Jurkat , Metilação , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos NOD , Camundongos SCID , Mutagênese Sítio-Dirigida , Neoplasias/genética , Sinais de Localização Nuclear/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Talina/genética , Talina/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Clin Transl Sci ; 10(6): 496-502, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28675684

RESUMO

A translational need exists to understand and predict vancomycin-induced kidney toxicity. We describe: (i) a vancomycin high-performance liquid chromatography (HPLC) method for rat plasma and kidney tissue homogenate; (ii) a rat pharmacokinetic (PK) study to demonstrate utility; and (iii) a catheter retention study to enable future preclinical studies. Rat plasma and pup kidney tissue homogenate were analyzed via HPLC for vancomycin concentrations ranging from 3-75 and 15.1-75.5 µg/mL, respectively, using a Kinetex Biphenyl column and gradient elution of water with 0.1% formic acid: acetonitrile (70:30 v/v). Sprague-Dawley rats (n = 10) receiving 150 mg/kg of vancomycin intraperitoneally had plasma sampled for PK. Finally, a catheter retention study was performed on polyurethane catheters to assess adsorption. Precision was <6.1% for all intra-assay and interassay HPLC measurements, with >96.3% analyte recovery. A two-compartment model fit the data well, facilitating PK exposure estimates. Finally, vancomycin was heterogeneously retained by polyurethane catheters.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Testes de Toxicidade , Vancomicina/farmacocinética , Vancomicina/toxicidade , Animais , Teorema de Bayes , Bioensaio , Cateterismo , Rim/metabolismo , Masculino , Ratos Sprague-Dawley , Extratos de Tecidos , Vancomicina/sangue
6.
J Laryngol Otol ; 131(4): 350-356, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28124628

RESUMO

OBJECTIVES: To validate the ovine model of profound oropharyngeal dysphagia and compare swallowing outcomes of laryngotracheal separation with those of total laryngectomy. METHODS: Under real-time fluoroscopy, swallowing trials were conducted using the head and neck of two Dorper cross ewes and one human cadaver, secured in lateral fluoroscopic orientation. Barium trials were administered at baseline, pre- and post-laryngohyoid suspension, following laryngotracheal separation, and following laryngectomy in the ovine model. RESULTS: Mean pre-intervention Penetration Aspiration Scale and National Institutes of Health Swallow Safety Scale scores were 8 ± 0 and 6 ± 0 respectively in sheep and human cadavers, with 100 per cent intra- and inter-species reproducibility. These scores improved to 1 ± 0 and 2 ± 0 post-laryngohyoid suspension (p < 0.01). Aerodigestive tract residue was 18.6 ± 2.4 ml at baseline, 15.4 ± 3.8 ml after laryngotracheal separation and 3.0 ± 0.7 ml after total laryngectomy (p < 0.001). CONCLUSION: The ovine model displayed perfect intra- and inter- species reliability for the Penetration Aspiration Scale and Swallow Safety Scale. Less aerodigestive tract residue after narrow-field laryngectomy suggests that swallowing outcomes after total laryngectomy are superior to those after laryngotracheal separation.


Assuntos
Transtornos de Deglutição/cirurgia , Deglutição/fisiologia , Laringectomia/métodos , Laringoscopia/métodos , Animais , Cadáver , Transtornos de Deglutição/fisiopatologia , Modelos Animais de Doenças , Feminino , Humanos , Laringe/cirurgia , Período Pós-Operatório , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Ovinos , Traqueia/cirurgia , Resultado do Tratamento
7.
Clin Exp Allergy ; 44(11): 1347-60, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25255717

RESUMO

BACKGROUND: Infiltration of fibrocytes (FC) in the airway smooth muscle is a feature of asthma, but the pathological significance is unknown. OBJECTIVE: We sought to explore whether FC modulate the phenotype of airway smooth muscle cells (ASMC) in asthmatic vs. control subjects. METHODS: Fibrocytes were isolated from CD14+ monocytes from asthmatic and normal subjects. Proliferation of ASMC of asthmatic or normal subjects was analysed by (3) H-thymidine incorporation, cell number counting and Ki-67 expression after treatment of ASMC with FC-conditioned medium (FCCM) or co-culture with FC. ASMC-associated cytokines/chemokines implicated in asthma (TGF-ß1, eotaxin, IL-6 and IL-8) were measured in co-culture or transwell culture of ASMC + FC by ELISA. Immunofluorescence staining was performed to localize these cytokines in ASMC. Cytokine secretion was measured in the transwell culture of ASMC + FC, where NF-κB-p65 or ERK1/2 in ASMC was silenced by siRNA. Contractile phenotype of ASMC in transwell culture was assessed by immunoblotting of α-smooth muscle actin (α-SMA) and myosin light chain kinase (MLCK). RESULTS: Fibrocytes did not affect ASMC proliferation and expression of TGF-ß1, eotaxin, α-SMA and MLCK; however, ASMC production of IL-8 and IL-6 was increased in the co-culture and transwell culture by FC. ASMC treated with FCCM were immunopositive for IL-8/IL-6 and produced more IL-8/IL-6. Furthermore, siRNA silencing of NF-κB-p65 or ERK1/2 in transwell cultures of asthmatic ASMC with normal subject FC decreased IL-8 and IL-6 production. CONCLUSIONS AND CLINICAL RELEVANCE: Fibrocytes promoted IL-8 and IL-6 production by ASMC, demonstrating a proinflammatory role for FC and a possible mechanism of the inflammatory phenotype in asthma.


Assuntos
Asma/metabolismo , Asma/patologia , Monócitos/metabolismo , Miócitos de Músculo Liso/metabolismo , Fenótipo , Actinas/metabolismo , Adulto , Asma/diagnóstico , Asma/imunologia , Estudos de Casos e Controles , Comunicação Celular , Diferenciação Celular , Células Cultivadas , Técnicas de Cocultura , Colágeno Tipo I/metabolismo , Feminino , Humanos , Interleucina-6/biossíntese , Interleucina-8/biossíntese , Masculino , Pessoa de Meia-Idade , Monócitos/citologia , Quinase de Cadeia Leve de Miosina/metabolismo , Transdução de Sinais
8.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 2): o106, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24764838

RESUMO

In the title compound, C22H15N3O, the dihedral angle between the two indole units is 33.72 (3)°. The mol-ecular structure features a weak intra-molecular C-H⋯N inter-action. In the crystal, weak C-H⋯O and C-H⋯π inter-actions, forming a two-dimensional network parallel to the bc plane.

9.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 2): o197, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24764907

RESUMO

In the title compound C20H13N5, the dihedral angle between the carbazole ring system (r.m.s. deviation = 0.027 Å) and the pendant benzene ring is 55.08 (6)°. One of the azide N atoms is disordered over two positions in a 0.65 (2):0.35 (2) ratio. In the crystal, aromatic π-π stacking is observed [minimum centroid-centroid separation = 3.6499 (13) Å] as well as inversion-dimers connected by pairs of weak C-H⋯π inter-actions.

10.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 10): o2796, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-22058824

RESUMO

In the title compound, C(20)H(14)N(2), the carbazole ring system is essentially planar (r.m.s. deviation = 0.187 Å) and is inclined at an angle of 54.33 (4) ° with respect to the benzene ring. The crystal packing is stabilized by weak C-H⋯N and C-H⋯π inter-actions.

11.
Ann Oncol ; 22(1): 68-73, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20647220

RESUMO

BACKGROUND: although trastuzumab has improved the prognosis for HER-2-positive breast cancer patients, not all HER-2-positive breast tumours respond to trastuzumab treatment and those that initially respond frequently develop resistance. Insulin-like growth factor-1 receptor (IGF1R) signalling has been previously implicated in trastuzumab resistance. We tested IGF1R inhibition to determine if dual targeting of HER-2 and IGF1R improves response in cell line models of acquired trastuzumab resistance. MATERIALS AND METHODS: HER-2, IGF1R, phospho-HER-2, and phospho-IGF1R levels were measured by enzyme-linked immunosorbent assays in parental and trastuzumab-resistant SKBR3 and BT474 cells. IGF1R signalling was targeted in these cells using both small interfering RNA (siRNA) and the tyrosine kinase inhibitor, NVP-AEW541. RESULTS: IGF1R levels were significantly increased in the trastuzumab-resistant model, SKBR3/Tr, compared with the parental SKBR3 cell line. In both the SKBR3/Tr and BT474/Tr cell lines, inhibition of IGF1R expression with siRNA or inhibition of tyrosine kinase activity by NVP-AEW541 significantly increased response to trastuzumab. The dual targeting approach also improved response in the parental SKBR3 cells but not in the BT474 parental cells. CONCLUSIONS: our results confirm that IGF1R inhibition improves response to trastuzumab in HER-2-positive breast cancer cells and suggest that dual targeting of IGF1R and HER-2 may improve response in HER-2-positive tumours.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/terapia , Receptor ErbB-2/antagonistas & inibidores , Receptor IGF Tipo 1/antagonistas & inibidores , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais Humanizados , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/enzimologia , Neoplasias da Mama/genética , Processos de Crescimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Terapia Combinada , Resistencia a Medicamentos Antineoplásicos , Sinergismo Farmacológico , Feminino , Humanos , Inibidores de Proteínas Quinases/administração & dosagem , Pirimidinas/administração & dosagem , Pirróis/administração & dosagem , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/genética , Receptor ErbB-2/biossíntese , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo , Transfecção , Trastuzumab
12.
Br J Cancer ; 98(6): 1076-84, 2008 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-18334972

RESUMO

In this study, we explore the therapeutic potential of lapatinib a selective inhibitor of both the EGFR and HER2 tyrosine kinases for the treatment of endometrial cancer. The effect of lapatinib on tumour cell growth and receptor activation was studied in a panel of human endometrial cancer cell lines. Candidate molecular markers predicting sensitivity were assessed by baseline gene expression profiling, ELISA, and western blot analyses. Multiple drug effect/combination index (CI) isobologram analysis was used to study the interactions between chemotherapeutic drugs and lapatinib. Concentration-dependent anti-proliferative effects of lapatinib were seen in all endometrial cancer cell lines tested, but varied significantly between individual cell lines (IC(50) range: 0.052-10.9 micromol). HER2 overexpression or increased expression of EGFR was significantly associated with in vitro sensitivity (P=0.024 or 0.011, respectively). Lapatinib exerts growth inhibition in a PTEN-independent manner. Sensitive cell lines also exhibited increased expression of EGFR ligands or HER3. In contrast, lapatinib-resistant cell lines exhibited high androgen receptor (AR) levels or epithelial-to-mesenchymal transition (post-EMT) features. In endometrial cancer cells, at a wide range of clinically achievable drug concentrations, additive and synergistic interactions were observed for lapatinib plus carboplatin, paclitaxel, docetaxel, and doxorubicin. These observations provide a clear biologic rational to test lapatinib as a single agent or in combination with chemotherapy in endometrial cancer with HER2 overexpression. Expression of EGFR, its ligands, HER3, AR, and post-EMT markers warrant further evaluation to help define patients with HER2-nonoverexpressing endometrial cancer most likely to benefit from lapatinib.


Assuntos
Neoplasias do Endométrio/tratamento farmacológico , Receptores ErbB/antagonistas & inibidores , Inibidores de Proteínas Quinases/uso terapêutico , Quinazolinas/uso terapêutico , Receptor ErbB-2/antagonistas & inibidores , Protocolos de Quimioterapia Combinada Antineoplásica , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Receptores ErbB/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Humanos , Lapatinib , Proteína Oncogênica v-akt/metabolismo , Quinazolinas/administração & dosagem , Receptor ErbB-2/metabolismo , Transdução de Sinais/efeitos dos fármacos
13.
Int J Pharm ; 310(1-2): 46-52, 2006 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-16439074

RESUMO

Oral administration of mucoadhesive tablets containing erythropoietin (EPO) and an absorption enhancer Labrasol was studied in rats and dogs. Mucoadhesive tablets were prepared using Sylysia 550 holding the absorption enhancer and Carbopol 974P as a mucoadhesive agent. Mucoadhesive tablets were covered with a water-insoluble backing layer made of cellulose acetate and a pH-sensitive covering layer made of Eudragit L/Eudragit S. Tablet was administered into the rat jejunum at EPO dose of 100 IU/kg and serum samples were collected for 6h. Serum EPO level was analysed with a standard ELISA procedure. After administration, rats showed a maximum serum EPO level of C(max) 70.6 +/- 8.9 mIU/ml. Oral administration of a single tablet containing 100 IU/kg EPO to beagle dogs showed a C(max) of 24.6 +/- 4.1. When EPO dose was increased to 500 IU/kg and the number of tablets was also increased to 5, the C(max) was 54.8 +/- 9.0 mIU/ml. However, when EPO, 100 IU/kg dose was divided into five tablets, the C(max) was 15.5 +/- 1.8 mIU/ml. In the absence of absorption enhancer, the C(max) was 35.8 +/- 3.8 with 500 IU/kg dose distributed among five tablets. Pharmacodynamic studies were carried out following oral administration of mucoadhesive tablets for 6 consecutive days at an EPO dose of 500 IU/kg. Whole blood samples were collected and percent circulating reticulocytes were counted using Miller technique. The increase in percent circulating reticulocytes was found to be 1.7% on day 8 following oral administration. As a control study, EPO was administered by i.v. route at a dose of 300 IU/kg for 3 consecutive days and the percent circulating reticulocytes were counted. Mucoadhesive tablets showed promising results as an oral drug delivery system for protein therapeutics.


Assuntos
Eritropoetina/administração & dosagem , Eritropoetina/farmacocinética , Absorção Intestinal , Acrilatos/química , Adesividade , Administração Oral , Animais , Química Farmacêutica , Cães , Relação Dose-Resposta a Droga , Eritropoetina/química , Glicerídeos , Absorção Intestinal/efeitos dos fármacos , Masculino , Mucosa/química , Compostos Orgânicos/farmacologia , Ratos , Ratos Sprague-Dawley , Contagem de Reticulócitos , Comprimidos com Revestimento Entérico
14.
J Control Release ; 111(1-2): 19-26, 2006 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-16377018

RESUMO

The absorption of erythropoietin (EPO) from rat small intestine was studied using gastro-intestinal patches (GI-PS) in the presence of absorption enhancers. Surfactants such as a saturated polyglycolysed C8-C18 glyceride (Gelucire 44/14), PEG-8 capryl/caprylic acid glycerides (Labrasol), and polyoxyethylene hydrogenated castor oil derivative (HCO-60) were used as absorption enhancers at 143, 94 and 20 mg/kg, respectively. The absorption of EPO was studied by measuring serum EPO levels by an ELISA method after small intestinal administration of EPO-GI-PS preparation in rats at the EPO dose level of 100 IU/kg. Labrasol showed the highest absorption enhancing effect after intrajejunum administration with maximum serum EPO level of 84.1+/-11.4 mIU/ml while Gelucire 44/14 and HCO-60 showed 43.5+/-9.8 and 26.5+/-2.3 mIU/ml, respectively. The appropriate site for EPO absorption was also investigated. Jejunum was found to be the most efficient absorption site for the absorption of EPO from GI-PS. Using Labrasol as the absorption enhancer and jejunum as the absorption site, the effect of EPO dose on EPO absorption was studied by increasing the EPO dose from 50, to 100, 300 and 600 IU/kg. It was found that 100 IU/kg was the optimum dose with a serum EPO level of 84.1+/-11.4 mIU/ml while escalating doses showed decreases in serum EPO levels 48.3+/-5.6 for 300 IU/kg and 50.6+/-10.3 mIU/ml for 600 IU/kg. The percent bioavailability (BA) of EPO-GI-PS with Labrasol as absorption enhancer was 7.9 at 50 IU/kg, 12.1 at 100 IU/kg, 3.2 at 300 IU/kg and 1.2 at 600 IU/kg. Histological studies showed no adverse effect at the site of administration.


Assuntos
Portadores de Fármacos/química , Eritropoetina/farmacocinética , Trato Gastrointestinal/metabolismo , Administração Oral , Algoritmos , Animais , Área Sob a Curva , Óleo de Rícino/análogos & derivados , Óleo de Rícino/química , Sistemas de Liberação de Medicamentos , Eritropoetina/administração & dosagem , Eritropoetina/química , Glicerídeos , Absorção Intestinal , Jejuno/metabolismo , Masculino , Taxa de Depuração Metabólica , Compostos Orgânicos/química , Polietilenoglicóis/química , Ratos , Ratos Wistar
15.
J Pharm Pharm Sci ; 8(1): 39-46, 2005 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-15946596

RESUMO

PURPOSE: Asparagus racemosus Wild root has been used traditionally in Ayurveda for the treatment of diarrhoea and dysentery. However, the claims of Ayurveda need to be validated by a suitable experimental model. Therefore, the present study was undertaken to evaluate the effect of ethanol and aqueous extracts of Asparagus racemosus for its antidiarrhoeal potential against several experimental models of diarrhoea in Albino Wistar rats. METHODS: The antidiarrhoeal activity of ethanol and aqueous extracts of Asparagus racemosus root was evaluated using castor oil-induced diarrhoea model in rats. Further, we evaluated the effect of ethanol and aqueous extracts on gastrointestinal tract motility after charcoal meal administration and PGE2 induced intestinal fluid accumulation (enteropooling). Loperamide was used as positive control. RESULTS: The plant extracts showed significant (P < 0.05) inhibitor activity against castor oil induced diarrhoea and PGE2 induced enteropooling in rats when tested at 200 mg/kg. Both extracts also showed significant (P < 0.001) reduction in gastrointestinal motility in charcoal meal test in rats. CONCLUSION: The results point out the possible anti-diarrhoeal effect of the plant extracts and substantiate the use of this herbal remedy as a non-specific treatment for diarrhoea in folk medicine.


Assuntos
Antidiarreicos/uso terapêutico , Asparagus , Diarreia/tratamento farmacológico , Fitoterapia/métodos , Raízes de Plantas , Animais , Diarreia/fisiopatologia , Feminino , Masculino , Extratos Vegetais/uso terapêutico , Ratos , Ratos Wistar
16.
Proc Natl Acad Sci U S A ; 101(52): 18087-92, 2004 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-15601778

RESUMO

Osteoarthritis is a degenerative joint disease characterized by a progressive loss of articular cartilage components, mainly proteoglycans (PGs), leading to destruction of the tissue. We investigate a therapeutic strategy based on stimulation of PG synthesis by gene transfer of the glycosaminoglycan (GAG)-synthesizing enzyme, beta1,3-glucuronosyltransferase-I (GlcAT-I) to promote cartilage repair. We previously reported that IL-1beta down-regulated the expression and activity of GlcAT-I in primary rat chondrocytes. Here, by using antisense oligonucleotides, we demonstrate that GlcAT-I inhibition impaired PG synthesis and deposition in articular cartilage explants, emphasizing the crucial role of this enzyme in PG anabolism. Thus, primary chondrocytes and cartilage explants were engineered by lipid-mediated gene delivery to efficiently overexpress a human GlcAT-I cDNA. Interestingly, GlcAT-I overexpression significantly enhanced GAG synthesis and deposition as evidenced by (35)S-sulfate incorporation, histology, estimation of GAG content, and fluorophore-assisted carbohydrate electrophoresis analysis. Metabolic labeling and Western blot analyses further suggested that GlcAT-I expression led to an increase in the abundance rather than in the length of GAG chains. Importantly, GlcAT-I delivery was able to overcome IL-1beta-induced PG depletion and maintain the anabolic activity of chondrocytes. Moreover, GlcAT-I also restored PG synthesis to a normal level in cartilage explants previously depleted from endogenous PGs by IL-1beta-treatment. In concert, our investigations strongly indicated that GlcAT-I was able to control and reverse articular cartilage defects in terms of PG anabolism and GAG content associated with IL-1beta. This study provides a basis for a gene therapy approach to promote cartilage repair in degenerative joint diseases.


Assuntos
Cartilagem/patologia , Técnicas de Transferência de Genes , Glucuronosiltransferase/genética , Osteoartrite/terapia , Proteoglicanas/metabolismo , Animais , Western Blotting , Metabolismo dos Carboidratos , Cartilagem/metabolismo , Cartilagem Articular/patologia , Condrócitos/metabolismo , DNA Complementar/metabolismo , Regulação para Baixo , Vetores Genéticos , Humanos , Imuno-Histoquímica , Interleucina-1/metabolismo , Metabolismo dos Lipídeos , Oligonucleotídeos Antissenso/farmacologia , Ratos , Fatores de Tempo , Transfecção , Cicatrização
17.
Br J Ophthalmol ; 88(12): 1521-6, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15548804

RESUMO

BACKGROUND/AIM: Retinoblastoma is the commonest primary intraocular tumour in children. Chemotherapy now plays a big part in the treatment of these tumours. There is not much information about the role of the multidrug resistance proteins (MDR)-P-glycoprotein (P-gp) and vault protein lung resistance protein (LRP)-in retinoblastoma. The authors investigated the expression of P-gp and LRP in retinoblastoma and correlated them clinicopathologically. METHODS: Among 60 retinoblastomas, 40 tumours were not subjected to preoperative or postoperative chemotherapy and 20 tumours were subjected to postoperative chemotherapy. In this cohort 27 tumours had no invasion and 33 tumours had invasion of choroid, optic nerve, and orbit. P-gp and LRP expression were studied by immunohistochemistry. Immunoanalysis was done semiquantitatively. RESULTS: Among the 60 tumours P-gp was expressed in 23 (38%) tumours and LRP was expressed in 35 (58%). P-gp was expressed in 11/27 (40%) tumours with no invasion and in 12/33 (36%) tumours with invasion. LRP was expressed in 15/27 (55%) tumours with no invasion and in 20/33 (60%) tumours with invasion. Both P-gp and LRP were negative in three tumours with invasion, which had later developed bone marrow metastasis. There was no correlation between P-gp and LRP expression with invasion, differentiation and laterality of the tumours and response to treatment. CONCLUSION: Retinoblastoma expresses P-gp and LRP intrinsically before chemotherapy and none of these proteins predicted the response to chemotherapy. Thus, further studies are needed to understand the significance of the expression of the P-gp and LRP proteins in retinoblastoma.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/análise , Proteínas de Neoplasias/análise , Neoplasias da Retina/tratamento farmacológico , Retinoblastoma/tratamento farmacológico , Neoplasias da Medula Óssea/secundário , Criança , Pré-Escolar , Resistência a Múltiplos Medicamentos , Feminino , Humanos , Imuno-Histoquímica/métodos , Lactente , Masculino , Invasividade Neoplásica , Neoplasias da Retina/química , Neoplasias da Retina/patologia , Retinoblastoma/química , Retinoblastoma/patologia , Resultado do Tratamento , Partículas de Ribonucleoproteínas em Forma de Abóbada
18.
Am J Physiol Lung Cell Mol Physiol ; 287(6): L1342-7, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15333293

RESUMO

Administration of bleomycin (BM) produces inflammation and fibrosis of the lung in humans and experimental animals. The molecular defects by which BM induces these pathological effects have not been studied in detail. We studied the expression of Smad family proteins, key molecules involved in mediating transforming growth factor (TGF)-beta signaling from the cell membrane to the nucleus, during the early and late phases of BM-induced fibrogenesis. Pulmonary fibrosis was induced in male Sprague-Dawley rats by a single intratracheal injection (1.5 units) of BM. Control rats received saline. Rats were killed at 3, 5, 7, 14, and 28 days after BM, cytosolic and nuclear proteins were extracted and isolated from lung tissues, and Smad proteins were probed with specific antibodies. In BM-exposed lung tissue, compared with control, Smad3 decreased persistently in the cytosol and increased transiently in the nucleus. There was a persistent increase in phosphorylation and nuclear accumulation of Smad2/3. Smad4 was increased transiently in both the cytosol and nucleus. A significant and progressive decrease in the expression of Smad7, the endogenous inhibitor of TGF-beta/Smad signaling, was observed after BM instillation. Collectively, our results indicate that an imbalance between agonistic Smads2-4 and antagonistic Smad7 may result in the unchecked activation of an autocrine TGF-beta loop, which contributes to the pathogenesis of BM-induced pulmonary fibrosis.


Assuntos
Bleomicina/toxicidade , Proteínas de Ligação a DNA/genética , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/patologia , Transdução de Sinais/genética , Transativadores/genética , Animais , Núcleo Celular/metabolismo , Citosol/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Proteínas Smad , Proteína Smad3 , Proteína Smad7
19.
Surgery ; 130(5): 834-43, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11685193

RESUMO

BACKGROUND: The neural cell adhesion molecule (NCAM) has numerous isoforms resulting from alternative splicing of mRNA. The 3 major isoforms found in adult tissue are (1) a 120-kDa protein that is linked to the plasma membrane by glycosylphosphatidylinositol; (2) a 140-kDa form that has a transmembrane component and a cytoplasmic tail with unknown function; and (3) a 180-kDa isoform that has an intracellular protein that binds the cytoskeleton. NCAM is capable of homotypic binding and therefore plays a role in cell-cell adhesion for cells expressing the 180-kDa isoform by anchoring groups of cells into epithelial sheets. NCAM-180 is the isoform found in colonocytes, and loss of expression is associated with clinically aggressive colon cancers. METHODS: Western blotting and reverse transcriptase-polymerase chain reaction were used to screen commercially available cell lines for NCAM-180 expression. For cell-line pairs with differential NCAM-180 expression, exon analysis was performed with reverse transcriptase-polymerase chain reaction to determine where the molecule was spliced, culminating in failed expression. These results were confirmed with exon analysis in colon cancers harvested at the time of laparotomy. RESULTS: Analysis of a SW480 cell line (derived from a patient's primary colon cancer lesion) revealed NCAM-180 expression, whereas no expression was found in the SW620 cell line (derived from a metastatic lesion from the same patient). Exon analysis of NCAM mRNA transcripts from SW620 revealed that the transcripts were truncated after exon 12. This region correlates to an area between 2 fibronectin-III domains on the NCAM protein. CONCLUSIONS: The most common site for NCAM alternative splicing is between the 2 fibronectin-III domains corresponding to the border between exons 12 and 13 of the NCAM gene. Loss of NCAM-180 expression in aggressive colon carcinoma results from a splice defect in the same area, which may result in defective intracellular adhesion between colonocytes.


Assuntos
Processamento Alternativo , Neoplasias do Colo/genética , Moléculas de Adesão de Célula Nervosa/genética , Adesão Celular , Neoplasias do Colo/metabolismo , Fibronectinas/genética , Humanos , Receptores de Hialuronatos/genética , Imuno-Histoquímica , Moléculas de Adesão de Célula Nervosa/análise , Moléculas de Adesão de Célula Nervosa/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
20.
Pharmazie ; 56(3): 217-9, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11265586

RESUMO

The study was an attempt to develop an alternative buccal delivery system for insulin. Insulin bearing nanoparticles were prepared by the emulsion internal phase evaporation method. The effect of some formulation variables viz., polymer/drug ratio and emulsifier concentration was studied on particle size and entrapment efficiency. Nanoparticles were pelleted to impart three-dimensional structural conformity and coherence thereby facilitating buccal application. Solid lateral and horizontal sedimentaton in the pellet can be avoided by nanoparticulation and ensuring uniform drug distribution throughout the pellet. The in vitro studies of the pellets included bioadhesion and drug release profile. In vivo studies were performed on diabetic rats. A significant hypoglycemic response was observed after 7 h, without any detectable fluctuation in blood glucose profile and risk of hypoglycemia.


Assuntos
Adesivos/química , Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Resinas Acrílicas , Animais , Materiais Biocompatíveis , Diabetes Mellitus Experimental/tratamento farmacológico , Emulsões , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Técnicas In Vitro , Insulina/química , Insulina/farmacologia , Mucosa Intestinal/metabolismo , Microesferas , Tamanho da Partícula , Polímeros , Coelhos , Ratos
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