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1.
J Biol Inorg Chem ; 28(8): 751-766, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37955736

RESUMO

Three new dinuclear gold(I) complexes (1-3) containing a carbene (1,3-Bis(2,6-di-isopropylphenyl)imidazol-2-ylidene (IPr)) and diphosphane ligands [bis(1,2-diphenylphosphano)ethane (Dppe), bis(1,3-diphenylphosphano)propane (Dppp) and bis[2-(dicyclohexylphosphano)ethyl]amine (DCyPA)], were synthesized and characterized by elemental analysis and, ESI-MS, mid FT-IR and NMR spectroscopic methods. The structures of complexes 2 and 3 were determined by X-ray crystallography, which revealed that the complexes are dinuclear having gold(I) ions linearly coordinated. The anticancer activities of the complexes (1-3) were evaluated in lung (A549), breast (MC-F7), prostate (PC-3), osteosarcoma (MG-63) and ovarian (A2780 and A2780cis) cancer models. Growth inhibition by the new complexes was higher than cisplatin in all cell lines tested. The mechanism of action of complex 3 was investigated in A549 cells using 2-dimensional (2D) models and 3D-multicellular tumor spheroids. Treatment of A549 cells with complex 3 caused: the induction of apoptosis and the generation of reactive oxygen species; the cell cycle arrest in the G0/G1 phase; the inhibition of both the proteasome and the NF-kB activity; the down-regulation of lung cancer stem cell markers (NOTCH1, CD133, ALDH1 and CD44). Complex 3 was more active than cisplatin also in 3D models of A549 lung cancer cells.


Assuntos
Antineoplásicos , Complexos de Coordenação , Neoplasias Pulmonares , Neoplasias Ovarianas , Feminino , Masculino , Humanos , Linhagem Celular Tumoral , Neoplasias Pulmonares/tratamento farmacológico , Cisplatino/farmacologia , Complexo de Endopeptidases do Proteassoma/farmacologia , Ouro/farmacologia , Ouro/química , Antineoplásicos/farmacologia , Antineoplásicos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Pulmão , Células-Tronco , Ligantes , Proliferação de Células
2.
ACS Omega ; 8(29): 26437-26443, 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37521606

RESUMO

Novel N-aryl-functionalized PNP ligands (1-4) bearing m-alkyloxy/-silyloxy substituents were prepared and evaluated for chromium-catalyzed ethylene oligomerization using MMAO-3A as an activator. The selected Cr/PNP system under optimized condition exhibited high 1-octene-selective (up to 70 wt %) ethylene tetramerization at a remarkable rate (over 3000 kg gCr-1 h-1). More importantly, the undesirable polyethylene selectivity was restricted to a minimum level of ∼1-2 wt % for pre-catalysts derived with ligands 1 and 2. Employing chlorobenzene as a reaction medium yielded best productivity in conjunction to the total α-olefin (1-C6 + 1-C8) selectivity (∼88 wt %). N-aryl PNP ligands (3 and 4) incorporating m-silyloxy substituents in the phenyl ring exhibited relatively poorer tetramerization performance while yielding higher PE fraction as compared to their m-alkyloxy derivatives. A detailed molecular structure of the best-performing pre-catalyst 1-Cr was established by single-crystal X-ray diffraction analysis. The stability of 1/Cr-based catalyst system was investigated for a reaction time of up to 2 h under optimized condition.

3.
Med Oncol ; 40(7): 192, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37261532

RESUMO

Immune checkpoint inhibitors (ICIs) ± chemotherapy is the standard treatment for driver mutation-negative non-small cell lung cancer (NSCLC). However, accessibility to ICIs in LMICs is limited due to high cost, and platinum-based chemotherapy remains the mainstay of treatment. Metformin has anticancer properties, and studies suggest synergism between metformin and pemetrexed. Based on preclinical evidence, this combination may be more beneficial for STK11-mutated NSCLC, a subgroup, inherently resistant to ICIs. In this Simon two-stage, single-arm phase 2 trial, we investigated metformin with pemetrexed-carboplatin (PC) in patients with treatment-naive stage IV non-squamous NSCLC. The primary outcome was 6-month progression-free survival (PFS) rate. Secondary outcomes were safety, overall survival (OS), overall response rate (ORR), proportion of STK11 mutation, and effect of STK11 mutation on 6-month PFS rate. The study was terminated for futility after interim analysis. The median follow-up was 34.1 months. The 6-month PFS rate was 28% (95% CI 12.4-0.46). The median PFS and OS were 4.5 (95% CI 2.2-6.1) and 7.4 months (95% CI 5.3-15.3), respectively. The ORR was 72%. Gastrointestinal toxicities were the most common. No grade 4/5 toxicities were reported. Targeted sequencing was possible in nine cases. Two patients had STK11 mutation and a poor outcome (PFS < 12 weeks). We could not demonstrate the benefit of metformin with CP in terms of improvement in 6-month PFS rate; however, the combination was safe (CTRI/2019/02/017815).


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Metformina , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Pemetrexede , Carboplatina , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Metformina/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
4.
ACS Omega ; 7(19): 16333-16340, 2022 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35601288

RESUMO

Tetramerization of ethylene by chromium catalysts stabilized with functionalized N-aryl phosphineamine ligands C6H4(m-CF3)N(PPh2)2 (1), C6H4(p-CF3)N(PPh2)2 (2), C6H4(o-CF3)N=PPh2-PPh2 (3), and C6H3(3,5-bis(CF3))N(PPh2)2 (4) was evaluated. The parameter optimization includes temperature, co-catalyst, and solvent. Upon activation with MMAO-3A, the new catalyst system especially with m-functional PNP ligand (1) exhibited high 1-octene selectivity and productivity while giving minimum undesirable polyethylene and C10 + olefin by-products. Using PhCl as a solvent at 75 °C led to a remarkable α-olefin (1-C6 + 1-C8) selectivity (>90 wt %) at a reaction rate of 2000 kg·gCr -1·h-1. Under identical conditions, analogous PNP ligands bearing -CH3, -Et, and -Cl functional moieties at the meta position of the N-phenyl ring displayed significantly lower reactivity. The catalyst with p-functional ligand (2) exhibited lower activity and comparable selectivities, while the Cr/PPN (with ligand 3) system gave no noticeable reactivity. The molecular structure of the precatalyst (1-Cr), exhibiting a monomeric structural feature, was elucidated with the aid of single-crystal X-ray diffraction study.

5.
Anim Biotechnol ; 33(1): 128-140, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32573336

RESUMO

In vitro and in vivo studies were conducted to examine the effect of silkworm pupae oil on methane (CH4) emission and methanogens diversity. Five graded levels (2, 4, 6, 8 and 10%) of silkworm pupae oil were tested in vitro. Eighteen Mandya adult sheep were divided into three groups. All the animals were fed on similar basal diet except the oil supplementation in test groups. Oil level for supplementation was decided on the basis of in vitro study. In vitro study indicated a reduction of 22% in CH4 production with 2% oil supplementation. Animals in test groups were supplemented with oil (2%) either daily (CON) or intermittently (INT) on every alternate week for all the seven days. A significant reduction of 17-20% in enteric CH4 emission (g/d) was achieved due to oil supplementation in sheep. However, No variation was established between test groups CON and INT. In present study, Methanobrevibacter was major genus contributed ∼90% of the total rumen methanogens; whilst Methanobrevibacter gottschalkii was the most abundant methanogens species. Abundance of Methanobrevibacter ruminantium was affected with the oil supplementation. It can be concluded that the silkworm pupae oil at 2% can decrease CH4 emission by 15-20%.


Assuntos
Bombyx , Metano , Animais , Dieta , Suplementos Nutricionais , Fermentação , Metano/metabolismo , Pupa , Rúmen/metabolismo , Ovinos
6.
AJNR Am J Neuroradiol ; 42(11): 2077-2085, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34620587

RESUMO

BACKGROUND AND PURPOSE: Neuroimaging has an important role in detecting CNS involvement in children with systemic or CNS isolated hemophagocytic lymphohistiocytosis. We characterized a cohort of pediatric patients with CNS hemophagocytic lymphohistiocytosis focusing on neuroradiologic features and assessed whether distinct MR imaging patterns and genotype correlations can be recognized. MATERIALS AND METHODS: We retrospectively enrolled consecutive pediatric patients diagnosed with hemophagocytic lymphohistiocytosis with CNS involvement treated at 2 pediatric neurology centers between 2010 and 2018. Clinical and MR imaging data were analyzed. RESULTS: Fifty-seven children (40 primary, 70%) with a median age of 36 months (interquartile range, 5.5-80.8 months) were included. One hundred twenty-three MR imaging studies were assessed, and 2 broad imaging patterns were identified. Pattern 1 (significant parenchymal disease, 32/57, 56%) was seen in older children (P = .004) with worse clinical profiles. It had 3 onset subpatterns: multifocal white matter lesions (21/32, 66%), brainstem predominant disease (5, 15%), and cerebellitis (6, 19%). All patients with the brainstem pattern failed to meet the radiologic criteria for chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids. An attenuated imaging phenotype (pattern 2) was seen in 25 patients (44%, 30 studies) and was associated with younger age. CONCLUSIONS: Distinct MR imaging patterns correlating with clinical phenotypes and possible genetic underpinnings were recognized in this cohort of pediatric CNS hemophagocytic lymphohistiocytosis. Disruptive mutations and missense mutations with absent protein expression correlate with a younger onset age. Children with brainstem and cerebellitis patterns and a negative etiologic work-up require directed assessment for CNS hemophagocytic lymphohistiocytosis.


Assuntos
Encefalopatias , Linfo-Histiocitose Hemofagocítica , Criança , Pré-Escolar , Humanos , Lactente , Linfo-Histiocitose Hemofagocítica/diagnóstico por imagem , Linfo-Histiocitose Hemofagocítica/genética , Imageamento por Ressonância Magnética , Neuroimagem , Estudos Retrospectivos
7.
Clin Oncol (R Coll Radiol) ; 33(12): e553-e560, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34340919

RESUMO

AIMS: The approach to potentially resectable non-small cell lung cancer (NSCLC) remains controversial. There is a benefit of neoadjuvant chemotherapy (NACT), but the ideal regimen is unknown. We evaluated the efficacy and safety of dose-dense NACT in potentially resectable NSCLC in this phase II trial. MATERIALS AND METHODS: Paclitaxel at 80 mg/m2 on days 1, 8 and 15 with AUC-6 carboplatin on day 1, 3 weekly for four cycles was evaluated as NACT. Patients with Eastern Cooperative Oncology Group performance status 0-2, stage IIB and IIIA (with only non-bulky N2 nodes) were included. The primary end point was the objective response rate. Secondary end points included toxicity, progression-free survival, recurrence-free survival, complete resection rate and overall survival. The relative dose intensity (RDI) was calculated to define tolerability (CTRI/2016/05/006916). RESULTS: In total, 37 patients were enrolled (median age 55 years). Most (78.8%) were smokers. Most patients had adenocarcinoma (57.6%) and stage IIIA disease (81.0%) according to the seventh American Joint Committee on Cancer staging system. Seventy-eight per cent of patients completed four cycles. The objective response rate was 75.6% with a complete response in 10.8%. The mean RDI of paclitaxel was 88.61%, with 68.0% of patients able to maintain an RDI ≥85.0%. In total, 187 toxicity events were recorded (120 grade 1, 64 grade 2 and three grade 3 events). Common toxicities were peripheral neuropathy (20.3%), myalgia (19.8%), nausea (15.7%) and neutropenia (10.2%). There were no treatment-related deaths. Seventeen patients underwent surgery (lobectomy 82.4%). After a median follow-up of 47 months (95% confidence interval 27-50.7 months), the median progression-free survival was 9.6 months (7.4-17.4) and overall survival was 29.2 months (16.0-37.2). CONCLUSION: Dose-dense paclitaxel-carboplatin is feasible, safe and efficacious and should be evaluated further in potentially resectable NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carboplatina/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Pessoa de Meia-Idade , Terapia Neoadjuvante , Paclitaxel/efeitos adversos
8.
Indian J Cancer ; 54(1): 209-213, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29199692

RESUMO

OBJECTIVE: Immunohistochemistry (IHC) with anaplastic lymphoma kinase (ALK) antibodies is considered as an economical screening method in lung adenocarcinomas. Automated Ventana D5F3-IHC is approved by US Food and Drug Administration for targeted therapy; however, the automated IHC apparatus are not widely used in most laboratories. We evaluated the performance of ALK IHC using the manual semiquantitative method to assess the concordance with Ventana ALK IHC assay. MATERIALS AND METHODS: We tested 156 cases of primary lung adenocarcinomas for ALK protein expression by D5F3-IHC. The intensity of cytoplasmic staining was classified as 0 or 1+/2+/3+ (weak/medium/strong). Binary score of positive and negative was used for Ventana assay. A comparison analysis and clinicopathological features were recorded. RESULTS: ALK IHC was positive in 25 (16.02%) cases, of which 18 were men and mostly nonsmokers. The mean age for all patients was 55 years, and for ALK IHC-positive cases was 48 years. Nine of 25 (36%) ALK IHC-positive cases showed signet ring cell and mucinous morphology. On comparison, all, but one, cases positive by manual method showed positive results by automated assay. IHC negative cases by manual method were negative by Ventana assay. CONCLUSION: Manual IHC is equally effective in the detection of ALK-rearranged cases as automated methods. It can be easily integrated as a screening method into routine practice thus reducing the cost of automated systems. However, equivocal cases should be tested by approved methods.


Assuntos
Adenocarcinoma/genética , Imuno-Histoquímica , Neoplasias Pulmonares/genética , Receptores Proteína Tirosina Quinases/genética , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Quinase do Linfoma Anaplásico , Anticorpos/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Receptores Proteína Tirosina Quinases/isolamento & purificação , Caracteres Sexuais , Fumantes
10.
Virusdisease ; 26(3): 151-62, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26396982

RESUMO

Camelpox virus (CMLV), a close variant of variola virus (VARV) infects camels worldwide. The zoonotic infections reported from India signify the need to study the host-range genes-responsible for host tropism. We report sequence and phylogenetic analysis of five host-range genes: cytokine response modifier B (crmB), chemokine binding protein (ckbp), viral schlafen-like (v-slfn), myxomavirus T4-like (M-T4-like) and b5r of CMLVs isolated from outbreaks in India. Comparative analysis revealed that these genes are conserved among CMLVs and shared 94.5-100 % identity at both nucleotide (nt) and amino acid (aa) levels. All genes showed identity (59.3-98.4 %) with cowpox virus (CPXV) while three genes-crmB, ckbp and b5r showed similarity (92-96.5 %) with VARVs at both nt and aa levels. Interestingly, three consecutive serine residue insertions were observed in CKBP protein of CMLV-Delhi09 isolate which was similar to CPXV-BR and VACVs, besides five point mutations (K53Q, N67I, F84S, A127T and E182G) were also similar to zoonotic OPXVs. Further, few inconsistent point mutation(s) were also observed in other gene(s) among Indian CMLVs. These indicate that different strains of CMLVs are circulating in India and these mutations could play an important role in adaptation of CMLVs in humans. The phylogeny revealed clustering of all CMLVs together except CMLV-Delhi09 which grouped separately due to the presence of specific point mutations. However, the topology of the concatenated phylogeny showed close evolutionary relationship of CMLV with VARV and TATV followed by CPXV-RatGer09/1 from Germany. The availability of this genetic information will be useful in unveiling new strategies to control emerging zoonotic poxvirus infections.

11.
Artigo em Inglês | MEDLINE | ID: mdl-23380173

RESUMO

BACKGROUND: Major depressive disorder (MDD) has been linked with accelerated bone loss leading to the development of low bone mineral density (BMD). Several mechanisms have been discussed as causative factors, e.g. lifestyle, selective serotonin reuptake inhibitor (SSRI) intake, or the influence of proinflammatory cytokines. METHODS: In a cross-sectional study of in-patients with a current episode of MDD, without somatic comorbidities, we determined various parameters of bone metabolism, inflammatory parameters and parameters of depression. BMD was measured by dual x-ray absorptiometry. RESULTS: Of 50 patients, only one had low BMD in any of the measure sites. Body mass index (BMI) correlated positively with Z-scores. 83.3% of the examined patients had elevated osteoprotegerin (OPG) levels. SSRI intake did not have an effect on BMD. BMD in the femoral neck was significantly lower in smokers. We also found a positive correlation between the level of physical activity and osteocalcin levels. CONCLUSIONS: In our sample, young to middle-aged, somatically healthy, and acutely depressed patients with a history of MDD showed no reduction of BMD. This could be due to compensatory mechanisms, as suggested by elevated OPG levels. Physical activity and high BMI could also have served as protective factors. Still, as patients with MDD often suffer from comorbidities or take medication with a negative effect on bone, this population should be appreciated as a high-risk group for the development of osteopenia and osteoporosis.


Assuntos
Densidade Óssea/fisiologia , Osso e Ossos/metabolismo , Transtorno Depressivo Maior/complicações , Doenças Metabólicas/patologia , Absorciometria de Fóton , Adulto , Índice de Massa Corporal , Citocinas/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoprotegerina/metabolismo , Adulto Jovem
12.
Gene Ther ; 19(8): 872-6, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22551777

RESUMO

Patients with X-linked severe combined immunodeficiency (SCID-X1) were successfully cured following gene therapy with a gamma-retroviral vector (gRV) expressing the common gamma chain of the interleukin-2 receptor (IL2RG). However, 5 of 20 patients developed leukemia from activation of cellular proto-oncogenes by viral enhancers in the long-terminal repeats (LTR) of the integrated vector. These events prompted the design of a gRV vector with self-inactivating (SIN) LTRs to enhance vector safety. Herein we report on the production of a clinical-grade SIN IL2RG gRV pseudotyped with the Gibbon Ape Leukemia Virus envelope for a new gene therapy trial for SCID-X1, and highlight variables that were found to be critical for transfection-based large-scale SIN gRV production. Successful clinical production required careful selection of culture medium without pre-added glutamine, reduced exposure of packaging cells to cell-dissociation enzyme, and presence of cations in wash buffer. The clinical vector was high titer; transduced 68-70% normal human CD34(+) cells, as determined by colony-forming unit assays and by xenotransplantation in immunodeficient NOD.CB17-Prkdc(scid)/J (nonobese diabetic/severe combined immunodeficiency (NOD/SCID)) and NOD.Cg-Prkdc(scid) Il2rg(tm1Wjl)/SzJ (NOD/SCID gamma (NSG))) mice; and resulted in the production of T cells in vitro from human SCID-X1 CD34(+) cells. The vector was certified and released for the treatment of SCID-X1 in a multi-center international phase I/II trial.


Assuntos
Vetores Genéticos , Subunidade gama Comum de Receptores de Interleucina/genética , Retroviridae/genética , Doenças por Imunodeficiência Combinada Ligada ao Cromossomo X/terapia , Animais , Técnicas de Transferência de Genes , Humanos , Vírus da Leucemia do Macaco Gibão/genética , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Sequências Repetidas Terminais , Transdução Genética
13.
Gene Ther ; 19(3): 246-54, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21753795

RESUMO

The need for γ-retroviral (gRV) vectors with a self-inactivating (SIN) design for clinical application has prompted a shift in methodology of vector manufacturing from the traditional use of stable producer lines to transient transfection-based techniques. Herein, we set out to define and optimize a scalable manufacturing process for the production of gRV vectors using transfection in a closed-system bioreactor in compliance with current good manufacturing practices (cGMP). The process was based on transient transfection of 293T cells on Fibra-Cel disks in the Wave Bioreactor. Cells were harvested from tissue culture flasks and transferred to the bioreactor containing Fibra-Cel in the presence of vector plasmid, packaging plasmids and calcium-phosphate in Dulbecco's modified Eagle's medium and 10% fetal bovine serum. Virus supernatant was harvested at 10-14 h intervals. Using optimized procedures, a total of five ecotropic cGMP-grade gRV vectors were produced (9 liters each) with titers up to 3.6 × 10(7) infectious units per milliliter on 3T3 cells. One GMP preparation of vector-like particles was also produced. These results describe an optimized process for the generation of SIN viral vectors by transfection using a disposable platform that allows for the generation of clinical-grade viral vectors without the need for cleaning validation in a cost-effective manner.


Assuntos
Reatores Biológicos , Gammaretrovirus/genética , Vetores Genéticos/isolamento & purificação , Vetores Genéticos/normas , Transfecção/métodos , Animais , Técnicas de Cultura Celular por Lotes/métodos , Técnicas de Cultura Celular por Lotes/normas , Biotecnologia , Linhagem Celular , Gammaretrovirus/isolamento & purificação , Humanos , Camundongos , Controle de Qualidade
14.
J Indian Soc Pedod Prev Dent ; 28(4): 293-6, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21273719

RESUMO

Peripheral giant cell granuloma is a benign reactive lesion of gingiva. It manifests as a firm, soft, bright nodule or as a sessile or pedunculate mass. This article reports the management of peripheral giant cell granuloma in a 12-year-old boy by surgical excision.


Assuntos
Doenças da Gengiva/cirurgia , Granuloma de Células Gigantes/cirurgia , Criança , Diagnóstico Diferencial , Diastema/etiologia , Doenças da Gengiva/complicações , Doenças da Gengiva/patologia , Granuloma de Células Gigantes/complicações , Granuloma de Células Gigantes/patologia , Humanos , Masculino , Maxila
15.
Gene Ther ; 14(17): 1298-304, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17597793

RESUMO

The woodchuck hepatitis virus post-transcriptional regulatory element (WPRE) increases transgene expression from a variety of viral vectors, although the precise mechanism is not known. WPRE is most effective when placed downstream of the transgene, proximal to the polyadenylation signal. We hypothesized that WPRE likely reduces viral mRNA readthrough transcription by improving transcript termination, which in turn would increase viral titers and expression. Using a Cre-lox-mediated plasmid-based assay, we found significant readthrough transcription from gamma-retroviral vector (RV) long terminal repeat (wt RV-LTR) and RV LTR with a self-inactivating deletion (SIN RV-LTR). WPRE, when placed upstream of the RV LTRs, significantly reduced readthrough transcription. Readthrough, present at much lower levels with the SIN HIV-1 LV-LTR, was also reduced with WPRE. When placed in RV vectors, WPRE increased total RV genomic mRNA; and increased viral titers from transiently transfected 293T cells and stable PG13 producer cells by 7- to 15-fold. The mechanism of increased titers and expression was not due to increased nuclear mRNA export, increased rate of viral transcription or a significant increase in viral mRNA half-life. Our results showed that WPRE improved vector genomic transcript termination to increase titers and expression from RVs.


Assuntos
Engenharia Genética , Vetores Genéticos/genética , Vírus da Hepatite B da Marmota/genética , Elementos Reguladores de Transcrição , Retroviridae/genética , Transcrição Gênica , Animais , Linhagem Celular , Expressão Gênica , Regulação Viral da Expressão Gênica , Vetores Genéticos/metabolismo , Humanos , Vírus da Leucemia Murina/genética , Processamento Pós-Transcricional do RNA , Fases de Leitura , Vírus da Imunodeficiência Símia/genética , Sequências Repetidas Terminais , Transfecção , Transgenes
16.
Biochem Soc Trans ; 34(Pt 5): 705-10, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17052179

RESUMO

Herpesviridae comprises over 120 viruses infecting a wide range of vertebrates including humans and livestock. Herpesvirus infections typically produce dermal lesions or immune cell destruction, but can also lead to oncogenesis, especially with KSHV (Kaposi's sarcoma-associated herpesvirus). All herpesviruses are nuclear replicating viruses that subvert cellular processes such as nucleocytoplasmic transport for their advantage. For virus replication to take over the cell and produce lytic infection requires that virus gene expression outpace that of the host cell. KSHV ORF57 (open reading frame 57) appears to play a major role in this by (i) serving as a nuclear export receptor to carry intronless viral mRNAs out of the nucleus and (ii) inhibiting expression of intron-containing host mRNAs. As most of the virally encoded mRNAs are intronless compared with host cell mRNAs, these two mechanisms are critical to overcoming host gene expression.


Assuntos
Regulação Viral da Expressão Gênica , Herpesviridae/genética , Herpesviridae/isolamento & purificação , Proteínas Repressoras/genética , Sarcoma de Kaposi/virologia , Transativadores/genética , Proteínas Virais/genética , Núcleo Celular/fisiologia , Núcleo Celular/virologia , Citoplasma/fisiologia , Citoplasma/virologia , Humanos , Transporte Proteico , Vírus de RNA/genética , RNA Mensageiro/genética
17.
Vet Res Commun ; 26(7): 513-22, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12416865

RESUMO

Outer membrane proteins (OMP) of P. multocida (serotype B:2) field isolates (n = 6) and a vaccine strain (P-52) were extracted by a sarkosyl method and characterized using SDS-PAGE and immunoblotting. About 20 polypeptide bands were observed in the profile of the vaccine strain with MW ranging from 16 to 90 kDa and, based on band thickness and intensity of staining, three polypeptides of MW 31, 33 and 37 kDa were considered to be the major OMPs. The profiles of the field isolates showed minor differences when compared with that of the vaccine strain. The OMP of 33 kDa was only expressed by the vaccine strain. Four field isolates expressed an OMP of 39 kDa, which did not appear in the profiles of the remaining two field isolates and the P-52 strain. Similarly, an OMP of 25 kDa was exclusively seen in the profile of a single isolate. By immunoblotting studies, using anti-P. multocida (P-52) whole-cell hyperimmune serum raised in rabbits as well as buffalo immune sera, it became evident that the polypeptide of 37 kDa was the most antigenic OMP in the profiles of all the isolates, including the P-52 strain. Other polypeptides were either weakly antigenic or visible in the profile of only a few of the isolates. The study thus identified the major OMP of P. multocida (B:2) and suggested that this highly antigenic 37 kDa OMP has potential for further protective and immunodiagnostic studies.


Assuntos
Proteínas da Membrana Bacteriana Externa/análise , Septicemia Hemorrágica/microbiologia , Septicemia Hemorrágica/veterinária , Pasteurella multocida/química , Pasteurella multocida/isolamento & purificação , Animais , Antígenos de Bactérias/análise , Antígenos de Bactérias/química , Antígenos de Bactérias/imunologia , Proteínas da Membrana Bacteriana Externa/química , Proteínas da Membrana Bacteriana Externa/imunologia , Vacinas Bacterianas/imunologia , Búfalos/microbiologia , Bovinos/microbiologia , Surtos de Doenças , Eletroforese em Gel de Poliacrilamida , Septicemia Hemorrágica/epidemiologia , Septicemia Hemorrágica/imunologia , Immunoblotting , Índia/epidemiologia , Pasteurella multocida/imunologia , Coelhos
18.
Mol Ther ; 4(4): 331-8, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11592836

RESUMO

Successful treatment of blood disorders by gene therapy has several complications, one of which is the frequent lack of selective advantage of genetically corrected cells. Erythropoietic protoporphyria (EPP), caused by a ferrochelatase deficiency, is a good model of hematological genetic disorders with a lack of spontaneous in vivo selection. This disease is characterized by accumulation of protoporphyrin in red blood cells, bone marrow, and other organs, resulting in severe skin photosensitivity. Here we develop a self-inactivating lentiviral vector containing human ferrochelatase cDNA driven by the human ankyrin-1/beta-globin HS-40 chimeric erythroid promoter/enhancer. We collected bone marrow cells from EPP male donor mice for lentiviral transduction and injected them into lethally irradiated female EPP recipient mice. We observed a high transduction efficiency of hematopoietic stem cells resulting in effective gene therapy of primary and secondary recipient EPP mice without any selectable system. Skin photosensitivity was corrected for all secondary engrafted mice and was associated with specific ferrochelatase expression in the erythroid lineage. An erythroid-specific expression was sufficient to reverse most of the clinical and biological manifestations of the disease. This improvement in the efficiency of gene transfer with lentiviruses may contribute to the development of successful clinical protocols for erythropoietic diseases.


Assuntos
Células da Medula Óssea/metabolismo , Modelos Animais de Doenças , Terapia Genética/métodos , Lentivirus/genética , Porfiria Hepatoeritropoética/genética , Porfiria Hepatoeritropoética/terapia , Animais , Southern Blotting , Transplante de Medula Óssea , Linhagem Celular , Elementos Facilitadores Genéticos/genética , Feminino , Ferroquelatase/genética , Ferroquelatase/metabolismo , Ferroquelatase/uso terapêutico , Expressão Gênica/genética , Vetores Genéticos/genética , Humanos , Lentivirus/fisiologia , Masculino , Camundongos , Especificidade de Órgãos , Porfiria Hepatoeritropoética/enzimologia , Porfiria Hepatoeritropoética/patologia , Porfirinas/metabolismo , Regiões Promotoras Genéticas/genética , Protoporfiria Eritropoética , Pele/patologia , Transdução Genética
19.
Blood ; 98(9): 2664-72, 2001 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11675336

RESUMO

Use of oncoretroviral vectors in gene therapy for hemoglobinopathies has been impeded by low titer vectors, genetic instability, and poor expression. Fifteen self- inactivating (SIN) lentiviral vectors using 4 erythroid promoters in combination with 4 erythroid enhancers with or without the woodchuck hepatitis virus postregulatory element (WPRE) were generated using the enhanced green fluorescent protein as a reporter gene. Vectors with high erythroid-specific expression in cell lines were tested in primary human CD34(+) cells and in vivo in the murine bone marrow (BM) transplantation model. Vectors containing the ankyrin-1 promoter showed high-level expression and stable proviral transmission. Two vectors containing the ankyrin-1 promoter and 2 erythroid enhancers (HS-40 plus GATA-1 or HS-40 plus 5-aminolevulinate synthase intron 8 [I8] enhancers) and WPRE expressed at levels higher than the HS2/beta-promoter vector in bulk unilineage erythroid cultures and individual erythroid blast-forming units derived from human BM CD34(+) cells. Sca1(+)/lineage(-) Ly5.1 mouse hematopoietic cells, transduced with these 2 ankyrin-1 promoter vectors, were injected into lethally irradiated Ly5.2 recipients. Eleven weeks after transplantation, high-level expression was seen from both vectors in blood (63%-89% of red blood cells) and erythroid cells in BM (70%-86% engraftment), compared with negligible expression in myeloid and lymphoid lineages in blood, BM, spleen, and thymus (0%-4%). The I8/HS-40-containing vector encoding a hybrid human beta/gamma-globin gene led to 43% to 113% human gamma-globin expression/copy of the mouse alpha-globin gene. Thus, modular use of erythroid-specific enhancers/promoters and WPRE in SIN-lentiviral vectors led to identification of high-titer, stably transmitted vectors with high-level erythroid-specific expression for gene therapy of red cell diseases.


Assuntos
Células Precursoras Eritroides/metabolismo , Vetores Genéticos/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Lentivirus/genética , Transdução Genética/métodos , Animais , Antígenos CD34 , Células da Medula Óssea , Transplante de Medula Óssea , Elementos Facilitadores Genéticos , Expressão Gênica , Regulação Viral da Expressão Gênica , Vetores Genéticos/normas , Proteínas de Fluorescência Verde , Vírus da Hepatite B da Marmota/genética , Humanos , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Camundongos , Modelos Animais , Regiões Promotoras Genéticas , Processamento Pós-Transcricional do RNA/genética , Transdução Genética/normas , gama-Globulinas/genética , gama-Globulinas/metabolismo
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