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1.
Int J Immunogenet ; 49(1): 22-29, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34555264

RESUMO

All UK H&I laboratories and transplant units operate under a single national kidney offering policy, but there have been variations in approach regarding when to undertake the pre-transplant crossmatch test. In order to minimize cold ischaemia times for deceased donor kidney transplantation we sought to find ways to be able to report a crossmatch result as early as possible in the donation process. A panel of experts in transplant surgery, nephrology, specialist nursing in organ donation and H&I (all relevant UK laboratories represented) assessed evidence and opinion concerning five factors that relate to the effectiveness of the crossmatch process, as follows: when the result should be ready for reporting; what level of donor HLA typing is needed; crossmatch sample type and availability; fairness and equity; risks and patient safety. Guidelines aimed at improving practice based on these issues are presented, and we expect that following these will allow H&I laboratories to contribute to reducing CIT in deceased donor kidney transplantation.


Assuntos
Transplante de Rim , Tipagem e Reações Cruzadas Sanguíneas , Isquemia Fria , Antígenos HLA , Teste de Histocompatibilidade , Humanos , Rim
2.
Nat Cancer ; 2(1): 34-48, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33997789

RESUMO

Pharmacologic inhibitors of cyclin-dependent kinases 4 and 6 (CDK4/6) were designed to induce cancer cell cycle arrest. Recent studies have suggested that these agents also exert other effects, influencing cancer cell immunogenicity, apoptotic responses, and differentiation. Using cell-based and mouse models of breast cancer together with clinical specimens, we show that CDK4/6 inhibitors induce remodeling of cancer cell chromatin characterized by widespread enhancer activation, and that this explains many of these effects. The newly activated enhancers include classical super-enhancers that drive luminal differentiation and apoptotic evasion, as well as a set of enhancers overlying endogenous retroviral elements that is enriched for proximity to interferon-driven genes. Mechanistically, CDK4/6 inhibition increases the level of several Activator Protein-1 (AP-1) transcription factor proteins, which are in turn implicated in the activity of many of the new enhancers. Our findings offer insights into CDK4/6 pathway biology and should inform the future development of CDK4/6 inhibitors.


Assuntos
Neoplasias da Mama , Fator de Transcrição AP-1 , Animais , Neoplasias da Mama/tratamento farmacológico , Pontos de Checagem do Ciclo Celular , Quinase 4 Dependente de Ciclina/genética , Feminino , Genes cdc , Humanos , Camundongos , Fator de Transcrição AP-1/genética
3.
FEBS J ; 288(19): 5629-5649, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33811729

RESUMO

Many metabolic phenotypes in cancer cells are also characteristic of proliferating nontransformed mammalian cells, and attempts to distinguish between phenotypes resulting from oncogenic perturbation from those associated with increased proliferation are limited. Here, we examined the extent to which metabolic changes corresponding to oncogenic KRAS expression differed from those corresponding to epidermal growth factor (EGF)-driven proliferation in human mammary epithelial cells (HMECs). Removal of EGF from culture medium reduced growth rates and glucose/glutamine consumption in control HMECs despite limited changes in respiration and fatty acid synthesis, while the relative contribution of branched-chain amino acids to the TCA cycle and lipogenesis increased in the near-quiescent conditions. Most metabolic phenotypes measured in HMECs expressing mutant KRAS were similar to those observed in EGF-stimulated control HMECs that were growing at comparable rates. However, glucose and glutamine consumption as well as lactate and glutamate production were lower in KRAS-expressing cells cultured in media without added EGF, and these changes correlated with reduced sensitivity to GLUT1 inhibitor and phenformin treatment. Our results demonstrate the strong dependence of metabolic behavior on growth rate and provide a model to distinguish the metabolic influences of oncogenic mutations and nononcogenic growth.


Assuntos
Neoplasias da Mama/genética , Carcinogênese/genética , Fator de Crescimento Epidérmico/genética , Transportador de Glucose Tipo 1/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Animais , Mama/crescimento & desenvolvimento , Mama/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proliferação de Células/genética , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Glucose/metabolismo , Transportador de Glucose Tipo 1/antagonistas & inibidores , Ácido Glutâmico/metabolismo , Glutamina/metabolismo , Humanos , Ácido Láctico/metabolismo , Glândulas Mamárias Humanas/crescimento & desenvolvimento , Glândulas Mamárias Humanas/patologia , Células Tumorais Cultivadas
4.
Nat Genet ; 52(8): 790-799, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32690948

RESUMO

Epigenetic processes govern prostate cancer (PCa) biology, as evidenced by the dependency of PCa cells on the androgen receptor (AR), a prostate master transcription factor. We generated 268 epigenomic datasets spanning two state transitions-from normal prostate epithelium to localized PCa to metastases-in specimens derived from human tissue. We discovered that reprogrammed AR sites in metastatic PCa are not created de novo; rather, they are prepopulated by the transcription factors FOXA1 and HOXB13 in normal prostate epithelium. Reprogrammed regulatory elements commissioned in metastatic disease hijack latent developmental programs, accessing sites that are implicated in prostate organogenesis. Analysis of reactivated regulatory elements enabled the identification and functional validation of previously unknown metastasis-specific enhancers at HOXB13, FOXA1 and NKX3-1. Finally, we observed that prostate lineage-specific regulatory elements were strongly associated with PCa risk heritability and somatic mutation density. Examining prostate biology through an epigenomic lens is fundamental for understanding the mechanisms underlying tumor progression.


Assuntos
Neoplasias da Próstata/genética , Linhagem Celular , Linhagem Celular Tumoral , Progressão da Doença , Epigenômica/métodos , Regulação Neoplásica da Expressão Gênica/genética , Células HEK293 , Fator 3-alfa Nuclear de Hepatócito/genética , Humanos , Masculino , Próstata/patologia , Neoplasias da Próstata/patologia , Receptores Androgênicos/genética , Sequências Reguladoras de Ácido Nucleico/genética
5.
Aliment Pharmacol Ther ; 48(3): 333-339, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29920697

RESUMO

BACKGROUND: Ustekinumab (USK) is licenced for intravenous induction and subcutaneous (S/C) maintenance in Crohn's disease. AIM: To evaluate ustekinumab trough concentrations and clinical response with exclusive subcutaneous ustekinumab induction. METHODS: Patients with Crohn's disease who initiated treatment with subcutaneous ustekinumab at a single academic centre were included in this pilot study. A dosage of 360 mg ustekinumab was given subcutaneously in divided doses; 180 mg at Week 0, 90 mg at Week 1 and 90 mg at Week 2, with corresponding ustekinumab trough concentrations assessed to Week 8. The primary outcome measures were trough serum ustekinumab levels and clinical remission at Week 8. Secondary outcome measures were trough serum ustekinumab levels at Week 1 & 2 and changes in C-reactive protein, albumin and faecal calprotectin at Week 8. RESULTS: Nineteen patients were included. Median Week 8 ustekinumab trough concentrations were 6.1 µg/mL (Inter-quartile range 4-9.8 µg/mL). There was a significant improvement in Harvey Bradshaw index from Week 0 (median HBI 5; interquartile range 2-8) to Week 8 (median HBI 1; interquartile range 0-3) (P = 0.002). C-reactive protein levels did not change significantly but faecal calprotectin improved significantly; median faecal calprotectin at Week 0 was 533 µg/g; at Week 8, it was 278 µg/g (P = 0.038). CONCLUSIONS: Ustekinumab trough concentrations are comparable whether ustekinumab induction treatment was administered subcutaneously or intravenously. A significant improvement in symptoms and faecal calprotectin was noted. These results support the use of subcutaneous induction as an alternative if there are barriers to intravenous induction.


Assuntos
Doença de Crohn/tratamento farmacológico , Quimioterapia de Indução/métodos , Ustekinumab/administração & dosagem , Ustekinumab/sangue , Administração Intravenosa , Adulto , Estudos de Coortes , Doença de Crohn/diagnóstico , Doença de Crohn/metabolismo , Feminino , Humanos , Injeções Subcutâneas , Masculino , Uso Off-Label , Projetos Piloto , Indução de Remissão , Fatores de Tempo , Resultado do Tratamento , Ustekinumab/farmacocinética
6.
J Eur Acad Dermatol Venereol ; 31(6): 978-985, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28045204

RESUMO

BACKGROUND: Recent studies report an increased risk of non-melanoma skin cancer (NMSC) in immunosuppressed patients with inflammatory bowel disease (IBD). Concurrently, paediatric IBD incidence is rising, with more patients now exposed to immunomodulators from a younger age. OBJECTIVES: To investigate NMSC incidence and to examine the risk associated with immunomodulators in the development of NMSC in patients with IBD. METHODS: This was a retrospective single-centre cohort study. Patients with IBD attending a tertiary adult hospital from 1994 to 2013 were included. Skin cancer incidence was compared with population data from the National Cancer Registry of Ireland (NCRI) to calculate standardized incidence ratio (SIR). Logistic regression was utilized for risk factor analysis. RESULTS: Two thousand and fifty-three patients with IBD were studied. The SIR for NMSC in patients with IBD taking immunomodulators overall was 1.8 (95% CI: 1.0-2.7) with age-specific rates significantly elevated across certain age categories. Exposure to thiopurines (OR: 5.26, 95% CI: 2.15-12.93, P < 0.001) and in particular thiopurines and/or tumour necrosis factor alpha (TNF-α) inhibitors (OR: 6.45, 95% CI: 2.69-15.95, P < 0.001) was significantly associated with NMSC. The majority (82%) of those exposed to a TNF-α inhibitor also had thiopurine exposure. CONCLUSIONS: Compliance with skin cancer preventative measures should be highlighted to all patients with IBD. There should be a low threshold for dermatology referral for immunosuppressed patients, particularly those with a history of exposure to dual immunomodulators from a young age.


Assuntos
Adjuvantes Imunológicos/uso terapêutico , Doenças Inflamatórias Intestinais/complicações , Melanoma/epidemiologia , Adulto , Feminino , Humanos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Masculino , Melanoma/complicações , Estudos Retrospectivos
7.
Bioinformatics ; 31(10): 1526-35, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25573922

RESUMO

MOTIVATION: Identifying and prioritizing somatic mutations is an important and challenging area of cancer research that can provide new insights into gene function as well as new targets for drug development. Most methods for prioritizing mutations rely primarily on frequency-based criteria, where a gene is identified as having a driver mutation if it is altered in significantly more samples than expected according to a background model. Although useful, frequency-based methods are limited in that all mutations are treated equally. It is well known, however, that some mutations have no functional consequence, while others may have a major deleterious impact. The spatial pattern of mutations within a gene provides further insight into their functional consequence. Properly accounting for these factors improves both the power and accuracy of inference. Also important is an accurate background model. RESULTS: Here, we develop a Model-based Approach for identifying Driver Genes in Cancer (termed MADGiC) that incorporates both frequency and functional impact criteria and accommodates a number of factors to improve the background model. Simulation studies demonstrate advantages of the approach, including a substantial increase in power over competing methods. Further advantages are illustrated in an analysis of ovarian and lung cancer data from The Cancer Genome Atlas (TCGA) project.


Assuntos
Biologia Computacional/métodos , Análise Mutacional de DNA/métodos , Genoma Humano , Neoplasias Pulmonares/genética , Modelos Estatísticos , Mutação/genética , Proteínas de Neoplasias/genética , Neoplasias Ovarianas/genética , Carcinoma de Células Escamosas/genética , Simulação por Computador , Interpretação Estatística de Dados , Feminino , Humanos
9.
Tech Coloproctol ; 18(1): 23-8, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23407916

RESUMO

BACKGROUND: This study evaluated the clinicopathological features and survival rates of patients with inflammatory bowel disease who developed colorectal cancer (CRC). METHODS: A retrospective review was performed on a prospectively maintained institutional database (1981-2011) to identify patients with inflammatory bowel disease who developed CRC. Clinicopathological parameters, management and outcomes were analysed. RESULTS: A total of 2,843 patients with inflammatory bowel disease were identified. One thousand six hundred and forty-two had ulcerative colitis (UC) and 1,201 had Crohn's disease (CD). Following exclusion criteria, there were 29 patients with biopsy-proven colorectal carcinoma, 22 of whom had UC and 7 had CD. Twenty-six patients had a preoperative diagnosis of malignancy/dysplasia; 16 of these were diagnosed at surveillance endoscopy. Nodal/distant metastasis was identified at presentation in 47 and 71 % of the UC and CD group, respectively. Operative morbidity for UC and CD was 33 and 17 %, respectively. Despite the less favourable operative outcomes following surgery management of UC-related CRC, overall 5-year survival was significantly better in the UC group compared to the CD group (41 vs. 29 %; p = 0.04) reflecting the difference in stage at presentation between the two groups. CONCLUSIONS: Patients who undergo surgery for UC-related CRC have less favourable short-term outcomes but present at a less advanced stage and have a more favourable long-term prognosis than similar patients with CRC and CD.


Assuntos
Adenocarcinoma/cirurgia , Colite Ulcerativa/complicações , Neoplasias Colorretais/cirurgia , Doença de Crohn/complicações , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
12.
Colorectal Dis ; 12(6): 570-3, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19438883

RESUMO

The conditions Juvenile Polyposis Syndrome (JPS) and Hereditary Mixed Polyposis Syndrome (HMPS) are associated with an increased risk of colorectal carcinoma. The genetic mechanisms which explain these conditions have until recently been poorly understood. Recent interest has focused on the transforming growth factor (TGF)-beta signalling pathway and, in particular, on mutations in the SMAD4 gene. However, not all cases of JPS and HMPS have mutations in SMAD4 and focus has now shifted to other components of the TGF-beta pathway to clarify the genetic mechanisms involved in these conditions. In this report, we describe the significance of a bone morphogenetic protein receptor type 1A gene mutation in an Irish family.


Assuntos
Polipose Adenomatosa do Colo/genética , Receptores de Proteínas Morfogenéticas Ósseas Tipo I/genética , Mutação , Adulto , Pólipos do Colo , Neoplasias Colorretais/genética , Feminino , Humanos , Masculino , Linhagem , Transdução de Sinais , Proteína Smad4/genética , Síndrome , Fator de Crescimento Transformador beta/fisiologia
13.
J Clin Pathol ; 62(5): 471-3, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19398597

RESUMO

Mutations of DNA mismatch repair genes are characterised by microsatellite instability and are implicated in carcinogenesis. This mutation susceptible phenotype has been extensively studied in patients with hereditary non-polyposis colon carcinoma, but little is known of the contribution of such mutations in other tumour types, particularly non-small-cell lung carcinoma. This report describes the occurrence of two synchronous lung tumours, one mimicking a metastatic colon carcinoma, in a male patient with a history of metachronous colonic carcinoma. Immunohistochemistry supported a pulmonary origin for both lesions. Mismatch repair protein immunohistochemistry showed loss of MSH2 and MSH6 expression in both colonic tumours and in one lung tumour showing enteric differentiation. Subsequent mutational analysis demonstrated a deleterious germline mutation of the MSH2 mismatch repair gene. The significance of these findings and the practical diagnostic difficulties encountered in this case are discussed.


Assuntos
Adenocarcinoma/genética , Neoplasias Colorretais/genética , Mutação em Linhagem Germinativa , Neoplasias Pulmonares/genética , Proteína 2 Homóloga a MutS/genética , Neoplasias Primárias Múltiplas/genética , Adenocarcinoma/patologia , Análise Mutacional de DNA/métodos , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias Primárias Múltiplas/patologia , Linhagem
14.
Aliment Pharmacol Ther ; 24(2): 351-9, 2006 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-16842462

RESUMO

BACKGROUND: Infliximab is recognized as an effective therapy in unresponsive luminal and fistulating Crohn's disease. The use of maintenance or 'on demand' therapy thereafter is controversial. AIM: To assess the need for maintenance infliximab therapy in a clinical setting where immunomodulatory agents are widely used and where episodic therapy is used in preference to maintenance therapy. METHODS: Ninety-three patients with Crohn's disease receiving infliximab; 72 with unresponsive luminal disease and 21 with fistulous disease. Data collected included disease site and duration, surgical and smoking history, initial response rates, duration of response maintenance and concomitant medications. RESULTS: Fifty-six of 72 (78%) patients with luminal disease and 11 of 21 (52%) with fistulous disease achieved an initial response. Ten of 67 responders required conversion to maintenance infliximab infusions, while 31 remain in remission. Patients with luminal disease and those who had not taken previous surgery had higher response rates to infliximab. Younger patients and those with small bowel disease had higher relapse rates following initial response. Three patients developed allergic reactions to infliximab and one patient died of progressive pulmonary disease 6 weeks after their first infusion. CONCLUSIONS: Many patients with Crohn's disease can be maintained successfully with an episodic infliximab regimen.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Doença de Crohn/tratamento farmacológico , Fármacos Gastrointestinais/uso terapêutico , Adulto , Intervalo Livre de Doença , Feminino , Humanos , Infliximab , Masculino , Pessoa de Meia-Idade , Recidiva
15.
Orbit ; 24(3): 211-4, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16169809

RESUMO

Primary cutaneous mucinous carcinoma of the eyelid is an adenocarcinoma of the eccrine glands. It is rare and locally aggressive but the prognosis following local excision, confirmed with tumour-free margins, is good. This tumour is usually described in the elderly. We present the occurrence, clinical and histological features, and management of this tumour in a young male.A 36-year-old male presented with a small cystic right lower lid lesion, which had increased in size and pigmentation over two years. He underwent excision biopsy for diagnostic purposes followed by Moh's micrographic surgical removal. The defect was repaired with an upper eyelid skin graft. A full oncological screen including whole-body computed tomography scan excluded the presence of primary mucinous carcinoma elsewhere and any metastatic spread. There has been no recurrence of tumour 18 months following excision. Ophthalmologists should be aware of the occurrence of this tumour in a younger age group than previously described. Moh's micrographic surgery is the most suitable method of treatment following exclusion of both distant primaries and metastases.


Assuntos
Adenocarcinoma Mucinoso/patologia , Adenocarcinoma Mucinoso/cirurgia , Neoplasias Palpebrais/patologia , Neoplasias Palpebrais/cirurgia , Adulto , Diagnóstico Diferencial , Humanos , Masculino , Cirurgia de Mohs
16.
Eye (Lond) ; 19(9): 972-80, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15389270

RESUMO

PURPOSE OF STUDY: To present a model for the assessment, investigation, and management of an atypical outbreak of infectious endophthalmitis of indeterminate aetiology. METHODS: A published statistical model was used to determine when the case-load constituted an outbreak. Intraocular surgery was discontinued and a multidisciplinary infection control team was formed aimed at identifying potential causative factors among the following categories: environment around theatre, preoperative preparation, intraoperative theatre practices, intraoperative surgical practices, postoperative practices, equipment maintenance guidelines, cleaning/sterilization practices, and microbiological screening. RESULTS: Five cases of postoperative endophthalmitis developed following uncomplicated phacoemulsification cataract surgery by different surgeons over a 7-month period. Despite full investigation no single focus of infection could be determined. Four out of five cases were culture positive. Three grew Streptococcus viridans of different strains. The fourth culture grew Staphylococcus aureus. In the absence of a single causative factor, it was postulated the combined effect of multiple potential factors may have led to an increased bacterial load and subsequent infection rate. Improved practices were initiated including new cleaning protocols to combat the build-up of debris on phacoemulsification instruments. Cataract surgery was resumed with 3-monthly microbiological monitoring. There have been no further cases in the 12 months following the changes. CONCLUSION: Outbreaks of endophthalmitis typically present over a short time period and could often be attributed to a single infective cause. We present our experience of detecting and managing this cluster and recommend a 'ground-up' multidisciplinary model to manage future outbreaks of this devastating condition.


Assuntos
Infecção Hospitalar/etiologia , Surtos de Doenças/prevenção & controle , Endoftalmite/etiologia , Infecções Oculares Bacterianas/etiologia , Modelos Organizacionais , Idoso , Idoso de 80 Anos ou mais , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/prevenção & controle , Endoftalmite/epidemiologia , Endoftalmite/prevenção & controle , Infecções Oculares Bacterianas/epidemiologia , Infecções Oculares Bacterianas/prevenção & controle , Feminino , Humanos , Controle de Infecções/métodos , Controle de Infecções/normas , Londres/epidemiologia , Masculino , Pessoa de Meia-Idade , Equipe de Assistência ao Paciente , Facoemulsificação , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Esterilização/métodos , Esterilização/normas
17.
J Leukoc Biol ; 74(2): 151-60, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12885930

RESUMO

There is currently no real treatment for blinding disorders that stem from the degeneration of cells in the retina and affect at least 50 million individuals worldwide. The excitement that accompanied the first studies showing the potential of retinal cell transplantation to alleviate the progress of blindness in such diseases as retinitis pigmentosa and age-related macular degeneration has lost some of its momentum, as attempts to apply research to the clinic have failed so far to provide effective treatments. What these studies have shown, however, is not that the approach is flawed but rather that the steps that need to be taken to achieve a viable, clinical treatment are many. This review summarizes the course of retinal transplant studies and points to obstacles that still need to be overcome to improve graft survival and efficacy and to develop a protocol that is effective in a clinical setting. Emphasis is given particularly to the consequences of introducing transplants to sites that have been considered immunologically privileged and to the role of the major histocompatibility complex classes I and II molecules in graft survival and rejection.


Assuntos
Retina/transplante , Degeneração Retiniana/cirurgia , Animais , Transplante de Células , Humanos , Epitélio Pigmentado Ocular/imunologia , Degeneração Retiniana/imunologia
18.
Proc Natl Acad Sci U S A ; 98(17): 9942-7, 2001 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-11504951

RESUMO

Royal College of Surgeons rats are genetically predisposed to undergo significant visual loss caused by a primary dysfunction of retinal pigment epithelial (RPE) cells. By using this model, we have examined the efficacy of subretinal transplantation of two independent human RPE cell lines each exhibiting genetic modifications that confer long-term stability in vitro. The two cell lines, a spontaneously derived cell line (ARPE19) and an extensively characterized genetically engineered human RPE cell line (h1RPE7), which expresses SV40 large T (tumor) antigen, were evaluated separately. Both lines result in a significant preservation of visual function as assessed by either behavioral or physiological techniques. This attenuation of visual loss correlates with photoreceptor survival and the presence of donor cells in the areas of rescued photoreceptors at 5 months postgrafting (6 months of age). These results demonstrate the potential of genetically modified human RPE cells for ultimate application in therapeutic transplantation strategies for retinal degenerative diseases caused by RPE dysfunction.


Assuntos
Proteínas do Olho/fisiologia , Epitélio Pigmentado Ocular/transplante , Proteínas Proto-Oncogênicas , Receptores Proteína Tirosina Quinases/deficiência , Degeneração Retiniana/terapia , Animais , Antígenos Transformantes de Poliomavirus/genética , Linhagem Celular Transformada/transplante , Sobrevivência Celular , Transformação Celular Viral , Proteínas do Olho/genética , Movimentos da Cabeça/fisiologia , Humanos , Fagocitose , Epitélio Pigmentado Ocular/citologia , Ratos , Ratos Mutantes , Receptores Proteína Tirosina Quinases/genética , Degeneração Retiniana/genética , Degeneração Retiniana/patologia , Segmento Externo da Célula Bastonete/metabolismo , Segmento Externo da Célula Bastonete/patologia , Limiar Sensorial , Vírus 40 dos Símios/genética , Colículos Superiores/fisiopatologia , Transplante Heterólogo , Testes Visuais , Campos Visuais , Percepção Visual , c-Mer Tirosina Quinase
19.
Invest Ophthalmol Vis Sci ; 41(2): 518-28, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10670484

RESUMO

PURPOSE: To examine whether congenic Schwann cells grafted into the subretinal space of dystrophic Royal College of Surgeons (RCS) rats can prevent photoreceptor loss and maintain visual function. METHODS: Purified neonatal Schwann cells derived from congenic rats were grafted into the subretinal space of 3- to 4-week-old dystrophic RCS rats. Graft placement was confirmed using Schwann cells labeled in vitro with the fluorescent dye Hoechst 33342 or in grafted eyes processed for electron microscopy (48-hour to 1-month survival). At longer intervals, up to 9 months after surgery, animals were examined for photoreceptor survival; preservation of a visual reflex, head-tracking to moving stripes; and preservation of visual receptive fields associated with the region of graft placement. RESULTS: One week after the graft was performed, Schwann cells had integrated into the subretinal space with little evidence of a reactive response. When screened for head-tracking to moving stripes, Schwann cell-grafted animals performed better than sham-treated or control dystrophic animals. Threshold sensitivity measurements and visual field assessment made by recording from the superior colliculus also showed a significant level of preserved function compared with control animals. Functional rescue was correlated with photoreceptor survival and could be observed for at least 9 months after grafting. CONCLUSIONS: Schwann cells injected into the subretinal space limit functional deterioration and prolong photoreceptor survival. It is suggested that they act by local release of growth factors that either support photoreceptors directly and/or stimulate phagocytosis in RPE cells.


Assuntos
Retina/cirurgia , Degeneração Retiniana/fisiopatologia , Degeneração Retiniana/cirurgia , Células de Schwann/transplante , Animais , Comportamento Animal/fisiologia , Benzimidazóis , Transplante de Células , Eletrofisiologia , Corantes Fluorescentes , Atividade Motora/fisiologia , Células Fotorreceptoras de Vertebrados/fisiologia , Ratos , Ratos Mutantes , Retina/patologia , Retina/fisiopatologia , Degeneração Retiniana/patologia , Degeneração Retiniana/prevenção & controle , Nervo Isquiático/citologia , Colículos Superiores/fisiologia , Visão Ocular/fisiologia , Campos Visuais/fisiologia
20.
J Med Chem ; 42(22): 4640-9, 1999 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-10579826

RESUMO

The synthesis of a series of novel analogues of lipid A, the active principle of lipopolysaccharide, is reported. In these compounds, the 1-O-phosphono and (R)-3-hydroxytetradecanoyl moieties of native Salmonella minnesota R595 lipid A have been replaced with hydrogen and the length of the normal fatty acyl residues has been systematically varied. Normal fatty acid chain length in the 3-O-desacyl monophosphoryl lipid A (MLA) series is shown to be a critical determinant of iNOS gene expression in activated mouse macrophages and the induction of proinflammatory cytokines in human peripheral monocytes. Examination of pyrogenicity in rabbits and lethal toxicity in D-galactosamine-treated mice shows that toxic effects in the MLA series can be ameliorated by modifying fatty acid chain length. When used as an adjuvant for tetanus toxoid vaccines, certain MLA derivatives enhance the production of tetanus toxoid-specific antibodies in mice.


Assuntos
Adjuvantes Imunológicos/síntese química , Lipídeo A/análogos & derivados , Lipídeo A/síntese química , Adjuvantes Imunológicos/química , Adjuvantes Imunológicos/farmacologia , Adjuvantes Imunológicos/toxicidade , Animais , Citocinas/metabolismo , Feminino , Febre/induzido quimicamente , Humanos , Imunoglobulina G/biossíntese , Técnicas In Vitro , Dose Letal Mediana , Lipídeo A/química , Lipídeo A/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/enzimologia , Camundongos , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo II , Coelhos , Salmonella/química , Relação Estrutura-Atividade , Toxoide Tetânico , Vacinação
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