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1.
Am J Transplant ; 17(8): 2178-2185, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28489305

RESUMO

Since the first attempt of pig-to-primate liver xenotransplantation (LXT) in 1968, survival has been limited. We evaluated a model utilizing α-1,3-galactosyltransferase knockout donors, continuous posttransplant infusion of human prothrombin concentrate complex, and immunosuppression including anti-thymocyte globulin, FK-506, methylprednisone, and costimulation blockade (belatacept, n = 3 or anti-CD40 mAb, n = 1) to extend survival. Baboon 1 remained well until postoperative day (POD) 25, when euthanasia was required because of cholestasis and plantar ulcers. Baboon 2 was euthanized following a seizure on POD 5, despite normal liver function tests (LFTs) and no apparent pathology. Baboon 3 demonstrated initial stable liver function but was euthanized on POD 8 because of worsening LFTs. Pathology revealed C4d positivity, extensive hemorrhagic necrosis, and a focal cytomegalovirus inclusion. Baboon 4 was clinically well with stable LFTs until POD29, when euthanasia was again necessitated by plantar ulcerations and rising LFTs. Final pathology was C4d negative and without evidence of rejection, inflammation, or thrombotic microangiopathy. Thus, nearly 1-mo rejection-free survival has been achieved following LXT in two of four consecutive recipients, demonstrating that the porcine liver can support life in primates for several weeks and has encouraging potential for clinical application as a bridge to allotransplantation for patients with acute-on-chronic or fulminant hepatic failure.


Assuntos
Fatores de Coagulação Sanguínea/metabolismo , Sobrevivência de Enxerto/efeitos dos fármacos , Imunossupressores/farmacologia , Transplante de Fígado/mortalidade , Transplante Heterólogo , Animais , Animais Geneticamente Modificados , Sobrevivência de Enxerto/imunologia , Papio , Taxa de Sobrevida , Suínos
2.
Am J Transplant ; 15(4): 974-83, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25676635

RESUMO

Previous attempts of α-1,3-galactocyltransferase knockout (GalTKO) pig bone marrow (BM) transplantation (Tx) into baboons have demonstrated a loss of macro-chimerism within 24 h in most cases. In order to achieve improved engraftment with persistence of peripheral chimerism, we have developed a new strategy of intra-bone BM (IBBM) Tx. Six baboons received GalTKO BM cells, with one-half of the cells transplanted into the bilateral tibiae directly and the remaining cells injected intravenously (IBBM/BM-Tx) with a conditioning immunosuppressive regimen. In order to assess immune responses induced by the combined IBBM/BM-Tx, three recipients received donor SLA-matched GalTKO kidneys in the peri-operative period of IBBM/BM-Tx (Group 1), and the others received kidneys 2 months after IBBM/BM-Tx (Group 2). Peripheral macro-chimerism was continuously detectable for up to 13 days (mean 7.7 days; range 3-13) post-IBBM/BM-Tx and in three animals, macro-chimerism reappeared at days 10, 14 and 21. Pig CFUs, indicating porcine progenitor cell engraftment, were detected in the host BM in four of six recipients on days 14, 15, 19 and 28. In addition, anti-pig unresponsiveness was observed by in vitro assays. GalTKO/pCMV-kidneys survived for extended periods (47 and 60 days). This strategy may provide a potent adjunct for inducing xenogeneic tolerance through BM-Tx.


Assuntos
Células da Medula Óssea/citologia , Xenoenxertos , Animais , Transplante de Medula Óssea , Humanos , Incidência , Papio , Suínos
3.
Ann Oncol ; 26(4): 756-761, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25595936

RESUMO

BACKGROUND: A rare recurrent missense variant in HOXB13 (rs138213197/G84E) was recently reported to be associated with hereditary prostate cancer. Population-based studies have established that, since the frequency of this single-nucleotide polymorphism (SNP) varies between geographic regions, the associated proportion of prostate cancer (PrCa) risk contribution is also highly variable by country. PATIENTS AND METHODS: This is the largest comprehensive case-control study assessing the prevalence of the HOXB13 G84E variant to date and is the first in the UK population. We genotyped 8652 men diagnosed with PrCa within the UK Genetic Prostate Cancer Study (UKGPCS) and 5252 healthy men from the UK ProtecT study. RESULTS: HOXB13 G84E was identified in 0.5% of the healthy controls and 1.5% of the PrCa cases, and it was associated with a 2.93-fold increased risk of PrCa [95% confidence interval (CI) 1.94-4.59; P = 6.27 × 10(-8)]. The risk was even higher among men with family history of PrCa [odds ratio (OR) = 4.53, 95% CI 2.86-7.34; P = 3.1 × 10(-8)] and in young-onset PrCa (diagnosed up to the age of 55 years; OR = 3.11, 95% CI 1.98-5.00; P = 6.1 × 10(-7)). There was no significant association between Gleason Score, presenting prostate specific antigen, tumour-node-metastasis (TNM) stage or NCCN risk group and carrier status. HOXB13 G84E was not associated with overall or cancer-specific survival. We found that the polygenic PrCa risk score (PR score), calculated using the 71 known single-nucleotide polymorphisms (SNPs) associated with PrCa and the HOXB13 G84E variant act multiplicatively on PrCa risk. Based on the estimated prevalence and risk, this rare variant explains ∼1% of the familial risk of PrCa in the UK population. CONCLUSIONS: The clinical importance of HOXB13 G84E in PrCa management has not been established. This variant was found to have no effect on prognostic implications but could be used for stratifying screening, by identifying men at high risk. CLINICAL TRIALS NUMBERS: Prostate Testing for Cancer and Treatment (ProtecT): NCT02044172. UK GENETIC PROSTATE CANCER STUDY: Epidemiology and Molecular Genetics Studies (UKGPCS): NCT01737242.


Assuntos
Predisposição Genética para Doença , Mutação em Linhagem Germinativa/genética , Proteínas de Homeodomínio/genética , Polimorfismo de Nucleotídeo Único/genética , Próstata/metabolismo , Neoplasias da Próstata/genética , Idoso , Estudos de Casos e Controles , Seguimentos , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Prevalência , Prognóstico , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , Fatores de Risco , Taxa de Sobrevida , Reino Unido
4.
Br J Cancer ; 104(1): 175-7, 2011 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-21119657

RESUMO

BACKGROUND: The ratio of digit lengths is fixed in utero, and may be a proxy indicator for prenatal testosterone levels. METHODS: We analysed the right-hand pattern and prostate cancer risk in 1524 prostate cancer cases and 3044 population-based controls. RESULTS: Compared with index finger shorter than ring finger (low 2D : 4D), men with index finger longer than ring finger (high 2D : 4D) showed a negative association, suggesting a protective effect with a 33% risk reduction (odds ratio (OR) 0.67, 95% confidence interval (CI) 0.57-0.80). Risk reduction was even greater (87%) in age group <60 (OR 0.13, 95% CI 0.09-0.21). CONCLUSION: Pattern of finger lengths may be a simple marker of prostate cancer risk, with length of 2D greater than 4D suggestive of lower risk.


Assuntos
Dedos/anatomia & histologia , Mãos/fisiologia , Neoplasias da Próstata/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/etiologia , Fatores de Risco
5.
Br J Cancer ; 103(6): 918-24, 2010 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-20736950

RESUMO

BACKGROUND: The germline BRCA2 mutation is associated with increased prostate cancer (PrCa) risk. We have assessed survival in young PrCa cases with a germline mutation in BRCA2 and investigated loss of heterozygosity at BRCA2 in their tumours. METHODS: Two cohorts were compared: one was a group with young-onset PrCa, tested for germline BRCA2 mutations (6 of 263 cases had a germline BRAC2 mutation), and the second was a validation set consisting of a clinical set from Manchester of known BRCA2 mutuation carriers (15 cases) with PrCa. Survival data were compared with a control series of patients in a single clinic as determined by Kaplan-Meier estimates. Loss of heterozygosity was tested for in the DNA of tumour tissue of the young-onset group by typing four microsatellite markers that flanked the BRCA2 gene, followed by sequencing. RESULTS: Median survival of all PrCa cases with a germline BRCA2 mutation was shorter at 4.8 years than was survival in controls at 8.5 years (P=0.002). Loss of heterozygosity was found in the majority of tumours of BRCA2 mutation carriers. Multivariate analysis confirmed that the poorer survival of PrCa in BRCA2 mutation carriers is associated with the germline BRCA2 mutation per se. CONCLUSION: BRCA2 germline mutation is an independent prognostic factor for survival in PrCa. Such patients should not be managed with active surveillance as they have more aggressive disease.


Assuntos
Genes BRCA2 , Mutação em Linhagem Germinativa , Neoplasias da Próstata/genética , Adulto , Idoso , Humanos , Perda de Heterozigosidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Análise de Sobrevida
6.
Am J Transplant ; 9(11): 2479-84, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19843029

RESUMO

Viral infections including those due to cytomegalovirus have been associated with accelerated cardiac allograft vasculopathy (CAV) in clinical trials and some animal models. Evidence demonstrating a direct causal relationship between such infections and de novo formation of coronary vascular lesions is lacking. Heterotopic murine cardiac transplants were performed in a parental to F1 combination in animals lacking both T- and B-lymphocytes (RAG(-/-)). Coronary vasculopathy developed almost exclusively in the presence of recipient infection with lymphocytic choriomeningitis virus but not in uninfected controls. This process was also dependent upon the presence of natural killer (NK) cells as depletion of NK cells abrogated the process. These data show that a viral infection in its native host, and not previously implicated in the production of CAV, can contribute to the development of advanced coronary vascular lesions in cardiac allotransplants in mice. These data also suggest that virus-induced CAV can develop via an NK-cell-dependent pathway in the absence of T- and B-lymphocytes.


Assuntos
Infecções por Arenaviridae/imunologia , Doença das Coronárias/virologia , Transplante de Coração , Hospedeiro Imunocomprometido , Células Matadoras Naturais/virologia , Vírus da Coriomeningite Linfocítica , Animais , Infecções por Arenaviridae/complicações , Linfócitos B/imunologia , Doença das Coronárias/imunologia , Sobrevivência de Enxerto/imunologia , Proteínas de Homeodomínio/genética , Células Matadoras Naturais/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Linfócitos T/imunologia , Imunologia de Transplantes , Transplante Homólogo
7.
J Trauma ; 47(5): 912-7, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10568721

RESUMO

BACKGROUND: Despite improvements in burn wound care, infections, particularly pneumonia, remain a major hurdle to recovery from thermal injury. After burns, a variety of systemic immune and inflammatory changes contribute to the risk of infection. Clinically, infection coupled with burn injury seems to adversely affect susceptibility to subsequent infection. METHODS: Using a mouse model of 10% total body surface area, full-thickness, third-degree burns with quantitative bacterial cultures of multiple tissues, the effect of graded intratracheal and intraperitoneal infections with Pseudomonas aeruginosa on the development of infection was assessed. RESULTS: P. aeruginosa infection of blood and lung were demonstrated in burned mice 4 hours after they received 1 to 7.2x10(5) P. aeruginosa intratracheally but not in unburned control mice. Disseminated infection from endogenous bacterial species (Proteus, Enterococcus, Streptococcus) involving the lungs, liver, blood, and subeschar space was observed in mice that received both burns and infection with P. aeruginosa (intraperitoneally and intratracheally) but not with infection or burn alone (p<0.01). After burns, pulmonary bacterial clearance was delayed in association with both pulmonary infection (7.2x10(5) P. aeruginosa intratracheally) and intraperitoneal infection (10(7) P. aeruginosa intraperitoneally). Histologically, diffuse pneumonitis was observed in mice that received burns and infection but not in mice with either infection or burns alone. CONCLUSION: Small thermal injuries coupled with transient infection of the lungs or peritoneum delay the clearance of bacteria from the lungs and contribute to infection of the lungs, liver, burn site, and blood by endogenous organisms. These studies support the synergy of relatively small thermal injuries with infectious exposures in the pathogenesis of pneumonia and systemic infections after burns.


Assuntos
Queimaduras/imunologia , Pneumonia Bacteriana/imunologia , Infecções por Pseudomonas/imunologia , Pseudomonas aeruginosa/imunologia , Sepse/imunologia , Infecção dos Ferimentos/imunologia , Animais , Infecção Hospitalar/imunologia , Humanos , Tolerância Imunológica/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Peritonite/imunologia , Fatores de Risco
8.
Br J Nurs ; 8(3): 165-8, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10222878

RESUMO

The first article in this two-part series on the review of the concept of triage (Vol 8(2): 86-102) examined the areas of waiting times, patient satisfaction and the difficulty of trying to implement universal standards into accident and emergency (A&E) departments because of their varying infrastructures. This article aims to identify the educational requirements needed to become a triage nurse. Indeed, none of the reviewed literature explicitly addresses this issue. Educational literature tends to focus on the scientific aspect of practice rather than acknowledging that art, where interactions between the nurse and patient are essentially social acts that can never be accounted for by science, is also an inherent part of nursing practice. This article also investigates and analyses the use of research methods utilized to investigate triage and suggests that a re-evaluation of these methods is needed if the true effects of triage are to be ascertained.


Assuntos
Enfermagem em Emergência/educação , Recursos Humanos de Enfermagem Hospitalar/educação , Triagem/métodos , Competência Clínica , Currículo , Humanos , Conhecimento , Modelos Educacionais , Avaliação das Necessidades , Pesquisa em Educação em Enfermagem , Teoria de Enfermagem
9.
Br J Nurs ; 8(2): 86-8, 101-2, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10214137

RESUMO

This article, the first of two parts, reviews the concept of triage. The purpose is to make sense of the literature, and to provide an overview of the triage process. Although there are areas of consensus within the literature on triage, e.g. that accident and emergency (A&E) attendances and waiting lists are continually increasing and that triage can partially remedy these negative trends, contradiction and inconsistency between authors' accounts of triage still dominates the literature. This article examines the concepts of waiting times and patient satisfaction. With regards to waiting times, it is suggested that a reassessment of government legislation affecting triage is required if the potential of the concept is to be ascertained. With reference to patient satisfaction, this article recommends that in order to establish whether triage enhances patient satisfaction, universal agreement on how to define it is essential. Within the reviewed literature this is presently elusive. Finally, this article contends that due to the varying infrastructures of A&E departments, implementing universal standards is extremely arduous.


Assuntos
Enfermagem em Emergência/métodos , Avaliação em Enfermagem/métodos , Triagem/métodos , Humanos , Descrição de Cargo , Modelos de Enfermagem , Satisfação do Paciente , Listas de Espera
10.
J Nat Prod ; 62(2): 358-60, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10075787

RESUMO

The structure of sphaeric acid (1), a novel succinic acid derivative isolated from the fermentation broth of a Sphaeropsis sp., was determined by spectral data and synthetic transformation to the diol of sphaeric acid and subsequently to a pair of gamma-lactones (2 and 3).


Assuntos
Fungos/química , Succinatos/isolamento & purificação , Estrutura Molecular , Análise Espectral , Estereoisomerismo , Succinatos/química
11.
Artigo em Inglês | MEDLINE | ID: mdl-11969567

RESUMO

We used interferometry to measure the electric-field-induced (i.e., electrostrictive) increase of the density of sulfur hexafluoride (SF6) near its critical point. The results at three temperatures (T(c)+5.0 mK, T(c)+10.0 mK, T(c)+30.0 mK with T(c)=319 K) agree with a calculation based on the Clausius-Mossotti relation and the restricted cubic model equation of state. To measure electrostriction, an inhomogeneous electric field (< or =26 kV/cm) was applied to the SF6 sample by charging a fine wire that passed through it. These measurements were performed in microgravity so that the small electrostrictive density changes (< or =3.5% in this paper) would not be complicated by stratification of the fluid's density induced by the Earth's gravity. The predicted shifts of the critical temperature and density resulting from the electric field were too small to detect.

12.
Thromb Res ; 89(1): 23-30, 1998 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-9610757

RESUMO

Heparin was coupled to DTPA using the bicyclic anhydride and labeled with Indium-111. This resulted in a radiochemically pure preparation (greater than 95% activity in one peak) as determined by high pressure liquid radiochromatography and did not affect the anticoagulant properties of heparin. Biodistribution in the rat at 1, 20, and 60 minutes after intravenous injection showed rapid blood clearance with uptake in the liver followed by bone and kidney when expressed as percent injected total dose per organ and liver followed by kidney and spleen when expressed as percent injected total dose per gram. Blood elimination in the rabbit was 18.5 minutes which decreased to 7.5 minutes when followed by the injection of protamine. Radioactivity cleared from the liver and lungs as a single exponential with a half-time of 30 minutes, but there was very rapid increase of radioactivity in the lungs, peaking at 1-2 minutes, following the injection of protamine. Indium-111 DTPA-heparin may be used to study in vivo pharmacokinetics and biodistribution of heparin.


Assuntos
Anticoagulantes/farmacocinética , Heparina/farmacocinética , Ácido Pentético/farmacocinética , Compostos Radiofarmacêuticos/farmacocinética , Animais , Precipitação Química , Meia-Vida , Injeções Intravenosas , Taxa de Depuração Metabólica , Protaminas/química , Coelhos , Ratos , Distribuição Tecidual
13.
Br J Nurs ; 7(1): 26-30, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9495953

RESUMO

The prevalence of childhood asthma continues to rise, despite the introduction and implementation of innovative treatment methods. Asthma is now one of the most common childhood diseases. It is widely believed that the causes of asthma are likely to be multifactorial. Education on asthma management remains primarily focused on the parents of asthmatic children. A heightened emphasis on education aimed primarily at the child is imperative if the negative trends in morbidity and mortality of childhood asthma are to be curtailed. This article examines the need to correlate educational content with the cognitive ability of the asthmatic child.


Assuntos
Asma/terapia , Autocuidado , Adolescente , Asma/psicologia , Criança , Desenvolvimento Infantil , Pré-Escolar , Humanos , Lactente , Educação de Pacientes como Assunto , Poder Psicológico
14.
Am J Vet Res ; 58(7): 781-5, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9215458

RESUMO

OBJECTIVE: To address the physiologic mechanism of isoflurane-associated reduction in hematologic variables in ferrets. ANIMALS: 6 young adult female ferrets. PROCEDURE: Distribution of 99mTc-labeled autologous erythrocytes was measured by serial in vivo imaging. Data were recorded in 4 ferrets, using a gamma camera, immediately prior to anesthesia, 15 minutes after 2% isoflurane anesthesia in O2 via endotracheal tube, 1 minute prior to and throughout a 10-minute phenylephrine infusion, 20 and 40 minutes after termination of the phenylephrine infusion, and 45 minutes after termination of anesthesia. Blood indices were also measured at times that paralleled those for imaging. One ferret served as a conscious control (no anesthetic administration), and another as an isoflurane control (no phenylephrine administration). RESULTS: In ferrets under anesthesia, splenic radioactivity increased from baseline of 10.2 +/- 2.0% to 38.4 +/- 3.2% (mean +/- SEM; P < 0.05) of the injected dose. Splenic radioactivity decreased to 13.4 +/- 3.8% of the injected dose during phenylephrine infusion and to near baseline for the recovery image. Splenic radioactivity in the conscious control remained constant throughout the study, whereas that of the anesthetized control was persistently increased throughout administration of isoflurane. Percentage reduction of the 15-minute sample values, compared with baseline values for all hematologic indices, was: RBC count, 33% (P < 0.05); hemoglobin concentration, 34% (P < 0.05); hematocrit, 35% (P < 0.05); and plasma protein concentration, 20% (P < 0.05). All RBC variables returned to within 7 to 14% of baseline by 45 minutes after termination of anesthesia. CONCLUSION: Isoflurane anesthesia causes splenic sequestration of RBC in ferrets that is partially reversed by phenylephrine infusion or termination of anesthesia. Thus, investigators and clinicians should be cautious when interpreting hematologic findings in isoflurane-anesthetized ferrets, and accordingly, fluid treatment and transfusion should be planned.


Assuntos
Anestesia por Inalação/veterinária , Eritrócitos/metabolismo , Furões , Isoflurano , Animais , Contagem de Eritrócitos/efeitos dos fármacos , Contagem de Eritrócitos/veterinária , Eritrócitos/efeitos dos fármacos , Feminino , Furões/sangue , Hematócrito/veterinária , Isoflurano/farmacologia , Contagem de Leucócitos/efeitos dos fármacos , Contagem de Leucócitos/veterinária , Fígado/efeitos dos fármacos , Pertecnetato Tc 99m de Sódio , Baço/efeitos dos fármacos
15.
J Immunol ; 158(4): 1641-9, 1997 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-9029100

RESUMO

Donor-specific tolerance can be induced across a discordant xenogeneic barrier in T/NK cell-depleted, thymectomized (ATX) B10 mice by grafting of fetal pig thymic and liver tissue (FP THY/LIV) under the kidney capsule. We have now examined the phenotype and function of murine T cells that develop in FP THY/LIV grafts in these mice. Mouse CD4+ T cells reached normal levels in PBL by 14 wk, and were maintained up to 30 wk. Similar proportions of splenic CD4+ cells expressed the naive phenotype (CD45RBhighMEL-14+CD44low) in FP THY/LIV graft recipients and euthymic control mice. These CD4 cells were functional, demonstrating normal proliferative responses and up-regulation of CD25 and CD69 after activation by mitogens or alloantigens. They proliferated in response to the protein Ag KLH presented by host MHC following in vivo immunization. ATX B10 mice grafted with FP THY/LIV also cleared Pneumocystis carinii infections, whereas simultaneously-treated ATX B10 mice not receiving FP THY were unable to do so. Discordant xenogeneic thymus grafting can therefore restore immune competence. Thus, in addition to tolerance induction, xenogeneic thymic replacement might have a potential role in the reconstitution of immunity in patients afflicted with immunodeficiencies affecting the thymus.


Assuntos
Depleção Linfocítica , Linfócitos T/imunologia , Timectomia , Timo/transplante , Animais , Células Apresentadoras de Antígenos/metabolismo , Linfócitos T CD4-Positivos/imunologia , Diferenciação Celular/imunologia , Concanavalina A/farmacologia , Feto , Hemocianinas/imunologia , Hemocianinas/metabolismo , Imunidade Inata , Isoantígenos/farmacologia , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/microbiologia , Transplante de Fígado/imunologia , Ativação Linfocitária , Tecido Linfoide/citologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Nus , Pneumonia por Pneumocystis/imunologia , Suínos , Linfócitos T/microbiologia , Timo/microbiologia , Timo/cirurgia , Quimeras de Transplante , Transplante Heterólogo
17.
Nucl Med Biol ; 23(8): 995-8, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9004287

RESUMO

[18F]CP 99,219 [(1 alpha, 5 alpha, 6 alpha)-7-(6-amino-3-azabicyclo [3.1.0]hex-3-yl)-1-(2,4-difluorophenyl)-6-fluoro-1, 4-dihydro-4-oxo-1, 8-naphthyridine-3-carboxylic acid] was prepared by 18F for 19F exchange followed by reverse-phase HPLC purification. Studies of the effects of reaction time and temperature on 18F incorporation demonstrated that heating 1.0 mg of CP 99,219 in 0.5 cc of DMSO with 4.5 mg of K2CO3 and 24 mg of Kryptofix for 15 min at 160 degrees C results in the optimal compromise between radiochemical yield and purity. This method routinely provides radiochemical yields of 15-30% [EOS] with radiochemical purities of > 97%. Varying the concentration of CP 99,219 in the reaction mixture had no effect on yield. Biodistribution studies in rats demonstrated that significant concentrations of drug accumulate in most tissues. The tissues with the highest concentrations of drug were intestine, liver, kidney, and stomach.


Assuntos
Anti-Infecciosos/síntese química , Anti-Infecciosos/farmacocinética , Radioisótopos de Flúor/química , Fluoroquinolonas , Naftiridinas/síntese química , Naftiridinas/farmacocinética , Animais , Marcação por Isótopo/métodos , Masculino , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual
18.
Proc Natl Acad Sci U S A ; 93(15): 7460-3, 1996 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-8755495

RESUMO

The tissue distribution of CD4 lymphocytes in normal C57/BL mice and CD4 knockout mice was determined by biodistribution measurements and gamma camera imaging with an 111In-labeled rat IgG2b monoclonal antibody directed against the murine CD-4 antigen. In normal mice high concentrations of antibody accumulated in the spleen and lymph nodes. At 45 hr after injection, the concentration of radiolabel in the spleen and lymph nodes of normal mice were 10- to 20-fold greater than in the corresponding tissue of the CD4 knockout mice and nonlymphoid tissues of both types of mice. At 24 and 45 hr, gamma camera images showed high concentrations of radiolabeled antibody in lymph node and spleen of normal but not knockout mice. These results indicate that radioimmunoscintigraphy with 111In-anti-CD4 is an excellent method for studying tissue distribution of CD lymphocytes in mice. Using an equivalent anti-human CD antibody, this method might be useful for studying the pathophysiology of conditions in which these cells play a critical role and for monitoring therapies for these disorders.


Assuntos
Antígenos CD4/biossíntese , Linfócitos T CD4-Positivos/diagnóstico por imagem , Índio , Animais , Anticorpos Monoclonais , Antígenos CD4/análise , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/imunologia , Câmaras gama , Imunoglobulina G , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Especificidade de Órgãos , Radioimunodetecção/métodos , Ratos , Fatores de Tempo
19.
Radiology ; 197(3): 665-9, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7480736

RESUMO

PURPOSE: To test whether a nontargeted, long-circulating, synthetic polymer accumulates in areas of inflammation, with high capillary permeability and increased regional blood flow. MATERIALS AND METHODS: Methoxy poly(ethylene glycol)-poly-L-lysine (PL)-diethylenetriaminepentaacetic acid (MPEG-PL-DTPA) was labeled with technetium-99m for scintigraphy and with gadolinium for magnetic resonance (MR) imaging. Eleven Escherichia coli-infected rats were injected with 1.0 mCi (37 MBq) of Tc-99m-labeled MPEG-PL-DTPA for scintigraphy. Twelve rats underwent 1.5-T MR imaging after intravenous injection of gadolinium-labeled MPEG-PL-DTPA (35 mumol/kg). RESULTS: Tc-99m-labeled MPEG-PL-DTPA demonstrated nearly eight-fold higher accumulation in infected muscle when compared with normal muscle. Scintigrams and MR images showed areas of inflammation with peak accumulation at 24 hours after injection of Tc-99m- or gadolinium-labeled MPEG-PL-DTPA. CONCLUSION: Nontargeted, long-circulating, copolymers can efficiently accumulate in sites of inflammation and thus represent an alternative to inflammation-specific agents.


Assuntos
Meios de Contraste , Infecções por Escherichia coli/diagnóstico , Gadolínio DTPA , Gadolínio , Ácido Pentético/análogos & derivados , Polietilenoglicóis , Polilisina/análogos & derivados , Infecções dos Tecidos Moles/diagnóstico , Pentetato de Tecnécio Tc 99m , Animais , Permeabilidade Capilar , Meios de Contraste/farmacocinética , Modelos Animais de Doenças , Infecções por Escherichia coli/diagnóstico por imagem , Infecções por Escherichia coli/metabolismo , Infecções por Escherichia coli/patologia , Estudos de Viabilidade , Gadolínio/farmacocinética , Imunoglobulina G , Radioisótopos de Índio , Injeções Intravenosas , Imageamento por Ressonância Magnética , Masculino , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/metabolismo , Músculo Esquelético/microbiologia , Ácido Pentético/farmacocinética , Polietilenoglicóis/farmacocinética , Polilisina/farmacocinética , Cintilografia , Ratos , Ratos Sprague-Dawley , Fluxo Sanguíneo Regional , Infecções dos Tecidos Moles/diagnóstico por imagem , Infecções dos Tecidos Moles/metabolismo , Infecções dos Tecidos Moles/patologia , Pentetato de Tecnécio Tc 99m/farmacocinética , Coxa da Perna , Fatores de Tempo
20.
Magn Reson Med ; 34(3): 423-32, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7500882

RESUMO

A new technique for measuring tissue cellular volume fraction, based on an improved modeling of the dynamic distribution of Gd-DTPA and the effect of proton exchange, is described. This technique uses peak T1 enhancement and blood Gd-DTPA concentration to compute tissue cellular volume fraction. The feasibility of this technique is demonstrated with computer simulations that explore the limits of the simplifying assumptions (small vascular space, slow vascular-extravascular proton exchange), and by direct comparison of MR and radionuclide cell fraction measurements made in muscle, liver, and tumor tissue in a rat model. The computer simulations demonstrate that with slow to intermediate vascular proton exchange and vascular fractions less than 10% the error in our cell fraction measurements typically remains less than 10%. Consistent with this prediction, a direct comparison between MR and radionuclide measurements of cell fraction demonstrates mean percent differences of less than 10%:1.9% in muscle (n = 4); 9% in liver (n = 1) and 9.5% in tumor (n = 4). Similarly, for all rats studied, the MR-measured cell fractions (muscle (0.92 +/- 0.04, n = 20); liver (0.76 +/- 0.11, n = 9); whole tumor (0.69 +/- 0.15, n = 22)) agree with the cell fraction values reported in the literature. In general, the authors' results demonstrate the feasibility of a simple method for measuring tissue cell fraction that is robust across a broad range of vascular volume, flow, and exchange conditions. Consequently, this method may prove to be an important means for evaluating the response of tumors to therapy.


Assuntos
Tamanho Celular , Meios de Contraste , Fígado/citologia , Imageamento por Ressonância Magnética/métodos , Neoplasias Mamárias Experimentais/patologia , Músculo Esquelético/citologia , Compostos Organometálicos , Ácido Pentético/análogos & derivados , Animais , Simulação por Computador , Feminino , Gadolínio DTPA , Espectroscopia de Ressonância Magnética/métodos , Ratos , Ratos Endogâmicos F344
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