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1.
Transplantation ; 104(8): 1591-1603, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32732836

RESUMO

BACKGROUND: Combined liver-kidney transplantation (CLKT) improves survival for liver transplant recipients with renal dysfunction; however, the tenuous perioperative hemodynamic and metabolic milieu in high-acuity CLKT recipients increases delayed graft function and kidney allograft failure. We sought to analyze whether delayed KT through pumping would improve kidney outcomes following CLKT. METHODS: A retrospective analysis (University of California Los Angeles [n = 145], Houston Methodist Hospital [n = 79]) was performed in all adults receiving CLKT at 2 high-volume transplant centers from February 2004 to January 2017, and recipients were analyzed for patient and allograft survival as well as renal outcomes following CLKT. RESULTS: A total of 63 patients (28.1%) underwent delayed implantation of pumped kidneys during CLKT (dCLKT) and 161 patients (71.9%) received early implantation of nonpumped kidneys during CLKT (eCLKT). Most recipients were high-acuity with median biologic model of end-stage liver disease (MELD) score of, 35 for dCLKT and 34 for eCLKT (P = ns). Pretransplant, dCLKT had longer intensive care unit stay, were more often intubated, and had greater vasopressor use. Despite this, dCLKT exhibited improved 1-, 3-, and 5-year patient and kidney survival (P = 0.02) and decreased length of stay (P = 0.001), kidney allograft failure (P = 0.012), and dialysis duration (P = 0.031). This reduced kidney allograft futility (death or continued need for hemodialysis within 3 mo posttransplant) for dCLKT (6.3%) compared with eCLKT (19.9%) (P = 0.013). CONCLUSIONS: Delayed implantation of pumped kidneys is associated with improved patient and renal allograft survival and decreased hospital length of stay despite longer kidney cold ischemia. These data should inform the ethical debate as to the futility of performing CLKT in high-acuity recipients.


Assuntos
Doença Hepática Terminal/cirurgia , Rejeição de Enxerto/epidemiologia , Transplante de Rim/efeitos adversos , Transplante de Fígado/efeitos adversos , Preservação de Órgãos/métodos , Idoso , Aloenxertos/imunologia , Aloenxertos/provisão & distribuição , Isquemia Fria/instrumentação , Isquemia Fria/métodos , Isquemia Fria/estatística & dados numéricos , Doença Hepática Terminal/complicações , Estudos de Viabilidade , Feminino , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto/imunologia , Humanos , Rim/imunologia , Transplante de Rim/ética , Transplante de Rim/métodos , Transplante de Rim/estatística & dados numéricos , Transplante de Fígado/ética , Transplante de Fígado/métodos , Transplante de Fígado/estatística & dados numéricos , Masculino , Futilidade Médica/ética , Pessoa de Meia-Idade , Preservação de Órgãos/instrumentação , Preservação de Órgãos/estatística & dados numéricos , Perfusão/instrumentação , Perfusão/métodos , Perfusão/estatística & dados numéricos , Insuficiência Renal/etiologia , Insuficiência Renal/cirurgia , Estudos Retrospectivos , Fatores de Tempo , Tempo para o Tratamento/estatística & dados numéricos , Transplante Homólogo/efeitos adversos , Transplante Homólogo/ética , Transplante Homólogo/métodos , Resultado do Tratamento
2.
Tuberculosis (Edinb) ; 116S: S78-S88, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31080090

RESUMO

BACKGROUND: Head and neck tuberculosis (HNTB), including cervical lymphadenopathy, is the most common extrapulmonary manifestation of TB. The proposed study investigated the epidemiologic and clinical characteristics of HNTB. MATERIALS AND METHODS: A literature search was conducted via PubMed, Embase, Cochrane Library and Wanfang for keywords (tuberculosis, head and neck, laryngeal, pharyngeal, tongue, oropharyngeal, nasopharyngeal, and oral cavity). Scientific articles published from January 1990 through July 2017 were selected and reviewed to assess the epidemiology, presentation, diagnosis and treatment of HNTB disease. RESULTS: Results from the included 57 studies revealed that the majority of HNTB cases were age<40 years and female. The most common HNTB sites were cervical lymph nodes (87.9%), followed by larynx (8.7%). Involvement of other HN-regions was rare (3.4%). Multidrug resistant TB was not common among the majority of studies. Given the paucibacillary nature of HNTB, sputum tests did not have a good performance on HNTB diagnosis. Most of HNTB cases were diagnosed by fine-needle aspiration, cytology and excision biopsies in combination with clinical presentations. CONCLUSION: HNTB disease is an important manifestation in the diagnostic process in an otolaryngologist practice. The developments of rapid, ultrasensitive, simple and cost-effective high-throughput methods for early diagnosis of HNTB are urgently needed.


Assuntos
Tuberculose Laríngea , Tuberculose dos Linfonodos , Tuberculose Bucal , Adulto , Antituberculosos/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Resultado do Tratamento , Tuberculose Laríngea/diagnóstico , Tuberculose Laríngea/tratamento farmacológico , Tuberculose Laríngea/epidemiologia , Tuberculose Laríngea/microbiologia , Tuberculose dos Linfonodos/diagnóstico , Tuberculose dos Linfonodos/tratamento farmacológico , Tuberculose dos Linfonodos/epidemiologia , Tuberculose dos Linfonodos/microbiologia , Tuberculose Bucal/diagnóstico , Tuberculose Bucal/tratamento farmacológico , Tuberculose Bucal/epidemiologia , Tuberculose Bucal/microbiologia , Adulto Jovem
3.
Tuberculosis (Edinb) ; 106: 9-15, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28802410

RESUMO

The U.S. Centers for Disease Control and Prevention (CDC) uses a combination of spacer oligonucleotide typing (spoligotyping) and mycobacterial interspersed repetitive units-variable number of tandem repeats (MIRU-VNTR) analyses as part of the National TB Genotyping Service (NTGS). The NTGS expansion from 12-locus MIRU-VNTR (MIRU12) to 24-locus MIRU-VNTR (MIRU24) in 2009 enhanced the ability to discriminate Mycobacterium tuberculosis strains. In the current study, we investigated the MIRU24 concordance among epidemiologic-linked tuberculosis (TB) patients in four U.S. health jurisdictions. We also evaluated the programmatic benefits of combining MIRU24 and spoligotyping with epidemiologic evidence in identifying potential recent TB transmission. We examined 342 TB patients in 42 spoligotype/MIRU12 (PCRType) clusters (equivalent to 46 spoligotype/MIRU24 [GENType] clusters) to identify epidemiologic links among cases. GENType clusters, when compared to PCRType clusters, had 12 times higher odds of epidemiologic links being identified if patients were younger than 25 years and 3 times higher odds if patients resided in the same zip code, or had HIV infection. Sixty (18%) fewer PCRType-clustered patients would need investigations if clusters are defined using GENType instead of PCRType. An important advantage of defining clusters by MIRU24 is resource savings related to the reduced number of clustered cases needing investigation.


Assuntos
Técnicas Bacteriológicas , Loci Gênicos , Sequências Repetitivas Dispersas , Repetições Minissatélites , Técnicas de Diagnóstico Molecular , Mycobacterium tuberculosis/genética , Tuberculose/diagnóstico , Adulto , Análise por Conglomerados , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Mycobacterium tuberculosis/patogenicidade , Fenótipo , Valor Preditivo dos Testes , Tuberculose/epidemiologia , Tuberculose/microbiologia , Estados Unidos/epidemiologia , Adulto Jovem
4.
Open Forum Infect Dis ; 4(2): ofx034, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28730156

RESUMO

BACKGROUND: An elevated white blood cell (WBC) count is a characteristic finding in pneumococcal pneumonia. Very low WBC counts, occurring in some cases, are often associated with overwhelming pneumonia and have been attributed to alcohol-induced suppression of bone marrow. However, a systematic study of neutropenia, leukocytosis, alcohol ingestion, and cirrhosis in pneumococcal pneumonia has not been previously reported. METHODS: Using a database of patients with pneumococcal pneumonia at our medical center, we extracted data on WBC counts at admission, differential counts, alcohol ingestion, and cirrhosis, and we related these to 7-day and 30-day mortality. RESULTS: White blood cell counts were <6000/mm3 in 49 of 481 patients (10.2%) with pneumococcal pneumonia and >25000/mm3 in 40 (8.3%). Mortality at 7 days was 18.4% and 12.5%, respectively, 5-fold and 3-fold greater in patients with WBC <6000 or >25000 than in those with WBC counts between 6000 and 25000 (P < .001). Increased band forms were not associated with a worse outcome (P = .12). Alcohol use and cirrhosis were not associated with WBC counts <6000 (P = .63 and P = .41, respectively). CONCLUSIONS: In a large series of cases of pneumococcal pneumonia, WBC counts <6000 or >25000 correlated significantly with increased 7-day mortality. More than 10% band forms was not associated with a poor outcome. Alcohol abuse was not associated with low WBC or increased mortality. Our findings suggest that greater consideration be given to more intense care for patients with bacterial pneumonia who have very high or very low WBC counts at the time of hospital admission.

5.
Clin Transplant ; 31(8)2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28658512

RESUMO

BACKGROUND: The natural history of de novo donor-specific antibodies (dnDSA) after lung transplantation is not well-described. We sought to determine the incidence and risk factors associated with dnDSA and compare outcomes between recipients with transient (or isolated) vs persistent dnDSA after transplantation. METHODS: A single-center review of all lung transplants from 1/2009-7/2013. DSAs were tested eight times in the first year and every 4 months thereafter. Outcomes examined included acute rejection and graft failure. RESULTS: Median follow-up was 18 months (range: 1-61 months), and 24.6% of 333 first-time lung-only transplant recipients developed a dnDSA. Ethnicity, HLA-DQ mismatches, post-transplantation platelet transfusion and Lung Allocation Score >60 were associated with dnDSA (P<.05). Overall graft survival was worse for dnDSA-positive vs negative recipients (P=.025). Of 323 recipients with 1-year follow-up, 72 (22.2%) developed dnDSA, and in 25 (34.7%), the dnDSA was transient and cleared. Recipients with transient dnDSA were less likely to develop acute rejection than those with persistent dnDSA (P=.007). CONCLUSIONS: Early post-lung transplantation, dnDSA occurred in 1/4 of recipients, was associated with peri-transplant risk factors and resulted in decreased survival. Spontaneous clearance of dnDSA, seen in one-third of recipients, was associated with a lower risk of acute rejection.


Assuntos
Rejeição de Enxerto/imunologia , Sobrevivência de Enxerto/imunologia , Isoanticorpos/imunologia , Transplante de Pulmão , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Seguimentos , Rejeição de Enxerto/epidemiologia , Rejeição de Enxerto/terapia , Antígenos HLA/imunologia , Humanos , Estimativa de Kaplan-Meier , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Estudos Retrospectivos , Fatores de Risco , Doadores de Tecidos
6.
Pulm Circ ; 7(2): 399-408, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28597758

RESUMO

Pulmonary arterial hypertension (PAH) is a chronic progressive disease that leads to right heart failure and death. Pulmonary arterial capacitance (PAC), defined as stroke volume divided by the pulmonary pulse pressure, has been identified as a prognostic factor in PAH. The impact of changes in PAC over time, however, is unclear. We evaluated changes in PAC over time to determine if such changes predicted transplant-free survival. A single-center retrospective study of consecutive group 1 PAH patients who had two or more right heart catheterizations (RHC) between January 2007 and June 2016 was undertaken. Hemodynamic data, clinical data, and outcomes were collected. Univariate and multivariate Cox proportional-hazards modelling to identify the contribution of risk factors for a composite outcome of death or lung transplantation was done. Mixed-effects logistic regression was performed to investigate the association between the change in PAC value over time and the composite outcome. A P value < 0.05 was considered significant. In total, 109 consecutive patients with a total of 300 RHC data were identified. PAC correlated inversely with functional status ( P < 0.001) and inversely with pulmonary vascular resistance ( P < 0.001). PAC values increased with the addition of new PAH-specific medications. Mixed effects logistic regression modeling using longitudinal data showed that a decrease in PAC over the study period was associated with increased mortality and transplantation (adjusted P = 0.039) over the study period. Change in PAC was a better predictor of outcome over the study period than baseline PAC or changes in other hemodynamic or clinical parameters. Decreases in PAC were predictive of increased mortality or transplantation in patients with group 1 PAH. There was a trend towards increased PAC in response to the addition of a PAH-specific medication. Our data support the use of PAC as a therapeutic target in PAH.

7.
BMC Infect Dis ; 16(1): 594, 2016 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-27769182

RESUMO

BACKGROUND: Tracking the dissemination of specific Mycobacterium tuberculosis (Mtb) strains using genotyped Mtb isolates from tuberculosis patients is a routine public health practice in the United States. The present study proposes a standardized cluster investigation method to identify epidemiologic-linked patients in Mtb genotype clusters. The study also attempts to determine the proportion of epidemiologic-linked patients the proposed method would identify beyond the outcome of the conventional contact investigation. METHODS: The study population included Mtb culture positive patients from Georgia, Maryland, Massachusetts and Houston, Texas. Mtb isolates were genotyped by CDC's National TB Genotyping Service (NTGS) from January 2006 to October 2010. Mtb cluster investigations (CLIs) were conducted for patients whose isolates matched exactly by spoligotyping and 12-locus MIRU-VNTR. CLIs were carried out in four sequential steps: (1) Public Health Worker (PHW) Interview, (2) Contact Investigation (CI) Evaluation, (3) Public Health Records Review, and (4) CLI TB Patient Interviews. Comparison between patients whose links were identified through the study's CLI interviews (Step 4) and patients whose links were identified earlier in CLI (Steps 1-3) was conducted using logistic regression. RESULTS: Forty-four clusters were randomly selected from the four study sites (401 patients in total). Epidemiologic links were identified for 189/401 (47 %) study patients in a total of 201 linked patient-pairs. The numbers of linked patients identified in each CLI steps were: Step 1 - 105/401 (26.2 %), Step 2 - 15/388 (3.9 %), Step 3 - 41/281 (14.6 %), and Step 4 - 28/119 (30 %). Among the 189 linked patients, 28 (14.8 %) were not identified in previous CI. No epidemiologic links were identified in 13/44 (30 %) clusters. CONCLUSIONS: We validated a standardized and practical method to systematically identify epidemiologic links among patients in Mtb genotype clusters, which can be integrated into the TB control and prevention programs in public health settings. The CLI interview identified additional epidemiologic links that were not identified in previous CI. One-third of the clusters showed no epidemiologic links despite being extensively investigated, suggesting that some improvement in the interviewing methods is still needed.


Assuntos
Mycobacterium tuberculosis/genética , Tuberculose/epidemiologia , Tuberculose/microbiologia , Centers for Disease Control and Prevention, U.S. , Genótipo , Georgia/epidemiologia , Humanos , Modelos Logísticos , Maryland/epidemiologia , Massachusetts/epidemiologia , Repetições Minissatélites , Mycobacterium tuberculosis/isolamento & purificação , Texas/epidemiologia , Estados Unidos/epidemiologia
8.
Tuberculosis (Edinb) ; 101S: S109-S118, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27720377

RESUMO

BACKGROUND: There is an urgent need for methods that can rapidly and accurately assess therapeutic responses in patients with active tuberculosis (TB) in order to predict treatment outcomes. Exposure to bacterial pathogens can rapidly activate the plasma contact system, triggering the release of bradykinin (BK) and its metabolite desArg9-bradykinin (DABK) to induce inflammation and innate immune responses. We hypothesized that serum BK and DABK levels might act as sensitive immune response signatures for changes in Mycobacterium tuberculosis (Mtb) burden, and therefore examined how serum levels of these markers corresponded with anti-TB therapy in a small cohort of active TB cases. METHODS: Nanotrap Mass-Spectrometry (MS) was used to analyze serial blood specimens from 13 HIV-negative adults with microbiologically confirmed active TB who were treated with first-line anti-TB chemotherapy. MS signal for BK (m/z 1060.5) and DABK (m/z 904.5) serum peptides were evaluated at multiple time-points (before, during, and after treatment) to evaluate how BK and DABK levels corresponded with disease status. RESULTS: Serum BK levels declined from pretreatment baseline levels during the early stage anti-TB therapy (induction phase) and tended to remain below baseline levels during extended treatment (consolidation phase) and after therapy completion. BK levels were consistent with induction phase sputum culture conversions indicative of decreased Mtb burden reflecting good treatment responses. Serum DABK levels tended to increase during the induction phase and decrease at consolidation and post-therapy time points, which may indicate a shift from active disease to chronic inflammation to a disease free state. Elevated BK and DABK levels after treatment completion in one patient may be related to the subsequent recurrent TB disease. CONCLUSIONS: Our pilot data suggests that changes in the circulating BK and DABK levels in adult TB patients can be used as potential surrogate markers of the host response both early and late in anti-TB treatment for both pulmonary and extrapulmonary TB patients. We will further exploit these host-response signatures in the future as biomarkers in combination with other clinical and microbiologic tools which may improve treatment efficacy and facilitate the development of host-directed therapy.


Assuntos
Antituberculosos/uso terapêutico , Bradicinina/análogos & derivados , Tuberculose/tratamento farmacológico , Adulto , Biomarcadores/sangue , Bradicinina/sangue , Regulação para Baixo , Humanos , Pessoa de Meia-Idade , Mycobacterium tuberculosis/isolamento & purificação , Nanomedicina/métodos , Projetos Piloto , Valor Preditivo dos Testes , Recidiva , Indução de Remissão , Estudos Retrospectivos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Escarro/microbiologia , Fatores de Tempo , Resultado do Tratamento , Tuberculose/sangue , Tuberculose/diagnóstico , Tuberculose/microbiologia
9.
Ann Oncol ; 24(5): 1363-70, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23247660

RESUMO

BACKGROUND: The prognostic value of the NIH consensus criteria for graft-versus-host disease (GVHD) is not well defined yet. PATIENTS AND METHODS: We analyzed NIH-defined GVHD in 147 acute lymphoblastic leukemia (ALL) patients. RESULTS: The cumulative incidence of classic acute GVHD (aGVHD), late aGVHD and chronic GVHD (cGVHD) was 63%, 12% and 41%, respectively. cGVHD was subclassified as classic versus overlap syndrome in 40% versus 60% of cases. In multivariate Cox regression analysis with GVHD as time-dependent covariate, classic aGVHD grade III/IV had a negative impact on overall survival (OS) due to higher non-relapse mortality. cGVHD of any grade was associated with superior OS, which was due to lower relapse incidence. Classic cGVHD versus overlap syndrome had no differential impact. In 44 patients without GVHD after transplant who received donor lymphocyte infusions (DLI), the cumulative incidence of classic aGVHD, late aGVHD or cGVHD was 60%, 5% and 57%. Occurrence of cGVHD after DLI was associated with improved OS due to lower relapse incidence. CONCLUSIONS: The NIH consensus criteria for GVHD clearly define prognostic subgroups in patients transplanted for ALL. The improved OS in patients developing cGVHD after transplant or DLI gives clear evidence for a potent graft-versus-leukemia effect in this indication.


Assuntos
Doença Enxerto-Hospedeiro , Efeito Enxerto vs Leucemia , Transplante de Células-Tronco Hematopoéticas , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Adolescente , Adulto , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Condicionamento Pré-Transplante , Transplante Homólogo , Transplantes , Adulto Jovem
10.
Tuberc Res Treat ; 2012: 360852, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23227329

RESUMO

Background. Tuberculosis (TB) disease diagnosis in Vietnam relies on symptom screening, chest radiography (CXR), and acid fast bacilli (AFB) sputum smear which have a poor sensitivity in HIV patients. We evaluated the performance of clinical algorithms in screening and diagnosing AFB smear-negative TB in HIV patients. Methods. We enrolled 399 HIV-positive patients seeking care at a HIV clinic in Ho Chi Minh City (HCMC), Vietnam. Participants' demographics, medical history, common TB symptoms, CXR, and laboratory tests were collected. Results. Of 399 HIV patients, 390 had initial AFB-negative smears and 22/390 patients had positive cultures. Symptom screening missed 54% (12/22) of smear-negative pulmonary TB (PTB) cases. Multivariate analysis found CD4+ cell level and CXR were significant PTB predictors. An algorithm combining four TB symptoms and TST presented a high sensitivity (100%), but poorly specific (24%) diagnostic performance for smear-negative PTB. Conclusion. Up to 54% of PTB cases in the HIV-infected population may be missed in the routine screening and diagnostic procedures used in Vietnam. Symptom screening was a poor overall diagnostic measure in detecting smear-negative TB in HIV patients. Our study results suggest that routine sputum cultures should be implemented to achieve a more accurate diagnosis of TB in HIV patients.

11.
J Microbiol Biotechnol ; 17(10): 1585-90, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18156772

RESUMO

Although a number of melanogenesis inhibitors have recently been reported and used as cosmetic additives, none is completely satisfactory, leaving a need for novel skin-depigmenting agents. Thus, to develop a novel skin-depigmenting agent from natural sources, the inhibition of melanogenesis by Chinese plants was evaluated. A methanolic extract of Nigella glandulifera Freyn was found to inhibit the melanin synthesis of murine B16F10 melanoma cells by 43.7% and exhibited a low cytotoxicity (8.1 %) at a concentration of 100 microg/ml. Thus, to identify the melanogenesis-inhibiting mechanism, the inhibitory activity towards tyrosinase, the key enzyme of melanogenesis, was further evaluated, and the results showed inhibitory effects on the activity of intracellular tyrosinase yet not on mushroom tyrosinase. Finally, to isolate the compounds with a hypopigmenting capability, activity-guided isolation was performed, and Dioctyl phthalate identified as inhibiting melanogenesis.


Assuntos
Dietilexilftalato/farmacologia , Inibidores Enzimáticos/farmacologia , Melaninas/biossíntese , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Animais , Linhagem Celular Tumoral , Sobrevivência Celular , Melaninas/química , Melanoma Experimental , Camundongos , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/metabolismo , Nigella/química , Extratos Vegetais/química
12.
Int J Pharm ; 181(2): 159-72, 1999 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-10370212

RESUMO

MPOE-PLA microspheres containing bovine serum albumin (BSA) were prepared by the double emulsion method with high encapsulation efficiency ( approximately 93%). Confocal scanning microscopic analysis using MPOE-PLA labelled with 1-pyrenemethanol showed the MPOE coating of the microsphere surface. This coating improves the performance of the release system compared with PLA microspheres; the hydrophilic chains reduce the BSA adsorption onto the microspheres and increase the amount of BSA released in the supernatant. Microsphere analysis using atomic force microscopy showed that the presence of the MPOE chains also leads to surface roughness. Studies of the diffusion of 1% rhodamine aqueous solution into the microspheres by means of confocal microscopy showed a fast diffusion of water through the matrices containing high molecular weight MPOE chains (?10 000 g mol-1) and could explain the fast release of BSA from these microspheres.


Assuntos
Materiais Biocompatíveis/química , Ácido Láctico/química , Polietilenoglicóis/química , Polímeros/química , Soroalbumina Bovina/química , Adsorção , Preparações de Ação Retardada , Microanálise por Sonda Eletrônica , Fluoresceína-5-Isotiocianato/análogos & derivados , Fluoresceína-5-Isotiocianato/química , Microscopia Confocal , Microesferas , Tamanho da Partícula , Poliésteres , Água/química
13.
Biomaterials ; 16(1): 3-9, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7718689

RESUMO

The purpose of this study was to investigate lacrymal component accumulation on a soft contact lens (SCL) surface after various periods of continuous wear, using the recently developed atomic force microscopy (AFM). AFM allowed high resolution images of unworn and worn SCL, and presented two main advantages. 1. The SCL are analysed under nearly physiological conditions without being dried or destroyed. So the same SCL was analysed at various times during a long wearing period. To identify the deposited tear proteins, a qualitative analysis of solubilized deposit by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) on 4-15% gradient minigels was performed as well. We present typical images which emphasize the importance of the coating by lacrymal components. AFM analysis of worn SCL showed the deposition on the surface of a uniform lacrymal component coating (named deposit type I) with a progressive accumulation of numerous discrete granules (named deposit type II). SDS-PAGE of extracted deposits revealed the main tear proteins as: IgA, lactoferrin, tear lipocalin and lysozyme and the unknown protein of molecular weight 30,000. There is no clear difference in the protein patterns of the two types of deposits. Furthermore, a particular mode of use of AFM is described to illustrate the potential of this technique as a local tool for measuring protein coating thickness. Thus, for analysis of protein deposits on SCL surfaces, SDS-PAGE on minigels and AFM were easy and rapid to perform. When associated, these two techniques could find use in a wide range of worn SCL evaluation and most generally in biocompatibility evaluation studies.


Assuntos
Lentes de Contato Hidrofílicas/normas , Proteínas do Olho/análise , Lágrimas/química , Adulto , Proteínas de Transporte/análise , Proteínas de Transporte/química , Eletroforese em Gel de Poliacrilamida , Proteínas do Olho/química , Feminino , Humanos , Imunoglobulina A Secretora/análise , Imunoglobulina A Secretora/química , Lactoferrina/análise , Lactoferrina/química , Lipocalina 1 , Masculino , Microscopia de Força Atômica , Peso Molecular , Muramidase/análise , Muramidase/química , Proteínas e Peptídeos Salivares/análise , Proteínas e Peptídeos Salivares/química , Solubilidade
14.
Semin Thromb Hemost ; 20(2): 214-22, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7527938

RESUMO

PAF synthesized by or added to the endothelial cell monolayer has as first target the endothelium itself, inducing the expression of GMP-140 on the cell surface and qualitative alterations in the composition of glycocalyx. As seen by ESCA, sulfated chemical groups were significantly reduced after PAF stimulation. This reduction depended on selective loss of sulfated proteoglycans that were released into the supernatant. The alteration of glycocalyx may favor functional exposure of GMP-140 and of PAF on the surface of endothelial cells and may reduce charge repulsive forces between cells. PAF associated with endothelial cell surface has as second target PMNs and stimulates in cooperation with GMP-140, the functional activation of PMN CD11-CD18 adhesion molecules.


Assuntos
Moléculas de Adesão Celular/biossíntese , Endotélio Vascular/efeitos dos fármacos , Glicoproteínas/metabolismo , Fator de Ativação de Plaquetas/farmacologia , Polissacarídeos/metabolismo , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/farmacologia , Azepinas/farmacologia , Antígenos CD18/imunologia , Adesão Celular , Células Cultivadas , Cicloeximida/farmacologia , Microanálise por Sonda Eletrônica , Endotélio Vascular/metabolismo , Imunofluorescência , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Neutrófilos/citologia , Selectina-P , Fator de Ativação de Plaquetas/biossíntese , Glicoproteínas da Membrana de Plaquetas/biossíntese , Glicoproteínas da Membrana de Plaquetas/imunologia , Proteoglicanas/metabolismo , Triazóis/farmacologia , Veias Umbilicais
15.
J Cataract Refract Surg ; 19(3): 364-70, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8388951

RESUMO

The inflammatory cell response of tetrafluorocarbon (CF4) plasma surface modification of poly(methyl methacrylate) intraocular lenses (IOLs) was investigated in vitro. After two hours of lens contact with human granulocytes, scanning electron microscopy showed significantly less cell activation and granulocyte adhesion on the surface-modified IOL than on the untreated IOL (P < .01). The x-ray photo-electron spectroscopy analysis of the CF4 plasma surface modification demonstrated that new compounds containing fluorine were homogeneously grafted onto the PMMA lens surface, resulting in a marked increase of contact angle. These in vitro results must be confirmed by in vivo studies of CF4 plasma surface modification of IOLs.


Assuntos
Fluorocarbonos , Granulócitos/fisiologia , Lentes Intraoculares , Metilmetacrilatos , Materiais Biocompatíveis , Adesão Celular , Estudos de Avaliação como Assunto , Estudos de Viabilidade , Granulócitos/metabolismo , Humanos , Técnicas In Vitro , Metilmetacrilato , Poliestirenos , Superóxidos/metabolismo
16.
Biomaterials ; 14(4): 279-84, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8476997

RESUMO

Soft contact lens (SCL) surfaces were imaged with atomic force microscopy (AFM). High-resolution images of unworn SCL were obtained under nearly physiological medium. We present images of surfaces of collagen bandage lens under dry or aqueous conditions and of SCL of different water content and fabrication processes. Roughness parameters were determined. AFM studies of surfaces of SCL are expected to provide useful information on the hydrogel surfaces.


Assuntos
Lentes de Contato , Microscopia/métodos , Soluções Tampão , Colágeno , Metilmetacrilatos , Poli-Hidroxietil Metacrilato , Pirrolidinonas , Propriedades de Superfície
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