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1.
Appl Microbiol Biotechnol ; 101(10): 4009-4032, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28411325

RESUMO

Ginseng, an oriental gift to the world of healthcare and preventive medicine, is among the top ten medicinal herbs globally. The constitutive triterpene saponins, ginsenosides, or panaxosides are attributed to ginseng's miraculous efficacy towards anti-aging, rejuvenating, and immune-potentiating benefits. The major ginsenosides such as Rb1, Rb2, Rc, Rd., Re, and Rg1, formed after extensive glycosylations of the aglycone "dammaranediol," dominate the chemical profile of this genus in vivo and in vitro. Elicitations have successfully led to appreciable enhancements in the production of these major ginsenosides. However, current research on ginseng biotechnology has been focusing on the enrichment or production of the minor ginsenosides (the less glycosylated precursors of the major ginsenosides) in ginseng preparations, which are either absent or are produced in very low amounts in nature or via cell cultures. The minor ginsenosides under current scientific scrutiny include diol ginsenosides such as Rg3, Rh2, compound K, and triol ginsenosides Rg2 and Rh1, which are being touted as the next "anti-neoplastic pharmacophores," with better bioavailability and potency as compared to the major ginsenosides. This review aims at describing the strategies for ginsenoside production with special attention towards production of the minor ginsenosides from the major ginsenosides via microbial biotransformation, elicitations, and from heterologous expression systems.


Assuntos
Antineoplásicos/metabolismo , Bactérias/genética , Ginsenosídeos/biossíntese , Panax/metabolismo , Antineoplásicos/química , Bactérias/metabolismo , Biotransformação , Expressão Gênica , Ginsenosídeos/química , Ginsenosídeos/isolamento & purificação , Ginsenosídeos/uso terapêutico , Humanos , Panax/química , Panax/genética , Plantas Medicinais/química , Plantas Medicinais/genética
2.
Am J Transplant ; 16(1): 137-42, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26561981

RESUMO

Allocation policies for liver transplantation underwent significant changes in June 2013 with the introduction of Share 35. We aimed to examine the effect of Share 35 on regional variation in posttransplant outcomes. We examined two patient groups from the United Network for Organ Sharing dataset; a pre-Share 35 group composed of patients transplanted between June 17, 2012, and June 17, 2013 (n = 5523), and a post-Share group composed of patients transplanted between June 18, 2013, and June 18, 2014 (n = 5815). We used Kaplan-Meier and Cox multivariable analyses to compare survival. There were significant increases in allocation Model for End-stage Liver Disease (MELD) scores, laboratory MELD scores, and proportions of patients in the intensive care unit and on mechanical, ventilated, or organ-perfusion support at transplant post-Share 35. We also observed a significant increase in donor risk index in this group. We found no difference on a national level in survival between patients transplanted pre-Share 35 and post-Share 35 (p = 0.987). Regionally, however, posttransplantation survival was significantly worse in the post-Share 35 patients in regions 4 and 10 (p = 0.008 and p = 0.04), with no significant differences in the remaining regions. These results suggest that Share 35 has been associated with transplanting "sicker patients" with higher MELD scores, and although no difference in survival is observed on a national level, outcomes appear to be concerning in some regions.


Assuntos
Rejeição de Enxerto/prevenção & controle , Falência Hepática/cirurgia , Transplante de Fígado , Formulação de Políticas , Guias de Prática Clínica como Assunto/normas , Alocação de Recursos/métodos , Obtenção de Tecidos e Órgãos/normas , Feminino , Rejeição de Enxerto/epidemiologia , Sobrevivência de Enxerto , Humanos , Masculino , Pessoa de Meia-Idade , Doadores de Tecidos , Listas de Espera
3.
Am J Transplant ; 16(3): 1015-20, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26689853

RESUMO

The aim of this study was to determine the clinical and histologic outcomes related to transplanting kidneys from deceased donors with glomerular fibrin thrombi (GFT). We included all cases transplanted between October 2003 and October 2014 that had either a preimplantation biopsy or an immediate postreperfusion biopsy showing GFT. The study cohort included 61 recipients (9.9%) with GFT and 557 in the control group without GFT. Delayed graft function occurred in 49% of the GFT group and 39% in the control group (p = 0.14). Serum creatinine at 1, 4, and 12 months and estimated GFR at 12 months were similar in the two groups. Estimated 1-year graft survival was 93.2% in the GFT group and 95.1% in the control group (p = 0.22 by log-rank). Fifty-two of the 61 patients in the GFT group (85%) had a 1-month protocol biopsy, and only two biopsies (4%) showed residual focal glomerular thrombi. At the 1-year protocol biopsy, the prevalence of moderate to severe interstitial fibrosis and tubular atrophy was 24% in the GFT group and 30% in the control group (p = 0.42). We concluded that GFT resolves rapidly after transplantation and that transplanting selected kidneys from deceased donors with GFT is a safe practice.


Assuntos
Fibrina/análise , Rejeição de Enxerto/prevenção & controle , Falência Renal Crônica/cirurgia , Glomérulos Renais/patologia , Transplante de Rim , Trombose/patologia , Doadores de Tecidos/provisão & distribuição , Adulto , Cadáver , Feminino , Seguimentos , Taxa de Filtração Glomerular , Sobrevivência de Enxerto , Humanos , Testes de Função Renal , Glomérulos Renais/metabolismo , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Trombose/metabolismo
4.
Appl Microbiol Biotechnol ; 100(11): 4909-22, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26795963

RESUMO

Cobalt nitrate, nickel sulphate, hydrogen peroxide, sodium nitroprusside, and culture filtrates of Pseudomonas monteili, Bacillus circularans, Trichoderma atroviridae, and Trichoderma harzianum were tested to elicit ginsenoside production in a cell suspension line of Panax quinquefolius. Abiotic elicitors preferentially increased panaxadiols whereas biotic elicitors upregulated the panaxatriol synthesis. Cobalt nitrate (50 µM) increased total ginsenosides content by twofold (54.3 mg/L) within 5 days. It also induced the Rc synthesis that was absent in the control cultures. Elicitation with P. monteili (2.5 % v/v, 5 days) also supported 2.4-fold enhancement in saponin yield. Elicitation by T. atroviridae or hydrogen peroxide induced the synthesis of Rg3 and Rh2 that are absent in ginseng roots. The highest ginsenosides productivity (3.2-fold of control) was noticed in cells exposed to 1.25 % v/v dose of T. atroviridae for 5 days. Treating cells with T. harzianum for 15 days afforded maximum synthesis and leaching (8.1 mg/L) of ginsenoside Rh1.


Assuntos
Ginsenosídeos/biossíntese , Panax/química , Células Vegetais/efeitos dos fármacos , Bacillus/química , Cobalto/química , Meios de Cultura , Peróxido de Hidrogênio/química , Níquel/química , Nitroprussiato/química , Panax/citologia , Células Vegetais/metabolismo , Pseudomonas/química , Trichoderma/química
5.
Am J Transplant ; 11(7): 1435-43, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21718440

RESUMO

We sought to characterize sex-based differences in access to deceased donor liver transplantation. Scientific Registry of Transplant Recipients data were used to analyze n = 78 998 adult candidates listed before (8/1997-2/2002) or after (2/2002-2/2007) implementation of Model for End-Stage Liver Disease (MELD)-based liver allocation. The primary outcome was deceased donor liver transplantation. Cox regression was used to estimate covariate-adjusted differences in transplant rates by sex. Females represented 38% of listed patients in the pre-MELD era and 35% in the MELD era. Females had significantly lower covariate-adjusted transplant rates in the pre-MELD era (by 9%; p < 0.0001) and in the MELD era (by 14%; p < 0.0001). In the MELD era, the disparity in transplant rate for females increased as waiting list mortality risk increased, particularly for MELD scores ≥15. Substantial geographic variation in sex-based differences in transplant rates was observed. Some areas of the United States had more than a 30% lower covariate-adjusted transplant rate for females compared to males in the MELD era. In conclusion, the disparity in liver transplant rates between females and males has increased in the MELD era. It is especially troubling that the disparity is magnified among patients with high MELD scores and in certain regions of the United States.


Assuntos
Transplante de Fígado/estatística & dados numéricos , Adulto , Doença Hepática Terminal/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estados Unidos/epidemiologia , Listas de Espera
6.
Am J Transplant ; 10(4 Pt 2): 1069-80, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20420653

RESUMO

The effect of demand for kidney transplantation, measured by end-stage renal disease (ESRD) incidence, on access to transplantation is unknown. Using data from the U.S. Census Bureau, Centers for Medicare & Medicaid Services (CMS) and the Organ Procurement and Transplantation Network/Scientific Registry of Transplant Recipients (OPTN/SRTR) from 2000 to 2008, we performed donation service area (DSA) and patient-level regression analyses to assess the effect of ESRD incidence on access to the kidney waiting list and deceased donor kidney transplantation. In DSAs, ESRD incidence increased with greater density of high ESRD incidence racial groups (African Americans and Native Americans). Wait-list and transplant rates were relatively lower in high ESRD incidence DSAs, but wait-list rates were not drastically affected by ESRD incidence at the patient level. Compared to low ESRD areas, high ESRD areas were associated with lower adjusted transplant rates among all ESRD patients (RR 0.68, 95% CI 0.66-0.70). Patients living in medium and high ESRD areas had lower transplant rates from the waiting list compared to those in low ESRD areas (medium: RR 0.68, 95% CI 0.66-0.69; high: RR 0.63, 95% CI 0.61-0.65). Geographic variation in access to kidney transplant is in part mediated by local ESRD incidence, which has implications for allocation policy development.


Assuntos
Falência Renal Crônica/cirurgia , Transplante de Rim/estatística & dados numéricos , Doadores de Tecidos/estatística & dados numéricos , Obtenção de Tecidos e Órgãos/estatística & dados numéricos , Listas de Espera , Negro ou Afro-Americano/estatística & dados numéricos , Humanos , Incidência , Renda , Indígenas Norte-Americanos/estatística & dados numéricos , Falência Renal Crônica/economia , Transplante de Rim/economia , Medicaid/economia , Medicare/economia , Grupos Raciais , Sistema de Registros , Obtenção de Tecidos e Órgãos/economia , Estados Unidos
7.
Am J Transplant ; 10(11): 2512-9, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20977642

RESUMO

We aimed to identify recipient, donor and transplant risk factors associated with graft failure and patient mortality following donation after cardiac death (DCD) liver transplantation. These estimates were derived from Scientific Registry of Transplant Recipients data from all US liver-only DCD recipients between September 1, 2001 and April 30, 2009 (n = 1567) and Cox regression techniques. Three years post-DCD liver transplant, 64.9% of recipients were alive with functioning grafts, 13.6% required retransplant and 21.6% died. Significant recipient factors predictive of graft failure included: age ≥ 55 years, male sex, African-American race, HCV positivity, metabolic liver disorder, transplant MELD ≥ 35, hospitalization at transplant and the need for life support at transplant (all, p ≤ 0.05). Donor characteristics included age ≥ 50 years and weight >100 kg (all, p ≤ 0.005). Each hour increase in cold ischemia time (CIT) was associated with 6% higher graft failure rate (HR 1.06, p < 0.001). Donor warm ischemia time ≥ 35 min significantly increased graft failure rates (HR 1.84, p = 0.002). Recipient predictors of mortality were age ≥ 55 years, hospitalization at transplant and retransplantation (all, p ≤ 0.006). Donor weight >100 kg and CIT also increased patient mortality (all, p ≤ 0.035). These findings are useful for transplant surgeons creating DCD liver acceptance protocols.


Assuntos
Morte , Transplante de Fígado/efeitos adversos , Doadores de Tecidos , Adolescente , Adulto , Isquemia Fria , Feminino , Rejeição de Enxerto/epidemiologia , Humanos , Transplante de Fígado/mortalidade , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Obtenção de Tecidos e Órgãos/métodos , Resultado do Tratamento , Estados Unidos/epidemiologia , Isquemia Quente
8.
Water Sci Technol ; 62(12): 2920-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21123923

RESUMO

Present study deals with the biodegradation of p-cresol by using Pseudomonas putida in a batch reactor and a continuous bioreactor packed with calcium alginate beads. The maximum specific growth rate of 0.8121 h(-1) was obtained at 200 mg L(-1) concentration of p-cresol in batch reactor. The maximum p-cresol degradation rate was obtained 6.598 mg L(-1) h(-1) at S(o)=200 mg L(-1) and 62.8 mg L(-1) h(-1) at S(o)=500 mg L(-1) for batch reactor and a continuous bioreactor, respectively. The p-cresol degradation rate of continuous bioreactor was 9 to 10-fold higher than those of the batch reactor. It shows that the continuous bioreactor could tolerate a higher concentration of p-cresol. A Haldane model was also used for p-cresol inhibition in batch reactor and a modified equation similar to Haldane model for continuous bioreactor. The Haldane parameters were obtained as µ(max) 0.3398 h(-1), K(s) 110.9574 mg L(-1), and K(I) 497.6169 mg L(-1) in batch reactor. The parameters used in continuous bioreactor were obtained as D(max) 91.801 mg L(-1) h(-1), K(s) 131.292 mg L(-1), and K(I) 1217.7 mg L(-1). The value K(I) of continuous bioreactor is approximately 2.5 times higher than the batch reactor. Higher K(I) value of continuous bioreactor indicates P. putida can grow at high range of p-cresol concentration. The ability of tolerance of higher p-cresol concentrations may be one reason for biofilm attachment on the packed bed in the continuous operation.


Assuntos
Alginatos , Reatores Biológicos , Cresóis/metabolismo , Pseudomonas putida/metabolismo , Biodegradação Ambiental , Cresóis/química , Ácido Glucurônico , Ácidos Hexurônicos , Concentração de Íons de Hidrogênio , Cinética , Modelos Biológicos , Poluentes Químicos da Água/química , Poluentes Químicos da Água/metabolismo
9.
Am J Transplant ; 9(12): 2662-8, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20021478

RESUMO

Racial/ethnic disparities in access to and outcomes of liver transplantation are an important topic given the increasing diversity in the United States. Most reports on this topic predate the advent of allocation based on the model for end-stage liver disease (MELD). For many patients with a variety of lethal conditions, liver transplantation is the only effective therapy, signifying the importance of equitable access to care. Racial/ethnic disparities have been described at various steps of the liver transplant process, including liver disease prevalence and treatment, access to a transplant center and its waitlist, receipt of a liver transplant and posttransplant outcomes. The purpose of this minireview is to critically evaluate the published literature on racial/ethnicity-based disparities in liver disease prevalence and treatment, transplant center referral, transplant rates and posttransplant outcomes. We identify the shortcomings of previous reports and detail the barriers to completing properly constructed analyses, particularly emphasizing deficits in requisite data and the need for improved study design. Understanding the nature of race/ethnicity-based disparities in liver transplantation is necessary to improve research initiatives, policy design and serves the broader responsibility of providing the highest quality care to all patients with liver disease.


Assuntos
Disparidades em Assistência à Saúde , Falência Hepática/etnologia , Transplante de Fígado/etnologia , Grupos Raciais , Negro ou Afro-Americano , Povo Asiático , Etnicidade , Hispânico ou Latino , Humanos , Projetos de Pesquisa , Obtenção de Tecidos e Órgãos , Resultado do Tratamento , Estados Unidos , Listas de Espera
10.
Am J Transplant ; 9(10): 2416-23, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19656129

RESUMO

Travel to procure deceased donor organs is associated with risk to transplant personnel. In many instances, multiple teams are present for a given operation. We studied our statewide experience to determine how much excess travel this redundancy entails, and generated alternate models for organ recovery. We reviewed our organ procurement organization's experience with deceased donor operations between 2002 and 2008. Travel was expressed as cumulative person-miles between procurement team origin and donor hospital. A model of minimal travel was created, using thoracic and abdominal teams from the closest in-state center. A second model involved transporting donors to a dedicated procurement facility. Travel distance was recalculated using these models, and mode and cost of travel extrapolated from current practices. In 654 thoracic and 1469 abdominal donors studied, the mean travel for thoracic teams was 1066 person-miles and for abdominal teams was 550 person-miles. The mean distance traveled by thoracic and abdominal organs was 223 miles and 142 miles, respectively. Both hypothetical models showed reductions in team travel and reliance on air transport, with favorable costs and organ transport times compared to historical data. In summary, we found significant inefficiency in current practice, which may be alleviated using new paradigms for donor procurement.


Assuntos
Obtenção de Tecidos e Órgãos/normas , Humanos , Michigan , Doadores de Tecidos
12.
Protoplasma ; 255(4): 1147-1160, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29450757

RESUMO

Dual metabolite, i.e., ginsenoside and anthocyanin, co-accumulating cell suspensions of Panax sikkimensis were subjected to elicitation with culture filtrates of Serratia marcescens (SD 21), Bacillus subtilis (FL11), Trichoderma atroviridae (TA), and T. harzianum (TH) at 1.25% and 2.5% v/v for 1- and 3-week duration. The fungal-derived elicitors (TA and TH) did not significantly affect biomass accumulation; however, bacterial elicitors (SD 21 and FL11), especially SD 21, led to comparable loss in biomass growth. In terms of ginsenoside content, differential responses were observed. A maximum of 3.2-fold increase (222.2 mg/L) in total ginsenoside content was observed with the use of 2.5% v/v TH culture filtrate for 1 week. Similar ginsenoside accumulation was observed with the use of 1-week treatment with 2.5% v/v SD 21 culture filtrate (189.3 mg/L) with a 10-fold increase in intracellular Rg2 biosynthesis (31 mg/L). Real-time PCR analysis of key ginsenoside biosynthesis genes, i.e., FPS, SQS, DDS, PPDS, and PPTS, revealed prominent upregulation of particularly PPTS expression (20-23-fold), accounting for the observed enhancement in protopanaxatriol ginsenosides. However, none of the elicitors led to successful enhancement in in vitro anthocyanin accumulation as compared to control values.


Assuntos
Ginsenosídeos/genética , Ginsenosídeos/metabolismo , Panax/química , Raízes de Plantas/química , Meios de Cultura , Suspensões
13.
Sci Total Environ ; 599-600: 165-180, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28475910

RESUMO

Long-term measurements of spectral aerosol optical depth (AOD) using sun/sky radiometer for a period of five years (2009-2014) from the remote island location at Kavaratti (KVT; 10.56°N, 72.64°E) in the southern Arabian sea have been analysed. Climatologically, AODs decrease from October to reach maximum of ~0.6 (at 500nm) in March, followed by a sudden fall towards May. Significant modulations of intra-seasonal timescales over this general pattern are noticed due to the changes in the relative strength of distinctively different sources. The corresponding changes in aerosol inversion parameters reveal the presence of coarse-mode aerosols during spring and fine-mode absorbing aerosols in autumn and winter months. An overall dominance of a mixed type of aerosols (~41%) with maximum in winter (~53%) was found via the AOD500 vs. Ångström exponent (α440-870) relationship, while biomass-burning aerosols or thick urban/industrial plumes contribute to ~19%. Spectral dependence of Ångström exponent and aerosol absorbing properties were used to identify the aerosol types and its modification processes. Based on air mass back trajectory analysis, we revealed that the advection of aerosols from Indian subcontinent and western regions plays a major role in modifying the optical properties of aerosols over the observational site. The shortwave aerosol direct radiative forcing estimated via SBDART model ranges from -11.00Wm-2 to -7.38Wm-2, -21.51Wm-2 to -14.33Wm-2 and 3.17Wm-2 and 10.0Wm-2 at top of atmosphere, surface and within the atmosphere, respectively. This atmospheric forcing translates into heating rate of 0.62-1.04Kday-1. Furthermore, the vertical profiles of aerosols and heating rate exhibit significant increase in lower (during winter and autumn) and mid troposphere (during spring). This may cause serious climate implications over Kavaratti with further consequences on cloud microphysics and monsoon rainfall.

14.
Transplant Proc ; 48(6): 1986-92, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27569933

RESUMO

BACKGROUND: Currently, transplant patients have limited metrics available to understand transplant center quality. Graft and patient survival do not capture the patient experience, and patients may use more general consumer assessments of hospital care to help select transplant centers. We evaluated whether consumer assessments of hospital quality correlate with short- and long-term kidney transplant center performance. MATERIALS AND METHODS: CMS uses the Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) to publicly report patients' perspectives on hospital care. We merged 2012 SRTR kidney transplant (n = 200 centers), HCAHPS and American Hospital Association survey data. Center performance was determined by variation in observed-to-expected (O/E) ratios for 1-month and 1-year graft failure. We used multivariate regression to determine whether HCAHPS measures correlate with center performance, after risk-adjusting for structural characteristics and volume. RESULTS: Center-specific graft failure varied significantly (30 day O/E range: 0-4.1). At 30 days, compared to average centers, cleanliness (OR = 1.26, P = .001), patient recommendation (OR = 1.18, P = .005), and high overall ratings (OR = 1.11, P = .036) predicted high performance. Poor nursing-patient communication (OR = 0.70, P = .030), lower cleanliness (OR = 0.67, P < .001), poor overall ratings (OR = 0.79, P = .038), and no recommendation (OR = 0.68, P = .019) correlated with average/low performance. There was no significant correlation between HCAHPS measures and 1-year outcomes. CONCLUSIONS: The association between hospital consumer assessments of hospital care and center performance after kidney transplantation is limited. More specific metrics oriented to capturing transplant patient perspectives may be valuable in further defining transplant quality.


Assuntos
Hospitalização , Transplante de Rim , Avaliação de Resultados da Assistência ao Paciente , Satisfação do Paciente , Comunicação , Estudos Transversais , Humanos , Reprodutibilidade dos Testes , Risco Ajustado , Estados Unidos
15.
Diabetes ; 42(9): 1324-32, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8349044

RESUMO

Plasma glucose values after oral glucose challenge vary widely in nondiabetic subjects. We have now evaluated the role of insulin resistance in determining the plasma glucose response to oral glucose in 74 volunteer subjects with normal glucose tolerance. In these subjects, we determined the plasma glucose and insulin responses over a 3-h period to a 75-g oral glucose challenge, and the steady-state plasma glucose concentration during a continuous infusion of somatostatin, glucose, and insulin (a quantitative measure of insulin resistance). The plasma glucose response was defined as the incremental increase in plasma glucose concentration above the fasting value for 3 h after the oral glucose challenge. Multiple regression analysis was used to define the relationship between the dependent variable (plasma glucose response) and various predictors of this response. These analyses indicated that both the steady-state plasma glucose and the incremental insulin response during the first 30 min after the glucose load were significant predictors of the plasma glucose response. In those individuals in whom insulin action was impaired and the 30-min plasma insulin response was decreased, plasma glucose values reached higher levels. When standardized regression coefficients were determined, the incremental glucose response was directly correlated with steady-state plasma glucose (r = 0.700, P < 0.001) and inversely with the insulin response during the first 30 min (r = 0.268, P = 0.023). Furthermore, the correlation between steady-state plasma glucose and glucose response was significantly greater (P < 0.005) than that between the glucose response and 30-min insulin concentration.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Glicemia/metabolismo , Resistência à Insulina/fisiologia , Insulina/metabolismo , Adulto , Idoso , Feminino , Teste de Tolerância a Glucose , Humanos , Insulina/fisiologia , Secreção de Insulina , Masculino , Pessoa de Meia-Idade , Valores de Referência , Análise de Regressão , Fatores de Tempo
16.
Biomed Environ Sci ; 18(4): 238-40, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16274105

RESUMO

OBJECTIVE: To study the effects of paraphenylenediamine (PPD) and linear alkylbenzene sulphonate (LAS) alone and in combination on the skin. METHODS: Forty-eight guinea pigs were divided equally into 4 groups and exposed to PPD (4 mg/kg), LAS (12 mg/kg) and PPD (4 mg/kg) plus LAS (12 mg/kg) for 30 days. The biochemical parameters such as acid phosphatase, gtutathione-s-transferase, glutathione peroxidase, glutathione, lipid peroxidation and histamine contents in exposed skin were estimated. The histopathological examination of the exposed skin was also carried out. RESULTS: The skin enzymes, lipid peroxidation, and histamine increased while glutathione decreased in skin. The simultaneously exposed group showed additive toxic effects. The histopathological examination showed severe hyperkeratosis, thickening of collagen fibres and vacuolisation of epidermal cells in PPD plus LAS exposed skin. CONCLUSION: The findings of the present study suggest that simultaneous exposure to PPD and LAS has additive toxic effects.


Assuntos
Ácidos Alcanossulfônicos/toxicidade , Corantes/toxicidade , Fenilenodiaminas/toxicidade , Pele/efeitos dos fármacos , Tensoativos/toxicidade , Fosfatase Ácida/biossíntese , Animais , Sinergismo Farmacológico , Glucuronidase/biossíntese , Glutationa/metabolismo , Glutationa Peroxidase/biossíntese , Glutationa Transferase/biossíntese , Cobaias , Histamina/biossíntese , Peroxidação de Lipídeos , Masculino , Pele/enzimologia , Pele/patologia
17.
J Bone Miner Res ; 11(5): 626-37, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-9157777

RESUMO

Dual X-ray absorptiometry (DXA) is widely used to monitor treatment efficacy in reducing the rate of bone mineral loss. In order to assure the validity of these measurements, instrument quality control of the DXA scanners becomes very important. This paper compares five quality control procedures (visual inspection, Shewhart chart with sensitizing rules, Shewhart chart with sensitizing rules and a filter for clinically insignificant mean changes, moving average chart and standard deviation, and cumulative sum chart [CUSUM]) in their ability to identify scanner malfunction by means of (1) an analysis of five longitudinal phantom data sets that had been collected during a clinical trial and (2) an analysis of simulated data sets. The visual inspection method is relatively subjective and depends on the operator's experience and attention. The regular Shewhart chart with sensitizing rules has a high false alarm rate. The Shewhart chart with sensitizing rules and an additional filter for clinically insignificant mean changes has the lowest false alarm rate but a relatively low sensitivity. The CUSUM method has good sensitivity and a low false alarm rate. In addition, this method provides an estimate of the date a change in the DXA scanner performance might have occurred. The method combining a moving average chart and a moving standard deviation chart came closest to the performance of the CUSUM method. Comparing the advantages and disadvantages of all methods, we propose the use of the CUSUM method as a quality control procedure for monitoring DXA scanner performance. For clinical trials use of the more intuitive Shewhart charts may be acceptable at the individual sites provided their scanner performance is followed up by CUSUM analysis at a central quality assurance center.


Assuntos
Absorciometria de Fóton/métodos , Densidade Óssea , Absorciometria de Fóton/normas , Humanos , Padrões de Referência
18.
Semin Arthritis Rheum ; 23(6 Suppl 2): 3-10, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7939728

RESUMO

This report reviews and discusses studies on the synovial fluid and biopsy specimens of synovial membrane obtained during the first 6 weeks of synovitis that evolved into rheumatoid arthritis (RA). Five previously unreported cases are described. Early changes in the microvasculature and synovial lining seem to antedate the classical chronic inflammation of established RA. Further characterization in the joint tissues in very early RA offers opportunities for identification of exogenous triggers and may allow more appropriate targeting of early therapy to potentially reversible aspects of pathogenesis.


Assuntos
Artrite Reumatoide/patologia , Membrana Sinovial/patologia , Adulto , Endotélio Vascular/ultraestrutura , Feminino , Humanos , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Líquido Sinovial/citologia , Membrana Sinovial/irrigação sanguínea , Membrana Sinovial/ultraestrutura , Sinovite/patologia
19.
Toxicology ; 8(1): 53-61, 1977 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-929618

RESUMO

Toxicity of trivalent and hexavalent chromium compounds was investigated in experimental rabbits to ascertain health hazards among industrial workers of miners occupationally exposed to such chemicals. Brain, kidney and myocardium showed a tendency to accumulate chromium irrespective of its valency state; the morphological changes were more marked in animals exposed to hexavalent chromium. However, no definite co-relation could be observed between the concentration of the metal and the degree of histological changes in these organs.


Assuntos
Cromo/toxicidade , Animais , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/patologia , Coração/efeitos dos fármacos , Rim/efeitos dos fármacos , Rim/patologia , Miocárdio/patologia , Especificidade de Órgãos , Coelhos , Relação Estrutura-Atividade
20.
Toxicology ; 10(2): 105-13, 1978 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-684755

RESUMO

The effect of dose and duration of exposure on the relative distribution of nickel in the vital organs and bone of albino rats was investigated. The rate of accumulation of the metal, in general, was highest in myocardium and spleen followed by kidney, bone and other tissues. The sub-cellular fractionation of myocardium revealed higher metal localization in nuclear and mitochondrial fractions than in the microsomal and cytosolic fractions. However, the uptake of metal by various tissues and its sub-cellular distribution was regulated by the dose and duration of exposure. No significant chromosomal damage was observed in either the bone marrow or the spermatogonial cells in the animals during early nickel intoxication.


Assuntos
Cromossomos/efeitos dos fármacos , Níquel/metabolismo , Animais , Masculino , Miocárdio/ultraestrutura , Níquel/intoxicação , Ratos , Frações Subcelulares/efeitos dos fármacos , Fatores de Tempo , Distribuição Tecidual
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