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1.
BMC Vet Res ; 13(1): 347, 2017 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-29166903

RESUMO

BACKGROUND: Circulating miRNAs (ci-miRNAs) are endogenous, non-coding RNAs emerging as potential diagnostic biomarkers. Equine miRNAs have been previously identified including subsets of tissue-specific miRNAs. In order to investigate ci-miRNAs as diagnostic tools, normal patterns of expression for different scenarios including responses to exercise need to be identified. Human studies have demonstrated that many ci-miRNAs are up-regulated following exercise with changes in expression patterns in skeletal muscle. However, technical challenges such as haemolysis impact on accurate plasma ci-miRNA quantification, with haemolysis often occurring naturally in horses following moderate-to-intense exercise. The objectives of this study were to identify plasma ci-miRNA profiles and skeletal muscle miRNAs before and after exercise in Thoroughbreds (Tb), and to evaluate for the presence and effect of haemolysis on plasma ci-miRNA determination. Resting and post-exercise plasma ci-miRNA profiles and haemolysis were evaluated in twenty 3 year-old Tbs in sprint training. Resting and post-exercise skeletal muscle miRNA abundance was evaluated in a second cohort of eleven 2 year-old Tbs just entering sprint training. Haemolysis was further quantified in resting blood samples from twelve Tbs in sprint training. A human plasma panel containing 179 miRNAs was used for profiling, with haemolysis assessed spectrophotometrically. Data was analysed using a paired Student's t-test and Pearson's rank correlation. RESULTS: Plasma ci-miRNA data for 13/20 horses and all skeletal muscle miRNA data passed quality control. From plasma, 52/179 miRNAs were detected at both time-points. Haemolysis levels were greater than the threshold for accurate quantification of ci-miRNAs in 18/25 resting and all post-exercise plasma samples. Positive correlations (P < 0.05) between haemolysis and miRNA abundance were detected for all but 4 miRNAs, so exercise-induced changes in plasma ci-miRNA expression could not be quantified. In skeletal muscle samples, 97/179 miRNAs were detected with 5 miRNAs (miR-21-5p, let-7d-3p, let-7d-5p, miR-30b-5p, miR-30e-5p) differentially expressed (DE, P < 0.05) between time-points. CONCLUSIONS: The degree of haemolysis needs to be determined prior to quantifying plasma ci-miRNA expression from horses in high-intensity exercise training. Identification of DE miRNAs in skeletal muscle indicates modification of miRNA expression may contribute to adaptive training responses in Tbs. Using a human plasma panel likely limited detection of equine-specific miRNAs.


Assuntos
Cavalos/metabolismo , MicroRNAs/metabolismo , Músculo Esquelético/metabolismo , Condicionamento Físico Animal/fisiologia , Animais , Feminino , Hemólise/fisiologia , Cavalos/sangue , Masculino , MicroRNAs/sangue , Descanso/fisiologia
2.
J Clin Invest ; 103(2): 253-9, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9916137

RESUMO

To examine the mechanism by which free fatty acids (FFA) induce insulin resistance in human skeletal muscle, glycogen, glucose-6-phosphate, and intracellular glucose concentrations were measured using carbon-13 and phosphorous-31 nuclear magnetic resonance spectroscopy in seven healthy subjects before and after a hyperinsulinemic-euglycemic clamp following a five-hour infusion of either lipid/heparin or glycerol/heparin. IRS-1-associated phosphatidylinositol 3-kinase (PI 3-kinase) activity was also measured in muscle biopsy samples obtained from seven additional subjects before and after an identical protocol. Rates of insulin stimulated whole-body glucose uptake. Glucose oxidation and muscle glycogen synthesis were 50%-60% lower following the lipid infusion compared with the glycerol infusion and were associated with a approximately 90% decrease in the increment in intramuscular glucose-6-phosphate concentration, implying diminished glucose transport or phosphorylation activity. To distinguish between these two possibilities, intracellular glucose concentration was measured and found to be significantly lower in the lipid infusion studies, implying that glucose transport is the rate-controlling step. Insulin stimulation, during the glycerol infusion, resulted in a fourfold increase in PI 3-kinase activity over basal that was abolished during the lipid infusion. Taken together, these data suggest that increased concentrations of plasma FFA induce insulin resistance in humans through inhibition of glucose transport activity; this may be a consequence of decreased IRS-1-associated PI 3-kinase activity.


Assuntos
Ácidos Graxos não Esterificados/farmacologia , Glucose/metabolismo , Músculo Esquelético/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fosfoproteínas/metabolismo , Adolescente , Adulto , Ácidos Graxos não Esterificados/sangue , Feminino , Técnica Clamp de Glucose , Glucose-6-Fosfato/metabolismo , Glicerol/metabolismo , Glicogênio/metabolismo , Humanos , Hiperinsulinismo/metabolismo , Insulina/sangue , Proteínas Substratos do Receptor de Insulina , Resistência à Insulina , Metabolismo dos Lipídeos , Espectroscopia de Ressonância Magnética , Masculino , Músculo Esquelético/enzimologia
3.
Diabetes ; 48(6): 1270-4, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10342815

RESUMO

To examine the mechanism by which free fatty acids (FFAs) induce insulin resistance in vivo, awake chronically catheterized rats underwent a hyperinsulinemic-euglycemic clamp with or without a 5-h preinfusion of lipid/heparin to raise plasma FFA concentrations. Increased plasma FFAs resulted in insulin resistance as reflected by a approximately 35% reduction in the glucose infusion rate (P < 0.05 vs. control). The insulin resistance was associated with a 40-50% reduction in 13C nuclear magnetic resonance (NMR)-determined rates of muscle glycogen synthesis (P < 0.01 vs. control) and muscle glucose oxidation (P < 0.01 vs. control), which in turn could be attributed to a approximately 25% reduction in glucose transport activity as assessed by 2-[1,2-3H]deoxyglucose uptake in vivo (P < 0.05 vs. control). This lipid-induced decrease in insulin-stimulated muscle glucose metabolism was associated with 1) a approximately 50% reduction in insulin-stimulated insulin receptor substrate (IRS)-1-associated phosphatidylinositol (PI) 3-kinase activity (P < 0.05 vs. control), 2) a blunting in insulin-stimulated IRS-1 tyrosine phosphorylation (P < 0.05, lipid-infused versus glycerol-infused), and 3) a four-fold increase in membrane-bound, or active, protein kinase C (PKC) theta (P < 0.05 vs. control). We conclude that acute elevations of plasma FFA levels for 5 h induce skeletal muscle insulin resistance in vivo via a reduction in insulin-stimulated muscle glycogen synthesis and glucose oxidation that can be attributed to reduced glucose transport activity. These changes are associated with abnormalities in the insulin signaling cascade and may be mediated by FFA activation of PKC theta.


Assuntos
Ácidos Graxos não Esterificados/sangue , Resistência à Insulina , Insulina/fisiologia , Isoenzimas/metabolismo , Proteína Quinase C/metabolismo , Transdução de Sinais , Dedos de Zinco , Animais , Desoxiglucose/metabolismo , Ativação Enzimática , Proteínas Substratos do Receptor de Insulina , Espectroscopia de Ressonância Magnética , Masculino , Músculo Esquelético/enzimologia , Fosfatidilinositol 3-Quinases/metabolismo , Fosfoproteínas/metabolismo , Fosforilação , Proteína Quinase C-theta , Ratos , Ratos Sprague-Dawley , Tirosina/metabolismo
4.
QJM ; 89(3): 211-6, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8731565

RESUMO

Alterations in low-density lipoprotein (LDL) composition in diabetes affect its function with respect to control of de novo cholesterol synthesis. We examined the effect of 4 weeks of an oleic-acid-rich diet on LDL composition and function in eight Type 2 diabetic and eight non-diabetic control subjects. LDL (density 1.019-1.063 g/l) was isolated by sequential ultracentrifugation. LDL composition was measured and LDL fatty acids were determined by gas liquid chromatography. Cholesterol synthesis was measured by [14C]-acetate incorporation into the freshly isolated mononuclear leucocytes. Fasting blood glucose fell from 9.3 +/- 2.0 to 8.2 +/- 1.2 mmol/l (p < 0.05) and fasting serum insulin increased from 8.3 +/- 2.8 to 10.4 +/- 5.0 mIU/l (p > 0.05) in the diabetic patients. LDL oleic acid increased in the diabetic patients from 18.8 +/- 1.8% to 22.5 +/- 1.9% (p < 0.01) and in the non-diabetic subjects from 19.9 +/- 1.8% to 23.3 +/- 2.8% (p < 0.01). The LDL-esterified to free cholesterol ratios of 3.0 +/- 0.6 and 2.7 +/- 0.2 for the diabetic and non-diabetic patients were similar, and decreased significantly (p < 0.01) to 2.4 +/- 0.5 and 2.2 +/- 0.4, respectively. Baseline [14C]-acetate incorporation was similar in the two groups, and decreased after diet from 437 +/- 239 to 249 +/- 144 ng/g cell protein (p < 0.05) in the diabetic patients. There was a negative correlation between the LDL-esterified to free cholesterol ratio and the ratio of oleic to linoleic acid in the LDL (r = -0.39, p < 0.05) and a negative correlation between fasting blood glucose and LDL oleic acid in the diabetic patients (r = -0.51, p < 0.05). Enrichment of LDL with oleic acid appears to improve its ability to regulate endogenous cholesterol synthesis in both control and diabetic subjects. In the diabetic population, the diet had a favourable effect on glycaemic control.


Assuntos
Arteriosclerose/prevenção & controle , Diabetes Mellitus Tipo 2/sangue , Lipoproteínas LDL/química , Ácidos Oleicos/administração & dosagem , Acetatos/metabolismo , Adulto , Ácido Araquidônico/metabolismo , Glicemia/metabolismo , Colesterol/metabolismo , Jejum , Feminino , Humanos , Ácido Linoleico , Ácidos Linoleicos/análise , Ácidos Linoleicos/metabolismo , Lipoproteínas LDL/metabolismo , Masculino , Pessoa de Meia-Idade , Ácido Oleico , Ácidos Oleicos/análise , Ácidos Oleicos/sangue
5.
Brain Res Dev Brain Res ; 120(1): 7-16, 2000 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-10727725

RESUMO

CYP26 (P450RAI) catalyzes catabolic retinoic acid (RA) hydroxylation and thereby appears to play a critical role in retinoid signaling pathways during development. In this study, a quantitative competitive reverse transcriptase-polymerase chain reaction (RT-PCR) assay was developed for evaluation of CYP26 message levels in human prenatal tissues. Statistical analyses of transcription levels in 12 prenatal human brains and six prenatal human livers demonstrated good sensitivity and reproducibility. Quantitative profiles of CYP26 gene expression in early (gestational days 57-110) prenatal cephalic and hepatic tissues and comparisons with adult counterparts are reported for the first time. Prenatal cephalic tissues at days 57-67 exhibited values of 1950+/-420 (CYP26 molecules/10(6) GAPDH molecules) whereas prenatal cephalic tissues at days 105-110 exhibited values of 22300+/-4450 (CYP26 molecules/10(6) GAPDH molecules), indicating a sharp developmental increase (approximately 11-fold). Levels in human adult cephalic tissues were slightly less than the prenatal cephalic levels measured during the earliest stages of gestation and were approximately 3-fold lower than those measured in adult human hepatic tissues. Levels in human prenatal hepatic tissues at days 63-110 gestation were less than 800 (CYP26 molecules/10(6) GAPDH molecules) and did not exhibit developmental increases. Considered together, the data have strong implications for the importance of CYP26 in early development of the human brain.


Assuntos
Encéfalo/embriologia , Sistema Enzimático do Citocromo P-450/genética , Regulação da Expressão Gênica no Desenvolvimento , Fígado/embriologia , Adulto , Fatores Etários , Encéfalo/enzimologia , Primers do DNA , Feto/enzimologia , Regulação Enzimológica da Expressão Gênica , Gliceraldeído-3-Fosfato Desidrogenases/genética , Humanos , Fígado/enzimologia , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/análise , Ácido Retinoico 4 Hidroxilase , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/fisiologia , Transcrição Gênica/fisiologia
6.
Ir J Med Sci ; 166(4): 260-2, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9394080

RESUMO

Secondary failure of oral hypoglycaemic agents raises the dilemma of whether to institute therapy with insulin alone, or in combination. We reviewed our experience of combination therapy following secondary failure of oral hypoglycaemic therapy. Seventeen subjects were receiving combination therapy for 6 months or more. Such treatment was associated with a significant fall in HbA1C--from 10.7 +/- 0.38 per cent to 8.3 +/- 0.35 per cent (p < 0.01) after 6 months and remained significantly reduced at 12 months (8.7 +/- 0.34 per cent (p < 0.01)). Mean body weight, systolic and diastolic blood pressure were unchanged during treatment with adjuvant insulin therapy. Insulin therapy is a useful adjunct in the daily management of subjects with NIDDM who experience secondary failure of oral hypoglycaemic agents.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Idoso , Diabetes Mellitus Tipo 2/sangue , Relação Dose-Resposta a Droga , Esquema de Medicação , Quimioterapia Combinada , Feminino , Seguimentos , Hemoglobinas Glicadas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
11.
J Nutr ; 122(6): 1332-7, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1588450

RESUMO

Two experiments were conducted to determine the dietary lysine requirement of juvenile hybrid striped bass (Morone saxatilis x M. chrysops). In both experiments the diets contained 35 g crude protein/100 g diet (10 g crude protein supplied by casein and gelatin and 25 g crude protein supplied by crystalline L-amino acids) and contained graded levels of L-lysine.HCl resulting in eight dietary treatments. Diets were fed to triplicate groups of fish and ranged in dietary lysine concentration from 1.2 to 2.6 g/100 g of the dry diet in Experiment 1 and from 0.8 to 2.2 g/100 g of the dry diet in Experiment 2. Weight gain and food efficiency data from Experiment 1 indicated the dietary lysine requirement to be between 1.2 and 1.4 g/100 g of the dry diet. Weight gain, food efficiency and serum lysine data from Experiment 2 confirmed the requirement to be between 1.2 and 1.4 g/100 g of the dry diet. Broken-line analysis of weight gain and food efficiency data from Experiment 2 indicated the dietary lysine requirement to be 1.4 +/- 0.2% of the dry diet, or 4.0 g/100 g of the dietary protein. Changes in the relative proportions of dietary lipid and carbohydrate between the two experiments, although maintaining similar gross energy levels, did not alter the lysine requirement estimate of juvenile hybrid striped bass.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Bass/fisiologia , Proteínas Alimentares/administração & dosagem , Lisina/administração & dosagem , Animais , Lisina/sangue , Necessidades Nutricionais , Aumento de Peso
12.
J Nutr ; 124(6): 888-93, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8207547

RESUMO

Two experiments were conducted to determine the dietary arginine requirement of juvenile hybrid striped bass (Morone saxatilis x M. chrysops); a third experiment evaluated the interaction of lysine and arginine. Diets in Experiments 1 and 2 were supplemented with graded concentrations of L-arginine-HCl, resulting in eight dietary treatments. Dietary arginine concentrations ranged from 1.0 to 2.4 g/100 g diet in Experiment 1 and from 0.6 to 2.0 g/100 g diet in Experiment 2. Weight gain was not affected by dietary treatments in Experiment 1. Feed efficiency was significantly affected by dietary arginine concentrations, and the data, when subjected to broken-line analysis, resulted in a requirement estimate of 1.53 +/- 0.20 g/100 g diet. Weight gain and feed efficiency were both significantly affected by dietary arginine concentrations in Experiment 2. Broken-line analyses of weight gain and feed efficiency data indicated the dietary arginine requirement to be 1.55 +/- 0.10 and 1.45 +/- 0.12 g/100 g diet, respectively. Diets in Experiment 3 contained lysine and arginine in ratios of 1:1, 1:1.5, 1:2 and 1:2.5 for the previously estimated requirements for both lysine:arginine and arginine:lysine. No differences were observed in weight gain or feed efficiency for fish fed various lysine:arginine ratios, but serum lysine was significantly different among treatment groups.


Assuntos
Arginina/administração & dosagem , Bass/fisiologia , Dieta , Lisina/administração & dosagem , Aminoácidos/administração & dosagem , Criação de Animais Domésticos , Animais , Arginina/sangue , Arginina/farmacologia , Bass/crescimento & desenvolvimento , Interações Medicamentosas , Pesqueiros , Lisina/sangue , Lisina/farmacologia , Necessidades Nutricionais , Aumento de Peso/efeitos dos fármacos
13.
Dermatol Surg ; 21(12): 1017-9, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7496667

RESUMO

BACKGROUND: Carbon dioxide laser skin resurfacing using either ultrapulsed lasers or scanning skin lasers has evolved as an effective method of treating photodamaged skin. OBJECTIVE: The purpose of this paper is to describe appropriate pre- and posttreatment regimens to ensure the optimum response to laser therapy. METHODS: We describe our experiences with 30 patients treated with laser skin resurfacing using different pre- and posttreatment regimens. Patients were evaluated by physicians as regards to their responses to and recovery from laser therapy. Some patients agreed to skin biopsy and cutaneous patch testing of topically applied agents. RESULTS: Eighty percent of patients achieved good to excellent improvement. Sixty-five percent of patients undergoing laser skin resurfacing developed contact dermatitis to several topical agents. Patch testing was negative on normal skin for contact allergy, suggesting a primary irritant reaction in laser-treated skin. Post-laser hyperpigmentation and erythema were the most noted immediate and mid-term side effects to laser resurfacing. An optimum pretreatment regime includes topical retinoids, skin lightening agents, and, immediately pretreatment, oral anti-herpes simplex medication plus oral antibiotics. An optimum posttreatment regimen includes minimizing topical therapy with the use of dilute acetic acid facial soaks. In addition, oral anti-herpes simplex medications and broad spectrum antibiotics are continued for 7 days post-laser resurfacing. CONCLUSION: Laser skin resurfacing is an evolving means of treating photodamaged skin. Carefully selected pre- and posttreatment regimens, ideally under dermatologic supervision, are required to obtain optimum results.


Assuntos
Procedimentos Cirúrgicos Dermatológicos , Terapia a Laser/métodos , Cuidados Pós-Operatórios/métodos , Cuidados Pré-Operatórios/métodos , Feminino , Seguimentos , Humanos , Masculino , Complicações Pós-Operatórias/epidemiologia , Guias de Prática Clínica como Assunto , Pele/efeitos da radiação , Fatores de Tempo
14.
J Nutr ; 124(9): 1685-9, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8089736

RESUMO

Two experiments were conducted to estimate the dietary choline requirement and to determine the effects of dietary choline on liver lipid deposition in juvenile hybrid striped bass (Monrone saxatilis x M. chrysops). Experimental diets contained 0.73 g total sulfur amino acids/100 g diet (0.47 g methionine + 0.26 g cyst(e)ine/100 g diet), thus meeting, but not exceeding, the requirement. Graded levels of choline bitartrate in Experiment 1 and choline chloride in Experiment 2 were added to the basal diet, resulting in eight dietary treatments in each experiment. Dietary treatments were 0, 250, 500, 1000, 2000, 4000, 6000 and 8000 mg choline/kg dry diet. Diets were fed for 12 and 10 wk in Experiments 1 and 2, respectively. Dietary choline concentrations significantly affected weight gain, feed efficiency, survival and total liver lipid concentrations in each experiment. Weight gain and feed efficiency were greatest in fish fed 500 mg choline/kg dry diet as choline bitartrate. Total liver lipid concentrations were variable but tended to be lowest in fish fed diets containing at least 2000 mg choline/kg diet. Survival was significantly lower in the group of fish fed 8000 mg choline/kg diet supplied by choline bitartrate. Weight gain and feed efficiency were greatest and total liver lipid concentration was lowest in groups of fish fed at least 500 mg choline/kg diet as choline chloride; survival was unaffected by dietary treatment. Therefore, choline chloride seems to be a better source of dietary choline than choline bitartrate and 500 mg choline/kg diet is adequate for maximum weight gain and prevention of increased liver lipid concentration in juvenile hybrid striped bass.


Assuntos
Bass/metabolismo , Colina/administração & dosagem , Dieta , Ração Animal , Animais , Bass/crescimento & desenvolvimento , Ingestão de Alimentos , Rim/anatomia & histologia , Metabolismo dos Lipídeos , Fígado/anatomia & histologia , Fígado/metabolismo , Necessidades Nutricionais , Distribuição Aleatória , Aumento de Peso
15.
Dermatol Surg ; 21(12): 1025-9, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7496669

RESUMO

BACKGROUND: The Ultrapulse carbon dioxide (CO2) laser has been shown to be a highly effective treatment for photodamaged skin including improvement of rhytides, precancerous and benign skin lesions, as well as superficial benign pigmented lesions. OBJECTIVE: We describe our experiences using the Ultapulse CO2 laser in treating 100 patients with different severities of photodamaged skin. METHODS: All patients had moderately or severely photodamaged skin and were selected for treatment with the Ultrapulse CO2 laser to evaluate the efficacy and toxicity of this treatment. The patients were placed on a pretreatment regimen for 2-6 weeks prior to receiving treatment with the Ultrapulse CO2 laser. Patients were evaluated for pre- and posttreatment severity of photodamage. In addition, skin surface replicas were obtained in selected patients and evaluated by computer image analysis technology. RESULTS: At 1 month post-laser treatment, 68 patients received a moderate improvement, five patients achieved a marked improvement, and the remaining 27 patients showed minimal improvement. By 2 months post-laser treatment, 20 of the 27 patients who at 1 month showed only minimal improvement revealed a moderate to marked improvement from baseline. All the patients studied developed a transient erythema that lasted up to 6 weeks, and many of these patients showed a transient hyperpigmentation that persisted for up to 4 months. CONCLUSION: The Ultrapulse CO2 laser is confirmed as an effective treatment for skin resurfacing of photodamaged skin.


Assuntos
Procedimentos Cirúrgicos Dermatológicos , Terapia a Laser/instrumentação , Adulto , Estudos de Avaliação como Assunto , Feminino , Seguimentos , Humanos , Terapia a Laser/métodos , Masculino , Pessoa de Meia-Idade , Lesões Pré-Cancerosas/cirurgia , Ritidoplastia/instrumentação , Ritidoplastia/métodos , Pele/efeitos da radiação , Neoplasias Cutâneas/cirurgia , Terapia Assistida por Computador/instrumentação , Terapia Assistida por Computador/métodos , Fatores de Tempo
16.
Dermatol Surg ; 21(12): 1035-7, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7496671

RESUMO

BACKGROUND: Laser skin resurfacing is a very promising new treatment for solar elastosis and acne scars. The Ultrapulse carbon dioxide (CO2) laser and the SilkTouch flashscanner allow precise depth control and char-free ablation. Earlier studies have been done mainly on Caucasian skin types I and II, but very little data were available on pigmented skin. OBJECTIVE: The purpose of this study is to assess the efficacy and safety of laser skin resurfacing in skin types III and IV. METHODS: Thirty Asian and Hispanic patients were treated for facial rhytides and acne scars. All patients were instructed to use tretinoin cream 0.05%, hydroquinone 5%, and desonide 0.1% cream nightly for 2-4 weeks prior to the laser treatment. The Ultrapulse 5000C CO2 laser with the Truespot 3-mm collimated handpiece at the setting of 250-450 mJ per pulse, or the Silk-Touch flashscanner at the setting of 5-7 W, 0.2-second pulse duration, and 4-mm (M) spot size, was used. Patients were evaluated clinically, and global response was assessed by both clinicians and patients. RESULTS: The facial rhytides and acne scars improved 25-50% in all patients after one laser treatment. The most common side effects were persistent erythema that resolved on the average of 6 weeks. Hyperpigmentation occurred, but was reduced with regular use of tretinoin, hydroquinone, and desonide cream both pre- and postoperatively along with use of broad spectrum sunscreen after treatments. CONCLUSION: Laser skin resurfacing can be used to treat facial rhytides and acne scars in skin phototypes III and IV. When proper pre- and postoperative management is implemented, the risk of dyspigmentation can be reduced.


Assuntos
Terapia a Laser/métodos , Ritidoplastia/métodos , Pigmentação da Pele/efeitos da radiação , Acne Vulgar/cirurgia , Asiático , Estudos de Avaliação como Assunto , Feminino , Hispânico ou Latino , Humanos , Terapia a Laser/instrumentação , Masculino , Ritidoplastia/instrumentação , Terapia Assistida por Computador/instrumentação , Terapia Assistida por Computador/métodos
17.
Antonie Van Leeuwenhoek ; 68(4): 297-308, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8821785

RESUMO

The microbial community structure of twenty-one single-phase and one two-phase full-scale anaerobic sewage sludge digesters was evaluated using oligonucleotide probes complementary to conserved tracts of the 16S rRNAs of phylogenetically defined groups of methanogens and sulfate-reducing bacteria. These probe results were interpreted in combination with results from traditional chemical analyses and metabolic activity assays. It was determined that methanogens in "healthy" mesophilic, single-phase sewage sludge digesters accounted for approximately 8-12% of the total community and that Methanosarcinales and Methanomicrobiales constituted the majority of the total methanogen population. Methanobacteriales and Methanococcales played a relatively minor role in the digesters. Phylogenetic groups of mesophilic, Gram-negative sulfate-reducing bacteria were consistently present at significant levels: Desulfovibrio and Desulfobulbus spp. were the dominant sulfate-reducing populations, Desulfobacter and Desulfobacterium spp. were present at lower levels, and Desulfosarcina, Desulfococcus, and Desulfobotulus spp. were absent. Sulfate reduction by one or more of these populations played a significant role in all digesters evaluated in this study. In addition, sulfate-reducing bacteria played a role in favoring methanogenesis by providing their substrates. The analysis of the two-phase digester indicated that true phase separation was not accomplished: significant levels of active methanogens were present in the first phase. It was determined that the dominant populations in the second phase were different from those in the single-phase digesters.


Assuntos
Bactérias Anaeróbias/isolamento & purificação , Sondas de DNA , Euryarchaeota/isolamento & purificação , RNA Ribossômico 16S/análise , Esgotos/microbiologia , Sulfatos/metabolismo , Bactérias Anaeróbias/genética , Bactérias Anaeróbias/metabolismo , Reatores Biológicos , Euryarchaeota/genética , Euryarchaeota/metabolismo , Metano/metabolismo , Oxirredução , Filogenia , RNA Ribossômico 16S/genética , Eliminação de Resíduos Líquidos
18.
Biotechnol Bioeng ; 57(3): 342-55, 1998 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-10099211

RESUMO

An aggressive start-up strategy was used to initiate codigestion in two anaerobic, continuously mixed bench-top reactors at mesophilic (37 degrees C) and thermophilic (55 degrees C) conditions. The digesters were inoculated with mesophilic anaerobic sewage sludge and cattle manure and were fed a mixture of simulated municipal solid waste and biosolids in proportions that reflect U.S. production rates. The design organic loading rate was 3.1 kg volatile solids/m3/day and the retention time was 20 days. Ribosomal RNA-targeted oligonucleotide probes were used to determine the methanogenic community structure in the inocula and the digesters. Chemical analyses were performed to evaluate digester performance. The aggressive start-up strategy was successful for the thermophilic reactor, despite the use of a mesophilic inoculum. After a short start-up period (20 days), stable performance was observed with high gas production rates (1.52 m3/m3/day), high levels of methane in the biogas (59%), and substantial volatile solids (54%) and cellulose (58%) removals. In contrast, the mesophilic digester did not respond favorably to the start-up method. The concentrations of volatile fatty acids increased dramatically and pH control was difficult. After several weeks of operation, the mesophilic digester became more stable, but propionate levels remained very high. Methanogenic population dynamics correlated well with performance measures. Large fluctuations were observed in methanogenic population levels during the start-up period as volatile fatty acids accumulated and were subsequently consumed. Methanosaeta species were the most abundant methanogens in the inoculum, but their levels decreased rapidly as acetate built up. The increase in acetate levels was paralleled by an increase in Methanosarcina species abundance (up to 11.6 and 4.8% of total ribosomal RNA consisted of Methanosarcina species ribosomal RNA in mesophilic and thermophilic digesters, respectively). Methanobacteriaceae were the most abundant hydrogenotrophic methanogens in both digesters, but their levels were higher in the thermophilic digester.


Assuntos
Euryarchaeota/metabolismo , Eliminação de Resíduos/métodos , Anaerobiose , Animais , Biodegradação Ambiental , Reatores Biológicos , Biotecnologia , Bovinos , Euryarchaeota/genética , Ácidos Graxos Voláteis/metabolismo , Fermentação , Concentração de Íons de Hidrogênio , RNA Arqueal/genética , RNA Ribossômico/genética , Esgotos , Temperatura
19.
Biochem Biophys Res Commun ; 252(2): 487-91, 1998 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-9826557

RESUMO

PCR amplifications with two sets of degenerate primers that were targeted to CYP26-specific regions were performed with cDNAs from human fetal liver and brain as templates. PCR products were purified, cloned, sequenced and analyzed with the BLAST program. Our results revealed expression of CYP26 in both human fetal liver and brain. Furthermore, human fetal CYP26 cDNA exhibited 99.2%-100% nucleotide sequence identity to its adult counterpart. Novel isoforms, that would have indicated additional CYP26 genes, were not found. A Northern blot containing poly(A+)RNAs from 43 human adult and 7 human fetal tissues was tested for CYP26 expression. We were able to detect CYP26 message in most tissues but hybridization signals varied in intensity. Highest levels of transcription were in adult liver, heart, pituitary gland, adrenal gland, placenta and regions of the brain. CYP26 expression in fetal tissues was strongest in the brain and comparable with message levels in adult tissues.


Assuntos
Encéfalo/enzimologia , Sistema Enzimático do Citocromo P-450/genética , Fígado/enzimologia , Oxigenases de Função Mista/genética , Adulto , Sequência de Aminoácidos , Sequência de Bases , Primers do DNA/genética , DNA Complementar/genética , Feminino , Feto/enzimologia , Expressão Gênica , Humanos , Reação em Cadeia da Polimerase , Gravidez , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ácido Retinoico 4 Hidroxilase , Distribuição Tecidual
20.
Diabet Med ; 14(9): 741-7, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9300223

RESUMO

Autoantibodies to oxidized low density lipoprotein have been shown to be an independent predictor of the progression of carotid atherosclerosis. This study examines the relationship between low density lipoprotein fatty acid composition and autoantibodies to both malondialdehyde-modified and copper-oxidized low density lipoprotein in non-diabetic patients with (n = 17), and without (n = 18), definite evidence of previous myocardial infarction. The third group were non-insulin-dependent diabetic patients with no evidence of atherosclerosis (n = 15) and the fourth group were patients with non-insulin-dependent diabetes (n = 17) who had definite evidence of previous myocardial infarction. Fatty acids were measured by gas-liquid chromatography. Antibodies to malondialdehyde-modified low density lipoprotein and copper-oxidized low density lipoprotein were determined by an ELISA method. Autoantibodies to copper-oxidized low density lipoprotein were significantly higher in the non-diabetic patients with heart disease when compared to any other group (p < 0.05). Autoantibodies to malondialdehyde-modified low density lipoprotein were significantly higher in the non-diabetic subjects with heart disease and in both diabetic groups compared to non-diabetic subjects without coronary heart disease (p < 0.05). Linoleic acid (%) in low density lipoprotein did not differ between groups groups but arachidonic acid (%) was significantly lower in both diabetic and non-diabetic patients with coronary heart disease (p < 0.05). The diabetic patients with low antibodies had 39.6 +/- 2.2% polyunsaturated fatty acids in their low density lipoprotein while diabetic patients with high antibodies had 46.7 +/- 1.2% polyunsaturates in their low density lipoprotein (p < 0.01). This study confirms the association between antibodies to oxidized low density lipoprotein and coronary heart disease and shows raised low density lipoprotein antibody levels in diabetic patients with and without demonstrable atherosclerosis. In the diabetic patients, those with high antibody levels had high polyunsaturated fatty acid levels in their LDL suggesting a possible role for dietary intervention.


Assuntos
Autoanticorpos/sangue , Diabetes Mellitus Tipo 2/imunologia , Ácidos Graxos/análise , Lipoproteínas LDL/química , Lipoproteínas LDL/imunologia , Idoso , Arteriosclerose/etiologia , Arteriosclerose/imunologia , Autoanticorpos/imunologia , Estudos de Coortes , Cobre/metabolismo , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Lipoproteínas LDL/metabolismo , Masculino , Malondialdeído/metabolismo , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Infarto do Miocárdio/imunologia , Oxirredução
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