RESUMO

Abstract A selective, sensitive and precise reversed phase HPLC-DAD method was developed and validated for the simultaneous determination of six phenolic acids in the aqueous extract and their hydrolyzed forms prepared from Solanum elaeagnifolium Cav., Solanaceae, Ampelocissus acapulcensis (Kunth) Planch., Vitaceae, or Brosimum alicastrum Sw., Moraceae. The new method showed good linearity (r > 0.999) in a relatively wide concentration range (0.5-100 mg/l). The limits of detection and quantification for the compounds were in the range of 0.097-0.467 mg/l and 0.097-0.496 mg/l, respectively. The recoveries of compounds were calculated in three different concentrations in the range of 88.07-109.17% and matrix effect was less than 5% for all phenolic acids. Finally, our developed HPLC method is simple, reliable and successfully applied to identify and quantify the phenolic acids in complex aqueous extracts from medicinal species, that can be useful for the analysis of infusions that people consume in folk medicine.

RESUMO

Lead is a commonly monitored heavy metal because of potential health effects on exposed organisms. We quantified lead in secondary feathers of two passerine bird species, clay-colored thrushes (Turdus grayi) and great-tailed grackles (Quiscalus mexicanus), from an urban and a rural site in the municipality of Merida, Yucatan. Urban lead concentration was significantly higher than its rural counterpart for both species (p < 0.05). In the urban site, lead concentration was similar in both species (p = 0.14). However, data from the rural site showed that lead concentration was significantly higher in thrush feathers (p < 0.05). Lead levels herein presented are among the lowest ever reported suggesting that either lead accumulation or absorption is limited. Finally, our data seem to support the hypothesis that species feeding ecology plays a major role in lead accumulation.

Assuntos

RESUMO

Joven masculino, de la raza negra, de 41 años de edad, que en el año 1999, acude a consulta de urología del Hospital General "Abel Santamaría Cuadrado" por un aumento de volumen del testículo izquierdo, no doloroso con diagnóstico clínico e imaginológico de tumor testicular izquierdo, es ingresado en el servicio de Urología, realizándole el tratamiento quirúrgico (orquiectomia izquierda ) constatándose el resultado biópsico que reporta seminoma clásico, clasificado (T1N1M0), asociando radioterapia y quimioterapia una evolución satisfactoria. El paciente es seguido en las consultas periódicas multidisciplinarías oncourológicas, en el 2009, 10 años después refiere dolor en testículo derecho, aumento de volumen en la porción media e inferior, que se interpreta de inicio como una orquiepididimitis, recibiendo un tratamiento con antibióticos (ciprofloxacina, amoxicilina ) sin respuesta al tratamiento. Los exámenes imageneológicos USG; TAC reportan imágenes nodulares con densidades variables en relación con proceso inflamatorio o tumoral y escasas adenopatías retroperitoniales e inguinales bilaterales la mayor 13mm, por lo que se decide realizar BAFF testicular derecho, comprobándose la existencia de células malignas. Se realiza la orquiectomia derecha, con el diagnóstico histopatológico seminoma testicular clásico T1NOMO-S0 (Etapa Clínica 1A). La evolución post operatoria es satisfactoria, se indica suplemento androgénico y radioterapia 30Gy. Actualmente asintomático.

A 41 years-old, black, male patient who in 1999 attended to the urology office at "Abel Santamaria Cuadrado" University Hospital with an increase of volume in the left testis, non-painful having the clinical and imaging diagnose of left testicular tumor, the patient was admitted in the Urology Service to undergo surgical treatment (left orchiectomy), verifying by biopsy, a classic seminoma, which was classified as T1N1MO. Radiotherapy and chemotherapy was indicated showing a satisfactory progress. The patient was followed-up in periodic multidisciplinary, onco-urologic consultations. In 2009, 10 years after, the patient complained of pain in the right testis, increase of volume in the middle-inferior portion of the testis that was interpreted as a process of epididymo-orchitis, starting with antibiotics (ciprofloxacin, amoxicillin),where no-treatment response was observed. Imaging examinations showed nodular imagines with variable densities in relation to an inflammatory or tumoral process and limited retro-perineal and inguinal-bilateral adenopathies <13mm, performing a BAAF in the right testis which verified the existence of malignant cells, a right orchiectomy was carried out, pathologic findings showed a classic testicular seminoma T1NOMO-S0 (Clinical stage 1A). Post operative progress is satisfactory, indicating the treatment of androgenic supplements and y-radiotherapy (30Gy). Currently the patient is asymptomatic.

RESUMO

AIM: To investigate whether oral treatment with D-004, a lipid extract of the Cuban royal palm fruit, produces antioxidant effects in the prostate tissue of normal and testosterone (T)-treated rats. METHODS: In our first experiment, normal rats were distributed into five groups: one group treated with the vehicle and four groups treated with D-004 (100, 200, 400 or 800 mg/kg). In our second experiment, rats were randomized into five groups: a negative control group and four T-injected groups. The latter were comprised of a positive control group treated with the vehicle, and three groups treated with D-004 (200, 400 or 800 mg/kg). RESULTS: In normal rats, D-004 (100-800 mg/kg) inhibited significantly and dose-dependently iron-initiated malondialdehyde (MDA) accumulation in prostate homogenates (35.7%-80.0%) vs the controls. D-004 (200-800 mg/kg) significantly reduced baseline MDA and carbonyl groups in prostate homogenates of normal rats to approximately 80% and 50%, respectively, and totally (100%) in T-treated rats. CONCLUSION: Oral treatment with D-004 reduced MDA and carbonyl groups dose-dependently and markedly in normal and T-injected rats. These findings show that D-004 given at doses effective to prevent prostate hyperplasia also produces antioxidant effects in the prostate tissue.

Assuntos

RESUMO

BACKGROUND: D-004, a lipid extract of the fruit of the Cuban royal palm (Roystonea regia), has been found to reduce prostatic hyperplasia (PH) induced with testosterone (T), but not PH induced with dihydrotestosterone (DHT), in rodents, suggesting the inhibition of prostate 5α-reductase activity. OBJECTIVES: The aims of this study were to assess whether D-004 inhibits prostate 5α-reductase activity in vitro and to examine the effects of D-004 on enzyme kinetics. METHODS: This experimental study was conducted at the Pharmacology Department, Center of Natural Products, National Center for Scientific Research, Havana, Cuba. Soluble rat prostate preparations were used as the source of 5α-reductase, and ((3)H)-DHT production was measured to determine prostate 5α-reductase activity. Cell-free rat prostate homogenates were pre-incubated with carboxymethyl cellulose 2% alone (control tubes) or D-004 (0.24-125 µg/mL) suspended in the vehicle (treated tubes) for 10 minutes prior to adding the labeled substrate ((3)H)-T Once the reaction was stopped, sterols were extracted with chloroform and aliquots were applied on silica gel plates developed in benzene-acetone (4:1, v/v). Areas containing DHT were scraped and radioactivity was counted. The median inhibitory concentration (IC50) was determined by measuring the conversion of T to DHT The apparent Michaelis-Menten constant (Km) and Vmax values before and after adding D-004 were determined in kinetic studies using labeled T (0.5-25 µmol/L). RESULTS: Compared with controls, D-004 significantly and dose-dependently inhibited the enzymatic reaction at doses of 1.95 to 125.0 µg/mL) (all, P < 0.05). The IC50 of D-004 required to inhibit 5a-reductase activity was 2.25 µg/mL. Enzyme inhibition was noncompetitive, since D-004 lowered the Vmax from 15.3 to 10.0 nmol DHT/min · mg(-1) protein, while the Km (4.54 µmol/L) was almost unaffected. CONCLUSIONS: D-004 dose-dependently and noncompetitively inhibited in vitro 5α-reductase activity in soluble fractions of rat prostate. Although the extent of the maximal inhibition was high and the value of IC50 was low, the relevance of such inhibition requires further study in vivo.

RESUMO

BACKGROUND: D-004, a lipid extract of the fruit of Roystonea regia, contains a mixture of fatty acids-mainly oleic, lauric, palmitic, and myristic acids, with oleic acid being among the most abundant-that has been found to reduce the risk for prostatic hyperplasia (PH) induced with testosterone (T) in rats. The pharmacokinetic profile of D-004 has not been reported. OBJECTIVE: The objective of this study in rats was to assess plasma levels, tissue distribution, and excretion of total radioactivity (TR) after single-dose administration of oral D-004 radiolabeled with ((3)H)-oleic acid, as a surrogate for the pharmacokinetics of D-004. METHODS: This experimental study was conducted at the Pharmacology Department, Center of Natural Products, National Center for Scientific Research, Havana, Cuba. Single doses of suspensions of ((3)H)-oleic acid 0.16 µCi/mg mixed with D-004 400 mg/kg (radioactive dose/animal 7.2 µCi) were given orally to male Wistar rats weighing 150 to 200 g assigned to the treated or control group. Three rats were euthanized at each of the following times: 0.25, 0.5, 1, 1.5, 2, 4, 8, 24, 48, 72, 96, and 144 hours after study drug administration. After administration, the rats euthanized at the last experimental time point were housed individually in metabolism cages. Urine and feces samples were collected daily. At each time point, blood samples were drawn and plasma samples were obtained using centrifugation. After euthanization, tissue samples (liver, lungs, spleen, brain, kidneys, adipose tissue, muscle, stomach, small and large intestines, adrenal glands, heart, testes, prostate, and seminal vesicles) were quickly removed, washed, blotted, and homogenized. Plasma (100 µL), tissue aliquots (100 mg), feces (10 mg), and urine (100µL) were dissolved and TR was measured. Samples were assayed in duplicate. Results were expressed in µgEq of radio-labeled oleic acid per milliliter of plasma or urine or gram of tissue or feces. Plasma, tissue, feces, and urine samples of rats that did not receive ((3)H)-oleic acid were used as controls. Excretion was expressed as the percentage of the radioactivity excreted via each route with respect to the total radioactive dose administered to each rat. RESULTS: A total of 50 rats were included in the experiment (mean age, 4 weeks; mean weight, 310 g). Absorption was rapid; mean Cmax was 195.56 (31.12) µgEq/mL, and mean Tmax was 2 hours. Thereafter, a biphasic decay of TR was found: a rapid first phase (t1/2α, 1.33 hours), followed by a slower second elimination phase (t1/2ß, 36.07 hours). Radioactivity was rapidly and broadly distributed throughout the tissues, with more accumulating in the prostate than elsewhere. In the first 8 hours, accumulation of TR was greatest in the prostate, followed by the liver, small intestine, and plasma. Subsequently, TR increased in the small intestine, while it decreased in the liver and plasma. In contrast, over the periods of 24 and 144 hours after administration, TR increased in the adipose tissue, while it decreased in the other tissues and plasma. During those intervals, TR was greatest in the prostate, followed by adipose tissue. Mean peak radioactivity in the prostate (562.41 µgEq/g) was reached at 4 hours and decreased slowly thereafter. The prostate had the highest values of t1/2ß and cumulative AUC compared with the other tissues and plasma. Mean (SD) TR was similar in feces (33.48% [4.90%]) and urine (28.96% [5.32%]), with total excretion being 62.40% (5.90%) of the administered dose. CONCLUSIONS: In this experimental study, after single-dose administration of oral D-004 radiolabeled with ((3)H)-oleic acid in rats, TR was rapidly and widely distributed across the tissues, with the prostate having the highest accumulation of radioactivity. Excretion of TR was limited, with similar amounts being excreted in feces and urine. The broad distribution of radiolabeled oleic acid and/or its metabolites suggests (SD) pharmacokinetic rationale for the effectiveness of D-004 in reducing the risk for PH induced with T in rats.

RESUMO

BACKGROUND: D-003 is a mixture of long-chain aliphatic primary acids purified from sugarcane wax with hypocholesterolaemic effects proven in rabbits and healthy volunteers; it lowers serum total cholesterol (TC) and low-density lipoprotein-cholesterol (LDL-C) and increases high-density lipoprotein-cholesterol (HDL-C). D-003 also prevents lipoprotein lipid peroxidation in experimental models. OBJECTIVE: To investigate the effects of D-003 on lipid profile and lipid peroxidation in healthy human volunteers. PARTICIPANTS: Forty-six healthy volunteers (24 women, 22 men). METHODS: This double-blind, randomised, placebo-controlled study investigated the effects of D-003 at 5 and 10 mg/day on the susceptibility of LDL to lipid peroxidation induced by copper ions in healthy volunteers. Forty-six individuals were randomised (1 : 2) to placebo or D-003 at 5 or 10 mg/day, the tablets being taken once a day with the evening meal for 8 weeks. Laboratory determinations and physical examination were performed at baseline and after 4 and 8 weeks of therapy, and compliance and adverse experience assessments were performed at weeks 4 and 8. RESULTS: All groups were well matched at baseline. At study completion, D-003 at 5 and 10 mg/day significantly (p < 0.001) lowered LDL-C, the primary response variable, by 20.8% and 28.8%, respectively. In addition, D-003 at 5 and 10 mg/day reduced (p < 0.001) TC (12.7% and 17.5%, respectively), LDL-C/ HDL-C (25.9% and 36.3%, respectively) and TC/HDL-C (18.6% and 26.3%, respectively), while significantly (p < 0.01) increasing HDL-C (7.7% and 12.4%, respectively). Triglycerides were significantly (p < 0.05) reduced (8.8% and 13.1%, respectively) with respect to baseline, but not versus placebo. Responses assessed at 4 weeks showed significant reductions of LDL-C, TC and atherogenic ratios with both doses of D-003, whereas HDL-C was significantly increased. Triglycerides, however, remained unchanged. No significant changes in any lipid profile variable occurred in the placebo group. D-003 at 5 and 10 mg/day significantly (p < 0.05) increased lag time (18.3% and 32.0%, respectively) and decreased maximum rate of diene propagation (V(max)) [12.7% and 19.1%, respectively] of copper-induced LDL peroxidation. D-003 5 and 10 mg/day attenuated the reduction of the reactivity against 2, 4, 6-trinitrobenzene sulfonic acid (TNBS) by 19.9% and 32.0%, respectively. The treatment was well tolerated. Three subjects (one from each group) discontinued the study. Only one, treated with D-003 5 mg/day, discontinued because of an adverse event (gastritis). CONCLUSIONS: D-003 at 5 and 10 mg/day demonstrated dose-dependent cholesterol-lowering effects in healthy volunteers characterised by reductions in LDL-C, TC and atherogenic ratios, and increases in HDL-C. Effects on triglycerides were modest and uncertain. As expected from experimental studies, D-003 inhibited the susceptibility of LDL to lipid peroxidation assessed by three indicators lag time V(max) and reactivity versus TNBS. Further studies investigating the effect of larger doses and treatment duration must be conducted to confirm the reproducibility of the present results in different study populations.

RESUMO

Biografia escrita em homenagem ao centenário da morte de Antonio Mestre, expositor do darwinismo em Cuba no século XIX; fundador da revista científica Anales da antiga Academia; crítico do obscurantismo anti-científico e pseudo-científico; o primeiro a organizar um curso moderno de história da medicina na Universidade de Havana; e iniciador de uma tradiçäo pediátrica e médico-legal.(MAM)

Assuntos

RESUMO

Biografia escrita em homenagem ao centenário da morte de Antonio Mestre, expositor do darwinismo em Cuba no século XIX; fundador da revista científica Anales da antiga Academia; crítico do obscurantismo anti-científico e pseudo-científico; o primeiro a organizar um curso moderno de história da medicina na Universidade de Havana; e iniciador de uma tradiçäo pediátrica e médico-legal.(MAM)

Assuntos