Shorter telomere length and suicidal ideation in familial bipolar disorder.

Bipolar Disorder (BD) has recently been related to a process of accelerated aging, with shortened leukocyte telomere length (LTL) in this population. It has also been observed that the suicide rate in BD patients is higher than in the general population, and more recently the telomere length variation has been described as shorter in suicide completers compared with control subjects. Objectives The aim of the present study was to investigate if there is an association between LTL and BD in families where two or more members have BD including clinical symptomatology variables, along with suicide behavior. Methods Telomere length and single copy gene ratio (T/S ratio) was measured using quantitative polymerase chain reaction in a sample of 143 relatives from 22 families, of which 60 had BD. The statistical analysis was performed with a polygenic mixed model. Results LTL was associated with suicidal ideation (p = 0.02) as that there is an interaction between suicidal ideation and course of the disorder (p = 0.02). The estimated heritability for LTL in these families was 0.68. In addition, covariates that relate to severity of disease, i.e. suicidal ideation and course of the disorder, showed an association with shorter LTL in BD patients. No difference in LTL between BD patients and healthy relatives was observed. Conclusion LTL are shorter in subjects with familial BD suggesting that stress related sub-phenotypes possibly accelerate the process of cellular aging and correlate with disease severity and suicidal ideation.

Comparison between criteria for diagnosing malnutrition in patients with advanced chronic liver disease: GLIM group proposal versus different nutritional screening tools.

BACKGROUND: Different nutritional screening instruments can be used to identify the risk of malnutrition in advanced chronic liver disease patients. The present study aimed to evaluate and compare two nutrition screening tools with the Global Leadership Initiative on Malnutrition (GLIM) diagnostic criteria for malnutrition in patients with advanced chronic liver disease. METHODS: Two nutritional screening tools, Nutritional Risk Screening 2002 (NRS-2002) and Royal Free Hospital Nutritional Prioritizing Tool (RFH-NPT), were assessed for 166 patients with liver cirrhosis. We compared medium/high nutritional risk screening with the diagnosis of malnutrition, using the GLIM criteria as the reference standard. RESULTS: According to the GLIM criteria, 57.3% of the patients were malnourished. NRS and RFH-NPT identified, respectively, 36.1% and 52.4% of patients with nutritional risk. RFH-NPT presented better agreement with the diagnosis according to GLIM criteria (k = 0.64; 95% confidence interval = 0.52-0.75), higher sensitivity (80%), higher negative predictive value (79%) and larger area under the curve (82.3%) compared to the NRS. CONCLUSIONS: RFH-NPT, when compared with the GLIM method, has substantial agreement in identifying nutritional risk, good sensitivity and good value for diagnosing malnutrition in patients with advanced chronic liver disease.

Prevalence and screening of active tuberculosis in a prison in the South of Brazil.

SETTING: Tuberculosis (TB) remains a challenge in Brazil, particularly among prison inmates. OBJECTIVE: To assess TB prevalence by active case finding in a public prison in southern Brazil. DESIGN: Prison inmates were screened for TB using the presence of cough and chest X-ray (CXR) from October 2014 to August 2016. Presence of cough, irrespective of duration, and abnormal CXRs were further investigated using laboratory tests. RESULTS: Of 10 326 inmates screened, 196 had confirmed TB (1898/100 000 inmates screened). At the first screening, 1759 inmates presented with cough only, 16 of whom had TB; among those with only abnormal CXR (n = 1273), 92 had TB. Xpert was positive in 155 patients, and negative in 15; these results were confirmed using culture. The remaining 26 patients did not undergo Xpert testing and were confirmed using microscopy (27%), culture (42%) or both (31%). CONCLUSION: The combined use of symptom screening (cough) and CXR was much more effective in maximising TB yield than using either method alone. If patients presenting with cough alone had not been investigated, 10% of TB patients would have been missed; if those with abnormal CXR but no cough had not been investigated, 51% of TB patients would have been missed. We detected high TB prevalence in this prison by using active case finding.

Bioaccumulation of nickel in tomato plants: risks to human health and agro-environmental impacts.

Anthropogenic activities such as agriculture, industry, and mining have contributed significantly to the accumulation of heavy metals in the soil, which in turn cause problems to human health and to the environment. The present work aims to study the effects of nickel (Ni) on the development of tomato plants, the risks to human health associated to the consumption of contaminated tomatoes, and the consequences to the environment. The experiment was carried out in greenhouse environment for a period of 120 days, and the plants were cultivated in soils with four different concentrations of Ni: 0, 35, 70, and 105 mg kg-1. The concentration of nickel in each part (root, stem, leaf, and fruit) of the tomato plant was measured at four different stages of the cycle: 30, 60, 90, and 120 days, by inductively coupled plasma optical emission spectrometer (ICP-OES). At the end of the cycle, the concentration of certain macro- and micronutrients was also determined and related to the corresponding Ni concentration in the soil. The distribution of Ni in the parts of the plant was analyzed from the bioaccumulation factor temporal behavior. Nickel concentrations found in the fruit were too low to pose a risk to human health. As a result of this research, it was verified that soils with nickel concentrations close to 70 mg kg-1, which is the limit established by the CONAMA resolution (420/2009), may actually represent an optimum concentration value for the development of tomato plants. It also increases productivity per plant and reduces the use of resources such as water and agricultural inputs.

n-3 polyunsaturated fatty acid supplementation reduces insulin resistance in hepatitis C virus infected patients: a randomised controlled trial.

BACKGROUND: Insulin resistance promotes liver disease progression and may be associated with a lower response rate in treated hepatitis C virus (HCV) infected patients. n-3 polyunsaturated fatty acid (PUFA) supplementation may reduce insulin resistance. The present study aimed to evaluate the effect of n-3 PUFA supplementation on insulin resistance in these patients. METHODS: In a randomised, double-blind clinical trial, 154 patients were screened. After applying inclusion criteria, 52 patients [homeostasis model assessment index of insulin resistance (HOMA-IR ≥2.5)] were randomly divided into two groups: n-3 PUFA (n = 25/6000 mg day(-1) of fish oil) or control (n = 27/6000 mg day(-1) of soybean oil). Both groups were supplemented for 12 weeks and underwent monthly nutritional consultation. Biochemical tests were performed at baseline and after intervention. Statistical analysis was performed using the Wilcoxon Mann-Whitney test for comparisons and the Wilcoxon test for paired data. Statistical package r, version 3.02 (The R Project for Statistical Computing) was used and P < 0.05 (two-tailed) was considered statistically significant. RESULTS: Comparisons between groups showed that n-3 PUFA supplementation was more effective than the control for reducing HOMA-IR (P = 0.015) and serum insulin (P = 0.016). The n-3 PUFA group not only showed a significant reduction in HOMA-IR 3.8 (3.2-5.0) versus 2.4 (1.8-3.3) (P = 0.002); serum insulin 17.1 (13.8-20.6) µIU mL(-1) versus 10.9 (8.6-14.6) µIU mL(-1) (P = 0.001); and glycated haemoglobin 5.4% (5.0-5.7%) versus 5.1% (4.8-5.6%) (P = 0.011), but also presented an increase in interleukin-1 97.5 (0.0-199.8) pg mL(-1) versus 192.4 (102.2-266.8) pg mL(-1) (P = 0.003) and tumour necrosis factor 121.2 (0.0-171.3) pg mL(-1) versus 185.7 (98.0-246.9) pg mL(-1) (P = 0.003). CONCLUSIONS: n-3 PUFA supplementation reduces insulin resistance in genotype 1 HCV infected patients.

HOXB7 mRNA is overexpressed in pancreatic ductal adenocarcinomas and its knockdown induces cell cycle arrest and apoptosis.

BACKGROUND: Human homeobox genes encode nuclear proteins that act as transcription factors involved in the control of differentiation and proliferation. Currently, the role of these genes in development and tumor progression has been extensively studied. Recently, increased expression of HOXB7 homeobox gene (HOXB7) in pancreatic ductal adenocarcinomas (PDAC) was shown to correlate with an invasive phenotype, lymph node metastasis and worse survival outcomes, but no influence on cell proliferation or viability was detected. In the present study, the effects arising from the knockdown of HOXB7 in PDAC cell lines was investigated. METHODS: Real time quantitative PCR (qRT-PCR) (Taqman) was employed to assess HOXB7 mRNA expression in 29 PDAC, 6 metastatic tissues, 24 peritumoral tissues and two PDAC cell lines. siRNA was used to knockdown HOXB7 mRNA in the cell lines and its consequences on apoptosis rate and cell proliferation were measured by flow cytometry and MTT assay respectively. RESULTS: Overexpression of HOXB7 mRNA was observed in the tumoral tissues and in the cell lines MIA PaCa-2 and Capan-1. HOXB7 knockdown elicited (1) an increase in the expression of the pro-apoptotic proteins BAX and BAD in both cell lines; (2) a decrease in the expression of the anti-apoptotic protein BCL-2 and in cyclin D1 and an increase in the number of apoptotic cells in the MIA PaCa-2 cell line; (3) accumulation of cell in sub-G1 phase in both cell lines; (4) the modulation of several biological processes, especially in MIA PaCa-2, such as proteasomal ubiquitin-dependent catabolic process and cell cycle. CONCLUSION: The present study confirms the overexpression of HOXB7 mRNA expression in PDAC and demonstrates that decreasing its protein level by siRNA could significantly increase apoptosis and modulate several biological processes. HOXB7 might be a promising target for future therapies.

Possible molecular mechanisms soy-mediated in preventing and treating nonalcoholic fatty liver disease.

The aim of this review is to describe the molecular mechanisms of nonalcoholic fatty liver disease (NAFLD) and to present evidence regarding the mechanisms of soy-mediated therapeutic activity in preventing and treating NAFLD. NAFLD is induced by multiple metabolic pathways, including an increase in the release of fatty acids from the adipose tissue (lipolysis), insulin resistance (IR), and an increase in "de novo" fatty acid synthesis. Furthermore, NAFLD is correlated with a decrease in liver ß-oxidation, an increase in oxygen free radical production, and an increase in pro-inflammatory cytokine production, which leads to an increase in liver fat and, subsequently, to tissue damage. The bioactive compounds in soy can prevent and treat NAFLD by modulating lipid metabolism and regulating the expression of related transcription factors. Soy intake decreases the expression of sterol regulatory-element binding protein-lc (SREBP-1) and increases the expression of SREBP-2, which are transcription factors associated with the regulation of hepatic lipogenesis and reduction of cholesterol synthesis and absorption in the liver, respectively. Besides, interactions between soy components, such as standard amino acids, polyunsaturated fat, and the isoflavonoid-enriched fraction, are believed to improve fatty acid oxidation in the liver parenchyma by increasing the expression of peroxisome proliferator-activated receptor α (PPARα)-regulated genes, thus decreasing lipid accumulation in the liver. Therefore, including soy-derived foods in the diet as a therapeutic tool for patients with NAFLD might improve their clinical evolution.

New approaches to clarify antinociceptive and anti-inflammatory effects of the ethanol extract from Vernonia condensata leaves.

The present study was aimed at evaluating the antinociceptive and anti-inflammatory effects of the ethanol extract from Vernonia condensata leaves in animal models, in order to afford a better understanding of these properties. The extract reduced the number of abdominal contortions at doses of 100 (51.00 ± 3.00), 200 (42.00 ± 2.98) and 400 mg/kg (39.00 ± 4.00). In formalin tests, a significant reduction in the licking time (p < 0.01) was observed in the first phase by 25.14 (200 mg/kg = 51.50 ± 4.44) and 31.15% (400 mg/kg = 48.00 ± 4.37). The doses of 100 (43.37 ± 5.15), 200 (34.62 ± 4.16) and 400 mg/kg (28.37 ± 3.98) inhibited (p < 0.001) the second phase. After 60 and 90 min of treatment, a dose of 400 mg/kg (10.13 ± 0.39 and 11.14 ± 1.33, respectively) increased the latency time. Doses of 200 and 400 mg/kg potentiated the sleeping time induced by diazepam, pentobarbital and meprobamate. The extracts (100, 200 and 400 mg/kg) showed anti-inflammatory effects by a decrease in paw edema. The extracts also reduced the exudate volume at the doses of 200 and 400 mg/kg. The leukocyte migration had significant effect (p < 0.001) at doses of 100, 200 and 400 mg/kg. The completion of additional experiments in the investigation of the antinociceptive and anti-inflammatory activities of V. condensata allowed a better understanding of the central and peripheral mechanisms involved.

Inorganic As speciation and bioavailability in estuarine sediments of Todos os Santos Bay, BA, Brazil.

The spatial distribution of As (total As, As (III) and As (V)) in estuarine sediments from the main tributaries of Todos os Santos Bay, BA, Brazil, was evaluated under high and low flow conditions. The concentrations of As were determined using a slurry sampling procedure with hydride generation atomic absorption spectrometry (HG-AAS). The highest concentrations were observed at estuary mouths, and exceeded conservative lower threshold value (Threshold Effects Level; TEL). Due to the oxic conditions and abundance of Mn and Fe (oxyhydr)oxides in the sediments, most inorganic arsenic in the Subaé and Paraguaçu estuaries was present as As (V). Nevertheless, the concentration of As (III) at several locations along the Jaguaripe River were also above the TEL value, suggesting that As may be toxic to biota. In the Subaé estuary, antropogenic activities are the main source of As. At the Jaguaripe and at Paraguaçu estuaries, nevertheless, natural sources of As need to be considered to explain the distribution patterns.

Amino acids change liver growth factors gene expression in malnourished rats.

BACKGROUND: Glutamine and proline are metabolized the liver and may collaborate on its regeneration. Parenteral nutrition (PN) containing either glutamine or proline was given to partially hepatectomized rats. The total RNA content and growth factor gene expression in hepatic remnants was measured, to determine the effects of these amino acid supplementation on the expression of growth factors during liver regeneration. METHODS: Wistar rats nourished (HN) and malnourished (HM) were hepatectomized and divided in two groups: 20 receiving PN enriched with Alanyl-Glutamine (HN-Gln and HM-Gln) and 20 PN enriched with proline+alanine (HN-Pro and HM-Pro). The control groups comprised 7 nourished (CN) and 7 malnourished (CM) rats that didn't undergo surgery. Growth factor and thymidine kinase mRNA levels were measured by RT-PCR. RESULTS: In nourished rats, total hepatic RNA levels were lower in the HN-Gln and HN-Pro groups (0.75 and 0.63 microg/mg tissue, respectively) than in control group (1.67 microg/mg tissue) (P<0.05). In malnourished rats, total hepatic RNA content was higher in the HM-Pro group than HN-Pro, HM-Gln, and CM (3.18 vs. 0.63, 0.93 and 1.10 microg/mg, respectively; P<0.05). Hepatocyte growth factor mRNA was more abundant in the HM-Gln group when compared to CM (0.31 vs. 0.23 arbitrary units) and also in HM-Pro in relation to HM-Gln, HN-Pro, and CM(0.46 vs. 0.33 and 0.23, respectively, P<0.05). CONCLUSIONS: Proline or glutamine supplementation in malnourished rats improves total RNA content in the remnant hepatic tissue. Amino acids administration increased HGF gene expression after partial hepatectomy in malnourished rats, with a greater effect of proline than glutamine.

Neurobiological pathways to Alzheimers disease: Amyloid-beta, Tau protein or both? / Trajetórias neurobiológicas para a doença de Alzheimer: beta-amilóide, proteína Tau ou ambas?

Abstract: Alzheimers disease (AD) is a neurodegenerative disease characterized by progressive cognitive decline, including memory loss, behavioral and psychological symptoms and personality changes. The neuropathological hallmarks of AD are the presence of neuritic (senile) plaques (NP) and neurofibrillary tangles (NFT), along with neuronal loss, dystrophic neurites, and gliosis. Neuritic plaques are extracellular lesions and their main constituent is the amyloid-beta42 peptide (A- beta42). Neurofibrillary tangles are intracellular lesions that are mainly composed of hyperphosphorylated ta u protein. In this article, we review the major hypotheses concerning the physiopathology of AD, focusing on the beta-amyloid cascade as primary events (supported by the "beta-aptists") and cytoskeletal abnormalities secondary to the hyperphosphorylation of protein Tau (as advocated by the "Tauists"). We further provide an integrative view of the physiopathology of AD.

Resumo: A doença de Alzheimer (DA) é uma desordem neurodegenerativa progressiva que cursa comprometimento da memória e outras funções cognitivas, alterações comportamentais, psíquicas e da personalidade. Os achados neuropatológicos característicos da DA são as placas neuríticas (senis) e os emaranhados neurofibrilares, também ocorrendo distrofia de neuritos, gliose e perda neuronal. As placas neuríticas são lesões extracelulares que têm no peptídeo beta-amilóide (A beta42) seu principal constituinte. Os emaranhados neurofibrilares são lesões intraneuronais compostas por agregados de proteína TAU em estado hiperfosforilado. Neste artigo de revisão, apresentamos as principais hipóteses relacionadas à fisiopatologia da DA, com foco na cascata do amilóide como evento inicial (hipótese preconizada pelos "beta-aptistas") e nas alterações do citoesqueleto neuronal, decorrentes da fosforilação anormal da TAU (conforme proposto pelos "beta-tauístas"). Os achados são discutidos numa leitura integrada desses dois mecanismos fisiopatológicos.

Neurobiological pathways to Alzheimer's disease: Amyloid-beta, TAU protein or both?

Alzheimer's disease (AD) is a neurodegenerative disease characterized by progressive cognitive decline, including memory loss, behavioral and psychological symptoms and personality changes. The neuropathological hallmarks of AD are the presence of neuritic (senile) plaques (NP) and neurofibrillary tangles (NFT), along with neuronal loss, dystrophic neurites, and gliosis. Neuritic plaques are extracellular lesions and their main constituent is the amyloid-ß42 peptide (Aß42). Neurofibrillary tangles are intracellular lesions that are mainly composed of hyperphosphorylated Tau protein. In this article, we review the major hypotheses concerning the physiopathology of AD, focusing on the ß-amyloid cascade as primary events (supported by the "ßaptists") and cytoskeletal abnormalities secondary to the hyperphosphorylation of protein Tau (as advocated by the "Tauists"). We further provide an integrative view of the physiopathology of AD.

A doença de Alzheimer (DA) é uma desordem neurodegenerativa progressiva que cursa comprometimento da memória e outras funções cognitivas, alterações comportamentais, psíquicas e da personalidade. Os achados neuropatológicos característicos da DA são as placas neuríticas (senis) e os emaranhados neurofibrilares, também ocorrendo distrofia de neuritos, gliose e perda neuronal. As placas neuríticas são lesões extracelulares que têm no peptídeo beta-amilóide (Aß42) seu principal constituinte. Os emaranhados neurofibrilares são lesões intraneuronais compostas por agregados de proteína TAU em estado hiperfosforilado. Neste artigo de revisão, apresentamos as principais hipóteses relacionadas à fisiopatologia da DA, com foco na cascata do amilóide como evento inicial (hipótese preconizada pelos "ßaptistas") e nas alterações do citoesqueleto neuronal, decorrentes da fosforilação anormal da TAU (conforme proposto pelos "tauístas"). Os achados são discutidos numa leitura integrada desses dois mecanismos fisiopatológicos.

Hyptis pectinata essential oil: chemical composition and anti-Streptococcus mutans activity.

OBJECTIVES: The aim of the present study was to evaluate the anti-Streptococcus mutans activity of Hyptis pectinata essential oil, and present its promising potential against oral diseases. MATERIALS AND METHODS: The essential oil of H. pectinata was obtained by hydrodistillation from dried leaves and analyzed by GC / MS. The effectiveness of this essential oil regarding the antimicrobial activity against several S. mutans strains was investigated by the agar diffusion and microdilution methods, and chlorohexidine was used as a standard control. RESULTS: The H. pectinata essential oil exhibited considerable inhibitory effect against either all the clinical isolates obtained from patients' saliva or the ATCC strains tested, with minimum inhibitory and bactericidal concentrations of 200 microg ml(-1). The study also compared the efficiency of the emulsifying agents Tween 20, Tween 80, dimethyl sulfoxide and propylene glycol in H. pectinata essential oil when tested against S. mutans. The data obtained confirmed the better inhibitory effect of the oil when using all tested diluents, although Tween 80 seemed to be more suitable for emulsification. CONCLUSION: According to our results, H. pectinata essential oil can be considered a promising alternative to chlorhexidine for the control of oral bacteria-related diseases and hygiene.

Prevalence of inflammatory bowel disease in an insured population in Puerto Rico during 1996

OBJECTIVES: Limited data exists about Inflammatory Bowel Disease (IBD) in Hispanic populations. The aims of the present study were to estimate overall and specific prevalence of IBD (Crohn's disease and ulcerative colitis) and to describe the characteristics of a group of patients from the University of Puerto Rico's IBD Registry. METHODS: To estimate the prevalence of IBD, computerized records of all physician billing and hospital discharges from a major health insurer in Puerto Rico and classified with ICD-9-CM codes 555.0-555.9 (Crohn's disease) and 556.0-556.9 (ulcerative colitis) during 1996 were searched. Prevalence was estimated by age group, sex, and type of insurance. To describe demographic and selected clinical information from patients with IBD, data gathered in the University of Puerto Rico's IBD Registry from 1995 through 2000 was analyzed. RESULTS: Out of 802,726 insured individuals, 332 had a diagnosis of Crohn's disease, 499 of ulcerative colitis and 21 had both diagnoses. The estimated prevalence per 100,000 was 41.4 for Crohn's disease, 62.2 for ulcerative colitis, and 106.1 cases per 100,000 for IBD. Peak prevalence of Crohn's disease occurred among the age groups 50-59 years and > or = 60 years, and the overall female:male prevalence ratio of Crohn's disease was 1.13 (95 per cent CI: 0.91-1.42). Ulcerative colitis was most prevalent among insured individuals aged 50-59 years and 40-49 years. The prevalence of ulcerative colitis was significantly higher among females than among males, with an overall prevalence ratio of 1.42 (95 per cent CI: 1.18-1.71). Of 342 patients participating in the IBD Registry, 155 (45.3 per cent) had Crohn's disease and 187 (54.7 per cent) had ulcerative colitis. Among patients diagnosed with Crohn's disease, 51.6 per cent were females, the mean age was 35.2 +/- 18.3 years, and 18.1 per cent had a family history of IBD. More than half (57.8 per cent) of patients with ulcerative colitis were females, the mean age was 42.6 +/- 17 years, and 17.1 per cent had a family history of IBD. CONCLUSIONS: The estimated prevalence of IBD in this insured population in Puerto Rico places it among the middle-range of that reported for other countries. Additional studies must be conducted in Puerto Rico in order to confirm the observed findings. Population-based epidemiologic studies aimed at estimating the burden of IBD in Hispanic populations in the United States and Latin America are essential for health care planning.

Estudo biofarmacotécnico de cápsulas e comprimidos de diclofenaco sódico de liberaçäo modificada, disponíveis no mercado nacional: avaliaçäo da eficiência de dissoluçäo / Biopharmaceutical study of diclofenac sodium modified release capsules and tablets available in national market: evaluation of dissolution efficiency

Foram avaliadas as propriedades biofarmacêuticas in vitro de amostras provenientes de três fabricantes - A (cápsulas), B e C (comprimidos), três lotes de cada, contendo 100 mg de diclofenaco sódico de liberação modificada. Para cápsulas e comprimidos foram realizados ensaios de peso médio, desintegração, uniformidade de conteúdo, teor e perfil de dissolução e também de dureza para comprimidos. O fármaco foi quantificado por espectrofotometria no UV a 278 nm. Apenas os lotes A3, B1 e B2 atenderam aos limites especificados para o teor (85 a 115 por cento). Os produtos A e B liberaram, após seis horas de ensaio, porcentagens do fármaco abaixo das especificações descritas na literatura, que se confirmam na eficiência de dissolução...

Analysis of the antinociceptive properties of marrubiin isolated from Marrubium vulgare.

We have shown previously that Marrubium vulgare, a medicinal plant employed frequently in folk medicine to treat a variety of ailments, exhibits antispasmodic and antinociceptive effects in different experimental models. This work describes the antinociceptive profile of marrubiin, the main constituent of this plant, which was analysed in some models of nociception in mice. The results showed that marrubiin exhibits potent and dose-related antinociceptive effects, whose calculated ID50 values (micromol/kg, i.p.) were the following: 2.2 in the writhing test, 6.6 (first phase) and 6.3 (second phase) in the formalin-induced pain test and 28.8 when evaluated in the capsaicin test. It was more potent than some well-known analgesic drugs. The antinociception produced by the marrubiin was not reversed by naloxone when analyzed against the writhing test. In the hot-plate test, marrubiin did not increase the latency period of pain induced by the thermal stimuli. Its exact mechanism of action remains to be determined, but the results suggest that marrubiin, like hydroalcoholic extract of M. vulgare, does not interact with opioid systems.

Estudo comparativo do perfil de dissolução de comprimidos de cloreto de potássio comercializados no Brasil / Comparative study of dissolution profile of potassium chloride tablets marketed in Brazil

Avaliou-se a dissolução de comprimidos de cloreto de potássio de dois fabricantes (A e B), comercializados no mercado farmacêutico brasileiro. Foi adotada metodologia descrita pela Farmacopéia Americana 23ª edição, 1995. Além do teste de dissolução, conforme preconizado por esta Farmacopéia, traçou-se, sob as mesmas condições, o perfil de dissolução dos produtos. Foram analisados, de cada fabricante, dois lotes distintos (A1, A2 e B1, B2). A determinação das concentrações de potássio dissolvido foram realizadas em fotômetro de chama. Os resultados indicaram discrepância entre os dois produtos: o laboratório A teve seus dois lotes rejeitados, de acordo com o teste de dissolução da USP23(1995), enquanto que o laboratório B não apresentou este tipo de problema...

Desenvolvimento e avaliação biofarmacotécnica de comprimidos de liberação controlada de cloridrato de metformina empregando meio de dissolução com variação gradual de pH / Development and biopharmaceutical evaluation of controlled release tablets of metformin hydrochloride using dissolution medium with gradual pH variation

Quatro formulações de comprimidos de liberação controlada contendo 850 mg de cloridrato de metformina foram preparadas variando-se as quantidades do polímero hidroxipropilmetilcelulose (HPMC K100) e de ácido esteárico. Estas preparações foram submetidas a ensaios de dissolução sob as seguintes condições experimentais: equipamento utilizado: aparelho de dissolução com seis cubas; meios de dissolução: meio com variação gradual de pH (1,3 a 7,5) e água desgaseificada; volume do meio de dissolução: 1000 mL; sistema de agitação: pá; velocidade de agitação: 100 rpm; temperatura: 37,0ñ0,5 ºC; volume de coleta e reposição do meio: 10 mL, nos intervalos de tempo de 10, 30, 60, 90, 120, 180, 240, 300 e 360 minutos. O fármaco foi quantificado por espectrofotometria no ultravioleta a 233 nm...