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This work aims to develop safety shoes, with thermal regulation systems, namely innovative heating and cooling systems. Heating system was developed using printing techniques; and cooling system was developed using the integration of Peltier modules in the shoe structure. These materials are based on the Peltier effect, in which, when an electric current is applied, the heat moves from one face to the other, being subsequently removed using thermal dissipation methods. This effect allows an active cooling. Given the high technological challenge of integrating cooling systems into footwear, this paper will present only developments related to cooling system.

Administration of active pharmaceutical ingredients (APIs) through the skin, by means of topical drug delivery systems, is an advanced therapeutic approach. As the skin is the largest organ of the human body, primarily acting as a natural protective barrier against permeation of xenobiotics, specific strategies to overcome this barrier are needed. Liposomes are nanometric-sized delivery systems composed of phospholipids, which are key components of cell membranes, making liposomes well tolerated and devoid of toxicity. As their lipid compositions are similar to those of the skin, liposomes are used as topical, dermal, and transdermal delivery systems. However, permeation of the first generation of liposomes through the skin posed some limitations; thus, a second generation of liposomes has emerged, overcoming permeability problems. Various mechanisms of permeation/penetration of elastic/ultra-deformable liposomes into the skin have been proposed; however, debate continues on their extent/mechanisms of permeation/penetration. In vivo bioavailability of an API administered in the form of ultra-deformable liposomes is similar to the bioavailability achieved when the same API is administered in the form of a solution by subcutaneous or epi-cutaneous injection, which demonstrates their applicability in transdermal drug delivery., This research was funded by the Portuguese Science and Technology Foundation (FCT/ MCT) and European Funds (PRODER/COMPETE), under the project reference UIDB/04469/2020 (strategic fund), co-financed by FEDER, under the Partnership Agreement PT2020. The work is also supported by the National Science Centre within the MINIATURA 4 for a single research activity (grant No: 2020/04/X/ST5/00789) and by the START 2021 Program of the Foundation for Polish Science (FNP) granted to Aleksandra Zielinska., info:eu-repo/semantics/publishedVersion

Background Postural instability is a possible symptom in children with otitis media, which often occurs in this population. The child with balance disorders usually has intolerance to sudden movements, difficulties in moving in the dark, nausea, vomiting and numerous fall events. To verify whether changes in the middle ear can influence the balance postural in children from 3 to 5 years. Methods The sample consisted of 31 children of both sexes, aged between 3 and 5 years. To collect data, a tympanogram was used to analyze the integrity of the tympanic membrane and the Modifid Clinical Test of Sensory Integration and Balance (MCTSIB), with four different sensory conditions, to assess static postural balance. Results Regarding the tympanogram, it was verified that the majority of the sample showed no changes, 45.2% of which were type A and 32.3% of type C1. Regarding the type B and C2 tympanogram, it was found that 12.9% of the sample had type B tympanogram and 9.7% type C2. When comparing these values with the MCTSIB results, there were no significant differences between the tympanogram with changes (B and C2) and the tympanogram without changes (A and C1), regarding the child's balance performance. Conclusions In this study, it was concluded that the alterations of the middle ear, proved through the tympanogram, did not influence the postural balance. However, it was found that the unilateral changes reported by the tympanogram, suggest higher values of postural oscillation, compared to bilateral changes.

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Background: Impairment in speech perception is a common feature of older adults. This study aimed at evaluating the acute and sub-acute (after three months) effects of auditory training on central auditory processing in older people with hearing loss. Methods: A nonrandomized study was conducted enrolling 15 older adults with hearing loss and an average age of 78.6 &plusmn, 10.9 years. All participants underwent a baseline otoscopy, tympanogram, audiogram and speech-in-noise test with a signal-noise ratio (SNR) of 10 and 15 dB. Afterwards, auditory training intervention was implemented consisting of 10 training sessions over 5 weeks. Participants were divided into two groups: group 1 (G1) underwent auditory training based on a speech-in-noise test, group 2 (G2) underwent a filtered-speech test. Auditory processing was evaluated at baseline (T0) immediately after the intervention (T1) and 3 months after the intervention (T2). Results: Group 1 were quite efficient regardless of the SNR in the right ear with statistically significant differences from T0 to T1 (p = 0.003 and p = 0.006 for 10 dB and 15 dB, respectively) and T0 to T2 (p = 0.011 and 0.015 for 10 dB and 15 dB, respectively). As for the left ear, the increase of success was statistically significant for the SNR of 10 dB and 15 dB from T0 to T1 (p = 0.001 and p = 0.014, respectively) and from T0 to T2 (p = 0.016 and p = 0.003). In G2, there was a significant variation only from T0 for T1 in the left ear for an SNR of 10 dB (p = 0.001). Conclusion: Speech perception in noise significantly improved after auditory training in old adults.

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INTRODUÇÃO: A presbiacúsia acarreta dificuldades na interpretação do sinal sonoro com uma influência acrescida na perceção do discurso na presença de ruído. Pretende-se estudar as habilidades do processamento auditivo central na discriminação da fala no ruído, em pessoas idosas. MATERIAL E MÉTODOS: A amostra foi constituída por 20 sujeitos, com idades compreendidas entre os 67 e os 92 anos. Todos realizaram otoscopia, timpanograma, audiograma tonal simples e teste de fala no ruído. Este estudo é do tipo descritivo-correlacional e transversal. RESULTADOS: A curva audiométrica apresenta declínio significativo (p < 0,001) com o aumento das frequências testadas, a partir da frequência dos 500 Hz, apresentando o ouvido esquerdo melhores resultados do que o ouvido direito, com significância estatística (p = 0,043), apenas nos 250 Hz. No teste de fala no ruído, os resultados do ouvido esquerdo evidenciaram uma média de acertos de 21,5% na relação sinal/ruído de 10 dB, tendo um aumento significativo (p < 0,001) na relação sinal/ruído de 15 dB cuja média de acertos foi 26,3%. O ouvido direito exibe uma média de acertos de 17,3% e de 27,85% na relação sinal/ruído de 10 dB e de 15 dB respetivamente, com um aumento significativo (p = 0,002) na relação sinal/ruído de 15 dB. CONCLUSÃO: Tendo em conta os resultados, em que o teste de fala no ruído apresenta uma média de acertos inferior aos 50% em ambos os ouvidos, chegámos à conclusão que quanto menor for a relação sinal/ruído maiores as dificuldades na compreensão da fala. Assim, a avaliação audiológica da pessoa idosa deve incluir a avaliação periférica e central. INTRODUCTION: Presbycusis entails difficulties in the interpretation of the sound signal with an increased influence in perceiving speech in the presence of noise. We intend to study the central auditory processing skills in speech discrimination in noise of elderly people. METHODS: The sample consists of 20 people, aged from 67 to 92. All the people have undergone an otoscopy, a tympanogram, a pure tone audiogram and the speech in noise test. This is a descriptive-correlational study. RESULTS: The audiometric curve shows a statistically significant decline (p < 0.001) with increasing in the frequencies tested, from the frequency of 500 Hz. The left ear presents better results than the right ear, with statistical significance (p = 0.043), only at the frequency of 250 Hz. In the speech in noise test, the results from the left ear showed an average of 21.5% correct answers with a signal/noise relation of 10 dB, with a statistically significant increase (p < 0.001) with signal/noise relation of 15 dB, where the average of correct answers was 26,3%. For the right ear, we obtained an average of 17.3% and 27.85% of correct answers with a signal/noise relation of 10 dB and 15 dB, respectively. There was also a significant increase (p = 0.002) with a signal/noise relation of 15 dB. CONCLUSION: Considering that the speech in noise test exhibits a mean of less than 50% for both ears, we concluded that the smaller the signal/noise relation the greater the difficulties in understanding the speech. So the audiological evaluation of the elderly should include the peripheral and central evaluation. Aga@4life info:eu-repo/semantics/publishedVersion

Introduction: The hearing function is the cornerstone on which is built the complex system of human communication. The Acute Otitis Media is one of the most common etiologies of hearing loss in children attending school, mainly around 5 years of age. They appear asymptomatic so that only through auditory screening programs can we identify this type of situations early. So, if this type of hearing loss (though often small and temporary) occurs repeatedly, it can cause a negative impact on the auditory processing development, in the acquisition and development of language and in the school success of children. Aim: to determinate the prevalence of hearing loss among the Cape Verdean preschool children in comparison with Portuguese children of the same age and, consequently, to alert the importance of the hearing screening in preschool age. Methods: The sample consisted of 84 preschool children (5 and 6 years old): 42 Portuguese and 42 Cape Verdean. An anamnesis was performed on the parents and / or guardians of the children, an otoscopy, a tympanogram and a Pure Tone Audiogram screening ("pass / fail") at the frequencies of 1000Hz, 2000Hz and 4000Hz. Results: In the present study, no statistically significant differences were found in the results between children of both nationalities. Conclusion: In view of the findings of this study, and of the information acquired, it is important to emphasize that, in addition to dissemination and awareness raising, one of the proposals for Cape Verde is the implementation of neonatal screening programs, followed by the subsequent implementation of preschool and school screenings. It should also be implemented in Portugal in a systematic and obligatory way. info:eu-repo/semantics/publishedVersion

Background, the use of ototoxic drugs is common in patients with head and neck tumors. Consequently, there may be vestibular dysfunctions that are not always detected, affecting the quality of life. Thus, it is important to evaluate the factors that may lead to vestibular system dysfunction. The objective of this study is to determine if vestibular dysfunction in individuals with head and neck tumors who underwent chemotherapy and/or radiotherapy also occurred in a control group. Material and Methods, the sample consists of 54 individuals of both genders, aged between 20 and 91 years old and is divided into two groups: a group of 30 individuals without any kind of tumor and no medical history of chemotherapy and/or radiotherapy (control group) and a group of 24 individuals with head and neck tumors. The instruments used to collect the data were an Anamnesis, the modified Clinical Test of Sensory Interaction and Balance (mCTSIB), Limits of Stability test (LOS) and the Dizziness Handicap Inventory (DHI) scale. Results, there are statistically significant differences between the two groups on the Physical, Functional and Emotional sub-scales of the DHI scale, on the DHI Total (p DHI Physical < 0,0001; p DHI Functional < 0,0001; p DHI Emotional < 0,0001; p DHI Total < 0,0001) and on the Reaction Time (RT) in LOS test in every position (p RT Front = 0,020, p RT Back = 0,011, p RT Right = 0,036, p RT Left = 0,036). There are marginally significant differences between the two groups in the postural oscillation velocity in Condition 4 of the mCTSIB (p Condition 4 = 0,065). Conclusion, the group of individuals with head and neck tumors had worse results on the DHI scale, in the RT in LOS test and in the Condition 4 of the mCTSIB, suggesting the existence of greater vestibular alterations in this group compared to the control group. info:eu-repo/semantics/publishedVersion

Background, Stuttering is a disturbance of language that affects 1% of the adult population and about one hundred thousand Portuguese people. This speech disturbance may show changes in the processing of information received through the sense of hearing. After several theories, the need to evaluate neurophysiological processes in individuals with stuttering arises and in this sense, electrophysiological tests can be used. Material and methods, The sample consisted of 10 individuals with stuttering (study group), and 10 fluent individuals (control group), with an age range between 19 to 57. All subjects have undergone an otoscopy, tympanogram and a research of the Stapedial Reflex in 1000 Hz and 2000 Hz frequency, pure tone audiogram screening (pass-fail) at the frequencies of 1000 Hz, 2000 Hz and 4000 Hz. To collect the electrophysiological responses (P300), we used some inclusion criteria, such as being aged between 18 to 60, speaking the European Portuguese, without diagnosis of psychiatric and/or neurological alterations, otoscopy without alterations, the Tympanogram being of type A or C1 and getting response up to 40 dB in the frequencies 1000 Hz, 2000 Hz and 4000 Hz in the pure tone audiogram screening. Then, every subject did the evoked auditory potential of long latency (P300). Results, There were statistically significant differences (p = 0.005) between the right ear latency values in subjects with stuttering (347.10 ms ± 18.24) compared to fluent individuals (315.80 ms ± 22.51). In the left ear there were also statistically significant differences (p = 0.023) in mean values of latencies that were higher in stutterers (344 ms ± 32.50) compared to fluent individuals (311 ms ± 20.75). Conclusion, In this study it was verified a change in the electrophysiological response of the P300 in individuals with stuttering. Although the values of latency are within the normal range, in both groups (300-400ms) the individuals with stuttering need more time to process and discriminate auditory stimuli. info:eu-repo/semantics/publishedVersion

Com o envelhecimento, ocorrem alterações na perceção e deteção do som no sistema auditivo com repercussões no processo de comunicação. O estudo da audição no idoso deve incluir a avaliação do sistema auditivo central e periférico com a adequação de técnicas comportamentais e eletrofisiológicas para a avaliação do Processamento Auditivo Central, com vista à implementação de programas de treino. Vários estudos sugerem que este seja realizado para minimizar as dificuldades de compreensão da fala, principalmente em ambientes ruidosos de modo a que as lacunas no processamento da informação sejam reduzidas e que a identificação e discriminação dos padrões sonoros sejam potencializados. O treino auditivo pode ser aplicado em diferentes faixas etárias, sendo uma excelente opção para indivíduos com hipoacúsia, utilizadores de aparelhos auditivos e idosos com dificuldades na compreensão da fala. O objetivo deste estudo é avaliar o efeito do treino auditivo nas capacidades da compreensão da fala em idosos. AGA@4life info:eu-repo/semantics/publishedVersion

CENTRO-01-0145-FEDER-023369 2017-2019 info:eu-repo/semantics/publishedVersion

Topical administration of drugs presents some advantages over other routes; the drug can be administered in the anatomical region to be treated, limiting the systemic distribution and side effects. However, the structure of the skin makes it a highly effective barrier to drug permeation. Amongst the strategies to overcome this obstacle, liposomes are interesting vehicles for delivering the drugs into the skin, the synovial cavity or other regions affected by inflammatory or degenerative conditions. Liposomes are lipid carriers of nanometric size formed by phospholipid bilayers. They have the advantages of preparation feasibility and biological compatibility associated with the possibility of carrying either lipophylic and/or hydrophylic compounds, and have been extensively used in various drug delivery systems, for drug targeting, controlled release and permeation enhancement of drugs. Conventional liposomes are not very stable and not suitable for dermal administration after topical application, since they accumulate on the skin surface due to the rigidity of the lipid layers and suffer dehydration, culminating in their fragmentation. Other formulations have emerged in the meantime, such as transfersomes, niosomes or ethosomes. The present work consists of a review on the published scientific papers regarding the development of liposomal formulations containing non-steroidal anti-inflammatory drugs for the purpose of relieving the symptomatology of inflammatory and degenerative ailments. The exposition summarizes data relating to liposome type, composition, preparation method, liposome characterization, topical vehicle used, in vitro permeation studies performed, in vivo anti-inflammatory assays carried out and results obtained in the different studies published in the last five years.

This work presents a comparative study of the interaction of three porphyrins: the cationic meso-tetra(4-N,N,N-trimethylanilinium) porphine tetrachloride (T973); the anionic meso-tetra(4-carboxyphenyl) porphine (T790); and the neutral meso-tetra(p-hydroxyphenyl) porphine (T679) with model membranes, at two different pH values. The models for the biological membrane used were micelles of hexadecylphosphocholine and large unilamellar liposomes of egg yolk phosphatidylcholine. The liposome–buffer partition coefficients (K) were determined by derivative spectrophotometry at two different pH values (7.4 and 5.8), in order to mimic plasma and tumor tissue conditions, respectively. Different types of partition were observed for different molecules, systems and pH values. Theoretical mathematical models, which accounted for the stoichiometry of the interaction, were used to fit the experimental data and determine the value of K. The values of K obtained are important in the choosing of a promising light-sensitizing agent to be used in photodynamic therapy for cancer treatment, since this parameter governs the distribution of the drug in the organism and the amount of drug that can be found on the site of irradiation.

Birth is an event that exposes the newborn baby to a high concentration of free radicals (reactive oxygen species (ROS)/reactive nitrogen species (RNS)), which can contribute to several diseases. The balanced equilibrium between ROS/RNS and the antioxidant system of the newborn is a key factor in preventing a plethora of diseases. The antioxidant system involves endogenous and exogenous molecules, from vitamins (A, E, C) to enzymes (glutathione peroxidase, superoxide dismutase), metals (copper, zinc, and selenium) and other molecules (coenzyme Q10, melatonin) that can act in a synergistic manner to deactivate free radicals. A competent antioxidant system of the baby is strongly dependent on the intake of free radical deactivating molecules from feeding, either maternal or formula milk, with several studies pointing that breast milk has more powerful antioxidant effects on lowering the infant's oxidative status. An improved understanding of the antioxidant molecules, their mechanism of action, and the relationships between them, are key factors to comprehend all the potential benefits of human breastfeeding in this matter. The purpose of this review is to describe different research efforts and methodologies of evaluation of TAS in human milk, and to evaluate and summarize the contribution of different antioxidant molecules.

Submitted by Christianne Fontes de Andrade (cfontes@ct.ufrj.br) on 2019-06-05T16:56:53Z No. of bitstreams: 1 876744.pdf: 3514601 bytes, checksum: 6b700ee53bb99188bbe11052c806a1b3 (MD5) Made available in DSpace on 2019-06-05T16:56:53Z (GMT). No. of bitstreams: 1 876744.pdf: 3514601 bytes, checksum: 6b700ee53bb99188bbe11052c806a1b3 (MD5) Previous issue date: 2017-12 O poli(fluoreto de vinilideno) (PVDF) é um polímero que vem despertando o interesse da indústria de óleo e gás por ser impermeável a gases/líquidos, inerte a maior parte das espécies químicas e por ser estável a altas temperaturas/pressões. Como ainda é desconhecido a existência de um processo de reciclagem desse fluorpolímero, o seu resíduo de produção é destinado a aterros, impactando o meio ambiente uma vez que este não é biodegradável. Uma solução proposta é a reinserção do resíduo pós-industrial de PVDF na indústria de transformação desse termoplástico de engenharia por meio da reciclagem primária, misturando o resíduo pós-industrial com o material virgem comercial. Os resultados de FTIR mostraram que o resíduo pós-industrial de PVDF, o material comercial e os reciclados (95/5, 80/20 e 50/50 %mássica) apresentam coexistência de fases α e β tanto antes quanto após o envelhecimento térmico. As condições utilizadas no envelhecimento térmico foram responsáveis por provocar a termo-oxidação dos materiais analisados levando a uma cristalização secundária, detectada por DRX. A termo-oxidação não foi suficiente para promover mudanças significativas na estabilidade térmica assim como nas propriedades mecânicas dos materiais reciclados e do resíduo pós-industrial de PVDF. Poly(vinylidene fluoride) (PVDF) is a polymer widely used by the oil & gas industry due to its special features that make it suitable for this application, like imperviousness to liquid and gases, good compatibility with most chemicals and good stability in high pressure/temperature. As a recycling process for this fluoropolymer is still unknown, this work suggests reinserting the PVDF post-industrial waste by primary recycling aiming the remediation of the issue caused by its disposal in the environment. Results showed that both PVDF post-industrial and recycled ones present in its microstructures coexistence of alfa end beta phase. The thermal aging was responsible for promoting thermo-oxidation in the samples which lead to secondary crystallization, however, this secondary crystallization did not affect significantly the materials thermal stability and mechanical properties, making both recycled PVDF and post-industrial PVDF waste promising.

The aims of this paper were to evaluate changes in specific oligoelements in human milk during the first four months of lactation and to correlate such changes with total antioxidant status (TAS) and other parameters, such as the mother's age, primipara versus multipara, and supplement intake. Milk samples were collected from 31 lactating women following 1, 4, 8, 12 and 16 weeks after birth. Trace levels of 13 elements were measured by inductively coupled plasma-mass spectrometry (ICP-MS). The results obtained for the oligoelements exhibited a decrease in concentration from 7 days to 4 months of breast-feeding, with exceptions. Correlations were found between TAS and Co, V, Rb and Tl. Between primipara and multipara, differences were found for Ni and Rb. Regarding the mother's age, correlation was found for Rb and Ba (increased for mothers older than 30 years). Increased amounts of Rb, Mo and Tl at any lactation period appeared in women who took supplements.

Lactoferrin has for long captured the interest of many researchers as a natural compound with a wide variety of uses. Lactoferrin is a monomeric, iron-binding 80 kDa glycoprotein, and appears to be the subfraction of whey with the best documented antiviral, antimicrobial, anticancer and immune modulating/enhancing effects. It belongs to the family of transferrin proteins, and serves to control iron levels in body fluids by sequestering and solubilizing ferric iron. In the present research effort, production of lactoferrin derivatives (starting from a purified commercial extract), encompassing full stabilization of its three-dimensional structure, has been attempted via nanoencapsulation within lipid nanovesicles, integrating a multiple water-in-oil-in-water emulsion. Long-term storage of the multiple nanoemulsions produced did not lead to leaching of protein, thus proving the effectiveness of the encapsulation procedure. Furthermore, lactoferrin nanovesicle derivatives prepared under optimal conditions were successfully employed at lab-scale antimicrobial trials., Financial support from Fundacao Ensino e Cultura Fernando Pessoa (FECFP, Porto, Portugal) and from Fundacao para a Ciencia e a Tecnologia (FCT, Lisbon, Portugal) as pluriannual funding, is gratefully acknowledged. Financial support to Victor M. Balcao, via an Invited Research Scientist fellowship (FAPESP Ref. No. 2011/51077-8) by Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP, Sao Paulo, Brazil), is hereby gratefully acknowledged. The authors are also grateful to Dr. Madalena Vieira (affiliated with the IBB) for technical help.

Summary Objective: Translate, transcultural adaptation and application to Brazilian Portuguese of the Alzheimer’s Disease Cooperative Study - Activities of Daily Living (ADCS-ADL) scale as a cognitive screening instrument. Method: We applied the back translation added with pretest and bilingual methods. The sample was composed by 95 elderly individuals and their caregivers. Thirty-two (32) participants were diagnosed as mild cognitive impairment (MCI) patients, 33 as Alzheimer’s disease (AD) patients and 30 were considered as cognitively normal individuals. Results: There were only little changes on the scale. The Cronbach alpha coefficient was 0.89. The scores were 72.9 for control group, followed by MCI (65.1) and by AD (55.9), with a p-value < 0.001. The ROC curve value was 0.89. We considered a cut point of 72 and we observed a sensibility of 86.2%, specificity of 70%, positive predictive value of 86.2%, negative predictive value of 70%, positive likelihood ratio of 2.9 and negative likelihood ratio of 0.2. Conclusion: ADCS-ADL scale presents satisfactory psychometric properties to discriminate between MCI, AD and normal cognition. Resumo Objetivo: Tradução, adaptação transcultural para o português brasileiro e aplicação da escala Alzheimer’s Disease Cooperative Study - Activities of Daily Living (ADCS-ADL) como instrumento de triagem cognitiva. Método: Retrotradução associada ao método bilíngue e de pré-teste. A amostra foi constituída por 95 idosos e seus respectivos acompanhantes, sendo 30 controles, 32 portadores de comprometimento cognitivo leve (CCL) e 33 portadores de demência de Alzheimer (DA) em fase inicial. Resultados: Um pequeno número de modificações ocorreu na escala. O coeficiente alpha de Cronbach foi 0,89. O grupo controle pontuou 72,9, seguido pelo CCL (65,1) e pelo DA (55,9), valor p

Hepatocellular carcinoma (HCC) is the sixth most common cancer in the world in terms of incidence, accounting for approximately 630 thousand new cases per year; in addition, HCC is the third most common cause of cancer death. Worldwide, the greatest risk factors for HCC are the infections caused by hepatitis B and C viruses, which increase the risk of developing the disease by about 20 times. The standard treatment in the early stages of the disease, such as surgical resection, local ablation and liver transplantation, are able to cure a proportion of patients, but most cases of HCC present in advanced stages, precluding the use of such treatments with curative intent. In these advanced stages, systemic treatments are commonly used. Unfortunately, chemotherapy with conventional cytotoxic agents is ineffective and does not seem to modify the natural history of disease. Treatment options for patients with advanced HCC are extremely limited, but the identification of signaling pathways, and the recognition of the role of these pathways in the pathogenesis of the disease resulted in the development of drugs directed at specific therapeutic targets. One such drug is Sorafenib, a kinase inhibitor with antiangiogenic and antiproliferative properties. In conclusion, Sorafenib has demonstrated survival benefits in patients with advanced HCC, thus representing a new standard reference for systemic treatment in these cases.

Background: Patients with end-stage renal disease (ESRD) undergoing hemodialysis are a risk group for hepatitis C virus (HCV) infection. The characteristics of acute hepatitis C infection in this population are not well known. Goals: To evaluate the clinical and laboratory characteristics of acute hepatitis C in ESRD patients treated with hemodialysis. Study: ESRD patients on hemodialysis with acute hepatitis C, characterized by elevated alanine aminotransferase (ALT) followed by anti-HCV seroconversion were studied. Results: Thirty-six patients (58% females, 44 ± 12y), with a mean time on hemodialysis of 2 years, were included. Only 2 (6%) patients had jaundice. ALT elevation was observed in all patients. Median peak ALT was 4.7 x upper limit of normal. The median interval between ALT elevation and anti-HCV seroconversion was 1 month (0 to 8). None of the patients with detectable HCV-RNA showed spontaneous clearance of viremia within 12 weeks of follow-up. Three (8%) patients presented ALT elevation followed by anti-HCV seroconversion with undetectable HCV-RNA. Conclusions: Acute hepatitis C is frequently asymptomatic in ESRD patients on hemodialysis and should be suspected in all patients presenting elevated ALT. Determination of HCV-RNA is important for the confirmation of infection. Anti-HCV seroconversion seems to occur early and spontaneous clearance of HCV-RNA is uncommon.

In this work the interaction of a non-steroidal anti-inflammatory drug (NSAID), diclofenac, with egg yolk phosphatidylcoline (EPC) liposomes, used as cell-membrane models, was quantified by determination of the partition coefficient. The liposome/aqueous phase partition coefficient was determined by derivative spectrophotometry, fluorescence quenching, and measurement of zeta-potential. Theoretical models based on simple partition of the diclofenac between two different media, were used to fit the experimental data, enabling the determination of K(p). The three techniques used yielded similar results. The effects of the interaction on the membrane's characteristics were further evaluated, either by studying membrane potential changes or by effects on membrane fluidity. The liposome membrane potential and the size and size-homogeneity of liposomes were measured by light scattering. The effects of diclofenac on the internal viscosity or fluidity of the membrane were determined by use of spectroscopic probes-a series of n-(9-anthroyloxy) fatty acids in which the carboxyl terminal group is located at the interfacial region of the membrane and the fluorescent anthracene group is attached at different positions along the fatty acid chain. The location of the diclofenac on the membrane was also evaluated, by fluorescence quenching using the same series of fluorescent probes. Because the fluorescent anthracene group is attached at different positions along the fatty acid chain, it is possible to label at a graded series of depths in the bilayer. The interactions between the drug and the probe are a means of predicting the location of the drug on the membrane.