Colorectal cancer cell exosome and cytoplasmic membrane for homotypic delivery of therapeutic molecules

Colorectal cancer (CRC) is one of the most common causes of death in the world. The multi-drug resistance, especially in metastatic colorectal cancer, drives the development of new strategies that secure a positive outcome and reduce undesirable side effects. Nanotechnology has made an impact in addressing some pharmacokinetic and safety issues related to administration of free therapeutic agents. However, demands of managing complex biointerfacing require equally complex methods for introducing stimuli-responsive or targeting elements. In order to procure a more efficient solution to the overcoming of biological barriers, the physiological functions of cancer cell plasma and exosomal membranes provided the source of highly functionalized coatings. Biomimetic nanovehicles based on colorectal cancer (CRC) membranes imparted enhanced biological compatibility, immune escape and protection to diverse classes of therapeutic molecules. When loaded with therapeutic load or used as a coating for other therapeutic nanovehicles, they provide highly efficient and selective cell targeting and uptake. This review presents a detailed overview of the recent application of homotypic biomimetic nanovehicles in the management of CRC. We also address some of the current possibilities and challenges associated with the CRC membrane biomimetics.

Validation of 3-day rainfall forecast at the regional scale

Nearly half of the natural disasters in the world are due to hydro-geomorphological hazards. Therefore, rainfall forecast is a key parameter for the implementation of landslides and flash-floods early warning systems. In this work we developed a routine in R software that enables the validation of a 3-day rainfall forecast by comparison with the daily rainfall data recorded in 101 automatic meteorological stations available in mainland Portugal. The routine integrates the pre-processing of base data, the matching between the 3-day rainfall forecast and the daily rainfall registered in the automatic meteorological stations based on sequence of days, the estimation of the difference between the forecasted and the real rainfall values and the computation of error measures, such as the bias, the mean absolute error, the mean absolute percentage error and the root mean square error. The results from the error measures, estimated for the 101 automatic meteorological stations, are then exported to an excel file. The routine is implemented for mainland Portugal and tested using data from February 2015, however, the spatial and temporal data can be easily updated for other regions.•A routine to validate the rainfall forecast at the regional scale using R programming language is implemented.•The automated routine can be easily updated and adapted with different spatial and temporal scales.

Anxiety and need for support of college students during the SARS-CoV-2 pandemic: An exploratory study

Introduction

During the pandemic state, college students are exposed to additional stressful factors, including but not limited to: fear of being infected; fear of infecting a significant person; deal with a new reality of economic uncertainty; challenges of distance education; new rules in face-to-face classes; restrictions on access to internships and higher demanding in internships.

Objectives

This exploratory study aims to assess levels of anxiety and the perception of the need for support of students of a Portuguese Higher Education Institution (HEI).

Methods

An exploratory study was developed, on the return of students to the presential classes after the academic lockdown. It was spread out an email for all students with a link for an online form, which includes sociodemographic questions, a screening question of the anxiety level, and the need for support level (rating scales 0-10).

Results

It was obtained 36 answers from mostly female students (92%) with 17 to 21 years old (67%). Answers present an average anxiety level of 5.4 (Min=1; Max=9; SD=2.23), with 58% of answers with a score of anxiety level of 5 or higher. The need for support average was 3.7 (Min=1; Max=9; SD=2.23), with 33% of answers with a score of 5 or higher.

Conclusions

It is necessary to continuously monitor the anxiety level and the need for support of college students during the SARS-Cov-2 pandemic. It is similarly relevant to have responses of HEI to promote mental health and to answer to the high levels of students’ anxiety and needs for support during the pandemic.

Defining evacuation travel times and safety areas in a debris flow hazard scenario

Debris flows are one of the most hazardous types of landslides in mountain regions. In the upper part of the Zêzere valley (Serra da Estrela, Portugal) several debris flows events occurred in the last 200 years, some of them causing loss of lives and material damages. In this work, a methodology for pedestrian evacuation modelling, in a debris flow hazard scenario, was implemented. A dynamic run-out model, developed in previous studies, was used to evaluate the debris flows velocities, thickness of the deposits and extent of the mobilized material. The buildings potentially affected by the impact of debris flows were identified and the potentially exposed population was estimated by applying a dasymetric distribution. The results lead to the conclusion that, in the study area, the elderly are those who are most exposed to debris flows. Furthermore, the time lapse between the debris flows initiation and the arrival at the buildings at risk was estimated, allowing to account for the overall number of buildings where the evacuation time takes longer than the debris flows arrival. Additionally, the safe areas within the study area were identified, and several safe public buildings with the capacity to gather a large number of persons were selected. Considering that the study area is located in a mountain region, characterized by steep slopes, the evacuation modelling was performed based on an anisotropic approach, in order to consider the influence of slope direction on travel costs. At the end, three pedestrian evacuation travel time scenarios, based on different walking speeds to accommodate residents with different ages in safer places, were compared and the results mapped. The implemented methodology is not local dependent, which allows its reproduction elsewhere.

Orthorexia nervosa and comorbid depression successfully treated with mirtazapine: a case report

Orthorexia nervosa (ON) is a recently proposed eating disordered behaviour characterized by an obsessional or exaggerated fixation on healthy eating. The published literature is scarce regarding its classification, clinical presentation, management and long-term outcomes. Herein, we present the clinical and follow-up findings of an 18-year-old woman with ON comorbid with depression, successfully treated with mirtazapine. The patient had a 12-month history of obsessional behaviours for "healthy food", characterized by suppression of sugar and fat from her diet, tightly counted meal calorie content, eating only self-made meals, avoidance of eating in public, unacceptance of other person's opinions on diet, social isolation and a weight loss of 15 kg (body mass index of 16.2 kg/m²). A score of 19-points was initially obtained on the ORTO-15 questionnaire, suggesting the presence of orthorexic tendencies and behaviours. The patient also reported a 1-month history of depressed mood, anxiety, anhedonia, fatigue, insomnia with early morning waking, leading to the presumptive diagnosis of ON with comorbid depression. Treatment with mirtazapine for 11 months resulted in the remission of the disordered eating behaviour, a sustained regain of weight, a score of 41-points on the ORTO-15, and to the resolution of depressive symptomatology (including insomnia). To our knowledge, this is the first description of ON with comorbid depression successfully treated with mirtazapine. This case highlights the possible usefulness of mirtazapine as a treatment option for patients with ON. However, randomized controlled studies are warranted to confirm the current findings.

Portuguese consensus document for the management of alpha-1-antitrypsin deficiency

Alpha-1-antitrypsin deficiency (AATD) is a genetic autosomal codominant disorder caused by mutations in SERPINA1 gene. It is one of the most prevalent genetic disorders, although it remains underdiagnosed. Whereas at international level there are several areas of consensus on this disorder, in Portugal, inter-hospital heterogeneity in clinical practice and resources available have been adding difficulties in reaching a diagnosis and in making therapeutic decisions in this group of patients. This raised a need to draft a document expressing a national consensus for AATD. To this end, a group of experts in this field was created within the Portuguese Pulmonology Society - Study group on AATD, in order to elaborate the current manuscript. The authors reviewed the existing literature and provide here general guidance and extensive recommendations for the diagnosis and management of AATD that can be adopted by Portuguese clinicians from different areas of Medicine. This article is part of a supplement entitled "Portuguese consensus document for the management of alpha-1-antitrypsin deficiency" which is sponsored by Sociedade Portuguesa de Pneumologia.

Characterization of the fungitoxic activity on Botrytis cinerea of the aristolochic acids I and II

The fungitoxic effect of aristolochic acids I and II on mycelial growth and conidial germination of Botrytis cinerea was analysed. Aristolochic acid I had a higher effect on mycelial growth of B. cinerea than aristolochic acid II with IC₅₀ value of 18·7 and 57·0 μg ml^-1 , respectively. These compounds did not affect the conidia germination. Also, the effect of both compounds on DNA and plasmatic membrane integrity of B. cinerea was studied. Only aristolochic acid II was able to cause damage to the integrity of the plasmatic membrane. When the fungus was incubated with a mixture of these compounds, degradation of DNA was observed. Finally, biotransformation products were not detected in the culture broth when B. cinerea was incubated in the presence of the aristolochic acids. Studies of structural characteristics that increase the antifungal effect of compounds against B. cinerea will permit to design new molecules to control this phytopathogenic fungus. SIGNIFICANCE AND IMPACT OF THE STUDY: The fungitoxic effect on Botrytis cinerea of aristolochic acids I and II was characterized. The only structural difference among these compounds is a methoxy group at carbon 8. However, despite their structural similarity, the fungitoxic effect of aristolochic acid I was higher than the effect of aristolochic acid II. This result suggests that the methoxy group is important for the fungitoxic activity of these compounds on B. cinerea.

Ultrathin Monolithic Zirconia Veneers: Reality or Future? Report of a Clinical Case and One-year Follow-up

Yttria-stabilized polycrystalline zirconia ceramics have greatly advanced over the past few years. High-translucent zirconia is a newly introduced ceramic that affords high strength and esthetics and that has significantly increased the clinical indications of monolithic zirconia restorations. Thus, the purpose of this case report was to evaluate the performance of ultrathin monolithic zirconia veneers adhesively luted to enamel surfaces after minimally invasive preparations; in addition, we aimed at presenting a clinical protocol for zirconia surface treatment in order to promote bonding effectiveness to resin cement. This type of restoration presented very acceptable esthetic results and decreased the risk of fracturing the veneer during try-in and clinical use. The results were still satisfactory after one-year follow-up. However, randomized, prospective, controlled clinical trials are required to determine the long-term clinical durability of this treatment.

Mapping landslide susceptibility using data-driven methods

Most epistemic uncertainty within data-driven landslide susceptibility assessment results from errors in landslide inventories, difficulty in identifying and mapping landslide causes and decisions related with the modelling procedure. In this work we evaluate and discuss differences observed on landslide susceptibility maps resulting from: (i) the selection of the statistical method; (ii) the selection of the terrain mapping unit; and (iii) the selection of the feature type to represent landslides in the model (polygon versus point). The work is performed in a single study area (Silveira Basin - 18.2km² - Lisbon Region, Portugal) using a unique database of geo-environmental landslide predisposing factors and an inventory of 82 shallow translational slides. The logistic regression, the discriminant analysis and two versions of the information value were used and we conclude that multivariate statistical methods perform better when computed over heterogeneous terrain units and should be selected to assess landslide susceptibility based on slope terrain units, geo-hydrological terrain units or census terrain units. However, evidence was found that the chosen terrain mapping unit can produce greater differences on final susceptibility results than those resulting from the chosen statistical method for modelling. The landslide susceptibility should be assessed over grid cell terrain units whenever the spatial accuracy of landslide inventory is good. In addition, a single point per landslide proved to be efficient to generate accurate landslide susceptibility maps, providing the landslides are of small size, thus minimizing the possible existence of heterogeneities of predisposing factors within the landslide boundary. Although during last years the ROC curves have been preferred to evaluate the susceptibility model's performance, evidence was found that the model with the highest AUC ROC is not necessarily the best landslide susceptibility model, namely when terrain mapping units are heterogeneous in size and reduced in number.

Assessment of water pollution in the Brazilian Pampa biome by means of stress biomarkers in tadpoles of the leaf frog Phyllomedusa iheringii (Anura: Hylidae)

The Brazilian Pampa biome is currently under constant threat due to increase of agriculture and improper management of urban effluents. Studies with a focus on the assessment of impacts caused by human activities in this biome are scarce. In the present study, we measured stress-related biomarkers in tadpoles of the leaf frog Phyllomedusa iheringii, an endemic species to the Pampa biome, and tested its suitability as a bioindicator for the assessment of potential aquatic contamination in selected ponds (S1 and S2) nearby agricultural areas in comparison to a reference site. A significant decrease in acetylcholinesterase activity was observed in S2 when compared to S1 and reference. The levels of total-hydroperoxides were increased in S2 site. In parallel, increased activity of the antioxidant enzymes catalase, superoxide dismutase and glutathione S-transferase were observed in S2 when compared to S1 and reference. Further studies are necessary in order to correlate the changes observed here with different chemical stressors in water, as well as to elucidate mechanisms of toxicity induced by pesticides in amphibian species endemic to the Pampa biome. Nevertheless, our study validates Phyllomedusa iheringii as a valuable bioindicator in environmental studies.

Effects of gamma radiation on raspberries: safety and quality issues

There is an ever-increasing global demand from consumers for high-quality foods with major emphasis placed on quality and safety attributes. One of the main demands that consumers display is for minimally processed, high-nutrition/low-energy natural foods with no or minimal chemical preservatives. The nutritional value of raspberry fruit is widely recognized. In particular, red raspberries are known to demonstrate a strong antioxidant capacity that might prove beneficial to human health by preventing free radical-induced oxidative stress. However, food products that are consumed raw, are increasingly being recognized as important vehicles for transmission of human pathogens. Food irradiation is one of the few technologies that address both food quality and safety by virtue of its ability to control spoilage and foodborne pathogenic microorganisms without significantly affecting sensory or other organoleptic attributes of the food. Food irradiation is well established as a physical, nonthermal treatment (cold pasteurization) that processes foods at or nearly at ambient temperature in the final packaging, reducing the possibility of cross contamination until the food is actually used by the consumer. The aim of this study was to evaluate effects of gamma radiation on raspberries in order to assess consequences of irradiation. Freshly packed raspberries (Rubus idaeus L.) were irradiated in a (60)Co source at several doses (0.5, 1, or 1.5 kGy). Bioburden, total phenolic content, antioxidant activity, physicochemical properties such as texture, color, pH, soluble solids content, and acidity, and sensorial parameters were assessed before and after irradiation and during storage time up to 14 d at 4°C. Characterization of raspberries microbiota showed an average bioburden value of 10(4) colony-forming units (CFU)/g and a diverse microbial population predominantly composed of two morphological types (gram-negative, oxidase-negative rods, 35%, and filamentous fungi, 41%). The inactivation studies on the raspberries mesophilic population indicated a one log reduction of microbial load (95% inactivation efficiency for 1.5 kGy), in the surviving population mainly constituted by filamentous fungi (79-98%). The total phenolic content of raspberries indicated an increase with radiation doses and a decrease with storage time. The same trend was found for raspberries' antioxidant capacity with storage time. Regarding raspberries physicochemical properties, irradiation induced a significant decrease in firmness compared with nonirradiated fruit. However, nonirradiated and irradiated fruit presented similar physicochemical and sensory properties during storage time. Further studies are needed to elucidate the benefits of irradiation as a raspberries treatment process.

Effect of ionizing radiation on antioxidant compounds present in cork wastewater

A preliminary study of the gamma radiation effects on the antioxidant compounds present in cork cooking water was carried out. Radiation studies were performed using radiation between 20 and 50 kGy at 0.4 and 2.4 kGy h(-1). The radiation effects on organic matter content were evaluated by chemical oxygen demand. The antioxidant activity was measured by ferric reducing power assay. The total phenolic content was studied using the Folin-Ciocalteau method. Results show that gamma radiation increases both the amount of phenolic compounds and antioxidant capacity of cork cooking water. These results highlight the potential of this technology for increasing the added value of cork waters.

Avaliação do Projecto Integrado para a Prevenção do Abuso Sexual (PIPAS): Estudo preliminar

Neste artigo apresenta-se um programa de prevenção do abuso sexual implementado na Casa Pia de Lisboa e respectiva avaliação e discutem-se, ainda, critérios para a avaliação de programas. No estudo de avaliação utilizou-se um design longitudinal quantitativo, por questionário, com dois momentos, pré e pós-teste, com seis meses de intervalo entre si. Os participantes (N = 188), do 3º ao 6º ano, foram distribuídos aleatoriamente por grupos controlo e experimental, respondendo a um conjunto de questionários considerados adequados para a avaliação das principais competências treinadas no programa. Os grupos não se mostraram diferentes entre o início e o final da intervenção, mas o papel do colégio e o maior número de sessões contribuíram significativamente para o aumento das competências sócio-emocionais dos jovens. Por fim, discutem-se aspectos da aplicação do programa essenciais para a compreensão dos resultados encontrados e fazem-se recomendações sobre práticas de implementação do programa que optimizem a sua eficácia.

Radiolytic degradation of gallic acid and its derivatives in aqueous solution

Polyphenols, like gallic acid (GA) released in the environment in larger amount, by inducing some unwanted oxidations, may constitute environmental hazard: their concentration in wastewater should be controlled. Radiolytic degradation of GA was investigated by pulse radiolysis and final product techniques in dilute aqueous solution. Subsidiary measurements were made with 3,4,5-trimethoxybenzoic acid (TMBA) and 3,4,5-trihydroxy methylbenzoate (MGA). The hydroxyl radical and hydrogen atom intermediates of water radiolysis react with the solute molecules yielding cyclohexadienyl radicals. The radicals formed in GA and MGA solutions in acid/base catalyzed water elimination decay to phenoxyl radicals. This reaction is not observed in TMBA solution. The hydrated electron intermediate of water decomposition adds to the carbonyl oxygen, the anion thus formed protonates on the ring forming cyclohexadienyl radical or on the carbonyl group forming carbonyl centred radical. The GA intermediates formed during reaction with primary water radicals in presence of oxygen transform to non-aromatic molecules, e.g., to aliphatic carboxylic acids.

Subcapsular hepatic hematoma in an otherwise uncomplicated pregnancy

Subcapsular hepatic hematoma is rare in pregnancies not complicated by pre-eclampsia or the HELLP syndrome. We now report such a case.

Vanadium haloperoxidases from brown algae of the Laminariaceae family

Vanadium haloperoxidases were extracted, purified and characterized from three different species of Laminariaceae--Laminaria saccharina (Linné) Lamouroux, Laminaria hyperborea (Gunner) Foslie and Laminaria ochroleuca de la Pylaie. Two different forms of the vanadium haloperoxidases were purified from L. saccharina and L. hyperborea and one form from L. ochroleuca species. Reconstitution experiments in the presence of several metal ions showed that only vanadium(V) completely restored the enzymes activity. The stability of some enzymes in mixtures of buffer solution and several organic solvents such as acetone, ethanol, methanol and 1-propanol was noteworthy; for instance, after 30 days at least 40% of the initial activity for some isoforms remained in mixtures of 3:1 buffer solution/organic solvent. The enzymes were also moderately thermostable, keeping full activity up to 40 degrees C. Some preliminary steady-state kinetic studies were performed and apparent Michaelis-Menten kinetic parameters were determined for the substrates iodide and hydrogen peroxide. Histochemical studies were also performed in fresh tissue sections from stipe and blade of L. hyperborea and L. saccharina, showing that haloperoxidase activity was concentrated in the external cortex near the cuticle, although some activity was also observed in the inner cortical region.

Purification and characterisation of vanadium haloperoxidases from the brown alga Pelvetia canaliculata

Two enzymes characterised as iodoperoxidases (PcI and PcII), with vanadium-dependent activity, have been purified from the brown alga Pelvetia canaliculata (L.) Decne et Thur. (Fucaceae, Phaeophyceae), collected in the Northern Portuguese coast, at Viana do Castelo. The relative molecular masses were 166 kDa for PcI and 416 kDa for PcII, as determined by gel filtration. SDS-PAGE shows that PcI has just one band corresponding to a subunit of 66 kDa, while PcII shows four bands (66, 72, 157 and 280 kDa). The following kinetic parameters have been determined from a steady-state analysis of the oxidation of iodide by H2O2: PcI, pHopt = 6.0, KM(I-) = 2.1 mM, KM(H2O2) = 110 microM, Ki(I-) = 127 mM; and PcII, pHopt = 6.5, KM(I-) = 2.4 mM, KM(H2O2) = 20 microM and Ki(I-) = 69 mM. These iodoperoxidases are thermostable, as also observed for vanadium bromo- and chloroperoxidases.

[Evaluation of ELISA and counterimmunoelectrophoresis in diagnosis of human neurocysticercosis in Chile]

The aim of this work was to assess the diagnostic accuracy for neurocysticercosis, of ELISA and counterimmunoelectrophoresis techniques, in sera and cerebrospinal fluid. Two hundred eight serum samples (47 coming from patients with confirmed cysticercosis) and 87 cerebrospinal fluid samples (27 coming from patients with confirmed cysticercosis) were analyzed. A crude and standardized extract of swine muscle cysticercus cellulose was used as antigen. ELISA and counter immunoelectrophoresis had a 100% specificity in cerebrospinal fluid. In sera, counterimmunoelectrophoresis had a 94.1% specificity. In sera and cerebrospinal fluid, ELISA had a 85.1% sensitivity. Cross reactions were observed in sera of patients with confirmed hydatidosis. Thus, the high specificity of both techniques in cerebrospinal fluid is probably due to the low incidence of cerebral hydatidosis in Chile. It is concluded that for the diagnosis of neurocysticercosis, antibodies against cysticercus cellulosae must be sought paralelly in serum and cerebrospinal fluid using ELISA and counterimmunoelectrophoresis.

[Prevalence and sociocultural and economic aspects of hypertension in a health center of the northern area of Manaus]

PURPOSE

To verify the prevalence and the possible sociocultural and economic factors involved in high blood pressure (HBP), intending to contribute to the elaboration of public health programs.

METHODS

The blood pressure of 1,766 individuals, aging 13 years old or more, was measured by the auscultatory method, using a stethoscope and a sfigmomanometer. It was included in the HBP group, the individual presenting blood pressure above 140 x 90 mmHg in two measurements on different occasions. These individuals answered a form searching for sociocultural and economic aspects.

RESULTS

Among the individuals examined, 76 were considered to have HBP. There was an increase on the prevalence of HBP with an increase of age, being the greatest among the individuals aging 49 years or more. It was observed significant association between age and HBP (p < 0.05), but the same did not happen with sex or skin color. In most part of the individuals with HBP, it was observed low family income and low educational level. Half of the HBP patients were used to eat with salt and fat.

CONCLUSION

The educational level, economic status, and sociocultural habits of a person constitute factors that must be considered in the development of public health programs for control and reduction of the prevalence of HBP.

Toxoplasma infection after human allogeneic bone marrow transplantation: clinical and serological study of 80 patients

Systematic clinical and serological studies to evaluate the frequency of toxoplasmosis in bone marrow transplant recipients were performed in 80 consecutive patients. Antitoxoplasma antibody titres were measured in donors and recipients before transplant and subsequently post-transplant. Before bone marrow transplant, 54 recipients were seropositive and 26 were seronegative, whereas 35 donors were seropositive and 45 were seronegative. After bone marrow transplant, the frequency of clinical and serological manifestations of toxoplasmosis appeared closely related to the recipient's serological status before transplant. In the seronegative group of patients before transplant the incidence of toxoplasmosis was low: only two patients experienced seroconversion 3 months after bone marrow transplant and one developed clinical symptoms consistent with toxoplasmosis but without cerebral involvement. Clinical toxoplasmosis or secondary elevation of antibody titres was mostly observed in pre-bone marrow transplant seropositive patients; in this group, cerebral toxoplasmosis occurred in four patients and a significant secondary rise of antibody titres was observed in 16 patients. It thus appears that toxoplasmosis is most often related to a reactivation of latent cysts. Prophylactic treatment may be useful in patients presenting serological evidence of past or latent infection before bone marrow transplant.

[Use of acyclovir in the prevention of herpes infections after allogenic bone marrow grafts]

In a double-bind controlled study, oral Acyclovir has been compared to a placebo in a series of 39 consecutive patients undergoing bone marrow transplantation. A dose of 200 mg was given every 6 h from day 8 to day 35 after transplantation. Pharmacokinetic studies have shown the good absorption of the drug despite intestinal damage related to chemoradiotherapy or gut graft-versus-host disease (GVHD), there was no sign of toxicity. The protection against herpes simplex virus (HSV) infection was complete in the treated group when compared to the control group even in patients with high anti-HSV antibody titres. The same protection was observed against cytomegalovirus (CMV) infection. The incidence of HSV and CMV was the same in both groups after treatment ended. This study confirms the efficacy of Acyclovir against HSV infection and possibly against CMV infection when it is given prophylactically after bone marrow transplantation.

Blockade of electrophysiological properties of muscle fibres by lycorine

This study concerns the action of the alkaloid lycorine on electrophysiological properties of single sartorius muscle fibres. Lycorine caused a decrease of the resting membrane potential, a lengthening in the rise and decay times of the action potential and a fall of the muscle accommodation. The depolarizing effect was not affected when Na+ is replaced by choline in the Ringer solution. Lycorine did not inhibit the (Na+ + K+) ATPase activity. The results suggest that action of lycorine on the electrophysiological properties can be attributed to an interference with potassium channels.

Prophylaxis of herpes infections after bone-marrow transplantation by oral acyclovir

In a double-blind controlled study, oral acyclovir was compared with placebo in 39 consecutive patients undergoing bone-marrow transplantation. Acyclovir was given at a dose of 200 mg every 6 h from 8 days before to 35 days after bone-marrow transplantation. Pharmacokinetic studies showed good absorption of the drug, despite intestinal damage related to chemoradiotherapy or gut graft-versus-host disease. There was no sign of toxicity. The protection against herpes simplex virus (HSV) infection was complete in the treated group compared with the placebo group even in patients with high anti-HSV antibody titres before transplantation. The same protection was observed against cytomegalovirus (CMV) infection. The frequencies of HSV and CMV infections were the same in both groups after the cessation of treatment.

Oral acyclovir prophylactic treatment of herpes simplex infection after bone marrow transplantation

In a double-blind controlled study, oral acyclovir has been compared to a placebo in a series of 39 consecutive patients undergoing bone marrow transplantation. A dose of 200 mg was given every 6 h from day 8 to day 35 after transplantation. Pharmacokinetic studies have shown the good absorption of the drug despite intestinal damage related to chemoradiotherapy or gut graft-versus-host disease (GVHD); there was no sign of toxicity. The protection against herpes simplex virus (HSV) infection was complete in the treated group when compared to the control group even in patients with high anti-HSV antibody titres. The same protection was observed against cytomegalovirus (CMV) infection. The incidence of HSV and CMV was the same in both groups after treatment ended. This study confirms the efficacy of acyclovir against HSV infection and possibly against CMV infection when it is given prophylactically after bone marrow transplantation.

Four years experience with dura mater cardiac valves

The clinical use of homologous dura mater cardiac valves was begun in January 1971. Between January 1971 and May 1975, 751 patients received 849 dura mater valves: 428 mitral, 365 aortic, 52 tricuspid and 4 pulmonary. The hospital mortality observed in this series was 13.6% and late mortality was 2.5%. The main causes of death were low-output syndrome in the immediate post-operative period or cardiac failure in the late post-operative period, due to myocardial impairment. Paravalvular leaks and errors in the manufacture of the valve were the main causes of regurgitation both in the immediate and late post-operative period. The incidence of thromboembolism, bacterial and fungal endocarditis was: 0.79%, 0.39%, 0.53% respectively. The results obtained with dura mater valve in a period of four years are satisfactory from the clinical and hemodynamic points of view.