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Biomedical subjects

A Alves

Publications and source records attributed to A Alves.

At least 19 recordsLinked to original sources
PubMed2006

Pentachlorophenol removal from aqueous matrices by sorption with almond shell residues.

Sorption with activated carbon has been the technique preferred for pentachlorophenol (PCP) removal from contaminated waters, but regeneration needs and high operation costs are supporting a renewed interest in the search for alternative sorbents. Among them, almond shell, an agricultural by-product, provides interesting economical advantages, once shells account for 50% (in mass) of the whole almond. In this work, the capacity of almond shells to remove PCP from waters without previous activation was studied in batch conditions. While PCP analysis was performed solid-phase microextraction (SPME) followed by gas chromatography with electron capture detection (GC-ECD), mercury porosimetry and Fourier transform infrared spectroscopy (FTIR) provided a preliminary physical and chemical characterization of the sorbent. Almond shells were essentially a macroporous material, with an average surface area of 12.9+/-2.8 m2/g. The efficiency of PCP removal was 93+/-14%, in 24 h, with an initial concentration of 100 microg/l PCP and 5 microg PCP/g shell. Isotherm data adjusted better to Freundlich equation, where K(F) and 1/n were 0.075+/-0.081 mg(1-1/n) l(1/n) and 1.882+/-0.289, respectively. Average desorption efficiency was 7%, indicating strong adsorption capacity. Results proved that almond shells may be an excellent low-cost alternative for PCP removal from contaminated waters.

Adsorption↗
PubMed2006

[Long term outcome following 26 surgical ampullectomies].

BACKGROUND: Pancreaticoduodenectomy (PD) is the standard surgical treatment for malignant ampullomas but is still associated with a mortality and morbidity still ranging from 0 to 10% and from 15 to 40%, respectively. Ampullectomy is an alternative to PD for benign ampulloma or, in high-risk patients, for invasive carcinoma. The aim of this study was to report early and long term results of surgical ampullectomy for presumed benign ampullomas. PATIENTS AND METHODS: From 1981 to 2004, 26 patients from two institutions underwent surgical ampullectomy. Of the 26 patients, 8 had familial adenomatous polyposis (FAP). Surgical ampullectomy was indicated on a multisciplinary basis. RESULTS: Final pathological examination revealed 15 adenomas, 4 in situ adenocarcinomas, 2 endocrine tumors, and 5 other benign lesions. There was no postoperative mortality. Specific morbidity was 8% (N=2). Mean follow-up was 86+/-70 months (range: 3-204). Actuarial overall 5-year survival was 92%. There were 4 local recurrences (none in patients with FAP). Four patients died during follow-up (including 3 from initial disease). CONCLUSION: Ampullectomy is a good alternative to PD in case of benign or non-invasive malignant ampullary lesion, including in selected cases of FAP.

Adenocarcinoma↗
PubMed2006

Residues of the fungicide famoxadone in grapes and its fate during wine production.

Famoxadone is a recently applied fungicide to vines that belongs to the oxazolidinedione family. The fate of famoxadone was studied by considering the decay ratio of this fungicide during the maturation of grapes and wine production. The main factors affecting the presence of fungicide residues such as fruit growth, photodegradation, evaporation, thermodegradation and co-distillation were studied with model systems. An experimental field was treated with a commercial product containing famoxadone at the recommended dose. After this application, residues of famoxadone were found in grapes at 0.27 +/- 0.06 mg kg(-1). In this field experiment, the half-life t(1/2) of famoxadone, which is described by pseudo-first-order kinetics (R2 = 0.74), was 18 +/- 6 days, resulting from the photodegradation. The famoxadone residue levels in grapes were below the established maximum residues level for Europe (2 mg kg(-1)), whilst levels in wine, carried out with and without maceration, were below the calculated limit of detection of the method.

Fermentation↗
PubMed2006

Relationship between biogenic amines and free amino Acid contents of wines and musts from Alentejo (Portugal).

The concentration of biogenic amines and free amino acids was studied in 102 Portuguese wines and 18 musts from Alentejo demarcated (D.O.C.) regions. Most wines were commercial, except for 38 monovarietals obtained by micro vinification. Musts from the varieties used to produce the latter wines were also studied. Both biogenic amines and free amino acids were analyzed by HPLC using fluorescence detection for their o-phthalaldehyde/fluorenylmethyl chloroformate (OPA/FMOC) derivatives. The most significant amines (average 10.8 mg/L for histamine+tyramine in red, and 7.4 mg/L for white wines) were found to be present at low levels and, although no important relationship between each individual biogenic amine could be obtained, the total amine content depends significantly on the assimilable amino acid content in wine.

Amino Acids↗
PubMed2006

Non-surgical treatment of peri-implant pathology.

INTRODUCTION: Peri-implant pathologies consist of an inflammatory process affecting the soft and hard tissues surrounding the implants. Chlorhexidine is considered the gold standard antiseptic, with a large variety of choice in administration. In this study, a protocol for the irrigation of peri-implant pockets with a chlorhexidine gel, using a plastic needle for the delivery of the product into the peri-implant pockets is described. STUDY PARTICIPANTS AND METHODS: Nine patients with at least one implant presenting peri-implant pathology (inflamed soft tissue associated with bone loss around the implant) were enrolled in this prospective clinical study, and followed-up for 1 year, where clinical parameters such as modified plaque index, modified bleeding index, probing pocket depths, attachment levels were assessed at baseline, 1 month, and 1 year after implementation of the treatment protocol. RESULTS: Treatment success was achieved in eight of the nine patients (and in 11 of the 13 implants) according to the success criteria adopted by the authors of this study. DISCUSSION: Infection control lies at the heart of peri-implant treatment. The control of three factors such as optimal diagnosis, removal of the aetiological factor of the disease (proper removal of debris and decontamination of the peri-implant sulcus/pocket) and a good patient's oral hygiene self-care represents the key to success, resulting in good treatment outcomes when managing peri-implant pathologies. The protocol used (irrigation of peri-implant pockets with chlorhexidine gel delivered by a plastic needle) is considered to be of utility.

Aged↗
PubMed2006

Primary and secondary tumours occurring simultaneously in the brain of a dog.

Primary brain tumours of a single histological type and metastatic brain tumours are well described in dogs in the current veterinary literature. However, the concurrent presence of a primary and secondary tumour in the brain of a dog has never, to the authors' knowledge, been previously reported. The clinical and pathological features of a nine-year-old, female boxer with an oligodendroglioma and metastases from a mammary gland adenocarcinoma occurring simultaneously in the brain are described in this case report. Information in the veterinary literature on multiple malignancies affecting the central nervous system is very limited; therefore, a discussion about comparative situations in human medicine has been included.

Adenocarcinoma↗
PubMed2005

Sorption behaviour of bifenthrin on cork.

Biphentrin, a known pyrethroid, was studied, aiming its removal from aqueous solutions by granulated cork sorption. Batch experiments, either for equilibrium or for kinetics, with two granulated cork sizes were performed and results were compared with those obtained with of activated carbon sorption. Langmuir and Freundlich adsorption isotherms were obtained both showing high linear correlations. Bifenthrin desorption was evaluated for cork and results varied with the granule size of sorbent. The results obtained in this work indicate that cork wastes may be used as a cheap natural sorbent for bifenthrin or similar compounds removal from wastewaters.

Adsorption↗
PubMed2005

Evolution of ochratoxin A content from must to wine in Port Wine microvinification.

To study the evolution of ochratoxin A (OTA) content from must to wine during the making of Port Wine, grapes from the five most common varieties of Port Wine were harvested and combined in equal percentages in order to perform microvinifications. Three sets of assays were studied: a blank (A), where the most common Port Wine-making process was used; in the second (B), a solution of OTA was added to the initial must; in the third (C), the grapes were aspersed with an inoculating solution of OTA-producing fungi. Samples were collected, in duplicate, on four different occasions throughout the process. The influence of the addition of SO2 to the must was also assessed in each set. The quantification of OTA was based on the standard reference method for wines (European Standard prEN 14133), which includes clean-up via immunoaffinity columns and HPLC with fluorescence detection. The limits of detection were 0.076 microg/l for wine and 0.114 microg/l for must. The method was validated by assessing the precision, accuracy and by obtaining an estimate of the global uncertainty. Overall, the levels of OTA observed during the vinifications dropped by up to 92%, and no grapes used in this work were contaminated naturally.

Chromatography, High Pressure Liquid↗
PubMed2005

[CT-Guided transgluteal approach for percutaneous drainage of pelvic abscesses: results in 21 patients].

OBJECTIVE: Percutaneous drainage of pelvic abscesses may be challenging using a conventional anterior route because of overlying intestinal or vascular structures. Although, the posterior transgluteal route is not commonly performed, it may provide a safer approach when the conventional anterior route is not feasible. We retrospectively analyzed our experience in transgluteal percutaneous drainage of pelvic abscesses in 21 patients to determine the feasibility, safety, tolerance and efficacy of this technique. METHODS: The data of 21 patients with pelvic abscesses (15 postoperative and 6 secondary to diverticulitis) who were treated by CT-guided percutaneous transgluteal drainage between 1992 and 2002 were reviewed. Transgluteal drainage was considered as failure in case of persisting clinical sepsis, recurrence of abscess or when surgery was needed. RESULTS: The procedure was well tolerated in all patients. No major complication was observed. In one patient mild hematoma of the piriform muscle was noticed on postprocedure CT scan but did not require a specific treatment. Successful drainage as documented by follow-up CT examination was observed in 20 patients (20/21; 95%). One case of recurrence which was successfully treated by repeated percutaneous transgluteal drainage was observed in our series. CONCLUSION: Percutaneous imaging-guided transgluteal drainage is a feasible, safe, well-tolerated and effective method for the treatment of pelvic abscess when a conventional anterior route is not feasible.

Abscess↗
PubMed2005

French multicentre prospective observational study of laparoscopic versus open colectomy for sigmoid diverticular disease.

BACKGROUND: The aim of this study was to compare in-hospital morbidity and mortality rates after elective laparoscopic and open colorectal surgery for sigmoid diverticular disease (SDD). METHODS: This prospective national multicentre observational study included all consecutive patients undergoing open or laparoscopic elective colectomy for SDD in a 4-month period between June and September 2002. Postoperative in-hospital mortality and morbidity in the two groups were compared. RESULTS: Three hundred and thirty-two consecutive patients undergoing either laparoscopic (163 patients) or open (169 patients) colectomy for SDD were analysed. Overall postoperative mortality and morbidity rates were 0.3 and 23.8 per cent respectively. The morbidity rate was significantly higher in the open than in the laparoscopic group (P < 0.001), leading to a significantly longer hospital stay (P < 0.001). The morbidity rate remained significantly higher in the open group when the patients were matched for age (P = 0.015) or American Society of Anesthesiologists score (P = 0.028). An open procedure (relative risk (RR) 2.13 (95 per cent confidence interval (c.i.) 1.29 to 3.45)), age over 70 years (RR 1.62 (95 per cent c.i. 1.14 to 2.30)) and intraperitoneal contamination (RR 2.54 (95 per cent c.i. 1.18 to 5.50)) were identified as independent risk factors for morbidity. CONCLUSION: A laparoscopic approach to elective treatment of SDD may be associated with reduced postoperative morbidity and hospital stay. A randomized study is required to confirm these results.

Aged↗
PubMed2005

Factors that predict conversion in 69 consecutive patients undergoing laparoscopic ileocecal resection for Crohn's disease: a prospective study.

PURPOSE: This prospective study was designed to identify factors that could predict conversion in patients undergoing first laparoscopic ileocecal resection for Crohn's disease. METHODS: Between 1998 and 2004, 69 consecutive patients (32 males; mean age, 32 +/- 9 years) who had undergone a first laparoscopic ileocecal resection for Crohn's disease were included in a prospective study. Twenty-one patients (30 percent) were converted into laparotomy. Possible factors for conversion were analyzed by both univariate and multivariate analyses. RESULTS: No patient died. Four patients (9 percent; 2 in each group) required five reoperations because of intraperitoneal hemorrhage (n = 1), anastomotic fistula (n = 3), and small-bowel obstruction (n = 1). Mean hospital stay was significantly increased in converted compared with laparoscopic patients (9 +/- 4 vs. 7 +/- 3 days; P < 0.05). On univariate analysis, more than three episodes of acute flare of Crohn's disease (P = 0.02), male gender (P = 0.03), preoperative immunosuppressive drugs (P = 0.04), intra-abdominal abscess or fistula at the time of laparoscopy (P = 0.02), and resection of other intestinal segment (P = 0.02) were factors that predicted conversion. On multivariate analysis, recurrent medical episodes of Crohn's disease (odds ratio, 2; 95 percent confidence interval, 1-4), and intra-abdominal abscess or fistula at the time of laparoscopy (odds ratio, 15; 95 percent confidence interval, 4-78) were the two independent risk factors for conversion. CONCLUSIONS: This prospective study demonstrated that the severity of the disease increased significantly the conversion rate of the first laparoscopic ileocecal resection. Knowledge of these risk factors for conversion could be helpful in preoperative preparation and counseling of patients.

Abscess↗
PubMed2005

Morphology and phylogeny of Botryosphaeria dothidea causing fruit rot of olives.

The taxonomic position of the causal agent of fruit rot of olives was determined from fresh collections of the fungus from central Greece. In culture it formed two types of conidia, namely fusiform, hyaline, aseptate conidia typical of the genus Fusicoccum, and dark-walled, ovoid, ellipsoid or fusiform, 1-2 septate conidia that are not typically observed in Fusicoccum. A phylogenetic analysis based on ITS and EF1-alpha sequences placed the fungus within the same clade as Fusicoccum aesculi, which is the anamorph of Botryosphaeria dothidea, and the type of the genus Fusicoccum.

Ascomycota↗
PubMed2005

Sorption of pentachlorophenol on pine bark.

The minimization of pentachlorophenol (PCP) transport in the environment driven by industrial wastewater discharges can be accomplished by sorption in natural, available and low cost by-products like pine bark. Taking into account that PCP is a chemical which behaviour is highly dominated by the surrounding features, this work intended to evaluate the sorption kinetics and equilibrium parameters according to the pH and temperature as well as the pine bark particle size. The PCP uptake by pine bark showed to be faster in the initial phase followed by a slower process, being 24 h the suitably time to reach the sorption equilibrium in the range of pH studied. The neutral PCP species showed to have higher binding capacity to pine bark than the anionic PCP, which was reflected in a decrease in the distribution coefficient (Kd) of the linear sorption isotherm with the increase of solution pH from 2 to 7. On the other hand, between 10 degrees C and 35 degrees C, the temperature does not seem to play a significant role in the PCP sorption by pine bark, while the sorbent size is a key parameter to enhance the overall process.

Adsorption↗
PubMed2005

Outbreaks caused by parvovirus B19 in three Portuguese schools.

This paper reports the study of outbreaks of an acute exanthematous disease among children of three schools in the municipality of Braga (Portugal). Laboratory tests were performed for five cases, showing that the disease was not due to infection by measles or rubella virus, and infection with parvovirus B19 was confirmed. There were 41 cases in children: 12 in the kindergarten, 17 in the secondary school and 12 in the primary school. There was only one case in a staff member, who worked in the kindergarten. Eight cases were identified among household contacts; two of them were brothers, one from the kindergarten and another from the secondary school, where the outbreak occurred after the kindergarten outbreak. The estimated values of the basic reproduction number R0 were very low and it is very likely that asymptomatic infectious cases have occurred. The local health authority produced written documents and met with staff members and parents. Primary healthcare facilities and the obstetric department of the local hospital were also informed. As we are approaching the elimination of measles in Portugal and the rest of Europe, with very high vaccine coverage, it is very likely that a high proportion of infectious non-vesicular exanthemas will be due to B19 infections. This is to be taken into account in the design and conduct of surveillance activities, in the context of measles and rubella elimination programmes.

Child↗