Search PubMed⌕ Search

Biomedical subjects

M Pedro

Publications and source records attributed to M Pedro.

9 recordsLinked to original sources

Catechols from abietic acid synthesis and evaluation as bioactive compounds.

Catechols from abietic acid were prepared by a short and good yielding chemical process and further evaluated for several biological activities namely, antifungal, antitumoral, antimutagenic, antiviral, antiproliferative and inhibition of nitric oxide. Their properties were compared with those of carnosic acid (6), a naturally occurring catechol with an abietane skeleton and known to possess potent antioxidant activity, as well as anticancer and antiviral properties. From all the synthetic catechols tested compound 2 showed the best activities, stronger than carnosic acid.

Abietanes↗

Synthetic secofriedelane and friedelane derivatives as inhibitors of human lymphocyte proliferation and growth of human cancer cell lines in vitro.

Controlled silylation of friedelin (1) from cork smoker wash solids, a byproduct generated during processing of corkboard by steam baking, gave 3-trimethylsiloxyfriedel-2-ene (3) in high yields. Oxidation of 3 with OsO(4)/NMMO produced 2alpha-hydroxyfriedelan-3-one (cerin) (5), from which the new 2,3-secofriedelan-2-al-3-oic acid (6) was obtained quantitatively by periodic acid oxidation. Oxidation of 3 with DDQ afforded friedel-1-en-3-one (8). Reductive ozonolysis of 3 gave 2alpha,3beta-dihydroxyfriedelane, pachysandiol A (7). Compound 6 proved to be a potent inhibitor of human lymphocyte proliferation (IC(50) = 10.7 microM) and of the growth of a human cancer cell line (GI(50) = 5.4-17.2 microM). (13)C NMR data for compounds (3, 4, 5, 6a,7, and 8) are described for the first time.

Antineoplastic Agents, Phytogenic↗

Hepatitis B vaccination in hospital personnel and medical students.

We determined the prevalence of hepatitis B markers and the compliance to hepatitis B vaccination in a University Hospital of Santa Maria, Lisbon. The program was begun in 1989 for all hospital personnel and students of the medical school. The screening included 2,360 health care workers and 1,153 students; 57% (2,360/4,103) of hospital personnel and 41% (1,153/2,779) of medical students appeared for vaccination. The prevalence of hepatitis B markers was 16.8% (397/2,360) for hospital personnel and 5.5% (64/1,153) for students, the chronic carrier appearing in 0.95% (22/2,360) of hospital personnel and 0.3% (4/1.153) of students. The departments with the highest prevalence were the Biochemical Laboratory (64%, 7/11), Surgery (42%, 13/31), Pulmonary (39%, 9/23), Emergency (29%, 7/24), Hematology Laboratory (29%, 7/24), and Orthopedics (29%, 10/35). The prevalence was higher in students in the last 3 years of medical school than those in the first 3 years (12.2% [22/181] vs. 7.2% [8/110], p = NS). Adverse effects to vaccination occurred in 14.5%, with local pain the most frequent in 8.6%. The serologic efficacy was 95% (1,044/ 1,097). A nonresponse was observed in male workers, 13% (26/200) compared with 5% (45/897) for females (p < 0.05). Older employees also showed higher nonresponse: The average age of workers with anti-HBs of 0 IU/l was 52.3 years and those with anti-HBs of more than 100 IU/l was 38.4 years (p < 0.02). Hepatitis B vaccination is safe and effective. Our study shows the need for a more aggressive approach to the vaccination of health care workers because a significant percentage of them are not protected.

Adult↗

[Vaccine against hepatitis B. Eight years of experience].

Hepatitis B virus infection is one of the world's major health problems and health care workers are especially at risk, leading to the need for a high priority vaccination program. Such a program was begun in 1989 in S. Maria Hospital and included all hospital personnel and students of the Faculty of Medicine. The screening included 2360 health care workers and 1153 students. Fifty-five percent of hospital health care workers and 41% of the students participated in the vaccination program. The overall prevalence of hepatitis B markers was 16.8%, for hospital personnel, the chronic carrier being 0.95%, and for the students, 5.5% and 0.3% respectively. The highest prevalence was observed in the Biochemical Laboratory--64% (7/11), Surgery--42% (13/31), Pneumology--39% (9/23), Emergency Department--29% (7/24), Hematology Laboratory--29% (7/24) and Orthopedics--29% (10/35). The prevalence was also higher in students in the last three years of Medical School compared to those in the first three years, 12.2% vs 7.2%, p = NS. Local pain has been the most frequent complaint in 8.6% of vaccinees. The control with the quantification of anti-HBs in the 7th month has shown a serological efficacy of about 95%. A non-response was observed in male workers, 13% compared to 5% for females, p < 0.05. Older employees also showed higher non-response: the average age of workers with anti-HBs of 0 U/L was 52.3 years, and those with anti-HBs of more than 100 U/L was 38.4 years, p < 0.02. Hepatitis B vaccine is a safe and effective preventative measure that has been widely used for years. Our study shows the need for a more aggressive approach to the vaccination of health care workers because a significant percentage of them in our country are not protected.

Allied Health Personnel↗

Damaging effects of high energy shock waves on cultured Madin Darby canine kidney (MDCK) cells.

Shock wave lithotripsy (ESWL) has become an almost non-invasive standard treatment modality for urolithiasis. Several investigations, however, demonstrated that ESWL is not completely free of side effects. Among others alteration of renal tubular function has been reported. To study the effect of shock waves on tubular cells directly an in-vitro model with cultured Madin Darby Canine Kidney (MDCK) cells was established. Suspensions of MDCK cells (7 groups of 6 containers each) were exposed to 0, 16, 32, 64, 128, 256 shock waves (Dornier HM4, 18 kV). Before and 0, 1, 3, 6, 9, 12, 24 h after ESWL the following parameters were measured in the nutrient medium: lactate dehydroxygenase (LDH), glutamate oxalacetate transaminase (GOT), electrolytes. LDH and GOT increased depending on the number of shock waves indicating a membrane damage of MDCK cells. The MDCK model seems suitable for further studies on the effect of shock waves on renal tubular cells.

Animals↗

[Viral infections in intravenous drug addicts. Clinical and prognostic significance].

A retrospective analysis of 135 drug addicts followed between 1986 to 1987, was done, in order to asses the seroprevalence of hepatitis B virus (HBV), hepatitis Delta virus (HDV), hepatitis C virus (HCV) and Human Immunodeficiency virus (HIV), as also their clinical and prognostic significance. A high prevalence of HBV, HDV and HCV infection was observed in this study: 81%, 64% and 83% respectively; in contrast just one case was positive for HIV. Among the drug addicts the frequency of multiple infections (HBV/HCV 51.6%; HBV/HDV/HCV 18.7%; HBV/HDV 2.2%; HCV/HIV 1.1%) was highest in comparison with isolated (HBV 5.5%; HCV 12.1%) or absent infection (73.6% vs 17.6% vs 8.8% respectively; p less than 0.001). Eleven of 12 (92%) patients with Delta hepatitis and HCV superinfection were seronegative for IgM anti-HD; in contrast the case without HCV superinfection was IgM anti-HD positive. In the former group the Alanine Amino-transferases (ALT) were significantly lower comparatively with those HBV positive patients superinfected by HCV (97 +/- 92 IU/L vs 249 +/- 125 IU/L; p = 0.001), and were not different from drug addicts with isolated HCV infection (62 +/- 49 IU/L). The results of this study indicate, a low prevalence of HIV infection in the Portuguese drug addicts and a high frequency of multiple HBV, HDV and HCV infection in the same period of study. Our observations suggest that HCV may have the capacity to inhibit the replication and pathogenic activity of hepatitis Delta virus.

Adolescent↗

[The risk of seroconversion in surgeons of the hepatitis B, hepatitis C and human immunodeficiency viruses (in a specific surgical population)].

The prevalence of hepatitis B surface antigen (HBs Ag) and antibody to hepatitis C virus (HCV) and human immunodeficiency virus (HIV) was determined in the serum specimens of 288 patients treated surgically in the orthopaedic department of an urban public teaching hospital. The cumulative risk of HBV, HCV and HIV seroconversion for an orthopaedic surgeon during the surgical career span was calculated. We found that 1.4%, 3.1% and 1.7% of patients were seropositive for HBsAg, HCV antibody and HIV antibody, respectively. Seropositivity was neither associated with age nor with trauma, whereas male patients had a greater likelihood of seropositivity. Risk factor assessment did not prove to be discriminating in identifying which patients may pose a potential exposure risk. This study supports the concept of universal infection control precautions for orthopaedic surgeons regardless of the patients' risk factor or serologic status.

Adult↗