PubMed Health⌕ Search

Biomedical subjects

M F Almeida

Publications and source records attributed to M F Almeida.

16 recordsLinked to original sources

Evaluation of cytokines concentration and percentage of survival of rabies virus-infected mice submitted to anti-rabies Vero-cell propagated vaccine and P. acnes.

Previously, survival of rabies infection was shown to correlate with low IL-6 serum concentration in mice subjected to post-exposure treatment with the Fuenzalida Palacios rabies vaccine in conjunction with the immunomodulator Propionibacterium acnes, previously Corynebacterium parvum. Considering the substitution of the Fuenzalida Palacios rabies vaccine by the Vero cell raised anti-rabies vaccine in almost all countries, the objective of this work was to evaluate the survival and cytokine serum concentration of rabies virus-infected mice treated with P. acnes in conjunction with or the anti-rabies-VERO vaccine. For this, Swiss mice were experimentally infected with street rabies virus and subjected to vaccine and/or P. acnes following infection. Animals were killed at different times and serum was collected to evaluate cytokines. The greatest survival was observed in animals given one or two does of P. acnes in the absence of vaccination. Animals given anti-rabies VERO vaccine alone or with three doses of P. acnes had the second highest survival rate. The group that had the highest percentage of mortality also had the highest IL-6 concentration on the 10th day, a time correlating with clinical symptoms of the animals. The results reinforce the inefficacy of anti-rabies vaccine in only one dose as a post-exposure treatment irrespective of the type of vaccine used, the immunomodulation activity of P. acnes in rabies post-exposure treatment and suggest a role for IL-6 in rabies virus pathogenesis.

Animals↗

Experimental rabies infection in haematophagous bats Desmodus rotundus.

In order to determine the susceptibility and serum neutralizing antibody response of Desmodus rotundus to rabies virus, bats were inoculated with a virus isolated from a naturally infected haematophagous bat. Bats were divided into four groups of 10 animals each. Dilutions of rabies virus containing 100, 1000, 10,000 and 100,000 MICLD50 (lethal dose 50% for mice inoculated by the intracerebral route) were administrated in the pectoral muscle. The presence of rabies virus was detected in brain and salivary glands by fluorescent antibody, mouse inoculation and RT-PCR. The observed mortality for each virus dose was 0, 20, 20 and 60% respectively. Serum neutralizing antibodies were tested for by the rapid fluorescent focus inhibition test, and antibody titres greater than 0.5 IU/ml were found in 53% of bats 30 days after virus inoculation. Resistance to infection was seen in bats that developed low or no detectable antibody response as well as in bats with high titres. Among the 10 bats that died of rabies, eight showed signs of paralytic rabies and two bats showed no clinical signs.

Animals↗

Increased interleukin-10 associated with low IL-6 concentration correlated with greater survival rates in mice infected by rabies virus vaccinated against it and immunomodulated with P. acnes.

Macrophage activity, cytokines serum concentration, serum neutralizing antibodies and lethality by rabies were evaluated in swiss mice experimentally infected with street rabies virus and submitted or not to antirabies vaccination and immunomodulation with P. acnes. Animals were killed at different times and serum was collected in order to evaluate cytokines concentration; peritonial and splenic macrophages were collected for macrophage activity evaluation. Greater survival rates higher IL-10 and low IL-6 serum concentration were observed in vaccinated animals treated using P. acnes.

Animals↗

Direct determination of chlorophenols in landfill leachates by solid-phase micro-extraction-gas chromatography-mass spectrometry.

Landfill leachates represent a serious environmental concern with regard to trace priority pollutants introduced into the aquatic environment. From the analytical point of view, they constitute complex matrices because of their high organic matter content and competition with the trace analytes in the extraction procedure. Although the use of SPME to extract chlorophenols in leachates has already been described in several publications, the limited number of chlorophenols restricts this analysis field of application. This paper presents a new analytical methodology to determine 13 chlorophenols and phenol by SPME-GC-MS in landfill leachates. The overall analysis was performed in 90 min and the detection limits range from 0.005 microg/l (pentachlorophenol) to 2.5 microg/l (phenol). Reproducibility, expressed by the coefficient of variation of repeated extractions at different concentration levels of the analytes, was on average inferior to 10%. Recovery, evaluated by standard addition to leachates, was 86.2% on average. Pentachlorophenol, 2,3,4,5-tetrachlorophenol and 2,3,4,6-tetrachlorophenol were the sole analytes detected at nanogram level in the landfill leachates analysed.

Chlorophenols↗

Kinetics of chromium removal from spent tanning liquors using acetylene production sludge.

The removal of Cr(III) present in spent leather tanning baths by precipitation with acetylene production sludge (APS) is studied. The hydroxide and carbonate contents in APS were 1.05 and 0.10 g of CaCO3/g of dry sludge, respectively, and the Cr concentration in the tanning bath was 2467 mg/L. The experimental work was carried out at 15, 20, 25, 30, and 35 degrees C using APS samples of different grain size (89, 178, and 356 microm). Percent removals after 180-min reaction time using 356-microm APS particles range from 99.0 to 99.9 as temperature increased from 15 to 35 degrees C. Similar or higher removal rates are obtained when using smaller APS particles. Chromium removal efficiencies using APS as precipitant are comparable with those obtained with NaOH, CaO, or MgO. The Cr conversion X increases with time t and is related to the particle radius and the absolute temperature T by the expression X/1 - X= r0(-0.22) exp(45.45-13401/T)t. The average activation energy for the reaction is 111.4 kJ mol(-1). Despite some deviations observed for the finer particles and the lower temperature (15 degrees C), the model describes adequately the results obtained for all APS particle sizes at 20 degrees C.

Acetylene↗

The GAbAergic and cholinergic systems in the retina are differentially affected by postnatal malnutrition during the suckling period.

Malnutrition by severe protein deprivation induces deleterious consequences in the nervous system particularly in the initial period of development. These deficits can alter several important events during development, such as the expression of neurotransmitters. The induction of nutritional deficiency by using low protein diet, similar to that consumed by low income populations in Brazil, was applied in rats to investigate the effect of malnutrition on cells containing gamma-aminobutyric acid (GABA) and acetylcholine in the retina. GABA immunoreactivity was present in cells in the inner nuclear and ganglion cell layers and in processes in the inner and outer plexiform layers in retinas of control and malnourished animals. At postnatal day 8, there is a decrease (ca. 40%) of the GABAergic neurons in malnourished animals. At P13 and P21 the percentage of these neurons increased and was equivalent to control animals in the adult. Glutamic acid decarboxylase activity did not show significant changes between the two groups along development. Choline acetyltransferase immunoreactivity was localized in amacrine cells in the inner nuclear and ganglion cell layers and their processes in the inner plexiform layer. The percentage of cholinergic cells was always higher in malnourished animals than that observed in the control until postnatal day 30, when the same proportion of cholinergic neurons was found in the retinas of both groups. Choline acetyltransferase activity did not show significant changes between the two groups along development. In conclusion, our results show that despite the extreme somatic and behavioral changes observed the neurotransmitter systems studied were at a certain extent shielded from the insult.

Acetylcholine↗

[Controversies in neonatal resuscitation]

OBJECTIVE: To describe the main controversies surrounding newborn resuscitation procedures. SOURCES: Systematic review of articles from MEDLINE, LILACS and Cochrane Library, and of abstracts published in Pediatric Research, using the keywords resuscitation, asphyxia neonatorum, and newborn infant. SUMMARY OF THE FINDINGS: The effectiveness of hypothermia and ambient air ventilation has been under study. The reduction of barotrauma and volutrauma in the ventilation of preterm infants is still a challenge. The indication of endotracheal intubation in preterm infants based only on their extremely low weight is not a general agreement, except if the use of exogenous surfactant is required. There is still some uncertainty about the ideal dosage of intravenous or endotracheal adrenaline and the need of sodium bicarbonate, mainly in preterm infants. The ethical dilemma includes the decision on whether or not resuscitation should be used in circumstances related to gestational age, birth weight and severe congenital anomalies. CONCLUSIONS: Only the results obtained through animal experiments and randomized controlled clinical trials, with a follow-up of the development of newborn infants submitted to certain resuscitation procedures, will allow changing currently used therapies.

Journal Article↗

Neutralizing antirabies antibodies in urban terrestrial wildlife in Brazil.

The prevalence of rabies neutralizing antibodies (NA) in sera of wild animals from São Paulo City (Brazil) was investigated using the Rapid Fluorescent Focus Inhibition Test between 1994 and 1997. Sera from 547 specimens were examined. Marsupials represented 45% of the sample and primates 37%; carnivores, rodents, deer and edentates represented 6, 6, 3 and 2%, respectively. The overall prevalence of NA was 14%. The prevalence of NA was 18% in primates; whereas in marsupials, carnivores, edentates and rodents it was 13, 9, 8 and 6%, respectively. The stratification according to sex, age, and site of capture of the marsupials and primates showed a small predominance in males versus females and a large predominance of adults versus juveniles. The same relationship was seen in specimens captured near human habitations versus specimens captured in their own habitat. It is evident that there is circulation of rabies virus in wild animals, which are not recommended as pets since they represent a potential risk of exposure to rabies virus for both humans and domestic animals.

Animals↗

Expanded shoulder flap in burn sequela.

The expanded shoulder flap is presented as an alternative for the treatment of cervical retraction secondary to burning. The flap has an axial pattern, mainly based on the transverse cervical artery. The anterior limit of the flap is a line that goes from ear lobule, towards the shoulder, to the deltoid muscle. The incision for inclusion of the tissue expander is made at the shoulder, and on that line, with extension and posterior, lateral and medial detachments broad enough to slightly exceed the expander dimensions, with the valve being placed in infraclavicular position. In the immediate postoperative period, a volume around 15% to 20% of the tissue expander's total capacity was infiltrated, which was followed by weekly infiltrations until the expanded area reached a circumference approximately 2 to 3 times larger than the supposed wound after creating the resection of the retraction. The expanded shoulder flap allows coverage of large extensions, by using a single donor shoulder, as it permits not only release of retraction, but also replacement of associated cervical scars by leaner skin, better adjusted to the region's anatomy. Twelve patients were treated with this method, with good results in all cases, and there being no flap delay. Closing of the donor area happened without any stress, which resulted in scars of good quality.

Adolescent↗

Rabies seroprevalence of street dogs from São Paulo City, Brazil.

A sample of 602 street dogs captured by the São Paulo zoonosis-control municipal service was analyzed for the presence of serum antibodies against the rabies virus and compared to a control sample of 37 dogs from the kennel of the police of São Paulo. Data were stratified into 4 age intervals and the age from the street-dog sample was estimated by general aspects and dental observation according to standard techniques. We assumed that seropositivity was due to previous vaccination (no sub-clinical infection). From the prevalence data, we estimated the age-dependent incidence-density rate of vaccination by a simple mathematical model, which also allowed the estimation of the period of antibody protection given by the supposed vaccination. Crude seroprevalence in the street-dog sample was 16.5% and in the sample from the police-kennel dogs was 80%. The average age of first vaccination calculated for the street-dog sample was 5 years of age (if we assumed an average period of vaccine protection of 3 years) - but 5 months of age for the police-kennel sample.

Age Factors↗

[Humoral immune response of dogs to the inactivated suckling mouse brain vaccine used in anti-rabies campaigns in Brazil].

INTRODUCTION: An anti-rabies campaign is undertaken annually in Brazil with of the Fuenzalida & Palacios vaccine. The humoral immune response of dogs vaccinated during the campaigns was researched with the objective of evaluating whether the dogs presented a protective titer (0.5 UI/ml) 12 months after vaccination and how many of these achieved this titer 30 days after a buttressing vaccination. MATERIAL AND METHOD: Three hundred and forty-one specimens of serum of dogs domicilied, 259 in the S. Paulo and 82 in the Paulinia counties, were analyzed utilizing the Rapid Fluorescence Focus Inhibition Test. The immune response was evaluated taking into consideration the nutritional state of the animal and the number of previous vaccinations. RESULTS: The larger number of the dogs had not achieved the 0.5 UI/ml titer after 12 months, independently of the nutritional state and the response to the buttressing vaccination was more apparent in dogs with two or more previous vaccinations. DISCUSSION: The cut off of 0.5 UI/ml as protective titer in dogs and the influence of the nutritional state and health conditions of the animals as responsible for humoral immune response are discussed.

Animals↗

[Isolation of rabies virus from the insectivorous bat Myotis nigricans].

The following is a case study of the natural infection by the rabies virus of an insectiverous bat belonging to the species Myotis nigricans in the municipality of Ribeirão Pires, Greater S. Paulo. Diagnosis was made by means of immunofluorescence and intracerebral innoculation of mice with nervous and intrascapular muscular tissues.

Animals↗

[Laboratory diagnosis of rabies in chiroptera carried out in a metropolitan area of southeastern region Brazil].

Between January, 1988 and December, 1992 the S. Paulo Animal Disease Control Center subjected 289 bats to rabies examinations, utilizing the direct immunofluorescence and biological techniques. Two insectiverous bats belonging to the species Nyctinomops macrotis, representing 0.69% of the total sample, tested positive. Both animals had been captured alive in residential neighborhoods of the city, one in 1988 in the living room of a 7th floor apartment and the other in 1990 on top of a wall surrounding a private house. In the biological tests, the disease showed incubation periods of 13 and 11 days respectively. Although the existence of infected insectiverous bats in urban areas is cause for concern, indiscriminate predatory action against such species can in no way be justified-particularly bearing in mind their importance in preserving the ecological balance of the insect population so prevalent in cities.

Animals↗

Electrophoretic study of the genome of human rotavirus from Maceió, Brazil.

Rotaviruses were detected by enzyme immunoassay (EIA) in 53 (13.3%) of 397 fecal samples from children with acute gastroenteritis in the city of Maceió, Alagoas, Brazil. Polyacrylamide gel electrophoretic (PAGE) patterns characteristic of rotavirus double-stranded RNA were detected in 51 (96.2%) of the 53 EIA-positive samples. Of the RNA-positive samples, 1 (2%) was classified as subgroup 1 (short profile), 49 (96%) as subgroup 2 (long profile) and 1 (2%) could not be classified because of the absence of bands 10 and 11. The strains of subgroup 2 showed a great degree of electrophoretic heterogeneity and could be divided into several subcategories. Two samples showed splitting of one of the genome segments. PAGE, a very sensitive method capable of identifying rotavirus RNA genomes, has demonstrated that human rotaviruses detected in Maceió present many differences in RNA electrophoretic patterns.

Acute Disease↗

Preoperative normovolemic hemodilution in aesthetic plastic surgery.

Normovolemic autotransfusion was used with 11 healthy females who were about to undergo multiple aesthetic plastic surgeries. After collecting a unit of blood immediately prior to surgery, a quick infusion of isotonic saline solution is made, at a 4-to-1 ratio, until reaching a hematocrit equal to or lower than 30%, thus inducing olighemia. The intended consequence is that blood lost during surgery be poor in red cell mass, which means reduced blood loss, leading to improved tissue oxygenation and decreased risk of thromboembolism. The blood thus collected is reinstilled at the end of the intervention. Results indicate that the technique can be prescribed and bring benefits to any patient entering surgery for which the surgeon anticipates heavy blood loss. The method proposed herein is presented as an alternative to homologous and autologous programmed transfusions and as equivalent to these in terms of volume replenishment.

Adult↗

[Positive serology for syphilis in neonatal period: prevalence in secondary level maternity. Association with maternal risk factors and with positive serology for HIV-1].

To study neonatal Syphilis seropositivity incidence, its association with HIV-1 seropositivity and the impact of Congenital Syphilis CDC case definition, cord blood VDRL and Indirect Hemagglutination (IHA) for Syphilis were performed in 3,664 newborns from Dec/91-July/92. A positive group was formed by those with positive VDRL and IHA or just positive IHA. The control group consisted of 200 VDRL and IHA negative neonates. Among the 3,664 neonates 5.6% were seropositive for Syphilis. A significant association was noted (p < or = 0.05) between neonatal seropositivity for Syphilis and mothers older than 20 years, single, with sexual promiscuity, drug use, no pre-natal care, multiparity and previous still-births. All positive neonates fitted in the Presumptive Congenital Syphilis CDC definition. In 50 seropositive for Syphilis neonates ELISA for HIV-1 was performed and 6/50 were positive. Congenital Syphilis is of concern, specially in neonates of mothers with risk factors for Syphilis acquisition. HIV-1 should be considered in seropositive for Syphilis neonates. Adoption of Congenital Syphilis new CDC case definition is advised, particularly in countries where prenatal care is deficient.

AIDS Serodiagnosis↗