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Biomedical subjects

H Schenone

Publications and source records attributed to H Schenone.

At least 217 records · Page 12Linked to original sources
PubMedDate not supplied

[Frequency of intestinal protozoosis in the Mexican Republic].

The reports about the frequency of intestinal protozooses found in humans who live in different localities of the Mexican Republic, are in general uncertain and not trustworthy, possibly because very few and poor epidemiological surveys have been undertaken in the country. However, with the few trustful studies carried out (1981 to 1991), it is possible in Mexico, to verify that amibiasis, giardiasis and criptosporidiosis are present with significant percentages of infection: 30.6, 22.3 and 39.3% respectively. With the summary of the researches analyzed in this article, one can conclude that human infections by intestinal protozoa in the Mexican Republic, at the present time, are almost as frequent as in past decades. This occurs because still remain the factors that contribute to the persistence and spreading of intestinal parasites, such as fecalism, poor hygienic and alimentary habits, within a deficient environmental sanitation.

Adolescent↗
PubMedDate not supplied

[Treatment of pediculosis capitis in children with permethrin 1% shampoo or lotion].

A clinical and entomological trial was carried out in 88 head louse (Pediculus humanus capitis) infested children treated with a single dose of 1% permethrin shampoo or lotion. The sex distribution was 47 males an 41 females with ages ranging between 5 and 14 year olds. In order to assess the efficiency of treatments, search for adult forms, nymphs and eggs (nits) of the parasite was performed in each of the children, before and after treatment (30 minutes, 7 days and 21 days). The entomological evaluations consisted in stereoscopic and microscopic examinations of a mean of 12 hair samples taken from the retroauricular and occipital regions of each of the children, the biological condition of eggs, viable (immature, mature), dead and empty, was recorded. The cure rates--both clinical and entomological--obtained were 91.5% for shampoo and 95.2% for lotion. No adverse reactions with the two formulations used were reported. In conclusion, 1% permethrin shampoo or lotion in an effective and safe treatment for pediculosis capitis.

Administration, Topical↗
PubMedDate not supplied

[2 new cases of ophidism in Chile].

Two cases of ophidism seen at the Emergency Department of the Sotero del Rio Hospital, Santiago, during December 1993, are presented. Two young males were bitten by a chilean snake (Dromicus chamissonis) presenting local acute pain, edema and hemorrhagic reaction. In one case, systemic involvement was diagnosed. The clinical presentation and laboratory results are described. The characteristics and frequency of ophidism are discussed.

Adolescent↗
PubMedDate not supplied

[Epidemiology of trichinosis in Chile. Prevalence study by immunodiagnostic reactions].

In the period 1983-1994 a series of seroepidemiological surveys, by using immunodiagnostic tests for trichinosis, was carried out in 138 localities and health institutions from the 13 regions of the country. Thus, a total of 12,882 randomly selected persons, with different sex and age distribution, were submitted to precipitin test and indirect hemagglutination test for trichinosis. One hundred and ninety one (1.5%) persons resulted positive for trichinosis. Higher rates of infection were observed in central and southern Chile. No differences of positivity, according to age sex, but constant increase parallel to age of the individual were detected. The general prevalence rate of infection of 1.5% is in a reasonable accordance with the prevalence of 2.0% found in human corpses in 1992.

Adolescent↗
PubMedDate not supplied

[Epidemiology of Chagas' disease in Chile. Serological follow-up of 1,906 inhabitants from an endemic rural area, IV Region, 1991-1993].

The IV Region (29 degrees 30'-32 degrees 13' south lat.) is located in the center of the geographical area of distribution of Chagas' disease in Chile. Triatoma infestans is the main and almost exclusive vector of Trypanosoma cruzi in this country. The mean prevalence rate of T. cruzi human infection in urban and periurban sections of IV Region is 24.7%. To assess the impact of anti-T. infestans activities, by means of health education and sprayings of dwellings with insecticides, carried out in the IV Region since 1980, during January-February (summer) a serological follow-up to residents from 46 rural chagasic localities was performed. An indirect hemagglutination test and an indirect immunofluorescence test were done to each of the surveyed persons. In 1991, 303 (15.9%) out of 1,906 examined people resulted serologically positive. In 1992, previous discarding the positive individuals found in 1991, 1,334 persons were examined resulting positive 9 (0.7%). In 1993, 1,398 persons were surveyed and 26 (1.9%) were positive. It is noteworthy that none of these 35 positive persons had been surveyed in 1991, being difficult to assert if any was positive before. Two infants, daughters of positive mothers, serologically positive at the beginning, changed to negative in the following survey, indicating that it was a passive transfer of maternal specific antibodies. According to the results of this study, it is concluded that dwelling spraying with persistent-activity insecticides against T. infestans and health education are good tools in the control of T. cruzi human infection, particularly when the involved community participates.

Adolescent↗
PubMedDate not supplied

[Comparison of the frequency of electrocardiographic changes in groups of apparently healthy persons with a positive serology for Chagas' disease, for toxoplasmosis or for both parasitoses].

In order to compare the frequency of electrocardiographical abnormalities among apparently healthy persons with Trypanosoma cruzi and Toxoplasma gondii infections, electrocardiogram (EKG) and the corresponding indirect hemagglutination tests (IHAT) were performed to 13,444 randomly selected rural and suburban inhabitants from the seven first regions of Chile which are located in the geographic area of distribution of Chagas' disease in the country. The IHAT for each parasitosis resulted positive (titers > or = 1:16) for Chagas' disease alone in 1,289 (9.6%), for toxoplasmosis alone in 3,519 (26.2%) and for the two infections in 994 (7.4%). EKG abnormalities of all type (AAT) and suggestive of a chagasic etiology (ASChE) were found in 18.5 and 8.3% respectively of the T. cruzi infected group, in 10.9 and 3.2% of the T. gondii infected group, in 18.9 and 4.8% of the group simultaneously infected by the two parasites, whereas AAT and ASChE were found in 7.9 and 1.8% of the IHAT negative group. All the corresponding percentage differences between abnormal EKG had a statistical significance (p < 0.05). Besides the increasing of the IHAT positivity, for each infection parallels to the age grouping of the studied persons, a similar situation was observed in the frequence of the AAT and ASChE mainly among people aged > or = 50 years. As T. cruzi and T. gondii infections sometimes isoletely adopt a high virulence and overlap in a proportion higher than 43.0% in Chagas' disease endemic areas, it is advisable to consider these etiologic possibilities in the presence of patients with a myocardiopathy of dubious interpretation, particularly when AIDS is involved.

Adolescent↗
PubMedDate not supplied

[Frequency of electrocardiographic alterations in apparently healthy persons with indirect hemagglutination reaction positive for toxoplasmosis].

An indirect hemagglutination test (IHAT) for toxoplasmosis and electrocardiogram (EKG) were performed to 11,161 apparently healthy inhabitants with negative IHAT for Chagas' disease, from 259 rural and periurban localities sited in the first seven regions of Chile (geographic area of distribution of Chagas' disease in the country). The age of the 11,161 examined people ranged between 5 and 94 years, being 4,518 males and 6,643 females. The IHAT for toxoplasmosis was considered positive with titers > or = 1:16. This test resulted positive in 3,519 (31.1%) persons (30.8% in males and 32.0% in females). Positivity of the IHAT increased from 21.2%, in the youngest group (< 10 years) up to 46.9% in the oldest group (> or = 60 years). Different types of EKG alterations were observed in 10.9% of the IHAT positive individuals and in 7.9% of the IHAT negative ones. In both groups the percentages of altered EKG increased parallel with age. The overall difference of percentages of altered EKG in IHAT positive and IHAT negative persons has a statistical significance with p < 0.001. This study suggest the convenience to consider toxoplasmosis as a cause of chronic myocardiopathy in epidemiological studies on Chagas' disease, because a possible Toxoplasma gondii infection may contribute to overincrease the magnitude of the impact of Trypanosoma cruzi in the generation of the quoted myocardiopathy.

Adolescent↗
PubMedDate not supplied

[Positivity of xenodiagnosis, according to age, in persons with positive serology for Chagas disease].

An analytical study of positive xenodiagnosis (XD), according to age distribution, in people with a positive indirect hemagglutination test (IHAT) for Chagas' disease has been carried out. A total of 1,137 IHAT for Chagas' disease positive persons were submitted to two wooden XD boxes containing 7 Triatoma infestans nymphs III each. The positivity (%) of XD in the different age groups was: 0-9 year-old (60.8), 10-19 (35.8), 20-29 (31.5), 30-39 (28.7), 40-49 (30.0), 50-59 (34.3) and > or = 60 (43.3). The 60.8% positivity of XD in children under 10 years of age is possibly due to the rather recent Trypanosoma cruzi infection in this age group and to diverse immunological mechanisms, which decrease with the age increasing.

Adolescent↗
PubMedDate not supplied

[Presence of Triatoma spinolai in human dwellings].

Triatoma spinolai is a wild species of triatomine existing exclusively in Chile, with scarce epidemiological importance in the transmission of Trypanosoma cruzi to man. It has been found in environments from 3000 meters down to the sea level. Exceptionally it has been found in human dwellings. In order to clarify the possibility of an adaptation of T. spinolai to human dwellings a study was undertaken in 50 rural-periurban dwellings from regions III, IV, V and Metropolitan in which this triatomine was found. The dwellings were classified in houses (35) and huts (15). The insect was trapped in 35 dwellings (24 houses and 11 huts) located in declivities (70%) and 15 dwellings (14 and 1) located in plains. This proportion is significantly higher than the average of 26.2% for dwellings located in declivities. It is concluded that the presence of T. spinolai in dwellings, more than a triatomine invasion is the result of the construction of huts or houses in the insect habitat.

Animals↗
PubMedDate not supplied

[Epidemiology of Chagas disease in Chile. Frequency of human Trypanosoma cruzi infection by age groups and regions].

Chagas' disease is endemic in rural-periurban sections of the northern half of Chile which includes the first seven political-administrative regions of the country (18 degrees 30'-34 degrees 36' South lat.). Data concerning to the results of an indirect hemagglutination test for Chagas' disease performed to 15,418 rural-periurban and 45,119 urban inhabitants fron the chagasic endemic regions are presented. Migrations from rural-periurban to urban areas have contributed to the dissemination of Trypanosoma cruzi infection. General rates of infection for rural-periurban (r-p) and urban (u) sections were 16.7% and 1.9% respectively. The higher prevalence rates were detected in Region III with 27.2% (r-p) and 3.9 (u) and Region IV with 24.7% (r-p) and 3.5% (u), while the lower prevalence rates corresponded to Region VI with 7.0% (r-p) and 0.8% (u). Serological positivity increased parallelly with age in all regions.

Adolescent↗