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J I Santos-Preciado

Publications and source records attributed to J I Santos-Preciado.

At least 19 recordsLinked to original sources
PubMed2007

Mexican anthropometric percentiles for ages 10-18.

OBJECTIVE: To elaborate Mexican growth charts based on international methodology. DESIGN: Data were obtained from the Mexican National Health Survey. The survey was stratified and probabilistic representative of all the country. SETTING: Nationwide open population living in urban and rural areas. SUBJECTS: Boys (8545) and girls (9983) from 10 to 18 years participating in the survey. METHODS: Age, weight and height were recorded. Empirical percentiles were calculated and smoothed. Smoothed curves were approximated using least-mean square estimation. RESULTS: Tables and figures for percentile values of weight, height and body mass index (BMI) for age, as well as percentile values of weight and BMI for height for both genders are presented. Regarding 50th BMI for age percentiles, Mexicans had higher levels than the Americans in the Centers for Disease Control and Prevention growth charts; Mexicans were lower but had similar weights than the Americans. Owing to the high BMI, the percentile corresponding to an overweight level (25 kg/m(2)) at 18 years was 74.5 in boys and 72.5 in girls, whereas obesity level (30 kg/m(2)) at 18 years was 97.3 and 97.4 in boys and girls, respectively. CONCLUSIONS: The present growth charts are snapshots of a Mexican population. Because of the high median BMI compared to US and World Health Organization standards, we must be cautious in establishing an upper normal cutoff for clinical normality, not merely selecting the 85th and 95th percentiles as equivalents of overweight and obesity, respectively. Therefore, we proposed percentiles 74.5 in boys and 72.5 in girls as the action points of overweight as they are the percentiles corresponding to BMI 25 kg/m(2) at 18 years. SPONSORSHIP: The survey was supported by the Mexican Minister of Health. Statistical analyses were sponsored by Dr Del-Rio-Navarro.

Adolescent↗
PubMed2000

Molecular epidemiology of Entamoeba spp.: evidence of a bottleneck (Demographic sweep) and transcontinental spread of diploid parasites.

Entamoeba histolytica causes amebic colitis and liver abscess in developing countries such as Mexico and India. Entamoeba dispar is morphologically identical but is not associated with disease. Here we determined the ploidy of E. histolytica and developed PCR-based methods for distinguishing field isolates of E. histolytica or E. dispar. Fluorescence in situ hybridization showed that E. histolytica trophozoites are diploid for five "single-copy" probes tested. Intergenic sequences between superoxide dismutase and actin 3 genes of clinical isolates of E. histolytica from the New and Old Worlds were identical, as were those of E. dispar. These results suggest a bottleneck or demographic sweep in entamoebae which infect humans. In contrast, E. histolytica and E. dispar genes encoding repeat antigens on the surface of trophozoites (Ser-rich protein) or encysting parasites (chitinase) were highly polymorphic. chitinase alleles suggested that the early axenized strains of E. histolytica, HM-1 from Mexico City, Mexico, and NIH-200 from Calcutta, India, are still present and that similar E. dispar parasites can be identified in both the New and Old Worlds. Ser-rich protein alleles, which suggested the presence of the HM-1 strain in Mexico City, included some E. histolytica genes that predicted Ser-rich proteins with very few repeats. These results, which suggest diversifying selection at chitinase and Ser-rich protein loci, demonstrate the usefulness of these alleles for distinguishing clinical isolates of E. histolytica and E. dispar.

Actins↗
PubMed1998

Onchocerciasis: changes in transmission in Mexico.

There are now three endemic foci of onchocerciasis in Mexico, all located in mountainous areas in the south-east: two in the state of Chiapas and one in the state of Oaxaca. Together, these three foci cover 16,900 km2 and contain about 286,000 people in 947 localities, most of the localities being small and scattered. The main economic activity in all the foci is coffee farming. Introduction of Mectizan (ivermectin, MSD) into Mexico in 1989 revolutionized control of onchocerciasis in the country and made elimination of the disease a reasonable goal. Concerted efforts between 1989 and 1997, supported by Merck & Co., the River Blindness Foundation and the Onchocerciasis Elimination Programme in the Americas, have led to steady decreases in the incidence of new cases, nodule prevalence and skin-snip positivities. The improvement has been most marked in the Oaxaca focus, where transmission may have been interrupted. As prior to attempts at control, the largest populations at risk are in the Chiapas foci, where logistical problems and migration have combined to limit the success of local control programmes.

Filaricides↗
PubMed1997

[Advances in the molecular diagnosis of infectious and parasitic diseases].

During the last decade molecular diagnostic techniques have moved from the research laboratory into the clinical microbiology laboratory. The application of molecular biology for the diagnosis of infections and parasitic diseases by the detection of nucleic acids has steadily grown, and it is very probably that, while they may not displace the traditional diagnostic laboratory, they will be common place in the not to distant future. A detailed description of the principal molecular diagnostic techniques that are currently being used or that have a potential use for the diagnosis, evaluation of disease progression or response to therapy of selected infectious and parasitic diseases, is presented. Emphasis is placed on the rational use of these techniques in regional reference laboratories or highly specialized hospitals; the importance of selecting and implanting those diagnostic techniques with the highest cost-benefit ratio; and finally, the need to train human resources which are highly qualified in the theory and practice of molecular biology.

Adult↗
PubMed1996

Burden of Mycobacterium tuberculosis in sputum samples can be reliably determined using a quantitative, non-radioactive polymerase chain reaction assay.

OBJECTIVE: To develop a rapid assay for quantitation of Mycobacterium tuberculosis in sputum samples using the competitive polymerase chain reaction (PCR) and a colorimetric microtiter well detection format. DESIGN: The assay relies on the co-amplification of a 419 base pair (bp) pab fragment of M. tuberculosis together with a target template (pab/tet) made by splicing a fragment of tet excised from pbr322 between the 5' and 3' ends of the pab fragment to create a 380 bp hybrid template amplified with the same primers but readily distinguishable using probes specific for either pab or tet. RESULTS: We demonstrate a good correlation between the results obtained using this assay and the results of quantitative culture. CONCLUSION: This assay provides quantitative information regarding M. tuberculosis burden in samples containing between 10(3) and 10(8) colony forming units/milliliter (CFU/ml).

Animals↗
PubMed1993

[The prevalence of antibodies against Giardia lamblia in umbilical cord serum and in maternal peripheral blood].

Using an immunoenzymatic assay (ELISA), 40 serum samples from the peripheral blood of women in labor and serum from the umbilical cord of their offspring were analyzed in order to detect the prevalence of antibodies against Giardia lamblia. The results show that 12.5% of the maternal serum samples and 15.0% of those from the umbilical cord had optical density values comparable to those positive for G. lamblia used in the assay. This suggests that important concentrations of maternal IgG antibodies for the parasite are transferred through the placenta. The role that these antibodies play in the neonatal protection is still to be determined.

Animals↗
PubMed1993

[The usefulness of the polymerase chain reaction (PCR) in research and clinical diagnosis in pediatrics].

Recent advances in molecular biology for the first time make possible the widespread application of this science for the diagnosis and clinical investigation of pediatric disease. One very important discovery has been the development of the polymerase chain reaction. This technique allows for the exponential amplification of specific DNA sequences producing quantities sufficient for the molecular diagnosis of a wide variety of diseases. We review some of the fundamental aspects of this technique as well as some of its most promising applications in the field of pediatrics.

Child↗
PubMed1993

[Candida endocarditis in the first year of life].

Candida is an increasing problem as a causal agent of nosocomial infection in neonates and infants. We report 15 cases of infective endocarditis caused by Candida spp treated at the Hospital Infantil de Mexico between 1980 and 1991. The diagnosis of endocarditis was established by the identification of Candida in at least two blood cultures and echocardiographic assessment. From 110 cases of systemic candidiasis during the eleven years period of study, fifteen patients presented endocarditis (13.6%), all had a central venous catheter. Three had antecedent of congenital heart disease. Candida isolation was obtained an average of 28 days after admission. The major clinical findings were: fever in 13 patients, respiratory distress and cardiac murmurs observed in nine respectively. Thrombocytopenia was present in eight children. The echocardiographic evaluation showed vegetations located in the superior vena cava in six, right atrium in five, tricuspid valve in two, inferior vena cava and right ventricle in one respectively. Three cases were subjected to surgical treatment. Nine patients died for a case fatality rate of 60%. The echocardiographic evaluation practiced in all patients with suspicion of systemic candidiasis is critical for the prognosis. The identification of endocardiac involvement coupled with the opportune administration of antifungal therapy and surgical treatment may improved the survival.

Age Factors↗
PubMed1993

[The impact of Haemophilus influenzae infections on Mexican children].

A review of Haemophilus influenzae (Hi) infections in Mexico over the past 32 years was conducted. The proportion of Hi isolates in relation to positive cultures for distinct diseases was distributed as follows for meningitis (9-69%) and for pneumonia with empyema (6-28%). There was no difference in the proportion of Hi isolation between under developed countries and the United States. In other diseases such as septic arthritis, epiglottitis, acute otitis media, acute maxillary sinusitis and in the nasopharyngeal carrier state, the information was too limited. The incidence of Hib invasive disease has been almost eliminated in some areas of the world related to the use of Hib conjugated vaccine. It is imperative for the practitioner to be aware of the advantages of Hib vaccine in infancy.

Adolescent↗
PubMed1992

[Intravenous immunoglobulin in the treatment of neonatal septicemia].

Thirty-seven neonates with confirmed septicemia through hemoculture were studied. Of them, 18 were treated with antibiotic and the other 19 were given 500 mg/kg of intravenous immunoglobin with a pH of 4.25 (IGIV). The greater part of the neonates in this study were full-term or near full-term. There were no differences in age, gestational age and weight, nor in mortality, the bacterias found and the clinical manifestations which were seen in both groups. Yet, the hospitalary stay was shorter for those in the group treated with IGIV (13.9 +/- 5.7 days) than in the trial group (24.4 +/- 10.3 days); as well as some clinical manifestations like diarrhea and splenomegalia (P < 0.05). The serum of the neonates from the IGIV group showed a greater capacity of opsonization and inhibition of bacterial growth than those in the trial group (P < 0.001), coinciding with an increase of 300 mg/dL in the serum levels of IgG of the group treated with IGIV from the 3rd day of the study and the C4 and B-Properdine factor serum levels from the 7th day of the study, while in the trial group, there were no changes in these factors (P < 0.001). Even though no differences were seen in the mortality rate due to septicemia, the results suggest a much shorter evolution of the illness in patients treated with IGIV. In addition, the serum of those patients treated with IGIV showed in in vitro studies, a better bacteriostatic activity and a better capacity to opsonize the bacterias isolated in the hemocultures.(ABSTRACT TRUNCATED AT 250 WORDS)

Bacteremia↗
PubMed1992

[Overview of HIV infections in pediatric population].

A general overview of HIV infection/AIDS in the pediatric population, in Mexico, is provided. The principal categories of transmission in our country are: 45.5% perinatal, 44.0% following transfusion for hemophilia or for other reasons, and less frequently sexual transmission. In the United States and Europe, similar patterns are seen with perinatal transmission being the most important route, at higher percentages than ours. The number of cases of HIV infection in children continues to grow worldwide, primarily reflecting the problem in the adult population.

Child↗
PubMed1992

[Neurologic manifestations in pediatric patients with AIDS].

Since the first cases of childhood AIDS were reported, the neurological involvement has been more frequently recognized. Several motor, intellectual and conductual changes as well as unexplained abnormalities have been described due to CNS infections. Findings have shown HIV to affect the CNS although it is unknown as to when the viral invasion actually occurs. This report describes the neurological manifestations found in pediatric patients with HIV infection at the Hospital Infantil de Mexico and their correlations with CT scans, EEGs, auditory evoked potentials, I.Q.s and postmortem findings. The medical records of 60 symptomatic HIV infected children, stages P0 to P2, are reviewed. Neurological abnormalities were found in 51 patients, 20 of which (39.2%) were due to perinatal infection with symptoms starting, on the average at 11 months 7 days (from the initial contact) taking into consideration in utero exposure. Nine cases (17.6%) were patients infected through transfusions with symptoms appearing on the average at 24 months 8 days; 2 cases (3.9%) were of unknown origin. The CT scans, EEGs and psychometric evaluations of the HIV infected patients correlated well with the clinical findings.

Acquired Immunodeficiency Syndrome↗
PubMed1992

[Bacterial infections in children with AIDS].

The importance of bacterial infections in children with AIDS was emphasized when they were included within the CDC classification system for children under 13 years of age infected with the HIV. The information available in Mexico on frequency, types of infections and causative agents is scarce. In this study, the frequency and microbiology of bacterial infections in children with AIDS seen at the Hospital Infantil de Mexico Federico Gomez is reported. From September 1985 to December 1991, we found 72 HIV infected children, 6 were classified P0, 6 as asymptomatic (P1) and 60 as symptomatic infections (P2). From this last group, 50 were secondarily infected with bacteria; there was a total of 129 episodes of bacterial infections, averaging 2.5 episodes per patient. Respiratory infections were the most frequent (74.41%), followed by septicemia (10.07%), skin and underlying tissue infections (6.96%) and urinary tract infections (6.17%). Infections of the CNS and deep abscesses were less frequent. Overall mortality rate was 76%, however only in 18 children (36%) was it directly attributed to the bacterial infections. Etiology was documented in 46 episodes (33.65%) of which 30 (65.31%) were gram-negative bacteria and 16 (34.78%) were gram-positive. The best possible methodology must be used for the etiologic diagnosis of bacterial infections in children with AIDS in order to select the most appropriate treatment for severe or recurrent bacterial infections.

Acquired Immunodeficiency Syndrome↗
PubMed1992

[Oral manifestations in HIV positive children].

Oral manifestations of HIV infection in children include oral candidiasis, herpetic stomatitis, oral hairy leukoplakia, parotid gland swelling, and other bacterial, viral and mycotic infections. The frequency and natural history of those disorders are not fully defined. The purpose of this work is to inform the oral findings in 57 HIV infected children studied at the Hospital Infantil de Mexico. All 57 patients presented nonspecific gingivitis; however it was not feasible to associate it with the HIV infection; in 28 oral candidiasis was observed, and in 3 cases herpetic stomatitis was documented. Oral candidiasis was found regardless the patient's sex, age, clinical stage, treatment, and mode of transmission of the HIV infection. It has been considered that oral candidiasis is a good marker of immunodeficiency; however, in our patients this correlation was not observed. Also, other HIV-associated oral manifestations were not observed in these cases. The severity and rapid clinical course presented by our patients, may explain both, the lack of correlation between candidiasis and immunodeficiency as well as the absence of other lesions.

Child↗
PubMed1992

[Coronary arteriopathy associated with cardiomyopathy in an adolescent with AIDS].

The purpose of this paper is to inform the case of a 15 years old male patient who died as a consequence of acquired immunodeficiency syndrome (AIDS) complications. The postmortem examination showed a coronary lesion which, to the best of our knowledge, has not been previously described. This vasculopathy was restricted to the coronary arteries; myocardial changes similar to those described in AIDS-associated dilated cardiomyopathy were also present. The coronariopathy was indistinguishable from that described in the blood vessels of the brain in patients with AIDS-related cerebral arteriopathy. We also reviewed the autopsy material from another 14 children who died of AIDS, an in none of them exhibited similar changes in the coronary arteries. In addition we present the clinical findings and some theoretical considerations regarding the pathogenesis of the lesions.

Acquired Immunodeficiency Syndrome↗
PubMed1992

[Health care worker relationship with HIV infected patients or AIDS patients].

The roll of the health care worker (HCW) providing care to HIV-infected patients or living with AIDS has became an important issue in the course of the epidemic, and has impacted the evolution of these patients. Diverse studies have shown that the acceptance of the HCW to care for these patients is related to the degree of education in regards to the subject. There is a positive correlation between knowledge about universal precautions and mechanisms of transmission with the willingness to care for HIV-infected patients. This review shows several studies that have been developed in order to assess the attitudes among HCW's toward HIV-infected patients and the phenomen HIV/AIDS as public health problem. In addition, political issues are discussed in regards to measure protection to HCW as well as HIV-infected patients.

Acquired Immunodeficiency Syndrome↗
PubMed1992

[Medical facilities for women and children infected with HIV].

The phenomena HIV infection and acquired immunodeficiency syndrome (AIDS) among women and children is an important concern for underdeveloped and developing countries and has became a Public Health problem. The medical facilities required for care of these patients are special and demand a comprehensive approach and multidisciplinary team-work. In this way, the patients would receive adequate care for their needs. This review includes the antecedents of the HIV infection among women and children. Mechanisms of transmission, and the current model of medical care that exists in some developed countries. Finally, a commentary is made in regards to the importance of continuing medical education of the health-term in order to confront the AIDS epidemic.

Acquired Immunodeficiency Syndrome↗