Food allergy in breastfeeding babies. Hidden allergens in human milk.

BACKGORUND: Food allergy is a rare disorder among breastfeeding babies. OBJECTIVE: Our aim was to identify responsible allergens in human milk. METHODS: We studied babies developing allergic symptoms at the time they were breastfeeding. Skin prick tests (SPT) were performed with breast milk and food allergens. Specific IgE was assessed and IgE Immunoblotting experiments with breast milk were carried out to identify food allergens. Clinical evolution was evaluated after a maternal free diet. RESULTS: Five babies had confirmed breast milk allergy. Peanut, white egg and/or cow's milk were demonstrated as the hidden responsible allergens. No baby returned to develop symptoms once mother started a free diet. Three of these babies showed tolerance to other food allergens identified in human milk. CONCLUSION: A maternal free diet should be recommended only if food allergy is confirmed in breastfed babies.

High throughput automated characterization of enamel microstructure using synchrotron tomography and optical flow imaging.

The remarkable damage-tolerance of enamel has been attributed to its hierarchical microstructure and the organized bands of decussated rods. A thorough characterization of the microscale rod evolution within the enamel is needed to elucidate this complex structure. While prior efforts in this area have made use of single particle tracking to track a single rod evolution to various degrees of success, such a process can be both computationally and labor intensive, limited to the evolution path of a single rod, and is therefore prone to error from potentially tracking outliers. Particle image velocimetry (PIV) is a well-established algorithm to derive field information from image sequences for processes that are time-dependent, such as fluid flows and structural deformation. In this work, we demonstrate the use of PIV in extracting the full-field microstructural distribution of rods within the enamel. Enamel samples from a wild African lion were analyzed using high-energy synchrotron X-ray micro-tomography. Results from the PIV analysis provide sufficient full-field information to reconstruct the growth of individual rods that can potentially enable rapid analysis of complex microstructures from high resolution synchrotron datasets. Such information can serve as a template for designing damage-tolerant bioinspired structures for advanced manufacturing. STATEMENT OF SIGNIFICANCE: Thorough characterization and analysis of biological microstructures (viz. dental enamel) allows us to understand the basis of their excellent mechanical properties. Prior efforts have successfully replicated these microstructures via single particle tracking, but the process is computationally and labor intensive. In this work, optical flow imaging algorithms were used to extract full-field microstructural distribution of enamel rods from synchrotron X-ray computed tomography datasets, and a field method was used to reconstruct the growth of individual rods. Such high throughput information allows for the rapid production/prototyping and advanced manufacturing of damage-tolerant bioinspired structures for specific engineering applications. Furthermore, the algorithms used herein are freely available and open source to broaden the availability of the proposed workflow to the general scientific community.

Characterizing the microstructures of mammalian enamel by synchrotron phase contrast microCT.

The enamel of mammalian teeth is a highly mineralized tissue that must endure a lifetime of cyclic contact and is inspiring the development of next-generation engineering materials. Attempts to implement enamel-inspired structures in synthetic materials have had limited success, largely due to the absence of a detailed understanding of its microstructure. The present work used synchrotron phase-contrast microCT imaging to evaluate the three-dimensional microstructure of enamel from four mammals including Lion, Gray Wolf, Snow Leopard, and Black Bear. Quantitative results of image analysis revealed that the decussation pattern of enamel consists of discrete diazone (D) and parazone (P) bands of rods organized with stacking arrangement of D+/P/D-/P in all mammals evaluated; the D+ and D- refer to distinct diazone bands with juxtaposed rod orientations from the reference plane. Furthermore, the rod orientations in the bands can be described in terms of two principal angles, defined here as the pitch and yaw. While the pitch angle increases from the outer enamel to a maximum (up to ≈ 40°) near the dentin enamel junction, minimal spatial variations are observed in yaw across the enamel thickness. There are clear differences in the decussation parameters of enamel across species that are interpreted here with respect to the structural demands placed on their teeth. The rod pitch and band width of enamel are identified as important design parameters and appear to be correlated with the bite force quotient of the four mammals evaluated. STATEMENT OF SIGNIFICANCE: The multi-functionality of tooth enamel requires both hardness and resistance to fracture, properties that are generally mutually exclusive. Ubiquitous to all mammalian teeth, the enamel is expected to have undergone adaptations in microstructure to accommodate the differences in diet, body size and bite force across animals. For the first time, we compare the complex three-dimensional microstructure of enamel from teeth of multiple mammalian species using synchrotron micro-computed tomography. The findings provide new understanding of the "design" of mammalian enamel microstructures, as well as how specific parameters associated with the decussation of rods appear to be engineered to modulate its fracture resistance.

The starch-binding domain as a tool for recombinant protein purification.

Recombinant protein purification with affinity tags is a widely employed technique. One of the most common tags used for protein purification is the histidine tag (Histag). In this work, we use a tandem starch-binding domain (SBDtag) as a tag for protein purification. Four proteins from different sources were fused to the SBDtag, and the resulting fusion proteins were purified by affinity chromatography using the Histag or the SBDtag. The results showed that the SBDtag is superior to the Histag for protein purification. The efficient adsorption of the fusion proteins to raw corn starch was also demonstrated, and two fusions were selected to test purification directly using raw starch from rice, corn, potato, and barley. The two fusion proteins were successfully recovered from crude bacterial extract using raw starch, thus demonstrating that the SBDtag can be used as an efficient affinity tag for recombinant protein purification on an inexpensive matrix.

[Results of a comprehensive workplace program for the prevention and treatment of smoking addiction]. / Resultados de un programa integral de prevención y tratamiento del tabaquismo en el entorno laboral.

OBJECTIVES: To assess a comprehensive smoking prevention and treatment program in an electrical appliances company with 1600 employees. MATERIAL AND METHODS: The program included smoking restrictions with the designation of smoking areas and the offer of smoking cessation treatment for the smokers affected. Study variables were age, sex, nicotine dependence (Fagerström Test), carbon monoxide in expired air, adherence to therapy, and smoking abstinence at 1 week, 1 month, 3 months (end of treatment), and 6 months. Successful smoking abstinence was defined as continuous abstinence from the beginning of treatment. RESULTS: Smoking prevalence was 34.8% and 19.5% of smokers requested treatment (77.4% men and 22.6% women). Mean (SD) age was 41.3 (10.3) years. Mean score of nicotine dependence was 5.3 (2.6) and the mean quantity of carbon monoxide in expired air was 35.6 (23.7) ppm. Adherence to therapy was good in 80% of patients. Rate of abstinence was 57.5% at 6 months, signifying a 4% reduction in prevalence. CONCLUSIONS: Workplace smoking cessation programs reduce prevalence and facilitate the establishment of smoking restrictions at the worksite. Companies are convenient settings for the implementation of programs aimed at smoking prevention and treatment.

Prune-belly syndrome and other anomalies in a stillborn fetus with a ring X chromosome lacking XIST.

Ring X chromosomes that lack the X inactivation center and fail to be inactivated have been implicated as a cause of mental retardation and multiple congenital anomalies. We report on a stillborn fetus with karyotype mos45,X/46,X,r(X) and early urethral obstruction or prune-belly sequence, single umbilical artery, limb deficiency, horseshoe kidney, cardiac hypertrophy, persistent left superior vena cava, and axial skeleton abnormalities. Fluorescent in situ hydridization (FISH) studies confirmed that the ring chromosome is X-derived and demonstrated that it lacks the XIST locus. The findings in this fetus are discussed with regard to the spectrum of phenotypes associated with monosomy X and small ring X chromosomes.

Automated solid-phase extraction for sample preparation followed by high-performance liquid chromatography with diode array and mass spectrometric detection for the analysis of resveratrol derivatives in wine.

A method has been developed for the simultaneous determination of resveratrol in all its forms (free isomers and glycosylates) in wines by high-performance liquid chromatography with diode array and mass spectrometric detection. Prior to injection into the column, preconcentration of the sample by automated solid-phase extraction is carried out. In the detection by UV absorption, quantitation was carried out at 280 and 305 nm, and in detection by mass spectrometry, quantitation was performed in the selected ion monitoring mode at m/z 228 and at m/z 238. A comparative study between both detection systems was carried out.

Antitumor monoclonal antibodies generated by immunization with mucins.

This report describes the development and characterization of monoclonal antibody EG2.3. Although produced from a fusion that used splenocytes from donor mice immune to bovine salivary mucin (BSM), EG2.3 bound selectively to a number of human tumor cell lines including colon adenocarcinoma LS174T. Therefore, EG2.3 was compared to B72.3, another mucin (TAG-72) binding monoclonal antibody that also binds to LS174T. Like B72.3, EG2.3 reacted with an epitope on TAG-72. However, these two MAbs differed in a number of ways. Treatment of mucin or TAG-72 with periodate did not reduce the binding of EG2.3 to either antigen. In contrast, B72.3 did not react with either periodate treated antigens. Removal of sialic acid from either BSM or TAG-72 compromised the reactivity of both EG2.3 and B72.3. It was concluded that the EG2.3 binding site was distinct from the carbohydrate structure detected by B72.3.

[Evaluation of the influence of medical education on the smoking attitudes of future doctors]. / Evaluación de la influencia que ejerce la facultad de medicina en los futuros médicos respecto al tabaquismo.

OBJECTIVE: To evaluate whether medical education influences the prevalence, awareness of, and attitudes to smoking of medical students in the first 3 years of their degree. MATERIAL AND METHODS: In this descriptive longitudinal questionnaire-based study of university students, data for medical and veterinary students in their first 3 years were compared. RESULTS: Of the 226 registered first-year medical students, 181 (80%) returned the questionnaire. Of the 180 first-year veterinary students, 161 (89%) replied to the questionnaire. In the third year, 151 questionnaires from medical students and 139 from veterinary students were returned. There were no differences in age or sex between the 2 groups, and both had more women. The prevalence of smokers increased between the first year and the beginning of the third (from 20% to 31% among medical students and from 28% to 32% among veterinary students). An improvement in the awareness of smoking as a risk factor was observed for medical students, but no change in attitude was observed. CONCLUSIONS: The influence of medical education on this health concern is limited as there is no reduction in the prevalence of smoking. Medical education also seems unable to change attitudes to smoking. More students relate smoking to risk factors for certain diseases, showing greater awareness of the health problems caused by smoking.

[Profile of smokers who seek treatment at a smoking cessation clinic]. / Perfil de los fumadores que solicitan tratamiento en una unidad de tabaquismo.

OBJECTIVES: The variety of smoking cessation therapies that have proven effective ranges from simple counseling to intensive interventions. The objective of our study was to identify the characteristics of smokers who currently seek treatment at a smoking cessation clinic. METHODS: Descriptive observational study. The target population consisted of smokers who sought treatment at a smoking cessation clinic. The following variables were studied: sex; age; referral source; marital status; educational level; age at which smoking began, age at which it became a regular habit and the time elapsed between the two moments; level of nicotine dependence (Fagerström Test for Nicotine Dependence); number of cigarettes per day; number of years smoking; use of other potentially-addictive substances (alcohol, caffeine, psychotropic medications and other drugs); presence of concomitant disease; previous attempts to quit smoking; current reasons for smoking cessation; and concentration of expired air carbon monoxide (CO). An initial medical history was taken from each smoker on the waiting list for treatment at the clinic in order to gather data on the study variables; these individuals were then enrolled in a 3-month group smoking cessation program that utilized both medication and cognitive-behavioral therapy. The results are presented in percentages and means with standard deviations (SD) and 95% confidence intervals (CI). RESULTS: 385 smokers were studied--239 (62%) men and 146 (38%) women--the average age being 43.05 years (SD: 9.07). Mean nicotine-dependence (Fagerström Test score) was 6.05 (SD: 2.19); mean number of cigarettes per day: 25.9 (SD: 12.11); mean number of years as a smoker: 25.3 (SD: 9.04); and mean expired air CO: 39.30 (SD: 25.18). Associated disease was present as chronic bronchitis for 27.5% and cardiovascular risk factors for 15%. Previous attempts to quit smoking were reported by 72%; the reasons for the present attempt to quit smoking were the prevention of disease (38%), awareness of dependence (20%) and parental desire to serve as a positive role model for children (10%). CONCLUSIONS: At present, the smokers who attend a smoking cessation clinic are young, severely-dependent adults in the initial stage of preparing to quit. The prevalence of symptoms in this population is low. The profile of the population seeking specialized smoking cessation treatment is expected to change in the future as those with smoking-related diseases and other specific populations of smokers become included.

[Reliability of a questionnaire on smoking to evaluate prevalence, knowledge and attitudes of medical students]. / Estudio de fiabilidad de una encuesta utilizada para valorar la prevalencia, los conocimientos y las actitudes sobre el tabaquismo en estudiantes de medicina.

OBJECTIVE: To evaluate the reliability and reproducibility of results obtained from a questionnaire on the smoking habits of medical students. METHOD: A questionnaire with 30 variables was designed to measure three main parameters: prevalence, knowledge and attitudes toward smoking. First-year medical students at the University of Zaragoza (1997-98 academic year) were asked to fill in the questionnaire, and a code was assigned to each individual respondent. A test-retest method was then used to assess reliability: the same questionnaire was answered by the subjects after a period of time had elapsed. The Kappa coefficient was calculated to measure agreement. RESULTS: The questionnaire was filled in by 181 students at registration and 7 weeks later by 43 students. The first- and second-time questionnaires for 35 individuals were matched by codes. Reliability was good for most variables related to the main characteristics of smoking (such as prevalence, number of cigarettes smoked daily and consonance-dissonance). Reliability was acceptable for most variables related to knowledge but was low for 3 items. Reliability was acceptable for half the items related to attitudes and low for half. CONCLUSIONS: The questionnaire has a generally good level of reliability, with regard to reproducibility, or the likelihood that an individual will respond to an item in the same way at two different times. Some variables that measure attitudes toward smoking, however, are less reliable. Results obtained for those items should therefore be interpreted cautiously.

[Smoking habits among sixth-year medical students in Spain]. / Consumo de tabaco en estudiantes de sexto curso de medicina de España.

OBJECTIVE: To describe and analyze the smoking habits of sixth-year Spanish medical students. MATERIAL AND METHODS: The target population of this descriptive cross-sectional study was students completing their sixth year in Spanish medical schools. An anonymous, self-administered questionnaire was sent to the students' homes by ordinary mail. The relationships between the variables were analyzed using contingency tables, the chi2 test, the Student t test, and analysis of variance with a significance level of P< .05. The software package was SPSS. RESULTS: A total of 3840 questionnaires were distributed to students, and 1340 were returned completed (34.9%). Of the respondents, 27% were smokers (8.7% smoked only on weekends, and 18.3% were daily smokers). The mean (SD) number of cigarettes smoked per day was 10.54 (7.89). Consumption was significantly higher among men than among women. The mean age of initiation was 17.20 years. Of the students who were smokers, 32.54% stated that they had started smoking during their medical studies. The percentage of smokers who stated that they wanted to quit was 76.3%, and 56.6% said that they had already made at least one quit attempt. CONCLUSIONS: It is cause for concern that a large number of students start smoking after they enter medical school. One of the reasons for this is the lack of concern about smoking as a health problem within medical schools. The smoking habits of medical students are affected by the same phenomena that affect those of the general public, such as the increase in the number of women smokers, the influence of sociocultural factors, and the increasingly broader age range of initiation. The lower prevalence of smoking among medical students with respect to other populations is probably due to the fact that, in general, these students have better health habits than the general public, and/or the reasons that led them to study medicine also make them disinclined to smoke.

[Evaluation of a workplace anti-smoking program at a company with 640 employees]. / Evaluación de una intervención sobre tabaquismo en el medio laboral: experiencia en una empresa con 640 empleados.

OBJECTIVES: Awareness of the health risks of passive smoking for non-smokers has led to the development of workplace interventions for smokers, although they are still few in our setting. The objective of this study was to evaluate the efficacy of an anti-smoking program among the workers of a company, in function of changes in the pre- and post-intervention prevalence of smoking in the study population. METHOD: A pre-intervention questionnaire on smoking (prevalence and attitudes) was administered at a company with 640 employees (92% men, 8% women). An anti-smoking program was carried out inside the company during working hours over the next nine months. The questionnaire was then repeated (post-intervention) in order to evaluate its efficacy based on changes. For employees who answered both questionnaires, paired variables were analyzed. RESULTS: The pre-intervention questionnaire was answered by 388 employees (60%), 357 men (92%) and 31 women (8%); their mean age was 48.4 years (SD 9.36). The prevalence of smoking was 55%, including daily smokers, sporadic smokers and others. The mean number of cigarettes per day was 17.86 (SD 2.45). The mean level of nicotine dependence measured by the Fagerström test was 3.3 (SD 2.8) out of 10. The post-intervention questionnaire was answered by 206 employees (32%). Among employees who answered both questionnaires (83), analysis of paired data showed a decrease in the prevalence of smoking of 4% and in the number of cigarettes per day from 17.4 (pre-intervention) to 16.4 (post-intervention). The differences were not statistically significant. CONCLUSIONS: Although the workplace is an appropriate setting for anti-smoking interventions that would contribute to improving the health of smokers, such programs are currently underutilized.

[L-arginine-nitric oxide pathway in hemodialysis]. / Vía de L-arginina-óxido nítrico en la hemodiálisis.

Nitric oxide (NO) is derived from the metabolism of the amino acid L-arginine by NO synthase (NOS). One of the forms of NOS (i-NOS) can be induced by cytokines, bradykinin and endotoxin. During hemodialysis (HD), blood-dialysis membrane interaction can induce production of these mediators. HD can also induce changes of asymmetrical dimethylarginine (ADA), a potent inhibitor of NOS. The aim of this study was to investigate the effect of HD, using cuprophane (C, polyacrilonytrile (PAN) and special polyacrylonitrile (SPAN) membranes, on cellular NOS activity, and changes of plasma tumor necrosis factor (TNF-alpha), bradykinin, ADA and nitrate concentration. Before HD, cellular i-NOS activity was similar with the three membranes. Cuprophane HD induced a significant increase in i-NOS activity from 31 +/- 10 to 48 +/- 12 fmol-1 10(6) cells (p < 0.05). No changes were found in PAN and SPAN HD. The TNF-alpha values increased significantly during HD with C (56 +/- 6 vs 47 +/- 5 pg/ml, p < 0.05). No changes of bradykinin concentration were found during HD. A significant decrease of ADA and nitrate levels was observed during HD with three membranes. No significant correlation was found between percentage increase in i-NOS activity and the changes in other parameters. These findings suggest that HD with bioincompatible membranes can induce activation of cellular i-NOS.

Electroencephalography in congenital malformations of the central nervous system.

We studied clinical and EEG features of 36 cases with congenital malformations of the CNS. Patients were followed at the outpatient clinic of Hospital Cayetano Heredia and of Hogar Clinica San Juan de Dios in Lima-Peru, from January 1984 to June 1992. Eighty percent of the patients had convulsive syndromes and mental retardation. The most frequent malformation was agenesis of corpus callosum, and it was not possible to find a "typical" EEG pattern. The second were porencephalic cysts, with a good clinical-EEG correlation. There were two typical cases of schizencephaly, one of hemimegalencephaly with good prognosis, and one of holoprosencephaly. The results are compared to those obtained for a series we previously reported. Data discussed take into account reports on the subject registered in the literature. It is concluded that EEG is an useful method to evaluate possible CNS malformations in developing countries.

[Cerebral hydatid cyst in children in the Hospital Nacional Cayetano Heredia: apropos of a case]. / Quiste hidatídico cerebral en niños en el Hospital Nacional Cayetano Heredia: a propósito de un caso.

Case report of a 12 years old female child who developed in the last seven months focal neurological signs and progressive intracranial hypertension. CT scan showed a giant cystic tumor, and cerebral hydatidosis has been diagnosed. The hydatic cyst was surgically removed without complications. Cerebral hydatidosis is rare, its diagnosis is clinical and tomographic, and the treatment is always surgical.

[Neurological involvement in free living amebiasis]. / Compromiso neurológico en amibiasis de vida libre.

INTRODUCTION: Free-living amoeba infection is today a known and outgrowth disease, which is suspected when exists a special skin lesion. DEVELOPMENT: Balamuthia mandrillaris is one of these amoebas recently categorized and identified as a cause of meningoecephalitis granulomatous and chronic. Human infection: until 1997 in Cayetano Heredia Hospital (Lima, Peru) was described 24 cases of Balamuthia mandrillaris infection, 10 under 15 years old. All had skin lesion and all died, 16 had conscious impairment, 8 intracranial hypertension and 8 seizures. CONCLUSIONS: The free-living amoebas disease is now an outgrowth illness that depends on its worldwide distribution and association with immunocompromised host. The Balamuthia mandrillaris infection is a new form responsible for a fatal disease and clinical suspected is possible by the occurrence of skin lesion. Is very important to promove in Latin America collaborative studies in order to future actions.