The impact of nutritive and non-nutritive sweeteners on the central nervous system: preliminary study.

BACKGROUND: Human consumption of food and beverages containing added nutritive or non-nutritive sweeteners has increased worldwide. OBJECTIVE: The present study evaluated the possible impact of frequent sweetener consumption on human CNS activity and functions through neuropsychological testing and EEG/qEEG analysis. METHODS: A sample of 23 women and 16 men, aged 18-35, with a body mass index between 18 and 24.9 kg/m2 was evaluated. Participants underwent a 1-week washout period in which food with added sugars or sweeteners was restricted from their diet. Initial assessment of cognitive functions was performed with a validated neuropsychological test and EEG/qEEG analysis, prior to supplementation. Sucrose, sucralose, or steviol glycosides, in commercially available presentations, were randomly assigned to three experimental groups of 13 participants each. Sweeteners were supplemented in fixed amounts, daily, for six weeks. After supplementation, neurological tests were repeated and the initial and final results were compared. RESULTS: The results show no significant changes between final and initial measures in the steviol glycosides group. However, a significant decrease in encoding memory was found in the sucrose group in the final evaluation. Strikingly, the sucralose group showed a significant decrease in overall memory, encoding memory, and executive functions after supplementation. Furthermore, qEEG analysis showed an increase in theta wave absolute and relative power at the final evaluation in the same group. CONCLUSION: These data show that frequent consumption of specific sweeteners is accompanied by measurable changes in EEG/qEEG activity and neuropsychological test performance in humans.

Clinical and demographic profile of traumatic spinal cord injury: a Mexican hospital-based study.

STUDY DESIGN: Review of clinical data. OBJECTIVES: The objective of this study was to describe the clinical and demographical profile of patients with traumatic spinal cord injury (TSCI) admitted to a single center. SETTING: Unidad de Medicina Física y Rehabilitación Centro, México. PARTICIPANTS: Patients with TSCI attending rehabilitation for the first time. INTERVENTION: Not applicable. MAIN MEASUREMENTS: Age, gender, educational level, occupational activity, causes of injury, level of injury, neurological level, injury severity and category were recorded. RESULTS: Four hundred and sixty-four clinical files of patients with TSCI were collected. The mean age was 37.9 ± 15.9 years; 78.2% (363/464) were male, basic educational level predominated in 63.6% (296/464) and 73.1% (339/464) were employed. A fall was the main mechanism of the injury in 41.6% (193/464), replacing automobile accidents from the first place. The mean age of persons who suffered falls was 44 ± 16 years. Injuries sustained by younger persons were due to violence (28.4 ± 10.1 years) and the cause of injury associated with male gender was violence. Thoracic level was most often affected (in 56.7%, 263/464) and neurological level C4 in 13.4% (62/464). In regard to the extent of the injury, lesions classified as American Spinal Injury Association A predominated (56.2%, 261/464) as with complete paraplegia in 43.3% (201/464). CONCLUSIONS: The mean age of our patients was 37 years. Men are affected in a higher proportion. Our population has <9 years of study. Physical labor was the usual pre-injury activity. The main mechanism of injury was falls. Thoracic spine was the most affected.

Genotoxicity in oral epithelial cells in children caused by nickel in metal crowns.

The micronucleus (MN) assay evaluates the effects of low doses of genotoxic carcinogens and can detect structural lesions that survive mitotic cycles. The objective of this study was to determine both the genotoxicity of nickel (Ni) in buccal epithelial cells and the urinary excretion of Ni in children with metal crowns. This was a prospective longitudinal study based on 37 patients selected at the Facultad de Odontología de la Universidad Autónoma de Coahuila. MN assays were performed using buccal cells from the 37 patients, and Ni levels were determined from urine samples using inductively coupled plasma mass spectrometry at 1 (basal value), 15, and 45 days following the placement of crowns in each patient. Ni urinary excretion levels increased from 2.12 ± 1.23 to 3.86 ± 2.96 mg Ni/g creatinine (P < 0.05) and the frequency of exposed micronuclei increased from 4.67 ± 0.15 to 6.78 ± 0.167/1000 cells (P < 0.05) between 1 and 45 days post-crown placement. These results suggest that odontological exposure to metal crowns results in genotoxic damage at the cellular level of the oral mucosa and an increase in the urinary excretion of Ni within 45 days of exposure.

Dietary anhydrous milk fat naturally enriched with conjugated linoleic acid and vaccenic acid modify cardiovascular risk biomarkers in spontaneously hypertensive rats.

Saturated and trans fatty acids have been associated with the risk to develop cardiovascular diseases. However, health-promoting effects are associated with consumption of anhydrous milk fat (AMF) and ruminant trans fatty acids, such as conjugated linoleic acid (CLA) and vaccenic acid (VA) contained in the lipid fraction of milk and dairy products. The purpose of this study was to evaluate the effect of AMF naturally enriched with CLA and VA in spontaneously hypertensive rats (SHR), using sterculic oil to inhibit the conversion of VA into CLA. The administration of AMF to SHR during 7 weeks exerted beneficial effects on cardiovascular risk biomarkers (reduction of insulin, blood lipids, increase of adiponectin). When sterculic oil was included, some parameters were further ameliorated (reduction of insulin, increase of adiponectin). Sterculic oil alone reduced body weight and adiposity, and improved blood pressure, adiponectin and triglyceride levels.

Chaetognatha in the Bahía Magdalena lagoon complex, Baja California Sur, México: species composition and assemblages.

The chaetognaths from 187 zooplankton samples collected from the Bahia Magdalena lagoon complex, Baja California Sur, Mexico during March, June, July, August, September, November, and December 1982 were studied. Twelve species belonging to two genera were identified. Sagitta euneritica and S. enflata were the most abundant and most frequent species with maximum abundance in July (40,000 org/100 m(3) and 6100 org/100 m(3) respectively). Sagitta pacifica, S. regularis and S. pseudoserratodentata were stenothermic (21 to 25 degrees C), whereas the rest of the species were eurythermic (15.5 to 29.5 degrees C). Sagitta euneritica contributed considerably to the zooplanktonic biomass, increasing the density in particular in BahíaAlmejas. The analysis of the species assemblages (Morisita index) showed that S. pacifica and S. regularis interact more frequently in August when there is a change of the water masses that converge in this zone during summer, when the California Countercurrent predominates. The composition of taxa during winter is characterized by the dominance of S. euneritica. Entering the warm period, an abrupt change occurs in taxa composition of the three zones studied: channels, Bahía Magdalena, and BahíaAlmejas. The amplitude and distribution of S. peruviana was influenced possibility by the oceanographic conditions of ENSO 1982.

[Osteoarticular infections in children: five-year experience]. / Infecciones osteoarticulares en niños: experiencia de cinco años.

BACKGROUND: Osteoarticular infections (IOA) are considered infectious emergencies. The main microorganisms isolated are Staphylococcus aureus and Streptococcus pyogenes. AIM: To describe demographic and clinical characteristics of patients from 2 months to 15 years old, hospitalized between the years 2012 and 2017 with IOA diagnosis. METHODS: Retrospective study in a pediatric hospital. Clinical records of hospitalized patients with IOA were reviewed. RESULTS: 146 met inclusion criteria. 60.3% of the patients were male, median age 3 years 11 months. The main symptom at admission was joint pain (90%) and the median CRP was 43 mg/L. 48% of the patients had microbiological identification; 67.8% were positive for Staphylococcus aureus (10.2% SAMR). 94.5% of the sample received empirical antistaphylococcal beta-lactam treatment and 70,5% had a surgical intervention. Clinical response was observed 72 hours of beginning of treatment, and a decreased in inflammatory laboratory markers was observed at 4.7 days. 88% of patients attended without complications. CONCLUSIONS: IOA infections are more common in boys, S. aureus is the main isolated pathogen, so we suggest to initiate the antimicrobial scheme with an antistaphylococcal beta-lactam, adding broad spectrum antimicrobial in children under 5 years. After 5 days of treatment, clinical resolution and decreased inflammatory laboratory parameters were observed.

Mechanical response of bilayer silicene nanoribbons under uniaxial tension.

Understanding the behaviour of nanoscale systems is of great importance to tailor their properties. To this aim, we investigate the Young's modulus (YM) of defect-free and defective armchair bilayer silicene nanoribbons (SNRs), at room temperature, as a function of length and distance between layers. In this study, we perform molecular dynamics simulations using the environment-dependent interatomic potential to describe the interaction of the Si atoms. We show that the Young's modulus of pristine and defective bilayer SNRs increases with the ribbon length exhibiting size dependence. In general, YM of defective bilayer SNRs is smaller than the value obtained for the defect-free case, as a result of the number of missing bonds. In all cases, as the interlayer distance increases YM decreases and the buckling increases. It is shown that the YM exhibits a quadratic interlayer distance dependence. Finally, when only one layer has a mono-vacancy defect, the atomic stress distribution of the pristine layer is affected by the presence of the vacancy. This effect can be considered as a "ghost vacancy" since the deterioration of the pristine layer is similar to that shown by the defective one. These results show that YM of pristine and defective bilayer SNRs could be tailored for a given length and interlayer distance. It is also found that the fracture stress and the fracture strain of defective bilayers are both smaller than those obtained for the defect-free ones.

Calidad de vida posterior a gastrectomía total laparoscópica versus abierta en cáncer gástrico / Quality of life after -laparoscopic versus open total gastrectomy in gastric cancer

Resumen Introducción: En los últimos años, la gastrectomía laparoscópica ha aparecido como una técnica quirúrgica con resultados oncológicos comparables a la técnica abierta, pero existe poca evidencia en cuanto a la calidad de vida posoperatoria de estos pacientes. Objetivo: Evaluar la calidad de vida posoperatoria de pacientes sometidos a gastrectomía total laparoscópica (GTL) en comparación a gastrectomia total abierta (GTA) en cáncer gástrico. Materiales y Método: Estudio retrospectivo, observacional en Hospital Militar de Santiago, entre enero de 2015 y junio de 2020. Se les aplicó 2 encuestas validadas para Chile: EORTC QLQ-30 y EORTC QLQ-OG25. Resultados: Se obtuvieron 60 pacientes; 30 sometidos a GTL y 30 a GTA. Promedio edad fue 66,3 ± 11 años para GTL y 68,2 ± 11 años en GTA (p = 0,5). Se obtuvo un score en GTL versus GTA: global 83,3 y 80,2 (p = 0,6), sintomático 17,1 y 25,5 (p = 0,2) y score funcional 87,9 y 70,9 (p = 0,03). Posterior a eso obtuvimos en funcionalidad GTL versus GTA; física 92,2 versus GTA 73,1 (p = 0,04), emocional 84,1 versus 78,5 (p = 0,6), cognitiva 84,9 versus 79,0 (p = 0,3) y social 80,9 versus 72,2 (p = 0,4). Al analizar síntomas destaco; fatiga 14,6 versus 33,1 (p = 0,04) y dolor 13,4 versus 24,3 (p = 0,05). Finalmente, en síntomas digestivos altos obtuvimos en disfagia 0,84 GTL versus 17,3 GTA (p = 0,04). Conclusión: La GTL logra resultados comparables a GTA en calidad de vida e incluso ofrece ventajas significativas en funcionalidad física como también en síntomas como dolor, fatiga y disfagia.

Introduction: In recent years, laparoscopic gastrectomy has appeared as a surgical technique with oncological results comparable to the open technique, but there is little evidence regarding the postoperative quality of life of these patients. Objective: To evaluate the postoperative quality of life of patients undergoing laparoscopic total gastrectomy (LTG) compared to open total gastrectomy (OTG) in gastric cancer. Materials and Method: Prospective, observational study at Hospital Militar of Santiago, between January 2015 and June 2020. Two surveys validated for Chile were applied: EORTC QLQ-30 and EORTC QLQ-OG25. Results: 60 patients were obtained; 30 subjected to LTG and 30 to OTG. Average age was 66.3 ± 11 years for LTG and 68.2 ± 11 years for OTG (p = 0.5). A score was obtained in LTG versus OTG: global 83.3 and 80.2 (p = 0.6), symptomatic 17.1 and 25.5 (p = 0.2) and functional score 87.9 and 70.9 (p = 0.03). After that we got LTG versus OTG functionality; physical 92.2 versus 73.1 (p = 0.04), emotional 84.1 versus 78.5 (p = 0.6), cognitive 84.9 versus 79.0 (p = 0.3) and social 80.9 versus 72.2 (p = 0.4). When analyzing symptoms I highlight; fatigue 14.6 versus 33.1 (p = 0.04) and pain 13.4 versus 24.3 (p = 0.05). Finally, in upper digestive symptoms, we obtained 0.84 LTG versus 17.3 OTG in dysphagia (p = 0.04). Conclusion: LTG achieves results comparable to OTG in quality of life and even offers significant advantages in physical functionality as well as symptoms such as pain, fatigue and dysphagia.

Lippia graveolens photochemopreventive effect against UVB radiation-induced skin carcinogenesis.

Lippia graveolens HBK (Mexican oregano) is a species that is regularly used as a condiment in Mexican cuisine. In traditional medicine, it is used for the treatment of respiratory and digestive illnesses, headaches, rheumatism and inflammation-related disorders. The main chemical components reported in this species include the following: terpenoids, iridoids and flavonoids. The aim of this study was to determine the potential photochemopreventive effect of the methanolic extract of Lippia graveolens (MELG) against ultraviolet B (UVB)-induced skin cancer in SKH-1 mice. The phenolic content, radical scavenger activity, penetration and genotoxicity of the MELG were also evaluated. The MELG exhibited scavenging activity against 1,1-diphenyl-2-picrylhydrazyl, superoxide and hydroxyl radicals, and it did not exhibit genotoxic activity in the micronucleus test. In addition, the MELG absorbed UVB (280nm) electromagnetic radiation. The main components detected in the plant extract were naringenin and galangin, and pinocembrin was also isolated and identified through spectroscopic analysis. The MELG demonstrated a photoprotective effect against UVB-induced cell death in Escherichia coli. In chronic challenge experiments, the MELG protected against UVB-induced skin cancer in SKH-1 mice. The MELG penetrated the skin of mice. Topical administration of the MELG protected against chronic UVB-induced damage in mouse SKH-1 skin. Our results suggest that the MELG has photochemopreventive activity and may potentially prevent photo-tumorigenesis.

Molecular characterisation of a dominant methicillin-resistant Staphylococcus aureus (MRSA) clone in a Mexican hospital (1999-2003).

Methicillin-resistant Staphylococcus aureus (MRSA) isolates (n = 216), collected between January 1999 and May 2003 in a tertiary-care university hospital in Guadalajara, Mexico, were characterised by antibiotype, pulsed-field gel electrophoresis (PFGE) of SmaI macrorestriction fragments, and hybridisation of ClaI digests with mecA- and Tn554-specific DNA probes. Representatives of the single clonal type found were analysed by spa typing, multilocus sequence typing and staphylococcal chromosomal cassette mec (SCCmec) typing, and were tested for the presence of 22 virulence determinants and agr type. A single PFGE pattern was identified, with minor variations over time, with spa type 2, sequence type 5, SCCmec type II, agr type 2 and the presence of the enterotoxin genes seg and sei, the gamma-haemolysin variant gene hlg-v and the leukocidin lukE-lukD genes. In addition, the isolates showed antimicrobial resistance to beta-lactams, macrolides, chloramphenicol and imipenem, and susceptibility to gentamicin, rifampicin, trimethoprim-sulphamethoxazole and vancomycin. Following its appearance in 1997, this clone spread within the hospital, and is now present in most of the hospital units and wards.

Determination of early bone metastasis on Bone Scans Using the Gray Levels Histogram / Búsqueda de metástasis ósea temprana en gammagramas óseos usando el histograma de tonos de gris

ABSTRACT The aim of this paper is to show a technique to speed up the interpretation of bone scans in order to determine the presence of early bone metastasis. This is done using the gray levels histogram of the region of interest. The technique is intended to assist in the bone scans interpretation in order to provide a successful diagnosis. During the analysis, three types of histograms were observed on the regions of interest. If the histogram is narrow and shifted toward the origin, the bone scan is free of metastasis. If it is shifted to the right and slightly broadened, indicates the presence of a bone anomaly different from a metastasis. On the other hand, if the histogram is more broadened and shifted to the right, is suggests the presence of metastasis. This histogram is characterized by displaying small curls on the right side providing information about the metastatic disease stage, which could be low-amplitude peaks and have a short length, if the metastasis is in early stage, or high-amplitude peaks and a long length, if is advanced. Finally, the analyzed region is displayed in false color considering the minimum gray levels observed in the histogram.

Combination of dobutamine and myocardial contrast echocardiography to differentiate postischemic from infarcted myocardium.

OBJECTIVES: This study tested whether the combination of dobutamine echocardiography (DE) and myocardial contrast echocardiography (MCE) was superior to either technique alone in identifying postischemic myocardium and in differentiating it from necrotic myocardium. BACKGROUND: Wall motion abnormalities at rest occur in postischemic myocardium in the presence of infarction, stunning or hibernation, alone or in combination. Various investigators have suggested that either DE or MCE can be used to identify the presence of myocardial viability. METHODS: We studied a total of 53 mongrel dogs in an open chest model of coronary occlusion of various durations followed by reperfusion and dobutamine administration (10 microg/kg body weight per min). MCE with aortic root injections of Albunex (area under the curve) and DE (percent thickening fraction) were performed at the different stages. Postmortem triphenyltetrazolium chloride (TTC) staining was used to identify myocardial necrosis. RESULTS: Thirteen dogs underwent brief (15 min) occlusions and developed no necrosis (Group I). Of 40 dogs that underwent prolonged (30 to 360 min) occlusions, 14 had no infarction (Group II), whereas 26 did (Group III: 12 papillary muscle, 7 subendocardial, 7 transmural). MCE (expressed as percent change from baseline) demonstrated changes that paralleled the blood flow changes observed by radiolabeled microspheres at all interventions (r = 0.67, p < 0.0001). Regional ventricular function improved with dobutamine administration in the ischemic region in all three groups. The sensitivity (88%) for detecting myocardial viability was superior when the two techniques were combined; however, a poor specificity (61%) was observed. CONCLUSIONS: Contractile reserve and perfusion data are complementary when assessing regional wall motion abnormalities in postischemic myocardium. DE alone cannot differentiate postischemic from infarcted myocardium; simultaneous data on myocardial perfusion are required. The combination of DE and MCE is superior to either technique alone for identifying the absence of myocardial necrosis.

Electrical activity of prefrontal cortex and ventral tegmental area during rat maternal behavior.

Maternal behavior is a motivated behavior that includes pup-directed sequential motor acts. The dopaminergic (DAergic) brain systems have been proposed to play an important role in voluntary maternal acts, however, not much is known about the way these systems function during the performance of this behavior. The electroencephalogram (EEG) is a sensitive tool that allows determination of the simultaneous functioning of different structures in relation to specific cognitive processes or motor acts. The present study recorded the function of the two structures that constitute the mesoprefrontal DAergic system, ventral tegmental area (VTA) and prefrontal cortex (PFC) by EEG during the performance of various maternal behaviors. Bilateral EEG from the VTA and medial PFC (mPFC) was simultaneously recorded during typical maternal acts and was compared to that recorded during non-maternal behaviors in freely moving female rats. Three different frequency bands (6-7, 8-11, and 12-21 Hz) were obtained from principal component analysis applied to the EEG for both structures. In the left and right mPFC and VTA, absolute power (AP) of the 8-11 Hz band showed a significant increase during pup retrieval compared to the EEG during walking. In the left and right mPFC and VTA, AP of the three bands showed a significant increase during pup licking with respect to forepaw licking. No differences in the EEG were found during inactive nursing behaviors compared to the awake quiet condition. The mPFC and VTA presented characteristic EEG patterns during active maternal behaviors but not during inactive maternal behaviors. This provides electrical evidence of the involvement of these structures in the performance of maternal behavior.

Insulin sensitivity in African-American children with and without family history of type 2 diabetes.

OBJECTIVE: African-Americans are at increased risk for type 2 diabetes. We have previously demonstrated that African-American children are hyperinsulinemic and insulin resistant compared with their white American peers. The aim of the present investigation was to assess the impact of family history of type 2 diabetes on insulin sensitivity in African-American children. RESEARCH DESIGN AND METHODS: A total of 13 prepubertal healthy children with negative family history (FH-) and 9 with positive family history (FH+) of type 2 diabetes underwent a 3-h hyperinsulinemic (40 mU x m(-2) x min(-1))-euglycemic clamp study to assess insulin sensitivity. The groups were comparable for age, pubertal status, total body adiposity determined by dual-energy X-ray absorptiometry, abdominal adiposity assessed by computed tomography scan at the level of L4-5 lumbar vertebra, and physical fitness measured by maximal oxygen consumption (VO2max). RESULTS: The FH+, compared with the FH-, group had lower insulin-stimulated glucose disposal (10.9+/-1.2 vs. 14.2+/-0.9 mg x kg(-1) x min(-1), P = 0.035) and lower nonoxidative glucose disposal (5.7+/-0.8 vs. 8.3+/-0.6 mg x kg(-1) x min(-1), P = 0.015), with no differences in rates of glucose oxidation, fat oxidation, or insulin-mediated free fatty acid suppression. Fasting hepatic glucose production assessed with [6,6-2H2]glucose and basal rates of glucose and fat oxidation were not different between the two groups. CONCLUSIONS: These data suggest that in African-American children, family history of type 2 diabetes is a risk factor for insulin resistance. These children manifest important metabolic alterations, including impaired insulin-stimulated total and nonoxidative glucose disposal early in the first decade of life. We propose that this familial tendency, combined with environmental influences, could lead to type 2 diabetes decades later.

Infecciones osteoarticulares en niños: experiencia de cinco años

Resumen Introducción: Las infecciones osteoarticulares (IOA) son consideradas una urgencia infectológica en niños. Los principales microorganismos causales son Staphylococcus aureus y Streptococcus pyogenes. Objetivo: Describir las características bio-demográficas y clínicas de pacientes de 2 meses a 15 años hospitalizados entre 2012 y 2017 con diagnóstico de IOA. Pacientes y Métodos: Estudio retrospectivo en un hospital pediátrico. Se revisaron fichas clínicas de pacientes internados con diagnóstico de IOA. Resultados: Se incluyó a 146 pacientes. Un 60,3% fueron de sexo masculino, mediana de edad 3 años 11 meses. El síntoma más frecuente al ingreso fue dolor articular (90%) y la mediana de PCR fue de 43 mg/L. Se obtuvo identificación microbiológica en 48%; de ellos, 67,8 % S. aureus (10,2% resistentes a meticilina). El 94,5% de los pacientes recibió de forma empírica β-lactámico anti-estafilocócico. Un 70,5% de los niños requirió procedimiento quirúrgico. A las 72 h se observó respuesta clínica y a los 4,7 días descenso de parámetros inflamatorios de laboratorio. El 88% de los pacientes cursó sin complicaciones. Conclusiones: Las IOA son más frecuentes en varones, el agente infeccioso más frecuentemente identificado fue S. aureus, por lo cual se sugiere inicio del esquema antimicrobiano con un β-lactámico anti-estafilocócico, ampliando cobertura en pacientes bajo 5 años de edad. A los 5 días del tratamiento antimicrobiano ya hay respuesta clínica y descenso de parámetros inflamatorios.

Abstract Background: Osteoarticular infections (IOA) are considered infectious emergencies. The main microorganisms isolated are Staphylococcus aureus and Streptococcus pyogenes. Aim: To describe demographic and clinical characteristics of patients from 2 months to 15 years old, hospitalized between the years 2012 and 2017 with IOA diagnosis. Methods: Retrospective study in a pediatric hospital. Clinical records of hospitalized patients with IOA were reviewed. Results: 146 met inclusion criteria. 60.3% of the patients were male, median age 3 years 11 months. The main symptom at admission was joint pain (90%) and the median CRP was 43 mg/L. 48% of the patients had microbiological identification; 67.8% were positive for Staphylococcus aureus (10.2% SAMR). 94.5% of the sample received empirical antistaphylococcal beta-lactam treatment and 70,5% had a surgical intervention. Clinical response was observed 72 hours of beginning of treatment, and a decreased in inflammatory laboratory markers was observed at 4.7 days. 88% of patients attended without complications. Conclusions: IOA infections are more common in boys, S. aureus is the main isolated pathogen, so we suggest to initiate the antimicrobial scheme with an antistaphylococcal beta-lactam, adding broad spectrum antimicrobial in children under 5 years. After 5 days of treatment, clinical resolution and decreased inflammatory laboratory parameters were observed.

An anthropological approach to the evaluation of preschool children exposed to pesticides in Mexico.

In this comparative study, we compensated for many of the known variables that influence children's growth and development by selecting two groups of 4-5-year-old Yaqui children who reside in the Yaqui Valley of northwestern Mexico. These children share similar genetic backgrounds, diets, water mineral contents, cultural patterns, and social behaviors. The major difference was their exposure to pesticides. Pesticides have been applied to the agricultural area of the valley since the late 1940s. In 1990, high levels of multiple pesticides were found in the cord blood of newborns and in breast milk. Building on anthropological methods for rapid rural appraisal of problems within the environment, a Rapid Assessment Tool for Preschool Children (RATPC) was developed to measure growth and development. The children of the agrarian region were compared to children living in the foothills, where pesticide use is avoided. The RATPC measured varied aspects of physical growth and abilities to perform, or function in, normal childhood activities. No differences were found in growth patterns. Functionally, the exposed children demonstrated decreases in stamina, gross and fine eye-hand coordination, 30-minute memory, and the ability to draw a person. The RATPC also pointed out areas in which more in-depth research on the toxicology of pesticides would be valuable.

Management of blunt splenic trauma: significant differences between adults and children.

BACKGROUND: Although highly successful in children, nonoperative management of blunt splenic injury in adults is less defined. The purpose of this study was to determine whether mechanism of injury, grade of splenic injury, associated injuries, and pattern of injury differ between adults and children (younger than 15 years of age). METHODS: Four hundred eleven patients (293 adults and 118 pediatric patients) with blunt splenic injury were admitted to an affiliated adult/pediatric trauma program from 1989 to 1994. Computed tomography (CT) scans were interpreted in a blinded fashion. Mechanism of injury was significantly different for adults versus children (p < 0.05): motor vehicle crash (66.9% versus 23.7%), motorcycle (8.8% versus 0.8%), sports (2.4% versus 16.9%), falls (8.8% versus 25.4%), pedestrian/automobile (4.4% versus 11.0%), bicycle (1.4% versus 9.3%), and other (7.3% versus 12.7%). RESULTS: Higher injury severity scores, lower Glasgow Coma Scales, and higher mortality indicated that the adults were more severely injured than the children. Fifty-nine percent of the adults and 7% of the children required immediate laparotomy for splenic injury. Both CT grade and quantity of blood on CT predicted the need for exploration in adults but not in children. An injury severity score above 15 and high-energy mechanisms correlated with the need for operative intervention. CONCLUSIONS: Rather than children simply being physically different, they are injured differently than adults, hence the high rate of nonoperative management.

Antimicrobial susceptibilities and capsular types of invasive Streptococcus pneumoniae isolated in children in Mexico City.

As part of the Sistema Regional de Vacunas (SIREVA) initiative, we conducted a surveillance study to determine the relative prevalence of capsular types of Streptococcus pneumoniae and antimicrobial susceptibility of invasive isolates in children less than 5 years old. We collected 220 isolates and found 33 of the 90 known types, with type 23F as the most common followed by types 6A+B, 14, 19F, and 19A. High penicillin resistance was found in 49 strains (22.2%), 31 belonging to type 23F. Twenty-nine (13.1%) were resistant to erythromycin, 95 (43.1%) were resistant to chloramphenicol, and 24 (10.9%) were resistant to cefotaxime. No strains were resistant to vancomycin.

Predominance of the multiresistant 23F international clone of Streptococcus pneumoniae among isolates from Mexico.

During a surveillance study to determine the relative prevalence of capsular types of Streptococcus pneumoniae and antimicrobial susceptibility of invasive isolates in children <5 years old in Mexico City, 220 isolates were collected. The serotype 23F was the most common found, followed by types 6A + B, 14, 19F, and 19A. Diminished susceptibility to penicillin was detected in 106 isolates (48.2%), and high penicillin resistance was found in 49 strains (22.2%), 31 belonging to type 23F. Resistance was also observed to erythromycin (13.1%), to chloramphenicol (43.1%), and to cefotaxime (10.9%). No strains were resistant to ofloxacin or vancomycin. Forty-four of the highly penicillin resistant isolates (penicillin MIC > or =2.0 microg/ml) were examined with molecular fingerprinting techniques; 29 (65.9%) of these isolates (all except two strains) were serotype 23F and shared subtype variants of PFGE type A characteristic of the internationally spread Spanish/USA clone of S. pneumoniae. These strains were also resistant to trimethoprim/sulfametoxasole (TMP/SMX), chloramphenicol, and tetracycline, and most of them were susceptible to erythromycin. Another 6 of the highly penicillin-resistant strains (serogroups 9 and 14) showed PFGE fingerprints and antimicrobial susceptibility pattern characteristic of a second internationally spread clone (French/Spanish clone) and carried resistance to penicillin and TMP/SMX. The rest of the 9 penicillin-resistant isolates were represented by 7 distinct additional PFGE types. The findings suggest that almost 80% of all highly penicillin resistant strains may have been "imported" into Mexico.

Imaging of mediastinal masses in children.

Conventional radiographs show the mediastinum to be the most frequent location of thoracic masses in children. The compartmental approach to evaluation of pediatric mediastinal masses is advised. Compartmental localization and lesion internal characteristics are best determined by cross-sectional imaging techniques. These techniques as well as the causes and significance of the common pediatric mediastinal masses are discussed. Imaging of the thymus is emphasized because normal thymic tissue can mimic pathologic conditions and the thymus is a common thoracic location for neoplasms in children.