Oral cancer knowledge in adults evaluated through a phone survey in the context of the SARS-CoV2 health emergency in Colombia.

BACKGROUND: in Colombia, oral cancer is the eighth most common type of cancer, with an estimated survival rate of 52%. Lack of knowledge about oral cancer and its risk factors is associated with late detection. MATERIAL AND METHODS: a descriptive cross-sectional study was carried out on 268 patients attending the School of Dentistry of the University of Antioquia clinics, to whom a validated 47-question questionnaire was applied by phone during the COVID-19 pandemic (2020 and 2021). Data were analyzed using the SPSS software. RESULTS: the mean age was 58.9. 58.6% of the participants had heard of oral cancer, 42% acquire knowledge from the media, and 96.7% considered screening necessary. Most of the patients expressed not feeling worried (54.5%), fearful (59.7%), or anxious (56.3%) in the case of being submitted to an examination for early detection of oral cancer. A correlation between low socioeconomic status and educational level with less knowledge of oral cancer was found. The dimensions of experience and attitude towards screening were not associated with sociodemographic variables. CONCLUSIONS: There is little knowledge about oral cancer, especially in low socioeconomic and educational status, although this does not occur in the dimensions of attitude and experience toward screening. In contrast, patients participating in this study presented high knowledge about oral cancer risk. This population recognizes the situations most related to the development of cancer. This level of knowledge was similar for the demographic conditions except for people with no education, who presented less knowledge of the risks. The need for educational campaigns on oral cancer knowledge is reaffirmed, especially in socially disadvantaged groups, considering that there would be no barriers related to screening.

Study of out-of-field dose in photon radiotherapy: A commercial treatment planning system versus measurements and Monte Carlo simulations.

PURPOSE: An accurate assessment of out-of-field dose is necessary to estimate the risk of second cancer after radiotherapy and the damage to the organs at risk surrounding the planning target volume. Although treatment planning systems (TPSs) calculate dose distributions outside the treatment field, little is known about the accuracy of these calculations. The aim of this work is to thoroughly compare the out-of-field dose distributions given by two algorithms implemented in the Monaco TPS, with measurements and full Monte Carlo simulations. METHODS: Out-of-field dose distributions predicted by the collapsed cone convolution (CCC) and Monte Carlo (MCMonaco ) algorithms, built into the commercially available Monaco version 5.11 TPS, are compared with measurements carried out on an Elekta Axesse linear accelerator. For the measurements, ion chambers, thermoluminescent dosimeters, and EBT3 film are used. The BEAMnrc code, built on the EGSnrc system, is used to create a model of the Elekta Axesse with the Agility collimation system, and the space phase file generated is scored by DOSXYZnrc to generate the dose distributions (MCEGSnrc ). Three different irradiation scenarios are considered: (a) a 10 × 10 cm2 field, (b) an IMRT prostate plan, and (c) a three-field lung plan. Monaco's calculations, experimental measurements, and Monte Carlo simulations are carried out in water and/or in an ICRP110 phantom. RESULTS: For the 10 × 10 cm2 field case, CCC underestimated the dose, compared to ion chamber measurements, by 13% (differences relative to the algorithm) on average between the 5% and the ≈2% isodoses. MCMonaco underestimated the dose only from approximately the 2% isodose for this case. Qualitatively similar results were observed for the studied IMRT case when compared to film dosimetry. For the three-field lung plan, dose underestimations of up to ≈90% for MCMonaco and ≈60% for CCC, relative to MCEGSnrc simulations, were observed in mean dose to organs located beyond the 2% isodose. CONCLUSIONS: This work shows that Monaco underestimates out-of-field doses in almost all the cases considered. Thus, it does not describe dose distribution beyond the border of the field accurately. This is in agreement with previously published works reporting similar results for other TPSs. Analytical models for out-of-field dose assessment, MC simulations or experimental measurements may be an adequate alternative for this purpose.

Síndrome miasténico congénito por deficiencia de rapsina: reporte de caso con nueva mutación y heterocigosidad compuesta / Congenital myasthenic syndrome due to rapsyn deficiency: A case report with a new mutation and compound heterozygosity

INTRODUCCIÓN Los síndromes miasténicos congénitos son un grupo heterogéneo de desórdenes genéticos, caracterizados por una transmisión sináptica anormal en la placa neuromuscular. REPORTE Presentamos el caso de un paciente de dos años, varón, con hipotonía, ptosis palpebral y debilidad simétrica y de predominio proximal, características que aparecieron desde el nacimiento y que motivaron varias hospitalizaciones por neumonía e insuficiencia ventilatoria. Desde el inicio de la deambulación a los dos años, los padres notaron que la debilidad empeoraba por las tardes y con la actividad física repetida o prolongada. El examen físico a los dos años mostró ptosis palpebral, debilidad de predominio proximal y fatigabilidad con el esfuerzo sostenido. La electro-miografía evidenció decremento del 27% en el potencial de acción muscular compuesto. El análisis de tríos mostró heterocigosis compuesta por transmisión de dos mutaciones diferentes en el gen de rapsina, una ya conocida procedente del padre y la otra no reportada previa-mente, procedente de la madre. El paciente recibió piridostigmina obteniendo mejoría inmediata y logrando un desempeño óptimo en actividades escolares, deportivas y de la vida cotidiana. A la fecha, no ha presentado nuevos episodios de insuficiencia ventilatoria. CONCLUSIONES La debilidad de inicio neonatal y la fatigabilidad o agotamiento con el esfuerzo sostenido, con afección principalmente de los músculos con inervación troncal y con un decremento mayor al 10% en el potencial de acción muscular compuesto en la electromiografía, deben hacer sospechar en un síndrome miasténico congénito. Se revisan los puntos clínicos clave que permiten establecer el diagnóstico oportuno y las opciones de tratamiento efectivo para algunos de estos síndromes.

INTRODUCTION The congenital myasthenic syndromes are a heterogeneous group of genetic disorders characterized by an abnormal synaptic transmission in the neuromuscular plate. REPORT We present a two-year-old patient, male, with hypotonia, palpebral ptosis, and proximal symmetric weakness with a neonatal onset that motivated several and prolonged hospitalizations for pneumonia and respiratory failure. From two years of age, the parents noticed that the facial and general weakness worsened in the afternoons and with repeated or prolonged physical activity. The physical examination showed palpebral ptosis, predominantly proximal weakness, and fatigability with sustained muscular effort. The electromyography showed a 27% decrement in the Compound Muscular Action Potential and the case-parents genetic study showed compound heterozygosity with the transmission of two different mutations in the rapsyn gene from both parents. The patient received pyridostigmine with great improvement, achieving optimal performance in school, sports, and daily life activities. CONCLUSIONS Weakness and fatigability with neonatal onset, mainly affecting the muscles with brain stem innervation and the decrement greater than 10 percent in the Compound Muscular Action Potential in the electromyographic studies, should make us suspect in a congenital myasthenic syndrome. We review the literature and key clinical points to establish a timely diagnosis and effective treatment in some of these syndromes.

Building a network for multicenter, prospective research of central nervous system infections in South America: Process and lessons learned.

Multicenter collaborative networks are essential for advancing research and improving clinical care for a variety of conditions. Research networks are particularly important for central nervous system infections, which remain difficult to study due to their sporadic occurrence and requirement for collection and testing of cerebrospinal fluid. Establishment of long-term research networks in resource-limited areas also facilitates diagnostic capacity building, surveillance for emerging pathogens, and provision of appropriate treatment where needed. We review our experience developing a research network for encephalitis among twelve hospitals in five Peruvian cities since 2009. We provide practical suggestions to aid other groups interested in advancing research on central nervous system infections in resource-limited areas.

The Challenge of Evaluating the Oral Health Status of Older Persons in Latin America.

Knowledge Transfer Statement: This article provides an overview of the oral health status of older people from Latin American countries and the emergence of recent gerodontology research initiatives within the region.

A voxel-based multiscale model to simulate the radiation response of hypoxic tumors.

PURPOSE: In radiotherapy, it is important to predict the response of tumors to irradiation prior to the treatment. This is especially important for hypoxic tumors, which are known to be highly radioresistant. Mathematical modeling based on the dose distribution, biological parameters, and medical images may help to improve this prediction and to optimize the treatment plan. METHODS: A voxel-based multiscale tumor response model for simulating the radiation response of hypoxic tumors was developed. It considers viable and dead tumor cells, capillary and normal cells, as well as the most relevant biological processes such as (i) proliferation of tumor cells, (ii) hypoxia-induced angiogenesis, (iii) spatial exchange of cells leading to tumor growth, (iv) oxygen-dependent cell survival after irradiation, (v) resorption of dead cells, and (vi) spatial exchange of cells leading to tumor shrinkage. Oxygenation is described on a microscopic scale using a previously published tumor oxygenation model, which calculates the oxygen distribution for each voxel using the vascular fraction as the most important input parameter. To demonstrate the capabilities of the model, the dependence of the oxygen distribution on tumor growth and radiation-induced shrinkage is investigated. In addition, the impact of three different reoxygenation processes is compared and tumor control probability (TCP) curves for a squamous cells carcinoma of the head and neck (HNSSC) are simulated under normoxic and hypoxic conditions. RESULTS: The model describes the spatiotemporal behavior of the tumor on three different scales: (i) on the macroscopic scale, it describes tumor growth and shrinkage during radiation treatment, (ii) on a mesoscopic scale, it provides the cell density and vascular fraction for each voxel, and (iii) on the microscopic scale, the oxygen distribution may be obtained in terms of oxygen histograms. With increasing tumor size, the simulated tumors develop a hypoxic core. Within the model, tumor shrinkage was found to be significantly more important for reoxygenation than angiogenesis or decreased oxygen consumption due to an increased fraction of dead cells. In the studied HNSSC-case, the TCD50 values (dose at 50% TCP) decreased from 71.0 Gy under hypoxic to 53.6 Gy under the oxic condition. CONCLUSIONS: The results obtained with the developed multiscale model are in accordance with expectations based on radiobiological principles and clinical experience. As the model is voxel-based, radiological imaging methods may help to provide the required 3D-characterization of the tumor prior to irradiation. For clinical application, the model has to be further validated with experimental and clinical data. If this is achieved, the model may be used to optimize fractionation schedules and dose distributions for the treatment of hypoxic tumors.

Crosstalk between PKCα and Notch-4 in endocrine-resistant breast cancer cells.

The Notch pathway is functionally important in breast cancer. Notch-1 has been reported to maintain an estrogen-independent phenotype in estrogen receptor α (ERα)+ breast cancer cells. Notch-4 expression correlates with Ki67. Notch-4 also plays a key role in breast cancer stem-like cells. Estrogen-independent breast cancer cell lines have higher Notch activity than estrogen-dependent lines. Protein kinase Cα (PKCα) overexpression is common in endocrine-resistant breast cancers and promotes tamoxifen (TAM)-resistant growth in breast cancer cell lines. We tested whether PKCα overexpression affects Notch activity and whether Notch signaling contributes to endocrine resistance in PKCα-overexpressing breast cancer cells.Analysis of published microarray data from ERα+ breast carcinomas shows that PKCα expression correlates strongly with Notch-4. Real-time reverse transcription PCR and immunohistochemistry on archival specimens confirmed this finding. In a PKCα-overexpressing, TAM-resistant T47D model, PKCα selectively increases Notch-4, but not Notch-1, expression in vitro and in vivo. This effect is mediated by activator protein-1 (AP-1) occupancy of the Notch-4 promoter. Notch-4 knockdown inhibits estrogen-independent growth of PKCα-overexpressing T47D cells, whereas Notch-4IC expression stimulates it. Gene expression profiling shows that multiple genes and pathways associated with endocrine resistance are induced in Notch-4IC- and PKCα-expressing T47D cells. In PKCα-overexpressing T47D xenografts, an orally active γ-secretase inhibitor at clinically relevant doses significantly decreased estrogen-independent tumor growth, alone and in combination with TAM. In conclusion, PKCα overexpression induces Notch-4 through AP-1. Notch-4 promotes estrogen-independent, TAM-resistant growth and activates multiple pathways connected with endocrine resistance and chemoresistance. Notch inhibitors should be clinically evaluated in PKCα- and Notch-4-overexpressing, endocrine-resistant breast cancers.

Dental caries prevalence and tooth loss in chilean adult population: first national dental examination survey.

The purpose of this study was to assess the prevalence of dental caries, tooth loss, and risk factors among adult population of Chile. Furthermore, age, gender, and behavioural specific differences in caries prevalence and tooth loss were examined. A national stratified multistage probabilistic sample design in two-age cohorts was applied to the Chilean population. A sample of 1553 adults, comprising 1088 individuals aged 35-44 and 465 senior individuals aged 65-74, were examined. The DMFT was evaluated following WHO recommendations using diagnostic criteria of caries lesions into dentin. The data were analyzed by univariate and multivariate models using logistic regression analyses. Results showed a mean DMFT of 15.06 in the 35-44-year-old group and of 21.57 in the 65-74 group. Factors related to tooth loss in the 35-44 group through univariate logistic regression were depression (OR 1.9 CI 95% 1.26-2.85), education level <12 years (OR 2.24 CI 95% 1.31-3.73), personal income (OR 1.51 CI 95% 1.04-2.19), and familiar income (OR 2.05 CI 95% 1.34-3.13), and through multivariate logistic regression in the same age group were depression (OR 1.93 CI 95% 1.24-3.0), education level <12 years (OR 1.94 CI 95% 1.2-3.14), and familiar income (OR 1.71 CI 95% 1.09-2.68). Factors related to tooth loss in the 65-74-year-old group through univariate logistic regression were education level <12 years (OR 2.54 CI 95% 1.3-4.96) and personal income (OR 1.66 CI 95% 1.05-2.63), and for multivariate logistic regression in the same age group, it was education level <12 years (OR 2.51 CI 95% 1.21-5.18). In conclusion, adult population in Chile showed a high prevalence of dental caries and tooth loss, as age, education level, personal and familiar incomes, and depression are being the main risk factors.

Mesocestoides corti: morphological features and glycogen mobilization during in vitro differentiation from larva to adult worm.

Mesocestodes corti has the capacity to develop from the tetrathyridium (larva) stage to adult worm in vitro by trypsin and serum stimulation. Consequently, it has been used as an experimental model system for studying cestode development, host-parasite relationships and anthelmintic drugs. We describe morphological features in 5 different developmental stages of M. corti obtained in vitro, including larvae from the peritoneal cavity of infected mice, trypsin- and serum-stimulated larvae, elongated parasites as well as segmented and mature worms. It is unambiguously confirmed that sexually mature worms are obtained as a result of this in vitro process of differentiation. Defined cellular regions are present in all stages of development studied, some of them surrounded by a basal lamina. Glycogen is present in the larvae obtained from the mouse peritoneal cavity and in parasites encapsulated in the mouse host liver. Glycogen distribution in the parasite changes on trypsin and serum stimulation to differentiate. We propose that changes in the distribution of neutral polysaccharides in the parenchyma of the parasite at different stages of development and degradation of polysaccharides in the transition from segmented to adult worm are related to energy needs necessary for the cellular processes leading to the mature specimen.

Nonendodontic periapical lesions: a retrospective study in Chile.

AIM: To determine the frequency with which the histopathological diagnosis of periapical lesions contributes to a change in the clinical diagnosis. METHODOLOGY: Cases having a clinical diagnosis of disease resulting from dental pulp necrosis were selected from the database of the Oral Pathology Reference Institute between 1975 and 2005. Cases with different histopathological diagnoses were determined and information about age and gender of the patient, location of associated tooth, pulp status and the histopathological diagnosis were recorded. The percentage of nonendodontic periapical lesions was then determined. RESULTS: In the 30-year period, 32,423 [corrected] biopsy specimens were received. Overall 4006 (9.13%) had a clinical diagnosis of pulpal necrosis with associated pathosis in the periradicular area. Within this group, 26 cases (0.65%) had a histopathological diagnosis of nonendodontic pathology. Keratocystic odontogenic tumour was the most frequent nonendodontic lesion (11 cases) in the periradicular region followed by central giant cell granuloma (three cases), chronic sinusitis (three cases) and one case each of the following lesions: nasopalatine duct cyst, lateral periodontal cyst, calcifying cystic odontogenic tumour, ameloblastic fibroma, squamous odontogenic tumour, cemental dysplasia, haemangioma, foreign body cell granuloma and amalgam tattoo. CONCLUSIONS: The histopathological study of periapical pathosis can occasionally reveal nonendodontic lesions. Odontogenic tumours made up the largest group.

Early post-larval development of the endoparasitic platyhelminth Mesocestoides corti: trypsin provokes reversible tegumental damage leading to serum-induced cell proliferation and growth.

Mesocestoides corti is a suitable in vitro model for studying the development of human endoparasitic platyhelminthes. Treatment with trypsin, supplemented with fetal bovine serum (FBS), induces M. corti development from larvae (tetrathyridia) to segmented adult worm; however, the role of this protease and of FBS in post-larval development induction remains unknown. To characterize the participation of trypsin enzymatic activity and of FBS in the induction of tetrathyridia growth and development, both stimuli were added to the larvae either together or sequentially. Additionally, specific inhibition of trypsin activity was also monitored. Finally, the effect of the enzyme on the parasite tegument as well as the proliferative activity and location of proliferating cells after induction of tetrathyridia development were also studied. We conclude that trypsin-induced tetrathyridia development to adult worm is FBS-dependent and that the effect of serum factors is dependent upon a previous trypsin-induced reversible damage to the larva tegument. In dividing and non-dividing tetrathyridia, proliferative activity of cells is mainly located within the apical massif in the anterior region and nerve cords of larvae, respectively. In tetrathyridia stimulated to develop to adult worms, an intense proliferative activity is evident along the nerve cords. Our results suggest that in natural infections the tetrathyridia tegument is temporally made permeable to growth factors by proteolytic enzyme activity in the intestine juice of the definitive host, thus leading to development to adult worms.

Prevalence of oral mucosal lesions in elderly people in Santiago, Chile.

BACKGROUND: Oral prevalence studies are important to know the state of health and the needs of treatment. Our aim was to determine the prevalence of oral mucosal lesions and associated factors among aging Chileans. METHODS: A random sample by age, gender, and socioeconomic status was obtained, comprising 889 individuals older than 65 years. Individuals were interviewed and examined in Santiago, the capital of Chile, according to the World Health Organization guidelines. RESULTS: The prevalence of one or more oral mucosal lesions in the sample was 53%. Logistic regression model revealed that denture use increased the probability of one or more oral mucosal lesions by threefold, while age, gender, smoking, medication use, xerostomia, and social or cultural factors had no effect. The most common lesion was denture stomatitis (22.3%), followed by irritative hyperplasia (9.4%), oral mucosal varicosities (9%), solitary pigmented lesions (4%), traumatic ulcer (3.5%), angular cheilitis (2.9%), multiple pigmented lesions (2.8%), hemangioma (2.3%), lichen planus (2.1%), leukoplakia (1.7%), recurrent aphthous stomatitis (1.4%), nicotine stomatitis (1.3%), median rhomboid glossitis (0.9%), actinic cheilitis (0.9%), pyogenic granuloma (0.7%), oral squamous papiloma (0.6%), and mucocele (0.2%). One case of oral cancer was observed. Different factors increased the probability of specific oral mucosal pathologies. CONCLUSIONS: We can conclude that oral mucosal lesions are common in elderly people in Santiago, suggesting the necessity for improved standards of prevention, and diagnostic and opportune treatment of these lesions.

A simplified cuture method for blastocystis hominis

Aquí es descrito un método simplificado de cultivo de Blastocystis hominis. Se inocularon doscientas muestras fecales frescas en tubos que contenían un medio de Pavlova modificado. Los tubos herméticos fueron incubados a 36oC sin ningún sistema adicional de anaerobiosis convencional. Los cultivos fueron examinados después de 24, 48 y 72 horas. En conjunto, 140 (70 por ciento) de los cultivos fueron positivos para B. hominis, mientras que el monto del examen microscópico en fresco fue positivo sólo en 42 (21 por ciento) muestras. Se observaron las diferentes formas del parásito descritas con el método estándar. Este método es propuesto como una alternativa al convencional.

[Early maturation: a risk factor of overweight and obesity during puberty?]. / Maduración temprana: factor de riesgo de sobrepeso y obesidad durante la pubertad?

In the Caracas Longitudinal Study, 147 boys and 111 girls--8 to 16 years of age--who had been classified as early, average and late maturers, were analyzed in the context of risk of overweight and obesity. Differences in Body Mass Index (BMI), Arm Circumference (AC), Triceps and Subscapular Skinfolds (TRSK, SSSK) were assessed with an analysis of variance. A significant gradient early > average > late was found girls in all variables throughout follow-up and in AC in boys between 8 and 15 years of age and in BMI until age 11, although early maturers were significantly heavier at all ages. Skinfolds, in boys, presented this significant gradient up to age 11, while in girls it was found in TRSK between ages 8 and 15 and in SSSK between ages 11 and 15. Further analysis of sum of skinfolds, Arm Muscle Area (AMA) and Arm Fat Area (AFA) resulted in significant maturity gradients in girls for all the variables while, in boys, AMA presented this gradient up to age 15, whereas no gradients in and AFA were found from age 12 onwards. Early maturers of both sexes are at risk of overweight; girls are at risk of obesity throughout puberty and boys at prepuberty and early puberty only.

Histone genes in trypanosomatids.

Histone genes in Trypanosomatids are of considerable interest because these flagellates do not condense their chromatin during mitosis. In contrast to higher eukaryotes, histone genes in Trypanosomatids are found on separate chromosomes, and their transcripts are polyadenylated. Sequence similarity of Trypanosomatid core histones with those of higher eukaryotes is found predominantly in the globular region; the N-terminal is highly divergent. Finally, in general, Trypanosomatid histones H1 are of low molecular weight, bearing closest homology to the C-terminal region of the higher eukaryote histones H1. These features constitute interesting targets for a rational approach to the study of these protozoa, as discussed here by Norbel Galanti and colleagues.

Histone H1 and core histones in Leishmania and Crithidia: comparison with Trypanosoma.

The Trypanosomatidae family is characterized by flagellated protozoa presenting a kinetoplast. Several genera of this family contain species that are pathogenic to man and domestic animals. Their chromatin is not condensed into chromosomes during cell division. As a contribution to the understanding of basic aspects of their genome organization, we present a systematic characterization of the histones from three genera of the Trypanosomatidae family. Crithidia fasciculata and Leishmania mexicana show core nucleosomal histones with electrophoretic mobilities both similar to and different from those of Trypanosoma cruzi and higher eukaryotes. Another protein is extracted from the chromatin of these organisms by procedures designed to purify histone H1. This protein presents elution profiles by HPLC and amino acid composition of histone H1. Considering these data and the high mobility of this protein in Triton-acetic acid-urea-polyacrylamide gel electrophoresis, as well as its position relative to the nucleosomal core histones in sodium dodecyl sulfate-polyacrylamide gel electrophoresis, we postulate that Crithidia and Leishmania possess a histone H1 shorter than that of higher eukaryotes as we have previously shown to be the case for T. cruzi. The possible presence of a shorter histone H1 in these trypanosomatids may explain the absence of chromatin condensation during cell division in these flagellates.

Patrones de crecimiento de los venezolanos; dimorfismo sexual y ritmo de maduración / Patterns of growth of the venezuelan sexual dismorphism and rhythm of maturers

Se presentan algunos resultados del Proyecto Venezuela (1981-1987) y del Estudio Longitudinal del Area Metropolitana de Caracas (1976-1983). Las niñas iniciaron el brote puberal (BP) en talla y peso a los 9 1/2 años y alcanzaron la edad del punto de velocidad máxima (EPVM) a los 11 1/2 y 12 años, respectivamente, e iniciaron el desarrollo sexual (GM2) más de 1 año antes que el de los varones (G2:11 1/2 años). Las niñas resultaron más altas y pesadas entre los 11 y 13 años predominio puberal precoz debido al tempo rápido de las venezolanas- los hombres terminaron 12 1/2 cm y 8 Kg más altos y pesados a los 19 años. La secuencia de eventos: EPVM talla

[Estimation of the menarcheal age in a longitudinal study: comparison of methods]. / Estimación de la edad de la menarquia en un estudio longitudinal: comparación de métodos.

Menarcheal age was assessed in 164 girls followed longitudinally for six years, belonging to Caracas upper social strata. The retrospective, prospective and "Status Quo" methods were used; age was recorded as the recalled date, the mid-interval interpolated date and the age at examination; and called "real" age (RA), "interval" age (IA) and "visit" age (VA). Means were calculated and medians estimated using the Logit method. Means of differences between RA and VA and between IA and VA were similar: 0.4 years approximately and significantly greater than the corresponding mean between RA and IA (0.2 years), thus mid-interval and RA mean menarcheal ages were similar. Values ranged from 12,866 to 12,341 with a standard deviation of one year. Mean menarcheal "visit" age was significantly later than both IA and RA means. Median menarcheal VA using the "Status Quo" and the Logit methodologies, was 12,337 +/- 0.028, similar to "real" age, and has been chosen for further analysis and correlations. The results are consistent with the low menarcheal age values reported for Venezuela.

Cerebral blood flow increases during insulin-induced hypoglycaemia in type 1 (insulin-dependent) diabetic patients and control subjects.

The effect of insulin-induced hypoglycaemia on cerebral blood flow was examined using the intravenous xenon-clearance technique in 9 patients with Type 1 (insulin-dependent) diabetes (aged 20 to 43 years) and 9 age-matched control subjects before, during and after hypoglycaemia. Cerebral blood flow rose in both groups. The mean basal cerebral flood flow values were not significantly different and during hypoglycaemia mean cerebral blood flow increased by 17% (p = 0.008) in the diabetic patients and by 21% (p = 0.0003) in the control subjects. The results suggest that in young diabetic patients without autonomic neuropathy or microangiopathy cerebral vessels dilate normally in response to hypoglycaemia. The physiological importance of an increase in cerebral blood flow during hypoglycaemia is uncertain; but glucose availability is increased.

High levels of growth hormone and human placental lactogen in pregnancy complicated by diabetes.

The possible involvement of growth hormone (GH) and human placental lactogen (HPL) in the development of diabetic tissue damage during pregnancy was studied in 16 insulin-dependent diabetic patients (IDDM), 8 gestational diabetic patients (GD) and 14 normal pregnant women. GH and HPL were elevated in pregnancies complicated by diabetes but, in contrast to the rise of HPL, GH declined throughout pregnancy in all the groups studied. The concentrations of neither correlated with plasma glucose, insulin requirement or duration of diabetes. HPL was positively correlated with urinary albumin excretion (UAE) in all 3 groups, but with blood pressure only in the IDDM group. There was also a significant and positive correlation in all patients between HPL at the end of pregnancy and placental weight. No evidence of serious tissue damage was found in either diabetic group. The vibration sensory threshold was unaffected by pregnancy and was similar to that of normal women. However, in the IDDM group UAE increased significantly postpartum when compared with second trimester values; they also had higher UAE than the other 2 groups post-delivery. A small but significant rise in diastolic blood pressure (DBP) was found in the 3 groups studied between the second and third trimester and pre-delivery. The same trend in systolic blood pressure (SBP) was seen in the diabetic groups. The IDDM had higher systolic and diastolic blood pressures than the normal women at all stages of gestation.