The athlete gut microbiota: state of the art and practical guidance

The gut microbiota has been proposed to grant the athlete a metabolic advantage that might be key when optimising performance. While a taxonomic core set of microorganisms characterising the athlete's gut microbiota has not been delineated, some compositional features might be associated with improved metabolic efficiency, which appears to be driven by the production of bacterial metabolites, such as short-chain fatty acids. Not only long-term exercise but also dietary patterns associated with high-level sports practice contribute to this microbial environment, yet isolating the impact of individual dietary components is challenging. The present review synthetises the available evidence on the compositional aspects of the athlete's gut microbiota, discusses mechanisms involved in the bidirectional association between exercise and the gut environment, and evaluates the role of athletes' diet in this interplay. Additionally, a practical approach to indicators commonly reported in metagenomic and metabolomic analyses is provided to explore how these insights can translate to support dietary protocols.

A systematic review of breast milk microbiota composition and the evidence for transfer to and colonisation of the infant gut

The intestinal microbiota plays a major role in infant health and development. However, the role of the breastmilk microbiota in infant gut colonisation remains unclear. A systematic review was performed to evaluate the composition of the breastmilk microbiota and evidence for transfer to/colonisation of the infant gut. Searches were performed using PUBMED, OVID, LILACS and PROQUEST from inception until 18th March 2020 with a PUBMED update to December 2021. 88 full texts were evaluated before final critique based on study power, sample contamination avoidance, storage, purification process, DNA extraction/analysis, and consideration of maternal health and other potential confounders. Risk of skin contamination was reduced mainly by breast cleaning and rejecting the first milk drops. Sample storage, DNA extraction and bioinformatics varied. Several studies stored samples under conditions that may selectively impact bacterial DNA preservation, others used preculture reducing reliability. Only 15 studies, with acceptable sample size, handling, extraction, and bacterial analysis, considered transfer of bacteria to the infant. Three reported bacterial transfer from infant to breastmilk. Despite consistent evidence for the breastmilk microbiota, and recent studies using improved methods to investigate factors affecting its composition, few studies adequately considered transfer to the infant gut providing very little evidence for effective impact on gut colonisation.

Dorsal Vascular Complex Nonligation Method and Preservation of Puboprostatic Ligaments and Endopelvic Fascia During Laparoscopic Radical Prostatectomy: Effect on Continence

OBJECTIVE

To evaluate the impact on continence rate during 1-year follow-up of a preservation technique that included nonligation of the dorsal vascular complex and sparing of the puboprostatic ligaments and the endopelvic fascia during laparoscopic radical prostatectomy.

MATERIAL AND METHODS

Information from 30 patients who underwent the preservation technique was prospectively collected and compared with data from 60 patients who underwent the nonpreservation traditional technique. A single surgeon performed all procedures.

RESULTS

Demographic and preoperative characteristics were similar. The mean patient age was 59 years in both groups. All patients were stage cT1c or cT2. Operative time was significantly lower in the preservation technique group (229.6 vs. 262.7 minutes, P < .001). There were no significant differences in intraoperative bleeding, discharge hemoglobin level, blood transfusion rate, length of hospitalization, and drop in the hemoglobin level. The probability of continence recovery was significantly higher in the preservation technique group than in the traditional technique group (hazard ratio = 0.50, 95% CI = 0.31-0.81). The continence rate (0 pads/day) for the preservation technique group versus the traditional technique group at 1, 3, 6, and 12 months was, respectively, 53.3% versus 30% (P = .031), 90% versus 45% (P < .001), 90% versus 63.3% (P = .008), and 96.6% versus 78.3% (P = .024). There were no significant differences between the groups regarding potency and oncologic outcomes.

CONCLUSION

Nonligation of the dorsal vascular complex and preservation of the puboprostatic ligaments and the endopelvic fascia improved urinary continence compared with the traditional nonpreservation technique, with no impact in terms of bleeding and oncologic outcomes.

Prospective evaluation of the association between varicocele and benign prostatic hyperplasia in men over 40 years of age

We investigated the association between varicocele and benign prostatic hyperplasia in men over the age of 40 years. A total of 296 outpatients were evaluated. Prostate volume was measured with transrectal ultrasound. Varicocele was diagnosed by physical examination and ultrasound. Prostatic hyperplasia was defined as prostate volume greater than or equal to 40 ml. Two groups were compared: patients with prostate volume less than 40 ml and patients with prostate volume greater than or equal to 40 ml. There was a statistically significant difference between the groups in terms of mean age, post-void residual, International Prostate Symptom Score and PSA. The percentage of patients with clinical varicocele in the group with a volume less than 40 ml and the group with a volume equal to or greater than 40 ml was 38.2% and 47.7% respectively (p = .12). There were no differences between the two groups in the percentage of patients with clinical or subclinical varicocele (43.2% vs. 52.2%, respectively, p = .12). No differences were found in the percentage of patients with varicocele when comparing men with prostates smaller than 40 ml and greater than or equal to 40 ml.

Role of Oral Nutritional Supplements Enriched with β-Hydroxy-β-Methylbutyrate in Maintaining Muscle Function and Improving Clinical Outcomes in Various Clinical Settings

Aging and disease-related malnutrition are well associated with loss of muscle mass and function. Muscle mass loss may lead to increased health complications and associated increase in health care costs, especially in hospitalized individuals. High protein oral nutritional supplements enriched with β-hydroxy-β-methylbutyrate (HP-ONS+HMB) have been suggested to provide benefits such as improving body composition, maintaining muscle mass and function and even decreasing mortality rates. The present review aimed to examine current evidence on the effect of HP-ONS+HMB on muscle-related clinical outcomes both in community and peri-hospitalization patients. Overall, current evidence suggests that therapeutic nutrition such as HP-ONS+HMB seems to be a promising tool to mitigate the decline in muscle mass and preserve muscle function, especially during hospital rehabilitation and recovery.

Maternal Body Weight and Gestational Diabetes Differentially Influence Placental and Pregnancy Outcomes

CONTEXT

Maternal obesity and gestational diabetes mellitus (GDM) can both contribute to adverse neonatal outcomes. The extent to which this may be mediated by differences in placental metabolism and nutrient transport remains to be determined.

OBJECTIVE

Our objective was to examine whether raised maternal body mass index (BMI) and/or GDM contributed to a resetting of the expression of genes within the placenta that are involved in energy sensing, oxidative stress, inflammation, and metabolic pathways.

METHODS

Pregnant women from Spain were recruited as part of the "Study of Maternal Nutrition and Genetics on the Foetal Adiposity Programming" survey at the first antenatal visit (12-20 weeks of gestation) and stratified according to prepregnancy BMI and the incidence of GDM. At delivery, placenta and cord blood were sampled and newborn anthropometry measured.

RESULTS

Obese women with GDM had higher estimated fetal weight at 34 gestational weeks and a greater risk of preterm deliveries and cesarean section. Birth weight was unaffected by BMI or GDM; however, women who were obese with normal glucose tolerance had increased placental weight and higher plasma glucose and leptin at term. Gene expression for markers of placental energy sensing and oxidative stress, were primarily affected by maternal obesity as mTOR was reduced, whereas SIRT-1 and UCP2 were both upregulated. In placenta from obese women with GDM, gene expression for AMPK was also reduced, whereas the downstream regulator of mTOR, p70S6KB1 was raised.

CONCLUSIONS

Placental gene expression is sensitive to both maternal obesity and GDM which both impact on energy sensing and could modulate the effect of either raised maternal BMI or GDM on birth weight.

Quantitative determination of β-hydroxymethylbutyrate and leucine in culture media and microdialysates from rat brain by UHPLC-tandem mass spectrometry

The main objective of the present work was to develop a method to determine β-hydroxymethylbutyrate (HMB) and leucine (Leu) in culture media and brain microdialysates. An accurate, selective, and cost-effective method, based on the use of ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS), was developed for the identification and quantification of both compounds. The method consisted of sample dilution, direct injection onto the chromatographic equipment, and quantification with a triple quadrupole mass spectrometer using an electrospray ionization interface in positive mode. The procedure and the UHPLC-MS/MS parameters were accurately optimized to achieve the highest recoveries and to enhance the analytical characteristics of the method. For chromatographic separation, an Acquity UPLC BEH Hilic column using acetonitrile-water gradient with formic acid as additive was employed. The total run time was 4 min. The limits of detection (LODs) obtained ranged from 0.01 to 0.04 μg mL(-1), and the limits of quantification (LOQs) ranged from 0.04 to 0.12 μg mL(-1). Precision (expressed as relative standard deviation) was lower than 15 %, and the determination coefficient (R (2)) was higher than 99.0 % with a residual deviation for each calibration point lower than ±25 %. Mean recoveries were between 85 and 115 %. The method was successfully applied to the analysis of both compounds, HMB and Leu, in samples obtained from an experiment of blood-brain barrier (BBB) passage in vitro and to an experiment of brain microdialysis in rats in vivo after an oral challenge with HMB to detect its appearance in the brain.

Ultra high performance liquid chromatography-tandem mass spectrometry method for the determination of soluble milk glycans in rat serum

The main objective of the present work was to develop and validate a multicompound method to measure soluble milk glycans (SMGs) in biological fluids such as serum. An ultra high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method for the identification and quantification of the following SMGs and their precursors 2'-fucosyllactose, 3'-sialyllactose, 6'-sialyllactose, lacto-N-neotetraose, N-acetylneuraminic acid, fucose, lactose and glucose in rat serum samples was set up. These analytes were separated in an Acquity UPLC BEH Amide column using acetonitrile-water gradient with ammonia as additive, in a 10 min run, and were detected and quantified using a triple quadrupole (QqQ) mass spectrometer. The mass spectrometric conditions in negative electrospray ionization mode (ESI-) were individually optimized for each analyte to obtain maximum sensitivity in the Selected Reaction Monitoring (SRM) mode. Selection of two specific fragmentation reactions for each compound allowed simultaneous quantification and identification in one run, ensuring a high specificity of the method. The limits of detection (LODs) ranged from 5 to 70 ng mL(-1) and the limits of quantification (LOQs) from 20 to 200 ng mL(-1). The inter- and intra-day variability was lower than 15% and the recoveries ranged from 85% to 115%. A biological application of the method was also described, specifically the time-course of SMGs in rat serum after an oral challenge.

Quantitative determination of neurotransmitters, metabolites and derivates in microdialysates by UHPLC-tandem mass spectrometry

The main objective of the present work is to study the time-course of rat brain neurotransmitters in vivo after an oral challenge with a nutritional ingredient or an external stimulus, such as a chemical agent. An ultrahigh performance liquid chromatography-tandem mass spectrometry method for the identification and quantification of neurotransmitters, metabolites and derivates in microdialysates from rat brain was previously developed. Betaine, glutamine, glutamic acid, gamma-aminobutyric acid, phosphocholine, glycerophosphocholine, cytidine 5'-diphosphocholine, choline, acetylcholine, dopamine, norepinephrine, serotonin, tyrosine, epinephrine, tryptophan and 5-hydroxyindoleacetic acid were selected as analytes. The method involves direct injection of samples of microdialysates from rat brain onto the chromatographic equipment and quantification with a triple quadrupole mass spectrometer detector using an electrospray ionization interface in positive mode. The limits of detection ranged from 0.1 to 50 ng mL(-1) and the limits of quantification from 0.3 to 200 ng mL(-1). The inter- and intra-day variability were lower than 15%. Recovery rates ranged from 85% to 115%.

Intestinal toxicity induced by 5-fluorouracil in pigs: a new preclinical model

BACKGROUND

The goal of this study was to develop an animal model of intestinal injury induced by 5-fluorouracil (5-FU) in pigs.

METHODS

Six domestic pigs were used as control (healthy group) and another 6 malnourished pigs orally received 5-FU (treated group). After 4 weeks of treatment, pigs were sacrificed and jejunum, ileum and colon were isolated for histological, immunological and biochemical analyses.

RESULTS

5-FU caused a decrease in the intestinal mass. Disaccharidase, and phosphate alkaline activities, and glutathione redox cycle were disrupted by 5-FU. Histopathological alterations in the crypts and villous were greater in the small intestine than in the colon. 5-FU decreased the number of peripheral and intestinal leukocytes, promoting an increase in T-cytotoxic cells and a decrease in T-helper and B cells.

CONCLUSION

This pig model of intestinal dysfunction closely mimics the common side effects of cancer chemotherapy in humans, and provides a useful tool for evaluating novel antimucotoxic agents.

Ribonucleotides: conditionally essential nutrients shown to enhance immune function and reduce diarrheal disease in infants

It remains a goal of pediatric nutrition to provide optimal nourishment for infants who are not fed human milk. Investigators have attempted to emulate the composition and functionality of human milk, the gold standard for infant nutrition. These efforts began with the analysis of milk components and continued with assessments of biological effects that culminated in clinical studies in infants. This chapter summarizes the path that researchers followed to study ribonucleotides and their role in infant nutrition. Based on analytical methods for the quantification of ribonucleotides in human milk, investigators assessed their potential impact on the immune systems of infants and looked for concomitant mechanistic explanations. These inquiries evolved into clinical trials in which ribonucleotide-supplemented formula performance was compared with that of non-supplemented formulas and with human milk. This chapter intends to summarize an area of pediatric nutrition that has yielded both enlightening evidence and seemingly contradictory data.

Dietary gangliosides positively modulate the percentages of Th1 and Th2 lymphocyte subsets in small intestine of mice at weaning

We studied the influence of dietary gangliosides on the number of spontaneous cytokine-secreting cells from two intestinal lymphocyte populations: lamina propria lymphocytes and Peyer's patches lymphocytes in Balb/c mice for 28 days after weaning. Weanling mice were separated into two groups, designated as Control and BG. The Control group was fed with a semipurified diet without gangliosides and the BG group was fed with the semipurified diet supplemented with 47 mg/kg of a mixture of bovine brain gangliosides. Intestinal lymphocytes were isolated from mice killed at 3, 7, 14 and 28 days after weaning, and the percentages of spontaneous Th1 as well as Th2 cytokine-secreting lymphocytes were determined using the ELISPOT assay. The BG group animals showed an earlier development in the number of cytokine-secreting cells, which appeared one week later in Control animals. In addition, mice fed with the ganglioside-supplemented diet showed a significantly higher number of Th1 and Th2 cytokine-secreting lymphocytes than Control mice in lamina propria and Peyer's patches lymphocytes at the end of the experimental period (28 days). Our results suggest that dietary gangliosides influence the maturation process of the intestinal immune system that take place during weaning.

Gestational age and origin of human milk influence total lipid and fatty acid contents

The human milk composition may be influenced by several factors, such as gestational age or genetic characteristics and dietary habits of different populations. To analyze the total lipid and fatty acid contents of human milk, we have conducted two studies, one on mothers who had delivered preterm and term newborns and another on mothers from two different sociocultural backgrounds (Spain and Panama). The total lipid content (g/100 g wet weight) was significantly higher in term (2.76 +/- 0.66; mean +/- SD) than in preterm mature milk (1.06 +/- 0.4). The relative amount of 18:1n-9 was significantly higher in preterm than in term milk for transitional and mature milk, whereas that for the colostrum followed the opposite trend. Concerning the comparison between milk from mothers born in different countries, the relative contents of each of the fatty acids 16:0, 16:1n-7, 18:2n-6, 18:3n-3, and 22:5n-3 were higher in Panamanian than in Spanish milk, whereas the mean percentages of saturated fatty acids < 14:0, of 16:1n-9, and of 18:1n-9 were higher in Spanish than in Panamanian milk. Statistically significant differences were found during the three periods of lactation considered for almost all the fatty acids mentioned above, especially for 18:1n-9 and 18:3n-3. Although the potential biological significance of the changes in oleic acid content between preterm and term milk remains unclear, differences in fatty acid content between Spanish and Panamanian milk reflect the different composition of the diet among women from these countries.

Weaning induces an increase in the number of specific cytokine-secreting intestinal lymphocytes in mice

Intestinal immunity differs from systemic immunity in several aspects and is frequently studied separately. In this work we have analysed the frequency of mononuclear cells spontaneously secreting the cytokines IL-2, IL-4, IL-5, IL-6, IL-10, interferon gamma (IFN-gamma) and tumour necrosis factor (TNF-alpha), in Peyer's patches and lamina propria of small intestine in mice by enzyme linked immunosorbent spot (ELISPOT) during 1 month after weaning. We have found a high percentage of spontaneous Th(1)as well as Th(2)cytokine-secreting lymphocytes in both populations, Peyer's patches and lamina propria. An increase in the number of the lymphocytes secreting most of the studied cytokines, at 1 and 2 weeks after weaning, was also observed. These results suggest that the increase in the number of cytokine secreting lymphocytes may be one of the potential mechanisms involved in the development of the intestinal immune system at weaning.

The development and construct validation of a Spanish version of an Academic Self-Concept scale for middle school Hispanic students from families of low socioeconomic levels

For a sample of 305 6th, 7th and 8th grade students, of whom 95% was from economically disadvantaged Hispanic families and for whom English was their second language, evidence was sought regarding the reliability and construct validity of scores on a Spanish version of an academic self-concept measure entitled Dimensions of Self-Concept (DOSC), comprising five subscales bearing the same names as those of the five hypothesized constructs that they were intended to operationalize: Level of Aspiration, Anxiety, Academic Interest and Satisfaction, Leadership and Initiative, and Identification versus Alienation. Reliability estimates varying between .72 and .80 were judged to be reasonably satisfactory. Results from oblique factor analysis lent empirical support for the hypothesized constructs of Anxiety, Leadership and Initiative, and Identification versus Alienation. Scores associated with the subscales of Level of Aspiration and Academic Interest and Satisfaction generated a factor interpreted as a fusion of the two constructs of Level of Aspiration and Academic Interest and Satisfaction.

[Giant subarachnoid cysts due to neurocysticercosis: two cases reported fro a rural area in Extremadura]

INTRODUCTION

Neurocysticercosis is the commonest cerebral parasitosis. The most recent cases reported in Spain have occurred in patients from endemic countries. The formation of giant subarachnoid cysts (GSC) is an uncommon complication of neurocysticercosis and its treatment is the subject of debate. We report two cases seen recently in the Valle del Jerte, a rural district in Extremadura.

CLINICAL CASES

Case 1. A 64 year old man had had complex partial crises (CPC) since 1985. In 1987 he was diagnosed as having neurocysticercosis with parenchymatous cysts and treated with praziquantel. In 1996, on CAT and MR a left frontal GSC was diagnosed and also two parenchymatous active cysts. The cyst was removed surgically and he was subsequently treated with albendazol. Case 2. A 72 year old man had generalized crises and CPC since 1970. In 1987 and 1991 on CAT and MR several parenchymatous lesions compatible with neurocysticercosis were seen. In 1997 he presented with headache and subacute cognitive impairment. On CAT and MR a left temporal GSC was seen with several active parenchymatous lesions. The patient was treated with albendazol and dexamethasone. Both patients improved, although radiological resolution of the GSC in case 2 took a year.

CONCLUSIONS

Neurocysticercosis is a condition still present in Spain. GSC respond to treatment with albendazol, whilst surgical treatment is the best option when severe intracranial hypertension occurs.

Neonatal dietary gangliosides

Gangliosides are glycosphingolipids that are widely distributed in vertebrate tissues and body fluids and which are specially abundant in neural tissues. Milk from different species has a particular ganglioside content and profile. Human milk has a higher content of gangliosides than bovine milk. GD3 and GM3 are the predominant individual gangliosides in bovine milk. In human colostrum GD3 is also the main ganglioside whereas in human mature milk GM3 predominates over the other gangliosides. Human milk also contains GM1 and a number of highly polar gangliosides, which may play an important role in infant physiology. GM1 has been shown to inhibit Escherichia coli and Vibrio cholerae enterotoxins. We have found that a ganglioside-supplemented infant formula modifies the intestinal ecology of preterm newborns, increasing the Bifidobacteria content and lowering that of Escherichia coli. Although the exact mechanism by which dietary gangliosides reduce the fecal content of Escherichia coli is unknown, in vitro experiments suggest that they may act as false intestinal receptors for some strains of this bacteria. Since GD3 and other gangliosides have been involved in mechanisms of lymphocyte activation and differentiation, dietary gangliosides might have a function in intestinal immunity development.

Addition of gangliosides to an adapted milk formula modifies levels of fecal Escherichia coli in preterm newborn infants

Because some gangliosides bind bacteria, we tested the influence of supplementating an adapted milk formula with gangliosides, at a total concentration of 1.43 mg/100 kcal, on the fecal microflora of preterm infants. At all sampling times, feces from infants fed with ganglioside-supplemented formula had significantly lower relative content of Escherichia coli than feces from infants fed with control milk formula: the difference was especially significant at age 7 days postnatal < .001). At age 30 days postnatal, fecal bifidobacterial counts were higher in infants fed with ganglioside-supplemented formula (P < .05). We conclude that gangliosides at concentrations present in human milk significantly modify the fecal flora.

Developmental changes in UDP-N-acetylglucosamine 2-epimerase activity of rat and guinea-pig liver

The activity of UDP-N-acetylglucosamine 2-epimerase was determined in the liver of rats and guinea-pigs of different ages. The activity of this enzyme in rats was low at birth, increased to a maximum value on day 15, and fell gradually until day 30. Thereafter, it increased up to the 60th day. The activity profile of the enzyme from guinea-pig liver was very similar. However, guinea-pig activity was 2-5 times lower than in rats. Both rats and guinea-pigs displayed similar liver sialic acid contents which increased from birth to 2 months of age. Rats also showed a N-glycolylneuraminic acid content that decreased from birth to 2 months. From these results we can inferred that postnatal UDP-N-acetylglucosamine 2-epimerase activity seems to be correlated with age and the developmental states of rats and guinea-pigs.

Changes during lactation in ganglioside distribution in human milk from mothers delivering preterm and term infants

We studied changes during lactation in the relative concentration of individual gangliosides in human milk from mothers delivering preterm and term infants. The relative content of G(D3) was higher in colostrum than in mature milk, and tended to be higher in preterm colostrum than in term colostrum, whereas the relative content of G(M3) was higher in mature milk than in colostrum, and was also higher in term than in preterm milk. As G(D3) is usually detected in developing tissues whereas G(M3) is more abundant in mature tissues, these results suggest a relationship between the presence of individual gangliosides in human milk and immaturity of the mammary gland in mothers of preterm infants.

Comparison of content and distribution of human milk gangliosides from Spanish and Panamanian mothers

The lactational changes in content and distribution of gangliosides in human milk from Spanish and Panamanian mothers delivering term newborns were studied. There were no statistically significant differences in the concentration of gangliosides between Spanish and Panamanian milk. The ganglioside content expressed as a function of total milk lipids tended to decrease as lactation progressed in both types of milk. There was a significant correlation (r = 0.5896; p = 0.0062) between ganglioside and total lipid contents in Panamanian milk. However, in Spanish milk, the correlation was not significant (r = 0.1516; p = 0.3439). We did not detect important differences in the relative concentrations of individual gangliosides during lactation among milk samples from Spanish and Panamanian mothers. For both of them, GD3 was the most abundant ganglioside in colostrum, whilst in mature milk it was GM3.

Bilingual special education teachers' shifting paradigms: complex responses to educational reform

This study examined the nature and process of change among five bilingual special education teachers as they attempted to modify existing instructional practices. Three factors affected the change process: (a) The more special education training in the teachers' background, the stronger their reductionist orientation; (b) change involves shifts in instructional practices and shifts in beliefs, and they do not automatically go hand in hand; and (c) change is most facilitated at the beginning stages of collaboration by including practicing members of the teachers' occupational community as agents of change.

New data on content and distribution of gangliosides in human milk

The content and distribution of gangliosides, and total lipid content, were studied in human milk samples from different periods of lactation. We found a significant correlation (r = 0.5564; p = 0.0165) between ganglioside and total lipid contents. There was a selective change in the relative concentrations of GD3 and GM3 during lactation. The most abundant ganglioside in samples from the first three weeks of lactation was GD3, whereas after the first month, GM3 was the major ganglioside. In addition to GD3 and GM3, previously known to be present in human milk, we detected several previously unreported highly polar gangliosides.

Changes in ganglioside and sialic acid contents of goat milk during lactation

The ganglioside content of goat milk has been determined from d 1 after parturition to d 60 of lactation. Marked changes occurred in milk over the course of lactation; the highest ganglioside content occurred in d-1 colostrum and then decreased to the end of the period studied. At least seven different ganglioside species were detected; three gangliosides containing sialyllactosylceramide accounted for 66 to 92% of the total lipid-bound sialic acid; this result reflected a very simple core structure of goat milk gangliosides. The most abundant ganglioside, II3(N-acetylneuraminic acid)2-lactosylceramide, was about 35 to 56%. The sialic acid content exhibited a trend similar to that of gangliosides; during early lactation sialic acid content was higher than in mature milk. Fat, protein, and total solids were high at initiation of lactation and decreased thereafter. However, lactose content remained almost unchanged during the period studied.

Detection of complex gangliosides in human amniotic fluid

Gangliosides are possibly very potent immunosuppressive molecules. Here we show that human amniotic fluid contains high concentrations of a number of previously unnoted, structurally complex and highly polar gangliosides. These unusual molecules are present early in pregnancy (first trimester), increase in concentration with gestational age, and reach maximum levels (0.8 microM) at term. Since similar gangliosides have been detected in human placenta, trophoblast, and amnion, we suggest that these molecules are shed into the amniotic fluid bathing these tissues.

Detection of immunoregulatory lipid-like factors in human amniotic fluid

The immunosuppressive activity of amniotic fluid (AF) is extensively documented in the mouse. Although this property is due in part to the presence of alpha-fetoprotein (alpha-FP), other immunosuppressive factors are suspected. In this article, we demonstrate that human amniotic fluid lipid extract (AFLE) is inhibitory of, although not cytotoxic to, PHA-activated human lymphocytes, of mouse bone marrow cells, and of different established cell lines of human and mouse source. This effect is shown to be reversible. Under preparative thin layer chromatography (TLC) using chloroform:methanol:water (60:38:8) as solvents, the activity of AFLE migrates to two peaks of inhibition with Rf values of 0.46-0.62 and 0.84-1, respectively. These lipid-like factors may play a role as a nonspecific immunoregulatory mechanism which prevents maternally mediated immune rejection of the conceptus.

Decreased levels of circulating CD4+ T lymphocytes during normal human pregnancy

Peripheral blood mononuclear cell (PBMC) populations during human pregnancy have been investigated by many authors, although the different results obtained, principally in relation to T cells, are very discrepant. In this study we aimed to exclude all the possible causes of these discrepancies: small sample size; diurnal rhythm of CD4+ T cells; smoking habits; haemodilution which occurs during pregnancy and inappropriate statistical analysis; in order to determine whether gestation has a definite effect on PBMC populations. We found that the percentage of CD4+ T lymphocytes decreases in the first and second trimesters, returns to the non-pregnant level in the third trimester and remains there in the postpartum period. The percentages of CD3+ T lymphocytes run parallel to those of CD4+ while CD8+ T lymphocytes do not vary. The proportion of CD16+ cells, which include mature NK cells, diminishes in the second trimester and this reduction is maintained in the third trimester and the puerperium. No variation was found in the other PBMC studied (CD20+ lymphocytes, CD14+ monocytes and D/DR+ cells). When parity was considered no difference was seen between primiparous and multiparous women in any of the cell populations tested.

Interpersonal tactics and communicative strategies of Anglo-American and Mexican-American mildly mentally retarded and nonretarded students

In this investigation, we compared the preferred interpersonal tactics of mildly mentally retarded Mexican-American and Anglo-American children in an experimental social problem-solving situation. Sixty subjects were divided into four equal groups based upon ethnicity (Mexican-American or Anglo-American) and educational status (mildly mentally retarded or nonretarded). Results indicated that although there were no ethnic group differences, differences in preferred problem solving strategies were demonstrated by mentally retarded and nonretarded children. Overall, nonretarded children tended to utilize strategies such as cooperation and temporary withdrawal more often than mentally retarded children.

Referential communication skill levels of moderately mentally retarded adolescents

Referential communication skills of moderately mentally retarded adolescents (20 speaker-listener dyads) were investigated. In Study 1, subject performance on referential communication activities divided into three skill levels requiring sampling, comparison, and critical-features analysis was examined. Degree of idiosyncratic messages communicated by retarded speakers was investigated in Study 2. Listening competence of retarded and adult listeners was compared in Study 3. Retarded subjects did consistently better on referential communication tasks requiring only sampling than on tasks requiring comparison or critical analysis. Referential communication messages provided by retarded speakers did not have greater meaning to themselves than to others. Finally, retarded listeners and adult listeners did not differ significantly in their ability to utilize the information given by retarded speakers. Implications of the findings for the study of the social communications of retarded children were discussed.

A comparison of two Spanish tests of receptive language

Twenty Spanish-speaking Mexican-American children were administered the receptive portion of the Screening Test of Spanish Grammar (STSG) and the Spanish version of the Test of Auditory Comprehension of Language (TACL). The correlation obtained between the two tests was not statistically significant. The correlation obtained between 24 syntactical items common to both tests was also not statistically significant. The probable reasons for the nonsignificant correlations obtained are discussed. In addition, a detailed critique of the Spanish version of the TACL is presented.