Ontogeny of humoral immunity in northern elephant seal (Mirounga angustirostris) neonates

OBJECTIVE: To assess relations of left ventricular (LV) geometry and function to insulin resistance in obesity-a condition associated with volume overload and abnormal LV relaxation. DESIGN: Cross-sectional relational study. SUBJECTS: 27 healthy overweight-obese subjects (18 women, body mass index (BMI) = 35.0+/-4.0 kg/m2) and 31 age-matched normal-weight controls (21 women, BMI = 22.6+/-2.4 kg/m2). MEASUREMENTS: Subjects were studied by Doppler-echocardiography the same day and hour (08.00 h) as measurements of fasting insulin and blood glucose were made. Insulin resistance was determined by the 'Homeostasis Assessment Model'. RESULTS: Twelve obese subjects with insulin resistance (IR) had higher body size than 15 patients without IR and higher blood pressure than normal-weight controls (all P < 0.01). Relative IR was related to isovolumic relaxation time. This relation was not maintained after controlling for age, blood pressure, weight and height. Isovolumic relaxation time was, however, positively related to diastolic blood pressure, a measure of load, in normal controls (r=0.44) and obese without IR (r=0.62) but not in insulin resistant subjects (r=0.14). CONCLUSION: IR does not independently influence myocardial relaxation in uncomplicated obesity, but modulates the effect of load on active diastole.     

Maternal factors as determinants of food intake during the suckling period

In experimental animals, three ways in which maternal factors may have an important influence on food intake are described. The first is the olfactory cues which attract the infant to the mother, and specifically to the nipple. The second is the volume of milk ingested, which may be primarily determined by milk availability rather than by the infant appetite (if appetite even exists in the infant). The third is the available evidence which suggests that it is the mother who plays the active role in the process of weaning. It is concluded that the possibility that these factors are also operative in the human mother-infant dyad has not been subjected to systematic investigation.     

Olfactory aversive conditioning in the newborn (3-hr-old) rat impairs later suckling for water and milk.

An olfactory conditioning paradigm tested whether newborn rats can acquire a conditioned aversion to olfactory events associated with their first postnatal meal 3-5 hr after birth. Exposure to lemon odor (conditioned stimulus [CS]) paired with intraoral infusions of 0.1% quinine (unconditioned stimulus) resulted in explicit conditioning. Responsiveness to a surrogate nipple providing water in the presence of the CS was significantly lower than the 3 control conditions. The conditioning dramatically suppressed responsiveness to a surrogate nipple providing milk, which normally is expressed voraciously in terms of sustained nipple attachment and milk intake. These findings suggest that as early as 3-5 hr after birth newborn rats are capable of aversive conditioning to odors in the context of suckling behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Intracellular calcium levels during the period of delayed excitotoxicity

Intracellular calcium concentrations ([Ca2+]i) among cultured hippocampal neurons were monitored during and in the hours following an excitotoxic glutamate application to determine the time course of changes involved in delayed excitotoxicity. After a 5 min toxic insult, [Ca2+]i increased immediately and remained elevated for an hour. Subsequently, [Ca2+]i declined to normal resting levels and remained so up to 13 hr following insult. Only a few neurons displayed greatly elevated [Ca2+]i at these extended times. Survival experiments in sister cultures indicated that 85% of the neurons died after 24 hr. Therefore, intracellular calcium returned to baseline levels prior to neuronal death. Additionally, during this period when basal calcium levels had recovered, the majority of neurons responded to a second excitatory amino acid application with a second increase in [Ca2+]i.     

Oral toxicity of bis(2-ethylhexyl) phthalate during pregnancy and suckling in the Long-Evans rat

Bis(2-ethylhexyl) phthalate (DEHP) is a compound widely used in plastics technology to impart flexibility to rigid polymers. We sought to determine whether the oral exposure of female rats to DEHP during gestation and suckling produces alterations in the litter. Female rats were exposed to different concentrations of DEHP suspended in drinking water (32.5 and 325 microl/litre) from day 1 of pregnancy to day 21 after delivery. Pup body weight gain and kidney, liver and testes weight was measured at different times (21, 28, 35, 42 and 56 days) after birth. Plasma concentrations of DEHP and histopathological alterations in kidneys, liver and testes were also studied. In addition, the ability of female pups (1 month of age) to perform a learned avoidance test, the 'beam walking' test, was evaluated. Perinatal exposure to DEHP produced no statistically significant changes in the body weight gain of offspring. Conversely, it produced a significant decrease in kidney and testes relative weight (organ/body weight) with a significant increase in relative liver weight. Signs of histological damage in kidneys, liver, and particularly testes, were observed. Pups exposed perinatally to the highest concentration of DEHP elicited a significant increase in the time necessary to perform the beam walking test.     

Leucocyte interleukin-1-like activity in the common seal (Phoca vitulina) and grey seal (Halichoerus grypus)

Interleukin-1 (IL-1) is an important cytokine with predominantly proinflammatory activities, which have been characterized in many mammals. This study showed the production of IL-1-like bioactivity by cultured seal leucocytes. Increasing concentrations of lipopolysaccharide (LPS) (0-1 micrograms/ml) stimulated an increase in measurable IL-1-like activity in cell culture supernates. This activity increased for the first 24 h after LPS stimulation and the substance responsible had an apparent molecular weight of 17 kDa on gel filtration, similar to that described for other species. Specificity of the bioassay used was confirmed by blocking the bioactivity with an IL-1 receptor antagonist (IL-1 ra).     

Serum enzyme activities in the African elephant (loxodonta africana)

The serum activities of aspartate aminotransferase, alanine aminotransferase, alpha-hydroxybutyrate dehydrogenase and creatine phosphokinase have been measured in the African elephant. In general, the values were broadly comparable with those of man except that alanine aminotransferase was much lower and creatine phosphokinase higher. No variation due to age, sex, season or location was observed.     

Changes in cervical fibronectin levels during pregnancy, labor and in the postpartum period

The authors analysed the fibronectin content of the uterine cervix during pregnancy and delivery. The aim of their investigation was furnishing data to the biochemical changes during cervical maturation. The ripening of the uterine cervix during pregnancy is a result of complicated interactions between different macromolecules, where the fibronectin plays a key role. The quantitative determination of the extracellular matrix fibronectin is impossible because its extraction from tissues recently is not solved. Taking this fact in consideration the authors choose a semiquantitative method, being reliable indicator of changes in fibronectin content of uterine cervix. They took small pieces of materials from portio vaginalis uteri of 139 women being in postmenopause and premenopause, in different stages of pregnancy and parturition concerning directly after delivery. The slides were incubated, with rabbit-anti-human fibronectin-FITC. The evaluation of fluorescence happened with an Axiophot (Zeiss) microscope. Authors stated that the fibronectin content in the cervical extracellular matrix and in the cellular membrane of fibroblasts increases during the 1st trimester pregnancy. This increase can be shown in the 3rd trimester as well and it drops significantly during delivery. They could not found any relationship between the leucocyte invasion observed during delivery and the changes of cervical fibronectin content. These observations call our attention to the importance of fibronectin in cervical ripening respectively dilatation and the need of further examinations.     

The maternal and fetal levels of human chorionic gonadotropin, human placental lactogen and prolactin during the perinatal period (author's transl)

The levels of human chorionic gonadotropin (HCG), human placental lactogen (human choriosomatomamotropin HCS) and prolactin (PRL) were determined in the serum of 72 maternity patients and the serum of the newborn infants. The determinations were done with radioimmunologic tests (RIA). These three protein hormones were also determined in the amniotic fluid and in the maternal serum from 4-6 days prior to the delivery of the infant. The concentration of HCG or HCS in the serum of the newborn infants was a mean 0.43 or 0.37% of the level in the maternal serum. The concentration of PRL in the serum of the newborn was 118% and slightly higher than in the serum of the mothers. The concentration in the amniotic fluid was 1.5% for HCG, 5.8% for HCS, and 252% for PRL, compared to the corresponding levels in the maternal serum. The fact that the hormone concentrations in the amniotic fluid are significantly higher than in the serum of the newborn suggests excretion of the hormones from the fetal circulation via the fetal liver and the fetal kidney. The high levels of PRL in the maternal and the newborn serum may be caused by the high concentrations of estrogen or progesterone. Increased during the course of the pregnancy there was a significant sex linked difference in the level of HCG in the maternal serum correlated to the sex of the newborn infant.     

Organochlorine and mercury residues in the harp seal (Pagophilus groenlandicus)

Samples of blubber, liver, kidney and brain, obtained from 10 male, 6 female neonatal, and 4 lactating female harp seals (Pagophilus groenlandicus), were analysed for DDT, dieldrin, PCB, and total mercury. Methyl mercury levels in blood were also determined. Biocide deposition was not significantly different in female and male ten day old pups. There were no significant differences in biocide levels in the liver of the 14/+ day old males, but in blubber there were significant differences in dieldrin and DDT. There was no clear relationship between biocide levels in the 6-18 year old lactating adults and their pups. Younger adult seals (6 and 7 years) were found to have higher levels of PCB and sigmaDDT levels in their blubber than did older females (10 and 18 years). Wide intraspecific variation was noted in organochlorine and mercury residue levels. Pups taken in 1973 were found to have lower organochlorine residues than pups taken in the same area in 1971. Preliminary investigation indicates that detectable amounts of organochlorine and mercury residues are capable of crossing the placenta in the harp seal.     

Geographic variations in the composition of ivory of the African elephant (Loxodonta africana)

OBJECTIVES: The purpose of the present study was to compare the inclination of the occlusal plane with occlusal guidance as a contributing factor to masticatory movement. METHODS: Masticatory movements of 41 young adults were measured using a 3-D mandibular movement analysing system. The inclination of the occlusal plane was measured in the sagittal plane using a 3-D digitizer. The contribution of the occlusal guidance and the inclination of the occlusal plane to the direction of the masticatory path of closure was evaluated at various closing levels. RESULTS: The masticatory path of closure outside the intercuspal range was influenced mainly by the inclination of the occlusal plane, and the masticatory path of closure near the intercuspal range was only influenced by occlusal guidance. The so-called gliding type masticatory pattern was observed predominantly in subjects with a posteriorly inclined occlusal plane. In contrast, a chopping type masticatory pattern was observed predominantly in subjects with an anteriorly inclined occlusal plane. CONCLUSIONS: The contribution of the inclination of the occlusal plane to masticatory movement was greater than that of occlusal guidance throughout the closing phase except near the intercuspal range.     

Calcium levels in maternal milk: relationships with calcium intake during the third trimester of pregnancy

Tumor necrosis factor-alpha (TNF-alpha) and nitric oxide (NO) exert a wide array of immunoregulatory, partly related effects. We examined the production of these two mediators by the human hairy cell leukemia cell line Eskol. Combined cell lysate and supernatant of Eskol cells (0.5 x 10(6) cells ml(-1)) incubated for 18 h, contained a mean of 1.5 ng ml(-1) TNF-alpha. This spontaneous TNF-alpha synthesis was enhanced by phorbol ester (PMA) and phytohemagglutinin (PHA) and decreased by dexamethasone. Nitrite, the stable product of NO, accumulated in the supernatant of Eskol cells after prolonged incubation. Maximal nitrite concentrations (range: 0.8-3.5 microM at 2 x 10(6) cells ml(-1)) were detected after 7 days of incubation. NO production was augmented by PHA and reduced by PMA. The inhibitors of NO synthase N(G)-monomethyl-L-arginine (L-NMMA) and aminoguanidine decreased NO synthesis. Simultaneous activation with the proinflammatory cytokines, interferon-gamma, interleukin-1beta and TNF-alpha, increased NO synthesis. These results suggest that NO production in Eskol cells results from inducible NO synthase activity. This is the first direct demonstration of NO formation in human lymphoid cells. The cell line, Eskol, may serve as a model to study regulation of TNF-alpha and NO synthesis in human B-cell leukemia.     

Immunoreactive growth hormone levels in pigs fed protein or energy restricted diets during the postweaning period

Developmental changes in growth hormone levels during protein or energy malnutrition was studied in weaned pigs. Three or 4 weeks old pigs from control dams were fed a control diet (18% protein), an energy-restricted diet (18% protein) or a low protein diet (6% protein) for 8 weeks. Energy restriction was achieved by feeding the control diet in amounts that allowed very little growth. After the restriction period, all pigs were fed the control diet ad libitum for another 8 weeks. Blood samples were collected at intervals throughout the experiment and the plasma was analyzed for growth hormone by radioimmunoassay. Post weaning protein deprivation resulted in higher growth hormone levels during the restriction period as compared to control pigs or pigs with a restricted energy intake.     

Cryptococcosis in tree shrews (Tupaia tana and Tupaia minor) and elephant shrews (Macroscelides proboscides)

OBJECTIVE: To determine the relation between metabolic and anthropometric parameters and circulating leptin concentrations in women with polycystic ovary syndrome (PCOS). DESIGN AND PATIENTS: Correlation of fasting serum leptin concentrations with anthropometric measures and multiple metabolic parameters including insulin and glucose responses to a 2-hour 75-g oral glucose tolerance test (OGTT) in 85 women with PCOS (17-36 years, body mass index (BMI) 29.9 +/- 0.9 kg/m2, mean +/- SD) and 18 control women (25-47 years, BMI 25 +/- 1.7 kg/m2). Diagnostic criteria for PCOS: characteristic ovarian morphology on ultrasound plus at least two of (1) elevated serum testosterone; (2) elevated serum androstenedione; and (3) reduced serum SHBG concentrations. MEASUREMENTS: Concentrations of androgens, lipids, PRL, gonadotrophins, and leptin were measured in the baseline fasting blood sample from an OGTT. Insulin and glucose were measured throughout OGTT. Serum leptin concentrations were measured by radioimmunoassay. RESULTS: Log leptin levels in the PCOS group correlated significantly with BMI (r = 0.85, P < 0.0001) and with 8 other parameters including waist/hip ratio (r = 0.51, P = 0.0005). By stepwise regression analysis, only BMI (P < 0.0001) and plasma high density lipoprotein concentration (P = 0.02) were independently correlated with log leptin levels, both positively. There was no effect of fat distribution, as measured by waist/ hip ratio, on leptin concentrations. Comparison of control subjects to a BMI-matched subgroup of 55 PCOS subjects revealed significantly higher circulating concentrations of LH, testosterone, DHEAS, progesterone and androstenedione, and higher glucose and insulin responses to OGTT in the PCOS group. Leptin levels were not different between the PCOS subgroup and control group (14.8 +/- 1.3 vs 12.1 +/- 2.3 micrograms/l, mean +/- SE, P = 0.26) and the relation of BMI to leptin levels determined by linear regression analysis also did not differ between the two groups. CONCLUSIONS: Our results indicate that circulating leptin concentrations in women with PCOS, a condition characterized by hyperandrogenaemia, increased LH concentrations and insulin resistance, are strongly related to BMI and not independently affected by circulating levels of insulin, gonadotrophins or sex hormones.     

The content of ascorbic acid in plasma and in 14 tissues of lambs of different ages during normal feeding and feeding restricted from time to time during the suckling period

In normally fed lambs (group 1) the content of ascorbic acid (AA) in the plasma on day 8, 18, 28, 38, 48, 60 and 100 after birth was the same as in lambs, that were fed on days 8 to 17 (group 2), 8 to 26 (group 3) and 8 to 35 (group 4) on the maintenance level. The restrictive feeding induced for a certain time a decrease in the glucose content of the plasma. In the lambs of group 2 and 3 there was no differences in the content of AA in 14 tissues compared to group 1. In the lambs of group 4 the body weight on the 35th day was only 54 and the mass of the hypophysis 60, of the lung 55.9, of the liver 51, of the heart 47.2, of the spleen 44.7 and of the kidney 38% of that of group 1; there was a tendency to a lower content of AA in most tissues. With increasing age the content of AA in the cerebrum, in the cerebellum, in the brain stem and in the testicles decreased; the highest content in the hypophysis was determined on day 180. The regulation of the synthesis of AA in the liver under normal and pathological conditions is discussed.     

Serum thyrotropin, prolactin, and growth hormone levels during the early neonatal period in the human infant

The purpose of this study was to evaluate the efficacy of a trapezoidal wave form for ventricular difibrillation. Overall efficacy showed the trapezoidal waveform to be effective for defibrillation, including patients weighing over 100 kg (220 lb). We concluded that (1) the trapezoidal waveform is an effective defibrillatory pulse and (2) the trapezoidal waveform offers pulse characteristics less deleterious than other established waveforms.     

Histogenesis of the chequered pattern of ivory of the African elephant (Loxodonta africana)

This study aimed to propose a hypothesis on the events which lead to the development of the characteristic chequered pattern of elephant ivory. Twenty fragments of ivory and six elephant tusks were obtained through the National Parks Board of South Africa. Polished surfaces were prepared in sagittal and longitudinal planes and the characteristics of the distinctive chequered pattern described. Light- and electron-microscopical techniques and image analyses were employed to determine the morphological basis of the pattern and to describe the spatial distribution, density and morphology of the dentinal tubules. These investigations showed that the distinctive pattern was the result of the sinusoidal, centripetal course followed by dentinal tubules. The apical, slanted part of the sinusoidal curve is the result of the centripetally moving odontoblast, which, during formation of ivory, progresses towards the centre of the tusk on a decreasing circumference. It is suggested that this leads to cell crowding, increased pressure between odontoblasts and subsequent apical movement of their cell bodies, cell degeneration and fusion. Odontoblastic degeneration and fusion probably relieve the pressure between the crowded odontoblasts by reducing their numbers and the remaining odontoblasts now orientate their centripetal course towards the tip of the tusk, thereby forming the anterior-directed part of the sinusoidal path of the tubule. As odontoblasts progress centripetally the diameter of the pulpal cavity decreases further and the processes of apical movement, fusion and degeneration of odontoblasts are repeated. This occurs until the pulpal cavity is obliterated.