Use of 1alpha-OH cholecalciferol in preventing post parturient hypocalcaemia and its potential value for the prevention of milk fever in dairy cows

Cows which received 250 mug 1alpha-hydroxy cholecalciferol (1alpha-OH D3) intramuscularly within two hours after calving suffered significantly less post-parturinet hypocalcaemia and hypophosphataemia than control cows. There was a small depression in plasma magnesium concentrations in the treated cows. 1alpha-OH D3 shows potential for the prevention or treatment of milk fever.     

Stress-induced gonadotropin and prolactin secretory patterns

To further evaluate the influence that sex, time of day and/or stage of the estrous cycle have on stress-induced changes in gonadotropin secretory patterns, rats were subjected to acute ether stress and subsequently sacrificed at 1.5, 3, 5, 10 and 15-min intervals. A significant change in FSH levels was not detectable, however serum LH levels consistently showed a transient elevation, and prolactin release occurred rapidly and in large increments in every case. Variation in basal hormone levels due to sex, circadian rhythmicity, or estrous cyclicity did not alter the pattern of the response of individual hormones to the stress but did markedly influence the magnitude of the response.     

An interactional approach to dysfunctional silencing in family therapy

This paper presents an interactional approach to the problem of dysfunctional silencing in family therapy. Silencing is classified as dysfunctional if it satisfies two conditions: (a) it occurs repeatedly and independently of content, and (b) it functions as negative feedback that limits change in the family system. Dysfunctional silencing is defined as those efforts of one or more family members to limit change by repeatedly blocking the communication of another family member, who in turn colludes by tacitly agreeing to remain silent. The interactional approach presented utilizes conflict-resolution techniques and videotape feedback; it is illustrated by a case example.     

Ventilation, gas exchange and metabolic scaling of a sea turtle

A new dichromic interference filter was used as the excitation filter in colour and black-and-white fluorescein angiography of the human fundus. The interference filter transmits light shorter than 490 nm (blue) and longer than 640 nm (red). In colour photography the red light shows the topography of the fundus. In black-and-white photography, the red light is prevented from reaching the fundus by an additional absorption filter used together with the interference filter. These two comprise the excitation filter, which eliminates the pseudo-fluorescence from black-and-white angiograms.     

Estimating enthalpy of vaporization from vapor pressure using Trouton's rule

The enthalpy of vaporization of liquids and subcooled liquids at 298 K (delta H(VAP)) is an important parameter in environmental fate assessments that consider spatial and temporal variability in environmental conditions. It has been shown that delta H(VAP)P for non-hydrogen-bonding substances can be estimated from vapor pressure at 298 K (P(L)) using an empirically derived linear relationship. Here, we demonstrate that the relationship between delta H(VAP)and PL is consistent with Trouton's rule and the ClausiusClapeyron equation under the assumption that delta H(VAP) is linearly dependent on temperature between 298 K and the boiling point temperature. Our interpretation based on Trouton's rule substantiates the empirical relationship between delta H(VAP) degree and P(L) degrees for non-hydrogen-bonding chemicals with subcooled liquid vapor pressures ranging over 15 orders of magnitude. We apply the relationship between delta H(VAP) degrees and P(L) degrees to evaluate data reported in literature reviews for several important classes of semivolatile environmental contaminants, including polycyclic aromatic hydrocarbons, chlorobenzenes, polychlorinated biphenyls and polychlorinated dibenzo-dioxins and -furans and illustrate the temperature dependence of results from a multimedia model presented as a partitioning map. The uncertainty associated with estimating delta H(VAP)degrees from P(L) degrees using this relationship is acceptable for most environmental fate modeling of non-hydrogen-bonding semivolatile organic chemicals.     

Dietary calcium decreases blood pressure without decreasing renal vascular resistance or altering the response to NO blockade

Many vasoactive elements are involved in the elevation of blood pressure in spontaneously hypertensive rats (SHR). Elevated dietary calcium has been observed to reduce blood pressure in SHR. This study investigates interactions among dietary calcium, renal vascular resistance (RVR), elevation of blood pressure and effects of norepinephrine and nitric oxide synthesis. We completed a series of experiments on two groups each (fed low, 0.1% and high, 2.0% dietary calcium, respectively) of 9-week-old Wistar Kyoto (WKY), 9-week-old and 6-week-old SHR. Although 9-week-old SHR had elevated baseline blood pressure compared to 9-week-old WKY and also compared to 6 week-old SHR, there was no corresponding elevation in baseline RVR. All SHR fed high calcium diets had lower blood pressure compared to low calcium diets, and there was no corresponding reduction in RVR. WKY controls' blood pressure and RVR were unaffected by dietary calcium levels. In all hypertensive rats the blood pressure and renal vascular resistance were elevated by N(G)-nitro-L-arginine methylester (L-NAME), but the dietary differences were sustained. Blood pressure of WKY was unaffected by the low dose of L-NAME. The increase in RVR to L-NAME was greater in SHR than in controls. The renal vascular response to norepinephrine was related to diet in older SHR, but smaller and unrelated to diet in younger SHR. Following L-NAME, WKY had greater responses to norepinephrine than 9-week-old SHR. We conclude that noradrenergic vasoconstriction is enhanced in the adult SHR, especially in the absence of high calcium diet. Alterations in NO synthesis may effect the norepinephrine response.     

Purification and Use of Glycomacropeptide for Nutritional Management of Phenylketonuria

ABSTRACT:  Individuals with phenylketonuria (PKU) cannot metabolize phenylalanine (Phe) and must adhere to a low-Phe diet in which most dietary protein is provided by a Phe-free amino acid formula. Glycomacropeptide (GMP) is the only naturally occurring protein that does not contain Phe, and is of interest as a source of protein for dietary management of PKU. However, commercially available GMP contains too much Phe from residual whey proteins and does not contain adequate levels of all the indispensable amino acids to provide a nutritionally complete protein. The aim of this study was to increase purity of GMP and develop a mass balance calculation for indispensable amino acid supplementation of GMP foods. Cation exchange chromatography, ultrafiltration/diafiltration, and lyophilization were used at the pilot plant scale to decrease Phe. Enough purified GMP (5 kg) was manufactured to provide 15 PKU subjects with a 4-d diet in which the majority of protein was from GMP foods. A mass balance was used to supplement GMP foods so that all indispensable amino acids met or exceeded the daily recommended intake. GMP foods were tested in a human clinical trial as a replacement for the traditional amino acid formula. Nutritionally complete GMP foods created with high purity GMP provide individuals with PKU with more options to manage PKU, which may lead to improved compliance and quality of life.