A rapid method for plasma ammonia estimation using an indigenously purified enzyme

Determination of ammonia level in blood is important, especially in the diagnosis of hepatic disorders. An indigenously purified enzyme was used in the standardisation of the assay. The assay is a two reagent system, requires five minutes for completion and can be performed at temperature between 25–27°C. Performance of the assay was assessed by linearity, imprecision, functional sensitivity and interference studies. Lyophilised reagent I and reagent II were found stable for at least one year. The plasma level of ammonia for the controls was 13.7±7.3 μMol/L, whereas for subjects of hepatic disorders, it was 69.1±32.4 μMol/L (P<0.001). The functional sensitivity was between 2–1000 μMol/L. Within-run coefficient of variation was between 1.1–2.0% and between-run coefficient of variation was between 1.9–3.7%. The mean recovery after dilution was 99.6%. The present method can estimate ammonia up to 1000 μMol/L without dilution of sample. Assay time of five minute may be shortened to one minute. This method is suited for routine clinical use in treatment of hepatic disorders.     

Effects of short-term hormone replacement on atherogenic indices in Indian postmenopausal women

Indian ethnicity by itself is a strong risk factor for development of CAD in Indian postmenopausal women due to lower HDL levels as compared to Whites and women of oriental origin. We evaluated and compared the short-term effects of menopause, estrogen replacement therapy and combined estrogen and progestin replacement therapy on various atherogenic indices. 40 postmenopausal women, both surgical and natural (20 each) were selected. 10 surgical postmenopausal women were given 0.625 mg conjugated estrogens daily for 6 months and 10 natural postmenopausal women were given 0.625 mg conjugated estrogen with 2.5 mg medroxyprogesterone acetate daily. 20 women were included in the control group and given placebo. Fasting venous blood samples were analyzed for extended lipid profile and calculated atherogenic indices before starting the therapy and after 1,3 and 6 months. LDL and Apolipoprotein B increased (p<0.05) and those of Apolipoprotein A1 and HDL decreased in the control groups. In both the study groups levels of serum cholesterol and LDL decreased (p<0.05) and those of HDL and Apolipoprotein A1 increased (p<0.01). LDL/HDL, Apo B/ApoA1, Total Cholesterol/HDL decreased significantly (p<0.05) in both the study groups compared to the control groups. The effect of estrogen alone was more significant as compared to combination therapy. Log Triglycerides (TG)/HDL ratio showed a decrease in women on estrogen alone but the difference was not significant. Our study confirms that short term HRT has a favorable effect on atherogenic indices in Indian postmenopausal women.     

A Microarray Immunoassay for Serum Thyrotropin and Thyroglobulin Using Antibodies Immobilized on Track-Etched Membranes

Serum thyroglobulin (Tg) and thyroid stimulating hormone (TSH) measurements have evolved as important analytes for monitoring the prognosis of patients with differentiated thyroid cancer, post-thyroidectomy. Individual analyte immunoassay is the current practice in clinical pathology, but the simultaneous assay for all relevant analytes for a given disease, can reduce assay costs, improve patient compliance and give the clinician more information for an unequivocal diagnosis. Microarray immunoassay (MI) can achieve this goal and, hence, we have developed and validated a immuno-radiometric MI for quantitation of serum TSH and Tg by using highly micro-porous polycarbonate (PC) track-etched membranes (TEM) to immobilize the monoclonal anti-TSH and polyclonal anti-Tg antibodies in ~1 mm diameter spots. Non-competitive immunoassays were performed using mixture of ¹²⁵I labeled monoclonal anti-TSH and anti-Tg antibodies. Phosphorimager was used to quantify the bound radioactivity. TSH and Tg were detected with detection limit of 0.07 µIU/ml and 0.13 ng/ml respectively, which is lower than the clinically required cut-off level. The assay showed: acceptable intra-assay precision within 20 % and recovery in the range of 76–111.2 %. MI compared well with the established immunoradiometric assay (IRMA) with r = 0.98, p < 0.01 (n = 41). No cross-reactivity was seen between the immobilized antibodies. Although two hormones are addressed in this report, MI using PC TEM and isotopic/non-isotopic tracers has the potential for highly automated multiplexed analysis.     

Adrenocortical activity and the Brazelton Neonatal Assessment Scale: moderating effects of the newborn's biomedical status

The Brazelton Neonatal Behavioral Assessment Scale with Kansas Supplement (NBAS-K) was administered midway between feedings to 60 newborns who were between 32 and 122 hours old. 35 of the newborns were classified as extremely healthy and normal (Subgroup I), whereas 25 (Subgroup II) were characterized by slight perinatal problems including gestational age 36-37 weeks or 42+ weeks, and fetal distress during labor. All of the newborns were healthy enough to be cared for in a healthy newborn, Level I nursery. Immediately following administration of the NBAS-K, a blood sample was obtained for plasma cortisol determination. Correlations between behavioral responding on the NBAS-K and levels of plasma cortisol revealed few significant relations for the sample as a whole. When the 2 subgroups were examined separately, a number of significant relations emerged. Newborns in Subgroup I who were more competent in their motor control and state regulation capacities as assessed by Lester's Cluster Scores for the NBAS-K exhibited higher levels of plasma cortisol. In contrast, newborns in Subgroup II who exhibited a greater adrenocortical response to the examination showed more behaviors indicative of high behavioral arousal and distress. This pattern of relations for Subgroup II appeared to be mediated by the number of hours that had elapsed since delivery. As postpartum time increased, the strength of the association between adrenocortical activity and behavioral arousal/distress decreased for Subgroup II. A systems theory approach is used to interpret the difference in patterns of correlations found for the 2 subgroups.     

Adverse childhood experiences and hallucinations

OBJECTIVE: Little information is available about the contribution of multiple adverse childhood experiences (ACEs) to the likelihood of reporting hallucinations. We used data from the ACE study to assess this relationship. METHODS: We conducted a survey about childhood abuse and household dysfunction while growing up, with questions about health behaviors and outcomes in adulthood, which was completed by 17,337 adult HMO members in order to assess the independent relationship of 8 adverse childhood experiences and the total number of ACEs (ACE score) to experiencing hallucinations. We used logistic regression to assess the relationship of the ACE score to self-reported hallucinations. RESULTS: We found a statistically significant and graded relationship between histories of childhood trauma and histories of hallucinations that was independent of a history of substance abuse. Compared to persons with 0 ACEs, those with 7 or more ACEs had a five-fold increase in the risk of reporting hallucinations. CONCLUSION: These findings suggest that a history of childhood trauma should be looked for among persons with a history of hallucinations.     

Psychobiological studies of stress and coping: an introduction

Developmental psychobiology is the study of how the interplay between behavioral and physiological processes supports and directs development. This symposium section is devoted to work in this interdisciplinary domain focused on examining stress and how young organisms cope with and are affected by stressful experiences. In this introduction to the symposium section, the problems of interpreting and integrating information on stress reactivity derived from a combination of behavioral and physiological measures are discussed.