Trimester-specific reference intervals for thyroid function parameters in pregnant Caucasian women using Roche platforms: a prospective study.

BACKGROUND: Standard thyroid function parameters reference intervals (RI) are unsuitable during pregnancy, potentially resulting in incongruous treatments that may cause adverse effects on pregnancy outcomes. We aimed at defining trimester-specific TSH, FT4 and FT3 RI, using samples longitudinally collected from healthy Caucasian women. MATERIALS AND METHODS: Blood samples from 150 healthy Caucasian women, who had a physiological gestation and a healthy newborn at term, were collected in each trimester and at around six months post-partum. They showed mild iodine deficiency. After excluding women with overt TSH abnormalities (> 10 mU/L) and/or TPO antibodies, data from 139 pregnant women were analyzed by means of widely used Roche platforms, and TSH, FT4 and FT3 trimester-specific RI were calculated. Post-partum data were available for 55 subjects. RESULTS: Serum TSH RI were 0.34-3.81 mU/L in the first trimester, and changed slightly to 0.68-4.07 U/L and 0.63-4.00 mU/L in the second and third trimester, respectively. Conversely, both FT4 and FT3 concentrations progressively decreased during pregnancy, the median values in the third trimester being 14.8% and 13.2% lower, respectively, than in the first trimester. Thyroid function parameters in the first trimester were similar to those measured after the end of pregnancy. CONCLUSIONS: This study calculates trimester-specific RI for thyroid function parameters in pregnancy, and proposes the reference limits that should be adopted when using Roche platforms in Caucasian women.

Biochemical responses and accumulation of cadmium in Spirodela polyrhiza.

The present study focused on biochemical responses of Spirodela polyrhiza to cadmium stresses and its accumulation. The laboratory experiments were conducted for the assessment of biochemical responses and accumulation of cadmium in plants at its various concentrations (0.1, 0.5, 1.5 and 2.0 ppm) at the regular interval for twelve days exposure. Spirodela showed visible symptoms like withering of roots and chlorosis at higher concentration (2.0 ppm), however the plant showed normal growth at lower concentration (0.1 ppm). The estimation of biochemical parameters (total chlorophyll, protein and carbohydrate) of test plants showed a significant increase at lower concentration (0.1 ppm) of cadmium. The biochemical changes decrease with increase in exposure concentration and duration. The toxic effect of cadmium is directly proportional to its concentration and duration. The accumulation of cadmium by Spirodela polyrhiza was maximum at four days exposure duration and gradually decreases.