Pituitary gland height evaluated with magnetic resonance imaging in premature twins: the impact of growth and sex.

BACKGROUND: Pituitary gland height reflects secretory activity of the hypothalamo-pituitary axis. OBJECTIVE: To assess the cumulative impact of fetal growth and sex on pituitary gland height in premature twins, dissociated from prematurity. MATERIALS AND METHODS: A retrospective study was conducted, assessing the pituitary gland height in 63 pairs of preterm twins, measured from T1-weighted magnetic resonance imaging (MRI). Auxological parameters, including body weight, body length, and head circumference, at birth and at the time of MRI, were used as proxies for fetal and postnatal growth, respectively. The study population was divided into two groups, using corrected age at around term equivalent as the cutoff point. Statistical analysis was performed using mixed-effects linear regression models. RESULTS: When pituitary gland height was evaluated at around term equivalent, a greater pituitary gland height, suggesting a more immature hypothamo-pituitary axis, was associated with the twin exhibiting lower auxological data at birth. The same association was observed when body weight and length at MRI were used as covariants. In the group evaluated after term equivalent, a smaller pituitary gland height, suggesting a more mature hypothamo-pituitary axis, was associated with male sex. This difference was observed in twin pairs with higher average body weight at birth, and in babies exhibiting higher auxological data at MRI. CONCLUSION: After isolating the effect of prematurity, at around term equivalent, pituitary gland height reflects the cumulative impact of fetal growth on the hypothalamo-pituitary axis. Subsequently, pituitary gland height shows effects of sex and of fetal and postnatal growth.

The contribution of metabolic parameters of FDG PET/CT prior and during therapy of adult patients with lymphomas.

Lymphomas are the most common hematological malignancies and are further distinguished in Hodgkin lymphoma (HL) and non-Hodgkin (NHL). For staging purposes and for assessing response to treatment, the Lugano classification is currently used, both for HL and NHL patients, whereas for the assessment of prognosis, several prognostic systems exist, such as the international prognostic index (IPI) and revised-IPI for diffuse large B cell lymphomas, follicular lymphoma IPI (FLIPI)-1 and 2 for follicular lymphomas, and the international prognostic score for advanced HL. The aim of this systematic review was to determine the significance of the metabolic FDG PET/CT parameters, such as metabolic tumor volume (MTV) and total lesion glycolysis (TLG), in monitoring therapeutic interventions and prognostic outcome of patients with HL and NHL. We performed a systematic search on the literature and selection of articles concerning treatment evaluation, response and survival in association with MTV and TLG in patients with lymphomas. Our review documented that in most studies, baseline MTV and TLG were predictive of treatment response, progression-free survival (PFS) and overall survival (OS) for both HL and NHL patients. There were conflicting results for the value of interim determination of MTV and TLG. Our conclusion was that combination of baseline MTV and TLG parameters with prognostic scoring systems, such as IPI, or FLIPI-1 and -2, will add additional predictive power for response and prognosis in lymphoma patients.

Effects of Cupressus sempervirens cone extract on lipid parameters in Wistar rats.

BACKGROUND: Lipid-lowering drugs have been developed to treat hyperlipidemia, but they are expensive, while serious side-effects may occasionally occur. In Albania, a hydroalcoholic extract of the cones of Cupressus sempervirens is used to treat a variety of disorders, including hyperlipidemia. The purpose of our study was to assess the effects of Cupressus sempervirens cone extract (CSE) on the lipid profile of Wistar rats. MATERIALS AND METHODS: The animals were divided into two groups. Group I (30 animals) served as a control group. Serum lipid parameters, muscle and liver enzymes, red and white blood count, platelets, and serum concentrations of uric acid and creatinine were determined at baseline and at weeks 6, 12, 18 and 24 of the study. RESULTS: The oral administration of the extract resulted in a substantial decrease of serum total cholesterol, which was significant even after 6 weeks of treatment. Moreover, these animals exhibited lower total cholesterol levels compared to the controls after the initiation of treatment (p < 0.001) during the study period. The administration of the extract led to a substantial reduction in serum triglycerides (p < 0.05) in Group I, comparing 0 week to 6-24 weeks. However no significant differences in triglyceride levels were observed between CSE animals (Group I) and controls (Group II) during the entire study period. No significant changes in HDL-cholesterol in the other parameters occurred in either group. CONCLUSION: The administration of CSE has an important lipid-lowering effect in Wistar rats.

Magnetization transfer imaging of the pituitary gland.

Magnetization transfer (MT) techniques provide tissue contrast which depends mainly on the concentration of macromolecules. The magnetization transfer phenomenon is determined by the restricted macromolecular protons and is quantified by the magnetization transfer ratio (MTR). Since many macromolecular structures are implicated in the secretory activity of the pituitary gland, this imaging technique has recently been used for the study of the normal adenohypophysis and the pre-operative and post-operative evaluation of pituitary adenomas. Significant changes of the MTR with age occur in normal subjects. In patients with hyperprolactinemia, the MTR of prolactin-secreting tumors is higher and that of the non secreting adenomas is lower compared to the MTR values of the normal pituitary gland of age and sex matched controls. In some patients operated on for growth hormone adenomas, although classic MR images were negative for residual tumor, increased MTR values were highly suggestive of persistence of adenoma tissue, in agreement with biochemical findings of persisting secretory activity. These data suggest that MT techniques might be an additional useful tool in the assessment of pituitary gland disorders.

MRI of the hypothalamic-pituitary axis in children.

In childhood, the MR characteristics of the normal pituitary gland are well established. During the first 2 months of life the adenohypophysis demonstrates high signal. Pituitary gland height (PGH) decreases during the 1st year of life and then increases, reaching a plateau after puberty. The magnetization transfer ratio (MTR) increases in both sexes up to the age of 20 years. On dynamic contrast-enhanced studies, the posterior pituitary lobe enhances simultaneously with the straight sinus, and the adenohypophysis later, but within 30 s. In genetically determined dysfunctional states, the adenohypophysis may be normal, hypoplastic, or enlarged. Pituitary enlargement, observed in Prop 1 gene mutations, is characterized by a mass interposed between the anterior and posterior lobes. An ectopic posterior lobe (EPP), associated with a hypoplastic or absent pituitary stalk, may be observed in patients with hypopituitarism. Tumors of the hypothalamic-pituitary (HP) axis may be the origin of adenohypophyseal deficiencies. A small hypo-intense adenohypophysis is found in iron overload states and is often associated with hypogonadotrophic hypogonadism. Absence of the posterior lobe bright signal, with or without a thick pituitary stalk or a mass at any site from the median eminence to the posterior pituitary lobe, may be found in diabetes insipidus. Hydrocephalus, suprasellar arachnoid cysts, hypothalamic hamartomas and craniopharyngiomas may result in central precocious puberty (CPP). Increased PGH in girls with idiopathic CPP is useful for its differential diagnosis from premature thelarche (PT). Pituitary adenomas, observed mainly in adolescents, present the same MR characteristics as those in adults.