Excision of breast fibroepithelial lesions: when is it still necessary?—A 10-year review of a regional centre

Breast Cancer Research and Treatment - Fibroepithelial lesions (FEL) range from benign fibroadenoma (FA) to malignant phyllodes tumor (PT), but can be difficult to diagnose on core needle biopsy...     

Synthesis and characterization of a novel magnetic porous carbon coated with poly(p-phenylenediamine) and its application for furfural preconcentration and determination in baby food and dry milk powder samples

The aim of the current research is to develop a MSPE method for the determination of furfural in baby food and dry milk samples. In this regard, a novel magnetic porous carbon composite coated with poly(p-phenylenediamine) was fabricated, characterized, and then applied to the preconcentration/extraction of furfurals from baby food and dry milk powder samples. Initially, magnetic nanoparticles (Fe₃O₄) were synthesized, and then coated with a metal–organic framework layer named MIL-101(Fe). Afterward, the magnetic MIL-101(Fe) was subjected to calcination under a nitrogen atmosphere and magnetic porous carbon was achieved. Finally, a layer of poly(p-phenylenediamine) was coated on the magnetic porous carbon. The structure of the nanocomposite was investigated with various methods, including FT-IR spectroscopy, electron microcopies (SEM and TEM), VSM, and XRD. The fabricated nanocomposite was applied in magnetic solid-phase extraction of furfural and hydroxymethyl furfural and their determination with liquid chromatography. The effect of experimental variables was explored by using an experimental design approach. The LODs and linear range for the target furfurals were 1.0–2.0 μg kg⁻¹ and 3.0–500 μg kg⁻¹, respectively. The method''s repeatability was explored using RSD values and was found to be in the range of 5.2–6.4% (one-day, n = 5) and 9.1–10.8% (day to day, n = 3). Eventually, this new method was employed for the extraction/quantification of target compounds in baby food and dry milk powder samples.

In this research, a novel magnetic porous carbon composite coated with poly(p-phenylenediamine) was fabricated, characterized, and then applied to the preconcentration/extraction of furfurals from baby food and dry milk powder samples.     

Effects of [Des-Tyr]-γ-endorphin and α-endorphin on substantia nigra self-stimulation

The β-lipotropin fragments, [des-Tyr¹]-γ-endorphin (DTγE, β-LPH_62–77) and α-endorphin (β-LPH_61–76) affect self-stimulating behavior associated with electrical stimulation of neurons of the ventral tegmentum area of rats in an opposite way. Subcutaneous administration of DTγE (5 and 25 μg) attenuated and that of α-endorphin (5 and 25 μg) facilitated this behavior. Similar opposite effects were observed after subcutaneous treatment with respectively the neuroleptic haloperidol (5 μg) and the psychostimulant amphetamine (100 μg). By using a biphasic testparadigm of decreasing and subsequent increasing the stimulating current intensity it was noted that the neuropeptides predominantly exerted their effect on responding at current intensities in the neighbourhood of the threshold for eliciting the behavior, whereas the neuroleptic and psychostimulant drug appeared to affect responding at currents associated with maximal performance as well. In contrast to haloperidol, the effectiveness of DTγE was of a long term nature, in that performance of the rat was still affected 24 hr after peptide treatment. The results support the hypothesis that DTγE in some aspects interacts with brain substrates in a way comparable to that of neuroleptics. The data further suggest that closely related fragments of β-lipotropin modulate on-going activity of in particular dopaminergic neuronal systems.     

Reduction of insulin binding in the arcuate nucleus of the rat hypothalamus after 6-hydroxydopamine treatment

Insulin receptors are present in the hypothalamus, but the cell types bearing them are unknown. In order to test the hypothesis that some insulin receptors in the hypothalamus are associated with catecholamine terminals, rats were injected with 50 μg or 75 μg doses (intracerebroventricular) of 6-hydroxydopamine (6-OHDA). Control rats received vehicle only. The animals were sacrificed 7 days after injection, and catecholamine and indolamine levels in the hypothalamus were measured by high performance liquid chromatography with electrochemical detection. Localization of specific binding sites for [¹²⁵I]-insulin in the arcuate (ARC), dorsomedial (DMN) and ventromedial (VMN) nuclei were determined by quantitative film autoradiography. Treatment with 6-OHDA resulted in a 70% reduction in hypothalamic norepinephrine content as compared to vehicle-treated controls (P < 0.01). A slight depletion of epinephrine, dopamine and indolamines was also detected. Computerized image analysis of the autoradiograms was used to determine radioactivity bound (DPM/mm²) in each nucleus. Highest binding was in the ARC and DMN, with much lower binding in the VMN. Insulin binding in the ARC of the 6-OHDA-treated group was decreased by 25% compared to controls (P < 0.01). No significant change in insulin binding was observed in the DMN or VMN. The 6-OHDA treatment had no significant effect on weight gain or on plasma insulin levels. The reduction of insulin binding in the ARC after 6-OHDA treatment supports the hypothesis that some insulin binding sites are located on catecholamine terminals in the arcuate nucleus.     

Interaction of a vasopressin antagonist with vasopressin receptors in the septum of the rat brain

The ability of d(CH2)5-Tyr(Me)-arginine-8-vasopressin, an antagonist of peripheral pressoric (V1-type) vasopressin receptors, to label vasopressin binding sites in the septum of the rat brain was evaluated. Using crude membrane preparations from the septum, 3H-arginine-8-vasopressin (AVP) specifically labels a single class of binding sites with a Kd of 2.9 nM and maximum binding site concentration of 19.8 fmole/mg protein. 3H-Antag also labels a single class of membrane sites but with higher affinity (Kd = 0.47 nM) and lower capacity (10.1 fmole/mg protein) than 3H-AVP. The rank order of potency of various competitor peptides for 3H-AVP and 3H-Antag binding was similar. Oxytocin was 100-1,000 fold less potent than AVP in competing for binding with both ligands. 3H-AVP and 3H-Antag showed similar labeling patterns when incubated with septal tissue slices. Unlabeled Antag also effectively antagonized vasopressin-stimulated phosphatidylinositol hydrolysis in septal tissue slices.     

Localization of binding sites for insulin-like growth factor-I (IGF-I) in the rat brain by quantitative autoradiography

In vitro quantitative autoradiography was used to localize IGF-I binding sites in rat brain. Slide-mounted sections of frozen rat brain were incubated in 0.01 nM ¹²⁵I[Thr⁵⁹]IGF-I, alone or mixed with 10 nM unlabeled [Thr⁵⁹]IGF-I or insulin, for 22 h at 4 °C and apposed to LKB Ultrofilm. Measurement of labeled [Thr⁵⁹]IGF-I binding by computer digital image analysis of the autoradiographic images indicated that high affinity IGF-I binding sites are widely distributed at discrete anatomical regions of the brain microarchitecture. The highest concentration of specific binding sites was in the choroid plexus of the lateral and third ventricles. Unlabeled porcine insulin was less potent than unlabeled IGF-I in competing for binding sites on brain slices. Regions of the olfactory, visual, and auditory, as well visceral and somatic sensory systems were labeled, in particular the glomerular layer of the olfactory bulb, the anterior olfactory nucleus, accessory olfactory bulb, primary olfactory cortex, lateral-dorsal geniculate, superior colliculus, medial geniculate, and the spinal trigeminal nucleus. High concentrations of IGF-I-specific binding sites were present throughout the thalamus and the hippocampus, (dentate gyrus, Ca1, Ca2, Ca3). The hypothalamus had moderate binding in the paraventricular, supraoptic, and suprachiasmatic nucleus. Highest binding in the hypothalamus was in the median eminence. The arcuate nucleus showed very low specific binding, approaching the levels found in optic chiasm and white matter regions. Layers II and VI of the cerebral cortex also had moderate IGF-I binding. The results suggest that the development and functions of brain sensory and neuroendocrine pathways may be regulated by IGF-I.