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Background Fine-needle aspiration biopsy (FNAB) is a minimally invasive, cost-effective diagnostic tool that can be used in low-resource settings. However, adequacy and accuracy of FNAB is highly dependent on the skills of the operator and requires specialized training. Poor technique can preclude definitive diagnoses because of insufficient quality or quantity of FNAB samples. We evaluated the efficacy of an intensive training experience in Tanzania on improving ultrasound-guided FNAB techniques. Methods A 2-day workshop offered didactic lectures, demonstrations, and hands-on practicum on fundamentals of ultrasound imaging and FNAB technique. A prospective interventional study design was used with pre- and postintervention surveys and assessments to measure the effect of the workshop on specific skills related to slide smearing and ultrasound-guidance among participants. Results Twenty-six pathologists and radiologists, including trainees in each specialty, participated in the workshop. Pre- and postworkshop assessments demonstrated that most participants improved significantly in nearly all technical skills for slide smearing and ultrasound-guided FNAB. After the workshop, most participants demonstrated substantial improvements in ability to prepare the ultrasound equipment, measure the lesion in three dimensions by ultrasound, target lesions in one pass using both parallel and perpendicular approaches, and prepare high-quality aspirate smears. Conclusion An in-country 2-day workshop in Tanzania was efficacious in transferring basic skills in FNAB smear preparation and ultrasound-guided FNAB, resulting in skills enhancement among participating pathologists and radiologists. Although mastery of skills was not the goal of this short workshop, participants demonstrated proficiency in most technical elements after workshop completion, and the workshop generated interest among select participants to pursue additional intensive training in cytopathology.

WOS: 000419766500013, PubMed ID: 28862261, Fibrolamellar carcinoma has a distinctive morphology and immunophenotype, including cytokeratin 7 and CD68 co-expression. Despite the distinct findings, accurate diagnosis of fibrolamellar carcinoma continues to be a challenge. Recently, fibrolamellar carcinomas were found to harbor a characteristic somatic gene fusion, DNAJB1-PRKACA. A break-apart fluorescence in situ hybridization (FISH) assay was designed to detect this fusion event and to examine its diagnostic performance in a large, multicenter, multinational study. Cases initially classified as fibrolamellar carcinoma based on histological features were reviewed from 124 patients. Upon central review, 104 of the 124 cases were classified histologically as typical of fibrolamellar carcinoma, 12 cases as 'possible fibrolamellar carcinoma' and 8 cases as 'unlikely to be fibrolamellar carcinoma'. PRKACA FISH was positive for rearrangement in 102 of 103 (99%) typical fibrolamellar carcinomas, 9 of 12 'possible fibrolamellar carcinomas' and 0 of 8 cases 'unlikely to be fibrolamellar carcinomas'. Within the morphologically typical group of fibrolamellar carcinomas, two tumors with unusual FISH patterns were also identified. Both cases had the fusion gene DNAJB1-PRKACA, but one also had amplification of the fusion gene and one had heterozygous deletion of the normal PRKACA locus. In addition, 88 conventional hepatocellular carcinomas were evaluated with PRKACA FISH and all were negative. These findings demonstrate that FISH for the PRKACA rearrangement is a clinically useful tool to confirm the diagnosis of fibrolamellar carcinoma, with high sensitivity and specificity. A diagnosis of fibrolamellar carcinoma is more accurate when based on morphology plus confirmatory testing than when based on morphology alone., NIDDK NIH HHSUnited States Department of Health & Human ServicesNational Institutes of Health (NIH) - USANIH National Institute of Diabetes & Digestive & Kidney Diseases (NIDDK) [P30 DK026743]

Brain-derived neurotrophic factor (BDNF) has been implicated in regulating adult neurogenesis in the subgranular zone (SGZ) of the dentate gyrus; however, the mechanism underlying this regulation remains unclear. In this study, we found thatBdnfmRNA localized to distal dendrites of dentate gyrus granule cells isolated from wild-type (WT) mice, but not fromBdnfklox/kloxmice where the long 3′ untranslated region (UTR) ofBdnfmRNA is truncated. KCl-induced membrane depolarization stimulated release of dendritic BDNF translated from long 3′ UTRBdnfmRNA in cultured hippocampal neurons, but not from short 3′ UTRBdnfmRNA.Bdnfklox/kloxmice exhibited reduced expression of glutamic acid decarboxylase 65 (a GABA synthase), increased proliferation of progenitor cells, and impaired differentiation and maturation of newborn neurons in the SGZ. These deficits in adult neurogenesis were rescued with administration of phenobarbital, an enhancer of GABAAreceptor activity. Furthermore, we observed similar neurogenesis deficits in mice where the receptor for BDNF, TrkB, was selectively abolished in parvalbumin (PV)-expressing GABAergic interneurons. Thus, our data suggest that locally synthesized BDNF in dendrites of granule cells promotes differentiation and maturation of progenitor cells in the SGZ by enhancing GABA release, at least in part, from PV-expressing GABAergic interneurons.

Mutations in the Bdnf gene, which produces transcripts with either short or long 3' untranslated regions (3' UTRs), cause human obesity; however, the precise role of brain-derived neurotrophic factor (BDNF) in the regulation of energy balance is unknown. Here we show the relationship between Bdnf mRNA with a long 3' UTR (long 3' UTR Bdnf mRNA), leptin, neuronal activation and body weight. We found that long 3' UTR Bdnf mRNA was enriched in the dendrites of hypothalamic neurons and that insulin and leptin could stimulate its translation in dendrites. Furthermore, mice harboring a truncated long Bdnf 3' UTR developed severe hyperphagic obesity, which was completely reversed by viral expression of long 3' UTR Bdnf mRNA in the hypothalamus. In these mice, the ability of leptin to activate hypothalamic neurons and inhibit food intake was compromised despite normal activation of leptin receptors. These results reveal a novel mechanism linking leptin action to BDNF expression during hypothalamic-mediated regulation of body weight, while also implicating dendritic protein synthesis in this process.

Accumulation of β-amyloid (Aβ) peptide and hyperphosphorylation of tau in the brain are pathological hallmarks of Alzheimer’s disease (AD). Agents altering these pathological events might modify clinical disease progression. NAP (Asn-Ala-Pro-Val-Ser-Ile-Pro-Gln) is an octapeptide that has shown neuroprotective effects in various in vitro and in vivo neurodegenerative models. Previous studies showed that NAP protected against Aβ-induced neurotoxicity, inhibited Aβ aggregation, and, by binding to tubulin, prevented disruption of microtubules. In this study, we investigated the effect of NAP on Aβ and tau pathology using a transgenic mouse model that recapitulates both aspects of AD. We administered NAP intranasally (0.5 μg/mouse per day, daily from Monday through Friday) for 3 mo, starting from 9 mo of age, which is a prepathological stage in these mice. NAP treatment significantly lowered levels of Aβ 1‐40 and 1‐42 in brain. In addition, NAP significantly reduced levels of hyperphosphorylated tau. Of particular interest, hyperphosphorylation at the threonine 231 site was reduced; phosphorylation at this site influences microtubule binding. Our results indicate that NAP treatment of transgenic mice initiated at an early stage reduced both Aβ and tau pathology, suggesting that NAP might be a potential therapeutic agent for AD. DOI 10.1385/JMN/31:02:165 Index Entries: Alzheimer’s disease; tau; phosphorylation; β-amyloid peptide; NAP; neuroprotection; intranasal administration; transgenic mouse; therapy.

Obesity and its sequelae constitute a major international healthcare problem. The obesity epidemic is due in part to higher calorie diets and reduced exercise over the past 30 years; however, increasing evidence has established genetic regulation of body weight as a major contributor to obesity. Brain-derived neurotrophic factor (BDNF) regulates development and plasticity of the central nervous system, and recent work has established a clear role for signaling through BDNF and its receptor TrkB in the control of body weight. Here we review research findings from animal models and human populations indicating that BDNF is a negative regulator of appetitive behavior and body weight.