An ENU-Induced Mutation of Nrg1 Causes Dilated Pupils and a Reduction in Muscarinic Receptors in the Sphincter Pupillae

BACKGROUND: N-ethyl-N-nitrosourea (ENU)-induced mutagenesis is a powerful tool for the study of gene function and the generation of human disease models. A large number of mouse mutants obtained by ENU-induced mutagenesis with a variety of phenotypes have been recovered. However, after genetic confirmation testing, only approximately 50% of the abnormal phenotypes were found to be heritable. METHODOLOGY/PRINCIPAL FINDINGS: A mouse mutant, Dp1, with a dilated pupil phenotype was induced with an N-ethyl-N-nitrosourea (ENU) mutagenesis strategy. Sequence analysis for Nrg1 reveals a G>A base substitution that flanks exon E59, encoding for an EGFβ domain, in the 5' splice donor site. The mutation affects but does not abolish the splicing of EGFβ-type Nrg1 mRNA in Dp1 mice and produces several different transcripts by activating other, cryptic splice sites. These types of protein isoforms are expected, and the result shows that, in the mutant, the effect is a decrease in but not an elimination of the high affinity EGFβ-type Nrg1 isoforms. This is partially compensated for by an increase in expression of the low affinity alpha forms or inactive proteins, suggesting that the mutation results in a hypomorphic allele. Interestingly, genetic model testing shows that Dp1 is a mutation that results in a dilated pupil phenotype that is inherited with very low penetrance when heterozygous and with complete penetrance when homozygous. Pharmacological and immunohistochemical tests show a reduction of muscarinic (M) receptors in the sphincter pupillae of Dp1 mice, which is a major cause of dilated pupils. CONCLUSIONS/SIGNIFICANCE: This study is the first report of an Nrg1 mutation being associated with a dilated pupil phenotype and the reduction of M receptors. This report may help in establishing more mutant mouse lines and models of human genetic disease and can be applied to other organisms. Dp1 mice are a valuable resource for the further clarification of Nrg1 biological function

Macrometastasis, Micrometastasis, and Isolated Tumor Cells in Sentinel Lymph Nodes of Early Breast Cancers: A 10-Year Histopathological and Survival Analysis of 537 Asian Patients.

© 2015 Société Internationale de Chirurgie. Background: In patients with negative sentinel lymph node biopsy (SLNB), axillary dissection (AD) can be avoided to reduce morbidities. However, there is only limited data on the rate of positive non-SLN (NSLN) in those who have micrometastasis and isolated tumor cells (ITC) in the literature. Methods: We did a retrospective review of all clinically node-negative breast cancer patients with SLNB done at our unit from January 2001 to June 2011. Multivariate analysis was adopted to evaluate the risk factors for NSLN metastasis. Difference in 5-year disease-free survival (DFS) was evaluated with log-rank test. Results: Five-hundred and thirty-seven patients underwent SLNB; 161 (30 %) had positive SLN on frozen section (FS), 50 of these patients (31 %) had NSLN metastasis, 25 patients had negative SLN on FS but were found to have micrometastasis on histopathology, and only 1 (4 %) of them had NSLN metastasis, while 14 patients were found to have ITC in SLN; none of them had NSLN metastasis. Multivariate analysis found that the number of SLN harboring micrometastasis is the only independent risk factor for NSLN metastasis in patients with micrometastasis (p value = 0.008). On the contrary; tumor size, grade, and biology were not associated with NSLN metastasis. 5-year DFS in patients with macrometastasis in SLN was 94.2 %, while that in patients with micrometastasis and ITC was 100 % (p value <0.001). Conclusion: NSLN metastasis in those who only have micrometastasis and ITC is rare, and 5-year DFS is significantly better in this group of patients as well. It is therefore a routine practice in our unit to omit AD in patients with micrometastasis and ITC on SLN.Link_to_subscribed_fulltex

Estudo citofotométrico da expressão dos marcadores tumorais Ki-67 e CD34 no adenocarcinoma de próstata

OBJETIVO: Quantificar a porcentagem da imunomarcação no índice de marcagem e densidade óptica do Ki-67 e CD34 no adenocarcinoma de próstata e compará-las entre si. MÉTODOS: Foram estudados, através de imunoistoquímica, o Ki-67 e o CD34 em 34 casos de adenocarcinoma de próstata provenientes de prostatectomia radical no período de 2000 a 2005 realizado no Hospital Regional do Gama em Brasília. Estes marcadores foram quantificados através do software SAMBA 4000 ® Sistema de Análise Microscópica de Busca Automática e do software IMMUNO® para análise das variáveis índice de marcagem e densidade óptica. Para avaliação da associação entre as expressões do marcador, foi estimado o coeficiente de correlação de Spearman. Para a comparação do tipo de lesão, foi usado o teste t de Student em amostras pareadas e não paramétrico de Wilcoxon. RESULTADOS: Dos 34 blocos que foram para leitura dos marcadores tumorais, 15 marcaram expressão com Ki-67, 34 com CD34 e 14 com ambos os marcadores. O índice de marcagem do CD34 teve valor mediano de 72,72%, valor mínimo 5,14% e valor máximo 88,81%. O índice de marcagem do Ki-67 teve mediana de 73,78%, mínimo de 16,87% e máximo de 87,47%. A densidade óptica do CD34 teve mediana de 48,33, mínimo de 35,65 e máximo de 85,86. Na densidade óptica do Ki-67 o valor da mediana foi 40,03 sendo a mínima de 21,53 e a máxima de 52,43. CONCLUSÃO: A expressão citofotométrica do Ki-67 teve índice médio de marcação de 64,04% e o CD34 de 61,64%. A expressão citofotométrica da densidade óptica média do Ki-67 foi de 39,49 e no CD34 de 53,69. Há diferença significativa entre a imunomarcação do Ki-67 e CD34 em relação à densidade óptica (p=0,025), não havendo diferença significativa no índice de marcagem (p=0,470)

The Private International Law of Access and Benefit-Sharing Contracts

This chapter considers the public—private international law interplay in the context of access and benefit-sharing (ABS) for genetic resources (GRs) and associated traditional knowledge (TK). The public international ABS framework, primarily via the Convention on Biological Diversity and its Nagoya Protocol, obliges contracting parties to ensure that access to GRs and TK is based on prior informed consent (PIC) and based on mutually agreed terms (MAT), and that benefits arising out of the utilization of GRs and TK are shared. This public law framework however leaves it to private ordering via ABS contracts between providers and users to determine nature and scope of benefit-sharing. And while the public law framework sets out a basic “enforcement” structure for ensuring that access is based on PIC and that MAT have been established, enforcing benefit-sharing commitments in ABS contracts is up to providers and users, relying on private law mechanisms. Because of the cross-border nature of most of the provider-user relations, enforcing ABS contracts raises complex questions on the jurisdiction of courts or arbitration tribunals, applicable law, and the enforcement of judgments or arbitral awards. This chapter reviews these private international law questions in light of the normative guidance the public international law ABS framework offers