instruction:
In this task, you're given a paragraph from the research paper and your task is to generate a suitable title for the research paper based on the given paper. Under 100 words is a good title length.
question:
Bovine renal brush-border membrane vesicle aminopeptidase N at various stages of purity was treated with two bifunctional cross-linking agents. A pattern of emergence of higher molecular weight forms was observed. By using a cleavable cross-linker, aminopeptidase N was shown to cross-link both to itself and to its breakdown products as well as to dipeptidyl peptidase IV. Using this technique it was possible to identify three of the breakdown products as 45 kDa, 66 kDa and 95 kDa peptides. N-terminal amino acid sequence analysis was used to define the precise cleavage points for the bovine renal aminopeptidase N breakdown products. The short amino acid sequences obtained show strong sequence similarity with the human intestinal and rat kidney aminopeptidase N.
answer:
The oligomeric structure of renal aminopeptidase N from bovine brush-border membrane vesicles


question:
Redirecting the splicing machinery through the hybridization of high affinity, RNase H-incompetent oligonucleotide analogs such as phosphoramidate morpholino oligonucleotides (PMO) might lead to important clinical applications. Chemical conjugation of PMO to arginine-rich cell penetrating peptides (CPP) such as (R-Ahx-R) 4 (with Ahx standing for 6-aminohexanoic acid) leads to sequencespecific splicing correction in the absence of endosomolytic agents in cell culture at variance with most conventional CPPs. Importantly, (R-Ahx-R) 4 -PMO conjugates are effective in mouse models of various viral infections and Duchenne muscular dystrophy. Unfortunately, active doses in some applications might be close to cytotoxic ones thus presenting challenge for systemic administration of the conjugates in those clinical settings. Structureactivity relationship studies have thus been undertaken to unravel CPP structural features important for the efficient nuclear delivery of the conjugated PMO and limiting steps in their internalization pathway. Affinity for heparin (taken as a model heparan sulfate), hydrophobicity, cellular uptake, intracellular distribution and splicing correction have been monitored. Spacing between the charges, hydrophobicity of the linker between the Arg-groups and Arg-stereochemistry influence splicing correction efficiency. A significant correlation between splicing correction efficiency, affinity for heparin and ability to destabilize model synthetic vesicles has been observed but no correlation with cellular uptake has been found. Efforts will have to focus on endosomal escape since it appears to remain the limiting factor for the delivery of these splice-redirecting ON analogs.
answer:
Delivery of steric block morpholino oligomers by (R-X-R) 4 peptides: structure-activity studies


question:
LETTERS that the quantitative assessment of the effectiveness of public health intervention measures for SARS is a difficult task for modelers. To make models useful for assessing the effects of specific intervention measures and for predicting the future dynamics during an ongoing epidemic, we need improved knowledge on the transmission mechanisms, pathogenesis, and the epidemiologic determinants of the spread of the virus. Any retrospective analysis of the 2003 SARS epidemic that improves our knowledge of SARS epidemiology is welcome.
answer:

SARS epi-demiology and cumulative case curve