Sample carryover and cleaning procedures for asymmetrical flow field-flow fractionation instrument.

Asymmetrical flow field-flow (AF4) fractionation aims in separation of sample components to yield elution of homogenous fractions identified as well-defined peaks in the chromatograms. Separation that occurs in matrix-free open channel potentiates high recovery that can be close to 100%. However, sample properties and separation conditions may induce carryover of sample components during AF4 analysis and in sample sequences. This compromises the quality of the data collected from the online detectors and the downstream offline analytics of the collected fractions. In this study, we followed sample carryover in AF4 using model viruses and analyzed various cleaning solutions and rinse methods to reduce carryover. We introduce an SDS-NaOH -based rinsing and decontamination protocol for the AF4 instrument enabling high-quality data collection.

Outcomes of growing rod surgery for severe compared with moderate early-onset scoliosis: a matched comparative study.

Aims: The aim of this study was to compare the outcomes of surgery using growing rods in patients with severe versus moderate early-onset scoliosis (EOS). Patients and Methods: A review of a multicentre EOS database identified 107 children with severe EOS (major curve ≥ 90°) treated with growing rods before the age of ten years with a minimum follow-up of two years and three or more lengthening procedures. From the same database, 107 matched controls with moderate EOS were identified. Results: The mean preoperative major curve was 101° (90 to 139) in the severe group and 67° (33° to 88°) in the moderate group (p < 0.001), which was corrected at final follow-up to 57° (10° to 96°) in the severe group and 40° (3° to 85°) in the moderate group (p < 0.001). T1-S1 height increased by a mean of 54 mm (-8 to 131) in the severe group and 27 mm (-4 to 131) in the moderate group at the initial surgery (p < 0.001), and by 50 mm (-17 to 200) and 54 mm (-11 to 212), respectively, during distraction (p = 0.84). The mean number of complications per patient was 2.6 (0 to 14) in the severe group and 1.9 (0 to 10) in the moderate group (p = 0.040). Five patients (4.7%) in the severe group and three (2.8%) in the moderate group developed a neurological deficit postoperatively (p = 0.47). Conclusion: Severe EOS can be treated effectively using growing rods, but the risk of complications is high. Cite this article: Bone Joint J 2018;100-B:772-9.

Membrane-containing virus particles exhibit the mechanics of a composite material for genome protection.

The protection of the viral genome during extracellular transport is an absolute requirement for virus survival and replication. In addition to the almost universal proteinaceous capsids, certain viruses add a membrane layer that encloses their double-stranded (ds) DNA genome within the protein shell. Using the membrane-containing enterobacterial virus PRD1 as a prototype, and a combination of nanoindentation assays by atomic force microscopy and finite element modelling, we show that PRD1 provides a greater stability against mechanical stress than that achieved by the majority of dsDNA icosahedral viruses that lack a membrane. We propose that the combination of a stiff and brittle proteinaceous shell coupled with a soft and compliant membrane vesicle yields a tough composite nanomaterial well-suited to protect the viral DNA during extracellular transport.

Relationship between occupation and lung cancer as analyzed by age and histologic type.

The information on occupations obtained in Finland's 1970 census was linked with the files of the Finnish Cancer Registry from 1971 through 1980 in order to establish the occupational group-specific relative risks (RR) of lung cancer. The distribution of lung cancers into histologic types varied with the age of the patients at the time of diagnosis. When 38 high-risk occupational groups were combined, the age-specific distribution of lung cancer into histologic types did not differ significantly from the corresponding distribution for other economically active men. Of individual occupational groups, young farmers had a higher RR of small cell carcinoma than older farmers or other economically active young men. Besides their high overall lung cancer risk, miners and quarriers had a very high risk of small cell carcinoma as compared with other economically active men. Servicemen and repairmen in the metal industry had a high risk of epidermoid carcinoma. Welders had a high risk of epidermoid carcinoma, but their risk of small cell carcinoma was lower than expected. There were no other excess risks of any histologic type of lung cancer attributable to occupational factors.