Revision of the Antarctic and sub-Antarctic species of the family Stegocephalidae (Crustacea: Amphipoda) with description of two new species

The Antarctic and sub-Antarctic elements of the family Stegocephalidae DANA, 1855 (Crustacea: Amphipoda) are revised, and a key to the species is presented. Two new species are described: Andaniexis ollii n.sp. and Phippsiella watlingi n.sp. The family is represented in the Southern Ocean by 19 species belonging to 11 genera, of which one is reported as new to the area

Multiplex sorting of foodborne pathogens by on-chip free-flow magnetophoresis

This study reports multiplex sorting of Salmonella typhimurium and Escherichia coli 0157, from broth cultures and from pathogen-spiked skinned chicken breast enrichment broths by employing microfluidic free-flow magnetophoresis. Magnetic beads of different sizes and magnetite content, namely Dynabeads anti-salmonella and Hyglos-Streptavidin beads together with the corresponding pathogen-specific biotinylated recombinant phages, were utilised as affinity solid phases for the capture and concentration of viable S. typhimurium and E. coli 0157. Following optimisation, the protocol was used to demonstrate continuous magnetophoretic sorting of the two pathogen-bound magnetic bead populations from mixed cultures and from pathogen-spiked chicken pre-enrichment broths under the influence of a Halbach magnet array. For example, in the la tter case, a pure population of S. typhimurium-bound Dynabeads (72% recovery) was sorted from a 100 μL mixture containing E. coli 0157-bound Hyglos beads (67% recovery) within 1.2 min in the presence of 0.1% Tween 20. This proof-of-principle study demonstrates how more than one pathogen type can be simultaneously isolated/enriched from a single food pre-enrichment broth (e.g. Universal food enrichment broth)

On-chip acoustophoretic isolation of microflora including S. typhimurium from raw chicken, beef and blood samples

Pathogen analysis in food samples routinely involves lengthy growth-based pre-enrichment and selective enrichment of food matrices to increase the ratio of pathogen to background flora. Similarly, for blood culture analysis, pathogens must be isolated and enriched from large excess of blood cells to allow further analysis. Conventional techniques of centrifugation and filtration are cumbersome, suffer from low sample throughput, are not readily amenable to automation and carry a risk of damaging biological samples. We report on-chip acoustophoresis as a pre-analytical technique for the resolution of total microbial flora from food and blood samples. The resulting ‘clarified’ sample is expected to increase the performance of downstream systems for the specific detection of the pathogens. A microfluidic chip with three inlets, a central separation channel and three outlets was utilized. Samples were introduced through the side inlets, buffer through the central inlet. Upon ultrasound actuation, large debris particles (10–100 μm) from meat samples were continuously partitioned into the central buffer channel, leaving the “clarified” outer sample streams containing both, the pathogenic cells and the background flora (ca. 1 μm) to be collected over a 30 min operation cycle before further analysis. The system was successfully tested with Salmonella typhimurium-spiked (ca. 103 CFU mL⁻¹) samples of chicken and minced beef, demonstrating a high level of the pathogen recovery (60–90%). When applied to S. typhimurium contaminated blood samples (107 CFU mL⁻¹), acoustophoresis resulted in a high depletion of the red blood cells (99.8%) which partitioned in the buffer stream, whilst sufficient numbers of the viable S. typhimurium remained in the outer channels for further analysis. These results indicate that the technology may provide a generic approach for pre-analytical sample preparation prior to integrated and automated downstream detection of bacterial pathogens

Resonant Raman Scattering by quadrupolar vibrations of Ni-Ag Core-shell Nanoparticles

Low-frequency Raman scattering experiments have been performed on thin films consisting of nickel-silver composite nanoparticles embedded in alumina matrix. It is observed that the Raman scattering by the quadrupolar modes, strongly enhanced when the light excitation is resonant with the surface dipolar excitation, is mainly governed by the silver electron contribution to the plasmon excitation. The Raman results are in agreement with a core-shell structure of the nanoparticles, the silver shell being loosely bonded to the nickel core.Comment: 3 figures. To be published in Phys. Rev.

Successful pregnancies in women on renal replacement therapy: Report from the EDTA Registry

This study reports the geographical incidence of successful pregnancies in women on renal replacement therapy (RRT) and related information on gestation and clinical status of newborns. The impact of successful pregnancy on graft function was assessed by means of a retrospective case-control study. Since 1977 special questionnaires have been sent to each dialysis and transplant centre which reported babies born to mothers on RRT on the yearly centre questionnaire. After 10 years of data collection, a total of 490 pregnancies and 500 babies were available for analysis. A percentage of 88.4 of the babies were born to mothers with a functioning graft, 11.2% to mothers on chronic haemodialysis, and the remaining 0.4% to mothers on CAPD. Almost 50% of all successful pregnancies werereported from the UK. The number of successful pregnancies increased steadily and in parallel with the increasing number of females of childbearing age with a functioning renal transplant. The majority of mothers delivered at age 24-32. For transplanted mothers delivery occurred most commonly during the 3rd and 4th year after successful transplantation. In approximately 85% of cases the duration of pregnancy was shorter than the lower 10th percentile of normal. Birthweight was reduced in accordance with gestational age. Newborn mortality was 1.8%. Fifty-three mothers with a successful pregnancy in 1984-1987 were computer matched with controls according to a number of criteria. The serum creatinine concentration recorded in coded form at the end of each year on the individual EDTA patient questionnaire was used to assess changes in graft function. In 94% of these cases the serum creatinine, recorded 0-11 months before delivery, did not exceed 160 umol/1. Graft function deteriorated in 18% ofmothers as compared to 24% of controls. Twentyfour to 36 months postpartum, changes of serum creatinine were similar in test cases and controls, suggesting that a successful pregnancy does not adversely affect graft function if this was stable and well preserved at the time of conceptio

Rehabilitation of young adults during renal replacement therapy in Europe: The presence of disabilities

The aim of this study was to analyse rehabilitation during RRT in 617 young adults from different European countries who started dialysis or transplantation before the age of 15 years. The data were derived from the EDTA Registry patient data files and a special questionnaire that was sent to centres reporting to the EDTA Registry. The duration of RRT was more than 10 years in 63% of patients. Fifty-four percent were living with a functioning graft and 46% were on dialysis. The prevalence and severity of motor, hearing, sight, and mental disabilities were analysed retrospectively. They were found to vary according to primary renal disease and method oftreatment. One-third of patients had one or more disabilities at the start of RRT. Although disability status had changed in many patients by 31 December 1986, some disability remained in one-third of the patients available for study. Disabilities were recorded as mild in the majority of patients. Both improvement and worsening of motor and mental disability occurred more often than changes of hearing capacity and sight. It is concluded that prevention and treatment of disabilities need special attention in children and young adults on RRT in order to improve rehabilitatio

Rehabilitation of young adults during renal replacement therapy in Europe: 2. Schooling, employment, and social situation

The educational status, employment rate and social situation were studied in 617 patients between 21 and 35 years of age who started renal replacement therapy (RRT) as children. The data were derived from a special questionnaire concerning disability and rehabilitation sent to dialysis and transplant centres reporting to the EDTA Registry. Fifty-six percent of patients completed secondary school and one in three went on to vocational training. Eleven percent of patients attended university, and 16% were reported to have gone to a special school for the handicapped. Up to one-third of patients who attended different school types failed to complete their education. There were notable geographical differences in schooling and in employment. Fifty-six percent of all patients were employed. Lack of schooling was considered to be a major reason for unemployment. Sixty-one percent of patients with disabilities and 34% without disabilities were receiving invalidity payments. The place of residence of these patients aged 21-35 was usually the parental home. Compared to the general population of similar age, only a few patients were married (13.5% of the total study group) and 8% had children. In summary, the present report shows that the major factors influencing rehabilitation on RRT are the presence of disabilities, the method of treatment, geographical factors, duration of RRT, and the underlying primary renal diseas

Demography of Dialysis and Transplantation in Europe, 1984: Report from the European Dialysis and Transplant Association Registry

The demography of treatment of children by renal replacement therapy in Europe is presented based on returns of individual patient questionnaires to the EDTA Registry up until the close of 1984. Patient questionnaires for 1984 were completed by all centres which defined themselves as special paediatric units. A total of 4983 patients have been reported to the Registry up until 31 December 1984 as having commenced renal replacement therapy under the age of 15. Of these, 1570 were known to be alive on a defined form of treatment at the end of 1984 and still under the age of 15. The numbers of these patients kept alive by different forms of treatment in individual countries are presented. The stock of patients aged under 15 at the end of 1984 exceeded 30 per million child population in Belgium, France, Iceland and Luxembourg. The highest age specific acceptance rates for children onto renal replacement therapy during 1984 were noted in those aged between 10 and 14 at first treatment. Age specific acceptance rates for children varied greatly between individual countries, and 18 countries reported no new patients under the age of 5 during 1984. Transplant activity in paediatric patients during 1984 has been analysed and results on regrafting presented. Proportional distribution of primary renal diseases amongst children commencing therapy in 1984 is shown according to age at start of treatment. Haemolytic uraemic syndrome was reported as the cause of end-stage renal failure in 12.0% of children commencing treatment under the age of 5, and 12.3% of children between 5 and 9. Finally, information on cause of death in paediatric patients dying during 1984 is presented, and shows cardiovascular disease was the leading cause of mortalit