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OBJECTIVE To assess performance of Nucleus 22 mini system pediatric users converted from the Spectra 22 body-worn to the ESPrit 22 ear-level speech processor using aided thresholds and speech discrimination measures before and after the conversion. STUDY DESIGN Spectra 22 body-worn speech processor users were chosen using preselection criteria (stable map, ability to report on the quality of the signal, no device problems). The subjects underwent tuning, map conversion, fitting of the ESPrit 22, and aided soundfield threshold and speech discrimination testing. SUBJECTS The first 100 consecutive conversions are analyzed in this study. Fifty children (50%) were female, and 50 (50%) were male. The average age at implantation was 4.6 years (median 4.3 years, range 1.7 to 11 years). The average age of fitting the ear level speech processor was 11.1 years (median 11 years, range 6.2 to 18.2 years). SETTING Tertiary referral pediatric cochlear implant center in the United Kingdom. RESULTS Of the 100 fittings attempted, all Spectra 22 maps could to be converted for use in the ESPrit 22. Of these 100 fittings, 44 were straightforward with no adjustment to map parameters being required, and 56 needed rate reductions and other map adjustments to achieve the conversion. The difference of the mean thresholds before and after the conversion did not exceed 2 dB across the frequencies studied (0.5-4 kHz). In 95% of the cases, the differences were less than 9 dB(A). With regard to speech discrimination testing, the mean threshold before the conversion was 53.4 dB and after the conversion 52.7 dB. Of the 100 conversions, only five children stopped using the ESPrit 22 despite fitting being achieved. CONCLUSION Conversion from the Spectra 22 body worn to the ESPrit 22 ear level speech processor was found to be feasible in all the 100 cases studied. Only a minority (5%) of children chose not to use the ear level speech processor suggesting that children and parents were satisfied from the conversion.

South Africa is an important supplier of stone fruit to the northern hemisphere in the months of November to March. The voyage by sea to the main markets in the UK and Continental Europe necessitates production of cultivars that are able to maintain an acceptable eating quality for a period of at least four weeks from the time of harvest. Four Japanese plum (Prunus salicina) cultivars were examined with the view to extend their storage life under regular atmosphere (RA) conditions at -0.5°C following either RA or controlled atmosphere (CA) shipping, using either the commercial dual temperature (-0.5°C, 7.5°C, -0.5°C) or a single high temperature (7.5°C) regime. The cultivars included the locally bred 'Sapphire', 'Songold' and 'Laetitia' as well as 'Angeleno' which is well known in plum producing countries internationally. Storage life of all four cultivars could be extended for an additional two to three weeks under RA conditions at -0.5°C without adverse effects on quality, provided that CA was applied during the shipping phase, either under the dual or single high temperature regimes. Fruit firmness was best retained under CA (dual temperature) conditions. These fruit also showed the lowest respiration rates, ethylene production rates and internal ethylene content. Skin colour development was better under single high than under dual temperature conditions, and also better under RA than CA shipping.

‘Songold’ plums (Prunus salicina Lindl.) were harvested at optimum and post-optimum maturity with a flesh firmness of 64 and 44 N, respectively. After cold storage for 10 days at −0.5 °C, followed by 18 days at 7.2 °C, the plums were ripened for 14 days at 10 °C. The fruit was analysed for soluble solids, internal conductivity, pectic composition and viscosity of water soluble pectin at eight examination stages during storage and ripening. Insoluble pectin levels declined during cold storage and ripening while soluble pectin levels increased to make up the difference. Neither harvest maturity nor storage time had a significant effect on the concentration of calcium pectate, and this pectic fraction did not appear to influence development of gel breakdown (GB). Water soluble pectin and availability of cell fluids, as indicated by viscosity and internal conductivity, respectively, indicated a high gel potential in plums of both maturities, but at different stages during storage and ripening. Significant levels of GB developed only in plums harvested at post-optimum maturity. In this fruit, significantly higher sugar levels and loss of cell membrane integrity early in storage probably enhanced formation of pectin-sugar gels as cell fluids bind with pectins in cell walls.

SummaryPlums (Prunus salicina cv. Songold) were cold stored according to a single-temperature regime comprising 28 d at −0.5°C, and a dual-temperature regime comprising 10 d at −0.5°C followed by 18 d at 7.2°C. After cold storage, the plums were ripened for 8 d at 10°C. Pectolytic enzyme activity, pectic composition, internal conductivity and gel breakdown were determined at seven stages during storage and ripening. Although not exposed to chilling temperatures prior to harvest, approximately 10% of the plums exhibited gel breakdown at harvest, indicating that the disorder cannot be classified solely as a cold-storage chilling disorder. The higher temperatures of the dual-temperature regime resulted in higher polygalacturonase activity than with the single-temperature fruit. Consequently, protopectin degradation and the concomitant production of water- soluble pectins were greater in the dual-temperature fruit. Single-temperature storage resulted in higher pectinmethylesterase activity during the latter s...

Plums ( Prunus salicina cultivar ‘Songold’) were harvested on three dates, 7 days apart, from top and bottom sectors of trees trained on a palmette system. Fruit maturity at harvest, assessed in terms of skin ground colour, flesh firmness, soluble solids, titratable malic acid and soluble solids to acid ratio, was significantly affected by harvest date and canopy position. Delayed harvest was associated with advanced maturity, and, within trees, bottom fruit were more mature than top fruit. Similarly, these parameters measured after storage at −0.5°C for 10 days, followed by 18 days at 7.2°C and 7 days at 10°C, indicated that fruit quality was also affected by harvest date and canopy position. Other quality indices affected were gel breakdown, overripeness and decay. Best overall fruit quality was obtained in earlier harvested fruit with a ground colour of 2.6 as measured with an apple colour meter and a flesh firmness of 5.2 kg. More mature fruit developed the most gel breakdown, and in fruit harvested last, concentrations of N, P, K, Ca and Mg were lower than in earlier harvested fruit, and were least optimal for good fruit quality. Susceptibility to post-harvest decay was also highest in fruit harvested at the later date.

Plums (Prunus salicina cv. Songold) were cold stored for 10 d at -0.5°C followed by 18 d at 7.2°C and 7 d at 10°C. On the day of harvest and after 15,30 and 35 d of storage, the physiology, anatomy and development of internal disorders in inner and outer mesocarp tissue were assessed. Soluble solids, juice pH, internal conductivity, viscosity of soluble pectin and membrane leakage were significantly higher in the inner tissue, while titratable malic acid levels were lower, indicating that fruit was riper on the inside than the outside. Changes as indicated by the same variates showed that the rate of ripening in inner tissue was more rapid than in the outer mesocarp tissue over storage time. Gel breakdown in inner tissue was associated with high viscosities of water soluble pectin, permeable membranes, and as a result, binding of cell fluids which led to low levels of extractable juice. In outer tissue where extractable juice levels were higher, overripeness developed. At the ultrastructural level, it was...

Plums (Prunus salicina cv. Songold) were stored at -0.5°C for up to 50 d. On the day of harvest and thereafter at ten-day intervals, sub-samples were stored at 15°C and allowed to ripen for eight d...

Ultrastructure et recherche biochimique des changements se produisant au niveau des lipides, acides amines libres et sucres sur l'embryon et le gametophyte femelle de semence 24 semaines apres fecondation

Summary Cytokinin-like activity which co-chromatographed with zeatin, ribosylzeatin and glucosylzeatin was detected in the epimatium, female gametophyte and embryo sporophyte of germinating Podocarpus henkelii seeds. The level of endogenous cytokinins increased markedly in the embryo sporophyte prior to the onset of radicle elongation. From the results it can be concluded that the endogenous cytokinins play an important role in the germination process. They are apparently involved in those reactions which stimulate radicle elongation, particularly as these cytokinins disappear immediately after the radicle starts to elongate. As bound cytokinins do not increase at this time it would appear that the cytokinins are metabolised and/or utilized rapidly in the metabolically active embryo.

The transfer of tumour-specific cytotoxicity against a murine fibrosar-coma has been demonstrated in vitro using xenogeneic RNA extracted from tumour-cell-immune animals. Poly(A)-tailed messenger RNA from immunogenic RNA was isolated by passage through an oligo(dT)-cellulose column, and evaluated to determine whether the same tumour-specific cytotoxicity could be transferred. Aliquots of normal C3H mouse lymphocytes were treated with poly(A)-containing immune RNA, whole-cell immune RNA lacking poly(A) and total cellular immune RNA. Treated cells were tested in vitro using an adaptation of the Takasugi and Klein microcytotoxicity assay. Percent cytotoxicity was calculted using cells treated with fractions of normal RNA as control. An increase in tumour cytotoxicity was found with poly(A)-containing immune RNA. The optimum dose of poly(A)-tailed immune RNA was estimated as 6.5 microgram of RNA per 4 x 10(6) lymphocytes. Populations of lymphocytes were separated using glass and nylon wool. T- and B-enriched populations were treated with various RNA components. The adherent cell population showed no significant cytotoxicity, whilst treatment of the nonadherent population with poly(A)-tailed immune RNA produced high levels of cytotoxicity.

The role of mineral nutrition in the development of internal breakdown of plums was evaluated by applying various statistical models to data obtained in a field survey. All techniques cont...

Etude ultrastructurale et biochimique sur l'embryon et le gametophyte femelle des semences de Podocarpus henkelii neuf jours apres scarification et incubation sur un milieu humide

Cellular immunity directed against polyoma virus-induced antigen was observed with C3H/HeJ splenic lymphoid cells from mice sensitized by a short-term immunization schedule with syngeneic polyoma 4198 and 4198V tumor cells. Polyoma specificity of the response was shown by demonstration that splenic cells from DBA/2J animals with polyoma virus-induced tumors were cytotoxic for the C3H 4198 and 4198V cells, but not for the L-M cell, another cell line of C3H origin. The polyoma-specific response in the syngeneic system was detectable with the dye exclusion assay but not with the colony inhibition procedure. Colony inhibition with the L-M cell was observed with sensitized lymphoid cells in both allogeneic and syngeneic systems.

Characteristic morphological abnormalities were found to be present on lymphocytes from patients with advanced solid tumours. Numerous microprojections were characteristically present on human peripheral blood lymphocytes from cancer patients while non-cancer subject control lymphocytes ('normal' lymphocytes) appeared significantly smoother. Incubation of normal lymphocytes in cancer serum resulted in increased occurrence of these microprojections whereas incubation of normal cells in normal heterologous serum resulted in no apparent surface changes. Incubation of cancer lymphocytes in levamisole, an immunostimulant, did not abrogate surface projections.

Corynebacterium parvum, a Gram-positive anaerobic bacillus thought to be a strong immunological stimulant, has been shown to decrease tumour growth and prolong survival in patients with metastatic disease. Study of the effect of a single injection of a strain of C. parvum (CN. 6134) in six patients with stage IV metastatic breast cancer is reported. Results of laboratory tests to judge the physical and immunological effects of the drug infusion 24 hr post-treatment and weekly thereafter for 3 weeks are evaluated. Within 24 hr after C. parvum administration, most patients experienced fever and nausea. Blood counts and differential counts exhibited increased values 24 hr after treatment with a strong shift to the left. Lymphocyte and monocyte counts were greatly depressed at 24 hr. T-cell numbers in peripheral blood did not appear to be altered, but the picture with regard to B cells was less clear. Normal count was recovered by day 8. It appears that intravenous administration of C. parvum produces a temporary marked immunological depression which returns to essentially normal values in 8 days. The return to normal may be accompanied by resolution of the endotoxin-like syndrome of side-effects. Further study of patients receiving this therapeutic agent is important to detect enhancement of the anti-tumour immunological response precipitated.

Cellular immunity directed against polyoma virus-induced antigen was observed with C3H/HeJ splenic lymphoid cells from mice sensitized by a short-term immunization schedule with syngeneic polyoma 4198 and 4198V tumor cells. Polyoma specificity of the response was shown by demonstration that splenic cells from DBA/2J animals with polyoma virus-induced tumors were cytotoxic for the C3H 4198 and 4198V cells, but not for the L-M cell, another cell line of C3H origin. The polyoma-specific response in the syngeneic system was detectable with the dye exclusion assay but not with the colony inhibition procedure. Colony inhibition with the L-M cell was observed with sensitized lymphoid cells in both allogeneic and syngeneic systems.

An aqueous two-phase polymer system was used to isolate plasma membranes from a palpable mouse fibrosarcoma. The excised tumor tissue was washed with sterile saline and pushed through nylon screens of decreasing mesh size. This cell suspension was placed in Tris-buffered, isotonic sucrose plus MgSo4 and homogenized by nitrogen cavitation. A pellet was collected from the homogenate by low-speed centrifugation and was added to the aqueous two-phase polymer system. After several brief, low-speed centrifugations, the interfacial material between the polymer phases was collected. Data from enzyme and biochemical assays demonstrated that this fraction was plasma membrane. This method provided a high yield of the surface membrane in less than three hours.

Agglutination of Rh(O)(D) erythrocytes by specific antiserum was inhibited by crude and crystalline N-acetylneuraminic acid, less inhibited by its glycoyl derivative, and weakly inhibited by its degradation product, N-acetyl-mannosamine, and by D-mannose. A brain ganglioside containing neuraminic acid and a Pseudomonas polysaccharide were even more inhibitory. Inhibition was specific for anti-D sera.

With the avalanche of information concerning nucleic acids currently accumulating from many scientific disciplines, a more complete knowledge of the biological role of nucleic acids is evolving simultaneously. As immunologists, it is necessary to consider that any given animal host is actually a complete and functioning ecological unit of specialized cells, all of which were derived from one fertilized ovum. As yet, we are still uncertain as to what particular cells function as immunocompetent cells in maintaining the integrity of the animal in a continually changing environment. All somatic cells of a given individual in interphase supposedly contain the same genetic material (DNA) of which only a small portion is involved or “turned on” in the transcription of messenger RNA (Frenster, 1965). It is tempting to speculate that the “turning-on” and “turning-off” of genes might well be one physiological function of the host’s immune system. With this perspective, we wish to present a portion of our research experience in the immunization of experimental animals with mammalian and bacterial ribosomes.

After the synthesis of arsphenamine by Ehrlich and Bertheim 1 and its successful introduction by Ehrlich and Hata 2 in the therapy of spirillosis and by Wechselmann 3 and Uhlenhuth and Mulzer 4 in the treatment of syphilis, a considerable attempt has been made to ascertain the mode of action of the arsphenamines. Ehrlich and Hata 2 stated that arsphenamine exerted no direct action in the test tube on spirochetes of relapsing fever. Plaut, 5 Truffi and Sabbia 6 and Bronfenbrenner and Noguchi 7 were not able to kill Spirochaeta pallida in the test tube with high concentrations of arsphenamine. Ehrlich and Bertheim 1 assumed that the active principle was a product of the breaking down of arsphenamine, the "arsenoxide." Voegtlin and Smith 8 produced convincing evidence that the action of the various arsphenamines depends on their conversion into one type, the trivalent oxides with the structure R-AsO, and