Holocene sea ice variability driven by wind and polynya efficiency in the Ross Sea.

The causes of the recent increase in Antarctic sea ice extent, characterised by large regional contrasts and decadal variations, remain unclear. In the Ross Sea, where such a sea ice increase is reported, 50% of the sea ice is produced within wind-sustained latent-heat polynyas. Combining information from marine diatom records and sea salt sodium and water isotope ice core records, we here document contrasting patterns in sea ice variations between coastal and open sea areas in Western Ross Sea over the current interglacial period. Since about 3600 years before present, an increase in the efficiency of regional latent-heat polynyas resulted in more coastal sea ice, while sea ice extent decreased overall. These past changes coincide with remarkable optima or minima in the abundances of penguins, silverfish and seal remains, confirming the high sensitivity of marine ecosystems to environmental and especially coastal sea ice conditions.

[Serologic diagnosis of streptococcal diseases. Ulterior data on the comparison of 2 methods (streptozyme and antistreptolysin O]. / In tema di diagnostica sierologica delle malattie streptococciche. Ulteriori dati sul confronto tra due metodologie (Streptozyme e ASLO).

Increasingly thorough analysis of the antigen structures of Group A beta-haemolytic streptococci has revealed the presence of antigen components with differentiated immune responses in relation to common streptococcal conditions. It is therefore extremely useful in laboratory practice to have a multiple antigen that reveals the immune response to a streptococcal infection so that we can study the serological behaviour of individual streptococcal pictures with their complications and sequelae. Research conducted to date indicates that the streptozyme test can explore the five main streptococcal isoenzymes both for rapid screening and for the quantification of the degree of antibody response. This is confirmed by the results obtained by numerous Authors over the past 15 years, results that demonstrate the high sensitivity of STZ (Streptozyme) at antibody level that single antibody reactions are apparently not capable of revealing. The polyvalent antigen represented by STZ seems to be the best tool for the demonstration of responses to the individual isoenzymes of the very numerous streptococcal strains in circulation (Group A, C and G beta-haemolytics). The possibility of using microtiter techniques for serum assays is also emphasised. These techniques have given repeatable results and are also easy to read.

[Microbiological, kinetic and clinical study on a new cephamycin: cefotetan]. / Ricerca microbiologica, cinetica e clinica su una nuova cefamicina: cefotetan.

Microbiological, kinetic and clinical studies were conducted on a new cephamycin, cephotetan. In vitro the antibiotic was found to be very effective against all strains tested. It had a particularly strong action against Gram negative bacteria too. Kinetically speaking, an intravenous bolus produced a high plasmatic concentration with a half life of about 4 hours. Elimination via the kidneys was fastest in the first 3 hours after administration (49.82%) and the slowed down. 82.76% of the dose administered was excreted within 24 hours. This antibiotics is particularly indicated in cases of urinary, respiratory and biliary infections.

Effect of cyclosporin A on the T-effector and T-suppressor cell response in contact sensitivity.

The effect of cyclosporin A (CyA) on the induction, expression and regulation of the immune response to the contact sensitivity agent 2,4-dinitroflouro-benzene, (DNFB) has been studied in BALB/c mice. CyA was administered orally during the sensitization phase or during the elicitation phase. The following results were obtained. CyA administered orally during the sensitization phase at a high dose resulted in a reduction of the contact sensitivity response. Feeding lower doses had no effect on the ear swelling response. CyA inhibited the ear swelling response if administered during the elicitation phase. In transfer experiments it was shown that the induction of the T-effector cell of delayed hypersensitivity (TDH) was insensitive to the suppressive action of CyA, while the effector function of this T-cell subpopulation was CyA-sensitive. T-suppressor (TS) cell response was studied in animals by inducing tolerance through epicutaneous application of an allergen overload and by transfer of TS cells induced by intravenous injection of the contact sensitizer. Tolerance induction in vivo and TS-cell induction and function were inhibited in CyA-treated animals.

The water jet-guided Nd:YAG laser in the treatment of gastroduodenal ulcer with a visible vessel. A randomized controlled and prospective study.

In a randomized, prospective study, 57 patients with a gastroduodenal ulcer and a visible vessel with or without spurting bleeding were treated with a Nd:YAG laser (lambda = 1.064 nm). Twenty-eight of these patients were treated using the conventional non-contact (NC) modality, and 29 were treated with the water jet (WJ) laser. Apart from the technical advantages (minimal smoke development, no damage to adjacent structures) the WJ group had a lower rate of induced spurting bleeds (25% WJ versus 55% NC). The therapeutic failure/mortality rate of 7%/0% respectively for the water-jet group was lower than the 18%/7% for the non-contact group. The initial clinical results of this study suggest that the water-jet Nd:YAG laser system is superior to the non-contact system.