Caseous Lymphadenitis Caused by Corynebacterium pseudotuberculosis in Alpine Chamois (Rupicapra r. rupicapra): a Review of 98 Cases.

Corynebacterium pseudotuberculosis is the causative agent of caseous lymphadenitis (CLA) in domestic and wild ruminants. Here we describe CLA in alpine chamois (Rupicapra r. rupicapra) based on a series of 98 cases of C. pseudotuberculosis infection confirmed by bacteriology and gene sequence analysis. The population included 53 males and 45 females distributed within three age groups: up to 18 months (n = 14), 18 months to 4 years (n = 11) and over 4 years (n = 73). Four different gross lesion distribution patterns, observed individually or variably combined in the same animal, were defined: (1) cutaneous/external (i.e. subcutaneous lymph nodes with or without muscle involvement, n = 34); (2) abdominal visceral (i.e. only abdominal organs involved: liver and/or spleen and/or kidney and/or lymph nodes, n = 35); (3) thoracic visceral (i.e. only thoracic organs involved: lung and/or heart and/or lymph nodes, n = 26); and (4) generalized visceral (i.e. abdominal and thoracic organs involved, n = 26). In six particularly severe cases, mammary gland, testis, vertebral bone and the central nervous system were also affected. Macroscopically, most abscesses were characterized by fluid pus, confirmed by microscopy that showed the absence of distinct concentric layers and coagulative necrosis, which are typically seen in sheep and goats raised in areas where the infection is endemic. In three cases amyloid deposits were observed in the liver and kidney. The C. pseudotuberculosis strains isolated were highly homologous to the reference strain ATCC 19410, except for some variability in their ability to ferment maltose and mannitol. Based on the production of nitrate reductase, 95 strains were attributed to the ovis biovar (nitrate reduction negative) and three to the equi biovar (nitrate reduction positive). All strains were sensitive to antibiotics, except to ampicillin (62.3% resistant strains) and gentamicin (83.7% resistant strains). Using an indirect enzyme-linked immunosorbent assay designed for CLA in sheep and goats, seven (58.3%) of 12 serum samples tested positive for antibodies.

[First choice treatment of the pediatric wrist ganglia]. / Trattamento di prima scelta degli igromi di polso in etá pediatrica.

AIM: The authors analyze the anatomical, etiopathogenetic and clinical characteristics of ganglia of the hand and especially the radio-carpus, which represent the most frequent cause of wrist swelling in pediatric age. They underline the importance of an adequate period of clinical observation and splint treatment, as the first methodical choice, rather than aspiration or surgical immediate resection. METHODS: The experience of the authors is based on splinting and/or surgical treatment on a series of 15 patients with wrist ganglion, with a follow-up of 4 years. The period of clinical observation had never been less than 6 months and the static splint had been recommended during nocturnal hours only, on a 3-4 month basis at least. RESULTS: Two thirds of the cases showed spontaneous re-absorption of the ganglion, while in the remaining third part a surgical indication of removal had been suggested, due to absence of spontaneous remission and the presence of trouble or pain in movements. The authors never practice the aspiration of the content of the ganglion, since recent literature advises against it due to the high percentage of recurrence observed. CONCLUSIONS: The clinical observation and the dedicated nocturnal splinting of the wrist ganglia in pediatric age represent the first treatment advocated. Surgery is suggested in cases unsolved with a conservative therapy. Aspiration is strongly discouraged.

Interaction of collagen-like peptide models of asymmetric acetylcholinesterase with glycosaminoglycans: spectroscopic studies of conformational changes and stability.

The effect of heparin on the conformation and stability of triple-helical peptide models of the collagen tail of asymmetric acetylcholinesterase expands our understanding of heparin interactions with proteins and presents an opportunity for clarifying the nature of binding of ligands to collagen triple-helix domains. Within the collagen tail of AChE, there are two consensus sequences for heparin binding of the form BBXB, surrounded by additional basic residues. Circular dichroism studies were used to determine the effect of the addition of increasing concentrations of heparin on triple-helical peptide models for the heparin binding domains, including peptides in which the basic residues within and surrounding the consensus sequence were replaced by alanine residues. The addition of heparin caused an increased triple-helix content with saturation properties for the peptide modeling the C-terminal site, while precipitation, with no increased helix content resulted from heparin addition to the peptide modeling the N-terminal site. The results suggest that the two binding sites with a similar triple-helical conformation have distinctive ways of interacting with heparin, which must relate to small differences in the consensus sequence (GRKGR vs GKRGK) and in the surrounding basic residues. Addition of heparin increased the thermal stability of all peptides containing the consensus sequence. Heparan sulfate produced conformational and stabilization effects similar to those of heparin, while chondroitin sulfate led to a cloudy solution, loss of circular dichroism signal, and a smaller increase in thermal stability. Thus, specificity in both the sequence of the triple helix and the type of glycosaminoglycan is required for this interaction.

Interaction of the collagen-like tail of asymmetric acetylcholinesterase with heparin depends on triple-helical conformation, sequence and stability.

The collagen-like tail of asymmetric acetylcholinesterase (AChE) contains two heparin-binding domains (HBDs) that interact with heparan sulphate proteoglycans, determining the anchoring of the enzyme at the basal lamina and its specific localization at the neuromuscular junction. Both HBDs are characterized by a cluster of basic residues containing a core with the BBXB consensus sequence (where B represents a basic residue and X a non-basic residue). To study the interaction of such HBDs with heparin we have used synthetic peptides to model the N-terminal and C-terminal sites. CD spectroscopy showed that all peptides are triple-helical at low temperatures, and undergo trimer-to-monomer transitions. Displacement assays of asymmetric AChE bound to heparin were performed using the peptides in both monomeric and triple-helical states. In the monomeric conformation, all the peptides were able to displace low levels of AChE depending on the basic charge content. In the triple-helical conformation, peptides containing the consensus sequence showed a large increase in the ability to displace bound AChE. Results suggest that the specific binding of the collagen-like-tail peptides to heparin depends both on the presence of the core sequence and on the triple-helical conformation. Moreover, BBXB-containing peptides that are less stable are more effective in displacing AChE, suggesting that the interaction region needs a significant amount of structural flexibility to better accommodate the ligand.

Studies of the denaturation patterns of bovine alpha-crystallin using an ionic denaturant, guanidine hydrochloride and a non-ionic denaturant, urea.

The effects of non-ionic and ionic denaturation and denaturation/renaturation on the native structure of alpha-crystallin at room temperature were examined. Native alpha-crystallin, at concentrations above and below the previously reported critical micelle concentration (CMC) range, was denatured by varying concentrations of urea and guanidine hydrochloride. The resulting denatured samples were examined by gel filtration fast performance liquid chromatography (FPLC), circular dichroism spectropolarimetry (CD), and transmission electron microscopy. Elution peak samples from gel filtration chromatography with sufficiently high concentrations were examined for subunit composition by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The studies presented herein demonstrate that the denaturation and renaturation of alpha-crystallin via non-ionic urea denaturation results in different renaturation species, depending upon the initial concentration of alpha-crystallin which is denatured and the concentration of urea, including certain species which, by gel filtration FPLC, have an apparent molecular weight greater than the native 800 kD aggregate. Transmission electron microscopy has also demonstrated the existence of a high molecular weight aggregate form for denatured samples. Ionic dissociation, in contrast, proceeds much in the same manner above and below the CMC range, the major difference occurring at 2 M guanidine hydrochloride. alpha B-crystallin is preferentially removed from the native alpha-crystallin aggregate upon treatment with 2 M guanidine hydrochloride indicating, once again, differences between the two subunits. Above and below the CMC range, dissociation with guanidine hydrochloride appears to plateau after 4 M guanidine hydrochloride as indicated by the presence of two apparent homotetrameric species and no further dissociation of these species with increasing guanidine hydrochloride concentrations. CD demonstrates that some secondary structure, which is lost with lower concentrations of alpha-crystallin, is still present when concentrations of alpha-crystallin, well above the critical micelle concentration range, are treated with high concentrations of urea at room temperature. In contrast, concentrations both above and below the CMC range demonstrate a significant loss of secondary structure upon treatment with 2 M guanidine hydrochloride. Finally, ionic denaturation and subsequent renaturation results in the formation of a species which is functionally incapable of protecting gamma-crystallin from heat-induced aggregation.

[Annular pancreas and neonatal duodenal occlusion. Presentation of 3 cases]. / Pancreas anulare e occlusione duodenale neonatale. Presentazione di 3 casi.

The authors report 3 cases of anular pancreas and consider the main clinical and differential diagnosis aspects of them. Afterwards they dwell upon the etiopathogenesis of this congenital malformation that is consequent not only upon extrinsic pancreatic compression but also upon a contemporary atresia or stenosis of duodenum. That however conditions the management; it will be apply to remove also the intrinsic obstruction of stenotic intestinal segment.

[Various cases of congenital lobar emphysema]. / Considerazioni su alcuni casi di enfisema lobare congenito.

The authors describe some cases of congenital lobar emphysema and after a review of literature discuss main clinical, radiological and differential diagnosis problems of this disease. At last they point out the favourable results obtained with the treatment performed (lobectomy with continuous pleural drainage and medical therapy of support).

Bullet embolism following gunshot wound of the chest. Case report and review of the literature.

A 24 year old male was shot in the low left posterior chest. Initial x-rays localized the bullet in the region of the left atrium or pulmonary veins. At 24 hours the bullet embolized to the right subclavian artery, totally occluding the vessel. The bullet was successfully removed, as was adjacent thrombus with complete restoration of distal pulses. Sixty-one cases with gunshot wound to the chest and 63 arterial emboli were reviewed. There was a mortality rate of 38%.