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A Vetere

Publications and source records attributed to A Vetere.

27 records · Page 2Linked to original sources
PubMed1992

Quantification of D-aspartate in normal and Alzheimer brains.

Using a new procedure to hydrolyze proteins without provoking racemization of the amino acids and using enzymatic methods to determine D- and L-aspartate (Asp), we have quantified the content of protein-bound D-aspartate (both D-aspartic acid and D-asparagine) of human brain white and gray matter proteins from normal and Alzheimer subjects. The D-enantiomer is present in brain proteins at mean concentrations between 0.48 and 0.90 mumol/g of wet tissue, corresponding to concentrations 34-82 times lower than that of L-aspartate. The highest levels of D-aspartate were found in Alzheimer gray matter (0.60-0.90, mean 0.69 mumol/g of wet tissue). When expressed as the percentage of total (i.e. D- plus L-) aspartate, %D = [D/(D + L)] x 100, the Alzheimer brains show a significantly higher content of D-aspartate in both gray matter (2.08%) and white matter (1.80%) than in the corresponding tissues of normal brains (1.65% in gray, 1.58% in white).

Alzheimer Disease↗
PubMed1991

Free D-aspartate and D-alanine in normal and Alzheimer brain.

In this report we present evidence for the presence of free D-aspartic acid (D-Asp) and D-alanine (D-Ala) in the white and gray matter of normal human brains and brains of individuals with Alzheimer's disease. D-Asp occurs at about the same concentration in the gray matter of both normal (18.6 nmol/g) and Alzheimer (14.8 nmol/g) brains, whereas in white matter its concentration is more than two times higher in normal than Alzheimer brains (22.4 and 10.5 nmol/g, respectively). D-Ala occurs in white matter at approximately the same concentration in both normal and Alzheimer brains (12.3 and 13.8 nmol/g, respectively), whereas in Alzheimer gray matter the D-Ala concentration is more than twice that found in normal gray matter (20.8 and 9.5 nmol/g, respectively). However, when the results are expressed as a percentage of D-amino acid/D+L, only small differences occur in all tissues examined.

Adult↗
PubMed1987

Characterisation of anaerobic curved rods (Mobiluncus spp.) isolated from the urogenital tract.

Thirty-two strains of anaerobic curved rods isolated from vaginal secretions and one isolated from seminal fluid were examined. Growth of all strains on solid media was superior to growth in liquid media, and at 37 degrees C they grew both anaerobically and in O2 5% in N2; they also grew anaerobically at 33 degrees C but not at 42 degrees C. No growth factors were identified, but strains grew more profusely at pH values above 5 X 0. The strains were screened in 80 biochemical tests, and for their susceptibility to 30 different antimicrobial agents. Most of the tests did not differentiate between the strains, but they were divided into four groups on the basis of cell morphology, metronidazole susceptibility, beta-galactosidase activity and arginine and hippurate hydrolysis. Group 1 consisted of 19 strains conforming to the species M. curtisi; group 2 consisted of five strains conforming to the species M. mulieris; group 3 consisted of five strains that resembled M. curtisi morphologically, and group 4 consisted of four strains that resembled M. mulieris morphologically, but the strains in the latter two groups reacted differently in at least one of the three major differential biochemical tests. Of three strains of M. curtisi and three of M. mulieris chosen at random, one of M. mulieris had a SDS-PAGE and fast-protein liquid chromatography protein profile indistinguishable from that of M. curtisi. We conclude that further efforts are required to clarify the taxonomic status of the genus Mobiluncus.

Anti-Bacterial Agents↗
PubMed1984

[In vitro activity of several cytostatic drugs against aerobic and anaerobic intestinal bacteria].

The human normal intestinal flora prevents the colonization of exogenous bacteria, maintaining a constant microecology: this property is called "colonization resistance". In leukemia patients antibiotics used for prevention and/or therapy of infectious episodes can alter the intestinal microecology, so that the gut can represent the trigger zone for generalized septicemia. Moreover cytotoxic drugs used in these patients can favour intestinal disturbances. In our study we evaluated the in vitro activity of three commonly used antineoplastic drugs (Daunorubicin, Cytosine arabinoside, Methotrexate) against aerobic and anaerobic intestinal bacteria and Clostridium difficile that is the aetiological agent of pseudomembranous colitis. Daunorubicin proved to be the most active inhibiting, in concentration ranging from 16 to 128 micrograms/ml, 50% of Bacteroides strains and 90% of Clostridium difficile and Enterococci strains tested. Methotrexate showed activity only against some Bacteroides strains, while Cytosine arabinoside had no activity at all. We conclude that in these patients the use of these drugs may represent another factor of risk altering the intestinal flora and so lowering the colonization resistance.

Bacteria, Aerobic↗
PubMedDate not supplied

Further study on the specificity of D-amino acid oxidase and D-aspartate oxidase and time course for complete oxidation of D-amino acids.

1. D-Amino acid oxidase (D-AAO) oxidizes: D-Met, D-Pro, D-Phe, D-Tyr, D-Ile, D-Leu, D-Ala and D-Val. D-Ser, D-Arg, D-His, D-norleucine and D-Trp are oxidized at a low rate. D-Ornithine, cis-4-hydroxy-D-proline, D-Thr, D-Trp-methyl ester, N-acetyl-D-Ala and D-Lys are oxidized at a very low rate. 2. D-Asp, D-Glu and their derivatives, Gly and all the L-amino acids are not oxidized (or are at a rate which is undetectable). 3. Among all D-amino acids, D-Met is the most highly oxidized compound. The Km value is 1.7 mM. 4. D-Aspartate oxidase (D-Aspo) either purified from Octopus vulgaris or from beef kidney oxidizes only D-Asp, D-Glu and their following derivatives: D-Asn, D-Gln, D-Asp-dimethyl-ester and N-methyl-D-Asp. 5. However, D-Pro, D-Leu, D-Ala and D-Met, are also oxidized by this enzyme, but at a very low rate (between 0.2 and 0.6% of D-Asp). 6. All other D-amino acids, glycine and all the L-amino acids are not oxidized. 7. Under experimental conditions, 1 U of D-AAO is able to totally oxidize 0.2 micromol of the following amino acids: D-Met, D-Pro, D-Phe, D-Thy, D-Ile, D-Leu, D-Ala, D-Val, D-Ser and D-Arg. 8. Similarly, 1 U of D-AspO in 1 hr of incubation totally oxidizes 0.1 micromol of D-Asp, D-Glu, D-Asn and D-Gln.

Amino Acid Oxidoreductases↗
PubMedDate not supplied

[Meigs' syndrome: its clinical picture and treatment].

Meigs' syndrome is a rare clinical entity characterised with ovarian benign tumour, ascites and hydrothorax. Between January '94-September '98 we observed three patients with: ovarian neoformation, light (1 patient), moderate (2 patients) monolateral pleural effusion, moderate (2 patients) and considerable (1 patient) ascites. In all patients the preoperative evaluation (sero-haematologic routine, Ca 125 and other oncologic markers, chest X-ray, abdominal and pelvic ultrasonography, total-body Tc, cytological analysis of pleural and abdominal effusion) was suggestive for malignancy but not confirmed it. So an explorative laparotomy with histological extemporary analysis was performed. The results were: 1 fibrothecomas, 1 fibroma, 1 ovarian inflammation with cystic luteinization areas and fibromatosis uterine. All three patients had a good postoperative course. The symptomatology and the effusions disappeared 7-10 days after operation. The first two cases were diagnosed as classic Meigs' syndrome, the third one, instead, as a pseudo-Meigs's syndrome. In conclusion the A.A., according to literature and their experiences, underline: 1) an ovarian mass with pleural and abdominal effusion not always represents an advanced malignancy; 2) even if elevated Ca 125 value is usually associated to a ovarian malignancy, there are some benign lesions in which we observed elevated level of this marker 3) the removal of the ovarian mass is the only resolutive treatment for these patients.

Aged↗
PubMedDate not supplied

[Morgagni-Larrey diaphragmatic hernia: report of a case].

The Authors presents a Morgagni-Larrey's diaphragmatic hernia case, observed during subocclusive manifestation. They emphasize the utility to perform always the surgical intervention, also in the asintomatic cases.

Female↗
PubMedDate not supplied

[Zenker's diverticulum. Apropos a case].

The authors report a case of Zenker's diverticulum in a patient 72 years old who underwent surgery. The pharyngoesophageal function was investigated before and after cricopharyngeal myotomy and diverticulopexy, with oesophageal manometry. Preoperative manometry showed an incomplete relaxation of the upper oesophageal sphincter and increased of pharyngeal pressure. This diverticulum has a pulsion pathogenesis and in this case is not associated with gastroesophageal reflux. It is important to check whether an associated oesophageal pathology exist once Zenker's diverticulum has been diagnosed: X-ray examination of oesophagus and stomach are capable of identifying the presence of diverticulum as well as other pathological association. In the case showed the clinical manifestation are represented by: cervical dysphagia, sensation of foreign body while eating due to the accumulation of ingested food in the diverticulum, and noisy deglutition. The surgical treatment in this case consist of diverticulopexy with cricopharyngeal myotomy. This case is treated with diverticulopexy for two reason: because is not very big and to reduce post-operative period. In conclusion the authors shows the importance of this surgery for not very large sized pouches, and emphasise the importance of manometric and radiographic control in pre and post-operative period. This kind of surgery reduce post-operative complication and the period to stay in bed.

Aged↗