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Biomedical subjects

A Rocchi

Publications and source records attributed to A Rocchi.

At least 19 recordsLinked to original sources
PubMed1998

Nucleotide sequence and chromosomal mapping of the 5S rDNA repeat of the crustacean Proasellus coxalis.

In this investigation we analysed the 5S rRNA genes of the isopod crustacean Proasellus coxalis, 5S rDNA hybridization of digested genomic DNA and amplification by PCR demonstrate that these genes are organized in tandem repeats of 589 bp, 120 of which represent the coding sequence and 469 the spacer sequence. Proasellus coxalis is the first crustacean species in which 5S rRNA genes have been found tandemly arranged without being linked to other repeated genes. The PCR product has been used as a probe in FISH to locate the 5S rRNA genes on two chromosome pairs of the P. coxalis karyotype. Comparison of the 5S rRNA sequence of this species with previously published sequences of six other crustacean species shows the existence of a good correlation between phylogenetic relationships and sequence identity.

Animals↗
PubMed1997

Longitudinal differentiation of chromosomes of Asellus aquaticus (Crust. Isop.) by in situ nick translation using restriction enzymes and DNase I.

Asellus aquaticus is an isopod crustacean whose chromosomes cannot be differentiated by G- or R-banding techniques. In this work, we have obtained a longitudinal differentiation of these chromosomes by in situ nick translation using restriction enzymes (HaeIII, DraI and BamHI) and DNase I digestions. The four nucleases, with different efficiencies, have produced similar labelling patterns. Staining with DAPI, Giemsa and chromomycin A3 reveals that the DNA of the nick-translated regions is generally more resistant to extraction from the chromosome. The results obtained on the heteromorphic sex chromosome pair observed in about a quarter of the males of a natural population allow several hypotheses to be advanced on the nature and origin of chromosome dimorphism.

Animals↗
PubMed1996

Heterochromatin and ribosomal genes in Asellus aquaticus (Crust. Isop.).

In the present investigation chromosomal preparations of Asellus aquaticus were sequentially stained with chromomycin A3 to reveal the heterochromatic areas, hybridized in situ with rDNA probes in order to map the ribosomal genes and finally silver stained to check the transcriptional activity of these genes. The results indicate the existence of a substantial correspondence of location and size among the heterochromatic regions and the regions over which the in situ hybridization signals spread. The ribosomal genes, quite independently of their location in the secondary constriction, can be silver stained and thus appear to be transcriptionally active. The ribosomal sequences also hybridize to the entire heterochromatic areas observed on the probable Y chromosome identified in some males of a natural population. These rRNA genes are only rarely transcriptionally active.

Animals↗
PubMed1995

Study of the relationships between common fragile sites, chromosome breakages and sister chromatid exchanges.

This paper reports the results of an investigation into the relationship between common fragile sites and sister chromatid exchanges (SCE). Human leukocyte cultures were grown in two different media, one complete (RPMI 1640) and one deficient in folic acid and thymidine (199M). Some of the cultures were treated with DAPI, a non-intercalating compound which binds preferentially to the AT bases of DNA and is capable of inducing fragile sites. Bromodeoxyuridine (BrdU) was added to all the cultures for SCE analysis. Chromomycin A3 was used for mapping lesions and SCEs by R-banding. A total of 400 cells was examined. The main results show that: BrdU, probably by re-equilibrating the unbalanced nucleotide pool of the 199 culture medium, interferes with the synergism between this culture medium and DAPI in inducing the expression of fragile sites; the SCE frequency per cell is not increased by DAPI in both culture media, therefore this compound does not seem to cause any damage to the DNA and seems merely to act by inhibiting the normal condensation of a subset of fragile sites that possess DAPI-specific base sequences; even in the absence of chromosomal lesions, the fragile sites are significantly preferred as SCE sites to non-fragile sites, whereas in the presence of a lesion, both fragile and non-fragile sites have the same likelihood of undergoing SCE. All this indicates that the presence of a lesion strongly favours SCE formation and that common fragile sites are probably chromosome regions preferentially damaged during the S phase.

Bromodeoxyuridine↗
PubMed1995

Health-related quality of life in patients with major depression who are treated with moclobemide.

A total of 651 depressed patients completed self-administered health-related quality-of-life (HRQOL) questionnaires during treatment with moclobemide in order to evaluate whether general and psychopathology-specific HRQOL questionnaires could detect changes in depressed patients receiving treatment. Patients were treated with moclobemide on an outpatient basis over an 8-week period; questionnaires were completed at weeks 0, 2, 4, and 8. At each assessment, patients completed one of two HRQOL questionnaires: namely, the General Health Questionnaire (GHQ), a psychopathology-specific HRQOL questionnaire, or the Short-Form 36 (SF-36), a general HRQOL instrument. Physicians were randomized to one of the two HRQOL questionnaires for all of their patients. Because the French version of the SF-36 was not available in the public domain, the patients of all Francophone physicians completed the GHQ, whereas the patients enrolled by Anglophone physicians completed either the SF-36 or the GHQ. The GHQ provides an overall score that measures the emotional dimensions of HRQOL, whereas the SF-36 provides scores in the following eight domains: physical functioning (PF), physical role functioning (PRF), emotional role functioning (ERF), social functioning (SF), bodily pain (BP), mental health (MH), vitality (VT), and general health perceptions (GHP). The GHQ and seven domains of the SF-36 detected a statistically significant linear trend (improvement) over time (p < 0.05). The change in the BP domain of the SF-36 was not statistically significant (p = 0.29).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

Impact of chemotherapy-associated nausea and vomiting on patients' functional status and on costs: survey of five Canadian centres.

OBJECTIVE: To estimate the effect of chemotherapy-associated nausea and emesis on patients' functional status and on costs to the health care system, the patients and society before antagonists to the serotonin (5-hydroxytryptamine) receptor subtype 5-HT3 became available. DESIGN: A 5-day prospective survey between February and May 1991 of patients receiving chemotherapy for cancer. Data were obtained from questionnaires completed by nurses and patients. SETTING: Five Canadian cancer treatment centres in Ontario (three) and Quebec (two). PATIENTS: Outpatients and inpatients 18 years of age and older who were scheduled to receive chemotherapy with a moderate to high potential for emesis as defined by standardized criteria. Patients were excluded if they were scheduled to receive an investigational antiemetic or had received chemotherapy within the previous 7 days. Of the 128 who were eligible, 112 agreed to participate; 107 returned the completed questionnaire, but the data for 15 were excluded because the patients received multiple-day chemotherapy. MAIN OUTCOME MEASURES: The degree of nausea (on a seven-point scale) and the frequency of emesis (vomiting or retching) were recorded for each day of the survey. Functional status was assessed before and after chemotherapy by means of the Functional Living Index-Emesis (FLIE). The direct health care costs and the indirect costs (e.g., of time off work) associated with nausea and emesis were estimated from the survey responses and secondary data sources. RESULTS: On the day of chemotherapy 38 of the 92 patients (41%) experienced emesis with or without nausea, and over the 5 days of the survey 72 patients (78%) reported at least one episode of nausea or emesis. The absolute risk of either problem decreased over time, but the risk of nausea relative to emesis increased over time. The FLIE scores indicated significant worsening of functional status after chemotherapy. On the day after treatment the main impact was from emesis, particularly with regard to leisure activities, household tasks and hardship to the family. Nausea had a significantly greater impact than emesis on overall functioning. The additional direct health care cost for managing emesis was estimated to be $63 and the indirect cost $121. CONCLUSIONS: Despite prophylaxis with antiemetic drugs, nausea and emesis were significant problems in this population receiving chemotherapy. The management of emesis consumed relatively small amounts of health care resources, but there were costs outside the hospital for patients and others.

Activities of Daily Living↗
PubMed1992

The effect of caffeine on DAPI-inducible fragile sites.

DAPI is a non-intercalating compound which binds specifically to the AT bases of DNA. When leukocytes are grown in complete medium (RPMI 1640) DAPI induces the expression of three fragile sites on human chromosomes and if the medium is deficient in folic acid and thymidine (199M) it induces 19 fragile sites. Caffeine has been found by different authors to considerably enhance the expression of chromosome breaks which have been produced by other agents. When it is added to the complete medium after DAPI, it elicits almost all the sites that DAPI only induces in incomplete medium. When caffeine is added after DAPI to incomplete medium, it does not significantly or unidirectionally modify the capacity of the two subjects examined to elicit fragile sites. The analysis of these results, when correlated with that of the mitotic index, reveals a different sensitivity of the two subjects to the combined DAPI-caffeine treatment. The results are quite compatible with the hypothesis that the DAPI-induced fragile sites are DNA regions which are not accurately replicated during the S phase.

Caffeine↗
PubMed1991

GATA repeats in the genome of Asellus aquaticus (Crustacea, Isopoda).

A 500 bp fragment of Drosophila genomic DNA containing 37 copies of the tetranucleotide GATA was used to probe, by Southern DNA blotting and in situ hybridization, two natural populations of the isopod crustacean Asellus aquaticus collected from the Sarno and Tiber rivers. This species does not have a recognizable sex chromosome pair. In a number of males from the Sarno population chromomycin A3 staining reveals a heteromorphic chromosome pair. The heterochromosome has two blocks of heterochromatin. After digestion of genomic DNA with six restriction endonucleases and hybridization with the GATA probe, the two populations exhibit different fragment length patterns. No sex-linked pattern was observed in either population. In situ hybridization to chromosomes of males and females from the Sarno population does not reveal any sex-specific pattern of labelling and indicates a scattered distribution of GATA sequences on most chromosomes with some areas of preferential concentration. The heterochromatic areas of the male heterochromosome are not labelled.

Animals↗
PubMed1991

[Acquired cystic kidney disease among hemodialysis patients: echographic and clinical study].

Thirty-six of 56 (64%) patients on chronic hemodialysis for 1 to 194 months were found to have ACKD (at least 3 cysts per kidney) by means of ultrasonographic evaluation. The number, size and extent of cysts were positively and significantly correlated with the months on hemodialysis. There was also a significant positive correlation between grade of ACKD and Hb. Moreover there was a significant positive association of abdominal pain; none had suffered from hemorrhage or neoplasm.

Abdominal Pain↗
PubMed1991

[Radiologic and clinical aspects of osteoarticular amyloidosis caused by dialysis].

Many long-term (greater than 60 months) hemodialysis patients develop a severe osteoarticular disease, called "dialysis arthropathy", which is characterized by the deposition in bone and synovia of a new type of amyloid made mainly of beta 2-microglobulin. In the present study, 31 patients (17 males, 14 females; age 54.1 +/- 13 years), undergoing chronic hemodialysis for 60-125 months, were examined for dialysis arthropathy by means of clinics and of radiological investigations (conventional radiography and computed tomography). Sixteen patients (51.6%) had radiographic evidence of dialysis arthropathy: geodes (shoulders, 12 cases; wrists, 11; hips, 2; knees, 2) and/or destructive arthropathies (cervical spine, 13 cases, dorsolumbar spine, 2; hands, 2; hips, 1). Within 24 months, these lesions were found to progress slowly in the majority of cases. In the diagnostic process, CT should be employed in the study of spine, shoulders and hips when the lesions have not been sufficiently demonstrated by conventional radiography in the presence of evident clinical signs. Patients with dialysis arthropathy had undergone dialysis for longer periods than those without it (p less than 0.005) and showed a significantly higher incidence of both carpal tunnel syndrome (p less than 0.0005) and shoulder pain (p less than 0.005). Our findings confirm the high incidence and clinical importance of dialysis arthropathy in long-term hemodialysis patients and the value of diagnostic imaging in screening such patients for those lesions.

Adult↗
PubMed1991

[Diagnostic imaging for the study of popliteal masses in dialyzed patients].

A new type of amyloidosis, secondary to the massive deposition of beta 2-microglobulin, has been identified which is peculiar to long-term (greater than or equal to 5 years) hemodialysis. Popliteal masses have recently been described as a possible manifestation of this type of amyloidosis. We report the results of a clinical-radiologic study of the popliteal region in 28 patients (14 males, 14 females; age 52.9 +/- 12.6 years) undergoing chronic hemodialysis for 60-212 months (mean 127 +/- 40). We aimed at determining the role of diagnostic imaging (conventional radiography, ultrasonography, Computed Tomography) in this pathologic condition. Clinics detected popliteal masses in 4 patients (bilateral in 1). US allowed 2 more cases to be detected and demonstrated the cystic nature of the lesion. Ultimately, popliteal masses could be demonstrated in 6 (bilateral in 5) of 28 patients (incidence 21.4%). In the 3 patients who were investigated by CT, cysts were seen to communicate with the joint cavity (Baker's cysts). In 1 case, immunocytochemical analysis showed diffuse beta 2-microglobulin positive amyloid deposition within the synovial wall of the surgically removed cyst. All the 6 patients experienced some of the major features of dialysis-related amyloidosis: carpal tunnel syndrome (6 cases), destructive arthropathy (5 cases), carpal and shoulder bone radiolucencies (5 and 4 cases, respectively). These findings, while documenting the high prevalence of popliteal cysts among long-term hemodialysis patients and the strong correlation with dialysis-related amyloidosis, stress the importance of diagnostic imaging in the detection and follow-up of such lesions.

Adolescent↗
PubMed1990

[Osteo-articular amyloidosis caused by dialysis. Clinical and radiologic aspects].

Twenty-nine patients who had received chronic hemodialysis for more than 5 years provided the material for the present study. In 12 of them (41%) there were radiological findings of dialysis related amyloidosis, mainly destructive spondyloarthropathy of the cervical spine (n = 11) and geodes of the shoulder (n = 5). When compared with negative patients, these patients were significantly older (p less than 0.001 and had been dialyzed for longer periods of time (p less than 0.01). Moreover, in such patients there was an higher incidence of carpal tunnel syndrome (p less than 0.025) and shoulder pain (p less than 0.001). Our results confirm that osteoarticular amyloidosis is a frequent long-term complication of chronic hemodialysis and underline the correlation between clinical and radiological findings.

Adult↗