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Biomedical subjects

D Quaglino

Publications and source records attributed to D Quaglino.

At least 73 records · Page 4Linked to original sources
PubMed1996

The effect of age on hemopoiesis.

Although several workers have described numerous changes affecting the hemopoietic system during senescence, the existence of univocal "hematological disease" closely related to the elderly is controversial. Many of the hematological changes described, such as sideropenic or megaloblastic anemia, are frequently the consequence of the different pathological conditions which often affect elderly patients. This review will consider the most important alterations of hemopoiesis and coagulation in the elderly, the causes capable of influencing hematological changes in old people, and their pathogenesis. Some of the major diagnostic problems encountered in the management of elderly subjects with hematological changes are also addressed. In the presence of an elderly patient with hematological alteration, it is necessary to follow a precise diagnostic schedule, which should first of all exclude the presence of a primary hematological disorder, and consider the different extrahematological conditions which frequently occur in elderly subjects (malignancies, malnutrition, chronic infections from immunological abnormalities, hormonal changes, deficiencies of various organs and systems etc.) and are responsible for many different hematological changes. These must be tackled rationally so that treatment may not only be symptomatic, but may also directly intervene on the cause of the disorder.

Aging↗
PubMed1996

[Alcohol consumption and coronary disease in men].

It has been recently suggested by many epidemiological studies, and emphasized by a nonspecialistic press, that a moderate alcohol intake may exert a protective role in coronary heart diseases. In our study, by means of a questionnaire, the consumption of alcohol in 100 male patients, less than 70 years old, affected by myocardial infarction and/ or angina pectoris, has been evaluated during a period before and after the admission to our Coronary Care Unit. On the basis of their alcohol intake, patients were divided into five categories: abstainers (8%), daily intake lower than one drink (7%), between one and two drinks (8%) between three and four drinks (46%) and equal or higher than five drinks (31%). In the light of these results, we suggested that, in our region (a country area in the north-east of Italy), there are higher levels of ethanol intake compared to those reported by other authors, that these parameters are only slightly modified by the occurrence of coronary heart diseases and that alcohol consumption, although low and moderate, must be therefore emphasized with extreme caution.

Aged↗
PubMed1996

Ultrastructural and morphometrical evaluations on normal human dermal connective tissue--the influence of age, sex and body region.

In order to give detailed structural and quantitative evaluations for some of the most important dermal constituents such as collagen, elastic fibres and mesenchymal cells, and for the non-structured extracellular matrix, we performed ultrastructural investigations on dermal biopsies from 50 healthy caucasian subjects aged from 6 fetal months to 83 years. Striking changes were observed, mainly in the perinatal period, for collagen, elastin and mesenchymal cells and, after 50 years of age, for collagen and elastin. Only slight or negligible differences were noted between males and females and in skin specimens taken from different parts of the body but similarly exposed to environmental factors (i.e. UV radiation). Modifications of the non-structured extracellular matrix appeared to be the consequence of changes affecting the other components. The results, therefore, emphasize the importance of the ageing factor in connective tissue metabolism and give further information on both qualitative and quantitative characteristics of normal human dermis.

Adolescent↗
PubMed1996

Earthworm coelomocytes in vitro: cellular features and "granuloma" formation during cytotoxic activity against the mammalian tumor cell target K562.

Earthworms possess specific, adaptive, cellular immunodefense as well as non-specific responses found in other complex metazoans. Here we characterized coelomocytes from the earthworm Eisenia foetida by electron microscopy and cytofluorimetric analyses, and investigated structural changes that occur when effector coelomocytes and target K562 erythromyeloid human tumor cells interact during cytotoxic activity. In in vitro cultures 1) the two earthworm cell types (i.e. small and large coelomocytes) retained their morphological features; 2) their DNA content was significantly less than that of human lymphocytes and the erythromyeloid human tumor cell line K562; 3) significant percentages of coelomocytes were found to be in S or G2/M phases of the cell cycle. When cultivated alone for up to 3 h, coelomocytes formed no aggregates. However, when mixed with K562, coelomocytes spontaneously killed tumor cells, and cytotoxic reactivity was accompanied by the formation of multiple aggregates similar to granulomas. These results are the first to describe this type of earthworm non-specific "inflammatory" response in vitro against tumor cells.

Animals↗
PubMed1996

Connective tissue in skin biopsies from patients suffering systemic sclerosis.

Little information is available on elastin during systemic sclerosis since biochemical and morphological data have primarily focused on collagen and glycosaminoglycan alterations of connective tissues in this pathological process. We performed ultrastructural, morphometric, biochemical and in situ hybridisation analyses on skin biopsies from patients affected by scleroderma and from site and age-matched control subjects. Affected skin revealed alterations in the distribution and organisation of collagen bundles and fibrils together with zonal increase of the microfibrillar component. Elastic fibres were significantly more numerous than in control skin, were more frequently vacuolated and characterised by electron-dense inclusions; moreover, morphometric analysis provided evidence for a significant increase of the percentage of both collagen bundles and elastin fibres in the measured tissue, compared to normal skin. Biochemical analysis seemed to confirm the increased elastin content per unit of dried weight tissue in sclerodermic skin. Differences observed among patients were only partially associated with disease duration and/or to severity of clinical manifestations. The abnormal amount of elastic fibres observed in skin biopsies from patients, and data from in situ hybridisation suggest the presence of a deregulation of the whole extracellular matrix that might be related to the role of cytokines such as TGF-beta, which has already been suggested to be involved in systemic sclerosis and in enhanced collagen and elastin production.

Adult↗
PubMed1996

Secondary leukaemias. Clinical and cytobiological aspects.

Patients treated with radiation and cytotoxic agents for a variety of neoplastic conditions develop with increased frequency a secondary leukaemia, usually a form of acute myeloblastic leukaemia. The authors illustrate and discuss the various morphological and cytobiological which characterize the "preleukaemic phase", and which comprise myelodysplastic alterations, cytochemical abnormalities, concerning the presence of glycogen and free iron in the red cell series, as well as a number of changes in enzymatic activities in the myeloid series, cytokinetic changes, indicative of accumulation of cells in G0 and G1, cytogenetic non-random abnormalities, involving specific chromosomes, and finally in vitro cultures which show a reduction in colony formation. The authors underline the differences between primary and secondary preleukaemic myelodysplastic states, consisting in the presence in the latter of frequent hypocellularity, fibrosis and almost invariability a clear involvement of multiple cell lines.

Chromosome Aberrations↗
PubMed1995

Mitochondrial mass and membrane potential in coelomocytes from the earthworm Eisenia foetida: studies with fluorescent probes in single intact cells.

Earthworm coelomocytes exist in two forms, i.e., small (SC) and large (LC) cells, as demonstrated by velocity sedimentation, electron microscopy, and FCM. However, we know little concerning the functional activities of various, important organelles, such as mitochondria. In comparison with SC, LC from Eisenia foetida have a higher number of mitochondria, and, accordingly, showed a greater fluorescence intensity when mitochondrial mass was measured by nonyl acridine orange and FCM. To measure MMP we used both the lipophilic cationic probe JC-1 and Rh123. The intracellular localization of JC-1 in SC and LC was observed by fluorescence microscopy. Using JC-1, MMP was analyzed separately on SC and LC by FCM, and significant percentages of coelomocytes (> 95% of SC and about 90% of LC) displayed a high MMP. Adding 0.1 microM VAL caused most SC to depolarize, while this occurred in only a few LC. Rh123 gave different results: no effects of VAL were observed either in SC or in LC. In coelomocytes there may be several energy-independent Rh123-binding sites whose role must still be elucidated. On the whole, these data indicate that it is possible to analyze mitochondrial parameters by FCM in intact invertebrate coelomocytes, and that the type of cell and the probe used have a critical importance.

Animals↗
PubMed1995

Autogeneic but not allogeneic earthworm effector coelomocytes kill the mammalian tumor cell target K562.

Earthworm coelomocytes have been used as effector cells against the human tumor target, K562. To first assess the viability of effectors, incorporation of [3H]-thymidine was tested and was higher in autogeneic (A<==A, self) than in allogeneic (A<==>B, nonself) coelomocytes. A<==>A showed significantly greater numbers in S, G2, or M phases than A<==>B coelomocytes. When A<==>A or A<==>B were cultured, no significant cell killing occurred in either, as measured in a 4-hr 51Cr release assay. A<==>A but not A<==>B killed K562 target cells. Cytotoxicity was dependent upon membrane binding between small, electron-dense coelomocytes and targets; it was enhanced by adding PHA. The heat labile supernatant from A<==>A but not from A<==>B killed K562 targets after cultivation for 10 min at 22 degrees C, but not immediately after washing. Recognition of, binding to, and killing of foreign cells in a natural killer cell-like reaction may reflect natural immunity in earthworms.

Animals↗
PubMed1995

Duodenal ferritin synthesis in genetic hemochromatosis.

BACKGROUND/AIMS: The molecular defect of genetic hemochromatosis (GH) is unknown. It is believed that low expression of duodenal ferritin in GH is caused by tissue or cell specific defect of ferritin synthesis. Our study was designed to ascertain whether the control of duodenal ferritin synthesis in GH was defective. METHODS: Expression at the single cell level of H and L ferritin messenger RNAs and protein and activity of the iron regulatory factor, which controls the translation of ferritin messenger RNA, were assessed in 43 duodenal biopsy specimens from individuals with GH, secondary hemochromatosis (SH), anemia, or normal iron balance. RESULTS: Signal for ferritin H and L subunit messenger RNAs was detected in both absorptive and nonabsorptive cells by in situ hybridization, but in 10 of 14 patients with untreated GH, the signal was lower than in patients with SH or normal subjects. However, immunostaining for ferritin protein documented a diffuse/cytoplasmic pattern, whereas a supranuclear/granular staining was found in normal subjects or patients with SH. The spontaneous activity of duodenal iron regulatory factor was consistently higher in patients with GH than in normal subjects or subjects with anemia or SH. CONCLUSIONS: In patients with GH, ferritin gene transcription is preserved in both absorptive and nonabsorptive intestinal cells. Low accumulation of ferritin is not caused by a defective control of ferritin synthesis but by low expression of ferritin messenger RNA and sustained activity of iron regulatory factor.

Adolescent↗
PubMed1995

Transforming growth factor-beta reverses a posttranscriptional defect in elastin synthesis in a cutis laxa skin fibroblast strain.

Skin fibroblasts from two cases of autosomal recessive cutis laxa (CL), having insignificant elastin production and mRNA levels, were challenged with transforming growth factor beta-1 (TGF-beta 1). Elastin production was brought from undetectable values to amounts typical of normal human skin fibroblasts in a dose-dependent fashion. Basic fibroblast growth factor (100 ng/ml) alone or in combination with TGF-beta 1 reduced elastin production and mRNA expression in CL skin fibroblasts more extensively than in normal cells. In situ hybridization showed that these effects were at the transcript level. One of the CL strains was examined in detail. Transcription rates for elastin were similar in normal and CL and unchanged by TGF-beta 1 or TGF-beta 2 (10 ng/ml), while in CL elastin mRNA half-life was increased > 10-fold by TGF-beta 2 and reduced 6-fold after TGF-beta 2 withdrawal, as compared with a control strain. Cycloheximide partially reversed elastin mRNA instability. These data are consistent with a defect in elastin mRNA stability that requires synthesis of labile factors or intact translational machinery, resulting in an extremely low steady state level of mRNA present in this strain of CL. Furthermore, TGF-beta can relieve elastin mRNA instability in at least one CL strain and elastin production defects in both CL strains.

Cells, Cultured↗
PubMed1995

Subclinical coeliac disease is a frequent cause of iron-deficiency anaemia.

BACKGROUND: Although it is known that anaemia may be the only presenting symptom in coeliac disease, prevalence figures of unsuspected coeliac disease in anaemic patients are not available. The aim of this study was to assess the clinical usefulness of antigliadin and antiendomysial antibody tests in the diagnostic algorithm of anaemic patients. METHODS: Two hundred consecutive anaemic patients were tested for antigliadin antibodies, and those positive were also tested for antiendomysial antibodies. All patients positive for antigliadin and antiendomysial antibodies underwent intestinal biopsy. RESULTS: Sixteen patients were antigliadin antibody-positive, and 10 were also antiendomysial antibody-positive. In all 10 a jejunal biopsy was consistent with coeliac disease (prevalence, 5%). This prevalence rose to 8.5% when patients with macrocytic anaemia or with microcytic anaemia due to previous bleeding or responsive to oral iron therapy were excluded from the calculation. CONCLUSIONS: Coeliac disease is a frequent cause of iron-deficiency anaemia, and antigliadin and antiendomysial antibody tests should be always performed in the diagnostic algorithm of anaemic patients.

Adult↗
PubMed1995

Ultrastructure of elastin.

Almost all structural studies on elastin have been done in higher vertebrates, in which it is organized as an extracellular network of branched fibres which vary from fractions f microns to several microns in diameter. By conventional electron microscopy, elastin appears amorphous. By both freeze-fracture and negative staining on cryosections, it can be resolved as beaded filaments 5 nm in diameter forming a 3D meshwork that, upon stretching, becomes oriented in the direction of the force applied. This filamentous aggregation of elastin molecules is confirmed in vitro by the observation that its soluble precursor, tropoelastin, shows a strong tendency to associate into short 5 nm-thick filaments that, with time, become longer and aggregate into bundles of various dimensions. If chemically fixed and embedded, these aggregates appear amorphous and identical to natural elastin fibres. The tendency of tropoelastin to aggregate into 4-5 nm-thick beaded filaments, which then associate into 12 nm-thick filaments forming a 3D network, has been observed by atomic force microscopy for recombinant human tropoelastin. Therefore, the amorphous structure of elastin seems to be a technical artefact. Apart from elastin-associated microfibrils, which are always present at the periphery of growing elastic fibres and probably have a role more complex than being a scaffold for tropoelastin aggregation in vivo, the elastic fibres seem to be composed of several matrix constituents, which are different in different organs and change with age and in pathological conditions. This is demonstrated by immunocytochemical studies on ultrathin sections.

Animals↗
PubMed1994

Apoptotic cell death in the mouse limb and its suppression in the hammertoe mutant.

We examined the importance of cell death in producing the limb deformity phenotype of the Hammertoe mouse. In order to make this evaluation, we first combined several techniques to verify the reliability of cell death markers in the normal mouse limb. In the normal limb, cell death occurs between Days 10.5 and 15.5 in the anterior, interdigital, and posterior zones. Morphological examination and staining for acid phosphatase or macrophages all reveal regions of cell death by detecting phagocytosis, while in situ end labeling of DNA defines nuclear degeneration as apoptotic. The phagocytes display surface markers characteristic of macrophages. The Hammertoe mutant shows strongly reduced cell death only in the interdigital region. This result is consistent with the phenotype and suggests that the mutation influences the patterning or control of cell death rather than its mechanism.

Animals↗
PubMed1994

Elastin production and degradation in cutis laxa acquisita.

A case of cutis laxa acquisita was studied with the aim of defining the molecular defects involved and comparing them with those of an inherited form of cutis laxa. In the acquisita form of cutis laxa ultrastructural and biochemical observations confirmed a dramatic reduction of dermal elastin, whereas collagen content was normal. Elastin mRNA expression as well as tropoelastin production by dermal fibroblasts, in vitro, were normal compared with control cells, as revealed by in situ hybridization and enzyme-linked immunosorbent assay, respectively. Lysyl oxidase activity, measured on cultured fibroblasts, was reduced to 60% compared with age-matched control subjects. Unlike control skin fibroblasts or fibroblasts from inherited cutis laxa, the affected skin cells from cutis laxa acquisita predominantly expressed an elastolytic activity identified as cathepsin G. Patient serum also has reduced elastase inhibitory capacity and reduced levels of alpha 1-antiproteinase inhibitor (alpha 1-antitrypsin). Although cutis laxa acquisita is a heterogeneous group of disorders, findings in this patient were consistent with excessive loss of cutaneous elastin due to the combined effects of several factors, such as low lysyl oxidase activity together with high levels of cathepsin G and reduction of circulating proteinase inhibitor(s).

Adult↗
PubMed1994

Serological screening of coeliac disease: choosing the optimal procedure according to various prevalence values.

The aim of this study was to select the best approach for screening coeliac disease patients among populations with different grades of disease prevalence. The diagnostic performance was assessed of class A and G antigliadin antibodies and class A antiendomysium antibodies in 93 consecutive outpatients with suspected malabsorption, 44 of whom (47%) had coeliac disease according to duodenal histological tests. Class G antigliadin antibodies provided the worst diagnostic values, whereas a high diagnostic validity was found for the other two tests. The positive predictive value corrected for the disease prevalence expected in coeliac disease relatives (5%) and the general population (0.2%) fell to 30% and < 2% respectively for class A antigliadin antibodies, whereas it remained 100% for antiendomysium antibodies in both situations, providing an optimal value for their use as a screening test and as a valid alternative to duodenal biopsy when this is not feasible. The high cost of anti-endomysium antibodies and the invasive nature of duodenal biopsy prevent them being used widely as screening procedures. A cost effective two step approach was simulated measuring class A antigliadin antibodies in all subjects of the target population (first step), and performing a confirmation test (antiendomysium antibodies or duodenal biopsy) only in subjects positive for antigliadin antibodies. The results show that such a procedure should be recommended only for subjects with an expected low disease prevalence--that is, 5% for coeliac disease relatives and 0.2% for the general population--as the positive predictive value was always 100% with an acceptable false negative rate (6% and 11% respectively), irrespective of which of the two confirmation tests was used. This approach avoids the use of the confirmation test in 63% and 89% of subjects respectively for the two levels of prevalence, resulting in a considerable reduction of the cost. Patients seen for suspected malabsorption with an expected high prevalence of coeliac disease should not have such a serological screening procedure. In conclusion, antigliadin antibodies are useful to screen for asymptomatic coeliac disease in non-hospital communities if antiendomysium anti-bodies are used as a confirmation test: the latter is reasonable valid alternative to duodenal biopsy.

Adolescent↗
PubMed1994

SP-A, SP-B, and SP-C in surfactant subtypes around birth: reexamination of alveolar life cycle of surfactant.

Transformations of surfactant after secretion are incompletely understood. To clarify them, we lavaged lungs in fetuses and in newborn rabbits, fractionated the lavage fluid by differential and density gradient centrifugation, and analyzed the distribution of surfactant protein (SP) phospholipids, SP-A, SP-B, and SP-C. Furthermore, we administered into trachea of newborn rabbits labeled surfactant and compared the alveolar clearance of SP-A, SP-B, SP-C and saturated phosphatidylcholine. We found that, in the fetus, secreted lamellar bodies contain all components of surfactant, except a small amount of SP-A. As breathing starts and new surfactant subtypes are generated, the proteins are mostly associated with dense subtypes, but SP-B and SP-C are especially concentrated in dense materials that contain minor amounts of phospholipids and SP-A. Furthermore, we found that, during breathing, alveolar surfactant is degraded into more than one type of remnant, that the lavage fluid contains a pool of SP-A not associated with membranes, and that SP-A, SP-B, and SP-C are all turned over at a faster rate than saturated phosphatidylcholine.

Animals↗
PubMed1993

Epididymal lymphoma. A case report.

Primary epididymal lymphoma is an unusual observation. Only 2 cases of non-Hodgkin's lymphoma of the epididymis have been previously reported. We describe the clinical and pathologic features and management of a primary high-grade malignant lymphoma of the epididymis in which a tentative diagnosis of lymphoma was made on the basis of cytologic examination and immunochemical staining of the material obtained from an aspiration needle biopsy.

Aged↗