PubMed Health⌕ Search

Biomedical subjects

G Giudice

Publications and source records attributed to G Giudice.

At least 19 recordsLinked to original sources
PubMed2005

Stress response in mesoangioblast stem cells.

Stem cells are presumed to survive various stresses, since they are recruited to areas of tissue damage and regeneration, where inflammatory cytokines and cytotoxic cells may result in severe cell injury. We explored the ability of mesoangioblasts to respond to different cell stresses such as heat, heavy metals and osmotic stress, by analyzing heat shock protein (HSP)70 synthesis as a stress indicator. We found that the A6 mesoangioblast stem cells constitutively synthesize HSP70 in a heat shock transcription factor (HSF)-independent way. However, A6 respond to heat shock and cadmium treatment by synthesizing HSP70 over the constitutive expression and this synthesis is HSF1 dependent. The exposure of A6 to copper or to a hypertonic medium does neither induce HSP70 synthesis nor activation of HSF1, while a constitutive binding of constitutive heat shock element binding factor was found. Together, these data suggest that mesoangioblasts constitutively express HSP70 as an 'a priori' activation mechanism, while they maintain the ability to respond to stress stimuli.

Animals↗
PubMed2005

Factors which influence sperm ability to fertilize.

Different factors influence animal sperm ability to fertilize. Some of them are reviewed here, sperm motility, block to polyspermy, chemioattraction, sperm competition for fertilization. Old and new data are reported, as for example the new notions on sperm motility derived from site directed mutagenesis in rodents, the new notions on the odour receptors in mammalian sperm attraction and new notions on sperm competition, which is variable in different species.

Amino Acid Sequence↗
PubMed2003

Unsuspected residual disease at the resection margin after surgery for lung cancer: fate of patients after long-term follow-up.

OBJECTIVE: This retrospective study evaluates the survival impact of the residual margin disease after bronchial resection for cancer and suggests tactics in cases of microresidual disease. METHODS: Between March 1988 and 1998, 4530 consecutive patients underwent surgery for non-small cell lung cancer at our institution. Only incomplete resections after microscopic evaluation (R1) were included in the study. Residual tumour cells were found on the bronchial resection margins of 39 lobectomies, 12 pneumonectomies, 4 segmental resections and one bilobectomy. Histological findings were: squamous cell carcinoma in 38 cases, adenocarcinoma in 15 and large cell carcinoma in three. In all 56 cases, invasive mucosal carcinoma was found exclusively on the bronchial resection margin. Nineteen tumours were stage I; 12, stage II; 17, stage IIIa; 5, stage IIIb; and three, stage IV. Nineteen patients (59.3%) with early stage tumours (I and II) received adjuvant radiation therapy and only three chemotherapy. RESULTS: The prognosis in these cases was disease-stage related (21 and 38.4% of deaths due to the disease). Forty-one percent of the stage IIIa patients received radiation therapy and 17.6% chemotherapy: 70.6% died of tumour relapse. Forty percent of the stage IIIb patients received radiation therapy and 20% chemotherapy: 60% died of disease progression. All of the stage IV patients died within 3 months from surgical resection. At the end of the study, 21 patients were alive after an interval of 22-142 months (18 in stage I or II). The 10-year actuarial survival rate was 44%. The percentage survival for stage IIIa was 16.8, after 10 years, and fell to 45 months for stage IIIb. CONCLUSIONS: The prognosis of our stage I or II patients with microresidual tumour on the bronchial resection margin (R1) was similar to that of the patients in the same disease stage, whose resection was microscopically radical (R0) and the same was true of the patients in stage III. In patients with residual tumour cells on the bronchial stump we did not observe worsened long-term survivals.

Adenocarcinoma↗
PubMed2003

The difficult approach to neoplastic superior vena cava syndrome: surgical option.

AIM: Superior vena cava syndrome is a dramatic event that can be cured in specialized centers. METHODS: Between 1989 and 1995 6 patients with superior vena cava syndrome underwent surgical treatment for thoracic tumors. In all cases the vena was restricted by a neoplastic sleeve. A median sternotomy was performed in all cases. Two patients received an associated right anterolateral thoracotomy to obtain good surgical exposure for tumor resection and grafting. A 12 mm diameter polytetrafluoroethylene graft was inserted in all cases. The tumor resection was radical in 4 cases (2 thymic carcinomas, 2 malignant germ cell tumors) and palliative in 2 (1 non-small cell lung cancer and 1 mediastinal fibrosis). RESULTS: We had no in-hospital mortality. All patients had immediate relief of obstruction after by-pass. Three patients were alive without disease at the end of follow-up (40-96 mo), one patient died of postoperative complications after 4 mo, 2 patients died of disease after 4 and 12 mo. CONCLUSION: PTFE by-pass graft for treatment of the obstructed SVC relieves SVC syndrome and has good medium term patency.

Adult↗
PubMed2002

Clinical and pathologic predictors of survival in patients with thymic tumors.

BACKGROUND: The aim of this study is to evaluate the impact of thymectomy in patients with thymic neoplasms and to identify clinical and histopathological factors associated with improved long-term outcome of surgery. METHODS: We treated 74 patients between February 1987 and July 1993. There were 29 total and 36 simple thymectomies. These last cases, all non-myasthenic, had benign thymomas (n=30) but 6 had thymic carcinomas. Nine tumors were no-resected (5 thymomas and 4 thymic carcinomas). Minimum follow-up by Department of Thoracic Surgery Istituto Nazionale Tumori was 60 months after thymectomy. We divided the specimens according to Marino and Muller-Hermelink's classification: 54 thymomas, 18 thymic carcinomas and 2 no-diagnosis specify thymomas. There were 53 stage I, 1 stage II, 13 stage III, 5 stage IVa and 2 stage IVb according to Masaoka. RESULTS: Forty-six patients with treated thymoma were alive without disease at the end of follow-up, the remaining 8 died from recurrence in 6, a new tumor in 1 and a heart attack in the last. Of 18 thymic carcinomas 9 were alive at the end of follow-up (1 with recurrence), only 4 dead from recurrence. The actuarial survival of patients with thymomas was 88.5% at 5 years, (73.6% in cortical type, 85.7% in medullary type, 93.9% in mixed type, 100% in predominantly cortical type). Myasthenia gravis didn't influence the survival: 87.3 (no MG) vs 90%. Advanced stage thymomas significantly increased the risk of death from early stage I: 32.4 vs 100% at 5 years. In thymic carcinoma patients with well-differentiated thymic carcinoma (WDTC) died less than others: the actuarial probability of survival at 5 years was 90 vs 68%. CONCLUSIONS: Thymectomy was the best treatment to long term outcome. In our experience, survival was related to histotype and to local extension of tumor.

Adult↗
PubMed2002

Lack of amplification phenomena of ribosomal RNA genes in sea urchin.

Careful quantitative analyses by spot hybridization to homologous probes demonstrate that no rDNA amplification occurs during Paracentrotus lividus oogenesis. The same approach was used to measure the copy number of the genes involved in ribosome biogenesis. Surprisingly, differently from the organisms in which the lack of rDNA amplification phenomena was observed, a very low number of constitutive rDNA repeats was found in this organism.

Animals↗
PubMed2001

A constitutive 70 kDa heat-shock protein is localized on the fibres of spindles and asters at metaphase in an ATP-dependent manner: a new chaperone role is proposed.

In the present study, double immunofluorescence and immunoblot analysis have been used to show that centrosomes, isolated from Paracentrotus lividus sea urchin embryos at the first mitotic metaphase, contain the constitutive chaperone, heat-shock protein (HSP) 70. More specifically, we demonstrate that centrosomes contain only the HSP70-d isoform, which is one of the four isoforms identified in P. lividus. We also provide evidence that p34(cell division control kinase-2) and t complex polypeptide-1 (TCP-1) alpha, a subunit of the TCP-1 complex, are localized on the centrosomes. Furthermore, inhibition of TCP-1 in vivo, via microinjecting an anti-(TCP-1 alpha) antibody into P. lividus eggs before fertilization, either impaired mitosis or induced severe malformations in more than 50% of embryos. In addition, we have isolated the whole mitotic apparatus and shown that HSP70 localizes on the fibres of spindles and asters, and binds them in an ATP-dependent manner. These observations suggest that HSP70 has a chaperone role in assisting the TCP-1 complex in tubulin folding, when localized on centrosomes, and during the assembling and disassembling of the mitotic apparatus, when localized on the fibres of spindles and asters.

Adenosine Triphosphate↗
PubMed2001

Conserved cellular and molecular mechanisms in development.

This review discusses examples of conserved cellular and molecular mechansims in development, including the pathway of signal transduction between the photoreceptors R8 and R7 in Drosophila, which is compared to vulval induction in Caenorhabditis elegans. The Wg pathway in Drosophila is compared, first, to the Wnt pathway in dorsal mesoderm specification in Xenopus: second, to the same pathway in sea urchins; third, to the equivalent in the mom cascade of C. elegans; and finally, to parts of the equivalent pathway in Dictyostelium discoideum. The conserved expression of some hox genes in vertebrate limb buds and in the heads or tails of several invertebrate and vertebrate embryos is also illustrated. Two further examples show the contrast between BMP4 and the proteins Noggin, Chordin, Follistatin and Gremlin. Another example concerns the binding of proteins to the 3'UTRs of several messages which inhibits their translation in Drosophila and C. elegans. The final example illustrates the selective transfer of transcription factors to nuclei in Drosophila and C. elegans.

Animals↗
PubMed2001

Quantitative and ultrastructural analysis of the chondriome in ovogenesis and embryogenesis of the sea urchin Paracentrotus lividus. 2. Growth and proliferation of mitochondria in embryogenesis.

The dynamics of structural changes of the chondriome in the early development of the sea urchin Paracentrotus lividus was studied. Mature eggs and embryos at various stages of cleavage were used for quantitative and ultrastructural analysis based on computerized 3D reconstruction from serial ultrathin sections. The following structural transformations of the chondriome were shown to occur in the course of embryogenesis: (i) 15 min after fertilization, mitochondrial clusters disintegrate, and mitochondrial division is induced. At the stage of two blastomeres the population of mitochondria increases twofold; (ii) the mitochondria divide by means of the contraction of both outer and inner membranes. The forming furrow divides the "parental" mitochondrion into two equal "daughter" parts; (iii) at the four-cell stage the division ceases, and mitochondria start to grow, so that the mitochondrial length increases; (iv) cell differentiation further stimulates elongation of rod-shaped mitochondria, and the ratio of rod-shaped to spherical mitochondria changes; (v) in an unfertilised egg, the mitochondria are in a condensed form; after fertilisation all the mitochondria acquire a conventional form. Modern concepts of chondriome proliferation in eukaryotic cells are discussed.

Animals↗
PubMed2001

Noncanonical structural-functional organization of nucleoli in maturing oocytes of sea urchin Paracentrotus lividus.

The dynamics of structural and functional organization of the nucleolus in the oocytes of P. lividus is described. At the late stages of oogenesis the nucleolus is composed of two main components, namely the peripheral zone (PZ) and the central zone (CZ) which are spatially separated. This two-component structure of the nucleolus is formed, at early stages of oogenesis, by stepwise segregation of the fibro-granular component and by its migration to the nucleolar periphery. Absence of morphologically distinct fibrillar centers and dense fibrillar component in nucleoli of both somatic cells and oocytes makes it possible to classify the nucleoli of P. lividus as 'noncanonical' type. Based on detailed morphological and cytochemical analysis the following molecular interpretation of nucleolar ultrastructure in oocytes of P. lividus is proposed: 1) the PZ, containing RNP-positive granules 15 nm in size, but lacking Ag-NOR proteins and BrU incorporation, can be considered a structural equivalent of the granular component of 'typical' nucleoli; 2) the CZ, which is the site of incorporation of RNA precursors, contains intranuclear DNA, RNP-fibers and accumulates Ag-NOR proteins, corresponds to both FC and DFC of 'typical' nucleoli; 3) nucleolar growth during oogenesis, leading to the 1000-fold increase of nucleolar volume, seems to be correlated with the stockpiling of nonfunctioning mature preribosomal particles which will be utilized during embryogenesis.

Animals↗
PubMed2001

Division and motility of mitochondria in sea urchin embryogenesis.

The influence of actin and tubulin cytoskeletons on the shape, division and on intracellular motility of mitochondria was studied in eggs and embryos of the sea urchin Paracentrotus lividus. Depolymerization of actin filaments and microtubules was induced by specific inhibitors as cytochalasin D (CytD) and colcemid respectively. The quantitative analysis of the mitochondrial population shows that: 1) the chondriome of an egg consists of numerous (about 15,000) discrete mitochondrial clusters uniformly distributed throughout the cytoplasm, each cluster containing 10 to 20 mitochondria of spherical or rod-like shape; 2) fertilization induces cluster break-down and mitochondrial division within 15 min after insemination; at 100 min after fertilization mitochondria become evenly distributed throughout the cytoplasm and the population of mitochondria doubles; 3) in embryos obtained from eggs inseminated after treatment with CytD clusters break-down and mitochondriokinesis are blocked; 4) when added 15 min after insemination, CytD uncouples coordinated invagination of outer and inner membranes in dividing mitochondria thus bringing about abnormal mitochondriokinesis; 5) the treatment of the eggs with colcemid does not affect the normal embryonic mitochondriokinesis.

Actins↗
PubMed2000

[Ankle impingement syndrome].

PURPOSE: The ankle impingement syndrome depends on many factors (fiber or bone production changes) manifested with pain and limited range of movement of the tibiotarsal joint. We tried to classify the various causes and sites of impingement syndromes with MRI. MATERIALS AND METHODS: A cohort of 42 selected patients underwent a 2-year orthopedic follow-up. All patients were examined with MRI using both a low field permanent dedicated magnet at 0.2 Tesla (Artoscan, Esaote Biomedica, Genoa, Italy) and a high field General Electric unit at 1.0 T; sequences and views were chosen according to the condition studied. Gd-DTPA was administered in 26/42 patients. All patients underwent arthroscopy. RESULTS: Twenty-one patients had positive symptoms in the anterolateral region of the ankle and 14 of them had lateral changes. In 13 patients we found fibrous tissue (meniscoid lesion) or hypertrophy of the synovial tissue. An intra-articular body was observed in one patient. An osteophyte was found in 5 patients at the level of the anterior margin of the tibia, with the presence of reactive synovial tissue. Three of 18 patients with posterior pain had a traumatic injury of the posterior exterior tubercle of the astragalus, 7 had a fracture of the os trigonum and 2 had small sclerotic foci formations in calceneal site; chondropathy with sclerosis of subchondral bone was diagnosed in 2 patients. Posterior bone impingement was observed in the remaining 4 patients. Two patients had synovial impingement in posterolateral site. A posterior plica synovialis was seen in 1 patient. Fibrotic-scar tissue was observed in one case, in the subtalus region (impingement synovialis subtalaris). The administration of intra-articular Gd-DTPA provided better definition of the fibrous tissue and the intra-articular free bodies. Modest vascular enhancement of the tissues was seen in 9 of 8 patients receiving the contrast agent. In the other two cases, where signal tissue was low, no signal enhancement was observed after the contrast agent administration. DISCUSSION: Based on integrated MR, clinical and arthroscopic findings we classified tibiotarsal joint impingement syndromes into three types, namely: 1) bone impingement; 2) fibrous impingement where both site and grade are considered; 3) impingement synovialis subtalaris. CONCLUSIONS: MRI appears to be a fundamental diagnostic imaging tool in depicting and detailing the various patterns and sites of the impingement syndrome of the tibiotarsal joint thus allowing an objective classification.

Adult↗
PubMed1999

Constitutive hsp70 is essential to mitosis during early cleavage of Paracentrotus lividus embryos: the blockage of constitutive hsp70 impairs mitosis.

Localization of constitutive hsp70 in eggs and early embryos of sea urchin Paracentrotus lividus is shown by means of in situ immunostaining. An accumulation of this protein is shown in the mitotic structures (asters, spindles and centrosomes). Microinjection of anti-hsp70 antibodies into eggs causes impairment of formation of mitotic structures and of cell division. This impairment goes from a complete mitotic block, to irregular mitotic apparatus formation with irregular cleavage, depending upon the antibody concentration. The localization of hsp70 after antibody microinjection is also described. Blockage of mitotic apparatus formation by nocodazole also blocks the concentration of hsp70 molecules observed in nontreated eggs. That the constitutive hsp70 plays a role in sea urchin mitosis is indicated.

Animals↗
PubMed1999

Studies on heat shock proteins in sea urchin development.

Work on stress proteins in sea urchin embryos carried out over the last 20 years is reviewed and the following major results are described. Entire sea urchin embryos, if subjected to a rise in temperature at any postblastular stage undergo a wave of heat shock protein (hsp) synthesis and survive. If subjected to the same rise between fertilization and blastula formation, they are not yet able to synthesize hsp and die. Four clones coding for the major hsp, hsp70, have been isolated and sequenced; evidence for the existence of a heat shock factor has been provided, and a mechanism for the developmental regulation of hsp synthesis discussed. Intraembryonic and intracellular hsp location has been described; and a mechanism for achievement of thermotolerance proposed. A chaperonine role for a constitutive mitochondrial hsp56 has been suggested, as well as a role for the constitutive hsp70 in cell division. Heat shock, if preceded by 12-O-tetradecanoylphorbol-12-acetate (TPA) treatment causes apoptosis.

Animals↗
PubMed1998

Effect of the IMPase inhibitor L690,330 on sea urchin development.

A variety of concentrations of the IMPase inhibitor L690,330 were added to sea urchin embryos. Immediate arrest of development was obtained for concentrations from 7.5 mm on. Concentrations lower than 3.5 mm permitted gastrulation but inhibited skeletogenesis and disturbed elongation along the animal-vegetal axis. The latter results are similar to those obtained by counteracting lithium effect with myoinositol, which are suggested to be due to partial relief of IMPase inhibition.

5'-Nucleotidase↗