Biomedical subjects

M Crosato

Publications and source records attributed to M Crosato.

At least 19 recordsLinked to original sources

PubMed2003

A neovascularized organoid derived from retrovirally engineered bone marrow stroma leads to prolonged in vivo systemic delivery of erythropoietin in nonmyeloablated, immunocompetent mice.

Marrow stromal cells (MSCs) are postnatal progenitor cells that can be easily cultured ex vivo to large amounts. This feature is attractive for cell therapy applications where genetically engineered MSCs could serve as an autologous cellular vehicle for the delivery of therapeutic proteins. The usefulness of MSCs in transgenic cell therapy will rely upon their potential to engraft in nonmyeloablated, immunocompetent recipients. Further, the ability to deliver MSCs subcutaneously - as opposed to intravenous or intraperitoneal infusions - would enhance safety by providing an easily accessible, and retrievable, artificial subcutaneous implant in a clinical setting. To test this hypothesis, MSCs were retrovirally engineered to secrete mouse erythropoietin (Epo) and their effect was ascertained in nonmyeloablated syngeneic mice. Epo-secreting MSCs when administered as 'free' cells by subcutaneous or intraperitoneal injection, at the same cell dose, led to a significant - yet temporary - hematocrit increase to over 70% for 55+/-13 days. In contrast, in mice implanted subcutaneously with Matrigel trade mark -embedded MSCs, the hematocrit persisted at levels >80% for over 110 days in four of six mice (P<0.05 logrank). Moreover, Epo-secreting MSCs mixed in Matrigel elicited and directly participated in blood vessel formation de novo reflecting their mesenchymal plasticity. MSCs embedded in human-compatible bovine collagen matrix also led to a hematocrit >70% for 75+/-8.9 days. In conclusion, matrix-embedded MSCs will spontaneously form a neovascularized organoid that supports the release of a soluble plasma protein directly into the bloodstream for a sustained pharmacological effect in nonmyeloablated recipients.

Animals↗

PubMed2002

Active versus borderline myocarditis: clinicopathological correlates and prognostic implications.

OBJECTIVE: To compare active (AM) with borderline (BM) myocarditis to verify whether the pathological distinction between the two forms may help to identify patients with different clinical and haemodynamic characteristics and to aid prognosis. MATERIALS: Myocarditis was diagnosed in 56 patients on endomyocardial biopsy (EMB) within one year from clinical onset of the disease between 1991 and 1998. Fourteen patients were excluded because of a lack of adequate and complete information. EMBs and clinical records of the 42 remaining patients were reviewed. Immunohistochemistry on bioptic samples was regularly performed. Polymerase chain reaction (PCR) for a panel of viruses was performed in 23 patients (55%). Clinicopathological correlations were calculated. RESULTS: The histological diagnosis was AM in 26 patients (62%) and BM in 16 (38%). Significant differences were found in the following parameters: presence of left bundle branch block on ECG (AM 2 (8%) v BM 5 (31%), p = 0.05); left ventricular volume on echocardiogram (mean (SD) AM 90 (42) ml/m(2) v BM 128 (50) ml/m(2), p = 0.002); mass to volume ratio (AM 1.0 (0) v BM 0.8 (0.1), p = 0.03); time interval between clinical onset of the disease and EMB (AM 40 (55) v BM 90 (93) days, p = 0.04); and degree of inflammatory infiltrates, scored on a scale of 0 to 3 (AM 1.65 (0.8) v BM 0.85 (0.3), p = 0.004). In 6 of 15 patients (40%) with AM and in 2 of 8 (25%) with BM, a viral genome was detected by PCR (NS). At follow up, no differences in death or heart transplantation were detected between the two forms (AM 4 patients (15%) v BM 2 patients (12.5%)). Three of eight PCR positive patients (37.5%) and 1 of 15 virus negative patients (7%) died or underwent heart transplantation. CONCLUSIONS: BM seems to encompass inflammatory forms with a less aggressive inflammatory infiltrate evolving towards left ventricular dilatation. The term "chronic myocarditis" seems to be more appropriate. The absence of myocyte necrosis does not predict a more favourable prognosis, whereas the absence of a viral genome seems to predict it.

Adolescent↗

PubMed2001

Expression of p21Waf1/Cip1 and cyclin D1 is increased in butyrate-resistant HeLa cells.

Sodium butyrate induced cell cycle arrest in mammalian cells through an increase in p21Waf1/Cip1, although another study showed that this arrest is related to pRB signaling. We isolated variants of HeLa cells adapted to growth in 5 mm butyrate. One of these variants, clone 5.1, constitutively expressed elevated levels of p21Waf1/Cip1 when incubated in regular growth medium and in the presence of butyrate. Despite this elevated level of p21Waf1/Cip1, the cells continue to proliferate, albeit at a slower rate than parental HeLa cells. Western blot analyses showed that other cell cycle regulatory proteins were not up-regulated to compensate for the elevated expression of p21Waf1/Cip1. However, cyclin D1 was down-regulated by butyrate in HeLa cells but not in clone 5.1. We conclude that continued expression of cyclin D1 allowed clone 5.1 to grow in the presence of butyrate and elevated levels of p21Waf1/Cip1.

Blotting, Western↗

PubMed1999

HDAC4, a human histone deacetylase related to yeast HDA1, is a transcriptional corepressor.

Histone acetylation plays an important role in regulating chromatin structure and thus gene expression. Here we describe the functional characterization of HDAC4, a human histone deacetylase whose C-terminal part displays significant sequence similarity to the deacetylase domain of yeast HDA1. HDAC4 is expressed in various adult human tissues, and its gene is located at chromosome band 2q37. HDAC4 possesses histone deacetylase activity intrinsic to its C-terminal domain. When tethered to a promoter, HDAC4 represses transcription through two independent repression domains, with repression domain 1 consisting of the N-terminal 208 residues and repression domain 2 containing the deacetylase domain. Through a small region located at its N-terminal domain, HDAC4 interacts with the MADS-box transcription factor MEF2C. Furthermore, HDAC4 and MEF2C individually upregulate but together downmodulate c-jun promoter activity. These results suggest that HDAC4 interacts with transcription factors such as MEF2C to negatively regulate gene expression.

Amino Acid Sequence↗

PubMed1997

Processing of amyloid precursor protein in human primary neuron and astrocyte cultures.

Increased production of amyloid beta peptide (A beta) is highly suspected to play a major role in Alzheimer's disease (AD) pathogenesis. Because A beta deposits in AD senile plaques appear uniquely in the brain and are fairly restricted to humans, we assessed amyloid precursor protein (APP) metabolism in primary cultures of the cell types associated with AD senile plaques: neurons, astrocytes, and microglia. We find that neurons secrete 40% of newly synthesized APP, whereas glia secrete only 10%. Neuronal and astrocytic APP processing generates five C-terminal fragments similar to those observed in human adult brain, of which the most amyloidogenic higher-molecular-weight fragments are more abundant. The level of amyloidogenic 4-kDa A beta exceeds that of nonamyloidogenic 3-kDa A beta in both neurons and astrocytes. In contrast, microglia make more of the smallest C-terminal fragment and no detectable A beta. We conclude that human neurons and astrocytes generate higher levels of amyloidogenic fragments than microglia and favor amyloidogenic processing compared with previously studied culture systems. Therefore, we propose that the higher amyloidogenic processing of APP in neurons and astrocytes, combined with the extended lifespan of individuals, likely promotes AD pathology in aging humans.

Amyloid beta-Protein Precursor↗

PubMed1990

[A case of familial bilateral polycystic kidney].

The paper describes a case of bilateral polycystic kidney in a 14-year-old whose father and 3 brothers are also affected by bilateral renal cystic dysplasia (as is a paternal aunt), while a paternal uncle is affected by constant hematuria with no ultrasound signs of renal cystic dysplasia. The case in question is an adult type of dominant autosomal polycystic renal dysplasia, affecting all the males in the family and also a female within the family nucleus. The case is described in the light of the most recent reports on the subject and the problem of prevention is also discussed.

Adolescent↗

PubMed1989

[Remarks on a clinical case of partial carbamyl phosphate synthetase deficiency].

A preliminary undiagnosed case of partial carbamyl-phosphate-synthetase deficiency in a 14 year old patient is described. This extremely rare metabolic disorder is unlikely to produce clinical symptoms at such an advanced age. Details are given of the clinical picture, the diagnosis (by liver biopsy and post mortem liver examination) and the attempts at treatment.

Adolescent↗

PubMed1989

[Effect of cimetropium bromide in the treatment of colic in the first 3 months of life. Randomized study].

UNLABELLED: 20% of unweaned children aged below three months suffer from so-called gaseous colic. The effectiveness and tolerance of an antimuscarinic drug with high spasmolytic activity on the smooth visceral musculature, cimetropium bromide, has been evaluated, excluding cases of intolerance to cow's milk and other pathologies. 40 random patients of both sexes of average age 4.4 weeks (symptoms lasting for one week with crying fits lasting for more than 90 minutes consecutively, on at least 3 days a week) split into two groups of 20 patients each were studied. TREATMENT: A) 1.2 mg/kg 1 hour before bottle; B) 2.0 mg/kg 1 hour before bottle. Speedy reduction in the number of crying episodes (Group A: from 2.8 +/- 0.3 to 0.1 +/- 0.1; Group B: from 2.8 +/- 0.4 to 0.6 +/- 0.4; differences n.s.) and in their duration (Group A: 99 min +/- 10 min to 5 min +/- 3 min; Group B: from 121 min +/- 11 min to 15 min +/- 9 min; differences n.s.). The pharmacological treatment was considered: Group A: very good in 75% of cases; Group B: very good in 70% of cases. In Group B 4 episodes of stypsis occurred and these resolved immediately upon suspension of the drug. Given the equal effectiveness and better tolerance, the use of cimetropium bromide is recommended at the lower dosage.

Colic↗

PubMed1988