Search PubMed⌕ Search

Biomedical subjects

C A Curcio

Publications and source records attributed to C A Curcio.

48 records · Page 3Linked to original sources

Stability of neuron number in cortical barrels of aging mice.

The question of whether age-related neuron loss occurs in the cerebral cortex of rodents, as it apparently does in humans, has not been directly answered by previous studies. The barrel, a discrete morphological and functional unit in rodent somatosensory cortex, is a favorable system in which to address the problem of neuron loss during senescence. The numerical density and absolute number of neurons as well as barrel volume were determined from a computer-assisted three-dimensional reconstruction of thick (100 microns) and semithin (1 micron) sections through a single barrel, C3, from inbred mice (C57Bl/6NNia) at 4, 12, 22, 26, 30, and 33 months of age. The number and density of neuron and glial cells and the volume of the barrel did not change significantly with age. These data indicate that neuron loss is not a universal phenomenon in senescence and that there may be significant species differences in the aging of laboratory rodents and humans.

Aging↗

A computer system for combined neuronal mapping and morphometry.

A computer system has been developed which allows both mapping and planimetry of histological preparations. Data consist of cytoarchitectonic boundaries defined in low-power micrographs of thick sections, and nuclear and vascular profiles defined in high-power micrographs of semi-thin sections taken from the original thick tissue, and landmarks common to both. Data from these different preparations and magnifications are entered into the computer on a digitizing tablet and are stored as points in a real-world coordinate system, along with profile labels, landmarks for alignment purposes, and section depth. Subsequent programs determine parameters such as area and perimeter for each profile, as well as its geometric center and relationship to the cytoarchitectonic boundary. This mapping parameter allows morphometric analysis of profiles as a function of their position. Other programs allow display and manipulation of data in 3 dimensions, cell counts, and stereology. Data acquisition is done in the laboratory, using a micro-computer; analysis and display are done on a large time-sharing computer connected to the small machine by a telephone interface.

Animals↗

[The aorto-coronary by-pass. Personal clinical experience (author's transl)].

The surgical treatment of coronary artery disease still remains controversial, despite the fact that the surgical indications are widely recognized and so the efficacy of the aortocoronary bypass in relieving angina and in improving the prognosis of the patients with left mainstem lesions. However, one gets the impression that the criteria for surgery not always are correctly applied, with the consequence that the bypass is often performed on patients that could still benefit from proper medical treatment. At Groote Schuur Hospital, during the period 1976-78, we have bypassed a total of 395 coronary arteries in 204 patients. All the patients were in NYHA class III and IV. The peculiarity of this rather small series is based on the conservatism of the selection criteria, the operation being offered only to candidates with a very long history of angina uncontrolled by adequate medical treatment. The early mortality rate has been 1.47%, the late mortality rate 3.5% and the perioperative infarction rate 10.8%. All the patients have been followed up for 12-48 months (mean follow up 30.3 months). 80% of the patients returned in class I and 13.5% in class II. 80 out of 112 patients operated during 1976-77 have had routine coronary angiography one year post-surgery: the graft patency rate in this group has been 71%. The majority of the obstructed grafts were related to small vessels of 1 mm in diameter. On the basis of these clinical results we conclude that no controversy is justified once and adequate trial with proper medical treatment has already failed.

Angina Pectoris↗

Calcification of glutaraldehyde-preserved porcine xenografts in young patients.

In a series of 568 patients with glutaraldehyde-preserved porcine xenografts followed for up to 3 1/2 years, calcification and stenosis of the xenograft has proved to be an important cause of valve failure. We have seen this complication only in children and adolescents. Seven of 54 patients under 16 years of age at the time of initial operation have required reoperation for calcification and prosthetic stenosis. Three patients who died had calcified, stenosed prosthesis at autopsy. The calcification has involved all of the cusps of the affected prostheses, and the calcified area often was enclosed by a superficial layer of noncalcified cuspidal tissue. We no longer insert xenograft valves in young patients.

Adolescent↗

[Cardiac valve replacement in patients over 70 years (author's transl)].

39 patients aged 70 years and over, 24 males and 15 females underwent valve replacement at Groote Schuur Hospital between 1969 and 1979. 30 patients were affected from aortic valve disease, 6 from mitral valve disease and 3 from mixed mitral and aortic valve disease. The rate of postoperative complications have remained low, and specific complications for this age group have not been observed. 38 patients have been followed up for 1-120 months (mean 30 months). The majority of patients have experienced a remarkable functional improvement. The findings indicate that valve surgery can be performed in the older age group with the same low risk observed in the younger patients.

Age Factors↗

Lymphoma of the heart as an unusual cause of pericardial effusion. A case report.

A patient presented with cardiac tamponade which resolved after aspiration. Laboratory examination of the pericardial fluid and a biopsy specimen of the pericardium were diagnostically unhelpful. Surgical exploration revealed the presence of an extensive lymphoma involving the cavity and myocardium of the right atrium and right ventricle, with widespread systemic involvement. The initial response to surgical relief of obstruction to blood flow as satisfactory, and to date chemotherapy has been successful in preventing recurrence of the tumour.

Heart Atria↗

The advantage of heterotopic cardiac transplantation over orthotopic cardiac transplantation in the management of severe acute rejection.

The major problems with organ transplantation are rejection of the allograft and the side effects of antirejection therapy. This report describes the successful treatment of a patient in whom rejection of the donor heart developed 10 months after implantation. The recipient's own heart had been left intact and was able to support the circulation during the period of rejection. Indications are that the "rest" period of 10 months was beneficial to the myopathic left ventricle of the recipient's heart.

Adult↗

Stability of dendrites in cortical barrels of C57BL/6N mice between 4 and 45 months.

Qualitative and quantitative studies of dendritic parameters were conducted on Golgi-impregnated layer IV spiny stellate neurons in the posteromedial barrel subfield (PMBSF) of somatosensory cortex of the C57B1/6N mouse. Three mice each, at 4, 12, 22, 26, 30, 36 and 45 months of age were studied. No qualitative changes were observed among animals of different ages. The quantitative data indicated that dendritic length and numbers of segments remained unchanged over all ages studied.

Aging↗

Photoreceptor inner segments in monkey and human retina: mitochondrial density, optics, and regional variation.

The present work quantifies aspects of photoreceptor structure related to mitochondria, inner segment dimensions, and optical properties, as a basis for furthering our understanding of rod and cone function. Electron-microscopic analyses were performed on the retina of one stumptail macaque (Macaca arctoides) to obtain stereological measurements of ellipsoid mitochondrial density, and sizes and shapes of outer and inner segments. In addition, the distribution of mitochondria and the optical properties of human foveal cones were examined with electron microscopy and Nomarski differential interference contrast (NDIC) imaging. Mitochondria comprised 74-85% of cone ellipsoids and 54-66% of rod ellipsoids in macaque. Ellipsoid volume increased with eccentricity by 2.4-fold for rods and more than 6-fold for cones over eccentricities to 12.75 mm, while the volume of the outer segment supported by the ellipsoid was essentially constant for both rods and cones. Per unit volume of outer segment, cones contained ten times as much mitochondria as rods. In human fovea, as in the rest of the retina, most cone mitochondria were located in the distal inner segment. In the foveal center, however, there are also mitochondria in the myoid, as well as in the outer fiber, proximal to the external limiting membrane (ELM). Analyses of the optical aperture of human foveal cones, the point at which their refractive index clearly differs from the extrareceptoral space, showed that it correlated well with the location of mitochondria, except in the foveal center, where the aperture appeared proximal to the ELM. While mitochondria have an important metabolic function, we suggest that the striking differences between rods and cones in mitochondrial content are unlikely to be determined by metabolic demand alone. The numerous cone mitochondria may enhance the waveguide properties of cones, particularly in the periphery.

Animals↗