PubMed Health⌕ Search

Biomedical subjects

N Pushparaj

Publications and source records attributed to N Pushparaj.

12 recordsLinked to original sources

Trabecular architecture in iliac crest bone biopsies: infra-individual variability in structural parameters and changes with age.

A histomorphometric study was conducted on bilateral iliac crest samples obtained at autopsy from 27 subjects who had died suddenly. Six parameters related to cancellous bone structure were measured: bone volume (BV/TV), surface density (BS/TV), surface/volume ratio (BS/BV), trabecular thickness (Tb.Th.), trabecular number (Tb.N), and trabecular separation (Tb.Sp). There were no significant differences between right and left sides in the mean values for each parameter. However, when subjects were considered individually, there was a substantial difference in the majority of cases for all parameters. The intra-individual variation (IIV) was calculated for each subject as the percentage deviation from the mean for the two sides. There was a wide range in IIV (0.05-30.27%) with a mean value of approximately 11.5% for each parameter. In males the mean IIV ranged from 9 to 11% and from 14 to 16% in females. The IIV in BV/TV was positively correlated with age. Data generated on a subsample of 15 males were used to predict patient group sizes required to detect minimum significant differences in studies involving repeat biopsies. Sample sizes of 32, 16, and 8 patients would be required for relative increments in BV/TV of 29, 36, and 46%, respectively, to be statistically significant. Tb.Sp increased significantly with age but there was no significant change in Tb.Th. This supports the view that bone loss with aging occurs primarily through a mechanism involving complete disappearance of individual trabecular plates.

Adult↗

Nonepithelial tumors of the nasal cavity, paranasal sinuses, and nasopharynx. A clinicopathologic study. XIV: Chordomas.

Twenty cases of a rare tumor, chordoma involving the nasal cavity, paranasal sinuses, or nasopharynx, are reported. Patients most often had localized headache, nasal obstruction, decreased hearing, or symptoms related to cranial nerve involvement, especially diplopia. A mass bulging into the nasopharynx, posterior nasal cavity, or pharynx was found on physical examination in 13 of these 20 patients, and in another 6 patients on radiologic examination. Paralysis of one or more cranial nerves was identified in the majority of patients who had tumors involving the upper nasopharynx. On radiologic examination, bone destruction was frequently identified in the clivus and sphenoid areas, and less commonly in the cervical vertebrae. Each patient had biopsy-proven tumor in the nasopharynx or sphenoid areas. Patients usually were treated by combinations of surgery and radiotherapy, in some cases leading to prolonged periods of apparent tumor control. Radiotherapy frequently resulted in regression of symptoms, sometimes lasting many months or years. A few tumors that involved mainly the lower nasopharynx were more amenable to surgical resection, in one case leading to apparent tumor control. In those cases with adequate follow-up information, most patients had either died of their disease or were living with recurrent or persistent inoperable tumor. Some patients lived for many months or years between recurrences or with known tumor, indicating that chordomas often are slowly growing neoplasms. The histologic features of these chordomas are described and illustrated, and the histopathologic differential diagnosis is discussed.

Adolescent↗

Endocrine changes associated with the human aging process: II. Effect of age on the number and size of thyrotropin immunoreactive cells in the human pituitary.

The thyrotropin immunoreactive cells in the pituitaries of 40 patients of varying ages were quantified after immunocytochemical staining. Thyrotroph hypertrophy and relative hyperplasia were both present in aged pituitaries. No consistent relation with the histologic features of the thyroid or adrenal, or with the cause of death, was demonstrable.

Adolescent↗

Endocrine changes associated with the human aging process: III. Effect of age on the number of calcitonin immunoreactive cells in the thyroid gland.

The thyroid glands obtained at autopsy from 60 patients ranging in age from 16 to 89 years were immunostained for calcitonin (CT) by the peroxidase-antiperoxidase procedure. The numbers of CT immunoreactive cells identified were 0.99 +/- 1.07/mm2 in the young patients (16 to 39 years of age), 0.99 +/- 1.46/mm2 in the middle-aged (40 to 59 years of age), and 2.97 +/- 3.69/mm2 in the elderly (60 years of age and older). The results were not statistically significant because of the large standard deviation. The CT immunoreactive cells tended to aggregate in clusters in a pattern similar to that seen in C-cell nodules in older persons.

Adenoma↗

Nonepithelial tumors of the nasal cavity, paranasal sinuses, and nasopharynx. A clinicopathologic study. XIII: Meningiomas.

Twelve cases of meningiomas involving the nasal cavity and paranasal sinuses are reported. Meningiomas only rarely involve the upper respiratory tract; these 12 cases were found among the 566,000 surgical pathology cases that have been studied in this laboratory. In this series, five meningiomas probably arose in the cranial cavity and secondarily extended into the nasal cavity and paranasal sinuses. Because radiographs demonstrated hyperostosis or bone destruction, three other tumors could have involved the cranial cavity, but this was never proven. In two other cases, the meningiomas appeared to involve only extracranial tissues and thus probably were primary extracranial lesions. (The data available in two other cases were insufficient to assess the possibility of intracranial involvement). These patients clinically had nonspecific signs and symptoms similar to those produced by other types of neoplasms growing in the upper respiratory tract. The tumor involved the sphenoid area in seven cases, the nasal cavity in six, the maxilla in five, the ethmoid sinus in four, and the frontal sinus in one. The diagnosis was first established when biopsy material was examined, although in several cases the presence of meningioma was first suggested on radiographic examination. Treatment depended upon the size and location of the tumor. In some cases, surgical resection appeared to control the lesion. These tumors did not appear to respond well to radiotherapy. The histologic differential diagnosis is discussed.

Adult↗

The effect of age on the number of pituitary cells immunoreactive to growth hormone and prolactin.

The results of a combined immunocytochemical, morphometric, and clinicopathologic analysis of growth-hormone-producing and prolactin-producing pituitary cells in 28 subjects ranging in age from 16 to 90 are reported. There was a significant age-related decline in the number and size of growth-hormone-producing cells, which was most marked in the transition from youth to middle age. There was also a significant age-related decline in the number of pituitary parenchymal cells but not in pituitary weight. Prolactin cells did not show a significant decline in number with age.

Adolescent↗

Diseases associated with aging.

Friese has recently presented a graph of the demographics of aging, indicating that the number of people over 65 in 1990 will approach 21 million, or 15% of the population. The life expectancy of men will soon approach that of women (74 to 75 years). As cancer, heart disease, and stroke are conquered, longevity will increase by less than 12 years. The older population will have increasingly diminished physical and mental capacity, not necessarily associated with specific disease processes, but rather resulting from a generalized cellular and extracellular deterioration, particularly affecting the homeostatic control mechanisms of the central nervous, neuroendocrine, and immune systems. They will require increased protection from the environmental insults with which they could cope more easily at an earlier age. Their treatment will have to be individually adjusted depending on the combination of lesions they display. The patient's socioeconomic status, family support structure, and general psychological profile play significant roles in their longevity and terminal illness.

Adolescent↗

Olfactory neuroblastoma. Response to combination chemotherapy.

A patient with olfactory neuroblastoma who had bone marrow metastasis at the time of diagnosis is presented. Previous therapy for this disease consisted of surgery and radiation. There is limited information relating to the efficacy of chemotherapy. Our patient was treated with combination chemotherapy (dacarbazine [DTIC-Dome], cyclophosphamide [Cytoxan], doxorubicin hydrochloride [Adriamycin], and vincristine sulfate [Oncovin]) and radiation to the primary site. Objective findings, more than two years after diagnosis, support a good partial response. Although a 50%, five-year survival time has been reported, the five-year cure rate is 18%. This report suggests that the role of combination chemotherapy should be further evaluated in certain patients with olfactory neuroblastoma.

Adult↗