Search PubMed⌕ Search

Biomedical subjects

B Gondos

Publications and source records attributed to B Gondos.

At least 91 records · Page 5Linked to original sources
PubMedDate not supplied

Squash preparation studies of germ cells in human fetal testes.

Testes from human fetuses 21 to 41 weeks of gestation were investigated using a modified squash technique. At all of the gestational ages examined, 90 to 95% of the germ cells were in interphase. Preleptotene germ cells, which exhibited densely staining condensed clumps of chromosomes, were found in all samples studied and constituted 3 to 9% of the germ cells observed. In appearance they resembled preleptotene figures seen in the fetal ovary. Occasionally, germ cells containing slender chromosomes with a beaded appearance, but without prominent condensation, were encountered. These cells were interpreted as preleptotene germ cells in the early stages of degeneration. Germ cells in other meiotic stages were not observed in this study.

Cell Separation↗
PubMedDate not supplied

Human fetal pancreas transplants.

Human fetal pancreatic islet tissue has several advantages as a transplant source for the amelioration of insulin deficiency in patients with Type I diabetes mellitus. It is now possible to obtain viable tissue, store and ship the tissue without adverse effects on the insulin secretory capacity, and transplant either minced tissue or isolated islet-like cell clusters following digestion and culture into animal models or man. A number of centers have undertaken studies of human fetal pancreatic allografts in man. Optimal results have occurred when pooled tissue from six to 20 donors has been implanted and a number of sites have been studied. The author's own experience in four recipients who did not receive immunosuppression has documented insulin secretion for up to 1 year in the absence of an anticytoplasmic islet cell antibody response on the part of the recipients. Nevertheless, the procedure has not resulted in insulin independence for the recipients and the implanted tissue has not secreted insulin in response to a glucose-amino acid challenge in a normal physiologic pattern. Thus, human fetal pancreatic transplantation for the treatment of Type I diabetes remains an experimental approach.

Animals↗
PubMedDate not supplied

Type 2 diabetes: the epidemic of the new millennium.

The increasing prevalence of obesity, which has reached epidemic proportions, raises the likelihood that a similar increase in diabetes will follow. Linkage between the two conditions is clear. Overweight is not only an important risk factor for the development of diabetes, but also has a significant impact on progression and complications. Diagnostic criteria for the recognition of diabetes and for monitoring of the disease process will become increasingly important. The role of laboratory evaluation needs to be reassessed in light of new concepts regarding classification and diagnostic criteria. The relative utility of glucose and glycosylated protein measurements should be addressed, particularly the relationship between laboratory findings and clinical guidelines. Blood glucose monitoring depends on establishment of the threshold for diagnosis. Additional issues are bedside monitoring, the goal of noninvasive glucose sensors and targeting of therapy. The laboratory scientist is likely to play a key role in the application of advances in the detection and management of diabetes.

Diabetes Mellitus, Type 2↗
PubMedDate not supplied

Testicular changes associated with the initiation of spermatogenesis.

Testicular changes preceding and accompanying the initiation of spermatogenesis are reviewed. The complex cellular changes occurring in the developing testis are found to be particularly well defined with the use of electron microscopy. The findings suggest that electron microscopic examination may be useful in the evaluation of male infertility, especially in those cases in which clinical and laboratory findings are negative or inconclusive. The amount of tissue required is minimal and can be taken as part of the regular testicular biopsy. The additional information provided by electron microscopy can be used to clarify the observations made on routine light microscopic study and may also lead to better understanding of the pathologic changes occurring in some of the less well understood forms of male infertility.

Animals↗
PubMedDate not supplied

Cytology of cerebrospinal fluid: technical and diagnosis considerations.

The usefulness of cerebrospinal fluid cytology in the diagnosis of malignancy has been enhanced in recent years by the development of new techniques for increasing cellular yield. Micropore filters and a specially adapted cytocentrifuge have been used for this purpose with a resulting increase in cell concentration and in diagnostic accuracy. Cerbrospinal fluid examination has been found to be of particular value in the diagnosis of metastatic carcinoma, lymphomatous and leukemic involvement of the meninges and certain primary central nervous system tumors. Cytologic criteria for the differential diagnosis of the principal types of tumors encountered in cerebrospinal fluid are discussed.

Astrocytoma↗
PubMedDate not supplied

Cerebrospinal fluid cytology: diagnostic accuracy and comparison of different techniques.

Cytologic examination of cerebrospinal fluid was performed in 1,021 patients, using Nuclepore and Millipore filter techniques. Positive findings were obtained in 89 cases, including 40 with primary central nervous system tumors, 24 with metastatic tumors and 25 with leukemic or lymphomatous involvement. When correlated with histologic findings, the overall detection rate was 32.2 per cent for primary tumors, 53.3 per cent for metastatic tumors and 65.8 per cent for leukemia and lymphoma. Highest degree of accuracy in the primary tumor group was achieved with medulloblastoma (61.9 per cent). Among metastatic tumors, those originating in the lung (70 per cent) and breast (83 per cent) were the one most often detected. Comparison of the two filter techniques indicated a slightly higher detection rate when the Millipore filter was used. The reasons for this are not entirely clear, but increased cellular yield with the Millipore filter may be an important factor. The cytocentrifuge method was found to be generally inferior to either of the filter techniques in quality of cell preservation. Our findings indicate that diagnostic usefulness of cerebrospinal cytology depends on collection and preparation methods as well as the anatomic distribution and biologic behavior of the lesions.

Cerebrospinal Fluid↗
PubMedDate not supplied

Computerized reporting and follow-up of gynecologic cytology.

A system utilizing inexpensive computer hardware to produce high-quality cytology report and to provide an extensive, semi-automated follow-up system is described. Key features of the reports generated are emphasized. The system uses the Bethesda System nomenclature for reporting cytologic findings to a wide range of physicians, from general practitioners to gynecologists to subspecialists in gynecologic oncology.

Female↗
PubMedDate not supplied

Gonadal disorders in infancy and early childhood.

Disorders of gonadal development can result from chromosomal, genetic, endocrine, or structural abnormalities. The different conditions may have similar clinical features, but behavior and management will vary depending on the particular diagnosis. Disorders that appear in infancy and early childhood are often associated with ambiguous genitalia or abnormal sexual development. Distinction is made on the basis of cytogenetic, hormonal, and, when indicated, histopathologic studies. The current review groups the different abnormalities in the following categories: chromosomal and genetic disorders; structural defects; defective endocrine function; excessive endocrine activity. The principal conditions found in these categories are discussed in terms of pathogenesis and laboratory procedures required to establish a precise diagnosis.

Endocrine System Diseases↗
PubMedDate not supplied

Cytologic screening for cervical cancer in southern Iran.

In an 11 year study of cytologic examinations from the southern part of Iran with a 99 percent Moslem population, the prevalence rate of invasive cervical carcinomas in 35,222 women screened for the first time was 2.3 per 1,000 examinations. With the initiation of a mass screening program begun in 1974, the rates of CIS and moderate and severe dysplasia rose threefold. These findings indicate that carcinoma of the cervix is an important problem in Iran, despite previous reports of the contrary. There is, thus, a clear need for encouraging and expanding the mass screening program which has been initiated in this country.

Adolescent↗
PubMedDate not supplied

Application of electron microscopy in the definitive diagnosis of effusions.

Electron microscopy was performed on a series of body cavity fluid specimens to evaluate the usefulness of this technique in the diagnosis of effusions. During a six-month period, 42 specimens were examined, 19 benign and 23 malignant. In two cases, the electron microscopic findings were crucial to the diagnosis. In a third case, electron microscopy helped to confirm the diagnosis and avoid unnecessary surgery. In a number of other cases, ultrastructural evaluation demonstrated special cell characteristics not evident in routine light microscopic studies. Based on these findings, we conclude that electron microscopy has a definite place in the diagnosis of effusions and should be increasingly utilized on a selective basis in the evaluation of body cavity fluid specimens. In addition, electron microscopic studies on cells in effusions provide an excellent source of material for educational and research purposes.

Adenocarcinoma↗
PubMedDate not supplied

Distinction between atypical mesothelial cells and malignant cells by scanning electron microscopy.

An examination of body cavity fluid specimens with correlated light, transmission and scanning electron microscopy revealed several surface features that distinguished between malignant cells and atypical mesothelial cells. The microvilli of malignant cells generally were widely distributed and showed a variation in appearance, irregular overlapping and the presence of fused and branched forms. Microvilli on the surface of atypical mesothelial cells were patchy in distribution, relatively uniform in length and diameter and generally lacking in irregular forms. These findings suggest that scanning electron microscopy may be of diagnostic value in the examination of effusions in certain cases.

Breast Neoplasms↗
PubMedDate not supplied

The endomyocardial biopsy.

Endomyocardial biopsy (EMB) provides a safe, simple method of gathering unique information. Although the role of EMB continues to evolve rapidly, present consensus includes the following indications, based on the ability of EMB to provide diagnoses unobtainable by other means: assessment of early rejection following cardiac transplantation; determination of myocarditis as etiology of clinically obscure cardiac dysfunction; quantification of chemotherapeutic (especially anthracycline) cardiotoxicity; and distinction between constrictive and restrictive heart disease. Each of these indications carries major therapeutic as well as prognostic implications. Methods of processing EMB are presented, complications listed, artifacts described, findings and uses illustrated, and suggestions for future development addressed briefly.

Antibiotics, Antineoplastic↗
PubMedDate not supplied

Development of the reproductive organs.

Understanding of the development of the reproductive organs is essential to the evaluation of abnormalities in sexual differentiation. Recent advances resulting from application of genetic, biochemical, and ultrastructural techniques have helped to clarify the mechanisms regulating gonadal and reproductive tract development. The present review considers the major processes of sexual differentiation, development of the female reproductive system and development of the male reproductive system with emphasis on current understanding of basic regulatory mechanisms involved in normal and abnormal development of the reproductive organs.

Cervix Uteri↗
PubMedDate not supplied

Immunohistochemical demonstration of human chorionic gonadotropin in tumors of the urinary bladder.

All transitional cell carcinomas of the bladder diagnosed in male patients within a five year period were studied for human chorionic gonadotropin (hCG) production. Biotin-avidin immunoperoxidase analysis for hCG was performed on all paraffin blocks containing carcinoma-in-situ, grade I, grade II, and grade III transitional cell carcinoma. Of a total of 29 patients, one case of carcinoma-in-situ (1/5), and five cases of grade III transitional cell carcinoma (5/15) were found to have hCG-positive tumor cells. The findings indicate that transitional cell carcinoma should be added to the list of malignant tumors capable of producing hCG.

Adult↗
PubMedDate not supplied

Cytologic diagnosis of multiple myeloma and macroglobulinemia in effusions.

The presence of effusion in association with multiple myeloma or macroglobulinemia is an unusual finding which generally occurs late in the course of the disease. Occasionally, cytoligic detection is a diagnostic problem. In both conditions, the fluid is characrerized by a high specific gravity and high protein content. In myeloma, plasma cells at varying stages of differentiation are present, while in macroglobulinemia atypical lymphocytes and plasma cells resembling those found in the blood and bone marrow are seen. Generally, the diagnosis can be readily made on the basis of clinical features, characteristics of the fluid and cytologic findings. In difficult cases, additional procedures helpful in establishing a definite diagnosis include methyl green pyronine stain, fluid electrophoresis and electron microscopy.

Adult↗