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1.
Clin Transl Oncol ; 22(5): 782-785, 2020 May.
Article in English | MEDLINE | ID: mdl-31359339

ABSTRACT

INTRODUCTION: CD47 over expression has been reported in several tumor subtypes. CD47 interacts with SIRPalpha on macrophages inhibiting phagocytic signal, providing a survival advantage to tumor. CD47, therefore, represents a valuable target for immunotherapy and is currently under clinical investigation. We aimed to study CD47 expression in Hodgkin Reed Sternberg cells (HRS). METHODS: We tested a polyclonal CD47 antibody (LifeSpan Biosciences, Seattle, WA) expression along with classical HRS cell markers on a tissue array of 16 classical Hodgkin Lymphoma (CHL) tumor biopsies obtained from newly diagnosed, non-selected patients (8 Female, 8 Male patients) in our institution from October 2016 to January 2018. Histologic subtypes were nodular sclerosis in 11 cases, mixed Cellularity in 3 cases and lymphocyte rich in 2 additional cases. Median age was 53 years (Range: 8, 74). Early stage disease was found in three patients without unfavorable prognostic factors according to EORTC and GHSG criteria, one patient with unfavorable prognostic factors and nine patients had advanced disease. Bulk disease was present in one patient. Normal lymphoid tissue and normal prostate epithelium were used as normal controls as recommended by manufacturer. Approval from the Local Ethical committee was obtained before any analysis. RESULTS: CD47 was overexpressed on all HRS cells with a characteristic dot-like pattern in 13/13 cases of CHL. HRS clearly expressed CD47 more intensely than infiltrating T and stromal cells. DISCUSSION: We propose that HRS cells, by up-regulating CD47, might avoid innate immunity check on tumor growth, which could be circumvented using blocking monoclonal antibodies.


Subject(s)
CD47 Antigen/metabolism , Hodgkin Disease/pathology , Reed-Sternberg Cells/metabolism , Adolescent , Adult , Aged , Biomarkers, Tumor/metabolism , Child , Female , Hodgkin Disease/metabolism , Humans , Male , Middle Aged , Tissue Array Analysis , Young Adult
3.
Leukemia ; 32(3): 645-653, 2018 03.
Article in English | MEDLINE | ID: mdl-28924241

ABSTRACT

Genome studies of chronic lymphocytic leukemia (CLL) have revealed the remarkable subclonal heterogeneity of the tumors, but the clinical implications of this phenomenon are not well known. We assessed the mutational status of 28 CLL driver genes by deep-targeted next-generation sequencing and copy number alterations (CNA) in 406 previously untreated patients and 48 sequential samples. We detected small subclonal mutations (0.6-25% of cells) in nearly all genes (26/28), and they were the sole alteration in 22% of the mutated cases. CNA tended to be acquired early in the evolution of the disease and remained stable, whereas the mutational heterogeneity increased in a subset of tumors. The prognostic impact of different genes was related to the size of the mutated clone. Combining mutations and CNA, we observed that the accumulation of driver alterations (mutational complexity) gradually shortened the time to first treatment independently of the clonal architecture, IGHV status and Binet stage. Conversely, the overall survival was associated with the increasing subclonal diversity of the tumors but it was related to the age of patients, IGHV and TP53 status of the tumors. In conclusion, our study reveals that both the mutational complexity and subclonal diversity influence the evolution of CLL.


Subject(s)
Biomarkers, Tumor , Clonal Evolution/genetics , Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Mutation/genetics , Adult , Aged , Aged, 80 and over , DNA Copy Number Variations , Disease Progression , Female , Follow-Up Studies , Humans , Leukemia, Lymphocytic, Chronic, B-Cell/diagnosis , Leukemia, Lymphocytic, Chronic, B-Cell/mortality , Male , Middle Aged , Neoplasm Staging , Prognosis , Proportional Hazards Models , Signal Transduction , Young Adult
4.
J Geriatr Oncol ; 6(5): 353-61, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26139300

ABSTRACT

OBJECTIVES: The purpose of this study was to develop a new brief, comprehensive geriatric assessment scale for older patients diagnosed with different hematological malignancies, the Geriatric Assessment in Hematology (GAH scale), and to determine its psychometric properties. MATERIALS AND METHODS: The 30-item GAH scale was designed through a multi-step process to cover 8 relevant dimensions. This is an observational study conducted in 363 patients aged≥65years, newly diagnosed with different hematological malignancies (myelodysplasic syndrome/acute myeloblastic leukemia, multiple myeloma, or chronic lymphocytic leukemia), and treatment-naïve. The scale psychometric validation process included the analyses of feasibility, floor and ceiling effect, validity and reliability criteria. RESULTS: Mean time taken to complete the GAH scale was 11.9±4.7min that improved through a learning-curve effect. Almost 90% of patients completed all items, and no floor or ceiling effects were identified. Criterion validity was supported by reasonable correlations between the GAH scale dimensions and three contrast variables (global health visual analogue scale, ECOG and Karnofsky), except for comorbidities. Factor analysis (supported by the scree plot) revealed nine factors that explained almost 60% of the total variance. Moderate internal consistency reliability was found (Cronbach's α: 0.610), and test-retest was excellent (ICC coefficients, 0.695-0.928). CONCLUSION: Our study suggests that the GAH scale is a valid, internally reliable and a consistent tool to assess health status in older patients with different hematological malignancies. Future large studies should confirm whether the GAH scale may be a tool to improve clinical decision-making in older patients with hematological malignancies.


Subject(s)
Geriatric Assessment/methods , Health Status , Hematologic Neoplasms/psychology , Psychometrics/methods , Aged , Aged, 80 and over , Cross-Sectional Studies , Female , Follow-Up Studies , Hematologic Neoplasms/diagnosis , Hematologic Neoplasms/epidemiology , Humans , Male , Prospective Studies , Reproducibility of Results , Spain/epidemiology , Surveys and Questionnaires
5.
Clin Transl Oncol ; 17(8): 612-9, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25895906

ABSTRACT

PURPOSE: The cure rate in Hodgkin lymphoma is high, but the response along with treatment is still unpredictable and highly variable among patients. Detecting those patients who do not respond to treatment at early stages could bring improvements in their treatment. This research tries to identify the main biological prognostic variables currently gathered at diagnosis and design a simple machine learning methodology to help physicians improve the treatment response assessment. METHODS: We carried out a retrospective analysis of the response to treatment of a cohort of 263 Caucasians who were diagnosed with Hodgkin lymphoma in Asturias (Spain). For that purpose, we used a list of 35 clinical and biological variables that are currently measured at diagnosis before any treatment begins. To establish the list of most discriminatory prognostic variables for treatment response, we designed a machine learning approach based on two different feature selection methods (Fisher's ratio and maximum percentile distance) and backwards recursive feature elimination using a nearest-neighbor classifier (k-NN). The weights of the k-NN classifier were optimized using different terms of the confusion matrix (true- and false-positive rates) to minimize risk in the decisions. RESULTS AND CONCLUSIONS: We found that the optimum strategy to predict treatment response in Hodgkin lymphoma consists in solving two different binary classification problems, discriminating first if the patient is in progressive disease; if not, then discerning among complete and partial remission. Serum ferritin turned to be the most discriminatory variable in predicting treatment response, followed by alanine aminotransferase and alkaline phosphatase. The importance of these prognostic variables suggests a close relationship between inflammation, iron overload, liver damage and the extension of the disease.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Hodgkin Disease/drug therapy , Inflammation/epidemiology , Iron Overload/epidemiology , Liver Diseases/epidemiology , Adult , Aged , Aged, 80 and over , Bleomycin/therapeutic use , Dacarbazine/therapeutic use , Doxorubicin/therapeutic use , Female , Follow-Up Studies , Hodgkin Disease/pathology , Humans , Incidence , Machine Learning , Male , Middle Aged , Neoplasm Staging , Prognosis , Remission Induction , Retrospective Studies , Vinblastine/therapeutic use
6.
Leukemia ; 27(5): 1100-6, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23295735

ABSTRACT

NOTCH1 has been found recurrently mutated in a subset of patients with chronic lymphocytic leukemia (CLL). To analyze biological features and clinical impact of NOTCH1 mutations in CLL, we sequenced this gene in 565 patients. NOTCH1 mutations, found in 63 patients (11%), were associated with unmutated IGHV, high expression of CD38 and ZAP-70, trisomy 12, advanced stage and elevated lactate dehydrogenase. Sequential analysis in 200 patients demonstrated acquisition of mutation in one case (0.5%) and disappearance after treatment in two. Binet A and B patients with NOTCH1-mutated had a shorter time to treatment. NOTCH1-mutated patients were more frequently refractory to therapy and showed shorter progression-free and overall survival after complete remission. Overall survival was shorter in NOTCH1-mutated patients, although not independently from IGHV. NOTCH1 mutation increased the risk of transformation to diffuse large B-cell lymphoma independently from IGHV, with this being validated in resampling tests of replicability. In summary, NOTCH1 mutational status, that was rarely acquired during the course of the disease, identify a genetic subgroup with high risk of transformation and poor outcome. This recently identified genetic subgroup of CLL patients deserves prospective studies to define their best management.


Subject(s)
Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Mutation , Receptor, Notch1/genetics , Cell Transformation, Neoplastic , Female , Humans , Leukemia, Lymphocytic, Chronic, B-Cell/mortality , Leukemia, Lymphocytic, Chronic, B-Cell/pathology , Male , Middle Aged , Risk
7.
Leukemia ; 25(1): 130-4, 2011 Jan.
Article in English | MEDLINE | ID: mdl-21030981

ABSTRACT

Loss of function mutations and deletions encompassing the plant homeodomain finger 6 (PHF6) gene are present in about 20% of T-cell acute lymphoblastic leukemias (ALLs). Here, we report the identification of recurrent mutations in PHF6 in 10/353 adult acute myeloid leukemias (AMLs). Genetic lesions in PHF6 found in AMLs are frameshift and nonsense mutations distributed through the gene or point mutations involving the second plant homeodomain (PHD)-like domain of the protein. As in the case of T-ALL, where PHF6 alterations are found almost exclusively in males, mutations in PHF6 were seven times more prevalent in males than in females with AML. Overall, these results identify PHF6 as a tumor suppressor gene mutated in AML and extend the role of this X-linked tumor suppressor gene in the pathogenesis of hematologic tumors.


Subject(s)
Carrier Proteins/genetics , Leukemia, Myeloid, Acute/genetics , Mutation , Adult , Aged , Animals , Female , Genes, Tumor Suppressor , Hematopoietic Stem Cells/metabolism , Humans , Leukemia, Myeloid, Acute/etiology , Male , Mice , Middle Aged , Myeloid Cells/metabolism , Repressor Proteins , Sex Characteristics
8.
J Clin Pharmacol ; 41(12): 1259-70, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11762553

ABSTRACT

Development of problem-solving skills is vital to professional education as is factual recall. Student mastery must be measured to document student achievement requiredfor completion of educational requirements and professional certification. These measurements also help determine if the educational process is meeting its goal of helping students develop critical cognitive skills for therapeutic problem solving. Testing student growth in the ability to solve problems is less understood. Stressing integration of information across disciplines to derive answers is also important. Test items should resemble the real-world task that students are expected to master. Thatisreallythe essence of content validity, which means faculty should be biased toward presenting information that way. This article is based on a symposium presented at the annual meeting of the American College of Clinical Pharmacology in September 1996. Symposium goals were to define purposes and uses of student evaluations by type and format, including application of techniques that improve evaluation, precision, and validity. Technical applications of computer-based learning and evaluation of problem-solving skills are described. Actual experience with evaluation of problem solving in the curriculum is discussed. The process by which a medical school developed and implemented an evaluation system for a new problem-based curriculum is presented, followed by a critique of the successes and problems encountered during the first year of implementation. Criteria that a well-constructed evaluation program must meet are explored. The approach and philosophy of national standardized testing centers are explained.


Subject(s)
Educational Status , Pharmacology, Clinical/education , Problem-Based Learning , Reproducibility of Results , Software , Teaching
10.
Sangre (Barc) ; 43(3): 236-9, 1998 Jun.
Article in Spanish | MEDLINE | ID: mdl-9741233

ABSTRACT

We report a case of alveolar rhabdomyosarcoma (AR) with massive infiltration of bone marrow at presentation, and initial diagnosis in bone marrow aspirate. A 35 year old man presented with a submandibular mass, and hematomas after mild traumatisms. Peripheral blood showed thrombocytopenia and a normocytic anaemia. Bone marrow film showed diffuse involvement by undifferentiated blasts with rhabdomyoblastic features. Subsequent biopsy of submandibular lymph node confirmed the diagnosis with positivity for specific muscle actin and desmin, and negativity for lymphoid markers. Initial presentation of AR with extensive bone marrow involvement is extremely rare, and it could lead to wrong diagnosis and treatment of acute leukaemia, with the serious consequences that this would have. Immunohistochemical study and morphologic differential features can be of great diagnostic help.


Subject(s)
Anemia/etiology , Bone Marrow/pathology , Hemorrhagic Disorders/etiology , Neoplasms, Unknown Primary/diagnosis , Rhabdomyosarcoma, Alveolar/diagnosis , Rhabdomyosarcoma, Alveolar/etiology , Thrombocytopenia/etiology , Adult , Disease Progression , Fatal Outcome , Humans , Lymph Nodes/pathology , Male , Neoplasms, Unknown Primary/blood , Neoplasms, Unknown Primary/pathology , Pharynx/pathology , Rhabdomyosarcoma, Alveolar/blood supply , Rhabdomyosarcoma, Alveolar/complications , Rhabdomyosarcoma, Alveolar/pathology , Rhabdomyosarcoma, Alveolar/therapy
11.
Cancer Genet Cytogenet ; 100(1): 84-7, 1998 Jan 01.
Article in English | MEDLINE | ID: mdl-9406587

ABSTRACT

We report a case of acute myeloid leukemia (AML) with trisomy 10 as the sole abnormality. We have observed this case among 202 de novo and untreated AML examined cytogenetically in our laboratory during the last 10 years. The patient was an adult man diagnosed with AML-M2. An interesting morphologic finding was the presence in light microscopy and ultrastructural studies of prominent giant "Chediak-Higashi-like" granules in some of the leukemic cells. Cell marker studies showed positivity for CD7 and CD33, as seen in the six previously reported cases. The prognosis has been moderate-good, with a survival of 33 months. Trisomy 10 in AML appears to be a rare recurring numeric chromosomal abnormality and probably linked to a myeloblast subset with a CD33+ and CD7+ phenotype.


Subject(s)
Chromosomes, Human, Pair 10 , Leukemia, Myeloid, Acute/genetics , Trisomy , Aged , Humans , Leukemia, Myeloid, Acute/immunology , Male
13.
Sangre (Barc) ; 39(6): 417-21, 1994 Dec.
Article in Spanish | MEDLINE | ID: mdl-7855692

ABSTRACT

PURPOSE: Antibody formation against red blood cells' antigen is a very important complication due to transfusions, and it can make the following transfusions difficult. To avoid this, it has been proposed giving identical red blood cells for the antigens more frequently involved in sensitizations. To evaluate this fact, we have accomplished a study with the transfused patients in our Hospital since 1990. MATERIAL AND METHODS: 10,308 transfused patients in the Hospital Nitra. Sra. de Covadonga (Oviedo), between January 1990 and March 1994, were studied. The patients have been included in two groups: The first one was constituted by 4,226 patients from the Haematology and the Nephrology Departments, who received red blood cells units compatible with ABO and CcDEe antigens. The second group was formed by the remainding patients transfused with red blood cells compatible only with ABO and D antigens. RESULTS: All 165 antibodies were detected in 132 patients, which means an incidence of 1.3 percent. In 63 cases, antibodies were present before the first transfusion. In the remaining patients, an allosentitization of 0.2 percent in group 1 and 1 percent in group 2 (p < 0.0001) was shown. This difference cannot be explained only for transfusing red blood cells with the same Rh phenotype in the group 1, because a lower immune response had persisted when we analyzed the other antibodies. More than 70 percent of antibodies appeared before the 10th transfusion. DISCUSSION: A lower sensitization exist in the patients of group 1. This seems to be caused by a state of immunosuppression for their disease or their treatments. However, in some patients, the risk of allosensitization persists, so we think it is a good practice to transfuse red blood cells without the most immunogenic antigens in haematological and nephrological patients who already have one antibody.


Subject(s)
Blood Group Antigens , Erythrocyte Transfusion , Erythrocytes/immunology , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Female , Humans , Infant , Male , Middle Aged
14.
Sangre (Barc) ; 38(6): 489-91, 1993 Dec.
Article in Spanish | MEDLINE | ID: mdl-8171385

ABSTRACT

We report a case of a graft-versus-host disease (GVHD) in a patient with non Hodgkin Lymphoma who received multiple blood transfusion for anemia and thrombocytopenia. Although WBC-reduction filters were used, the patient developed a transfusion associated graft-versus-host disease. We do not recommend WBC-reduction filters to prevent postransfusional-GVHD.


Subject(s)
Blood Component Transfusion/adverse effects , Graft vs Host Disease/etiology , Adult , Chronic Disease , Combined Modality Therapy , Fatal Outcome , Filtration , Humans , Immunocompromised Host , Leukocytes , Male
15.
Acad Med ; 68(3): 183-9, 1993 Mar.
Article in English | MEDLINE | ID: mdl-8447906

ABSTRACT

Numerous study commissions have contended that departmental territoriality and lack of coordinated planning are stagnating contemporary medical education. As a cure, these commissions have recommended the creation of centralized academic management units empowered to oversee revitalization of the curriculum through a series of reforms, including better definition of graduation competencies, community-based training, interdisciplinary courses, problem-based learning, and modernization of evaluation strategies. To determine the extent to which these recommendations were being adopted, in 1990 the authors sent a questionnaire on curriculum committee functions, current innovation efforts, and future priorities to academic administrators and members of medical school curriculum committees at 143 North American medical schools. Responses were received from administrators (primarily associate deans for academic affairs) at 118 schools and committee members (primarily faculty) at 111 schools. Recommendations for enhancing curriculum committee effectiveness were also elicited. The authors conclude that centralization of curricular management has occurred at very few institutions, and that the commonly mentioned reforms are being adopted at a modest pace. The results are analyzed in light of theories of the institutional change process and strategies for introducing educational innovations into established institutions.


Subject(s)
Curriculum , Professional Staff Committees/standards , Schools, Medical/standards , Administrative Personnel , Canada , Diffusion of Innovation , Efficiency , Humans , Leadership , Organizational Innovation , Organizational Objectives , Philosophy, Medical , Professional Staff Committees/organization & administration , Professional Staff Committees/trends , Puerto Rico , Schools, Medical/organization & administration , Schools, Medical/trends , Surveys and Questionnaires , United States
16.
J Pediatr Surg ; 20(6): 592-7, 1985 Dec.
Article in English | MEDLINE | ID: mdl-4087083

ABSTRACT

Recent studies of experimental testicular torsion in rats, rabbits, and guinea pigs have demonstrated conflicting evidence regarding contralateral testicular damage. Those studies in which cellular damage has been found are postulated to result from an immunological mechanism whereby the blood-testis barrier is disrupted with subsequent autoantibody formation. In this study, the histologic and immunologic effects of testicular torsion on the contralateral testicle were investigated in prepubertal Chinese hamsters. Four study groups were established; (1) Left orchiectomy only, (2) sham surgery (scrotal incision), (3) 720 degrees left testicular torsion with left orchiectomy 24 hours later, (4) 720 degrees torsion of left testicle with detorsion after 24 hours. The initial procedure was performed at 1 month of age with subsequent biopsies of the contralateral testicle at 1 week, 1 month, and 6 months after the initial procedure. Testicular tissue was examined for immunofluorescent activity using fluorescent labeled goat anti-hamster IgG. Positive controls were established by rabbit immunization (rabbit anti-hamster immunoglobulin) which was subsequently combined with fluorescent labeled goat antirabbit IgG. There was no appreciable difference in immunologic activity between control and experimental animals. Representative sections were examined histologically and no tubular damage was demonstrated and active spermatogenesis was noted at 6 months in all groups. We believe that our results support the premise that testicular torsion in the prepubertal period has no effect on the contralateral testicle.


Subject(s)
Spermatic Cord Torsion/pathology , Testis/pathology , Age Factors , Animals , Antilymphocyte Serum/immunology , Autoantibodies/analysis , Biopsy , Cricetinae , Cricetulus , Female , Immunoglobulin G/analysis , Male , Rabbits , Spermatic Cord Torsion/immunology , Spermatozoa/immunology , Testis/immunology
17.
J Ultrastruct Res ; 84(3): 317-25, 1983 Sep.
Article in English | MEDLINE | ID: mdl-6317882

ABSTRACT

Membrane-bound intranuclear inclusions have been described, for the first time, in the Leydig cell of the Chinese hamster (Cricetulus griseus). The inclusions were not found in the 1-day-old animal, rarely found prior to sexual maturity, and commonly found in the sexually mature animals. The incidence of inclusions increases with aging. Their size and content varies greatly. They are surrounded by a single membrane and completely enclosed by nucleoplasm. Their close association with nuclear invaginations of cytoplasmic material, and their content of cytoplasmic structures along with some exhibiting the presence of trimetaphosphatase reaction product, suggest a cytoplasmic origin. This phenomenon involves the migration of cytoplasmic structures into the nucleus followed by detachment on the nucleoplasmic side. The presence of the inclusions is not an indication of an abnormality of the Leydig cell. The Leydig cell of the Chinese hamster may be an excellent model to study factors that initiate inclusion formation, and to determine the functional role of membrane-bound intranuclear inclusions.


Subject(s)
Acid Anhydride Hydrolases , Cell Nucleus/ultrastructure , Leydig Cells/ultrastructure , Animals , Cricetinae , Cricetulus , Cytoplasm/ultrastructure , Histocytochemistry , Male , Microscopy, Electron , Nuclear Envelope/ultrastructure , Phosphoric Monoester Hydrolases , Sexual Maturation
18.
J Endocrinol Invest ; 6(3): 161-7, 1983 Jun.
Article in English | MEDLINE | ID: mdl-6619526

ABSTRACT

Trypan blue was previously shown to directly inhibit thyroid secretion following TSH stimulation. Inhibition of both colloid droplet formation and thyroglobulin proteolysis was demonstrated. By observing the characteristic bright red fluorescence of the dye-protein complex, we have demonstrated that trypan blue rapidly enters the colloid space and combines with thyroglobulin. In addition, the dye in association with thyroglobulin has been demonstrated within phagosomes and phagolysosomes by centrifugation of the lysosomal (P15) fraction on both sucrose and Percoll density gradients. Lability or latency of the dye with the phagolysosomal contents was demonstrated and the dye was found in association with thyroglobulin by column chromatography. It is proposed that the complexing of trypan blue to thyroglobulin alters its attachment to specific follicular cell receptors, inhibits pinocytosis, and, thus, thyroid hormone secretion.


Subject(s)
Thyroglobulin/metabolism , Thyroid Gland/metabolism , Thyrotropin/metabolism , Trypan Blue/pharmacology , Animals , Cattle , Centrifugation, Density Gradient , Chromatography, Gel , In Vitro Techniques , Lysosomes/metabolism , Mice , Microscopy, Fluorescence , Phagocytosis , Thyroid Gland/analysis , Thyroid Gland/ultrastructure
19.
J Ultrastruct Res ; 83(2): 161-7, 1983 May.
Article in English | MEDLINE | ID: mdl-6306263

ABSTRACT

The ultrastructure of two types of paracrystalline inclusions is described, for the first time, in the Leydig cell of the Chinese hamster (Cricetulus griseus). The subunit of both types of inclusions consists of 5-nm-wide microfilaments differing only in the arrangement and shape of the microfilaments. The electron-dense microfilaments of the type A inclusion are usually in a serrated pattern with an equidistant 5-nm interval separating them. The type B inclusion has pairs of straight microfilaments separated by a 5-nm interval. Other microfilaments course at right angles to the paired units. Both types of inclusions are absent in the newborn, rarely found in the sexually immature, and commonly found in the sexually mature and aged animals. Both inclusions are found in the cytoplasm of Leydig cells, but only the A inclusion is found in the nucleoplasm. Their functional role is not yet determined, but the inclusions are commonly found in Leydig cells whose ultrastructural characteristics indicate normal steroidogenesis.


Subject(s)
Inclusion Bodies/ultrastructure , Leydig Cells/ultrastructure , Aging , Animals , Cricetinae , Cricetulus , Crystallography , Male , Microscopy, Electron
20.
Cell Tissue Res ; 224(1): 195-206, 1982.
Article in English | MEDLINE | ID: mdl-7094008

ABSTRACT

An ultrastructural and morphometric analysis was made of the nucleolar components in pinealocytes of 40 male Fischer rats sampled at eight times in an LD 12:12 photoperiod cycle. Comparisons of results from the eight times showed variation in estimated mean volume of the granular component of +/- 29%, and of the fibrillar component +/- 11%, in relation to daily means. Peaks in mean volume of total nucleolus and its granular component occurred at 1 h of light. Near maximal and minimal mean volumes of the fibrillar component both occurred during both light and dark. Fibrillar centers (nucleolar organizer regions) of different sizes were found at all sampling times. It is concluded that temporal patterns in 24-h changes in the nucleolar components are most prominent in the granular component, and are more complex than suggested by changes in total nucleolar size or mean dimensions, and than represented by a simple biphasic circadian rhythm. Examples of different stages in the migration of the granular component, and of possible sites of nucleo-cytoplasmic transfer of nucleolar material, are described.


Subject(s)
Light , Pineal Gland/ultrastructure , Animals , Cell Nucleolus/ultrastructure , Cytoplasm/ultrastructure , Male , Microscopy, Electron , Nuclear Envelope/ultrastructure , Periodicity , Rats
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