Showing papers by "University of Texas System published in 1981"

Localization of single copy DNA sequences of G-banded human chromosomes by in situ hybridization.

Abstract: Recombinant lambda bacteriophage clone H3 containing a human DNA segment of 14.9 kb present in one or two copies per haploid genome was isolated. In situ hybridization in human metaphase chromosomes of the 3H-labeled cloned DNA resulted in highly significant labeling (53% of cells) of band p36 of chromosome 1, such that 22% of all chromosomal grains were located on this region. Hybridization was dependent upon the presence of dextran sulfate in the hybridization mixture and was not affected by repetitive DNA competitor. These results demonstrate localization of a single copy sequence on human metaphase chromosomes.

Conservative surgery and postoperative radiotherapy in 300 adults with soft-tissue sarcomas

Abstract: From January 1963 through December 1977, 300 adults with soft-tissue sarcomas were treated by a conservative surgical excision and postoperative radiotherapy. The absolute two- and five-year disease-free survival rates are 74% (222/300) and 61.3% (103/168), respectively. The five-year survival rate varies with: (1) anatomic site, e.g., 69.4% (75/108) for extremity lesions vs. 33% (5/15) for abdominal lesions; (2) histopathologic diagnosis, e.g., 86.4% (19/22) for fibrosarcoma vs. 50% (15/30) for neurofibrosarcoma; and (3) stage of the lesion. The overall local recurrence rate was 22.3% (67/300) and 27% (81/300) of the patients developed distant metastases. The incidence of lymph node metastases as an initial site of spread was only 2.7% (8/300); therefore, elective treatment of the regional lymphatics is not indicated. The 6.5% incidence of significant complications in extremities is low and might be further diminished by careful treatment planning. The combination of conservative surgery and postoperative radiation therapy maintains a functional limb in 84.5% (169/200) of patients with extremity lesions. This rate is comparable to the five-year survival rate attained with radical surgery.

Angiosarcoma of skin and soft tissue: A study of forty-four cases

Abstract: Forty-four cases of skin and soft tissue angiosarcoma seen at M. D. Anderson Hospital before 1976 were reviewed. The cases fell into six different clinical groups: scalp-face, 17 cases; postmastectomy, 14 cases; postradiation, 5 cases; leg with vascular stasis, 2 cases; breast, 2 cases; and miscellaneous, 4 cases. In all cases in the first four groups, the tumors involved primarily the dermis and subcutis and showed similar blends of vasoformative and solid histologic patterns. Two tumors in the miscellaneous group closely resembled those in the larger groups, but the other two in that group (both located in deeper soft tissue sites) and the two breast angiosarcomas had a somewhat different microscopic appearance. Survival was generally poor in all groups, owing to frequent local recurrence and early metastasis; median survival for the entire series was 20 months. Findings of significantly favorable prognostic importance were tumor size less than 5 cm (in the scalp-face group) and a moderate or marked lymphoid infiltrate in and around the tumor. Less significant favorable factors were a distal location ( in the postmastectomy group) and a low degree of pleomorphism. Only nine patients had long-term, disease-free survival.

Electron beam dose calculations.

Abstract: Electron beam dose distributions in the presence of inhomogeneous tissue are calculated by an algorithm that sums the dose distribution of individual pencil beams. The off-axis dependence of the pencil beam dose distribution is described by the Fermi-Eyges theory of thick-target multiple Coulomb scattering. Measured square-field depth-dose data serve as input for the calculations. Air gap corrections are incorporated and use data from 'in-air' measurements in the penumbra of the beam. The effective depth, used to evaluate depth-dose, and the sigma of the off-axis Gaussian spread against depth are calculated by recursion relations from a CT data matrix for the material underlying individual pencil beams. The correlation of CT number with relative linear stopping power and relative linear scattering power for various tissues is shown. The results of calculations are verified by comparison with measurements in a 17 MeV electron beam from the Therac 20 linear accelerator. Calculated isodose lines agree nominally to within 2 mm of measurements in a water phantom. Similar agreement is observed in cork slabs simulating lung. Calculations beneath a bone substitute illustrate a weakness in the calculation. Finally a case of carcinoma in the maxillary antrum is studied. The theory suggests an alternative method for the calculation of depth-dose of rectangular fields.

Mammalian in vivo and in vitro cytogenetic assays: a report of the U.S. EPA's gene-tox program.

Abstract: This report presents an assessment made by the U.S. Environmental Protection Agency Gene-Tox Program's Work Group on mammalian cytogenetics of the clastogenic effects of chemicals in in vivo and in vitro mammalian cell assays. This assessment is based on information provided by the Environmental Mutagen Information Center, Oak Ridge National Laboratory, with the proviso that the experimental protocol used in these papers was adjudged to be acceptable by standards outlined by the Work Group. Some data were accepted as "qualitative only" because the protocol used was fairly close to that proposed as suitable. Using these criteria, 177 papers were selected for review. 6 assays were reviewed: bone marrow (32 papers, 31 chemicals), spermatogonial (10 papers, 10 chemicals), spermatocyte (25 papers, 25 chemicals), oocyte or early embryo (18 papers, 19 chemicals), in vitro cell culture (30 papers, 66 chemicals), and leukocyte (66 papers, 53 chemicals). Each assay was considered separately, and comparisons were then made between them for their similarities or differences in producing a positive or negative clastogenic effect of a particular chemical or chemical class. A large proportion of the available cytogenetic data was not suitable for inclusion in the final data base because of poor experimental design or unsatisfactory reporting of the information. It was not possible to recommend any one assay for determining potential clastogenicity because each had its own particular advantages and limitations and provided unique information. For demonstrating in vivo effects, the bone-marrow assay is probably the simplest and most economical. If only in vitro exposures were considered, leukocytes or cultured mammalian cell lines would be suitable. However, there are advantages to using leukocytes because they are a synchronous population, at least through their cell division, and because of the ready availability of human cells. In general, there was good agreement between clastogenicity and carcinogenicity.

Megavoltage irradiation of epithelial tumors of the nasopharynx

Abstract: The present analysis is limited to 251 patients treated with megavoltage irradiation at M. D. Anderson Hospital and Tumor Institute between 1954 and December 1977. The 5-year actuarial disease-free survival for all patients studied is 52%; it is 42%, 65%, and 14%, respectively, for those with squamous cell carcinoma, lympbepitbelioma, and unclassified carcinoma. There were 49 (19.5%) local failures, 32 (12.7%) regional failures, and 73 (29.19%) distant metastases. A previous review had shown an unsatiafactory control rate for T 1 and T 2 squamous cell carcinoma, the reason for which may have been that the actual delivered dose to the nasopbarynx was less thin the calculated dose. Since 1972, an additional 500 to 750 rad has been delivered through parallel opposed small fields centered over the angle of the nassopharynx. Thus, this analysis is divided into two periods, 1954 through December 1971, and January 1972 through December 1977, to evaluate the effectiveness of the treatment changes. The control rate for T 1 and T 2 squamous cell carcinomas has increased from 76.4% to 94.2%.

Purification of Rat Spermatogenic Cells and Preliminary Biochemical Analysis of These Cells

Abstract: A method forobtaininghighlypurifiedfractions of rat testicular cells is described. Single cell suspensions from adult rat testes were separated by centrifugal elutriation. Fractions enriched in pachytene primary spermatocytes, early spermatids, and cytoplasts detached from late spermatids were obtained. These fractions were further separated by equilibrium density centrifugation on gradients of Percoll. In this manner fractions of 3 X 10� pachytene spermatocytes (98% purity), 1.1 X 10� early spermatids (93% purity), and 1.1 X i05 cytoplasts (98% purity) were obtained within 6 h after sacrificing the rats. The cells appeared to be morphologically intact and to have retained their biochemical integrity. Analysis of acid-soluble nuclear proteins by polyacrylamide gel electrophoresis showed that histone 4 is synthesized during the pachytene stage, and confirmed that testis-specific histones are also synthesized during this stage. Analysis of a microsomal RNA preparation from purified pachytene spermatocytes and purified early spermatids by sucrose gradients indicated that intact ribosomal RNA (rRNA) can be obtained from purified cells. Both cell types are active in synthesizing presumptive messenger RNA (mRNA) with a wide range of sedimentation values, but no appreciable rRNA synthesis was detected.

Leiomyosarcoma of soft tissue: A clinicopathologic study

Abstract: The case records and histologic material of 28 patients with leiomyosarcoma of soft tissue treated at M. D. Anderson Hospital between 1948 and 1975 were reviewed. These included patients in whom the tumors arose in the retroperitoneum (16), major blood vessels (3), and other soft-tissue sites, collectively designated peripheral soft tissue (9). Follow-up was complete in all cases. A striking preponderance of female patients was observed in the group with retroperitoneal tumors, in contrast to the male preponderance in the vascular and peripheral soft tissue tumor groups. Tumor size and location were the major prognostic factors; large size (greater than 5 cm) and retroperitoneal origin were associated with a much poorer clinical outcome than smaller size (less than 5 cm) and origin elsewhere than the retroperitoneum. These factors were related, since all retroperitoneal tumors were large. Microscopic appearance did not correlate significantly with clinical course. The clinical approach to these tumors is discussed in light of the findings of this study.

Sarcomatoid squamous cell carcinoma of the mucous membranes of the head and neck: a clinicopathologic study of 20 cases.

Abstract: Twenty cases of head and neck mucosal squamous cell carcinoma containing a prominent sarcomatoid element were reviewed with special attention to possible prognostic factors. Patients whose tumors invaded muscle, minor salivary or accessory respiratory glands, or bone had very poor survival rates, whereas those whose tumors were superficial and did not extend into any of these structures had excellent survival rates. A history of irradiation to the tumor site and tumor location in the oral cavity rather than the larynx, pharynx, nasal cavity, or nasal-associated structures were associated with invasiveness and thus with poorer survival. Aside from invasion, histologic features and gross configuration were not found to be of significant prognostic importance.

Age-Related Changes in the Leydig Cell Population, Seminiferous Tubules, and Sperm Production in Stallions

Abstract: Age-related changes in the Leydig cell population of horses between 2 and 20 years old were characterized by a twofold increase in Leydig cell number per gram parenchyma, a threefold increase in Leydig cell number per testis, a threefold increase in Leydig cell volume per gram parenchyma, and a fivefold increase in Leydig cell volume per testis. Due to the increased volume of Leydig cells per gram of testicular parenchyma and the increased size and accumulation of lipofuscin granules in individual cells, the gross appearance of the parenchyma became darker with age. The Leydig cell population increased with age by replacing the noncellular components of the interstitium and did not alter the proportion of the testis occupied by blood vessels, lymph vessels, or seminiferous tubules. Both the diameter and length of seminiferous tubules increased with age. Daily sperm production per testis increased between postpuberty and adulthood yet did not increase significantly beyond adulthood. However, the number of Leydig cells per testis continued to increase in the aging horse. Other significant changes included increases in testicular weight, volume of Leydig cells per testis, seminiferous tubular length per testis, and daily sperm production per testis in April-May compared with February-March.

Estrogen receptor: a prognostic factor in breast cancer.

Abstract: Two-hundred-seventeen women with primary breast carcinoma had an estrogen receptor determination tested by both the dextran-coated charcoal assay and sucrose density gradient. The results were correlated with the disease-free interval, survival, response to hormone therapy or chemotherapy, and site of recurrent disease. The disease-free interval (DFI) was significantly longer in premenopausal patients with estrogen receptor positive (ER+) determination compared with premenopausal patients with estrogen receptor negative (ER-) determinations, irrespective of nodal involvement (P less than 0.05). There was no difference between the postmenopausal patients. The survival of the ER+ patients was statistically longer than that of the ER- patients (P less than 0.05). Statistical significance remained when the patients were grouped according to menopausal status or nodal involvement (P less than 0.002 or less). Sixty-two patients were treated with hormonal therapy, either ablative or additive. Forty-eight percent of patients with ER+ responded compared with 6% of patients with ER- (P less than 0.0005). Seventy-nine patients received chemotherapy; 52% of the ER+ and 57% of the ER- patients responded (P less than 0.5). ER+ tumors had a predilection to metastasize in skin and bone, while ER- tumors metastasized more commonly to the viscera and brain.

Phenotypic drift of metastatic and cell‐surface properties of mammary adenocarcinoma cell clones during growth in vitro

Abstract: We have examined cell clones obtained from a 13762 mammary adenocarcinoma tumor and its spontaneous lung metastasis for phenotypic stability during serial culture passage in vitro. Two clones that varied markedly in their metastatic properties were chosen for further examination. One of these clones (MTC) obtained from the parental transplanted tumor initially failed to metastasize within 23 days post-injection s.c. but gained the ability to form spontaneous pulmonary metastases after several serial passages in vitro. Another clone (MTLn3) derived from a spontaneous lung metastasis was initially highly metastatic after short-term culture, but lost the potential to form large numbers of spontaneous lung metastases with long-term culture. In contrast to MTA, clone MTLn3 displayed lymph-node metastasis, and the frequency of lymph-node involvement increased when late-passage cultures of MTLn3 cells were assayed in vivo. Both clones from late-passage cultures produced larger tumor sizes at the primary (mammary fat pad) injection sites compared to early passage cells. The morphologies of MTC cells changed with serial tissue culture passage, while the morphologies of MTLn3 cells did not change. The display of fibronectin on MTC cells by immunofluorescence did not change with culture passage; fibronectin was not detected in cultures of clone MTLn3. Fibronectin was also found on MTC cells by cell surface labelling using lactoperoxidase-catalyzed iodination-sodium dodecylsulfate polyacrylamide gel electrophoresis-autoradio-graphy. lodination of fibronectin on MTC cells did not vary with culture passage, and as in immunofluorescence experiments it was not detected on MTLn3 cells. There was a decrease in exposure of certain cell surface proteins on MTC cells with culture passage, but we did not detect modifications with this procedure that correlated with culture passage of MTLn3 cells. We conclude that prolonged culture in vitro can result in modifications of metastatic and cell-surface properties of tumor cell clones.

Elevated beta thromboglobulin in peripheral venous blood of patients with acute myocardial ischemia: Direct evidence for enhanced platelet reactivity in vivo☆

Abstract: Levels of beta thromboglobulin, a platelet-specific protein, in platelet-poor plasma from peripheral venous samples of patients with acute myocardial ischemia were measured in order to obtain direct evidence for enhanced platelet reactivity in vivo in these patients and to determine the value of beta thromboglobulin assay in studying platelet reactivity in patients with ischemic heart disease The normal beta thromboglobulin concentration in peripheral venous plasma, determined from normal volunteers and patients without known ischemic heart disease or disorders associated with enhanced platelet destruction (control group without platelet destruction), was 300 ± 126 ng/ml (mean ± standarddeviation) (range 10 to 59) The mean beta thromboglobulin level in hospitalized patients with chest pain judged not to be due to acute myocardial ischemia was 337 ± 120 (range 11 to 65) Patients with deep venous thrombosis, disseminated intravascular coagulation, thrombotic thrombocytopenic purpura and idiopathic thrombocytopenic purpura provided a control group of patients with enhanced platelet destruction; the beta thromboglobulin level in this group was 1310 ± 126 ng/ml (range 38 to 250) Elevated beta thromboglobulin levels were observed in 4 (16 percent) of 25 patients with stable angina pectoris (mean 450 ± 226 ng/ml, range 22 to 125), in 23 (59 percent) of 39 patients with unstable angina pectoris (mean 832 ± 737 ng/ml, range 14 to 910) and in 12 (80 percent) of 15 patients with acute myocardial Infarction (mean 1185 ± 662 ng/ml, range 30 to 420) on one or more occasions during hospitalization The mean values of patients with platelet destruction in the control group (p <0001), patients with acute myocardial infarction (p <0005) and patients with unstable angina pectoris (p <0025) were significantly elevated with respect to values in patients without platelet destruction in the control group The beta thromboglobulin levels of patients with acute myocardial infarction generally remained elevated during the first 3 to 4 hospital days Elevation of beta thromboglobulin levels in patients with acute myocardial ischemia provides direct evidence for enhanced platelet reactivity in these patients However, the temporal relation of the elevated beta thromboglobulin values with clinical deterioration was imprecise, so that it can not be determined from this study whether the enhanced platelet reactivity was a cause or an effect of the acute myocardial ischemia in these patients Assay of beta thromboglobulin appears to be suitable as an indicator of enhanced platelet reactivity in patients with ischemic heart disease Its use obviates many of the difficulties in interpretation of the various in vitro analyses of platelet function and platelet survival studies

Natural history of central nervous system acute leukemia in adults.

Abstract: Central nervous system (CNS) involvement occurred in 45 of 222 (20.3%) leukemic adults achieving bone marrow (BM) complete remission (CR), including 12 of 23 (52%) acute undifferentiated leukemia (AUL), 12 of 32 (39%) lymphoma leukemia, 5 of 26 (19%) acute lymphoblastic leukemia, and 16 of 142 (11%) acute myelogenous leukemia. Risk factors for CNS disease were lactic dehydrogenase (LDH) greater than or equal to 25,000/mm3. AUL morphology, age less than 20 years, and extramedullary involvement were most significant. Pattern of CNS involvement varied with morphology. Survival after CNS relapse depended most on BM status and symptoms. Duration of CNS CR was longest for asymptomatic patients with low CSF cell counts. Also important were duration of first BM CR, ease of achievement of initial BM CR, and leukocyte count (original and at most closely antecedent BM involvement), reflecting the common origin of BM and CNS leukemic cells. Central nervous system relapse generally did not shorten BM CR or survival, although early primary CNS relapse was associated with early BM relapse.

A four‐year experience with anthracycline, cytosine arabinoside, vincristine and prednisone combination chemotherapy in 325 adults with acute leukemia

Abstract: Combination chemotherapy with an anthracycline, Adriamycin or rubidazone, cytosine arabinoside, vincristine and prednisone resulted in a complete remission rate of 62% in 325 consecutive unselected adults with acute leukemia. The results by morphologic categories were 58% for acute myelogenous leukemia (AML), 70% for acute undifferentiated leukemia (AUL), and 77% for acute lymphoblastic leukemia (ALL). The median survival was 43 weeks. Ten percent of all patients are projected to be alive and in remission at five years. The median remission duration for the whole group was 51 weeks, durations being significantly longer for AML (60 wks) than ALL (30 wks) and AUL (21 wks). Central nervous system involvement was uncommon in AML (4%), but much more common in patients with AUL (37%) and ALL (32%). One in five complete responders with AML is projected to be in their first remission at five years off all chemotherapy. Age, sex, morphology, cytogenetic pattern, temperature at presentation, and presence of a documented preceding hematologic abnormality are found to be significant variables for response and survival.

An Aminopeptidase from Bovine Brain Which Catalyzes the Hydrolysis of Enkephalin

Abstract: An aminopeptidase from bovine brain which catalyzes the hydrolysis of the tyrosyl1-glycine2 bond of methionine5-enkephalin has been purified to electrophoretic homogeneity. The enzyme also catalyzes the hydrolysis of di-peptides, tripeptides, and amino acid β-naphthylamides. The enzyme can be inactivated by dialysis against EDTA, and reconstituted with divalent metal ions. Inhibition of the enzyme is observed in the presence of p-chloromercuribenzoate and puromycin, the latter compound not being hydro-lyzed by the enzyme. The enzyme is composed of a single polypeptide chain of molecular weight approx. 100,000. The properties of this enzyme are similar to those reported for other brain aminopeptidases active on enkephalin, although distinct differences are observed.

A New Approach to Quantification of Spermatogenesis and Its Application to Germinal Cell Attrition During Human Spermiogenesis

Abstract: A new approach to quantification of spermatogenesis has been applied to human testes to investigate germinal cell attrition during spermiogenesis and to derive an appropriate time divisor for the determination of daily sperm production from numbers of homogenization-resistant spermatids in unfixed human testes. Glutaraldehyde fixation of testes from 10 men rendered nuclei of even the most immature germinal cells resistant to homogenization. Prevention of dissolution of cell nuclei during homogenization permitted enumeration of the entire constellation of germinal cell nuclei by phase-contrast microscopy. Thus, investigation of attrition during spermatogenesis became possible. Since daily sperm production per gram of parenchyma (DSP/g) was similar (P>0.05) when based on enumeration of round spermatids (5.5 X 10’), maturation-phase spermatids (5.8 X 106), and all spermatids (5.9 X 106), no attrition was detected during human spermiogenesis. Agreement (P>0.05) between these three estimates and DSP/g based on histometric analysis of round spermatids in the same testes (5.9 X 106) validated the new technique for quantifying spermatogenesis. The number of homogenization-resistant spermatids in unfixed tissue was only 37% of the number of maturation-phase spermatids in homogenates of fixed, contralateral testes. Thus, previous estimates of DSP/g in humans from homogenates of unfixed testis are low and should be approximated by multiplying published data by the reciprocal of 0.37 (i.e., 2.7). When the corrected time divisor of 2.9 days (7.9-day time divisor for maturation-phase spermatids multiplied by the correction factor of 0.37) was employed to convert numbers of homogenization-resistant spermatids from unfixed testes to DSP, a value of 5.6 X 106 was obtained for these 10 men. No difference (P>0.05) was found among the five estimates of DSP/g.

Role of estrogen in the dopaminergic control of prolactin secretion

Abstract: The effect of estrogen on the dopaminergic control of PRL secretion was investigated. Treatment of ovariectomized rats with estradiol benzoate (25 microgram/kg, sc) daily for 5 days resulted in a marked elevation of the serum PRL concentration. This estrogen-induced increase in serum PRL levels was apparently not the result of a suppressed release of dopamine into hypophysial portal blood, since the mean dopamine concentration in hypophysial portal plasma in estrogen-treated rats was 2.5 times that in vehicle-treated animals. It was found that under in vitro conditions, dopamine was much less effective in inhibiting the release of PRL from pituitary glands of estrogen-treated rats than from glands of vehicle-treated controls. The capacity of PRL cells to internalize dopamine and incorporate it into PRL secretory granules was evaluated in anterior pituitary tissue obtained from estrogen- or vehicle-treated animals. When tissue fragments of the anterior pituitary gland were incubated in the presence of dopamine (10(-5) M) for 30 min at 37 C and then homogenized and fractionated by means of continuous sucrose density gradient centrifugation, it was found that the amount of dopamine associated with PRL granules from anterior lobe tissue of estrogen-treated rats was only 40% of that from the tissue of vehicle-treated controls. These results are supportive of the hypothesis that the ability of estrogen to antagonize the inhibitory action of dopamine on PRL secretion is mediated through an estrogen-induced reduction in the capacity of the PRL cell to incorporate dopamine into PRL secretory granules. (Endocrinology 108: 440, 1981)

The tectopontine projection in the rat with comments on visual pathways to the basilar pons

Abstract: The projection from the superior and inferior colliculi to the basilar pons in the rat was studied with the technique of orthograde transport of labeled amino acids and autoradiography. Injections restricted to the medial or lateral regions of the superior colliculus gave rise to grain labeling representing terminal fields over the ipsilateral peduncular, dorsolateral, and ventrolateral regions of the caudal basilar pons and over the dorsomedial area of the contralateral nucleus reticularis tegmenti pontis (NRTP). The pontine projection from the superior colliculus to the lateral basilar pons is topographically organized; the medial superior colliculus projects primarily to the peduncular region, whereas the lateral superior colliculus terminates chiefly in ventrolateral pontine areas. A projection from the superior colliculus to the contralateral dorsomedial pontine and medial peduncular pontine regions, a previously undescribed finding, has also been shown. Descending fibers from the inferior colliculus do not appear to terminate extensively within the basilar pons but rather course adjacent to pontine cells of the dorsolateral region in the caudal pons. Pretectal nuclei project ipsilaterally to medial and lateral nuclei in the rostral and middle basilar pons, respectively. A rostrocaudal topography exists in the tectopontine projection; the pretectum projects to rostromiddle basilar pons, the superiormore » colliculus to more caudal pontine regions, and the inferior colliculus (although sparsely) to further caudal areas. The pontine projection pattern from the colliculi and pretectum differs from the pontine afferents from the visual cortices.« less

Iontophoretic catheter device

Abstract: A urinary catheter which comprises two internal heavy metal-containing electrodes disposed proximate the distal orifice of the catheter. The catheter is adapted for iontophoresis application for the purpose of preventing bacterial infection associated with catheterization procedures. Provision is made for connecting the electrodes to a constant electromotive force source. Iontophoretic operation of the catheter employs electromotive force to generate heavy metal ions at the electrode surfaces. The heavy metal ions are driven into an electrolyte solution provided by urine or tissue fluid near the site of the catheter tip. Heavy metal ions such as gold, silver, platinum, iron, and copper have been demonstrated to have antibacterial activity.

Clinicopathologic correlates of acute ischemic heart disease syndromes

Abstract: To better define the relations among acute and chronic coronary arterial lesions and different syndromes of acute ischemic heart disease, the clinicopathologic findings in 100 recent myocardial infarcts in 83 patients were reviewed and the results correlated with those of previous studies. Severe atherosclerosis (greater than 75 percent narrowing of luminal cross-sectional area) involved three or more major coronary arteries in 65 percent; two arteries in 16 percent, one artery in 15 percent, and no arteries in 4 percent of cases. The incidence rate of recent occlusive coronary arterial lesions was 61 percent, including 50 (90.2 percent) of 55 grossly apparent transmural infarcts, 9 (34.6 percent) of 26 grossly evident subendocardial infarcts and 2 (10.5 percent) of 19 multifocal microinfarcts associated with clinical episodes of acute coronary insufficiency (p From this and previous studies, it is concluded that (1) acute ischemic heart disease does not have a constant relation with the severity of chronic atherosclerosis; (2) myocardial necrosis commonly occurs in the absence of acute permanent coronary occlusion, but in this setting is usually limited to subendocardial involvement of variable extent; (3) acute coronary thrombosis frequently acts as a major factor in determining the extent and distribution of an evolving infarct, as indicated by the large incidence of occlusive coronary thrombi with regional transmural infarcts; and (4) coronary thrombus formation is not dependent on a generalized impairment of coronary perfusion, either before or after the onset of infarction.

The Androgen Status of Aging Male Rats

Abstract: In male Sprague-Dawley rats between 3–24 months of age, plasma concentrations of testosterone declined by more than 50% while concentrations of LH in plasma remained relatively constant. During the same interval, body weight rose almost 50%, suggesting that total circulating amounts of testosterone, assuming a proportional expansion of plasma volume, remained relatively constant with increasing age and that total LH in the circulation actually increased in older rats. This assumption was justified by demonstrating that blood plasma volume increased in proportion to body weight over the range of ages and weights represented by rats in this study. Plasma testosterone levels achieved after the injection of gonadotropin were significantly lower in the oldest rats, but when adjusted for increased plasma volume, total testosterone added to the circulation in response to injected gonadotropin did not diminish with age. Age-related change was not detected in testosterone secretion by decapsulated rat testes, eith...

Factor VIII in Kaposi's sarcoma.

Abstract: The immunoperoxidase technic was applied to 15 skin lesions of Kaposi's sarcoma to localize factor VIII-related antigen. Factor VIII-related antigen serves as a tissue-specific marker for endothelial cells. Positive staining was observed in all cases. These findings support the endothelial origin of the lesion of Kaposi's sarcoma.

131I therapy in differentiated thyroid carcinoma: M. D. Anderson Hospital experience.

Abstract: The therapeutic response and survival rates of 352 patients with differentiated thyroid carcinoma who had received radioactive iodine therapy since 1951 were studied. Of these patients, 72% had metastases to the cervical lymph nodes, lungs, bone, or other viscera. Of all patients, 70% showed complete remission, and 30% showed partial response or recurrence of disease or both. Patients with metastases before therapy had a higher incidence of recurrence than those who had localized thyroid disease (32.4% vs. 15.1%). Of these, 97 patients had recurrent disease. In 24 of these patients, the recurrent tumor failed to take iodine, indicating change in its iodine-concentrating characteristics. Of the 352 patients, 44 (12.5%) died of progressive thyroid carcinoma, and all were over 40 years of age at the time of initial diagnosis. Mean survival of patients with metastatic disease who were over 40 years of age at initial diagnosis was significantly lower than that of patients under 40 years of age (6.2 years vs. 11.5 years). Patients with recurrent metastases unresponsive to surgery or radioactive iodine therapy were treated with palliative radiotherapy or chemotherapy or both. They respond poorly and died within a few months.