Showing papers by "Tufts University published in 1972"
TL;DR: The observations underlying this hypothesis have been amply confirmed and extended and a GH-dependent plasma factor stimulates in cartilage not only the incorporation of sulphate into chondroitin sulphate, but also the incorporate of thymidine into DNA and proline into the hydroxyproline of collagen.
Abstract: THE action of growth hormone (GH) on skeletal tissue was proposed to be mediated through a secondary substance, described by the operational term “sulphation factor”1 The observations underlying this hypothesis have been amply confirmed and extended A GH-dependent plasma factor stimulates in cartilage not only the incorporation of sulphate into chondroitin sulphate, but also the incorporation of thymidine into DNA2, proline into the hydroxyproline of collagen3 and uridine into RNA4 GH has substantially no in vitro effect on cartilage metabolism
851 citations
TL;DR: The product of Sed and (dV/VdP) ed provides a normalized index of “muscle fiber stretch,” which permits one to compare length-tension or length-work relationships in diseased ventricles of varying dimensions and compliance.
Abstract: Left ventricular circumferential end-diastolic stress (Sed), peak systolic stress (Sps), and compliance at end-diastole ([dV/VdP]ed) were estimated in 13 subjects with normal left ventricles (N group), nine subjects with inappropriate hypertrophy (IH group), five with aortic valvular stenosis (AS group), and six with congestive cardiomyopathy (CC group). The product of Sed and (dV/dP)ed was employed as an index of "muscle fiber stretch" and related to systolic indices of ventricular performance. Compliance was significantly less than normal in IH (P < 0.001), in AS (P < 0.01), and in CC (P < 0.001), while end-diastolic volumes were smaller than normal (P < 0.05), normal (P = ns), and larger than normal (P < 0.001) in the three groups, respectively. Sed was normal in IH and AS but elevated in CC (P < 0.001), while Sps was decreased in IH and normal in AS and CC. "Muscle fiber stretch," however, was substantially less than normal in IH (P < 0.001), indicating that the low Sps is due at least in part to shor...
324 citations
TL;DR: Success and failure in 253 cases selected at random were determined by mounting the films and having six examiners read them, independently and without consulting one another.
315 citations
265 citations
TL;DR: The data suggest that intermittent endotoxemia may be a wave of differentiation from a precursor compartment with subsequent maturation in CF1 mice, and sequential increases in the myeloblast-promyelocyte and myelocyte compartments of the marrow at 24 to 48 hours, respectively.
Abstract: To study the regulation of granulopoiesis, we measured the effect of endotoxin on peripheral leukocyte counts and on colony-stimulating factor (CSF) in the serum of CF1 mice. The peripheral granulocyte level fell from 612 ± 69 (mean ± S.E.M.) to 147 ± 20 per cubic millimeter within 45 minutes of intraperitoneal injection of 5 μg of Salmonella typhosa endotoxin. In control animals, the CSF in 0.1 ml of serum stimulated the growth of 0.56 ± 0.4 in vitro myeloid colonies per 105 cells. Forty-five minutes after endotoxin the CSF activity had increased to 7.7 ± 6.1 colonies per 105 cells; after two hours it was 29.6 ± 10 colonies per 105 cells. Six hours after endotoxin the marrow was depleted of polymorphonuclear cells. Thereafter, sequential increases in the myeloblast-promyelocyte and myelocyte compartments of the marrow at 24 to 48 hours, respectively, suggested a wave of differentiation from a precursor compartment with subsequent maturation. The data suggest that intermittent endotoxemia may be ...
243 citations
TL;DR: It was found that many insertions which often arise as strongly polar mutations consist of only a few “foreign” DNA sequences.
Abstract: It was found that many insertions which often arise as strongly polar mutations consist of only a few “foreign” DNA sequences. The most commonly observed “short” polar IS1 insertions are all comprised of the same DNA with a duplex length of 750±80 nucleotide pairs. This insertable IS1 DNA can be integrated with either orientation into the genome at various positions in the lac and gal operons of E. coli; however, the inserted sequence is not permuted. The r14 polar insertion in gene cII of phage λ also consists of the same IS1 DNA (Hirsch et al., 1972 b). “Long” insertions (1170 to 1490 nucleotide pairs) were detected in the lac (IS3) and gal (IS2, IS4) operons and in the y and P-Q regions (IS2) of the λ genome and measured as single-strand loops in the l/r heteroduplex DNA. The insertions in the latter two positions are homologous, although those found in the P-Q region do not exhibit any obvious polarity.
190 citations
TL;DR: The anatomy of the prepared canal was very dissimilar to the instruments used to prepare them, especially in the apical third, and standard instrumentation techniques tend to leave a considerable portion of the canal wall untouched.
178 citations
TL;DR: Hyperthyroidism developed during and after iodide administration in four of the eight patients with nontoxic goiter in Boston, suggesting that the homeostatic mechanism controlling thyroid hormone synthesis and release in these patients is not functioning normally.
Abstract: The syndrome of iodide-induced hyperthyroidism (Jodbasedow) is not common and has been reported to occur in patients with iodine-deficient goiter after iodide replenishment. As part of a larger study to assess the effects of iodide administration on thyroid hormone synthesis in normal subjects and in patients with various underlying disorders of the thyroid, iodides (5 drops of a saturated solution of potassium iodide) were administered to eight patients with nontoxic goiter residing in Boston, an area of iodine sufficiency. Hyperthyroidism developed during and after iodide administration in four of the eight — an unexpectedly high frequency. This finding suggests that the homeostatic mechanism controlling thyroid hormone synthesis and release in these patients is not functioning normally. We recommend that large doses of iodides not be administered to patients with nontoxic goiter.
161 citations
TL;DR: Noninvasive polygraphic recordings were carried out and interpreted independently in 26 ambulatory patients with chronic alcoholism and no clinical evidence of heart disease, normal control subjects matched for age and sex, and 12 patients with alcoholic cardiomyopathy.
Abstract: To determine whether cardiac malfunction in chronic alcoholics precedes clinical signs of cardiac damage, noninvasive polygraphic recordings were carried out and interpreted independently ...
155 citations
TL;DR: It is proposed that the feedback loops controlling the immune response prevent activation of oncogenic viruses in transformed lymphocytes, and the relationship between malaria and lymphomas is presented.
138 citations
TL;DR: Four insertion sites in the omega region of gene z were identified and the position of the lac5 substitution and the SR2 deletion in the λplac DNA were determined by heteroduplex mapping.
Abstract: Several strongly polar mutations in the omega region of the z gene of the lac operon result from insertions consisting of only two specific sequences of DNA, one about 870 and the other 1170 nucleotide pairs long (based on single-strand measurements). No sequence homology was detected between the shorter (IS1) and longer (IS3) insertions. The IS1 insertion was shown to possess a specific attachment site, but it can be inserted with either orientation at several sites in the z gene. Four insertion sites in the omega region of gene z were identified and the position of the lac5 substitution and the SR2 deletion in the λplac DNA were determined by heteroduplex mapping.
TL;DR: The phagocytosis stimulating peptide present in γ-globulin has been isolated and its amino acid sequence shown to be L-threonyl-L-lysyl- L-prolyl- l-arginine, which was synthesized by the solid phase technic.
TL;DR: It was proposed that the histochemical demonstration of the isoenzyme in the bone marrow, liver, or spleen can be used as a diagnostic criterion for leukemic reticuloendotheliosis, thus differentiating it from lymphosarcoma and reticulum cell sarcoma.
Abstract: Histochemical study of the tartrate‐resistant acid phosphatase isoenzyme was made on frozen sections of surgical specimens from leukemic reticuloendotheliosis. The tumor cells of this disease were found to have strong tartrate‐resistant enzyme activity. Control studies on preparations of malignant lymphoma, other hematologic disorders, neoplasms of nonhematopoietic organs and normal tissues showed very little isoenzyme activity. Exceptions were found in specimens involved by Hodgkin's disease and in an adrenal of one patient with aldosteronism. It was proposed that the histochemical demonstration of the isoenzyme in the bone marrow, liver, or spleen can be used as a diagnostic criterion for leukemic reticuloendotheliosis, thus differentiating it from lymphosarcoma and reticulum cell sarcoma.
TL;DR: Four patients with pyoderma gangrenosum were found to have an abnormality of delayed hypersensitivity that was characterized by cutaneous anergy and dissociation between macrophage inhibitory factor production and blastogenic response in vitro.
Abstract: Four patients with pyoderma gangrenosum were found to have an abnormality of delayed hypersensitivity that was characterized by cutaneous anergy and dissociation between macrophage inhibitory factor production and blastogenic response in vitro. Three of these four patients had a rheumatoid-like polyarthritis. One patient responded to conservative therapy but three required high doses of corticosteroids for healing of the ulcers.
TL;DR: The mechanism of inhibition by l-homoarginine of human liver and bone alkaline phosphatase isoenzymes has been investigated and it was found that the mechanism was "uncompetitive."
TL;DR: A multiple regression analysis of composite values gives strong support to the hypothesis that cigarettes are a major source of cadmium to man and, in addition, can contribute more to the total body burden than the amount derived from other sources.
TL;DR: It is concluded that the combination of thrombocytosis and marked abnormality of platelet function is associated with a high risk ofThrombotic and hemorrhagic complications.
TL;DR: In this paper, it was shown that secondary nucleation does not involve a singular mechanism but that different kinds of secondary nucleations can take place under different conditions of supersaturation, liquid velocity, and impurity concentration.
TL;DR: Nerve fiber analysis showed a loss of fibers between proximal and distal segments of the nerve, with the heaviest losses in the smallest caliber fiber sizes.
Abstract: Clinical problems in obtaining complete anesthesia after inferior alveolar nerve block have prompted this study of mylohyoid nerves in humans as a possible source of secondary innervation of the mandibular posterior teeth. Nerve fiber analysis showed a loss of fibers between proximal and distal segments of the nerve, with the heaviest losses in the smallest caliber fiber sizes. These unmyelinated and finely myelinated fibers are largely responsible for mediation of pain sensation, and their presence in the mandibular posterior tooth region could help to explain alternative pathways for pain after inferior alveolar nerve block has failed to give complete anesthesia.
TL;DR: Results suggest that higher concentrations of local anesthetic agents are more generally histotoxic than previously thought, and preferential destruction of red- or white-type muscle fibers was observed after many of the agents.
TL;DR: It is revealed that at this early period in language development children already use the interrogative form analogously to their mothers for making suggestions and reports, and it is the embeddedness of verbalizations in a particular personal relations, action context which fosters this development.
Abstract: A classification of interrogatives according to their purposes was devised and applied to four, 100-utterance samples by three mothers to their children when their children had a mean utterance length of (1) two morphemes and (2) four morphemes. The distribution of mothers' utterances into interrogative and noninterrogative types and into the classification of interrogatives by purpose was obtained. Interrogatives comprise from 15 to 33% of mothers' utterances and interrogatives whose purpose is not to ask questions but rather to make suggestions, negative evaluations of the child's behavior, or to make reports occur with all mothers. A study of these mothers' children's interrogatives in the three-morpheme period revealed that at this early period in language development children already use the interrogative form analogously to their mothers for making suggestions and reports. An analysis of the development of this capacity based on the concept of the "speech act" is given which leads to the conclusion that it is the embeddedness of verbalizations in a particular personal relations, action context which fosters this development.
TL;DR: Conduction of action potentials in the nerves of certain bivalve molluscs continues after prolonged exposure to high concentrations of tetrodotoxin (TTX) and saxitoxin (STX) while nerves of other species are blocked.
TL;DR: Criteria were discovered for identifying the tanycyte process as it courses through the arcuate neuropil, making it possible to describe the entire ependymal cell from the apical surface to the end foot.
Abstract: The ependymal tanycytes of the third ventricle at the level of the arcuate nucleus were studied with the electron microscope. Criteria were discovered for identifying the tanycyte process as it courses through the arcuate neuropil, making it possible to describe the entire ependymal cell from the apical surface to the end foot. The apical membranes of the tanycytes are characterized by a lack of cilia and by numerous microvilli. The apical lateral membranes may be extensively interdigitated, and the junctional complexes between adjacent apical lateral membranes often lack maculae occludentes. The cells are well endowed with large Golgi apparatus. The endoplasmic reticulum is principally smooth. The tanycyte processes contain small paraxially oriented mitochondria and numerous paraxial microtubules as well as lipid droplets and accumulations of smooth endoplasmic reticulum in the form of concentric rings. Some of the tanycytes end on capillaries in the arcuate nucleus. These pericapillary ependymal sheaths contain irregular inclusions of varying densities. The ependymal tanycytes have been implicated as secretory cells involved in hypothalamic control of the anterior pituitary gland. This concept is discussed in relation to the present fine structural findings.
TL;DR: The pharmacological results do not strongly indicate a role of cyclic AMP but are generally consistent with the hypothesis that cyclicAMP may mediate relaxation of catch.
TL;DR: Double-stranded RNA from Sindbis virus-infected chick, hamster, and mosquito cells was characterized in sucrose gradients by immunochemical methods using antibodies specifically reactive with multistrand polyribonucleotides and radioactively labeled ds RNA.
TL;DR: The serum isoenzyme level of alkaline phosphatase observed an exponential course as a function of gestation time and the highest level coincided with delivery in half of the patients and in the others, it preceded delivery.
Abstract: By means of a convenient automated method, the placental isoenzyme of alkaline phosphatase in pregnancy serum has been measured in 162 normal pregnancies. The basis of this measurement is, first, the heat inactivation of the nonplacental isoenzyme, and then the measurement of activity (substrate; phenylphosphate) under conditions of pH and substrate concentration which favor the action of the placental isoenzyme. Conditions for a manual method for measuring the placental isoenzyme are also given. The serum isoenzyme level of alkaline phosphatase observed an exponential course as a function of gestation time. The highest level coincided with delivery in half of the patients and in the others, it preceded delivery. On the basis of these normal data, it is now possible to recognize a deviation from the normal curve. The possible significance of the serum placental isoenzyme of alkaline phosphatase is discussed.
TL;DR: The present article advances a general hypothesis to explain one underlying basic abnormality leading to the development of IgE-mediated human atopic allergy.
Abstract: Atopic allergy has long been recognized as a disease of immunologic origin. Most immunologists and allergists would now agree that the symptom complex seen in uncomplicated allergic rhinitis and bronchial asthma is in large part attributable to the activity of pharmacologic intermediates either released from mast cells or formed in vivo as a consequence of specific antigen-antibody interactions. These interactions involve a highly specialized and extraordinarily active antibody of a newly defined immunoglobulin class (IgE) (Ishizaka & Ishizaka, 1966,1968; W.H.O., 1968) which has the capacity to sensitize cells for long periods of time for the subsequent triggering action of antigens. Immunoglobulin E is a normal constituent of human serum which is present at 1/40,000th the concentration of immunoglobulin G (Johansson, 1967). Recent studies suggest that IgE may be significantly increased in patients with atopic allergy (Johansson, 1967; Berg & Johannson, 1969; Schwartz & Buckley, 1971a; Kumar, Newcomb & Hornbrook, 1971; Yunginer & Gleich, 1971; HogarthScott et al., 1971) and that IgE levels rise with seasonal allergen exposure. It may be elevated as well in many other diseases, among which are severe liver disease, hypersensitivity aspergillosis, coehac disease, visceral larva migrans, ascariasis, pulmonary haemosiderosis and rare forms of infectious disease (Buckley, Wray & Belmaker, 1971; Heiner & Rose, 1970; Johansson, Mellkin & Vahlquist, 1968). However, it has never been clearly understood why the specific antibodies of this class, which react with air-borne antigens and are responsible for the symptoms of hay fever and asthma, appear in only certain individuals exposed to these antigens. The present article advances a general hypothesis to explain one underlying basic abnormality leading to the development of IgE-mediated human atopic allergy.
TL;DR: It is concluded that DTIC is the best agent for the therapy of melanoma with an expected response rate of 20%, and that its combination with BCNU does not add to its therapeutic effectiveness except in patients with central nervous system metastases.
Abstract: One hundred twelve evaluable patients with metastatic malignant melanoma were randomized to receive either a combination of DTIC 100 mg/m2/day × 5 days and BCNU 75 mg/m2/day × 2 days or DTIC 150 mg/m2/day × 5 days alone. The combination treatment yielded 12/61 responders as compared with 9/51 with DTIC alone. Responders survived significantly longer (7 months) than did nonresponders (3 months). Toxicity of both treatments was tolerable, but more frequent bone marrow suppression was encountered with DTIC-BCNU combination. Patients were analyzed for relation between survival and the following: regional node dissection, length of the free interval, and positive urinary melanogens. Only the latter relation tended to be positive. We conclude that DTIC is the best agent for the therapy of melanoma with an expected response rate of 20%, and that its combination with BCNU does not add to its therapeutic effectiveness except in patients with central nervous system metastases.