Proton-stimulated opening of stomata in relation to chloride uptake by guard cells

The concentration of potassium chloride required in the incubation medium to open stomata in isolated epidermal tissues of Commelina communis L. and Vicia faba L. could be lowered from 100 mM to 10 mM if the proton concentration of the ambient solution was increased from pH 5.6 to pH 3.5. This acidification effect was formerly attributed to the destruction of epidermal and subsidiary cells resulting in a relief of back pressure upon guard cells. While guard cells remain viable at pH 3.5, as demonstrated by their susceptibility to inhibition by uptake of glucose or to uncoupling by DNP, incipient destruction of the cells surrounding them could first be observed 30 min after the onset of the incubation experiment. By this time, however, the stomata had already opened; the time course of stomatal opening at pH 3.5 did not show any lag phase corresponding to the time required for damaging epidermal cells and showed no difference to that at pH 5.6 Thus, the acid-stimulated opening of stomata appears to be a biphasic phenomenon consisting of a physiologic effect onto which the physical effect of the relief of back pressure is superimposed over longer periods of incubation. To interpret the physiologic role of an increased proton concentration in the ambient solution of isolated epidermal strips, it is suggested that guard cells take up protons and chloride ions in an electroneutral symport. While protons are extruded again to generate the negative membrane potential required for potassium influx, chloride ions are retained to maintain electroneutrality.

[Modulation of humoral immunity in the mouse by means of grafts carrying reticulated polysaccharides]

Synthetic reticulated polysaccharides grafted with linear amino-acids or amines have been submitted to the test of localized hemolysis in gel (Jerne). Some of them show a statistically highly significant immuno-stimulating power in Mice.

A cytogenetic survey of an institution for the mentally retarded. II. C-band chromosome heteromorphisms

Heteromorphisms of chromosomes 1, 9, and 16 were studied by C-banding in a population of 403 mentally retarded individuals from diverse ethnic groups. A significant difference in the distribution of heteromorphisms was found among the different racial groups. The Orientals had a larger C-band on chromosome 1 and a smaller C-band on chromosome 9 than the other racial groups while the Caucasians had a larger C-band on chromosome 9. The Oriental group also had a significantly greater proportion of inverted C-bands. No differences were found in the distribution of C-band heteromorphisms among different etiologic categories of mental retardation.

Inversions and other unusual heteromorphisms detected by C-banding

Sixteen patients with unusual heteromorphisms involving alterations of the length and/or position of centromeric heterochromatin are described. Family studies showed that the heteromorphisms were present in other relatives and segregated in the expected 1:1 ratio. There was a significantly greater frequency of unusual heteromorphisms among Orientals than in other races studied.

Identification of young megakaryocytes by immunofluorescence and cytophotometry

The DNA-content of fluoresceine-labeled platelet antigen containing cells of mouse bone marrow was measured. For immunofluorescence highly specific anti-mouse-platelet-serum and fluoresceine-conjugated antigammaglobuline was used, applying the "sandwich" technique. Three hundred panoptically identifable megakaryocytes served as control group. The DNA-polyploidization pattern of megakaryocytes and immunofluorescence positive cells was almost identical. However, among the immunofluorescence positive cells a considerable amount of cells showed DNA-values lower than 4c, whereas the megakaryocytes of the Pappenheim stained smears revealed no DNA-values lower than 4c. The percentages of diploid and tetraploid cells, respectively, was 6 and 7% compared with 0 and 1% of panoptically identifiable megakaryoctyes. The results suggest that young megakaryocytic cells with diploid and tetraploid DNA-values can be detected by immunofluorescence technique, indicating that the flow from the uncommited to the committed megakaryocytic precursor cell appears at this early stage of megakaryocyte production.

Effect of endocrine manipulations on glucocorticoid binding capacity in rat skeletal muscle

[3H]Dexamethasone binding capacity in rat muscle cytosol was determined after various endocrine manipulations in an attempt to identify factors which might regulate the level of the cytoplasmic hormone receptor protein. Hypophysectomy and adrenalectomy markedly increased the specific binding of [3H]dexamethasone in skeletal muscle cytosol, while implantation of the MtT tumour which secretes ACTH and growth hormone, as well as treatment with glucocorticoids reduced the glucocorticoid specific binding. Since the effects of hypophysectomy and the MtT tumour depend on the presence of the adrenals, they appear to be mediated via changes in circulating glucocorticoid level. Alloxan- or streptozotocin-induced diabetes caused only a slight reduction in the binding of [3H]dexamethasone in muscle, suggesting that the enhanced responsiveness to glucocorticoids in diabetes is not due to increased glucocorticoid receptor activity. There is a sex-dependent effect on binding, female rats having a higher concentration of binding sites. Furthermore, treatment with the synthetic androgen fluoxymesterone or with glucocorticoids reduces binding, while oestradiol-17β enhances it.

The changes in glucocorticoid binding capacity induced by the various endocrine manipulations appear to reflect mainly changes in receptor concentration rather than occupancy, since the binding assays were preformed after a suitable time allowance for removal of the administered hormones by metabolism.

Platelet size distribution in mice following immunothrombopenia and vincristine administration

In the present study platelet size distribution was investigated after induction of immunothrombocytopenia by rabbit-anti-mouse-platelet-serum (RAMPS) and after vincristine-induced thrombocytopenia. The platelet size distribution after a single dose of RAMPS showed a shift to larger volumes at day 1 and 2, and a decrease to slightly smaller volumes than normal at day 8. These differences, however, were not statistically significant. After vincristine administration, a dose-dependent increase of the platelet size distribution was demonstrated, which lasted from day 1-7. It is suggested that in immune-induced thrombocytopenia the young platelets released from bone marrow megakaryocytes are not exclusively large platelets. On the other hand the early appearance of large platelets after vincristine administration points to a toxic or segregating effect of vincristine on circulating platelets. Therefore, in our experiments, the platelet size is not suitable for the differentiation of young and old platelets.

Increases in steroid binding globulins induced by tamoxifen in patients with carcinoma of the breast

The effects of tamoxifen on cortisol binding globulin (CBG) and sex hormone binding globulin (SHBG) were studied in 25 women and one man with breast cancer. These patients were in various endocrine states according to age (15 post-menopausal women) or previous endocrine surgery (ovariectomy, two patients; ovariectomy plus adrenal surgery, five patients; hypophysectomy, three patients; ovariectomy plus hypophysectomy, two patients). The administration of tamoxifen (20-40 mg/day) resulted in increases in the level of CBG in all patients (mean rise in binding capacity 10.8 microgram cortisol/100 ml plasma) and in the level of SHBG in 21 patients (mean rise in binding capacity 0.79 microgram dihydrotestosterone/100 ml plasma for all patients). These increases were positively correlated. They were not associated with any alteration in the association constants of the steroid binding globulins. The effect of tamoxifen on CBG diminished with increasing age. The changes in the levels of CBG and SHBG were independent of the endocrinological state of the patient. It is inferred that tamoxifen has a direct oestrogen-like action on the liver which results in increased production of CBG and SHBG. Tamoxifen therapy for carcinoma of the breast appeared to be least effective in those patients in whom the drug caused the highest increase in the concentration of CBG.

Inhibition of stomatal opening during uptake of carbohydrates by guard cells in isolated epidermal tissues

The uptake of glucose and other carbohydrates into the guard cells of Commelina communis L. was found to inhibit the opening of the stomata. The concentration of glucose necessary to achieve about 50% inhibition was of the same order of magnitude as the potassium concentration required for opening; the uptake systems for potassium and glucose appear to be competitive and to exhibit the same degree of affinity. It is suggested that the uptake of glucose occurs via a proton cotransport, which, depolarizing the membrane potential, slows down the electrogenic import of potassium ions. The process of stomatal closure, in contrast, appears not to be affected by carbohydrate uptake. In guard cells of Tulipa gesneriana L. and Vicia faba L., which do not possess subsidiary cells, import of glucose or other carbohydrates did not interfere with the regulation of stomatal movements.

A cytogenetic survey of an institution for the mentally retarded: I. Chromosome abnormalities

A cytogenetic survey of 475 patients in an institution for the mentally retarded is reported. The chromosomes of all patients were studied using both a non-banding and a G-banding technique in order to estimate the relative efficiency of the two technique in detecting structural rearrangements of the chromosomes. A total of 57 patients was found to have a chromosome abnormality, including five with a balanced structural rearrangement. The contribution of chromosome aberrations to the etiology of mental retardation is discussed with special emphasis on the contribution of balanced structural rearrangements.

Megakaryocyte polyploidization in May-Hegglin anomaly

Polyploidization of megakaryocytes was studied in bone marrow aspirates from 3 patients with May-Hegglin anomaly by combined application of cytophotometric determination of the DNA content and autoradiography with 3H-TdR labeling in vitro. A marked elevation of the influx of progenitor cells into the megakaryocytic cell system as well as a decreased maturation capacity from type II to type III megakaryocytes was observed possibly contributing to the pathological platelet sequestration. The polyploidization activity as assessed by 3H-TdR labeling and nuclear DNA content was normal.

Structural chromosome abnormalities in Down syndrome: a study of two families

Two families were ascertained through a proband with Down syndrome and a structural rearrangement involving two chromosomes 21. It is suggested that in one patient the chromosome is an isochromosome formed by misdivision of the centromere of a maternal telocentric chromosome 21 and that in the other a Robertsonian translocation involving chromosome 21 was inherited from the mother, who is a 46,XX/46,XX, -21,+t(21q21q) mosaic. The origin of the mosaicism is discussed and considered to be likely to be the result of breakage and reunion at the chromatid, rather than the chromosome, level.

A topographic approach to breast cancer: the relation of topographic and mammographic findings

One hundred and twenty-eight patients with breast cancer who, on the basis of mammographic study, were treated by mastectomy were analyzed. The purpose of this endeavor was to correlate the roentgenologic features with the pathologic findings. The correlation between them was very good: the type of tumor opacity, the microcalcifications, and the various other radiologic patterns were compatible with both localized and extensive breast cancer. Mammography appears to be valuable in the selection of patients suitable for conservative treatment.

A new topographic approach to the spread of breast cancer: the grid method

In a series of 181 patients with breast cancer treated by mastectomy with axillary lymph node dissection, the authors developed and used an improved topographic technique, which they call the "Grid Method", which maps out the extent of a given cance of the breast. Three types of tumor spread are defined: Type 1, limited (L)(31%); Type 2, multifocal (M)(13.2%); and Type 3, extensive (E)(55.8%). This topographic information allows a more accurate assessment of prognosis when used in conjunction with the morphologic findings. Moreover, the topographic "Grid" study is simple to perform and easy to assess. Of prime importance is the relationship between the topographic and mammographic findings.

Proliferation characteristics of erythroblasts in chronic renal failure

Proliferation of bone marrow erythroblasts in patients with chronic renal disease was studied by combined application of cytophotometric measurement of the DNA content and 3H-TdR labeling in vitro. A striking decrease of 3H-TdR labeling was found in most of the cases. The proportion of diploid (G0 + G1) as well as of tetraploid unlabeled cells (G2) was increased. The data suggest a disturbed induction of DNA synthesis of resting cells as well as an arrest of cells in G2 being responsable for ineffective cell production in this disease.

[Comparative study on x-ray and scintigraphie pictures and blood gases in sarcoidosis (author's transl)]

Scintigraphic examination of the lungs in sarcoidosis has been used as a supplement method of the functional examination. Perfusion scintigraphy enables to locate places with lowered regional perfusion in the form of spotted fall outs. In some cases of hilar lymphonodular forms of sarcoidosis we can already find some diffuse spotted fall outs of perfusion even if parenchymatous changes are still not visible. Up to now we have not seen any lobar or alar fall outs of radioactivity, as they can be found in central types of bronchogenic carcinoma. In sarcoidosis with micro- or macronodular X-ray shadows the scintigraphic defect in its extent sometimes does not correspond to these changes. On the basis of our material the mutual relation between scintigraphic pictures on one hand and blood gases on the other hand could not been neither confirmed nor eliminated.

In vivo labeling of platelets with 75Se -- selenomethionine in patients with hepatic cirrhosis and thrombocytopenia

Labeling of platelets in vivo by 75Se -- Selenomethionine (75Se-M) was performed in nine cases of hepatic cirrhosis and thrombocytopenia for evaluation of the kinetics of platelet maturation. Folic acid and vitamin B12 deficiency was excluded by pretreatment of the patients with these agents. The platelet maturation time -- time between the injection of the isotope and maximum radioactivity of separated blood platelets -- was shortened to 7.7 +/- 1.1 days (mean +/- SD) compared to the normal 9.1 +/- 1.4 days. For explanation a disturbance of megakaryocyte maturation and/or platelet release from the bone marrow is suggested.

In vivo study of platelet kinetics by 75Se-methionine in different haematological disorders

Labeling of platelets in vivo by 75Se-methionine was performed in premalignant and malignant haematological disorders for evaluation of the kinetics of platelet maturation. The "normal" platelet maturation time (time between the injection of the isotope and maximum radioactivity of separated blood platelets) in eight non-haematological patients showing normal platelet counts was 9.1 days. A shortening of platelet maturation time of 5-7 days was observed in three of four cases with panmyelopathy (high bone marrow cellularity), in three of four cases with malignant lymphatic disorders (multiple myeloma, chronic lymphocytic leukaemia, lymphosarcoma), and in two of four cases with myeloproliferative syndromes. No correlation to the peripheral platelet counts was observed. For explanation of the premature platelet release from the bone marrow a disturbance of the megakaryocyte maturation is suggested.

[Glycoside induced intestinal ischemia. Therapeutic possibilities (author's transl)]

Intestinal infarction in the absence of organic vascular occlusion received increasing attention in recent years. There is strong evidence from experimental work and clinical observations that cardiac glycosides may play an important role in the pathophysiology of this disorder. Our experiments using the so called mechanical ventricular massage confirm this theory. We could demonstrate that the decrease in mesenteric arterial perfusion following the i.v. administration of ouabain is caused by extracardiac effects of the glycoside on vascular smooth muscle. The Ca++ -antagonistic compound (Verapamil) blocks and reverses the Ca++-synergistic action of the glycoside independent of the time of injection.

Acrocentric chromosome associations in man

Heterogeneity among chromosomes was found to be a highly significant source of variation for association proportions, while culture, slide, and observer were negligible sources of variation for association proportions although important for numbers of associations. The consequences of these results for tests of group differences are discussed. It seems evident that each pair of acrocentric chromosomes has its own characteristic probability of entering into association. This is presumably a combination of the probability for each individual member of the pair, a proposition easily tested utilizing acrocentric chromosomes carrying polymorphisms which allow each member of the pair to be individually recognized. A mathematical theory for pairwise satellite association was developed and shown to fit observations on banded chromosomes. While we found very significant heterogeneity among individuals in the frequency with which different chromosomes entered into associations, there was no significant evidence for preferential association between any particular chromosomes, either heterologous or homologous. This finding in our material of apparently random associations between different chromosomes is contrary to claims made by other investigators and should be tested on other material. No correlation was found between the phenotype of the chromosome, as judged by cytogenetic polymorphisms, and its probability of association.

Multifocal glioma of the brain. Case report

A case is presented in which two separate concurrent astrocytomas of the brain in the same patient were successfully operated on. The patient has been followed for 3 years and remains well. The authors believe that the diagnosis of multifocal tumors can be established on clinical grounds when the tumors are remote from each other, and when there has been no recurrence of neoplasm between the lesions after a long follow-up period. It is felt that a more optimistic approach to the treatment of multifocal tumors may yield good results.

Interaction of glucocorticoid hormones with rat skeletal muscle: catabolic effects and hormone binding

The mechanism of action of glucocorticoid hormones on rat skeletal muscle was studied by following their effect on muscle weight, free amino acid content, activity of amino acid-metabolizing enzymes, and binding to cytoplasmic receptor proteins. A significant reduction of gastrocnemius muscle and body weight occurred following administration of cortisol, triamcinolone diacetate, and triamcinolone acetonide to adrenalectomized rats. Treatment with triamcinolone diacetate also reduced the level of several free amino acids and enhanced the activity of a myofibrillar protease in skeletal muscle. The hormone had, however, no effect on the activity of various enzymes involved in amino acid catabolism in muscle. In nephrosis, another condition of muscle wasting, the level of several muscle amino acids were also reduced to a lesser extent. Cortisol and triamcinolone acetonide, both of which induce muscle wasting, were found to bind to two distinct cytoplasmic proteins in muscle. Binding of the labeled hormones was followed at 0 C and could be observed in presence of a 1000-fold excess of the catabolically inactive steroid epicortisol. Binding of 3H-triamcinolone acetonide. In vitro competition experiments further suggest a correlation between steroid binding to the 3H-dexamethasone or 3H-triamcinolone acetonide site and their potency to induce muscle catabolism. It is concluded that skeletal muscle is a direct target organ for glucocorticoids, and that muscle responsiveness involves binding of the active hormones to cytoplasmic receptor sites.

The valve of chemotherapy in the treatment of testicular dysembryoplastic tumors

Chemotherapy appears to be of help in treating dysembryoplastic testicular tumors. It seems better to treat first by surgery (lymphadenectomy) if possible, then (a) if no nodes are involved or only one has been discovered by microscope examination, with chemotherapy for one year; or (b) if two or more nodes are involved, with irradiation of the nodes and chemotherapy. Even if lymphadenectomy is not possible, one course of chemotherapy followed by cobalt and more chemotherapy can bring results in some cases.

Proliferation characteristics of lymphoid cells of human bone marrow in health and in chronic renal failure

Proliferation of bone marrow lymphoid cells of 8 healthy subjects and 7 patients with chronic renal insufficiency was compared using the cytophotometric measurement of the DNA content combined with 3H-thymidine labelling in vitro. In renal insufficiency the cells showed a marked decrease of the proliferation activity. This is apparent from the impaired labelling indices and accumulation of diploid and unlabelled cells. The data suggest that the lymphoid cell proliferation is affected by the same pathophysiological mechanism as that leading to impairment of red cell production. By subclassification according to cytoplasmic basophilia, this proliferation disturbance could be related to the basophilic and not to the pale type of lymphoid cells.

Membrane-bound enzymes. III. Protease activity in leucocytes in relation to erythrocyte membranes

Protease activity was detected in membranes of human bovine erythrocytes prepared by the conventional procedures which include washing and removal of the "buffy layer". The enzyme was extracted by 0.75 M KCNS or (NH4)2SO4 and was activated by 0.4 to 0.5 M of the same salts. Colored, particulate hide powder-azure, membrane fractions and soluble proteins such as hemoglobin, casein or albumin were susceptible to hydrolysis by the membraneous protease. Partial purification of the enzyme was accomplished through disc-gel electrophoresis on polyacrylamide in the presence of 0.25% positively charged detergents like cetyltrimethylammonium bromide. An alkaline protease (pH 7.4) with properties similar to those of the erythrocyte enzyme was found in leucocytes. The similarity between the properties of the leucocytic and erythrocytic proteases and the correlation of the activity in erythrocyte membranes with content of white cells in these preparations, suggest that enzymatic activities in the contaminating leucocytes are responsible for the activity of membraneous proteases in erythrocytes.

Interaction of anabolic steroids with glucocorticoid receptor sites in rat muscle cytosol

While glucocorticoid hormones act catabolically on skeletal muscle through their binding to glucocorticoid-specific receptors in the cytosol, androgens exert anabolic responses but no androgen-specific binding proteins could be detected in this responsive tissue. However, various nonradioactive androgens were effective in displacing labeled dexamethasone or cortisol from their respective cytoplasmic receptors in muscle, both in vitro and in vivo. The inhibition of glucocorticoid binding by androgens is competitive, and could be observed following a single or repeated administration of the androgens to adrenalectomized-castrated animals. The synthetic androgen fluoxymesterone and the hormone testosterone displayed Ki values of 7.5 X 10(-6) M and 1 X 10(-5) M, respectively, for the inhibition of [3H]dexamethasone binding in muscle cytosol. On the basis of competition experiments it is postulated that interaction of androgens with glucocorticoid receptors prevents the binding of glucocorticoids and might be responsible in part for the anabolic effects of pharmacologic doses of androgens in muscle.

Cortisol binding in rat skeletal muscle

Studies of the reversible binding of [3H]cortisol by rat gastrocnemius muscle cytoplasm in vitro reveal specific binding in the 27,000 times g supernatant fraction at 0 degrees. The [3H]cortisol-binding molecule had an apparant Kd value of 1.7 times 10-7 M and the number of binding sites was 0.99 pmol per mg of cytosol protein. Only a single class of [3H]cortisol-binding sites could be detected, whose protein nature was suggested by its susceptibility to nagarse. The [3H]cortisol-protein complex sedimented at similar to 4 S in a 5 to 20% sucrose gradient either in the presence or absence of 0.3 M KCl. Binding increased more than 2-fold in adrenalectomized rats and was markedly reduced in the muscle of rats pretreated with cortisol. In contrast to the binding of [3H]dexamethasone and [3H]triamcinolone acetonide to receptor proteins in muscle, no correlation was found between the ability of various steroids to complete wtth [3H]cortisol binding and their glucocorticoid potency: [3H]cortisol binding was inhibited by a 1000-fold higher concentration of unlabeled cortisol and progesterone but not by dexamethasone or triamcinolone acetonide. It is therefore suggested that the [3H]cortisol-binding reaction is not directly involved in the biological effects of all potent glucocorticoids in skeletal muscle. The [3H]cortisol-binding protein in muscle cytosol could not be unequivocally distinguished from rat plasma corticosteroid-binding globulin, because both had similar steroid specificity and temperature stability, were not markedly affected by--SH reagents, and displayed similar sedimentation properties.