Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011570 (depression)
 172,036 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Ram "rete testis" fluid (RTF) routinely collected throughout the year has been used as a source of inhibin. The mean flow rate and mean concentration of spermatozoa in the fluid remained constant during the first 12 days of cannulation. More than 50 castrated or cryptorchid rams have been treated with low doses of steroid-free RTF over a 25-h blood sampling period. Human serum albumin was injected as a control. RTF depressed both FSH and LH plasma levels although the pattern was different for each hormone. There was no change in prolactin secretion. LH secretion was affected first while FSH remained unchanged in castrated and in cryptorchid rams. Thereafter, the maximum depression of FSH plasma levels occurred at a time when LH started to return or had returned to preinjection levels in the cryptorchid and castrated animals respectively. In the cryptorchid rams, RTF suppressed pulsatile LH secretion which was present before treatment but in the castrated animals, RTF lowered LH plasma levels which were constant and showed no pulsatile changes before treatment. Both FSH and LH inhibitory activities have been found in all active fractions obtained by purification of RTF. These activities are papain-sensitive and active fractions have a high apparent molecular weight (greater than or equal to 100 000) as shown by gel filtration and ultrafiltration. These and other results in the literature have lead to a re-definition of inhibin as a protein factor of gonadal origin able to depress plasma levels of FSH and LH, even at low doses.
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PMID:Inhibin activity in ram rete testis fluid: depression of plasma FSH and LH in the castrated and cryptorchid ram. 4 91

B and T lymphocytes have been measured in 100 women--71 patients with breast cancer and 29 controls--using sheep-erythrocyte rosetting techniques. Compared with controls (healthy women or patients with benign breast disease), there is a highly significant depression of T-cell percentage in all stages of breast cancer except locally advanced (stage 3) disease. These stage-3 cases seem to constitute a biologically distinct group. T-cell percentages in early (stage 1) patients overlap with those seen in stages 3 and 4, raising the possibility that there are in stage 1 two subpopulations of T-cell values that are associated with differences in subsequent tumour progression. B-lymphocyte levels are similar in all groups. Low T-cell levels return to normal after incubation with papain in virto but fall again after resuspending the treated lymphocytes in autologous (cancer) serum. The results suggest that T-cell depression is due to a masking factor on the surface of some T lymphocytes which is also present in the serum of cancer patients, and removable by enzyme digestion.
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PMID:T and B lymphocytes in breast cancer stage relationship and abrogation of T-lymphocyte depression by enzyme treatment in vitro. 5 39

The ATPase activity of chicken gizzard myosin was studied by varying the KCl concentration in the reaction medium. The following was thus found: (a) A sharp depression of the activity occurred when the KCl concentration was reduced to less than 0.3 M, showing the minimum activity around 0.15 M KCl. (b) The activity depression was removed by addition of urea or bay papain-digestion, but not by addition of p-chloromercuribenzoate. (c) In the KCl concentration where the activity depression occurred, the ATPase reaction proceeded in two distinct phases; the activity was relatively high in the early phase of the reaction and declined into the later phase where the steady state reaction took place. (d) In the KCl concentrations higher than that particular concentration or in the presence of urea, the ATPase reaction proceeded in one phase. (e) The temperature dependence of the ATPase activity in the early phase was of an ordinary magnitude being approximately equal to that of the ATPase activity in 0.6 M KCl. In contrast, the temperature dependence of the activity in the later phase was unusually small. Gizzard myosin in various concentrations of KCl was also examined by measuring the turbidity and the light-scattering intensity, and by observation under an electron microscope. The following was thus found: (a) In the KCl concentration where the activity depression occurred, there was a stagnation in the turbidity decrease as the KCl concentration was gradually increased and also the formation of "thick filaments," each of which was approximately 0.6-0.9 micron in length and 20-30 nm in diameter with no central "bare zone." (b) Addition of ATP induced dissociation of the thick filaments, and the dissociation occurred during the early phase of the ATPaseeaction. (c) Moreover, the temperature dependence of the ATP-induced dissociation rate was approximately equal to that of the ATPase activity in the early phase. On the basis of the findings mentioned above, it is concluded that the activity depression results from the ATP-induced dissociation of myosin filaments. Moreover, since high concentrations of KCl or urea also caused dissociation of myosin filaments and yet did not produce the activity depression, it was strongly suggested that gizzard myosin in the ATP-dissociated form must be different from that in the urea- or KCl-dissociated form, probably in the physical state of some myosin aggregates which were not detectable by the physical methods we used. As a side-observation, gizzard myosin filaments formed in the presence of ADP were found to be unusually long (longer than 2 micron), and they looked very similar to the particular filaments of skeletal myosin that were reported, by Moos, to be formed in the absence of the C protein.
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PMID:Adenosine triphosphatase activity and "thick filament" formation of chicken gizzard myosin in low salt media. 14 68

Myosin and subfragment-1 were prepared from rabbit hearts hypertrophied secondary to pulmonary artery constriction. The Ca2+ -stimulated ATPase activity was reduced while the potassium/EDTA-stimulated ATPase activity was unchanged in both the myosin and subfragment 1 (S-1) from hypertrophied hearts. When hypertrophy myosin was mixed with an equal quantity of control myosin, the ATPase activity of the mixed protein fell halfway between control and hypertrophy values. Similar results were obtained with control and hypertrophy S-1. The actin-stimulated ATPase activity of hypertrophy S-1 was slightly depressed but unlike hypertrophy myosin this depression was not significant when compared to normal S-1. This suggests that papain cleavage may have removed part of the conformational difference that exists between control and hypertrophy myosins.
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PMID:The ATPase activity of subfragment-1 from the hypertrophied heart. 14 12

The relationship between tumour load and immunity in gastrointestinal cancer has been studied by sequential comparison in patients whose tumour has been removed and those whose tumour was found to be inoperable. Total lymphocyte count, absolute and percentage T- and B-lymphocyte counts, effect of papain on E-rosetting cell levels, and inhibitory effect of cancer sera on E-rosette formation by normal lymphocytes have been studied in 30 patients with stomach or colorectal cancer, and 10 control patients with benign gastrointestinal disease. The examination was done on each patient before and at regular intervals after operation up to 24 weeks. Operable cases, with removal of tumour load, showed a temporary fall in total lymphocyte count and T cell counts, which returned to normal by four weeks postoperatively. Inoperable cases (15 patients) showed a progressive fall in total lymphocyte count and a relatively greater depression of T cell counts, in parallel with increasing tumour mass. E-receptor blocking factor was demonstrated in the sera of cancer patients. This factor was related to tumour mass and presumably was of tumour origin, as it persisted in the inoperable group but disappeared by 12 weeks after tumour removal. The factor explained the excess depresion of T cells over total lymphocytes, but does not explain the continuing depression of total lymphocyte count in the cancer patients.
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PMID:Significance of tumour mass on T-lymphocyte levels in patients with gastrointestinal cancer. 31 23

A monoclonal antibody against subfragment 2 (S-2) of smooth muscle myosin, designated MM-9, was generated and characterized. MM-9 potently inhibited subfragment 1 (S-1) release by papain proteolysis of myosin, suggesting that the epitope of MM-9 is at or very close to the S-1/S-2 junction. The depression of Ca2(+)- and Mg2(+)-ATPase activities of myosin at low ionic strength was significantly reduced by MM-9. MM-9 increased the acto dephosphorylated HMM ATPase activity about 3-fold. On the other hand, the antibody had no effect on the KCl-dependence of viscosity of monomeric myosin. These results suggest that the folding of the myosin rod is not the direct determinant of enzymatic activity, and that the subtle conformational change at the S-1/S-2 junction (head-neck region) plays a critical role in determining enzymatic activities.
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PMID:Alteration of the enzymatic properties of smooth muscle myosin by a monoclonal antibody against subfragment 2. 169 93

Monoclonal antibodies against gizzard smooth muscle myosin were generated and characterized. One of these antibodies, designated MM-2, recognized the 17-kDa light chain and modulated the ATPase activities and hydrodynamic properties of smooth muscle myosin. Rotary shadowing electron microscopy showed that MM-2 binds 51 (+/- 25) A from the head-rod junction. The depression of Ca2+- and Mg2+-ATPase activities of myosin and Ca2+-ATPase activity of heavy meromyosin at low KCl concentration were abolished by MM-2. Viscosity measurement indicated that MM-2 inhibits the transition of 6 S myosin to 10 S myosin. While the rate of the production of subfragment-1 by papain proteolysis of 6 S myosin was inhibited by MM-2, the rate of proteolysis of the heavy chain of 10 S myosin was enhanced by MM-2 and reached the same rate as that of 6 S myosin plus MM-2. These results suggest that MM-2 inhibits the formation of 10 S myosin by binding to the 17-kDa light chain which is localized at the head-neck region of the myosin molecule. MM-2 increased the Vmax of actin-activated Mg2+-ATPase activities of both dephosphorylated myosin and dephosphorylated heavy meromyosin about 10- and 20-fold, respectively. MM-2 also activated the actin-activated Mg2+-ATPase activity of phosphorylated myosin at a low MgCl2 concentration and thus abolished the Mg2+-dependence of acto phosphorylated myosin ATPase activity. These results suggest that MM-2 inhibits the formation of 10 S myosin, and this results in the activation of actin-activated Mg2+-ATPase activity even in the absence of phosphorylation.
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PMID:Inhibition of conformational change in smooth muscle myosin by a monoclonal antibody against the 17-kDa light chain. 246 45

No distinct differences were noted in the components of plasmin-treated IgG from the known components of papain-treated IgG (Fab and Fc fragments and untreated IgG) on the physicochemical and the immunological properties and the biological activities. Incubation of IgG with 30 cu/g of plasmin for 96 hours at 20 degrees C was found to be optimum. The plasmin-treated IgG by this condition, which gives complement-fixing ability (C'H50) below 23, did not show blood pressure depression, i.e. below 10% for dogs. Three components (Pl-Fab, Pl-Fc and Pl-IgG) were isolated from the plasmin-treated IgG by gel filtration on Sephadex G200 and CM-cellulose column chromatography. The Pl-Fc and the Fc isolated from the papain-treated IgG were obtained in crystalline forms. The extinction coefficients at 280 nm were 14.0 (IgG), 14.2 (Pl-Fab) and 14.1 (Pl-Fc). The molecular weights were 163,000, 58,000 and 54,000 and the S20,w values were 6.82, 3.82 and 3.77 for Pl-IgG, Pl-Fab and Pl-Fc, respectively. These three components were identical with IgG, Fab and Fc, respectively, on the electrophoretic and the immunological demonstrations. The titer of complement-fixation of IgG was decreased from 49 to 19 by plasmin treatment, however, it was retained at low level even in each isolated component. Whe 7S IgG was incubated at 37 degrees C, reaggregation was observed, as generally understood accompanying by elevated complement-fixing ability. Whereas it was noticed after long-term incubation of plasmin-treated IgG that the changes of complement-fixing ability could occur independently from the amount of aggregates. This fact was clearly revealed on the experiments in which IgG was treated at pH 3 in glycine buffer solution.
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PMID:[Studies on the properties of the component of plasmin-treated IgG and the relation between IgG aggregates and complement-fixing ability (author's transl)]. 428 70

The uptake of 14C-glu by rat renal brushborder membrane vesicles was assayed in the presence of transmembrane ionic gradients for the purpose of characterizing surface properties which influence the transport process. Preincubation of membranes with the cationic protein lysozyme led to a significant decrease in transport activity. Similar results were obtained with polylysine and lysine. Polycations such as lysozyme and polylysine were capable of aggregating membrane vesicles whereas lysine was ineffective. Neither aggregation nor membrane injury provided an explanation for the depression of 14C-glu transport. The cationic drug harmaline at a concentration of 2.5 mM significantly reduced sodium dependent 14C-glu uptake provided drug and membranes were pre-equilibrated prior to the transport assay. Using an indirect spectrophotometric method to estimate harmaline concentrations, no evidence was obtained for strong harmaline binding to the membrane. The effect of harmaline could be eliminated by washing membranes in drug-free buffer or diluting membranes in larger volumes of sodium chloride. Membranes pretreated with the lectin Concanavalin A or the enzyme neuraminidase transported glu at control rates, but the proteolytic enzyme papain markedly impaired the transport function without altering mean vesicle volume. The optimal temperature for the assay was 30 degrees C. No temperature discontinuities in the Arrhenius plot of glu transport rates were found between 5 and 30 degrees C. These results with glutamic acid differ from data reported by other investigators on the transport characteristics of glucose and neutral amino acids by brushborder membrane vesicles. The results enhance the possibility that dicarboxylic acid binding proteins may be present on the luminal surface of proximal tubular epithelium.
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PMID:Surface properties of kidney brushborder membranes affecting the transport of glutamic acid. 612 41

A blood group A1 patient on renal dialysis developed transient low-titre, high-avidity anti-A autoantibodies and concurrently a gross depression of the A antigen. The antibodies were clearly anti-A and had no association with I, i or N antigens. They reacted in saline, papain and antiglobulin systems but were inactivated by albumin. Their pathogenesis is obscure.
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PMID:Anti-A autoantibodies with unusual properties in a patient on renal dialysis. 739 63


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