Callus of Pinus roxburghii (Chir pine) and its cytology

Callus was initiated form different vegetative parts of 3 to 5-week-old seedlings of Pinus roxburghii Sargent. Best results were obtained on Murashige and Skoog's revised medium supplemented with 4 mg1⁻¹ NAA or 2,4-D, 1 mg1⁻¹ kinetin and 15% coconut milk. Callus was grown successfully for more than a year without deterioration in its growth. Growth rate studies on the calli form cytoledon explants were undertaken with different concentrations of auxins and cytokinins. Histogenic differentiation of tracheids ocurred in all the calli, with the formation of bordered pits preceding the reticulate thickenings of the tracherary walls. Cells in the 4 to 12-week-old calli were predominantly diploid, though a few polyploid and aneuploid cells were also noticed. Chromosome bridges and laggards were observed in a number of cells.     

Optical and electron paramagnetic resonance spectroscopic studies on purine hydroxylase II from Aspergillus nidulans

Purine hydroxylase II from Aspergillus nidulans contains a molybdenum cofactor very similar to that found in a number of other molybdenum-containing hydroxylases. (A. nidulans contains two purine hydroxylases, I and II, related to each other by possession of a common cofactor and overlapping substrate specificity.) Addition of reducing substrates effects bleaching of the visible absorption spectrum of the enzyme, the decrease in absorbance at 450 nm being linearly proportional to that at 550 nm. No increase in absorption at longer wavelengths was observed during such titrations. Electron paramagnetic resonance studies of reduced samples of native and modified enzyme species showed the presence of a number of Mo(V) signals (gav = 1.97), exhibiting H hyperfine coupling, comparable to those in the corresponding enzymes from other sources. The enzyme possesses two non-heme-iron-sulfur centers, one (Fe2S2)I with gav less than 2.0 and the other (Fe2S2)II with gav greater than 2.0. The flavin radical signal observed at pH 7.8 had a linewidth of 1.5 mT, indicating it to be the anionic form FAD- . In this respect purine hydroxylase II is unique among all molybdenum-containing hydroxylases studied to date.     

Lepromin-induced suppressor cells in patients with leprosy.

The possibility of an active mechanism of immunologic suppression in leprosy was explored by assessing the in vitro lymphocyte responses of 61 leprosy patients and 30 normal individuals to the mitogen Con A in the presence or absence of Dharmendra lepromin. Lepromin-induced suppression of Con A stimulation was found in 32 of 35 lepromatous patients and 15 of 15 borderline patients, but only 2 of 15 tuberculoid patients and 2 of 30 normal controls. Cell fractionation studies indicated at least two cell populations involved in the in vitro lepromin-induced suppressor activity, adherent cells and T gamma-cells.     

Rapid purification of a restriction endonuclease from Escherichia coli RY13

Summary A two step method for the purification of restriction endonuclease Eco RI was developed. The first step involved the purification of the enzyme on Cibacron Blue-F3GA-agarose column, followed by a hydroxyapatite column. The enzyme was homogeneous on SDS-PAGE and completely free from contaminating nucleases and phosphatases, and can be used for direct DNA hydrolysis.     

Rates of rebleeding,thrombosis and mortality associated with resumption of anticoagulant therapy after anticoagulant-related bleeding

BACKGROUND:Data on resuming oral anticoagulants (OACs) after bleeding are primarily from studies involving patients given warfarin, with few data on direct OACs (DOACs). We aimed to characterize prescribing patterns for OACs after OAC-related bleeding and compare the rates of bleeding, thrombosis and mortality in patients who resumed either type of OAC with those who did not.METHODS:We conducted a population-based cohort study of adults aged 66 years or older who were admitted to hospital for bleeding while receiving OACs from Apr. 1, 2012, to Mar. 31, 2017, using linked administrative health databases from Ontario. We used competing risk methods to calculate cause-specific adjusted hazard ratios (HRs) for thrombosis, bleeding and mortality with resumption of OACs adjusted as a time-varying covariate. We determined time to OAC resumption using the Kaplan–Meier method.RESULTS:We included 6793 patients with gastrointestinal (n = 4297, 63.3%), intracranial (n = 805, 11.9%) or other bleeding (n = 1691, 25.0%). At cohort entry, 3874 patients (57.0%) were prescribed warfarin and 2919 patients (43.0%) were prescribed a DOAC. The most common indication for OAC was atrial fibrillation (n = 5557, 81.8%), followed by venous thromboembolism (n = 1367, 20.1%). Oral anticoagulants were resumed in 4792 patients (70.5%) within 365 days of the index bleed. The median time to resumption was 46 (interquartile range 6–550) days. We found that resuming OAC was associated with reduced rates of thrombosis (adjusted HR 0.60, 95% confidence interval [CI] 0.50–0.72) and mortality (adjusted HR 0.54, 95% CI 0.48–0.60), and an increased rate of rebleeding (adjusted HR 1.88, 95% CI 1.64–2.17).INTERPRETATION:We found that resuming OAC is associated with a reduction in thrombosis and mortality but an increase in bleeding. Randomized controlled trials that evaluate the net benefit of strategies for resumption of OAC after a bleeding event are warranted.

Oral anticoagulants (OACs) are used to prevent and treat arterial and venous thrombosis. Bleeding associated with OACs is the most common adverse drug event that leads to visits to the emergency department, hospital admissions and death.^1,2 When OACs are withheld after a bleed, patients are exposed to an increased risk of thrombosis and possibly death. A challenging clinical problem is determining whether OACs should be resumed after a bleed and, if so, the optimal strategy for resumption.Oral anticoagulant therapy is stopped permanently in a substantial proportion of patients after gastrointestinal (GI) or intracranial bleeding (50% and 64%, respectively)^3,4 despite evidence that suggests a benefit to restarting.^3,5–9 Direct OACs (DOACs) are now recommended for stroke prevention in patients with atrial fibrillation (AF) and for the treatment of venous thromboembolism (VTE) based on substantial evidence.^10–12 However, resumption of OACs after bleeding has been assessed primarily in small studies of patients treated with warfarin that did not report on extracranial non-GI bleeding.^3,4,13Using population-based data, we aimed to characterize prescribing patterns for OACs and compare outcomes between patients who resumed OAC with those who did not after OAC-related bleeding. Our secondary aims were to compare outcomes separately after OAC-related GI bleeding, intracranial hemorrhage, extracranial non-GI bleeding and any bleeding.     

Accuracy of Perceived Treatment Needs Among Geriatric Denture Wearers1

Patient satisfaction with and accuracy in assessing condition of dentures and oral tissue were related to their clinical evaluation and several psychological factors in 50 denture wearers 60 years of age or older. Seventy percent of those examined wore clinically inadequate dentures and 34% had unsatisfactory oral tissue. Few respondents were dissatisfied when clinical examination revealed satisfactory conditions but 70% were satisfied with inadequate dentures and 50% with unsatisfactory oral tissue. Contrary t o expectation, accuracy was not found significantly related to clinical evaluation or to psychological factors. However, satisfaction with dentures was related to their clinical evaluation: dissatisfied respondents had technically superior dentures as compared with those satisfied. These findings suggest that psychological factors are not related to denture patient assessment of their oral condition and that dissatisfaction may be of benefit to their oral health. The high proportion of those unaware of denture inadequacies indicates the need for patient education directed toward over-, as well as under-, adapters.     

Metallothionein-I in the plasma and liver of neonatal rats.

The concentrations of metallothionein-I in the plasma and liver of neonatal rats were measured by radioimmunoassay. Plasma concentrations of the protein in male and female 4-day-old rats were 350 and 740 ng/ml respectively, and declined rapidly to only 3.5 ng/ml at 32 days of age. Concentrations in liver were also high in the newborn rats (200 micrograms/g), and declined from 12 days of age onwards.     

pH and temperature optima for growth and sporulation in some common fungi from city waste

Relationships between the growth of certain fungi isolated from city waste and pH and temperature were examined by two methods. The tested isolates showed their maximum growth and sporulation at different pHs while temperature requirements were the same (28°C), except forHumicola grisea (43°C).Cladosporium herbarum andH. grisea showed double pH optima. The ranges of pH and temperature for sporulation were more limited than those for the vegetative growth. Although all the tested isolates showed wide tolerances to pH and temperature, the degree of tolerance varied with the isolates. A considerable change from the initial pH of the liquid medium was noted at the end of the experiment.