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G B Schmidt

Publications and source records attributed to G B Schmidt.

13 recordsLinked to original sources
PubMed1991

Isolation, crystallization, crystal structure analysis and refinement of constitutive C-phycocyanin from the chromatically adapting cyanobacterium Fremyella diplosiphon at 1.66 A resolution.

Constitutive phycocyanin from cyanobacterium Fremyella diplosiphon (Calothrix sp. PCC 7601) grown in green light, has been isolated and crystallized. The crystals belong to the space group R3 with cell constants a = b = 180.26 A, c = 61.24 A, alpha = beta = 90 degrees, gamma = 120 degrees. The crystal structure has been determined by Patterson search techniques using the molecular model of C-phycocyanin from the cyanobacterium Agmenellum quadruplicatum. The asymmetric unit of the crystal cell consists of two (alpha beta)-monomers related by a local dyad. Three asymmetric units are arranged around a crystallographic triad and form an (alpha beta)6-hexamer, the functional unit in the native antenna rod. The initial structure has been refined in a cyclic manner by energy-restrained crystallographic refinement and modelling until the conventional crystallographic R-factor converged at 18.1% with data to a resolution of 1.66 A. The molecular structure resembles closely the C-phycocyanins of Mastigocladus laminosus and A. quadruplicatum. The conformation and configuration of the alpha-84 and beta-84 chromophores is very similar to the corresponding chromophores in the trimeric C-phycocyanin of M. laminosus, whereas the beta-155 chromophore differs in configuration with C(4)-Z, C(10)-Z and C(15)-Z compared to C(4)-Z, C(10)-Z, C(15)-Z,E. The stereochemistry of the beta-155 chiral centres is C(2)-RC(3)-R and C(31)-S, respectively, whereas alpha-84 and beta-84 have C(2)-RC(3)-R and C(31)-R. The amino acid sequences of constitutive and inducible phycocyanin differ mainly in residues located on the surface of the beta-subunits that mediate the inter-hexameric contacts.

Amino Acid Sequence↗
PubMed1976

Continuous positive airway pressure in the prophylaxis of the adult respiratory distress syndrome.

After an operation upon the abdomen, certain patients have a high risk of developing acute respiratory failure or the adult respiratory distress syndrome. These patients at high risk have been mechanically ventilated during the postoperative period in an attempt to prevent the onset of respiratory insufficiency. As a method of prophylaxis, continuous positive airway pressure has the advantages of increasing the functional residual capacity with minimal effects on the cardiac output, low potential for barotrauma and simplicity of equipment. Alternate patients at risk following an operation on the upper part of the abdomen were placed on 8 centimeters of water continuous positive airway pressure for the first 24 hours postoperatively. Fifty-six controls and 56 patients receiving continuous positive airway pressure were studied. In ten controls, adult respiratory distress syndrome developed, and three died in respiratory failure. Only one of the group receiving continuous positive airway pressure met standard criteria for the diagnosis of adult respiratory distress syndrome. In addition, in 25 patients serving as controls, respiratory complications other than adult respiratory distress syndrome developed compared with the development in only 11 receiving continuous positive airway pressure9

Abdomen↗
PubMed1975

Continuous positive airway pressure in the prophylaxis of the adult respiratory distress syndrome (ARDS).

Alternate patients believed to be at risk for developing ARDS were placed on CPAP for the first twenty-four hours post upper abdominal surgery. Ten of the 58 controls developed ARDS, requiring prolonged mechanical ventilation with a 30% mortality rate. Only one of the 59 CPAP patients developed evidence of ARDS. This patient, however, is believed to have had fluid overload, and responded quickly to diuretics and was extubated within two days. Thus, prophylactic CPAP has greatly decreased our postoperative morbidity and mortality related to respiratory causes.

Abdomen↗
PubMed1974

Amyotonia congenita.

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Anesthesia, Intravenous↗
PubMed1971

Evidence for a magnesium pump in Bacillus cereus T.

Unlike Escherichia coli, Bacillus cereus T appears to accumulate Mg(2+) in its cell sap against a concentration gradient. Over a range of Mg(2+) in the growth medium from 5 x 10(-5) to 1.35 x 10(-2)m, the concentration of Mg(2+) in the cell sap of B. cereus T was maintained at about 6 x 10(-3)m, and ribosome-bound Mg(2+) and spermidine, as well as the spermidine concentration in the cell sap, appear to be unaffected by the concentration of Mg(2+) in the growth medium. Inhibition of growth of E. coli by streptomycin is progressively reversed by increasing the concentration of Mg(2+) in the growth medium above 5 mm. The finding that similar increases of Mg(2+) in the growth medium did not reverse the inhibition of B. cereus T is also consistent with the conclusion that B. cereus T, unlike E. coli, accumulates Mg(2+) to a constant concentration in its cell sap.

Amines↗
PubMedDate not supplied

EPAP without intubation.

The early institution of end expiratory pressure has been demonstrated frequently to be beneficial in acute respiratory failure. EPAP without intubation allows early therapy while avoiding the complications associated with the high flow rates utilized with CPAP. Three patients are described, illustrating the administration of EPAP for mild ARDS, aspiration penumonia, and postoperative atelectasis.

Adolescent↗