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Biomedical subjects

T Kudo

Publications and source records attributed to T Kudo.

At least 703 records · Page 39Linked to original sources
PubMed1981

Free sigma factor of Escherichia coli RNA polymerase can bind to DNA.

Free sigma factor from E. coli RNA polymerase holoenzyme was shown to associate with supercoiled pBR350 and pBRH4 plasmid DNA s by two methods. The banding pattern of sigma factor through a nondenaturing polyacrylamide slab gel was significantly altered in the presence of supercoiled DNA; sigma factor had little or no affinity to linear, double- or single-stranded DNA. At saturation, approximately one sigma factor was bound/200 base pairs of supercoiled pBR350 DNA. By the nitrocellulose filter trapping method, sigma factor was able to bind supercoiled pBRH4 DNA much more efficiently than linear double-stranded pBRH4 DNA. These results suggest that sigma factor plays a role in the binding of holoenzyme to DNA and may be involved in locally denaturing DNA in the promoter region as postulated by previous investigators.

DNA, Bacterial↗
PubMed1981

Free sigma subunit of Bacillus subtilis RNA polymerase binds to DNA.

The affinity of Bacillus subtilis RNA polymerase sigma and delta subunits to DNA was examined by a non-denaturing polyacrylamide slab gel electrophoresis method which made it possible to resolve DNA-bound and free subunits. The results revealed that sigma subunit, but not delta subunit had a relatively high affinity for double stranded DNA. The sigma subunit was bound maximally to super-coiled pGR1-3 plasmid DNA at a mass ratio of sigma/DNA of 0.7. With B. subtilis double stranded linear DNA one sigma subunit was bound per approximately 1,000 base pairs. The sigma-DNA complex was sufficiently stable for isolation by a molecular gel filtration column. The sigma subunit had much higher affinity for super-coiled than for linear pGR1-3 DNA or for linear double stranded or denatured DNA from B. subtilis, E. coli, and calf thymus. These results indicate that the free B. subtilis sigma subunit, in contrast to the E. coli sigma subunit, can bind by itself to DNA.

Bacillus subtilis↗
PubMed1981

Importance of monitoring the circulating blood volume in patients with cerebral vasospasm after subarachnoid hemorrhage.

We used the isotope dilution technique to monitor circulating blood volume (CBV) in three patients with ruptured cerebral aneurysms who developed pre- or postoperative ischemic symptoms that responded well to intravascular volume expansion therapy with blood transfusion and plasma expanders. In the first and second cases, predeterioration CBVs were obtained. Both of these patients showed hypovolemia and a decreased red blood cell volume at the time of neurological deterioration. A predeterioration CBV was not available for the third patient for comparison, but his red cell volume was also markedly decreased. Postrecovery CBVs were obtained in the second and third cases. Our data suggested that a depleted red blood cell volume was more responsible for neurological deterioration than was a lowered plasma volume. To prevent the occurrence of hypovolemia and anemia in aneurysm patients, we should monitor CBV not only at the time of neurological deterioration, but also at the time of admission and during the immediate postoperative period.

Adult↗
PubMed1981

Algesiogenic and analgesic activities of synthetic substance P.

The objective of our study was to determine whether the pure synthetic substance P(SP) is algesiogenic or analgesic when administered centrally or peripherally. The relationships between SP-induced analgesia and the content of morphine-like factor (MLF) in the brain were also studied. Intracarotid arterial administration of SP (20-200 microgram) produced no pseudoaffective responses to pain in six out of nine rats, but in the remaining three, there was an exhibition of these responses. Chlorpheniramine pretreatment antagonized these responses. On cantharidin blister base experiments in humans, SP (10(-3) g/ml) produced slight pain and an itchy sensation. SP given intracerebroventricularly produced an analgesia in mice in a dose of 5 ng/mouse, as determined by the acetic acid-induced writhing and hot plate methods. These SP-induced analgesia were antagonized by naloxone pretreatment. SP did not alter the content of MLF in the mouse whole brain. However, SP5-11 not only produced an analgesia but also increased the content of MLF. These results suggest that SP has a slight algesiogenic activity which might be mediated by histamine and a slight analgesic activity which might be mediated by MLF.

Analgesics↗