Decreased erythrocyte nicotinamide adenine dinucleotide redox potential and abnormal pyridine nucleotide content in sickle cell disease

RBCs from individuals with sickle cell disease are more susceptible to oxidant damage. Because key antioxidant defense reactions are linked to the pyridine nucleotides nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP), we tested the hypothesis that the RBC redox potential as manifested by the NADH/[NAD+ + NADH] and NADPH/[NADP+ + NADPH] ratios is decreased in sickle erythrocytes. Our data demonstrate that sickle RBCs have a significant decrease in the NADH/[NAD+ + NADH] ratio compared with normal RBCs (P less than .00005). Interestingly, sickle RBCs also had a significant increase in total NAD content compared with normal RBCs (P less than .00005). In contrast, although sickle RBCs had a significant increase in the total NADP content compared with normal RBCs (P less than .00005), sickle RBCs had no significant alteration in the NADPH/[NADP+ + NADPH] ratio. High reticulocyte controls demonstrated that these changes were not related to cell age. Thus, sickle RBCs have a decrease in NAD redox potential that may be a reflection of their increased oxidant sensitivity. The changes in these pyridine nucleotides may have further metabolic consequences for the sickle erythrocyte.

Spectrophotometric determination of oxidized and reduced pyridine nucleotides in erythrocytes using a single extraction procedure

Several methods are available for the extraction and quantitation of oxidized and reduced pyridine nucleotides in erythrocytes. Enzymatic methods, however, are complicated by the presence of hemoglobin, which causes oxidation of NADH and NADPH during extraction. Although hemoglobin-mediated oxidation can be prevented by the addition of reducing agents, these interfere with spectrophotometric cycling assays for these nucleotides. Therefore, we have developed a method for determining oxidized and reduced NAD and NADP in human erythrocytes using a single extract. Our extraction method eliminates the need for reducing agents and thus allows the use of a spectrophotometric cycling assay. Using this method, we obtained full recovery of all added nucleotides with both normal and reticulocyte-enriched red blood cells. Our method is suitable for the determination of NAD+, NADH, NADP+, and NADPH in normal human erythrocytes and in red cells from patients with hemolytic anemia with a higher proportion of reticulocytes.

Clonidine induced variations of plasma norepinephrine and blood pressure in essential hypertension

To assess the contribution of sympathetic outflow to blood pressure in patients with essential hypertension, clonidine induced variations of plasma norepinephrine, mean arterial pressure and the pulse rate three hours after a 300 μg dose of oral clonidine, an antihypertensive agent that decreases central sympathetic outflow, were studied.

Baseline and clonidine suppressed plasma norepinephrine levels were not significantly different between the normal controls and patients with essential hypertension. The average plasma norepinephrine level, mean arterial pressure and pulse rate were significantly decreased from the baseline value in both normal control and essential hypertension (p<.005). The depressor response to sympathetic inhibition after clonidine were exaggerated in significant proportion in patients with essential hypertension compared to normal control group.

Our study suggests that the pressor sensitivity to norepinephrine plays more important role than sympathetic overactivity in some patients with essential hypertension.

Functional gamma chain-associated T cell receptors on cerebrospinal fluid-derived natural killer-like T cell clones

We have derived 33 independent T cell clones from the cerebrospinal fluid (CSF) of a patient with subacute sclerosing panencephalitis using a single T cell cloning method. 6% (2 of 33) of these clones express the T cell receptor gamma (TCR-gamma) protein and are called CSF TCR-gamma clones. Phenotypic analyses of the CSF TCR-gamma clones indicate that they are WT-31-, CD3+, CD4-, and CD8-. The TCR-gamma protein exists on the cell surface as part of an 85-kD disulphide-linked dimer noncovalently associated with the CD3 polypeptides. The CSF TCR-gamma clones have NK-like activity that can be inhibited by anti-CD3 mAbs. Both CSF TCR-gamma clones proliferated in response to anti-CD3 mAbs coupled to Sepharose beads and/or IL-2. Furthermore, stimulation of one of these clones with anti-CD3 mAbs results in a rapid rise in intracellular calcium. These data suggest that T cells bearing the CD3-TCR-gamma protein complex are functional and play a role in the human immune response.

Base sequence-specific interactions of operator DNA fragments with the lambda-cro repressor coupled with changes in their conformations

The mechanism of interaction of the operator DNA with the lambda-cro repressor protein was investigated using proton n.m.r. and photo CIDNP. Three kinds of DNA duplexes, the lambda-OR3 17-mer, phi80-OR2 19-mer and CRP binding site 22-mer, were prepared, and all of their imino proton resonances of the complexes with lambda-cro were assigned to individual base pairs. By monitoring the assigned signals of the DNA fragments and lambda-cro, it was found that in the complex of lambda-cro with lambda-OR3, two subunits of the cro dimer bind to the right and left halves of the OR3, respectively, and the bidentate binding induces a structural distortion in the middle of the 17-mer. lambda-cro itself also undergoes a conformational change including loosening of the dimeric form. In the complex of lambda-cro with phi 80-OR2, which has a 6-bp sequence common to that of lambda-OR3, one subunit of the cro dimer seems to bind specifically to the common part. However, there is only a slight conformational change in the cro dimer. In the mixture of the CRP binding site 22-mer and lambda-cro, soft contact without any conformational change was observed between them.

Secretion of proliferin

Proliferin (PLF) is a member of the PRL-GH family whose mRNA has been detected in proliferating mouse cells in culture and in mouse placenta. Suspensions of murine placental tissue have been shown to produce PLF detectable by immunoprecipitation. Here we report that PLF is secreted as a heterogeneous glycoprotein by growing mouse cell lines and placental tissue and that the first 29 amino acids of the preprotein serve as a signal peptide. Placental PLF is immunologically distinguishable from the 2 previously described mouse placental lactogens.

Diverticular disease of the colon in Korea

This study is designed to determine the relative prevalence and characteristics of diverticular disease of the colon in Korea. We did a retrospective evaluation of 16,964 consecutive barium enemas performed at Koryo General Hospital between January 1971 and October 1986, and found 100 patients with diverticular disease of the colon. The results are as follows: 1) Colonic diverticula were found in 100 patients, and incidence of 0.59% in 16,964 consecutive barium enemas. The male to female ratio was 2.1:1. 2) Incidence rose with advancing age from 0.45% in the second decade to 2.5% in the seventh decade. 3) Patient age ranged from 19 to 77 years with more than 70% of the patients in the 5th, 6th and 7th decades. 4) The greater majority (81%) of the diverticular disease the right colon. 5) Fifty percent of the cases were classified as multiple diverticula. 6) The mean age of patients with right sided diverticula was 47.5 years and that of patients with left sided diverticula was 57.7 years. The mean age of single diverticular patients was 50.4 years and that of multiple diverticular patients was 48.4 year. 7) Associated diseases were hemorrhoids (18%), gall stones (12%) and previous appendectomy (11%). Among the 29 patients who had hemorrhoids and or a previous appendectomy, 28 of those had right sided diverticula.

Multiple myeloma in Korea--clinical analysis and treatment results in 61 cases

A clinical analysis was made of 61 cases of multiple myeloma diagnosed between January 1976 and June 1984 at Seoul National University Hospital using the criteria of the Southwest Oncology Group.

The following observations were made. 1) The major clinical problems at Initial presentation were bone pain(52%), anemia(20 %), renal impairment(11%), and infection(10%). 2) Clinical stages at presentation were stage I, 11%; stage II, 8%; and stage III, 81% of patients. Three(5%) of the patients in stage II and 18(31%) in stage III showed renal impairment with a serum creatinine ≥2.0 mg/dl. 3) Combination chemotherapy produced a response rate of 29% with melphalan and prednisone, and 40% with M2 protocol(among 14 and 20 evaluable patients respectively). Both regimens showed statistically significant survival difference between responders and non-responders(p <0.01). 4) The median survival of all patients was 13 months. 5)Age, calcium level, creatinine level, and performance status were important prognostic factors on survival.

Plasma apolipoproteins and lipids in normal persons and patients with hypertension

We measured apolipoprotein A (ApoA), apolipoprotein B (ApoB), and lipid levels in 115 hypertensive patients and 100 normal subjects in order to evaluate the risk of atherosclerotic heart disease in hypertensive patients. The hypertensive patients were divided into the following subgroups: blood pressure controlled (A) and uncontrolled hypertensive subgroup (B), and without complication (C) and with complication (D).

In the hypertensive group, the mean plasma ApoA, ApoB, total cholesterol, triglyceride and beta-lipoprotein (LpB) levels were significantly higher than in the normal control group. The plasma high density lipoprotein cholesterol (HDL-cholesterol) level was not significantly different between the hypertensive group and the normal control group. ApoB/A ratio in the hypertensive group was higher than in the normal control group, but the difference was not significant statistically.

In the hypertensive subgroups, plasma Apo A was higher in all the hypertensive subgroups compared to normal control group, but these differences were not statistically significant. In subgroup B, C and D, the plasma ApoB level increased significantly as compared to the normal control group, but not so in the subgroup A. All of the subgroups had significantly higher levels of triglyceride and LpB level than the normal control group. HLD cholesteol level of all of the subgroups did not show any significant difference as compared to the normal control group. In subgroup B, C and D, the ApoB/A ratio was not significantly different from the normal control group. In the subgroup A, ApoB/A ratio was lower than in the normal control group, this was not significant statistically. Between subgroup A and B, and subgroup C and D, all of the plasma lipids and apolipoproteins did not show significant differences.

Thus our results showed that ApoB, LpB and triglyceride, which are closely related to atherosclerotic heart disease, were significantly increased in any of hypertensive subgroups compared to the normal control group.

Dynamic behavior of the imino protons of the gamma OR3 17mer in H2O solution studied by high-resolution NMR

The imino proton resonances of gamma OR3 17mer in water were observed at 500 MHz with the time-shared Redfield pulse train. All of the 17 imino proton resonances could be assigned specifically to individual base pairs by utilizing the trace of NOE connectivities between the imino and adenine C2H protons and between imino protons themselves. AT1 and 17 showed abnormally high chemical shifts in comparison with the other AT pairs. On raising the temperature, broadening of the signal occurred in a sequential manner from the terminals except for AT10 and AT11, which were broadened at a lower temperature than GC12. The relaxation rates of the imino protons were measured by the inversion recovery method. The rates at higher temperatures represent the exchange rates of the imino protons. From the temperature dependences, activation energies of about 15 kcal/mol for the AT imino protons and 23-26 kcal/mol for the GC imino protons were obtained.

Safety of outpatient cardiac catheterizations

Since 1979 most of the cardiac catheterizations at the investigators' institution have been performed as outpatient procedures. All cardiac catheterizations performed over a 66-month period were analyzed. A total of 3,071 outpatient cardiac catheterizations (83% of all cardiac catheterizations) were performed. The percutaneous femoral technique was used in 98% of the procedures. Most patients (79%) had both right and left-sided cardiac catheterization and coronary angiography, which showed significant coronary artery disease (70.4%). Only 13.6% of the study results were normal. Thirty-four patients (1.1%) had major complications, including 4 deaths (0.13%). Seventy patients (2.3%) were admitted for observation only. More than 96% of all patients did not have a major complication and were discharged the same day. Thus, outpatient cardiac catheterization can be performed safely, with a potential reduction in hospital costs and better utilization of medical beds.

Exposed tyrosine residues of lambda cro repressor protein evidenced by nitration and photo CIDNP experiments

The tyrosine residues of lambda cro repressor were partially nitrated with tetranitromethane under mild conditions. After digestion by Achromobacter protease I, the extent of nitration was determined by HPLC and amino acid analysis. Tyr 26 was most easily nitrated and Tyr 51 followed it. Tyr 10 was resistant to nitration. By comparison of the proton magnetic resonance spectrum of the partially nitrated cro protein with the above result, the aromatic proton resonances of the tyrosine side chains could be assigned to individual tyrosine residues. The extent of nitration is parallel to the accessibility to a flavin dye as measured by photo CIDNP (chemically induced dynamic nuclear polarization).

Identification of proliferin mRNA and protein in mouse placenta

Proliferin is a recently described, prolactin-related protein whose mRNA appears in several murine cell lines during active growth. We have surveyed a number of mouse organs or tissues for the presence of mRNAs that hybridize to cloned proliferin cDNA. Of the tissues tested, only the placenta yielded proliferin-related mRNA. This placental RNA is about 1 kilobase in length, increases sharply between days 8 and 10 of pregnancy, and then gradually declines through day 18. It is more abundant in RNA extracted from the fetal, compared to the maternal, part of the placenta. From a cDNA plasmid library prepared from poly(A)+ placental RNA, two types of proliferin-related clones were isolated, differing in intensity of hybridization to proliferin cDNA. By nucleotide sequence analysis, a strongly hybridizing clone was found to be nearly identical to the proliferin cDNA clone isolated from a library prepared from mRNA of a growing mouse fibroblastic cell line. Using an antiserum prepared against a synthetic proliferin fusion protein, we show that proliferin is secreted as a glycoprotein by minced placental tissue and that it differs from mouse placental lactogen. We conclude that proliferin is a placental hormone that is synthesized in certain mouse cell lines during active growth. Its function during pregnancy and during the growth of cultured cells is presently unknown.

Photo CIDNP study on the complex formation of lambda cro protein with OR3

A photo CIDNP spectrum of lambda cro repressor protein showed that one of the three tyrosines and His 35 are quite accessible to the photosensitive dye. For the remaining two tyrosine residues one is slightly accessible, but the other is inaccessible. In comparison with the result of differential nitration at tyrosine side chains followed by the peptide analysis, it can be concluded that Tyr 26 is mostly exposed and Tyr 51 is slightly exposed on the surface of the cro dimer. On the addition of OR3 17mer, His 35 and Tyr 26 are no longer accessible to the dye, which indicates that they are involved in interaction. However, a similar phenomenon was observed by adding CAP binding site 22mer. The interaction mechanism will be discussed.

Abolition of the negative endocochlear potential as a consequence of the gentamicin-furosemide interaction

The DC endocochlear potential and the AC cochlear potential in response to a 4 kHz tone were recorded in pigmented guinea pigs before and during ototoxic damage induced by sequential administration of the aminoglycoside antibiotic, gentamicin, and the loop diuretic, furosemide. Within 4 h significant diminution of the amplitude of the AC cochlear potential was accompanied by an almost complete abolition of the negative diffusion potential revealed by either furosemide administration or terminal anoxia. Thus, one of the effects of this interaction appears to involve a reduction in the potassium permeability of the cochlear partitions.