Cycle sequencing using degenerate primers containing inosines

A modified protocol for cycle sequencing DNA amplified by polymerase chain reaction (PCR) is described. The method involves two sequential linear PCR amplifications using a small amount of double-stranded DNA as a template and a stringent annealing temperature: 1) alpha-35S-dATP labeling of specific primers initially in degenerate primer mixture and 2) dideoxy-ribonucleotide termination of the extended and alpha-35S-dATP-labeled specific primers. The method does not require end labeling and is useful in sequencing PCR-amplified DNA sequences from highly degenerate primers when the sequences of the regions flanking those to be primed are unknown.

Successful experimental heart transplantation without immunosuppressive drugs

Donor-specific unresponsiveness is an important goal of heart transplantation research. Work by other investigators has shown that intrathymic transplantation of pancreatic islet cells not only leads to factor permanent acceptance of the intrathymic graft but tolerance to subsequent extrathymic islet cell transplants. We applied this concept to a model of heart allotransplantation in the rat. Recipient Lewis rats were treated with 1 ml of antilymphocyte serum and 5 x 10(7) Lewis-Brown Norway spleen cells injected into the thymus under direct vision. Twenty-one days later, heterotopic heart transplantation was performed with Lewis-Brown Norway (allograft) and Wistar-Furth (third-party allograft) donors. Control Lewis recipients received no treatment, antilymphocyte serum alone, or antilymphocyte serum plus intrathymic syngeneic Lewis spleen cells. Another group of animals received intravenous Lewis-Brown Norway cells before transplantation with Lewis-Brown Norway heart donors. Untreated control animals had heart graft survival of 6 to 10 days (mean, 7.6 days) and 7 to 9 days (mean, 7.8 days) for Lewis-Brown Norway (n = 5) and Wistar-Furth (n = 5) donors, respectively. Antilymphocyte serum alone (n = 10) failed to prolong survival of Lewis-Brown Norway grafts (mean, 10.7 days; p = not significant). Antilymphocyte serum plus intrathymic Lewis cells (n = 5) did not prolong survival of a subsequent Lewis-Brown Norway graft (mean, 9.2 days; p = not significant). Survival of Wistar-Furth third-party allografts (n = 10) was not prolonged by intrathymic Lewis-Brown Norway cells (mean survival, 13.9 days; p = not significant).(ABSTRACT TRUNCATED AT 250 WORDS)

[Studies on percutaneous absorption of ruyi jinhuang san patcher with radioisotope tracer]

Berberine is one of the active ingredients in Ruyi Jinhuang San Patcher. With 3H-berberine as the tracer, a radio-labelled method was used for determining percutaneous rate and drug concentration of berberine in plasma in vivo and in vitro. A study on the percutaneous rate of different technological plasters and various animal skins was also carried out.

Prediction of single and multivessel coronary disease in patients after myocardial infarction according to quantitative ultrasound wall-motion analysis

Regional changes in left ventricular size and function characterize left ventricular remodeling and start very early after myocardial infarction. We studied the diagnostic value of left ventricular dyssynergic patterns in predicting the presence of single versus multivessel disease (MVD). Fifty-three consecutive patients with acute myocardial infarction were studied by ECG, two-dimensional echocardiography, and angiography during the same hospitalization. Thirty-eight normal subjects served as the control group. According to the angiographic findings, the patients were categorized as having: single-vessel disease (SVD, n = 17), two-vessel disease (n = 17), and three-vessel disease (n = 19). Two-dimensional echocardiography was performed and optimal frames from five cardiac cycles were digitized and quantitatively analyzed off-line with a microcomputer. Echocardiographic wall-motion analysis demonstrated a depressed regional segmental thickening in the infarcted area that was characteristic for each echocardiographic view. In the segments remote from the infarcted area, however, the three patient groups displayed differences in function that ranged from hyperkinetic in patients with SVD to hypokinetic in patients with MVD. Patients with SVD constantly displayed a wider range of segmental thickening when compared with patients with MVD and the control group (p < 0.05). In conclusion, patients with SVD after myocardial infarction display compensatory hyperkinesis of remote segments, which is attenuated in patients with MVD. The present study introduces new parameters of segmental myocardial function that might be helpful in predicting SVD and MVD in patients after myocardial infarction.

Purification and characterization of fatty acyl-acyl carrier protein synthetase from Vibrio harveyi

A Vibrio harveyi enzyme which catalyzes the ATP-dependent ligation of fatty acids to acyl carrier protein (ACP) has been purified 6,000-fold to apparent homogeneity by anion-exchange, gel filtration, and ACP-Sepharose affinity chromatography. Purified acyl-ACP synthetase migrated as a single 62-kDa band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis and as an 80-kDa protein by gel filtration under reducing conditions. Activity of the purified enzyme was lost within hours in the absence of glycerol and low concentrations of Triton X-100. Acyl-ACP synthetase exhibited Kms for myristic acid, ACP, and ATP of 7 microM, 18 microM, and 0.3 mM, respectively. The enzyme was specific for adenine-containing nucleotides, and AMP was the product of the reaction. No covalent acyl-enzyme intermediate was observed. Enzyme activity was stimulated up to 50% by iodoacetamide but inhibited > 80% by N-ethylmaleimide: inhibition by the latter was prevented by ATP and ACP but not myristic acid. Dithiothreitol and sulfhydryl-directed reagents also influenced enzyme size, activity, and elution pattern on anion-exchange resins. The function of acyl-ACP synthetase has not been established, but it may be related to the capacity of V. harveyi to elongate exogenous fatty acids by an ACP-dependent mechanism.

Evaluation of 90:10 poly(D,L-lactide-co-glycolide) microspheres containing norethisterone: drug release and biodegradation

Poly(D,L-lactide-co-glycolide) (PLG, 90:10) microspheres containing 20% norethisterone (NET) were prepared by solvent evaporation method. Microspheres in the size ranges of 65 to 100 microns were sterilized by irradiation and used for further study. In vitro release showed fairly constant release of NET from the above microspheres over more than 90 days. However, in vivo drug release determined by residual NET analysis after i.m. injection in rats indicated a faster release rate. About 95% of NET was released in a period of 45 days. At the dose of 80 mg of microspheres, vaginal estrus cycles were inhibited for 45 days compared to 27 days for the same dose of NET crystals in rats. Biodegradation of the microspheres was tested by direct measurement of molecular weight losses and SEM observation of morphological changes of the microspheres, which showed continuous erosion in the internal matrix of microspheres with the decrease of molecular weight of PLG until total collapse of microspheres, and biodegradation was faster in rats than in human serum at 37 degrees C in vitro. Total degradation of 90:10 PLG microspheres was less than 7 months in rats and more than 9 months in vitro.

Automated detection and quantification of venous beading using Fourier analysis

Venous beading associated with diabetic retinopathy is currently assessed by means of subjective comparison to standard photographs from the modified Airlie House classification scheme. We describe a computerized grading scheme for venous beading. The algorithm, based on Fourier analysis of vessel width measurements, generates a venous beading index (VBI) for digitized colour fundus photographs. Colour photographs of local vessel segments about 1200 microns in length were evaluated by experienced graders. A comparison between the VBI and subjective grading showed good agreement. The mean VBI values across the four levels of clinical grading were significantly different (p = 0.000). Multiple comparison testing indicated that the VBI was able to significantly differentiate between all four categories except the "questionable" (grade 1) category (p < 0.05). We also found that progression of venous beading can be followed with the VBI. The results indicate that further development of automated grading of venous beading is warranted.

A novel neuropeptide, pituitary adenylate cyclase-activating polypeptide (PACAP), in human intestine: evidence for reduced content in Hirschsprung's disease

A novel neuropeptide, pituitary adenylate cyclase-activating polypeptide (PACAP), exhibits sequence homology with vasoactive intestinal polypeptide (VIP) and occurs in the mammalian brain, lung and gut. The distribution of PACAP in ganglionic and aganglionic portions of the large intestine of patients with Hirschsprung's disease was examined by immunohistochemistry and radioimmunoassay. PACAP-immunoreactive nerve fibers were distributed in all layers of the ganglionic and aganglionic segments of the intestine, although they were less numerous in the latter, and PACAP-immunoreactive nerve cell bodies were seen in the ganglionic portion of the intestine. The concentration of immunoreactive PACAP was lower in the aganglionic than in the ganglionic segment of the intestinal wall. PACAP and VIP were found to coexist in both ganglionic and aganglionic segments of the intestine. Apparently, PACAP participates in the regulation of gut motility. The scarcer PACAP innervation of the aganglionic segment may contribute to the defect in intestinal relaxation seen in patients with Hirschsprung's disease.

The cadC gene product of alkaliphilic Bacillus firmus OF4 partially restores Na+ resistance to an Escherichia coli strain lacking an Na+/H+ antiporter (NhaA)

A 5.6-kb fragment of alkaliphilic Bacillus firmus OF4 DNA was isolated by screening a library of total genomic DNA constructed in pGEM3Zf(+) for clones that reversed the Na+ sensitivity of Escherichia coli NM81, in which the gene encoding an Na+/H+ antiporter (NhaA) is deleted (E. Padan, N. Maisler, D. Taglicht, R. Karpel, and S. Schuldiner, J. Biol. Chem. 264:20297-20302, 1989). The plasmid, designated pJB22, contained two genes that apparently encode transposition functions and two genes that are apparent homologs of the cadA and cadC genes of cadmium resistance-conferring plasmid pI258 of Staphylococcus aureus. E. coli NM81 transformed with pJB22 had enhanced membrane Na+/H+ antiporter activity that was cold labile and that decreased very rapidly following isolation of everted vesicles. Subclones of pJB22 containing cadC as the only intact gene showed identical complementation patterns in vivo and in vitro. The cadC gene product of S. aureus has been proposed to act as an accessory protein for the Cd2+ efflux ATPase (CadA) (K. P. Yoon and S. Silver, J. Bacteriol. 173:7636-7642, 1991); perhaps the alkaliphile CadC also binds Na+ and enhances antiporter activity by delivering a substrate to an integral membrane antiporter. A 6.0-kb fragment overlapping the pJB22 insert was isolated to complete the sequence of the cadA homolog. A partial sequence of a region approximately 2 kb downstream of the cadA locus shares sequence similarity with plasmids from several gram-positive bacteria. These results suggest that the region of alkaliphile DNA containing the cadCA locus is present on a transposon that could reside on a heretofore-undetected endogenous plasmid.

Regulation of transcription of the cell division gene ftsA during sporulation of Bacillus subtilis

Three distinct 5' ends of ftsA mRNA were identified by S1 mapping and by primer extension analysis. These are thought to represent three transcription start sites. The transcripts from the downstream and upstream sites were detected throughout growth. The transcript from the middle site was not detected during exponential growth but was detected within 30 min of the start of sporulation, when it was the predominant transcript. Insertion of a cat cassette in the middle promoter, ftsAp2 (p2), did not affect vegetative growth but prevented postexponential symmetrical division and spore formation. Transcription from p2 was dependent on RNA polymerase containing sigma H, and promoter p2 resembled the consensus sigma H promoter. Transcription from p2 did not require expression of the spo0A, spo0B, spo0E, spo0F, or spo0K loci. Northern (RNA) blot analysis indicated that ftsA is cotranscribed with the adjacent ftsZ gene. Multiple promoters provide a mechanism by which essential vegetative genes can be subjected to sporulation control independent of control during vegetative growth. In the case of ftsA,Z, the promoters provide a mechanism to permit septum formation in conditions of nutrient depletion that might be expected to shut down the vegetative division machinery.

Preparation of fatty-acylated derivatives of acyl carrier protein using Vibrio harveyi acyl-ACP synthetase

A simple two-step purification of Vibrio harveyi fatty acyl-acyl carrier protein (acyl-ACP) synthetase, which is useful for the quantitative preparation and analysis of fatty-acylated derivatives of ACP, is described. Acyl-ACP synthetase can be partially purified from extracts of this bioluminescent bacterium by Cibacron blue chromatography and Sephacryl S-300 gel filtration and is stable for months at -20 degrees C in the presence of glycerol. Incubation of ACP from Escherichia coli with ATP and radiolabeled fatty acids (6 to 16 carbons in length) in the presence of the enzyme resulted in quantitative conversion to biologically active acylated derivatives. The enzyme reaction can be monitored by a filter disk assay to quantitate levels of ACP or by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and fluorography to detect ACP in cell extracts. With its broad fatty acid chain length specificity and optimal activity in mild nondenaturing buffers, the soluble V. harveyi acyl-ACP synthetase provides an attractive alternative to current chemical and enzymatic methods of acyl-ACP preparation and analysis.

The use of an external tibial fixator in the treatment of genu varum

This paper reports 72 cases of genu varum treated by a U-shaped osteotomy of the tibia and an oblique osteotomy of the fibula in combination with immobilization effected by a specially designed external tibial fixator. Owing to this modified approach, the patients were able to stand up and move about much earlier than usual. Our trial yielded 80.7% excellent, 16.6% good and 2.7% fair results. The treatment course was shortened to two thirds of the time required when using previously described techniques.

[Effects of caffeine on shuttle, operating behaviors, and brain metabolism in rats]

Effects of caffeine (30, 60, and 120 mg.kg-1, ip) on shuttling and operating behaviors in 80 rats were studied. Effects of caffeine (60, 120 mg.kg-1, ip) on contents of dinucleotides and pterins in 6 brain areas of 18 rats were investigated by HPLC with fluorescent detector. The results showed that the dose of caffeine that induced augment of shuttle behavior was lower than that induced operating behavior. Caffeine 120 mg.kg-1 inhibited both shuttling and operating behavior, decreased FAD content in caudate nucleus; caffeine 60 mg.kg-1 increased FAD in cerebellum and brain stem. Caffeine 60, 120 mg.kg-1 increased brain NADH contents, decreased pterin contents, and increased biopterin contents in some brain areas.

Effects of PGE2 and a thromboxane A2 analogue on uptake of IgG complexes and LDL by mesangial cells

Vasoactive agents such as angiotensin (ANG) and eicosanoids can influence macromolecular deposition in the glomerular mesangium. We studied whether prostaglandin E2 (PGE2) and U-46619 (a stable analogue of thromboxane A2) could directly affect the uptake of immunoglobulin G (IgG) complexes or low-density lipoprotein (LDL) by cultured rat mesangial cells (MC). Preincubation of MC with PGE2 (10(-6) M) resulted in decreased uptake (in counts.min-1.well-1) of IgG complexes (PGE2, 2,589 +/- 72; control, 3,840 +/- 114; P less than 0.001) and LDL particles (PGE2, 23,176 +/- 1,145; control, 37,216 +/- 4,520; P less than 0.05). MC preincubated with forskolin (10(-5) M) also showed decreased uptake of IgG complexes (forskolin, 2,896 +/- 196; control, 3,840 +/- 114; P less than 0.005) and LDL particles (forskolin, 23,176 +/- 1,145; control, 37,216 +/- 4,520; P less than 0.05). In contrast, preincubation with ANG II (5 x 10(-7) M) showed significantly higher uptake of IgG complexes (ANG II, 4,475 +/- 282; control, 3,787 +/- 277; P less than 0.05) and LDL (ANG II, 48,573 +/- 1,079; control, 44,697 +/- 770; P less than 0.05). Similarly, preincubation with U-46619 (10(-6) M) resulted in significantly higher uptake of IgG complexes (U-46619, 5,370 +/- 300; control, 3,659 +/- 307; P less than 0.02) and LDL (U-46619, 48,298 +/- 1,418; control, 44,697 +/- 770; P less than 0.05). After preincubation with cyclooxygenase inhibitor meclofenamate (10(-6) M), ANG II (5 x 10(-7) M) resulted in a significantly higher uptake of IgG complexes compared with uptake by MC treated with ANG II alone (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Lowering of serum cholesterol in hypercholesterolemic humans by tocotrienols (palmvitee)

A double-blind, crossover, 8-wk study was conducted to compare effects of the tocotrienol-enriched fraction of palm oil (200 mg palmvitee capsules/day) with those of 300 mg corn oil/d on serum lipids of hypercholesterolemic human subjects (serum cholesterol 6.21-8.02 mmol/L). Concentrations of serum total cholesterol (-15%), LDL cholesterol (-8%), Apo B (-10%), thromboxane (-25%), platelet factor 4 (-16%), and glucose (-12%) decreased significantly only in the 15 subjects given palmvitee during the initial 4 wk. The crossover confirmed these actions of palmvitee. There was a carry over effect of palmvitee. Serum cholesterol concentrations of seven hypercholesterolemic subjects (greater than 7.84 mmol/L) decreased 31% during a 4-wk period in which they were given 200 mg gamma-tocotrienol/d. This indicates that gamma-tocotrienol may be the most potent cholesterol inhibitor in palmvitee capsules. The results of this pilot study are very encouraging.

Effects of amobarbital on pterins and dinucleotides contents in rat brain

The effects of amobarbital (50 mg.kg-1 ip) on the brain concentrations of biopterin, pterin, reduced nicotinamide adenine dinucleotide (NADH) and flavin adenine dinucleotide (FAD) were studied by a reverse phase high performance liquid chromatography with fluorescent detector. Amobarbital increased FAD concentrations in 5 brain areas and pterin concentration in the cortex, but decreased biopterin concentrations in the cortex and hippocampus.

Two-way shuttlebox avoidance conditioning and brain NADH in rats

The effects of amphetamine (1.5 mg/kg) and caffeine (120 mg/kg, 75 mg/kg) on shuttle behavior and on the concentrations of reduced nicotinamide adenine dinucleotide (NADH) of the brain were studied in 56 rats from the perspective of regional brain metabolism. Amphetamine potentiated the shuttle behavior including avoidance responses and response speed, while it increased NADH concentrations in the hippocampus. The low dose of caffeine increased avoidance responses. The high dose of caffeine inhibited avoidance responses, but it had no effect on NADH concentrations in discrete brain regions.