The effect of supercoiling on the in vitro transcription of the spoIIA operon from Bacillus subtilis

The spoIIA operon codes for an alternative sigma factor which appears in the early stages of a sigma factor expression cascade during sporulation in Bacillus subtilis. We have used a single round in vitro transcription assay to probe requirements for transcription initiation at the spoIIA promoter. Core RNA polymerase or holoenzyme containing sigma A was reconstituted with sigma H protein and used to transcribe the spoIIA promoter. Formation of heparin resistant transcription initiation complexes required that the spoIIA template be supercoiled. Topoisomers of the spoIIA template were created and transcribed at various temperatures. Changes in the superhelicity of template DNA had a significant influence on the amount of transcription complexes formed at the spoIIA promoter.

Endovesical instillation of mitomycin-C in preventing recurrence of superficial bladder carcinoma

It is now clear that MMC can be used as endovesical instillation after TUR, partial cystectomy or transurethral laser treatment and at the same time it has chemo-resection and chemoprophylactic efficacy. The success of treatment seems out of question on dosage but with the continuation of the instillation program. Recently, we have adopted 20 mg per instillation once every week for 40 times in the first year and once for 2-4 weeks for the second year, the overall recurrent rate was 17%. Such dosage used is more better than 2 mg, 10 mg or even 40 mg with acceptable side effects.

Systemic lupus erythematosus and pheochromocytoma

A 40-year-old Chinese woman with systemic lupus erythematosus (SLE) developed labile blood pressure 3 years after her onset of high blood pressure. Pheochromocytoma was subsequently found and removed. Postoperatively her hypertension improved without change in her SLE activity. Our case demonstrates pheochromocytoma can be a cause of hypertension in SLE.

Cloning and developmental expression of the alpha 3 chain of chicken type IX collagen

Fibrous and nonfibrous collagens comprise two major groups within the collagen family and both groups are found in a diverse variety of tissue fabrics. Type IX collagen is in the nonfibrous group; three different subunits of type IX collagen have been identified and the alpha 1 and alpha 2 subunits have been cloned. Using molecular cloning methods we have isolated, from an embryonic chicken cartilage library, cDNA clones which code for the entire alpha 3 chain of chicken type IX collagen. The cDNA clones encompass 2416 base pairs which have a conceptual open reading frame for a protein containing 675 amino acids including 193 Gly-X-Y repeats. These collagen repeats are in three separate domains which are interspersed with four major noncollagen domains. The collagen repeats also have four minor interruptions. This chain organization directly aligns with both the alpha 1 and alpha 2 chains of chicken type IX collagen. Comparison of the deduced amino acid sequence with peptide sequences of type IX collagens shows identity with 95 of the 96 known residues of the chicken alpha 3 chain and 81 of the 98 known residues of the bovine alpha 3 chain. The identical residues match those in five peptide fragments, two from the bovine protein and three from the chicken protein. The chicken and bovine alpha 3 chains have conserved cross-linking sites, separated by 137 residues which span 40 nm, the length of the hole zone in a collagen fibril. The NC3 domain of the chicken alpha 3 chain contains a repeat Cys-Pro motif which is present in both vertebrate and invertebrate nonfibrillar collagens. Northern blot hybridization exhibits a major mRNA of about 3.3 kilobases; this transcript is found in cartilaginous tissues in the embryo, including the developing limb and is not detected in other tissues or in the precondensation stage of limb development. The composite data delineate the primary structure of the alpha 3 chain of chicken type IX collagen, show its close relationship to the alpha 1 and alpha 2 chains, demonstrate its mRNA transcript, and show the appearance of that transcript in tissues of the developing chick embryo.

Loss of hippocampal acetylcholinesterase staining after fornix lesion in the monkey

Cholinergic denervation of the hippocampal formation has been extensively studied in rodents but not in primates. Therefore we studied the changes in acetylcholinesterase histochemical staining of the hippocampus occurring after bilateral transection of the fornices in the cynomolgus monkey. Animals were sacrificed 1.5, 6, 13, and 23 weeks after surgery. We found a 40-50% reduction in the density of acetylcholinesterase-positive fibers in the four analyzed regions (dentate gyrus, CA3, CA1, and subiculum) 1.5 week after surgery and a 60-80% reduction at longer time intervals. The characteristic diffuse AChE staining found in hippocampi from control animals disappeared after fornix lesion, except in the inner third of the molecular layer of the dentate gyrus. We did not find any evidence of spontaneous cholinergic reinnervation over the 6-month period. Thus, as in rats, fornix lesion produces dramatic changes in hippocampal AChE staining, presumably caused by a massive cholinergic denervation. However, in contrast to rodents, spontaneous reinnervation does not seem to occur in the months following the lesion in primates.

Abnormal patterns of DNA methylation in human neoplasia: potential consequences for tumor progression

An imbalance of DNA methylation, involving widespread hypomethylation, regional hypermethylation and increased cellular capacity for methylation, is characteristic of human neoplasia. This imbalance begins in preneoplastic cells and becomes more extensive throughout subsequent stages of tumor progression. In normal cells, a primary function of DNA methylation may be to modulate compartmentalization of DNA to ensure that regional areas of transcriptionally active chromatin replicate earlier than the bulk transcriptionally inactive chromatin. We argue here that the altered methylation patterns observed during tumor progression, especially regional hypermethylation, may mark--or even help to establish--abnormalities of chromatin organization. In turn, these changes in chromatin structure may, through direct transcriptional inactivation of genes, predisposition to mutations, and allelic deletions, mediate the progressive losses of gene expression associated with tumor development.

Control of the initiation of sporulation in Bacillus subtilis by a phosphorelay

Sporulation in Bacillus subtilis is a developmental process induced as a response to nutritional stress. Activation of sporulation-specific gene transcription is under the control of the spoOA gene product. The SpoOA protein and the SpoOF protein are both homologous to response regulator proteins of two-component regulatory systems which control bacterial responses to a variety of environmental challenges. Response regulators are activated by specific kinases which phosphorylate them. In this study, it was shown that phosphorylation of SpoOA occurs via a phosphotransferase which is the product of the spoOB locus. The phosphodonor in this reaction is the phosphorylated form of SpoOF. It is postulated that SpoOF acts as a secondary messenger that can be phosphorylated by a variety of kinases depending on the particular environmental stress. The series of phosphate transfer reactions in this system is called a phosphorelay. The end product of this series of reactions is SpoOA approximately P which is shown to have greater affinity for the DNA target, the OA box, of SpoOA on the abrB promoter than the unphosphorylated form. SpoOA approximately P, but not SpoOA, was shown to be an activator of transcription of the spoIIA operon which codes for the sporulation-specific sigma factor sigma F. Thus, the initiation of sporulation is dependent on SpoOA approximately P which arises through the phosphorelay and which acts as a transcription factor to repress certain genes, e.g. abrB, and activate others, e.g. spoIIA.

Evaluation of anorectal malformations using magnetic resonance imaging

Demonstration of the anatomy of the anal sphincter muscles in patients with anorectal malformations is important. The information can help us in preoperative planning for surgical repair and in predicting a patient's prognosis. For patients with postoperative incontinence, the anatomic imaging is especially useful. Magnetic resonance imaging (MRI) is a relatively new diagnostic tool that generates images of sections of the body taken in any plane. From Oct. 1989 to Dec. 1990, twelve patients received MRI examination, imaging the pelvis and lumbosacral spine in the sagittal, transverse, and coronal planes. Normal anorectum in 2 cases was recorded for comparison. The other ten cases included three of postoperative incontinence, three of cloacal anomaly, and four of questionable level of anorectal anomaly before MRI evaluation. Our experience proved that MRI is a useful examination in selected patients with anorectal malformation. To be cost-effective, we suggest that MRI is performed only in patients with postoperative incontinence and some questionable cases.

Stress fracture of the diaphysis of the ulna

Stress fracture of the diaphysis of the ulna is rare and only 6 cases were found in a literature review. We present a further case occurring in a weightlifter.

Opioid receptor binding properties of analgesic analogues of cholecystokinin octapeptide

Four analogues of cholecystokinin (CCK) octapeptide having analgesic activity after i.c.v. administration and high affinity for CCK-B receptors were studied for their ability to displace specific ligands, [3H]D-Phe-Cys-Tyr-D-Trp-Orn-Thr-Pen-Thr-NH2. [3H][D-Pen2, 4'-Cl-Phe4,D-Pen5]enkephalin and [3H]U-69,593, for mu-, delta- and kappa-opioid receptors, respectively. None of the analogues tested have high affinity for either mu- or kappa-receptors (IC50 values greater than 0.7 microM), but their IC50 values for delta-receptors range from 29 to 1023 nM. The results suggest a relationship between the ligand requirements of CCK-B and delta-opioid receptors which further implies a possible structural relationship between these receptors.

Functional size analysis of pyrophosphatase from Rhodospirillum rubrum determined by radiation inactivation

A radiation inactivation technique was employed to determine the functional size of pyrophosphatase (PPase) from the chromatophores of Rhodospirillum rubrum. The activities of hydrolysis and synthesis reactions of pyrophosphatase and its coupled proton translocation decayed in a simple exponential function with the increase of radiation dosages. D37 values of 5.2 +/- 0.7 and 5.8 +/- 0.8 Mrads were obtained for pyrophosphate hydrolysis and its associated proton translocation yielding molecular masses of 167.7 +/- 30.7 and 156.3 +/- 26.6 kDa, respectively. Similarly, a D37 value of 4.4 +/- 0.6 Mrads was measured for the acid-base induced pyrophosphate synthesis resulting in a radiation sensitive size of 196.3 +/- 31.9 kDa.

An SfiI restriction map of the Bacillus subtilis 168 genome

A restriction map of 24 SfiI (GGCCN4/NGGCC) restriction fragments has been constructed for the Bacillus subtilis genome. The combined sizes of the fragments indicate a genome size of approx. 4.2 Mb. The SfiI fragments range in size from 7-730 kb. Genetic markers have been located on 19 of the SfiI fragments, and 69 genetic markers have been assigned to the SfiI restriction map.

Transcription of the Bacillus subtilis spoIIA locus

The spoIIA operon encodes three genes, including the structural gene for a sporulation-induced sigma factor sigma F. We used deletion analysis of spoIIA-lacZ fusions to define the location of the spoIIA promoter. We found that sigma H-RNA polymerase transcribes spoIIA accurately in vitro and propose that sigma H directs transcription of spoIIA during sporulation.

Short- and long-term results of catheter balloon percutaneous transvenous mitral commissurotomy

Percutaneous transvenous mitral commissurotomy (PTMC) was performed in 219 patients with symptomatic, severe rheumatic mitral stenosis. There were 59 men and 160 women, aged 19 to 76 years (mean 43). Pliable, noncalcified valves were present in 139 (group 1), and calcified valves or severe mitral subvalvular lesions, or both, in 80 patients (group 2). Atrial fibrillation was present in 133 patients (61%) and 1+ or 2+ mitral regurgitation in 59 (27%). Technical failure occurred with 3 patients in our early experience. There was no cardiac tamponade or emergency surgery. The only in-hospital death occurred 3 days after the procedure in a group 2 premoribund patient in whom last-resort PTMC created 3+ mitral regurgitation. Mitral regurgitation appeared or increased in 72 patients (33%); 3+ mitral regurgitation resulted in 12 patients (6%). There were 3 systemic embolisms. Atrial left-to-right shunts measured by oximetry developed in 33 patients (15%). Immediately after PTMC, there were significantly reduced (p = 0.0001) left atrial pressure (24.2 +/- 5.6 to 15.1 +/- 5.1 mm Hg), mean pulmonary artery pressure (39.7 +/- 13.0 to 30.6 +/- 10.9 mm Hg) and mitral valve gradient (13.0 +/- 5.1 to 5.7 +/- 2.6 mm Hg). Mitral valve area increased from 1.0 +/- 0.3 to 2.0 +/- 0.7 cm2 (p = 0.0001) and cardiac output from 4.4 +/- 1.4 to 4.7 +/- 1.2 liters/min (p less than 0.01). The results mirrored clinical improvements in 209 patients (97%). Multivariate analysis showed an echo score greater than 8, and valvular calcification and severe subvalvular lesions as independent predictors for suboptimal hemodynamic results.(ABSTRACT TRUNCATED AT 250 WORDS)

Mutational dissociation of the positive and negative regulatory properties of the Spo0A sporulation transcription factor of Bacillus subtilis

The Spo0A regulatory protein controls the onset of stationary phase and sporulation by controlling transcription in both a negative and a positive manner depending on the promoter affected. Missense mutations, e.g., spo0A9V, which result in alterations in the eleventh amino acid preceding the C terminus of the Spo0A protein, give rise to a protein active as a negative regulator of the abrB gene but unable to activate transcription of the spoIIA gene. Second-site suppressors of spo0A9V occurred within the spo0A gene at codons 162 and 174. These suppressors did not suppress a spo0F mutation, indicating that the suppressed protein still requires phosphorylation for activity. The results suggest that the C terminus of Spo0A interacts with the transcription complex to activate transcription.

Sites of stromelysin cleavage in collagen types II, IX, X, and XI of cartilage

Human recombinant stromelysin-1 was shown to cleave four types of collagen (types II, IX, X, and XI) prepared from bovine and rat cartilages at specific sites. Stromelysin-1 cleaved salt-soluble native molecules of type IX collagen into two main triple-helical fragments, COL1 and COL2,3. Protein microsequencing identified the exact cleavage sites in the NC2 domain of all three chains, alpha 1(IX), alpha 2(IX), and alpha 3(IX). Stromelysin-1 also acted as a "telopeptidase," in that it efficiently clipped intact molecules of types II and XI collagens at sites just inside their terminal cross-linking hydroxylysine residues. Native molecules of type X collagen were cleaved by stromelysin-1 within their triple helical domains at a COOH-terminal site that reduced the alpha 1(X) chain size by 10 kDa. These findings suggest an important role for stromelysin in the turnover and remodeling of the collagenous matrix of cartilage both normally and in degenerative joint disease.

The cartilage collagens: structural and metabolic studies

The molecular sites of crosslinking between types II and IX collagens of bovine articular cartilage have been defined. All 3 chains of the type IX molecule, alpha 1 (IX), alpha 2 (IX) and alpha 3 (IX), contain an hydroxylysine close to the N-terminus of the central COL2 triple helical domain that can crosslink to an hydroxylysine aldehyde in an alpha 1 (II) N-telopeptide. One chain, alpha 3 (IX), also contains a triple helical hydroxylysine farther into COL2 that crosslinks specifically to an alpha 1 (II)C-telopeptide. The metalloprotease, stromelysin, is capable of depolymerizing the type II-type IX complex by bisecting the type IX collagen molecule and cleaving telopeptides from type II collagen. We discuss the significance of these findings in understanding the structure, growth and remodeling of the heterotypic collagen network of articular cartilage.

Gait analysis after total knee replacement for degenerative arthritis

Using quantitative gait analysis and clinical evaluation, the functional results of 18 total knee replacement (TKR) in 13 patients who had osteoarthritis were evaluated. Nine knees each were replaced by Insall-Burnstein (I/B) posterior stabilized design or Miller-Galante (M/G) prosthesis. The former was fixed by cement and needed to sacrifice posterior cruciate ligament (PCL), while the latter was inserted without cement, and PCL could be reserved. The follow-up period ranged from 21 to 77 months. At the final follow-up, the overall functional knee score was 94.1 points (I/B 95.0 versus M/G 92.2). The average active knee flexion was 109.7 degrees (I/B 116.4 degrees versus M/G 102.9). For gait analysis, three cameras synchronized with 2 AMTI force plates were connected to the VICON system to provide kinetic and kinematic data during level walking. The data were compared with the non-operated side; and with younger subjects as normal control. They were supposed to possess normal knee functions. In patients after knee prosthesis, they tended to have slower velocity, shorter step length and less cadence. They also showed shorter swing and longer stance phases. In the M/G knee ground, the duration for double-limb support was longer, but shorter for single-limb support. The angles of knee flexion-extension of both prosthetic groups became narrower. Their ground reaction forces in both vertical and medio-lateral directions were larger than in the control groups, probably due to quadriceps dysfunction and subtle imbalance of the soft tissue-prosthesis complex around the joint.(ABSTRACT TRUNCATED AT 250 WORDS)

Origins of the afferent fibers to the cat superior cervical ganglion

The origins of the afferent fibers to the cat's superior cervical ganglion (SCG) were demonstrated by using the retrograde horseradish peroxidase tracing method. We found that the preganglionic neurons were located in the spinal segments C8-T5, particularly in T1-T3. These neurons were situated mainly in the intermediolateral column. The extra-SCG neurons along with the cervical sympathetic trunk originated ipsilaterally from the middle cervical and stellate ganglia, and contralaterally from the caudal part of the SCG. Labeled neurons also originated from the mandibular division of the trigeminal ganglion. Our results demonstrated that many fiber sources projected to the SCG, which plays a complicated synaptic role in controlling the visceral organs of the head and neck region.

Modification of human placental alkaline phosphatase by periodate-oxidized 1,N6-ethenoadenosine monophosphate

Oxidation of 1,N6-ethenoadenosine monophosphate (epsilon AMP) with periodate cleaved the cis-diol of the ribose ring and resulted in the formation of a dialdehyde derivative (epsilon AMP-dial). At room temperature epsilon AMP-dial was unstable and underwent beta-elimination to give 4',5'-anhydro-1,N6-ethenoadenosine dialdehyde acetal (A epsilon Ado-dial). These nucleotide analogues were found to inactivate human placental alkaline phosphatase in a time- and concentration-dependent manner. epsilon AMP-dial was shown to be an affinity label for the enzyme on the basis of the following criteria. (a) Kinetics of the enzyme activity loss over a wide range of epsilon AMP-dial concentration showed a saturating phenomenon. Removal of the phosphate group made the reagent (A epsilon Ado-dial) become a general chemical modifying reagent. (b) The artificial substrate p-nitrophenyl phosphate gave substantial protection of the enzyme against inactivation. (c) epsilon AMP-dial was a substrate and a partial mixed-type inhibitor for the enzyme. Results of the inhibition and protection studies indicated that the reagent and substrate could combine with the enzyme simultaneously. Besides the phosphate-binding domain, an induced hydrophobic region is proposed for the substrate-binding site for human placental alkaline phosphatase.

Long-term hemodynamic results of percutaneous transvenous mitral commissurotomy in rheumatic mitral stenosis with pliable, non-calcified valves

Percutaneous transvenous mitral commissurotomy (PTMC) for severe, symptomatic mitral stenosis was successfully performed in 47 of 50 patients with pliable, non-calcified valves. The procedure resulted in immediate hemodynamic and sustained clinical improvements in all patients. Repeat cardiac catheterization was performed in 22 patients at a mean follow-up period of 15 months (range 12 to 29). The patients were similar to the other 25 patients in regard to gender, age, clinical and hemodynamic characteristics. There were 4 males and 18 females with a mean age of 37 years (range 20 to 61). Immediately after PTMC, there were significant increases in the mitral valve area (1.0 +/- 0.2 to 2.4 +/- .9cm2, p less than 0.001) and cardiac index (3.1 +/- 0.7 to 3.3 +/- 0.7 l/min/m2, p less than 0.05) and significant (p less than 0.001) decreases in the left atrial pressure (25.7 +/- 6.4 to 13.2 +/- 3.9 mmHg), the mitral valve gradient (15.7 +/- 5.7 to 3.9 +/- 1.4 mmHg), mean pulmonary arterial pressure (41.5 +/- 10.7 to 29.2 +/- 10.9 mmHg) and the pulmonary vascular resistance (4.2 +/ 3.4 to 3.5 +/- 2.9 Wood unit). At follow-up study, the mitral valve area (2.2 +/- 0.7 cm2) and the left atrial pressure (12.6 +/- 3.7 mmHg) remained unchanged. There were further decreases in the mean pulmonary arterial pressure (22.4 +/- 5.9 mmHg, p less than 0.05) and the pulmonary vascular resistance (2.0 +/- 1.5 Wood unit, p less than 0.05). There were significant (p less than 0.05) increases in the mitral valve gradient (6.6 +/- 2.5 mmHg) and the cardiac output (3.6 +/- 0.7 l/min/m2).(ABSTRACT TRUNCATED AT 250 WORDS)

Catecholaminergic innervation of the hippocampus in the cynomolgus monkey

We studied the immunocytochemical distribution of catecholaminergic fibers in the hippocampal formation from two cynomolgus monkeys by using phenylethanolamine-N-methyltransferase, dopamine-beta-hydroxylase, and tyrosine-hydroxylase antibodies. There were no phenylethanolamine-N-methyltransferase immunoreactive fibers suggesting the lack of epinephrine containing fibers. In order to compare the distributions of tyrosine-hydroxylase and dopamine-beta-hydroxylase immunoreactive fibers, we counted fibers in four hippocampal regions, the dentate gyrus, CA3, CA1, and the subiculum at three different rostrocaudal levels. The distributions of dopamine-beta-hydroxylase and tyrosine-hydroxylase immunoreactive fibers were overlapping but clearly different, suggesting that the hippocampus receives both noradrenergic and dopaminergic inputs in primates. Dopamine-beta-hydroxylase-immunoreactive fibers were present in moderate density and roughly evenly distributed throughout the hippocampus. Tyrosine-hydroxylase immunoreactive fibers were found in high density in the dentate gyrus, in the stratum lacunosum-moleculare, and in the molecular layer of the subiculum. There were only minor side-side and rostrocaudal differences in the distribution of tyrosine-hydroxylase and dopamine-beta-hydroxylase immunoreactive fibers. The identification of a putative dopaminergic projection to primate hippocampus, which is more dense and widely distributed than in the rodent, parallels similar increases in dopaminergic projections reported for primate cerebral neocortex.

[Surgical treatment of esophageal atresia--6 years of experience]

Surgical treatment of fourteen infants with esophageal atresia over the past six years was reviewed retrospectively. Two patients had esophageal atresia without tracheoesophageal fistula (Gross Type A), the other 12 patients had distal tracheoesophageal fistula (Gross Type C). Associated anomalies were found in three patients: one had a patent ductus arterious, another had trisomy 18, and the third had polydactylia. According to Waterston's risk group classification, there were 7 cases in Group A, 5 in Group B and 2 in Group C. The choice of operative method mainly depended on the distance between the two esophageal ends. Two patients with Type A atresia were treated by a staged operation because the distance between the two esophageal blind ends far exceeds 2 cm. A Type C patient with a "gap" longer than 2 cm who first had his esophagostomy, gastrostomy and ligation of the tracheoesophageal fistula at another hospital was transferred to us to get an esophageal reconstruction using a right-side ileocolon. Another ten Type C patients with a "gap" of less than 2 cm were operated on by extrapleural end-to-end esophago-esophagostomy after their tracheo-esophageal fistula was closed. The remaining Type C patient with a longer gap of about 3 cm was treated by primary anastomosis following mobilization of the upper pouch as well as limited mobilization of the lower esophageal segment. Anastomotic leakage was found in three patients. One patient developed subsequent stricture when the leakage was healed. The causes of mortality in three patients were pulmonary hemorrhage, sepsis and pneumonia respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

500-MHz proton NMR evidence for two solution structures of the common arm base-paired segment of wheat germ 5S ribosomal RNA

The base-pair protons of the common arm duplex fragment of wheat germ (Triticum aestivum) ribosomal 5S RNA have been identified and assigned by means of 500-MHz proton NMR spectroscopy. The two previously reported extra base pairs within the fragment [Li et al. (1987) Biochemistry 26, 1578-1585] are now explained by the presence of two distinct solution structures of the common arm fragment (and its corresponding base-paired segment in intact 5S rRNA). The present conclusions are supported by one- and two-dimensional proton homonuclear Overhauser enhancements in H2O and by temperature variation and Mg2+ titration of the downfield 1H NMR spectrum. The difference between the two conformers is most likely due to difference in helical tightness. Some additional amino proton resonances have also been assigned.