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In the mouse, mutations in the c-Kit proto-oncogene, a member of the receptor tyrosine kinase (RTK) gene family, have pleiotropic effects on hematopoiesis, pigmentation and fertility (dominant spotting, W). However, in the Wsh allele the defect is confined to abnormal pigmentation caused by the disruption of 5' regulatory sequences of Kit leaving an intact structural gene. In this report, the previously published physical map around the Pdgfra-Kit-Flk1 RTK loci is extended by mapping the loci encoding the GABAA (gamma-aminobutyric acid) receptor subunit beta 1, Gabrb1 and a cytoplasmic kinase (Tec) 3 Mb proximal to Kit. PFGE analysis of the wild-type (C57BL/6J) chromosome demonstrates the following gene order: cen-Gabrb1-Tec-Pdgfra-Kit, whereas the analysis of Wsh/Wsh DNA is consistent with the order: cen-Gabrb1-Pdgfra-Tec-Kit. This altered physical map can be explained by an inversion on the Wsh chromosome located proximally to the Kit locus and spanning the 2.8 Mb Pdgfra-Tec chromosomal segment. This high resolution physical mapping study identifies large DNA fragments that span the two inversion breakpoints and potentially carry Kit upstream regulatory elements involved in the control of Kit expression during embryonic development.

Guided by ichthyotoxic activity against goldfish, a new lipopeptide, malyngamide H [1], and its corresponding free acid, 7-methoxytetradec-4(E)-enoic acid [2], have been isolated from the tropical marine cyanobacterium Lyngbya majuscula. The structure of the new carbon skeleton borne by malyngamide H was elucidated on the basis of spectroscopic analysis, mainly 2D nmr. The absolute stereochemistry of the cyclohexenone moiety of malyngamide H [1] was deduced by a combination of 2D NOESY and exciton chirality circular dichroism spectroscopy.

Background: Despite conventional attitudes that interdict sphincter-preservation surgery (SPS) for cancers arising in the terminal 3 cm of rectum, we have selectively employed high-dose preoperative external radiation (HDPER) and either radical or local excisional SPS techniques for rectal cancer arising between the 0.5 and 3 cm levels above the anorectal ring. We have reported a preliminary experience with HDPER and full-thickness local excision (FTLE) and three different methods of radical SPS. We now describe our experience with a single method of radical excision, transanal abdominal transanal proctosigmoidectomy with coloanal anastomosis (TATA) and FTLE in conjunction with HDPER for cancers of the distal 3 cm of rectum based on specific guidelines., Methods: Since 1984, 109 patients with cancers at or below the 3 cm level have been treated with HDPER in doses of 4,500-7,000 cGy and a sphincter-preserving radical or local excision method in a prospective rectal cancer management program. Sixty-five patients (group A) underwent transanal abdominal transanal radical proctosigmoidectomy with colonal anastomosis (TATA) and 44 patients (group B) underwent FTLE., Results: There was one death (1%). Mean follow-up was 40 months. Local recurrence rates for groups A and B were 9 and 14%, respectively. Kaplan-Meier 5-year actuarial survival was 85 and 90% for groups A and B, respectively, and 87% collectively., Conclusion: Experience with 109 patients with cancers of the distal 3 cm of rectum indicates that SPS can be accomplished by either radical or local excisional methods with acceptable local control and survival if HDPER and strict selection guidelines are employed.

Three mutations in the mouse, white spotting (W), rump white (Rw), and patch (Ph), are described as a "gene triplet" on the basis of their close genetic linkage and similar mutant phenotypes. The finding that the W phenotype results from mutations altering the c-kit protooncogene, and that Ph is associated with the deletion of Pdgfra, suggested specific molecular reagents which could be used for the analysis of the chromosomal structure of the third mutation, rump white. Such studies indicated that Rw is associated with a large chromosomal inversion. In this study, we showed that it is possible to generate molecular markers specific for the Rw chromosome, as recombination is suppressed between the inverted portion of the Rw chromosome and the wild-type homologue. Using one such marker, we were able to genotype the offspring of Rw/+ intercrosses. This enabled us to show that Rw homozygote embryos die around 9.5 days of gestation. Histological analysis revealed that the embryos undergo gastrulation, forming three germ layers, and in some cases, exhibit a defined axial midline with an apparent notochordal plate. However, mutant embryos are significantly smaller than the wild-type, with the size difference evident from Day 7.5 and becoming more disparate as development progresses. These morphological data further support the genetic evidence indicating that the developmental lethality of the Rw mutation is not caused by the disruption of a gene within the cluster of RTKs in the central portion of mouse chromosome 5. Furthermore, we present evidence that both Kit and Pdgfra are expressed from the Rw chromosome in several adult tissues. The results of these studies suggest that the identification of the sequence(s) disrupted by the Rw mutation will provide further insight into the regulation of early postimplantation development.

We constructed a yeast artificial chromosome (YAC) contig spanning the genes encoding Kit (Kit), the platelet-derived growth factor alpha receptor (Pdgfra), and fetal liver kinase 1 (Flk1), three members of a receptor tyrosine kinase gene family located in the central portion of mouse chromosome 5. The orientation of YAC clones and the extent of their overlap was determined by "probe content mapping," that is, hybridization analysis of YAC clones using the available gene probes and YAC end sequences. For four YAC clones, which constitute a minimal set spanning 1.8 Mb, a detailed restriction map was constructed. This map, in conjunction with the previously published long-range restriction map, indicates the order, the physical distances, and the relative transcriptional orientations of the Pdgfra, Kit, and Flk1 genes. The YAC clones and corresponding YAC end probes presented here provide an important resource for the molecular analysis of a cluster of developmental mutations, namely dominant white spotting (W), patch (Ph), recessive spotting (rs), and rump-white (Rw), associated with this chromosomal region.

The arthroscope permits treatment of degenerative tears of the TFC and associated lesions. It lends itself to the assessment and treatment of both "primary" and "secondary" ulnar impaction syndromes. Ulnocarpal, radiocarpal, and midcarpal synovitis can be excised, as can partial tears of the lunatotriquetral interosseous ligament. The primum movens of the ulnar impaction syndrome, a long ulna, can be shortened arthroscopically if the positive ulnar variance is less than 4 mm and no distal radioulnar joint instability or degenerative changes are noted. Although an arthroscopic "wafer" procedure is possible, more clinical studies are needed to allow an accurate assessment of its efficacy.

We are studying the chromosomal structure of three developmental mutations, dominant spotting (W), patch (Ph), and rump white (Rw) on mouse chromosome 5. These mutations are clustered in a region containing three genes encoding tyrosine kinase receptors (Kit, Pdgfra, and Flk1). Using probes for these genes and for a closely linked locus, D5Mn125, we established a high-resolution physical map covering approximately 2.8 Mb. The entire chromosomal segment mapped in this study is deleted in the W19H mutation. The map indicates the position of the Ph deletion, which encompasses not more than 400 kb around and including the Pdgfra gene. The map also places the distal breakpoint of the Rw inversion to a limited chromosomal segment between Kit and Pdgfra. In light of the structure of the Ph-W-Rw region, we interpret the previously published complementation analyses as indicating that the pigmentation defect in Rw/+ heterozygotes could be due to the disruption of Kit and/or Pdgfra regulatory sequences, whereas the gene(s) responsible for the recessive lethality of Rw/Rw embryos is not closely linked to the Ph and W loci and maps proximally to the W19H deletion. The structural analysis of chromosomal rearrangements associated with W19H, Ph, and Rw combined with the high-resolution physical mapping points the way toward the definition of these mutations in molecular terms and isolation of homologous genes on human chromosome 4.

The results of 278 endoscopic carpal tunnel releases using the extrabursal dual portal Chow technique were analyzed prospectively. The majority of patients were pain free by the 57th postoperative day. The perioperative complication rate was 1.7%. The late complication rate was 2.8%. Two cases were converted to open carpal tunnel release. The average time to return to full-duty work was 65 days in those patients covered by worker's compensation, whereas it was 21 days in the privately insured (non-worker's compensation) patients. The endoscopic release of the transverse carpal ligament is an effective technique for the treatment of carpal tunnel syndrome with a low complications rate. Return to full employment requires more time in those patients covered by worker's compensation.

The rump-white (Rw) mutation in the mouse was previously mapped as part of a cluster of spotting genes on Chromosome (Chr) 5 that includes the dominant spotting (W) and patch (Ph) loci. Recent studies have shown that the W locus encodes the KIT tyrosine kinase cell surface receptor and that Ph is a deletional mutation encompassing the platelet-derived growth factor receptor alpha subunit (Pdgfra) gene. However, the molecular basis of the Rw mutation remains to be established. We have analyzed an interspecific Mus spretus backcross segregating Rw and several loci proximal and distal to the W/Ph/Rw region to study the basis of this mutation. These studies indicated that loci within the En2 to Kit region of the chromosome do not recombine with one another even though they have been separated in other mapping studies presented here and elsewhere. We conducted a series of fluorescent in situ hybridization (FISH) studies with genomic probes to En2, Msx1, D5Buc1, and Kit to compare the physical order of these loci on the Rw and wild-type chromosomes. The Kit locus mapped to approximately the same region on both chromosomes of the Rw heterozygotes, while the positions of En2, Msx1, and D5Buc1 were reversed on the two chromosomes. Taken together, both the genetic and physical mapping data establish that the Rw mutation is associated with an inversion involving loci in the proximal region of Chromosome 5.

Insulin-like growth factor-binding protein-1s are important modulators of the insulin-like growth factors that may have both positive and negative effects on the ability of insulin-like growth factors to stimulate cell growth. The IGFBP-1 gene is one of the most highly induced immediate-early genes after partial hepatectomy. The IGFBP-1 gene is also expressed at a high level during fetal liver development and in response to nutritional changes and diabetes. Therefore it may have important roles in liver growth and metabolism. To begin to examine the regulation of this gene, we cloned and sequenced the entire mouse IGFBP-1 gene. Its structure is highly similar to that of the human gene, and, in addition to the exonic regions, the two genes are highly conserved in specific regions in the promoter and first intron. Analysis of this conservation allows us to predict important regulatory sites that define the tissue specific and insulin-mediated regulation of the gene and identify potential sites that might be important for the transcriptional induction during liver regeneration. The mouse gene is located on mouse chromosome 11; it is found at the boundary between regions in the mouse genome homologous to human chromosomes 22 and 7. We found IGFBP-1 mRNA in both parenchymal and nonparenchymal RNA after partial hepatectomy. Using in situ hybridization of IGFBP-1 mRNA in regenerating rat liver tissue, we demonstrated IGFBP-1 transcripts in several cell types. We found that IGFBP-1 gene induction after partial hepatectomy is paralleled by protein expression.(ABSTRACT TRUNCATED AT 250 WORDS)

We isolated clones encoding the mouse high-mobility-group (Hmg) chromatin protein, Hmg1, from a 7.5-day mouse embryo cDNA library. The translated amino acid sequence encodes a protein of 24,890 daltons and is identical to previously characterized mouse, rat, and hamster Hmg1. However, comparison of the two mouse Hmg1 cDNA sequences revealed nine sequence alterations. This observation, together with the finding of a complex pattern of hybridizing bands in genomic Southern analysis, suggests that mouse Hmg1 is encoded by a multigene family. The expression of Hmg1 was examined by Northern analysis of RNA isolated from the early mouse embryo and revealed a predominant 1.5-kb transcript in conjunction with low levels of a 2.5-kb transcript. Further analysis of mouse embryos by in situ hybridization showed that Hmg1 transcripts are expressed in high abundance during early mouse embryogenesis. As development progresses, Hmg1 transcript abundance is modulated in a spatially restricted and developmentally regulated manner. Chromosomal localization with recombinant inbred strains revealed that Hmg1-related sequences are widely dispersed in the mouse genome. Here we also report the mapping of six Hmg1 loci to mouse Chromosomes (Chrs) 10, 13, 16, and 17.

A novel sphingolipid containing an iso-fatty acid, (4E,8E)-N-13'-methyltetradecanoyl-1-O-beta-D-glucopyra nosyl-4-sphingadiene, was isolated from the Oregon marine sponge Halichondria panicea and its structure determined using a combination of spectroscopic and chemical degradation techniques. A second galactosyl-ceramide, which contained an unusually long chain fatty acid amide component, was also isolated from H. panicea.

The results of 84 wrist arthroscopies in 74 patients (performed by the same surgeon) were reviewed retrospectively. Arthroscopies were categorized as "diagnostic"--to identify unknown pathology, "staging"--to assess the severity of known pathology, and "operative"--to treat known pathology. Ninety-eight percent of diagnostic arthroscopies accurately established details of the pathology in question. Ninety-six percent of staging arthroscopies helped guide future clinical management. Of the patients in the operative category, 35% improved after treatment with arthroscopy alone, requiring no further surgical intervention. This study shows that wrist arthroscopy is a powerful diagnostic and staging tool and suggests that it may also develop into a valuable treatment modality.

In the pulse-echo method using broadband transducers, flaw detection can be improved by using optimal bandpass filtering to resolve flaw echoes surrounded by grain scatterers. Optimal bandpass filtering is achieved by examining spectral information of the flaw and grain echoes where frequency differences have been experimentally shown to be predictable in the Rayleigh scattering region. Using optimal frequency band information, flaw echoes can then be discriminated by applying adaptive thresholding techniques based on surrounding range cells. The authors present order-statistic (OS) processors, ranked and trimmed mean (TM), to robustly estimate the threshold while censoring outliers. The design of these OS processors is accomplished analytically based on constant false-alarm rate (CFAR) detection. It is shown that OS-CFAR and TM-CFAR processors can detect flaw echoes robustly with the CFAR of 10 (-4) where the range cell used for the threshold estimate contains outliers.

Split-spectrum processing of broadband ultrasonic signals coupled with order statistic filtering has proven to be effective in improving the flaw-to-clutter ratio of backscattered signals. It is shown that an optimal rank can be obtained with a prior knowledge of flaw-to-clutter ratio and the underlying distributions. The order statistic filter performs well where the flaw and clutter echoes have good statistical separation in a given quantile region representing a particular rank (e.g. minimum, median, maximum). Order statistic filters are analyzed for the situation in which the observations do not contain equivalent statistical information. Experimental and simulated results are presented to show how effectively the order statistic filter can utilize information contained in different frequency bands to improve flaw detection.

The enzymes involved in the purine interconversion pathway of wild-type and purine analog-resistant strains of Methanobacterium thermoautotrophicum Marburg were assayed by radiometric and spectrophotometric methods. Wild-type cells incorporated labeled adenine, guanine, and hypoxanthine, whereas mutant strains varied in their ability to incorporate these bases. Adenine, guanine, hypoxanthine, and xanthine were activated by phosphoribosyltransferase activities present in wild-type cell extracts. Some mutant strains simultaneously lost the ability to convert both guanine and hypoxanthine to the respective nucleotide, suggesting that the same enzyme activates both bases. Adenosine, guanosine, and inosine phosphorylase activities were detected for the conversion of base to nucleoside. Adenine deaminase activity was detected at low levels. Guanine deaminase activity was not detected. Nucleoside kinase activities for the conversion of adenosine, guanosine, and inosine to the respective nucleotides were detected by a new assay. The nucleotide-interconverting enzymes AMP deaminase, succinyl-AMP synthetase, succinyl-AMP lyase, IMP dehydrogenase, and GMP synthetase were present in extracts; GMP reductase was not detected. The results indicate that this autotrophic methanogen has a complex system for the utilization of exogenous purines.

The activity of the biosurfactant produced by Bacillus licheniformis strain JF-2 was quantified using a unit defined as the amount of the acid-precipitated biosurfactant that lowered the surface tension by 10 mN/m. One unit was equivalent to 37 micrograms/ml of the acid-precipitated biosurfactant. Acid precipitation was very effective in the removal of the biosurfactant from the spent medium. Among the solvents tested methanol was the most efficient in extracting the surfactant activity from acid-precipitated material. Thin-layer chromatography of the acid-precipitated biosurfactant revealed four components, two of which contained a lipid moiety and one of which contained an amino group. The methanol-soluble fraction also contained these four components. Studies suggested that all four components were needed for full activity. The lowest interfacial tensions against octane were observed when NaC1 concentrations were 50 g/l or greater. Calcium concentrations greater than 25 g/l significantly increased the interfacial tension.

We evaluated the effects of esmolol, a short acting (t1/2 beta = 9 min) beta-blocker on hemodynamics during noxious stimulation associated with aortocoronary bypass surgery. Group E (n = 10) and P (n = 10) patients had their morning dose of beta- or calcium blockers withheld except for nifedipine, and were given infusions of esmolol (E) or placebo (P) beginning prior to anesthetic induction and continuing until mediastinal dissection. Group S (n = 10) patients received their usual medication the morning of surgery and received neither esmolol nor placebo. All patients received fentanyl infusions for anesthesia and pancuronium for relaxation. Esmolol patients had no changes in heart rate throughout the study. In contrast, significant increases in heart rate occurred during induction, intubation, and surgical stimulation in Groups P and S. Esmolol patients had a statistically significant but transient increase in pulmonary capillary wedge pressure (PCWP) after intubation, which did not require treatment. There were no significant changes in PCWP in Group S and a decrease in PCWP in Group P patients. We conclude that esmolol was effective in attenuating potentially deleterious responses to noxious stimulation during fentanyl-pancuronium anesthesia.

The site of action of the phorbol esters, potent tumor promoters, is not known. To evaluate the possible role of the nucleus in the specific interaction of phorbol esters with cells, the activity of phorbol-12-myristate-13-acetate was determined on intact and enucleated Swiss 3T3 mouse cells. The parameter which was used as a measure of cellular response was the morphological change of transient cell rounding and process formation which was induced in these cells within 2 hr by biologically active phorbol esters. We found no effect of the cell nucleus on the responsiveness of the cells to phorbol-12-myristate-13-acetate. Likewise, the responsiveness of the cells to phorbol-12,13-dibenzoate, phorbol-12,13-diacetate, and phorbol-13-acetate was nuclear independent. These three derivatives were examined because they have comparable efficacies to phorbol-12-myristate-13-acetate (i.e., similar maximal effects) in a variety of in vitro systems but vary greatly (10,000-fold) in potency. We conclude that the phorbol ester receptor coupled to the morphological response (and presumably those other cellular responses which share the same structure-activity requirements) is nonnuclear.

The sural artery and vein were used successfully as recipient vessels in nine patients who required free flap reconstruction about the knee. The anatomy of the sural vessels and the potential advantages of their use as free flap recipients are reviewed and discussed. Indications include popliteal vessels that are absent or severely damaged, as determined by preoperative angiography. No anastomotic complications were encountered in this series, indicating that the sural artery and vein can be used successfully as recipient vessels.

Fourteen patients with open non-salvageable intraarticular fractures of the proximal interphalangeal joint or metacarpophalangeal joint, underwent immediate silastic arthroplasty using Swanson H.P. hinged implants. The patients' ages ranged from 14 to 49 years, with an average of 29 years. Time from surgery to final examination ranged from 4 months to 6 years, with an average of 26 months. The active range of motion obtained at the metacarpophalangeal joint arthroplasties ranged from 45 to 80 degrees, with an average of 60 degrees. The active range of motion obtained at the proximal interphalangeal joint arthroplasties ranged from 0 to 70 degrees, with an average of 29 degrees. Better results were generally obtained at the metacarpophalangeal level, and in those arthroplasties performed in non-amputated digits. There were no post-operative infections and all but one joint were stable.

We have previously characterized specific binding of the phorbol ester tumor promoter [20-3H]phorbol 12,13-dibutyrate to several tissues, including mouse skin and brain. We report here that specific binding activity in chicken brain increases dramatically during development. In whole embryonic chicken brain, binding increased from 2.0 to 6.8 to 10.6 pmol/mg of protein at 7, 14, and 20 days, respectively. Adult chicken brain bound 15 pmol/mg of protein. In contrast to specific binding activity, binding affinity remained constant. Substantial regional localization of binding activity within the brain was found. For calf brain, representative values ranged from 4.6 pmol/mg for medulla to 38.1 pmol/mg for frontal lobe. Binding affinity did not vary. Inhibition of binding by postulated neurotransmitters and antagonists was examined. D-Propranolol and quinidine, membrane-stabilizing drugs, inhibited binding competitively, although at mM concentrations.

Often the existence of reverberations in the ultrasonic pulse-echo imaging of multilayered structure prevents the direct characterization of each layer. The reverberating pattern is governed by the integrity of the layers, and deterioration of these layers can generate complex and unpredictable patterns. Analytical models for the classification of reverberant patterns using both normal and unique angle scanning schemes are presented. The theoretical model has been utilized in the experimental studies of a particular multilayered reverberant environment that exists in the detection of corrosion and/or volatile changes in stem generator tubing used in nuclear power plants. Various reverberant patterns can be recognized that are in close agreement with theoretical predictions.

Fentanyl in doses of 50-60 microgram/kg has been reported to produce anesthesia with remarkable hemodynamic stability in patients with coronary artery disease (CAD). Because the authors had observed hypertension and tachycardia in response to noxious stimulation during aortocoronary bypass (ACB) operations in patients so anesthetized, they studied the hemodynamic changes and anesthetic conditions produced by fentanyl/O2/relaxant anesthesia in patients undergoing elective ACB. Twelve patients with left ventricular (LV) ejection fractions greater than 0.4 were maintained on propranolol until 10 hours before operation and were premedicated with fentanyl, diazepam, and scopolamine. Cannulae were inserted before the study commenced for measurement of intravascular pressures, arterial blood gases, and thermodilution cardiac output. The patients breathed 100 per cent oxygen throughout the study. Controlled ventilation aided by succinylcholine to reduce truncal rigidity maintained PaCO2 at 30-45 torr. Measurements were made after each of the following: breathing oxygen (control), 10 microgram/kg fentanyl, 50 microgram/kg fentanyl, and 0.1 mg/kg pancuronium, tracheal intubation, skin incision, and sternotomy. Fentanyl alone produced no significant hemodynamic changes. Fentanyl and pancuronium in combination produced increased heart rate and reduced stroke volume. Significant and progressively greater increases in mean arterial pressure and systemic vascular resistance followed intubation, skin incision, and sternotomy. Chest rigidity occurred in every patient at a lower fentanyl dose than did unresponsiveness. While fentanyl, 62.4 +/- 2.9 microgram/kg (SE), produced minor hemodynamic changes, it failed to block hemodynamic responses to noxious stimulation. Such changes resulted in increased cardiac work, and could have affected myocardial oxygen balance unfavorably. In eight of the 12 patients, following the last set of measurements, supplementary anesthetic agents were required to maintain hemodynamic stability during the surgical procedure. The authors suggest that this fentanyl/O2/relaxant technique should be modified for patients with severe CAD and reasonably good LV function.

This study provides evidence that the preoptic region and the substantia nigra interact in the control of maternal behavior. In the first experiment, large electrolytic lesions of the substantia nigra were found to severely disrupt maternal behavior and cause stereotyped motor activity in postpartum lactating rats. In order to test the hypothesis that the preoptic region and the substantia nigra interact in the control of maternal behavior, a second experiment employed an asymmetrical lesion design. Postpartum lactating rats that received a unilateral knife cut severing the lateral connections of the medial preoptic area and a contralateral lesion of the substantia nigra showed larger deficits in maternal behavior than either sham females or females that received a unilateral preoptic knife cut paired with an ipsilateral substantia nigra lesion. Measurements of body weights, body temperatures, and stereotyped behavior indicated that the differences in maternal behavior between the ipsilateral and contralateral groups could not be explained on the basis of nonspecific effects.

The receptors for the phorbol ester tumor promoters are present in highest concentration in the brain. We have examined the distribution of receptors in mouse brain by light microscopic autoradiography. Marked differences in receptor levels were found both between brain regions and between layers of a single region. Binding was high in hippocampus, cerebral cortex, striatum and substantia nigra, lower in thalamus and pons. In cerebellum, binding was high in the stratum moleculare, intermediate in the stratum granulosum and low in the lamina alba. The localization suggests a functional role for the receptors within brain, and it permits comparison with other known activities. For example, the pattern of localization is distinct from those reported for neurotransmitter receptors or for phospholipids.

In vivo phosphorus nuclear magnetic resonance spectroscopy of muscle was performed at rest, during work and during postexercise recovery in rats injected with iodo-acetate (IA) (35-40 mg.kg-1, intra-arterially), in order to follow bio-energetic changes in muscle with acute glycolytic block. Three animals with contracture had very low ratios of phosphocreatine:inorganic phosphate (PCr:Pi) at rest (0.5-0.9). The PCr:Pi were normal at rest (6.9 +/- 2.0, +/- 2 SD) in all other rats. Exercise-induced continuous accumulation of phosphomonoesters (PME), the characteristic finding of glycolytic block, was observed. The end-exercise levels of PME correlated with the degree of block measured in vitro. During steady-state work, induced by nerve stimulation at four frequencies, PCr:Pi values were significantly lower (p less than 0.02) than the control values at 0.25, 1.0 and 2.0 Hz. The ATP levels fell during exercise to reach 75% +/- 7% of initial values. The recovery of PCr:Pi from exercise and the disappearance of PME were slow. Two animals which survived the IA injection demonstrated much lower PME accumulation 18 h later. It is concluded that in acute muscle glycolytic block: (1) energy metabolism is impaired during exercise and also at rest, (2) accumulating PME can serve as an indicator of the degree of glycolytic block, (3) ATP levels fall during work, and (4) postexercise recovery is slow. The findings are compared with 31P-NMR observations in chronic muscle glycolytic disorders.

This study examined a simple technique for reducing contamination during catheterization of the internal jugular vein. Sixty patients were assigned randomly to receive either a traditional iodophor skin cleansing or an alcohol cleansing, followed by application of an iodophor-impregnated sterile film. In the cleansed with iodophor alone group, 83% of the anesthesiologists' glove tips were contaminated, and 13% of the catheter tips were contaminated. In contrast, in the group in which the sterile film was employed, contamination of gloves and catheters was virtually eliminated.

Eighty-six patients admitted with evolving myocardial infarction within 6 hours of symptom onset were treated with streptokinase. Thirty-nine received intracoronary streptokinase, and 47 received intravenous streptokinase. There were no streptokinase-related complications. Twenty-three patients treated with intracoronary streptokinase and 28 patients receiving intravenous streptokinase underwent coronary artery bypass grafting. On admission, 16 patients receiving intracoronary streptokinase had electrocardiographic evidence of anterolateral evolving myocardial infarction and seven had evidence of inferior evolving myocardial infarction. Time from first symptom to intracoronary streptokinase was 4.4 +/- 1.6 hours. In seven patients, intracoronary streptokinase failed to open the obstructed coronary. All developed severe left ventricular hypokinesia in the area supplied by that coronary artery. In spite of recanalization, nine of 14 patients developed severe hypokinesia in the supplied area, and one an apical aneurysm. Four patients developed mild to moderate hypokinesia, and one had no left ventricular damage. On admission, 14 patients receiving intravenous streptokinase had electrocardiographic evidence of anterolateral evolving myocardial infarction and four had evidence of inferior evolving myocardial infarction. Time from first symptom to intravenous streptokinase was 3.2 +/- 1.5 hours. In seven patients, intravenous streptokinase failed to open the coronary, and all developed severe hypokinesia of the supplied area, with formation of apical left ventricular aneurysm in three. In 21 patients, intravenous streptokinase opened the artery. Eighteen angiographies performed 9.6 +/- 7.9 days after therapy showed a normal left ventricle in eight patients, moderate hypokinesia in seven, and severe hypokinesia in three. Time from first symptom to therapy was shorter in the patients receiving intravenous therapy (p less than 0.01). Coronary artery bypass grafting and four resections after left ventricular aneurysm were performed without operative death. Two patients receiving intracoronary therapy died in the hospital, and one died 2 months later from arrhythmias. Freedom from angina and rehabilitation (New York Heart Association Class I) were achieved in 69.5% of patients receiving intracoronary streptokinase and in 75% of patients receiving intravenous streptokinase. Thus streptokinase-induced thrombolysis salvages myocardium, and the intravenous route seems as effective as the intracoronary. Advantages of the former are earlier administration that might increase myocardial salvage, no invasive procedure, and lesser cost.

Free flap versatility and dependability make the final result of microvascular reconstruction highly predictable. Free tissue transplantation should be considered as a primary treatment after trauma. The early use of free tissue transfer will result in fewer operations and a shortened duration of hospitalization in the initial post-trauma period.

The anatomic distribution and potential arterial flow patterns of the circumflex scapular artery were investigated by Microfil injection. These studies demonstrated that the circumflex scapular artery lies within the dorsal thoracic fascia, which plays a significant role in the circulation of the overlying skin and subcutaneous tissue. We conclude that scapular/parascapular flaps are fasciocutaneous flaps, the dorsal thoracic fascia can be transferred as a free flap without its overlying skin and subcutaneous tissue, and intercommunication exists between the myocutaneous perforators of the latissimus dorsi myocutaneous flap and the vascular plexus of the dorsal thoracic fascia. We present microvascular cases in which the vascular properties of the dorsal thoracic fascia facilitated wound closure with free fascia flaps or expanded cutaneous or myocutaneous flaps.

The methyl carbon of ribothymidine in Loop IV of the tRNA of Streptococcus faecalis, Bacillus subtilis, and some other microorganisms is derived directly from 5,10-methylenetetrahydrofolate, not S-adenosylmethionine. The pure enzyme from S. faecalis also requires FADH2. We have obtained evidence that tetrahydrofolate is a product of the reaction and demonstrated that label from [5-3H]5-deazaFMNH2 is incorporated into the methyl moiety of ribothymidine. These data indicate that the enzyme uses methylenetetrahydrofolate solely as a 1-carbon donor and employs FADH2 as a reducing agent in vitro according to the following reaction: tRNA(U psi C) + CH2 = THF + FADH2 leads to tRNA(T psi C) + THF + FAD.

Among a variety of deep muscle trigger points, the piriform muscle trigger point is selected for individual scrutiny. This seems fully justified by the great potential for confusing this entity with discogenic disease and consequently having unnecessary surgical procedures carried out.The diagnosis can be made from findings on simple physical diagnostic tests and an appropriate history. Low back and hip pain with pain radiating down the back of the leg should suggest piriform syndrome as part of the differential diagnosis. This is especially true if a female patient has complaint of dyspareunia. Pain and weakness on resisted abduction-external rotation of the thigh is a sign of piriform syndrome. This is confirmed by tenderness and reproduction of the patient's complaints by digital pressure over the belly of the piriform muscle, completing the diagnostic criteria. Local injection of the muscle belly is curative. There are no laboratory or x-ray findings leading to a diagnosis.

Patients who had undergone aorto-coronary bypass grafts (ACBG) were assessed for the incidence of cardiac complications in the postoperative period following subsequent non-cardiac surgery. One hundred and twenty-one patients had 13 complications (11 per cent). A significantly higher risk of cardiac complications (27 per cent) was found in patients undergoing non-cardiac procedures in the first month after ACBG. This remained higher (17 per cent) until the sixth month following ACBG. Significant factors which increased the risk of cardiac complications in the postoperative period included preoperative congestive heart failure (33 per cent), cardiac risk index score classification of III or IV (37 per cent), surgery on major vessels, and surgery necessitated because of a complication of the ACBG itself (17 per cent). No correlation was found between cardiac complication rates and recurrent angina, hypertension, the use of beta-blockers or digoxin, or anaesthetic technique. It is suggested that all but emergency surgery should be postponed in the first month following ACBG, and elective surgery be delayed for up to six months.

Reconstructive microsurgery can be successfully applied to major defects of the lower back and posterior pelvis. When present, the superior and inferior gluteal vessels can be excellent free flap recipient vessels. However, if they are absent as a result of trauma or tumor ablation, a wrist carrier can be used to transfer large blocks of tissue in a staged procedure. Five patients are presented with challenging defects for which these techniques were used.