Marked lateral deviation of the phrenic nerve due to variant origin and course of the thyrocervical trunk: a cadaveric study.

Phrenic nerve impairment can often lead to serious respiratory disorders under various pathological conditions. During routine dissection of an 88-year-old Japanese male cadaver, a victim of heart failure, we recognized an extremely rare variation of the right thyrocervical trunk arising from the subclavian artery laterally to the anterior scalene muscle. In addition to that, the ipsilateral phrenic nerve was drawn and displaced remarkably laterad by this vessel. We examined all of the branches arising from subclavian arteries, phrenic nerves and diaphragm muscles. The embryological background of this arterial variation is considered. The marked displacement with prolonged strain had a potential to cause phrenic nerve impairment with an atrophic change of the diaphragm muscle. Recently many image diagnostic technologies have been developed and are often used. However, it is still possible that rare variations like this case may be overlooked and can only be recognized by intimate regional examination while keeping these rare variations in mind.

Japanese nurse practitioner practice and outcomes in a nursing home.

AIM: By describing the practice of a Japanese nurse practitioner, this descriptive case study discusses role development and outcomes before and after the intervention. BACKGROUND: One of the first Japanese nurse practitioners intervened at a nursing home during the government-designated trial period for nurse practitioner practice. CONCLUSION: Because of the nurse practitioner's meticulous observation and timely care provision to the residents in collaboration with the physician and the other staff in the facility, comparative data showed improvement in daily health status management of every resident and decreased deterioration of residents' health conditions requiring ambulance transfer and hospitalization.

In vitro splicing analysis showed that availability of a cryptic splice site is not a determinant for alternative splicing patterns caused by +1G-->A mutations in introns of the dystrophin gene.

BACKGROUND: Splicing patterns are critical for assessing clinical phenotype of mutations in the dystrophin gene. However, it is still unclear how to predict alternative splicing pathways in such cases of splice-site mutation in the dystrophin gene. OBJECTIVE: To identify elements determining alternative splicing pathways in intron +1G-->A mutations of the dystrophin gene. RESULTS: We found that exon 25 is spliced out in the +1G-->A mutation in intron 25, resulting in mild Becker muscular dystrophy, and that a cryptic splice site within exon 45 was activated in severe Duchenne muscular dystrophy with a mutation of +1G-->A mutation in 45. Furthermore, in vitro splicing analysis using a pre-constructed expression vector showed that the mutant intron 25 produced one transcript that lacked exon 25. In contrast, the same splice-site mutation in intron 45 produced three splicing products. One product used the same cryptic donor splice site within exon 45 as the in vivo donor site and another product used a cryptic splice site within the vector sequence. Notably, the available cryptic splice site was not activated by the same G-->A mutation of intron 25. CONCLUSION: It was concluded that sequences inserted into the in vitro splicing assay minigene contain cis-elements that determine splicing pathways. By taking other +1G-->A mutations in the introns of the dystrophin gene reported in the literature into consideration, it seems that cryptic splice-site activation is seen only in strong exons. This finding will help to elucidate the molecular pathogenesis of dystrophinopathy and to predict efficiency of induction of exon skipping with antisense oligonucleotides for treatment of Duchenne muscular dystrophy.

Participation of the secreted dipeptidyl and tripeptidyl aminopeptidases in asaccharolytic growth of Porphyromonas gingivalis.

BACKGROUND AND OBJECTIVE: Porphyromonas gingivalis secretes gingipains, endopeptidases essential for the asaccharolytic growth of this bacterium. P. gingivalis also secretes dipeptidyl aminopeptidases (DPPIV and DPP-7) and a tripeptidyl aminopeptidase (PTP-A), although their role in asaccharolytic growth is unclear. The present study was carried out to elucidate the role of these dipeptidyl/tripeptidyl aminopeptidases on the asaccharolytic growth of P. gingivalis. MATERIAL AND METHODS: Knockout mutants for the DPPIV (dpp), dpp7 and/or PTP-A genes were constructed. Brain-heart infusion medium supplemented with sterile hemin and menadione (BHIHM) was used as a complex medium, and the minimal medium used was GA, in which the sole energy source was a mixture of immunoglobulin G and bovine serum albumin. Growth of P. gingivalis was monitored by measuring the optical density of the culture. RESULTS: All knockout mutants for DPPIV, dpp7 and PTP-A grew as well as strain W83 in BHIHM. In GA, growth of single-knockout and double-knockout mutants was similar to that of W83, whereas growth of a triple-knockout mutant (83-47A) was reduced. We purified recombinant DPPIV and recombinant PTP-A from recombinant Escherichia coli overproducers, and purified DPP-7 from the triple-knockout mutant 83-4A. GA supplemented with the three purified dipeptidyl/tripeptidyl aminopeptidases supported the growth of 83-47A. CONCLUSION: DPPIV, DPP-7 and PTP-A contribute to the normal growth of P. gingivalis by cleaving substrate peptides into short-chain polypeptides that are efficient energy sources for P. gingivalis.

An Escherichia coli cyoE gene homologue in thermophilic Bacillus PS3 encodes a thermotolerant heme O synthase.

The cyoE gene of the Escherichia coli bo-type quinol oxidase operon (cyoABCDE) has been previously shown to encode heme O synthase. To demonstrate a catalytic role of a cyoE homologue (the caaE gene) in the gene cluster for caa3-type cytochrome c oxidase of thermophilic Bacillus PS3, we have carried out genetic complementation analysis using the chimeric operon cyoABCD-caaE and heme O synthase assay using the CaaE-overproduced E. coli membranes. We found that the caaE gene encodes a thermotolerant heme O synthase which provides an intermediate for heme A biosynthesis.

Assignment and functional roles of the cyoABCDE gene products required for the Escherichia coli bo-type quinol oxidase.

Cytochrome bo from Escherichia coli belongs to the heme-copper terminal oxidase superfamily and functions as a redox-driven proton pump. In the present study, we examined the functional roles of the cyoABCDE genes, which encode cytochrome bo. We expressed the cyoABCDE genes in minicells using pTTQ18 derivatives and identified subunits II, I, III, and IV of the oxidase complex and heme O synthase as polypeptides with molecular weights of 33,500, 75,000, 20,500, 12,000, and 28,000, respectively. The expression level of heme O synthase (CyoE) was much lower than those of the oxidase subunits and seems to be controlled just tightly enough for the incorporation of heme O into the oxidase complex. To facilitate functional analysis of the gene products, we developed a single copy expression vector pHNF2, a derivative of the F-sex factor. Genetic complementation tests showed that deletions in each gene resulted in nonfunctional enzymes. Western blotting analysis indicated that the expression levels of subunits I and II were not affected by the deletions in the other cyo gene products. However, spectroscopic analyses of the mutant membranes revealed that all the deletions perturbed or eliminated the redox metal centers in subunit I. Present findings suggest that subunits II, III, and IV of the oxidase complex are required for the assembly of the metal centers in subunit I.

The effect of muscle-tone-reducing procedures in athetotic head movements: partial nerve block by lidocaine and surgical release of the neck muscles.

OBJECTIVE: To investigate the effect of muscle-tone-reducing procedures (MTRPs), i.e. partial nerve block by lidocaine (PNB) and surgical release of muscle attachment to bone (SRMAB), on incessant involuntary head movements in athetotic patients. METHODS: Pre/post-MTRP changes in neck-muscle activities, glabella movement and maximum isometric forces of the head were measured in six athetotic patients with severe spondylotic myelopathy resulting from incessant involuntary head movements. RESULTS: Pre/post-MTRP changes in neck-muscle activities resembled those after gamma-block. In four patients, PNB reduced the maximum isometric force by no more than 40% of pre-PNB force, while decreasing the amount of involuntary head movements to 37-65% of the pre-PNB value in the frontal plane. MRSAB reduced the force by less than 40% of pre-SRMAB force in 4 MRSAB tested patients, while decreasing the amount of involuntary head movements to 12-45% of the pre-SRMAB value in all 6 patients. CONCLUSION: MTRPs reduced involuntary head movements significantly while preserving voluntary muscle forces relatively well. PNB and SRMAB procedures have in common the effect of reducing gain in the myotatic reflex pathway by decreasing the excitatory inflows to alpha-motoneurons via muscle spindle Ia-afferents, which resulted from blocking mainly gamma-efferent conduction by PNB, and reducing background tension in muscle spindles by SRMAB.

Mechanism for interference of hydrochlorothiazide with the Kober reaction for determination of urinary estriol in pregnancy.

Investigation of the mechanism of the lowering effect of hydrochlorothiazide, which was administered orally, in the determination of estriol from the pregnancy urine has been carried out. The isolation and determination of the structure of a copolymer formed from estriol and formaldehyde have suggested the mechanism by which, during the acid hydrolysis process of the glucuronide conjugate of estriol, some copolymers of estriol and formaldehyde generated from hydrochlorothiazide, were formed, thus lowering the observed values of the estriol contents in the urine.

Identification of the D-enantiomer of 2-hydroxyglutaric acid in glutaric aciduria type II.

We determined the optical isomer of the 2-hydroxyglutaric acid (2HG) that was elevated in the urine of five Japanese children with a mild form of glutaric aciduria type II (GA2), caused by a deficiency of electron transfer flavoprotein (ETF) or ETF-ubiquinone oxidoreductase (ETF-QO). The D- and L-enantiomers of 2HG were separated by capillary gas chromatography with a combination of (S)-(+)-2-octanol derivatization and chromatography on a DB-1 column. The isomer that was elevated in GA2 patients was predominantly the D-enantiomer, an observation that may serve as an additional marker for the biochemical diagnosis of GA2. D-2HG dehydrogenation, but not L-2HG dehydrogenation is apparently blocked in GA2. A specific D-2HG dehydrogenase or D-2HG-CoA dehydrogenase may be metabolically linked to ETF and ETF-QO in the mitochondria.

Time-dependent changes in the carotenoid composition and preferential binding of spirilloxanthin to the reaction center and anhydrorhodovibrin to the LH1 antenna complex in Rhodobium marinum.

Carotenoids were isolated from the cells of Rhodobium marinum, and their structures were determined by mass spectrometry and 1H nuclear magnetic resonance spectroscopy; the carotenoids include lycopene, rhodopin, anhydrorhodovibrin, rhodovibrin and spirilloxanthin. Time-dependent changes in the carotenoid composition in the reaction center (RC) and the light-harvesting complex 1 (LH1) were traced by high-performance liquid chromatography analysis of the extracts. The carotenoid composition changed according to the spirilloxanthin biosynthetic pathway. However, spirilloxanthin having the longest conjugated chain was always preferentially bound to the RC, and anhydrorhodovibrin and other precursors to the LH1.

Measurement of lung volumes and pulmonary mechanics during weaning of newborn infants with intractable respiratory failure from extracorporeal membrane oxygenation.

Newborn infants with intractable respiratory failure who require extracorporeal membrane oxygenation (ECMO) experience diffuse pulmonary atelectasis shortly after initiation of ECMO. Atelectasis is likely due to the primary lung injury and the reduction of applied inspiratory ventilator pressure when the respirator settings are changed to the "rest settings." These pathophysiologic changes result in a decrease in lung compliance and lung volumes. We hypothesized that improving lung functions observed during ECMO and indicated by an increase in lung volumes will predict successful weaning from ECMO. Sixteen infants (mean +/- SEM: gestational age, 40.3 +/- 0.3 weeks; birth weight, 3.5 +/- 0.1 kg) with meconium aspiration syndrome (n = 13), sepsis (n = 2), and persistent pulmonary hypertension (n = 1) were studied. We measured passive respiratory system mechanics and lung volumes initially during full ECMO support (115 +/- 18 h on ECMO, Study I), and then within 24 h prior to weaning from ECMO (Study II). Respiratory system compliance (Crs), respiratory system resistance (Rrs), functional residual capacity (FRC), and tidal volume (VT) were measured. Prior to Study I lung volumes were too small to be detected. Crs increased between Study I and Study II (0.41 +/- 0.05 to 0.63 +/- 0.05 mL/cmH2O/kg, P < 0.05), and VT increased between Study I and Study II (5.6 +/- 0.6 to 10.4 +/- 0.8 mL/kg, P = 0.0005). FRC increased from 3.6 +/- 1.0 to 7.9 +/- 0.9 mL/kg (P = 0.0001). There was no change in Rrs (88 +/- 8 to 89 +/- 6 cm H2O/L/s, P = 0.9). The combination of Crs > 0.5 mL/cmH2O/kg and FRC > 5 mL/kg was a better predictor (P = 0.0002) of readiness to wean from ECMO than either Crs (> 0.5 mL/cmH2O/kg, P = 0.057) or FRC (> 5 mL/kg, P = 0.007) alone. The combination of FRC and Crs had a sensitivity of 73.3% and specificity of 100% for successful decannulation. We conclude that repeated measurements of FRC and Crs can assess lung recovery and may assist in establishing criteria for successful weaning from ECMO.

Diagnosis of the level and severity of cord lesion in cervical spondylotic myelopathy. Spinal evoked potentials.

Experimental and clinical studies were performed to measure the segmental spinal evoked potential (SEP) of the cervical cord after stimulation of the median nerve, to determine the location, severity, and outcome of cord lesion in patients who had cervical spondylotic myelopathy. The SEP in control subjects consisted of two waves, the primary reactive R-wave and the secondary reactive N-wave. The R-wave related to both the dorsal root potential and the funiculus posterior potential; the N-wave related to the post-synaptic potential in the spinal cord. In the early stages of cervical spondylotic myelopathy, the N-wave weakens or disappears at the level of lesion. Then, as damage progresses, the R-wave also weakens or disappears.

Staged spinal cord decompression through posterior approach for thoracic myelopathy caused by ossification of posterior longitudinal ligament.

STUDY DESIGN: Prospective clinical study of the effect of staged elimination of anatomic factors inhibiting posterior shift of the thoracic spinal cord on the degree of posterior shift of the thoracic spinal cord and its significance in augmenting the safety of ossification of posterior longitudinal ligament (OPLL) manipulation in thoracic OPLL myelopathy. OBJECTIVES: To develop a comprehensive method that enables safe and sufficient decompression of the spinal cord for thoracic OPLL myelopathy. SUMMARY OF BACKGROUND DATA: Decompression of the spinal cord by direct manipulations of thoracic OPLLs, via either anterior or posterior approach, caused some iatrogenic catastrophic spinal cord injuries, and methods to prevent such injuries during surgery have not yet been developed. METHODS: Procedures of elimination of anatomic factors inhibiting posterior shift of the thoracic spinal cord were performed in stages at intervals of between 1 month and 11 years depending on patients' neurologic status. The first stage operation consisted of extensive cervicothoracic laminoplastic decompression with or without posterior longitudinal durotomy, and if the decompression were insufficient, measures for OPLL-spinal cord separation with or without OPLL manipulation were added. RESULTS: All 17 patients with thoracic OPLL myelopathy showed improvements of neurology comparable with those with successful anterior approaches after decompression. The mean follow-up period was 42 months (range 6-101 months). Neurologic improvements persisted for the entire follow-up period in all patients except one patient who developed arachnoid cyst compressing the dorsum of the once-decompressed spinal cord 30 months after surgery. CONCLUSIONS: Staged posterior decompression to eliminate anatomic factors inhibiting posterior shift of the thoracic spinal cord is the safest and the most reliable method of spinal cord decompression to treat thoracic OPLL myelopathy, so far. However, long-term results are required before the methods can be established.

Extradural tethering effect as one mechanism of radiculopathy complicating posterior decompression of the cervical spinal cord.

STUDY DESIGN: This study used anatomical and clinical data to analyze the postoperative tension-status of cervical roots after posterior decompression of the cervical spinal cord. The efficacy of longitudinal durotomy with regard to prevention of postoperative palsy was investigated in a controlled study. OBJECTIVES: To elucidate the mechanism of postoperative radiculopathy and to prevent its occurrence. SUMMARY OF BACKGROUND DATA: Previous anatomical studies by the authors revealed that the posteromedial shift of the dura-root junction following posterior bulging of the cervical dural sac exerted a traction force on the portion of the roots outside the dural sac and reduced the tension on the rootlets inside the dural sac. These traction-related phenomena disappear after longitudinal durotomy. METHODS: Lengths of various parts of an anterior root were measured in 20 Japanese adult cadavers. The shortest pre- and postoperative distances between the anterolateral mid-edge of the spinal cord and dura-root junction were compared, using computed tomography-myelograms of postoperative C5 radiculopathies. The effects of longitudinal durotomy were also investigated in a controlled study involving 118 patients with laminoplasty. RESULTS: The length ratio between the longest and shortest anterior rootlet in each cervical root showed fairly constant values. Clinically, the length of the shortest rootlet could be calculated using a myelogram. Radiographical findings in cases of postoperative radiculopathies suggested increased tension on roots outside the dural sac but not on rootlets inside the dural sac. Application of longitudinal durotomy in a type of lateral opening laminoplasty resulted in the disappearance of postoperative radiculopathy. CONCLUSIONS: An extradural tethering effect was suggested as one mechanism leading to postoperative radiculopathy. Durotomy may be useful in the treatment of postoperative palsy.

Evaluation of cervical cord function in cervical spondylotic myelopathy and/or radiculopathy using both segmental conductive spinal-evoked potentials (SEP).

To evaluate the function of the cervical cord and to diagnose the level and severity of cervical cord lesions in myelopathy, both segmental and conductive spinal evoked potentials (SEP) were measured in 73 patients with cervical spondylotic myelopathy and/or radiculopathy. In normal subjects, segmental SEPs consisted of two waves (R and N waves). Ascending conductive SEPs also consisted of two waves (first and second waves). The function of the cervical cord, including roots, grey matter, and white matter, can be measured by the combined method using both segmental and conductive SEPs, and this allows differentiation among radiculopathy and various types of myelopathy.

Reduction of respiratory system resistance of rabbits with surfactant deficiency using a novel ultra thin walled endotracheal tube.

The ultra thin walled, two-stage endotracheal tube (UTW-TS-ETT) is very flexible, nonkinking, and has a widened extralaryngeal portion. The UTW-TS-ETT has a greater ID/OD (internal diameter/outer diameter) ratio than a comparable standard endotracheal tube (ST-ETT) because of its thinner wall: 0.2-0.25 mm in UTW-TS-ETT, compared to 0.55-0.8 mm in ST-ETT. The authors hypothesized that in an animal model of lung disease, significant reductions in respiratory system resistance (Rrs) of 30-40% would be achieved using the UTW-TS-ETT, compared to Rrs achieved with the comparable ST-ETT. This study compared the pulmonary mechanics of rabbits (N = 17, body weight 3.4-4.7 kg) before and after induction of surfactant deficiency, using either ST-ETT (OD 4.9 mm, ID 3.5 mm) or UTW-TS-ETT (OD 5.0 mm, ID 4.6 mm). Animals were sedated, paralyzed, and ventilated by an ETT placed through a tracheotomy incision. Surfactant deficiency was induced by lavaging the lungs with normal saline (10 ml/kg). Pulmonary mechanics were measured on identical ventilator settings for each ETT used at baseline and at 45 min after lavage. Compared to ST-ETT, UTW-TS-ETT reduced Rrs by 50.6 +/- 8.7% in normal lungs (significantly more than 40%; p < 0.01), and by 41.47 +/- 16.2% in surfactant deficient lungs (significantly more than 30%; p < 0.05). Tidal volume increased with UTW-TS-ETT in all animals but did not achieve statistical significance. The UTW-TS-ETT did not induce significant changes in respiratory system compliance, PaO2, PaCO2, or pH. It is concluded that UTW-TS-ETT significantly reduces Rrs in rabbits with either normal lungs or with surfactant deficient lungs. This novel ETT may be beneficial for ventilated patients with increased Rrs, by effecting a decrease in Rrs and thus reducing the work of breathing and improving ventilation efficiency.

Splicing error due to a splice acceptor site mutation in the ALD gene identified in a Japanese childhood cerebral adrenoleukodystrophy case.

X-linked adrenoleukodystrophy (ALD) is characterised by progressive multifocal demyelination of central nervous system and adrenocortical insufficiency. This disorder has been also associated with mutations in the ALD gene, encoding an ATP-binding transporter which is located in the peroxisomal membrane. Defect of the gene may lead to impaired peroxisomal beta-oxidation and increase of serum and tissue very long chain fatty acids (VLCFAs). Here we report the results of analysis of the ALD gene in a Japanese patient with childhood cerebral ALD. In our patient, by sequencing of the ALD cDNA, an 8 bp insertion (ACCCCCAG) was detected at the start of exon 9, which corresponded to nucleotides from position -1 to -8 of the 3' splice acceptor site of intron 8. Sequencing of genomic DNA showed a single nucleotide substitution at position-10 of the 3' splice acceptor site of intron 8 replacing a G with an A which activated a cryptic splice acceptor site. It is concluded that a splicing error was induced by a point mutation that created a novel splice acceptor site. This insertion created a nonsense codon downstream, producing a truncated ALD protein. His mother and younger sister with increased VLCFA ratios were heterozygotes of normal and mutant ALD genes.

Phosphorylated polyenols of biochemical interest: cis=trans stereoisomeric retinylphosphates.

All-trans biscyclohexylammonium retinylphosphate was synthesized using bis (triethylammonium) phosphate as the phosphate donor. It was shown to be pure from physico-chemical evidence including ultraviolet, infrared, 1H- and 13C-nuclear magnetic resonance and mass spectrometry. In contrast to previous reports, the synthesized product is quite stable toward alkaline hydrolysis. Direct or iodine-catalyzed photoisomerization of the all-trans compound can produce the corresponding 13-cis isomer. Simultaneous quantification of cis-trans stereoisomeric retinylphosphates was demonstrated by ion-pairing reversed-phase liquid chromatography with an isocratic mobile phase consisting of aqueous methanol and with ultraviolet detection at 300 nm. The mobile phase also contains tetrabutylammoniumphosphate as the counter-ion. The feasibility and extent of stereoisomerization of all-trans retinylphosphate have been compared with those of carotenoidal and retinoidal polyenes.

Thermal stereoisomerization of all-(E)-beta-carotene: (Z)-beta-carotenes and electrocyclized beta-carotenes.

Thermal isomerization of synthetic all-(E)-beta-carotene yielded a multi-component mixture composed of more than sixteen (Z)-beta-carotenes and two thermo-cyclized isomers. They were separated and purified by high-performance liquid chromatography. Ten of these were characterized by spectroscopic methods as four mono-(Z)-, five di-(Z)-, and one tri-(Z)-beta-carotenes; the 7-(Z)-, 9-(Z)-, 13-(Z)-, 15-(Z)-, 9.13-(Z)-, 9.15-(Z)-, 9.13'-(Z)-, 13.15-(Z)-, 7.13'-(Z)-, and 9.9'.13-(Z)-isomers were included. Stereochemistry of six additional (Z)-isomers obtained is, as yet, unknown, though one of them might have the 9.9'-(Z)-geometry in the molecule. This is the first report on the formation and identification of the 'sterically hindered' 7-(Z)-isomers as well as the (5 leads to 10)-thermo-cyclized products in the field of alicyclic carotenoids.

Carbon-13 nuclear magnetic resonance spectra of vitamins D and related compounds.

1. The natural abundance carbon-13 nmr of vitamins D (D2 and D3) and several isomers (5, 6-trans-vitamin D2, isotachysterol2 and isovitamin D2) have been completely assigned by employing off-resonance noise-decoupling, acetylation shifts, and lanthanide-induced shifts experiments. The last two techniques were especially useful for the present study. 2. Carbon-13 nmr spectral characteristics of the three main conjugated triene moieties (SE-Z-SZ, SE-E-SZ, or SE-E-SE), involved in the molecules of vitamin D and its isomers, were revealed. Thus, the striking dependence of the shieldings on molecular geometries and high sensitivity of the resonances to the environments of conjugated systems were surveyed. 3. Conformational preferences in solutions of the hydroxyl groups in vitamins D2 and D3 as well as 5, 6-trans-vitamin D2 were conveniently determined.