Hyperbaric hydrogen therapy improves secondary brain injury after head trauma.

Background: The pathophysiology of traumatic brain injury (TBI) is caused by the initial physical damage and by the subsequent biochemical damage (secondary brain injury). Oxidative stress is deeply involved in secondary brain injury, so molecular hydrogen therapy may be effective for TBI. Hydrogen gas shows the optimal effect at concentrations of 2% or higher, but can only be used up to 1.3% in the form of a gas cylinder mixed with oxygen gas, which may not be sufficiently effective. The partial pressure of hydrogen increases in proportion to the pressure, so hyperbaric hydrogen therapy (HBH2) is more effective than that at atmospheric pressure. Methods: A total of 120 mice were divided into three groups: TBI + non-treatment group (TBI group; n = 40), TBI + HBH2 group (n = 40), and non-TBI + non-treatment group (sham group; n = 40). The TBI and TBI + HBH2 groups were subjected to moderate cerebral contusion induced by controlled cortical impact. The TBI + HBH2 group received hyperbaric hydrogen therapy at 2 atmospheres for 90 minutes, at 30 minutes after TBI. Brain edema, neuronal cell loss in the injured hippocampus, neurological function, and cognitive function were evaluated. Results: The TBI + HBH2 group showed significantly less cerebral edema (p ≺ 0.05). Residual hippocampal neurons were significantly more numerous in the TBI + HBH2 group on day 28 (p ≺ 0.05). Neurological score and behavioral tests showed that the TBI + HBH2 group had significantly reduced hyperactivity on day 14 (p ≺ 0.01). Conclusion: Hyperbaric hydrogen therapy may be effective for posttraumatic secondary brain injury.

Cadaver investigation of the usefulness of the transstyloid diaphragm approach for high-position plaque carotid endarterectomy.

OBJECTIVES: Patients sometimes present with high cervical internal carotid artery (ICA) stenosis. This study demonstrates the usefulness of the transstyloid approach to expose the distal ICA by dissection of the styloid diaphragm covering the distal cervical ICA for carotid endarterectomy (CEA). In particular, the possible exposure length achieved by this approach was investigated using cadaveric heads. METHODS: The procedure of the transstyloid diaphragm approach was confirmed in 10 cadaveric heads (20 sides). After the carotid triangle was opened, both the posterior belly of the digastric muscle (PBDM) and the stylohyoid muscle could be divided. Then, the carotid sheath was dissected, and the glossopharyngeal nerve was identified crossing over the distal ICA. The revealed length of the ICA was measured with or without dissection of both the PBDM and the stylohyoid muscle. The specimens were dissected under the surgical microscope. RESULTS: The transstyloid diaphragm approach was achieved successfully in all specimens. The revealed lengths of the ICA with and without dissection of the styloid diaphragm were 53.7 ± 5.9 mm and 38.8 ± 2.9 mm (mean ± standard deviation), respectively. Therefore, the revealed length of the distal ICA was 14.9 ± 4.5 mm greater using the transstyloid diaphragm approach compared to the regular CEA approach. CONCLUSIONS: More of the ICA can be revealed by dissection of both the PBDM and the stylohyoid muscle. The transstyloid diaphragm approach might be helpful to reveal the distal ICA in cases of high cervical ICA stenosis.

Systematic Review of Spinal Lymphomatoid Granulomatosis Cases.

Lymphomatoid granulomatosis (LYG) is a rare Epstein-Barr virus-associated systemic angiocentric and angiodestructive lymphoproliferative disorder. It commonly involves the lungs and can also affect the skin, liver, kidney, and central nervous system. It can rarely occur in the spine, however, the details are unclear. We performed a systematic review of published cases (including our 1 case) of spinal LYG. We performed a systematic search of studies in English on spinal LYG, focusing on its clinical features, imaging, and treatments, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines on the PubMed database. We identified 14 patients from the literature. We also found 1 case of isolated cervical LYG (grade 3) who was treated with steroid and radiation therapy for the spinal lesion after pathologic diagnosis. We performed a pooled analysis of these 15 cases. The mean age was 43.4 years, and 13 of the 15 patients were male. Brain lesions were present in 11 of 12 intramedullary spinal lesions, and only 1 was an isolated spinal LYG case. Regarding the diagnostic methods, 1 case was not described. Of the 14 cases described, 12 patients underwent biopsies (7 brain, 4 lung, and 1 spinal cord lesion) and 2 underwent surgical removal for an extramedullary lesion. In the overall prognosis from a mean follow-up period of 21.6 months, 4 patients died despite several treatments. Spinal LYG, particularly isolated spinal LYG, is rare. Thus further accumulation of cases may be necessary to better understand its characteristics.

An intraoperative motor tract positioning method in brain tumor surgery: technical note.

Intraoperative 3D recognition of the motor tract is indispensable to avoiding neural fiber injury in brain tumor surgery. However, precise localization of the tracts is sometimes difficult with conventional mapping methods. Thus, the authors developed a novel brain mapping method that enables the 3D recognition of the motor tract for intrinsic brain tumor surgeries. This technique was performed in 40 consecutive patients with gliomas adjacent to motor tracts that have a risk of intraoperative pyramidal tract damage. Motor tracts were electrically stimulated and identified by a handheld brain-mapping probe, the NY Tract Finder (NYTF). Sixteen-gauge plastic tubes were mounted onto the NYTF and inserted in the estimated direction of the motor tract with reference to navigational information. Only the NYTF was removed, leaving the plastic tubes in their places, immediately after muscle motor evoked potentials were recorded at the minimum stimulation current. Motor tracts were electrically identified in all cases. Three-dimensional information on the position of motor tracts was given by plastic tubes that were neurophysiologically placed. Tips of tubes showed the resection limit during tumor removal. Safe tumor resection with an arbitrary safety margin can be performed by adjusting the length of the plastic tubes. The motor tract positioning method enabled the 3D recognition of the motor tract by surgeons and provided for safe resection of tumors. Tumor resections were performed safely before damaging motor tracts, without any postoperative neurological deterioration.

Acute Poststroke Depression Is Associated with Thalamic Lesions and Clinical Outcomes: A Case-Control Study.

BACKGROUND: We investigated the role of acute-phase stroke lesions and patient characteristics in poststroke depression (PSD) and its effect on the clinical outcome. PATIENTS AND METHODS: Five and 30 days after admission, 175 patients self-reported their depressive symptoms on the Patient Health Questionnaire-9. We compared the clinical characteristics and outcomes in patients with (n = 41) and without PSD (n = 134). Stroke severity was assessed with the National Institutes of Health Stroke Scale (NIHSS); the modified Rankin Scale (mRS) was used to determine the functional outcome. RESULTS: There was no significant difference between patients with and without PSD in the age, gender ratio, lesion side, and the history of hypertension, diabetes mellitus, alcohol and tobacco use, and previous stroke. Thalamic lesions were significantly associated with PSD (P = .03), although there was no significant difference in both the NIHSS score and the final mRS score of patients with thalamic lesions. Backward stepwise logistic regression analysis showed that a higher NIHSS score and thalamic lesions were independent predictors of PSD. Total hospitalization was significantly longer in patients with PSD. At the time of admission, the NIHSS score was significantly higher in patients who developed moderate to severe PSD than in those with mild PSD or without PSD. CONCLUSIONS: PSD in the acute phase was associated with thalamic lesions and severe stroke. Hospitalization was significantly longer in patients with PSD and their functional disability was more severe, suggesting that PSD played a role in the unsatisfactory results of poststroke rehabilitation.

Transarticular fixation with a bioabsorptive screw for cervical spondylolisthesis.

OBJECTIVE: Patients with cervical instability and intramedullary signal intensity changes on preoperative magnetic resonance imaging scans may benefit from not only cervical decompression but also from fusion surgery. Transarticular screw (TAS) fixation is a useful technique for posterior fixation. We first report treating a patient with cervical spondylosis and instability by cervical laminoplasty with TAS fixation using a bioabsorptive screw. METHODS: A 66-year-old woman who had undergone surgery for carcinoma of the tongue via the anterior approach experienced cervical myelopathy. Radiologic findings showed severe cervical canal stenosis with myelomalacia and spondylolisthesis at C4/C5 with instability. RESULTS: We performed laminoplasty of C3 to C7 and TAS fixation of C4/C5 using a bioabsorptive poly-L-lactide screw that contained hydroxyapatite. Her postoperative course was uneventful, and at 1 year after treatment we confirmed C4/C5 fusion. CONCLUSIONS: Our method has advantages over metal instrumentation. The treated area can be evaluated with the use of magnetic resonance imaging, and the space left after screw absorption is filled by newly formed bone. Because our screw contains hydroxyapatite, it is osteoconductive. This may increase the fusion rate and induce substitution with new bone. To our knowledge this is the first patient treated by cervical posterior TAS fixation via the use of a bioabsorptive screw. Our method is safe and economical and free of the complications elicited by the use of metal parts. TAS fixation with a bioabsorptive screw may be appropriate for one fixation in patients without severe instability.

Clinical features of myocardial triglyceride in different types of cardiomyopathy assessed by proton magnetic resonance spectroscopy: comparison with myocardial creatine.

BACKGROUND: Myocardial lipid overstorage may produce cardiomyopathy, leading to dysfunction, but advanced heart failure may cause lipolysis via sympathetic nerve activation. In the failing heart, the creatine kinase system may also be impaired. The aims of this study were to assess myocardial triglyceride (TG) and creatine (CR) in different types of cardiomyopathy and to investigate whether they are related to the severity of cardiac dysfunction. METHODS AND RESULTS: In patients with hypertrophic cardiomyopathy (HCM, n = 8), dilated cardiomyopathy (DCM, n = 12) or ischemic cardiomyopathy (ICM, n = 10), and normal subjects (NML, n = 22), myocardial TG and CR were evaluated using proton magnetic resonance spectroscopy. To assess cardiac sympathetic nerve activity, myocardial MIBG (a radioactive guanethidine analog) uptake was measured in DCM. Myocardial TG was significantly lower in hypertrophic cardiomyopathy (HCM) (1.92 ± 0.99 µmol/g), but higher in ICM (7.59 ± 4.36 µmol/g) than in NML hearts (4.05 ± 1.94 µmol/g). There was no significant difference in TG between DCM (4.84 ± 6.45 µmol/g) and NML. Myocardial CR in HCM (20.4 ± 8.4 µmol/g), DCM (14.8 ± 4.8 µmol/g), and ICM (19.4 ± 6.3 µmol/g) was significantly lower than that in NML hearts (27.1 ± 4.3 µmol/g). Overall, myocardial CR correlated positively with the severity of heart failure estimated by ejection fraction or myocardial BMIPP (a radioactive fatty acid analog) uptake, but TG did not. In DCM, myocardial TG correlated with body mass index, but not with MIBG uptake. CONCLUSIONS: Myocardial TG may be related to the specific cause of disease rather than the severity of cardiac dysfunction. In contrast, myocardial CR reflects the severity of heart failure despite different pathoetiologic mechanisms of dysfunction. In DCM, myocardial TG may be affected by an overweight state rather than cardiac sympathetic nerve dysfunction. Thus, myocardial CR has a closer relationship to heart failure severity than does myocardial TG.

Pilomyxoid astrocytoma of the fourth ventricle in an adult.

Pilomyxoid astrocytomas have been identified as a variant of pilocytic astrocytoma. They are listed as a novel clinico-pathological entity in the 2007 World Health Organisation (WHO) classification of tumours of the central nervous system. This tumour corresponds to a WHO grade II neoplasm whereas pilocytic astrocytoma corresponds to WHO grade I. We have encountered an infratentorial tumour with pilomyxoid features in an adult. A 25 year old man presented with tinnitus and hyperacusis. Brain MRI revealed a mass occupying the fourth ventricle. We performed partial resection, but no adjuvant therapy was given. The staining index for the anti-Ki-67 monoclonal antibody MIB-1 was less than 1% in this patient. Pilomyxoid astrocytomas are not limited to the hypothalamic/chiasmatic region in children. Additional knowledge and recognition of this entity is necessary to improve treatment of pilomyxoid astrocytoma.

Proton magnetic resonance spectroscopy can detect creatine depletion associated with the progression of heart failure in cardiomyopathy.

OBJECTIVES: This study noninvasively examined total creatine (CR) of the myocardium in dilated cardiomyopathy (DCM) or hypertrophic cardiomyopathy (HCM) using proton magnetic resonance spectroscopy ((1)H-MRS). BACKGROUND: Abnormalities in CR metabolism in failing hearts have been reported. A biochemical study suggested that myocardial metabolic changes are very similar in DCM and HCM despite the different heart failure (HF) mechanisms. METHODS: Using cardiac-gated (1)H-MRS with magnetic resonance image (MRI)-guided point-resolved spectroscopy (PRESS) localization, we quantitatively measured septal CR. Patients with either DCM (n = 11) or HCM (n = 7) and age-matched normal subjects (n = 14) were examined. RESULTS: Myocardial CR was significantly lower in DCM patients (16.1 +/- 4.5 micromol/g wet weight [range 10.2 to 22.9], p < 0.05) than that in subjects with normal hearts (27.6 +/- 4.1 micromol/g [range 21.4 to 36.2]). Myocardial CR in HCM patients (22.6 +/- 8.1 micromol/g [range 12.2 to 34.5]) was significantly lower than that in subjects with normal hearts (p < 0.05) but was significantly higher than that in DCM patients (p < 0.05). In 18 patients with either DCM or HCM, myocardial CR correlated positively with left ventricular ejection fraction (LVEF) (y = 0.22x + 9.8, r = 0.73, p = 0.0006) but correlated negatively with plasma B-type natriuretic peptide (BNP) levels (y = -0.012x + 22.4, r = -0.54, p = 0.022). CONCLUSIONS: This study showed that (1)H-MRS can noninvasively detect CR depletion associated with the severity of HF in cardiomyopathy.

Endothelial modulation and tolerance development in the vasorelaxant responses to nitrate of rabbit aorta.

We investigated the endothelial modulations in nitrate tolerance in isolated rabbit aorta. Nitrate tolerance was induced by a 72-h treatment with transdermal nitroglycerin (NTG, 0.4 mg/h) in conscious rabbits, which was verified by a 20-fold increase in the EC50 values [NTG tolerance (6.1 +/- 0.8) x 10(-7) M vs control (3.0 +/- 0.6) x 10(-8) M]. The relaxations to NTG in tolerant and nontolerant aortic strips were enhanced when their endothelia were denuded [E(-)]. In the presence of endothelium [E(+)], NTG-tolerant vessels were not tolerant to acetylcholine (ACh), which can release endothelial nitric oxide (NO), exogenous NO or 8-bromo (Br)-cGMP. In NTG-tolerant and nontolerant vessels with endothelium, concentration-response curves for NO were the same as those in endothelium-absent tolerant vessels. In both NTG-tolerant and nontolerant vessels, treatment with superoxide dismutase (SOD, 20 units/ml), an O2-. scavenger, unaffected the responses to NTG reduced in the presence of endothelium, but treatment with NG-nitro-L-arginine methyl ester (L-NAME, 10(-4) M), an NO synthase (NOS) inhibitor, reversed these reductions. Thus, our data did not indicate that an increased endothelial superoxide O2-. production contributes to nitrate tolerance. Our study suggested that (i) an impaired biotransformation process from NTG to NO is responsible for the occurrence of nitrate tolerance and (ii) vascular response to NTG enhanced by endothelial removal is related to blocked endothelial NO release.

Polyphosphate produced in recombinant Escherichia coli confers mercury resistance.

An Escherichia coli strain was generated by fusion of a merA-deleted broad-spectrum mer operon from Pseudomonas K-62 with a bacterial polyphosphate kinase gene (ppk) from Klebsiella aerogenes in vector pUC119. A large amount of the ppk-specified polyphosphate was identified in the mercury-induced bacterium with the fusion plasmid designated pMKB18 but not in the cells without mercury induction. These results suggest that the synthesis of polyphosphate as well as the expression of the mer genes is mercury-inducible and regulated by merR. The E. coli strain with pMKB18 was more resistant to both Hg2+ and C6H5Hg+ than its isogenic strain with cloning vector pUC119. The recombinant strain accumulated more mercury from Hg2+- and C6H5Hg+-contaminated medium. Hg2+ transported into the cytoplasm appeared to be bound by chelation with the polyphosphate produced by the recombinant cells. The transported phenylmercury was degraded to Hg2+ before the chelation since polyphosphate did not directly chelate with C6H5Hg+. These results indicate that polyphosphate is capable of reducing the cytotoxicity of the transported Hg2+ probably via chelation between polyphosphate and Hg2+.

Application of the partial 16S rDNA sequence as an index for rapid identification of species in the genus Bacillus.

A comparison of 16S rRNA gene (rDNA) sequences was made among type strains of 69 Bacillus species approved in the International Journal of Systematic Bacteriology (IJSB) until 1998. The results suggested that 5' end region (approx. 275 bp) was the hypervariant region (HV region) in the gene and was highly specific for each type strain. Furthermore, a sequence analysis of the HV region of Bacillus strains revealed that this region was highly conserved within the species. These results indicate that the HV region is a useful index for the identification or grouping of Bacillus species.