Multidisciplinary Approach to Complicated Crown-root Fracture Treatment: A Case Report.

Treatment of complicated crown-root fractures is one of the most challenging within the various types of dental trauma and requires a multidisciplinary approach. This paper reports the complicated crown-root fracture of a maxillary right central incisor, in which there was esthetic, functional, and biologic (endodontic and biologic width invasion) involvement. A 15-year-old male patient presented to the dental clinic one month after suffering trauma with a complicated crown-root fracture on tooth 8. The patient had previously undergone endodontic treatment and was sent to have periodontal surgery to reestablish the biological width on the palatal surface. Following the surgery, a fiberglass post was cemented, and the fragment was reattached. This approach allows the exposure of the cervical margin, adequate isolation, and subsequent fragment reattachment in the same clinical appointment. Fragment reattachment is a viable approach as it is a simple and conservative procedure that restores the natural esthetic of the tooth and has superior resistance compared to a composite restoration. The patient's cooperation in understanding the limitations of the treatment and maintaining adequate oral hygiene are very important to achieving a good prognosis of the case. After a 2-year clinical and radiographic follow-up period, the clinical protocol was found to be successful, and the tooth remained functional, esthetically favorable and asymptomatic.

Changes in oxalate and some mineral concentrations of Setaria sphacelata under cutting and uncutting conditions.

Oxalate concentration in forage plants is important, because it results mineral deficiency in ruminants. Data on oxalate concentration in forage plants in conjunction with cutting and uncutting conditions throughout the growing period are limited. This study was aimed to investigate the changes in oxalate and some mineral concentrations of setaria (Setaria sphacelata). The plants were harvested at different stages (vegetative, boot, pre-flowering, flowering and seed) of maturity and at about 50 cm in length of regrowth (second to sixth cuttings) for evaluation of soluble oxalate, insoluble oxalate and some mineral concentrations. Soluble oxalate and total oxalate concentrations, as well as mineral concentrations, decreased with advancing maturity. Both oxalate concentrations (soluble or insoluble) were higher in leaf compared to stem. Soluble oxalate and total oxalate concentrations of regrowth were the highest at third cutting and lowest at sixth cutting. Insoluble oxalate concentration of regrowth was almost similar in all cuttings, except for the sixth cutting. The highest concentrations of potassium, sodium and magnesium of regrowth were observed at third cutting, while the highest concentration of calcium was observed at sixth cutting. A relationship between oxalate and mineral concentrations was partially observed. Results suggest that cutting materials of setaria from June to October could achieve oxalate levels that are toxic to ruminants.

Legionella pneumophila contamination in a steam towel warmer in a hospital setting.

For prevention of nosocomial legionellosis, environmental investigation to identify possible infectious sources is essential. An environmental study in a ward of our hospital revealed that a steam towel warmer was contaminated with legionella whereas no legionella was detected in tap water supplies and shower heads. Water in the apparatus may be a reservoir of legionella. We abandoned the use of all steam towel warmers in our hospital. Based on this finding, we recommend that steam towel warmers in hospital settings be avoided. Otherwise, the apparatus should be drained, cleaned and dried every day.

Inhibition of intracellular hepatitis C virus replication by nelfinavir and synergistic effect with interferon-alpha.

Liver diseases associated with hepatitis C virus (HCV) infection have become the major cause of mortality in patients with human immunodeficiency virus (HIV) infection since the introduction of highly active anti-retroviral therapy. HCV-related liver disease is more severe in HIV-infected patients than in non-HIV-infected patients, but the standard therapies used to treat chronic hepatitis C in HCV/HIV coinfected patients are the same as those for patients infected with HCV alone. HIV protease inhibitors might have potential to down-regulate HCV load of HCV/HIV coinfected patients. In this study, we evaluated the effects of nelfinavir on intracellular HCV replication using the HCV replicon system. We constructed an HCV replicon expressing a neomycin-selectable chimeric firefly luciferase reporter protein. Cytotoxicity and apoptosis induced by nelfinavir were assessed and synergism between nelfinavir and interferon (IFN) was calculated using CalcuSyn analysis. Nelfinavir dose-dependently repressed HCV replication at low concentrations (IC(50), 9.88 micromol/L). Nelfinavir failed to induce cytotoxicity or apoptosis at concentrations that inhibited HCV replication. Clinical concentrations of nelfinavir (5 micromol/L) combined with IFN showed synergistic inhibition of HCV replication in our replicon model. Our results suggest that the direct effects of nelfinavir on the HCV subgenome and its synergism with IFN could improve clinical responses to IFN therapy in HCV/HIV coinfected patients.

Detection of legionella species in clinical samples: Comparison of polymerase chain reaction and urinary antigen detection kits.

BACKGROUND: Recently, two excellent methods have been used for the diagnosis of Legionnaires' disease: urinary antigen detection and PCR. The purpose of the present study is to analyze and evaluate the sensitivity and specificity of three different urinary antigen detection kits as well as PCR. MATERIALS AND METHODS: A total of 148 samples were collected from 33 patients between 1993 and 2004. These consisted of 73 urine samples obtained from 33 patients, 57 serum samples provided by 29 patients, and 18 respiratory tract specimens from 13 patients. Three commercially available kits were used to detect urinary antigen. For the 5S PCR reaction, primers L5SL2 and L5SR84 were used. RESULTS: Positive results were shown in all patients' urine (representing 79.5% of total samples) using the Binax EIA kit, in 93.9% patients (representing 75.3% samples) using the Binax NOW immunochromatographic kit, and in 90.9% (representing 72.6% samples) using the Biotest EIA kit. Urine samples from 12.1% patients (representing 6.8% of total samples), serum samples from 41.4% patients (representing 35.1% of total samples), and respiratory samples from 84.6% patients (representing 88.9% of total samples) showed positive results with PCR. CONCLUSION: In testing urine of legionellosis patients, it was suggested that three kits were all valuable tools for diagnosis of legionellosis. Since over one-third of patients' serum samples and most respiratory specimens showed positive results with PCR, the addition of PCR for testing of these samples might be useful, particularly in cases of culture negative and serum antibody negative patients.

HRCT shows variations in appearance in disseminated tuberculosis in adults.

OBJECTIVE: To examine patterns of high resolution computed tomography (HRCT) of lungs of adults with disseminated tuberculosis (TB). DESIGN: Disseminated TB was defined as radiological involvement of all lung lobes. RESULTS: The case series illustrated wide variation in HRCT of disseminated TB. Patterns identified on HRCT included (1) miliary TB (haematogenous dissemination), (2) miliary TB with exudative reaction, (3) bronchogenic spread, (4) miliary TB mixed with bronchogenic spread, and (5) bronchogenic spread with multiple cavity formation. CONCLUSION: The HRCT patterns described allow classification of disseminated TB according to the mechanism of spread (haematogenous and/or bronchogenic) and the degree of local lung involvement (reaction or cavitation).

Structural effects of an LQT-3 mutation on heart Na+ channel gating.

Computational methods that predict three-dimensional structures from amino acid sequences have become increasingly accurate and have provided insights into structure-function relationships for proteins in the absence of structural data. However, the accuracy of computational structural models requires experimental approaches for validation. Here we report direct testing of the predictions of a previously reported structural model of the C-terminus of the human heart Na(+) channel. We focused on understanding the structural basis for the unique effects of an inherited C-terminal mutation (Y1795C), associated with long QT syndrome variant 3 (LQT-3), that has pronounced effects on Na(+) channel inactivation. Here we provide evidence that this mutation, in which a cysteine replaces a tyrosine at position 1795 (Y1795C), enables the formation of disulfide bonds with a partner cysteine in the channel. Using the predictions of the model, we identify the cysteine and show that three-dimensional information contained in the sequence for the channel protein is necessary to understand the structural basis for some of the effects of the mutation. The experimental evidence supports the accuracy of the predicted structural model of the human heart Na(+) channel C-terminal domain and provides insight into a structural basis for some of the mutation-induced altered channel function underlying the disease phenotype.

Stimulation of protein kinase C inhibits bursting in disease-linked mutant human cardiac sodium channels.

BACKGROUND: Mutations in SCN5A, the gene coding for the human cardiac Na+ channel alpha-subunit, are associated with variant 3 of the long-QT syndrome (LQT-3). Several LQT-3 mutations promote a mode of Na+ channel gating in which a fraction of channels fail to inactivate, contributing sustained Na+ channel current (Isus), which can delay repolarization and prolong the QT interval. Here, we investigate the possibility that stimulation of protein kinase C (PKC) may modulate Isus, which is prominent in disease-related Na+ channel mutations. METHODS AND RESULTS: We measured the effects of PKC stimulation on Na+ currents in human embryonic kidney (HEK 293) cells expressing 3 previously reported disease-associated Na+ channel mutations (Y1795C, Y1795H, and DeltaKPQ). We find that the PKC activator 1-oleoyl-2-acetyl-sn-glycerol (OAG) significantly reduced Isus in the mutant but not wild-type channels. The effect of OAG on Isus was reduced by the PKC inhibitor staurosporine (2.5 micromol/L), ablated by the mutation S1503A, and mimicked by the mutation S1503D. Isus recorded in myocytes isolated from mice expressing DeltaKPQ channels was similarly inhibited by OAG exposure or stimulation of alpha1-adrenergic receptors by phenylephrine. The actions of phenylephrine on Isus were blocked by the PKC inhibitor chelerythrine. CONCLUSIONS: We conclude that stimulation of PKC inhibits channel bursting in disease-linked mutations via phosphorylation-induced alteration of the charge at residue 1503 of the Na+ channel alpha-subunit. Sympathetic nerve activity may contribute directly to suppression of mutant channel bursting via alpha-adrenergic receptor-mediated stimulation of PKC.

Dysferlin mutations in Japanese Miyoshi myopathy: relationship to phenotype.

OBJECTIVE: To study dysferlin gene mutations and genotype-phenotype correlations in Japanese patients with Miyoshi myopathy (MM). BACKGROUND: MM is an autosomal recessive distal muscular dystrophy that arises from mutations in the dysferlin gene. This gene is also mutated in families with limb girdle muscular dystrophy 2B. METHODS: The authors examined 25 Japanese patients with MM. Genomic DNA was extracted from the peripheral lymphocytes of the patients. The PCR products of each of 55 exons were screened by single strand conformation polymorphism or direct sequencing from the PCR fragments. RESULTS: The authors identified 16 different mutations in 20 patients with MM; 10 were novel. Mutations in Japanese patients are distributed along the entire length of the gene. CONCLUSIONS: Four mutations (C1939G, G3370T, 3746delG, and 4870delT) are relatively more prevalent in this population, accounting for 60% of the mutations in this study. This study revealed that the G3370T mutation was associated with milder forms of MM and the G3510A mutation was associated with a more severe form.

Oxidative stress and predominant Abeta42(43) deposition in myopathies with rimmed vacuoles.

This study was undertaken to determine the C terminus of amyloid beta protein (Abeta), accumulated in vacuolated muscle fibers, and compare these findings to the level of oxidative stress. Eight patients with myopathies characterized by rimmed vacuoles (RVs) were analyzed. Monoclonal antibodies specific to Abeta40 or Abeta42(43) revealed that the Abeta42(43) immunoreactivity was solely distributed in the vacuolated muscle fibers, and that only a part was also immunopositive for anti-Abeta40. Quantitative analyses in four specimens, in which eight or more vacuolated muscle fibers were observed, revealed that the mean incidence of Abeta42(43)-positive muscle fibers was 79.5+/-6.2% in total vacuolated muscle fibers, whereas that of the Abeta40-positive fibers was 42.9+/-12.6%. The predominance of Abeta42(43) deposition was statistically significant ( P<0.05). Abeta deposition was then compared with the distribution of oxidative nucleic acid damage in muscle fibers using a monoclonal antibody against 8-hydroxy-2'-deoxyguanosine and 8-hydroxyguanosine (8OHdG&G). The cytoplasmic staining for anti-8OHdG&G was found not only in vacuolated muscle fibers, but also in other muscle fibers including morphologically normal ones. Positive staining was completely abolished by RNase pretreatment and, thus, was suggested to reflect an increase of cellular RNA oxidation. The distribution of 8OHdG&G was much broader than the Abeta deposition. These data suggest that Abeta42(43) is predominantly involved in the pathogenesis of muscle fiber degeneration with RVs, and that oxidative damage may precede Abeta deposition in muscle fibers and play a key role in the pathomechanism of myopathies with RVs.

Mutation in the caveolin-3 gene causes a peculiar form of distal myopathy.

The authors describe a patient with sporadic distal myopathy associated with reduced caveolin-3 in muscle fibers in which the muscle atrophy was restricted to the small muscles of the hands and feet. Gene analysis disclosed a heterozygous 80 G-->A substitution in the caveolin-3 gene that was identical to that of reported cases of elevated serum creatine kinase. This patient further demonstrated possible clinical heterogeneity of myopathies with mutations in the caveolin-3 gene.

[Clinical and bacteriological features of 12 cases of liver abscess caused by Streptococcus milleri group].

We described the clinical and bacteriological features of 12 cases of liver abscess caused by Streptococcus milleri group (SMG) during a 6-year period from 1993 to 1998. The gender was 11 males and 1 female with their ages ranging from 39 to 76 years old (mean: 53.4). The common symptoms were fever (100%), abdominal pain (67%), and appetite loss (58%). Nine cases had underlying diseases such as carcinomas and diabetes mellitus. Predominant causes of the liver abscess were cryptogenic (42%) and biliary tract disease (33%). Three patients died of an exacerbation of the carcinoma. Eight cases (67%) was single infection of SMG and no mixed infection with anaerobes. No strains isolated in this series showed resistance against penicillin G and ampicillin. SMG was highly isolated from the blood culture in eight of the 11 cases (73%). Liver abscess should be taken into consideration as one of the causes of SMG septicemia.

[A family of early childhood-onset Charcot-Marie-Tooth disease type 2].

We reported a man and his son with Charcot-Marie-Tooth disease (CMT) type 2. Their age at onset was about 5 years. Their clinical examinations revealed muscle atrophy and weakness of both distal lower limbs, foot-drop, a reduction of the reflex in both Achilles tendons and sensory impairment of the glove and stocking type. Nerve conduction studies revealed remarkably low amplitude of compound muscle action potential compared to conduction velocity. The nerve biopsy of their sural nerves revealed loss of large myelinated fiber. We presumed that the clinical features of their disease were compatible with CMT2A or 2B. DNA analysis of our family members performed with microsatellite markers linked to the candidate regions of CMT2A and 2B, did not show apparent positive results. We speculate that this family was a novel gene locus of CMT type 2.

Inherited Brugada and long QT-3 syndrome mutations of a single residue of the cardiac sodium channel confer distinct channel and clinical phenotypes.

Defects of the SCN5A gene encoding the cardiac sodium channel alpha-subunit are associated with both the long QT-3 (LQT-3) subtype of long-QT syndrome and Brugada syndrome (BrS). One previously described SCN5A mutation (1795insD) in the C terminus results in a clinical phenotype combining QT prolongation and ST segment elevation, indicating a close interrelationship between the two disorders. Here we provide additional evidence that these two disorders are closely related. We report the analysis of two novel mutations on the same codon, Y1795C (LQT-3) and Y1795H (BrS), expressed in HEK 293 cells and characterized using whole-cell patch clamp procedures. We find marked and opposing effects on channel gating consistent with activity associated with the cellular basis of each clinical disorder. Y1795H speeds and Y1795C slows the onset of inactivation. The Y1795H, but not the Y1795C, mutation causes a marked negative shift in the voltage dependence of inactivation, and neither mutation affects the kinetics of the recovery from inactivation. Interestingly, both mutations increase the expression of sustained Na+ channel activity compared with wild type (WT) channels, although this effect is most pronounced for the Y1795C mutation, and both mutations promote entrance into an intermediate or a slowly developing inactivated state. These data confirm the key role of the C-terminal tail of the cardiac Na+ channel in the control of channel gating, illustrate how subtle changes in channel biophysics can have significant and distinct effects in human disease, and, additionally, provide further evidence of the close interrelationship between BrS and LQT-3 at the molecular level.

Neuroreceptors and ion channels as targets of alcohol.

This article represents the proceedings of a symposium at the 2000 ISBRA Meeting in Yokohama, Japan. The chairs were Toshio Narahashi and Kinya Kuriyama. The presentations were (1) Modulation of neuroreceptors and ion channels by alcohol, by T. Narahashi; (2) Inhibition by ethanol of NMDA and AMPA receptor-channels, by P. Illes, K. Wirkner, W. Fischer, K. Mühlberg, P. Scheibler, and C. Allgaier; (3) Effects of ethanol on metabotropic glutamate receptors, by K. Minami; (4) Acute alcohol actions on the 5-HT3 ligand-gated ion channel, by D. Lovinger; (5) Inhibition of NMDA receptors by MK801 attenuates ethanol-induced taurine release from the hippocampus, by F. Lallemand, R.J. Ward, and P. DeWitte; and (6) Effect of ethanol on voltage-operated Ca2+ channels in hepatic stellate cells, by T. Itatsu, Y. Takei, H. Oide, M. Hirose, X. E. Wang, S. Watanabe, M. Tateyama, R. Ochi, and N. Sato.

[A case of potassium-sensitive periodic paralysis with cardiac dysrhythmia controlled with imipramine and acetazolamide].

We report a patient with potassium-sensitive periodic paralysis with cardiac dysrhythmia. The patient was a 16-year-old man. He presented with asymptomatic ventricular dysrhythmia and periodic paralysis when he was 6 and 12 years old, respectively. Physical examination revealed slight dysmorphic features such as hypoplastic mandible, low-set ears and clinodactyly. Through an exercise test, a potassium tolerance test and a muscle biopsy, his illness was diagnosed as potassium-sensitive periodic paralysis with cardiac dysrhythmia. For the treatment of his episodic paralysis, we started acetazolamide, which improved both the incidence and the severity of paralysis. However, the incidence of cardiac dysrhythmia was increased after the use of acetazolamide. Routine anti-arrhythmic drugs such as lidocaine failed to control his ventricular dysrhythmia. Only imipramine showed its efficacy by improving the degree and the incidence of cardiac dysrhythmia without aggravating periodic paralysis. This syndrome is relatively rare and there have been no standard protocols for the treatment. We propose the combination of acetazolamide and imipramine as the first choice for this clinical entity. We also discussed the efficacy of the exercise test. It enabled us to confirm the diagnosis of periodic paralysis safely and easily by recording the change of compound muscle action potential amplitudes.

Properties of voltage-gated Ca(2+) channels in rabbit ventricular myocytes expressing Ca(2+) channel alpha(1E) cDNA.

Using the whole-cell patch-clamp technique, we have studied the properties of alpha(1E) Ca(2+) channel transfected in cardiac myocytes. We have also investigated the effect of foreign gene expression on the intrinsic L-type current (I(Ca,L)). Expression of green fluorescent protein significantly decreased the I(Ca,L). By contrast, expression of alpha(1E) with beta(2b) and alpha(2)/delta significantly increased the total Ca(2+) current, and in these cells a Ca(2+) antagonist, PN-200-110 (PN), only partially blocked the current. The remaining PN-resistant current was abolished by the application of a low concentration of Ni(2+) and was little affected by changing the charge carrier from Ca(2+) to Ba(2+) or by beta-adrenergic stimulation. On the basis of its voltage range for activation, this channel was classified as a high-voltage activated channel. Thus the expression of alpha(1E) did not generate T-like current in cardiac myocytes. On the other hand, expression of alpha(1E) decreased I(Ca,L) and slowed the I(Ca,L) inactivation. This inactivation slowing was attenuated by the beta(2b) coexpression, suggesting that the alpha(1E) may slow the inactivation of I(Ca,L) by scrambling with alpha(1C) for intrinsic auxiliary beta.