14-3-3 proteins regulate intracellular localization of the bZIP transcriptional activator RSG

Gibberellins (GAs) are essential regulators of many aspects of plant development, including stem elongation, seed germination, and flowering. RSG is a transcriptional activator with a basic leucine zipper domain that regulates endogenous amounts of GAs through the control of a GA biosynthetic enzyme. The ubiquitous expression of RSG in plant organs suggests an involvement of post-transcriptional and/or post-translational modifications of the transcription factor. Here, we identify the 14-3-3 signaling proteins as RSG binding partners. The mutant version of RSG that could not bind to 14-3-3 proteins exhibited a higher transcriptional activity than did wild-type RSG. Consistent with this observation, the mutant RSG that could not bind to 14-3-3 proteins was localized predominantly in the nucleus, whereas wild-type RSG was distributed throughout the cell. Using the nuclear export inhibitor leptomycin B, we also showed that RSG, apparently statically localized in the cytoplasm, is capable of shuttling in and out of the nucleus. These results suggest that 14-3-3 proteins negatively modulate RSG, which is involved in the regulation of endogenous amounts of GAs, by controlling its intracellular localization.

14-3-3 proteins regulate intracellular localization of the bZIP transcriptional activator RSG

Gibberellins (GAs) are essential regulators of many aspects of plant development, including stem elongation, seed germination, and flowering. RSG is a transcriptional activator with a basic leucine zipper domain that regulates endogenous amounts of GAs through the control of a GA biosynthetic enzyme. The ubiquitous expression of RSG in plant organs suggests an involvement of post-transcriptional and/or post-translational modifications of the transcription factor. Here, we identify the 14-3-3 signaling proteins as RSG binding partners. The mutant version of RSG that could not bind to 14-3-3 proteins exhibited a higher transcriptional activity than did wild-type RSG. Consistent with this observation, the mutant RSG that could not bind to 14-3-3 proteins was localized predominantly in the nucleus, whereas wild-type RSG was distributed throughout the cell. Using the nuclear export inhibitor leptomycin B, we also showed that RSG, apparently statically localized in the cytoplasm, is capable of shuttling in and out of the nucleus. These results suggest that 14-3-3 proteins negatively modulate RSG, which is involved in the regulation of endogenous amounts of GAs, by controlling its intracellular localization.

Release from or through a wax matrix system. I. Basic release properties of the wax matrix system

Release properties from a wax matrix tablet was examined. To obtain basic release properties, the wax matrix tablet was prepared from a physical mixture of drug and wax powder (hydrogenated caster oil) at a fixed mixing ratio. Properties of release from the single flat-faced surface or curved side surface of the wax matrix tablet were examined. The applicability of the square-root time law and of Higuchi equations was confirmed. The release rate constant obtained as g/min(1/2) changed with the release direction. However, the release rate constant obtained as g/cm2 x min(1/2) was almost the same. Hence it was suggested that the release property was almost the same and the wax matrix structure was uniform independent of release surface or direction at a fixed mixing ratio. However, these equations could not explain the entire release process. The applicability of a semilogarithmic equation was not as good compared with the square-root time law or Higuchi equation. However, it was revealed that the semilogarithmic equation was available to simulate the entire release process, even though the fit was somewhat poor. Hence it was suggested that the semilogarithmic equation was sufficient to describe the release process. The release rate constant was varied with release direction. However, these release rate constants were expressed by a function of the effective surface area and initial amount, independent of the release direction.

The effect of propafenone on premature ventricular contractions (PVC): an analysis based on heart rate dependency of PVCs

The effect of 450 mg/day propafenone for two weeks on premature ventricular contractions (PVCs) was studied in combination with an assessment of heart rate (HR) dependency of PVCs using Holter ECG monitoring in patients with more than 720 PVCs per day. The PVC-HR correlation was classified into positive (P), bidirectional (B), and flat and negative (FN) correlation groups. The positive group included only patients in whom PVC frequency increased with a heart rate increase, while the bidirectional group included patients with PVCs whose frequency increased at low heart rates and decreased at high heart rates. The FN group contained both flat (PVC frequency was almost fixed regardless of heart rate changes) and negative (PVC frequency decreased as heart rate increased) correlations. The effectiveness of propafenone was 70% in the positive group and 50% in the nonpositive group which included both bidirectional (67%) and FN (0%) groups, using a > 70% PVC reduction as a criterion of efficacy. From this, we concluded that propafenone is effective in patients showing either positive or bidirectional PVC-HR correlation. The coupling interval (CI) of PVCs was also prolonged by propafenone as a whole. The present study suggests that there are differences in the mechanism of PVC development in patients with flat or negative correlation and those with a positive or bidirectional correlation. Thus, this type of analysis contributes to an understanding of the action of antiarrhythmic agents, and may allow the prediction of their efficacy on PVCs.

Contrasting effects of zonisamide and acetazolamide on amygdaloid kindling in rats

PURPOSE

Zonisamide (ZNS) and acetazolamide (AZM) are two antiepileptic drugs (AEDs) that differ in clinical efficacy. To elucidate the mechanisms of action of these compounds, we investigated their therapeutic and prophylactic effects in rats by using a kindling model of partial epilepsy.

METHODS

Electrodes were implanted into the left amygdala of adult male Wistar rats. The animals were stimulated at the afterdischarge threshold until five stage 5 seizures were induced. The generalized seizure threshold was then determined. Therapeutic effects were examined in rats manifesting successive convulsions with near-threshold stimulation. To test prophylactic effects, drugs were administered intraperitoneally before daily kindling stimulation until the animal had a stage 5 seizure or reached day 18.

RESULTS

ZNS (10-40 mg/kg; n=6) suppressed kindled seizures in a dose-dependent manner. Repeated administration for 7 days produced tolerance to anticonvulsive effects. AZM (25-200 mg/kg; n=7) showed limited therapeutic effect, alleviating only the clonic convulsion in stage 5 seizures and reducing afterdischarge duration. Secondary generalization was not significantly suppressed during repeated treatment (50-200 mg/kg; n=6). ZNS, 25 or 40 mg/kg (n=8), significantly retarded seizure development; 15.0 or 17.0 daily stimulations were required to produce a stage 5 seizure. AZM, 50-200 mg/kg (n=6), also retarded seizure development, with 14.0-14.8 stimulations required.

CONCLUSIONS

ZNS exhibited modest therapeutic and prophylactic effects, whereas AZM showed mainly prophylactic effects. Hypotheses are presented that may explain the mechanisms of action of these drugs.

Predicting the clinical status of human breast cancer by using gene expression profiles

Prognostic and predictive factors are indispensable tools in the treatment of patients with neoplastic disease. For the most part, such factors rely on a few specific cell surface, histological, or gross pathologic features. Gene expression assays have the potential to supplement what were previously a few distinct features with many thousands of features. We have developed Bayesian regression models that provide predictive capability based on gene expression data derived from DNA microarray analysis of a series of primary breast cancer samples. These patterns have the capacity to discriminate breast tumors on the basis of estrogen receptor status and also on the categorized lymph node status. Importantly, we assess the utility and validity of such models in predicting the status of tumors in crossvalidation determinations. The practical value of such approaches relies on the ability not only to assess relative probabilities of clinical outcomes for future samples but also to provide an honest assessment of the uncertainties associated with such predictive classifications on the basis of the selection of gene subsets for each validation analysis. This latter point is of critical importance in the ability to apply these methodologies to clinical assessment of tumor phenotype.

Adenovirus-mediated transfer of the p53 family genes, p73 and p51/p63 induces cell cycle arrest and apoptosis in colorectal cancer cell lines: potential application to gene therapy of colorectal cancer

p53 gene therapy is being tested clinically for the treatment of human cancer, however, some cancer models (in vivo and in vitro) are resistant to p53. To explore the potential use of two p53 homologues, p73 and p51/p63, in cancer gene therapy, we introduced p53, p73 and p51/p63 into colorectal cancer cell lines via adenoviral vectors, and compared their effects on cell growth. Among 10 cell lines tested, six cell lines displayed a similar response following transduction of p53, p73beta or p51A/p63gamma; two lines underwent cell-cycle arrest, three lines exhibited apoptosis and one line showed no-effect following transduction. The effect on cell-cycle progression was variable in the other four cell lines. Interestingly, three cell lines were resistant to p53-mediated apoptosis, including two lines having endogenous wild-type p53 alleles, but underwent apoptosis after transduction of p73beta or p51A/p63gamma. Similar to p53, transduction of p51A/p63gamma induced extensive apoptosis when combined with adriamycin or X-radiation in SW480 cells, which are normally resistant to apoptosis. Transduction of p73beta and p51A/p63gamma also reduced the tumorigenicity of two colorectal cancer cells in vivo. These results suggest that adenovirus-mediated p73beta and p51A/p63gamma transfer are potential novel approaches for the treatment of human cancers, particularly for tumors that are resistant to p53 gene therapy.

Erythromycin and common cold in COPD

STUDY OBJECTIVES

To investigate whether erythromycin therapy lowers the frequency of the common cold and subsequent exacerbation in patients with COPD.

DESIGN

Prospective, randomized, controlled, but not blinded, trial.

PATIENTS

One hundred nine patients with COPD were enrolled into the study. Patients were randomly assigned to erythromycin therapy or to no active treatment in September 1997. Patients then were observed for 12 months, starting in October, during which time the risk and frequency of catching common colds and COPD exacerbations were investigated. Fifty-five patients received erythromycin at study entry (erythromycin group). The remaining 54 patients received no active treatment (control group).

MEASUREMENTS AND RESULTS

The mean (+/- SE) number of common colds for 12 months was significantly lower in the erythromycin group than in the control group (1.24 +/- 0.07 vs 4.54 +/- 0.02, respectively, per person; p = 0.0002). Forty-one patients (76%) in the control group experienced common colds more than once, compared to 7 patients (13%) in the erythromycin group. The relative risk of developing two or more common colds in the control group compared with that in the erythromycin group was 9.26 (95% confidence interval [CI], 3.92 to 31.74; p = 0.0001). Thirty patients (56%) in the control group and 6 patients (11%) in the erythromycin group had one or more exacerbations. The relative risk of experiencing an exacerbation in the control group compared with that in the erythromycin group was 4.71 (95% CI, 1.53 to 14.5; p = 0.007). Significantly more patients were hospitalized due to exacerbations in the control group than in the erythromycin group (p = 0.0007).

CONCLUSION

Erythromycin therapy has beneficial effects on the prevention of exacerbations in COPD patients.

SOX6 binds CtBP2 to repress transcription from the Fgf-3 promoter

Fgf-3 is expressed in a complex pattern during mouse development. Previously, an essential regulatory element PS4A was identified in the promoter region, and shown to bind at least three factors. To identify the transcription factor(s), we used a yeast one-hybrid screen and obtained a novel Sox6 cDNA (SOX6D). When introduced into cells it strongly repressed activity from both an Fgf-3 reporter gene as well as an artificial promoter containing three PS4A elements. In situ hybridisation analysis showed that Sox6 and Fgf-3 are co-expressed in the otic vesicle of E9.5 mouse embryos in a mutually exclusive pattern, consistent with a repression of Fgf-3 transcription by SOX6. To characterise additional factor(s) involved in Fgf-3 gene repression, a yeast two-hybrid screen was used with the N-terminal portion of SOX6D. Mouse CtBP2 cDNA clones were isolated and shown to bind SOX6 in yeast and mammalian cells. Furthermore, mutational analysis of SOX6 showed that binding to CtBP2, and its responsiveness to this co-repressor, were dependent on a short amino acid sequence motif PLNLSS. Co-expression studies in NIH3T3 cells showed that SOX6 and CtBP2 co-operate to repress activity from the Fgf-3 promoter through the enhancer element PS4A. These results show that SOX6 can recruit CtBP2 to repress transcription from the Fgf-3 promoter.

Decreased bone mass and increased bone turnover with valproate therapy in adults with epilepsy

BACKGROUND

Bone loss and hypovitaminosis D are reported in patients taking antiepileptic drugs, but little is known about changes in bone and calcium metabolism from valproic acid (VPA).

OBJECTIVE

To assess the relationship of VPA to bone mass and calcium metabolism in 40 adults with epilepsy on long-term VPA monotherapy, 40 age- and sex-matched epileptic patients taking phenytoin (PHT), and 40 healthy control subjects. Bone mineral density (BMD) of the second metacarpal was determined as T- and Z-scores.

RESULTS

BMD reduction from control values was 14% (12% in men, 16% in women) with VPA and 13% (12% in men, 15% in women) with PHT. Among patients on VPA, nine (23%) had T-scores below -2.5 SD, suggesting osteoporosis; 15 (37%) had T-scores between -1 and -2.5 SD, suggesting osteopenia. Serum concentrations of calcium were significantly higher with VPA than in PHT or control groups. Serum concentrations of bone Gla protein (a bone formation marker) and pyridinoline cross-linked carboxy-terminal telopeptide of type I collagen (ICTP; a bone resorption marker) associated with either drug significantly exceeded control values. Z-scores for BMD in the VPA group correlated negatively with calcium and ICTP. High ICTP correlated positively with ionized calcium, implying that increased bone resorption caused the latter.

CONCLUSION

Long-term VPA monotherapy can increase bone resorption, leading to decreased BMD.

Manic episode in epilepsy and bipolar I disorder: a comparative analysis of 13 patients

PURPOSE

To determine whether the manic episode of patients with epilepsy has different characteristics from manic episode of patients with bipolar disorder.

METHODS

Interictal manic episodes in patients with epilepsy (epilepsy group) were compared with mood disorders in patients with bipolar I disorder (bipolar group), as defined by the DSM-IV. There were 13 patients (five women and eight men) in each group.

RESULTS

Five epilepsy patients had relatives with epilepsy and/or convulsions, and four bipolar patients had relatives with mood disorders. In the epilepsy group, two had substance-related or organic factors associated with the episodes besides epilepsy, and two exhibited a postictal manic state that had the same symptoms as those of their interictal manic episodes. Ten patients of the epilepsy group had dependent-childish behavior. The epilepsy group had fewer severe mood episodes than the bipolar group. Ten epilepsy patients had fluctuating mood disturbances, and eight had rapid cycling of mood episodes. The epileptogenic zone was in the frontal and/or temporal lobes of eight patients and in multiple lobes of two others; it could not be localized in the three remaining patients.

CONCLUSIONS

The clinical features of the interictal manic episodes in the epilepsy group were different from those in the bipolar group. The manic episodes of the epilepsy group appeared heterogeneous in their causal factors. An epileptogenic zone in the frontal and temporal lobes seems to play an important role in the mood episodes of the majority of patients with epilepsy.

Role for E2F in control of both DNA replication and mitotic functions as revealed from DNA microarray analysis

We have used high-density DNA microarrays to provide an analysis of gene regulation during the mammalian cell cycle and the role of E2F in this process. Cell cycle analysis was facilitated by a combined examination of gene control in serum-stimulated fibroblasts and cells synchronized at G(1)/S by hydroxyurea block that were then released to proceed through the cell cycle. The latter approach (G(1)/S synchronization) is critical for rigorously maintaining cell synchrony for unambiguous analysis of gene regulation in later stages of the cell cycle. Analysis of these samples identified seven distinct clusters of genes that exhibit unique patterns of expression. Genes tend to cluster within these groups based on common function and the time during the cell cycle that the activity is required. Placed in this context, the analysis of genes induced by E2F proteins identified genes or expressed sequence tags not previously described as regulated by E2F proteins; surprisingly, many of these encode proteins known to function during mitosis. A comparison of the E2F-induced genes with the patterns of cell growth-regulated gene expression revealed that virtually all of the E2F-induced genes are found in only two of the cell cycle clusters; one group was regulated at G(1)/S, and the second group, which included the mitotic activities, was regulated at G(2). The activation of the G(2) genes suggests a broader role for E2F in the control of both DNA replication and mitotic activities.

Hepatitis C virus core particle detected by immunoelectron microscopy and optical rotation technique

Hepatitis C Virus (HCV) are 55-65 nm spherical particles, but the internal structure of the virion remains to be clarified. To clarify the morphology of HCV core particles, we performed an immune electron microscopy (IEM) using plasma samples from two blood donors with high HCV RNA titers and a detergent-treated anti-HCV core antibody-free plasma sample with high HCV RNA titer (1.5x10(8) copies/ml). Spherical particles, with 33-40 nm in diameter (an average diameter of 37 nm) were found in 1.22-1.25 g/ml fractions after sucrose density gradient centrifugation by conventional electron microscopy (EM). IEM using rabbit polyclonal antibody (RR8) specific to the putative HCV core protein and goat anti-rabbit IgG colloidal gold particles revealed that these spherical particles specifically reacted with RR8. This finding indicates that the spherical particles are naked HCV core particles. Some of the HCV core particles had an icosahedron-like structure. Optical rotation technique showed that the HCV core particle exhibits six-fold symmetry and that the length of regular hexagon side is approximately 20 nm. These findings showed that HCV core particles are spherical particles of 33-40 nm in diameter and that HCV core particles may possess an icosahedron-like structure and a buoyant density of 1.22-1.25 g/ml.

Exon/intron boundaries, novel polymorphisms, and association analysis with schizophrenia of the human synaptic vesicle monoamine transporter (SVMT) gene

The synaptic vesicular monoamine transporter (SVMT), alternatively vesicular monoamine transporter 2 (VMAT2), pumps cytosolic monoamines including dopamine, norepinephrine, serotonin, and histamine into synaptic vesicles. Altered functions of SVMT have been implicated in the pathogensis of several neuropsychiatric diseases. We determined exon/intron boundaries of the human SVMT gene and performed mutational analysis for the exonic and neighboring intronic regions of the gene. Detected polymorphisms were subject to association analysis with schizophrenia in a family-based design. The human SVMT gene consists, of 16 exons and 15 introns, which is consistent with the murine SVMT gene. When mutational analysis was performed by the single strand conformational polymorphism (SSCP) analysis, we found two and four single nucleotide polymorphisms (SNPs) in exons and neighboring introns, respectively. Neither exonic SNP results in an amino acid change. In family-based association analyses in a sample of 50 Japanese schizophrenics and their parents, no significant association was found for the intronic polymorphisms. Our data suggest that there is no common polymorphism in the SVMT gene affecting the primary structure of the human SVMT protein. Furthermore, we obtained no evidence for the major effect of the novel polymorphisms on susceptibility to schizophrenia.

Posterior Synechia of the Iris After Combined Pars Plana Vitrectomy, Phacoemulsification, and Intraocular Lens Implantation

PURPOSE

Combined pars plana vitrectomy, phacoemulsification, and intraocular lens implantation has become a widely accepted treatment for cataracts in patients with vitreoretinal diseases. We examined factors influencing the development of posterior synechia after this triple procedure.

METHODS

One hundred and three patients (107 eyes) were evaluated. The frequency of postoperative posterior synechia, the preoperative diagnosis, whether gas tamponade was used, and the type of lens implanted were reviewed.

RESULTS

Twenty-one eyes (19.6%) developed posterior synechia, and the highest rate (12/39 eyes, 30.8%) was in patients with proliferative diabetic retinopathy. Posterior synechia was more frequent after gas tamponade (28.1%) than in eyes without tamponade (10.1%). In proliferative diabetic retinopathy (PDR) patients, fibrin deposition and the amount of retinal photocoagulation were causative factors for posterior synechia.

CONCLUSIONS

Factors promoting postoperative synechia after the triple procedure included (1) the existence of PDR, (2) expanding gas tamponade, (3) fibrin deposition in PDR, and (4) the amount of photocoagulation in PDR.

On- and off-responses of the photopic electroretinograms in X-linked juvenile retinoschisis

PURPOSE

To examine the physiologic condition of the middle retinal layer of patients with X-linked juvenile retinoschisis (xlRS) by studying the on- and off-responses of the photopic electroretinograms (ERGs).

METHODS

Eleven unrelated Japanese men (mean age; 24.9 +/- 7.6 years) who were clinically diagnosed with xlRS and molecularly confirmed as having XLRS1 mutations were investigated. For the photopic ERGs, the a-, b- and d-wave amplitudes elicited by long duration stimuli were recorded, and the responses from the xlRS patients were compared to those recorded from normal subjects (n = 14, mean age, 27.5 +/- 4.5 years). We also examined the relationship between the photopic ERG responses and the genotype.

RESULTS

No significant difference was found between the a- and d-wave amplitudes in the xlRS patients (34.2 +/- 8.7 microV, 52.5 +/- 10.4 microV, respectively), and those in normal subjects (40.4 +/- 10.3 microV, 44.7 +/- 6.3 microV, respectively). The mean b-wave amplitude in the xlRS patients was significantly smaller (10.5 +/- 7.7 microV) than the mean of normal subjects (46.4 +/- 10.2 microV) (P < 0.0001). No significant correlation was found between the ERG responses and the locus of the mutation.

CONCLUSION

The photopic ERG demonstrated considerable impairment of the on-pathway arising from an abnormality of the on-bipolar cells or possibly secondary to Müller cell abnormality in xlRS.

Localization of mitochondrial ribosomal RNA on the chromatoid bodies of marine planarian polyclad embryos

Electron-dense cytoplasmic structures, referred to as chromatoid bodies, are observed in the somatic stem cells, called neoblasts, and germline cells in adult planarians. Although it has been revealed that the chromatoid bodies morphologically resemble germline granules in Drosophila and Xenopus embryos, what essential role it plays in the planarian has remained unclear. In the present study, to examine whether chromatoid bodies in planarian embryos are responsible for germline formation, the presence and behavior of chromatoid bodies during embryogenesis were examined. Mitochondrial large ribosomal RNA and mitochondrial small ribosomal RNA were used as candidate markers for components of the chromatoid body. Starting from the fertilized egg, extramitochondrial signals of both RNA (mtrRNA) were observed. At the ultrastructural level, mtrRNA were localized on the surface of the chromatoid bodies. At subsequent stages, the signals of mtrRNA were observed in certain restricted blastomeres that contribute to the formation of larval structures. The signals gradually decreased from the gastrula stage. These results suggest that the chromatoid bodies associated with mtrRNA in embryogenesis are not germline granules. The chromatoid bodies of blastomeres may be concerned with the toti- or pluripotency and cell differentiation as proposed in adult planarian neoblasts.

The stereoselective effects of bucolome on the pharmacokinetics and pharmacodynamics of racemic warfarin

The objective of this study was to investigate the stereoselective influence of bucolome on the pharmacokinetics and pharmacodynamics of warfarin in Japanese inpatients with heart disease. Thirty patients were administered a fixed-maintenance dose of warfarin alone once a day for at least 7 days. The other 25 patients were concomitantly administered warfarin and a 300 mg dose of bucolome once a day, and blood samples were collected on days 1, 4, 7, 14, or 21 after administration of bucolome. Serum concentration of warfarin enantiomers was measured by a chiral reversed-phase HPLC-ultraviolet detection method. The PT-INR was used as a measure of the pharmacodynamic effect of warfarin. Coadministration of bucolome and warfarin had no effect on serum (R)-warfarin concentration and significantly increased serum (S)-warfarin concentration compared with warfarin alone. The PT-INR of warfarin alone was significantly lower with bucolome cotreatment. These results indicate that the augmented anticoagulant effect of warfarin by bucolome is due to inhibition of (S)-warfarin metabolism in vivo. When bucolome is added to a stabilized regimen of warfarin therapy, the dose of warfarin should be reduced by about 30% to 60%, and caution should be exercised during the first 7 days after coadministration of bucolome.

An increase in circulating mast cell colony-forming cells in asthma

We compared a potential to generate mast cells among various sources of CD34(+) peripheral blood (PB) cells in the presence of stem cell factor (SCF) with or without thrombopoietin (TPO), using a serum-deprived liquid culture system. From the time course of relative numbers of tryptase-positive and chymase-positive cells in the cultured cells grown by CD34(+) PB cells of nonasthmatic healthy individuals treated with G-CSF, TPO appears to potentiate the SCF-dependent growth of mast cells without influencing the differentiation into mast cell lineage. CD34(+) PB cells from asthmatic patients in a stable condition generated significantly more mast cells under stimulation with SCF alone or SCF+TPO at 6 wk of culture than did steady-state CD34(+) PB cells of normal controls. Single-cell culture studies showed a substantial difference in the number of SCF-responsive or SCF+TPO-responsive mast cell progenitors in CD34(+) PB cells between the two groups. In the presence of TPO, CD34(+) PB cells from asthmatic children could respond to a suboptimal concentration of SCF to a greater extent, compared with the values obtained by those of normal controls. Six-week cultured mast cells of asthmatic subjects had maturation properties (intracellular histamine content and tryptase/chymase enzymatic activities) similar to those derived from mobilized CD34(+) PB cells of nonasthmatic subjects. An increase in a potential of circulating hemopoietic progenitors to differentiate into mast cell lineage may contribute to the recruitment of mast cells toward sites of asthmatic mucosal inflammation.

[A survey of awareness among new patients at the department of oral diagnosis and general dentistry]

The purpose of this study is to know the outline of clinical statistics of new patients at the Clinic for Initial Diagnosis/Emergency, Dental Hospital, Tokyo Medical and Dental University. We examined 1,001 new patients who visited our hospital from 19 October to 8 December 1995. The results were obtained as follows: 1. Our subjects were 1,001 patients, males were 357(35.7%) and females 644(64.3%). The ratio of male to female was 1:1.8. 2. Concerning age distribution, the majorities were in their twenties and fifties in order. 3. 71.5% of patients said it took less than one hour for them to come to our hospital. 4. The rate of introduced patients was 5.5% of all the new patients.

Paraformaldehyde protects of hepatitis C virus particles during ultracentrifugation

Divergent buoyant densities of hepatitis C virus (HCV) have been reported. If the destruction of HCV particles occurs during the ultracentrifugation process to separate fractions with different densities, an accurate evaluation of the HCV buoyant density is difficult. To examine this concern, changes were examined in HCV RNA titer of each density fraction after paraformaldehyde fixation of virus particles in the sera of 9 patients with chronic HCV infection. Serum was treated with 4% paraformaldehyde, and the density fractions were then separated by ultracentrifugation. The HCV RNA titer of each fraction was determined by reverse transcription-polymerase chain reaction (RT-PCR) assay, and the results were compared with those obtained from the serum without paraformaldehyde fixation. After fixation, the HCV RNA titer was significantly increased in the 1.11-1.14 g/mL fraction (P=0.0018), and decreased in the 1.14-1.17 and 1.17-1.20 g/mL fractions (P=0.0457 and 0.0003, respectively). Using immunogold electron microscopy, it was found that morphologically destroyed HCV particles are present mainly in the 1.17 g/mL fraction of paraformaldehyde-untreated samples, whereas the intact HCV virion particles are present in the 1.12 and 1.14 g/mL fractions of the paraformaldehyde-treated samples. These results suggest that the destruction of HCV virions occurs during the ultracentrifugation process and that paraformaldehyde treatment protects from destruction. It was also considered that the accurate buoyant density of the HCV virion is 1.11-1.14 g/mL. This study describes a useful method for the purification of HCV virions, and provides new insights for elucidating the physicochemical properties of HCV particles.

Familial idiopathic hypoparathyroidism, sensorineural deafness and renal dysplasia

We describe a 27-year-old woman with familial idiopathic hypoparathyroidism, bilateral sensorineural deafness and right renal aplasia. There was a family history of deafness in her father and two other family members with sensorineural deafness, one of whom had hypoparathyroidism. To our knowledge, there have been four previous reports of idiopathic hypoparathyroidism associated with sensorineural deafness and renal dysplasia. The clinical features were not identical to any of the four previous reports. Although no chromosome abnormalities were present in the patient using standard trypsin G-banding analysis, we speculate that some common genetic mutation caused hypoparathyroidism, sensorineural deafness and renal dysplasia.

A significant role of stromal fibroblasts in rapidly progressive dry eye in patients with chronic GVHD

PURPOSE

To elucidate histopathologic features of the lacrimal gland in chronic graft-versus-host disease (GVHD) after allogeneic hematopoietic stem cell transplantation.

METHODS

Lacrimal gland specimens from five patients who had dry eye as part of the symptoms of chronic GVHD were examined by immunohistochemistry and transmission electron microscopy. Lacrimal gland specimens from five patients with Sjögren's syndrome (SS) were used as control samples.

RESULTS

Lymphocytes, predominantly T cells, were found primarily in the periductal areas of the lacrimal gland from patients with chronic GVHD, whereas B cells were the dominant infiltrating cells in the acinar areas of the lacrimal gland from patients with SS. Notable findings in the lacrimal gland from patients with chronic GVHD were marked fibrosis of the glandular interstitium and an increase in the number of CD34(+) stromal fibroblasts. These findings were more prominent in patients with severe dry eye than in those with mild dry eye. Electron microscopic observations of the lacrimal gland from patients with chronic GVHD revealed that stromal fibroblasts were attached to various inflammatory cells, especially T cells, through primitive or rudimentary contacts. In addition, the presence of a well-developed rough endoplasmic reticulum in the fibroblasts and newly synthesized collagen fibrils in the extracellular matrix indicated an active production of extracellular matrix components. Electron micrographs revealed multilayered and thickened basal laminae of blood vessels, ducts, and lobules in the lacrimal gland of patients with chronic GVHD; however, these observations were infrequently observed in the lacrimal glands of patients with SS.

CONCLUSIONS

The results suggest substantial differences in the lacrimal gland histopathology of patients with chronic GVHD and SS. In addition, it is likely that stromal fibroblasts are actively involved in the pathogenic process of chronic GVHD in the lacrimal gland by producing excessive extracellular matrix components.

Postischemic anti-inflammatory effects of bradykinin preconditioning

We sought to determine the mechanisms whereby brief administration of bradykinin (bradykinin preconditioning, BK-PC) before prolonged ischemia followed by reperfusion (I/R) prevents postischemic microvascular dysfunction. Intravital videomicroscopic approaches were used to quantify I/R-induced leukocyte/endothelial cell adhesive interactions and microvascular barrier disruption in single postcapillary venules of the rat mesentery. I/R increased the number of rolling, adherent, and emigrated leukocytes and enhanced venular albumin leakage, effects that were prevented by BK-PC. The anti-inflammatory effects of BK-PC were largely prevented by concomitant administration of a B(2)-receptor antagonist but not by coincident B(1) receptor blockade, nitric oxide (NO) synthase inhibition, or cyclooxygenase blockade. However, NO synthase blockade during reperfusion after prolonged ischemia was effective in attenuating the anti-inflammatory effects of BK-PC. Pan protein kinase C (PKC) inhibition antagonized the beneficial effects of BK-PC but only when administered during prolonged ischemia. In contrast, specific inhibition of the conventional PKC isotypes failed to alter the effectiveness of BK-PC. These results indicate that bradykinin can be used to pharmacologically precondition single mesenteric postcapillary venules to resist I/R-induced leukocyte recruitment and microvascular barrier dysfunction by a mechanism that involves B(2) receptor-dependent activation of nonconventional PKC isotypes and subsequent formation of NO.

Progressive outer retinal necrosis in a patient with nephrotic syndrome

Progressive outer retinal necrosis syndrome (PORN) is a variant of necrotizing herpetic retinopathy and the majority of the described cases were related to acquired immunodeficiency syndrome. We present a patient who is HIV negative with nephrotic syndrome and prednisolone use for 4 months who showed clinical features of PORN. Low CD4 counts and lymphocytopenia suggested immunosuppression. In the left eye, tractional retinal detachment at the posterior pole followed by incomplete posterior vitreous detachment developed. In addition to intravenous administration of acyclovir, vitreous surgeries including stripping of the posterior hyaloid and silicone-oil tamponade were successfully performed to repair the retinal detachment in the left eye and to prevent it in the right eye.

Correlation among fasting plasma glucose, two-hour plasma glucose levels in OGTT and HbA1c

A study was made on the association among 2-h plasma glucose (PG) in oral glucose tolerance test (OGTT), fasting plasma glucose (FPG) using correlation and regression equation. Subjects were 13174 OGTT examinees tested between 1980 and 1998. Blood glucose was determined by the glucose oxidase method and glycated hemoglobin (HbA1c) by the HPLC method. As for correlation between 2-h PG and FPG, regression equation of the <60 year group was y=57.1+0.336x (r=0.866, P<0.0001) and that of the >==60 year group was y=61.5+0.286x (r=0.814, P<0. 0001). FPG was calculated at 124.3 in the <60 year group and 118.7 mg/dl in the >==60 year group for 2-h PG of 200 mg/dl, 2-h PG were calculated at 199.5 and 210.7 mg/dl for FPG of 126 mg/dl, respectively. In the <60 year group, FPG were calculated at 121.7 and 124.4 mg/dl and 2-h PG at 193.2 and 199.3 mg/dl for HbA1c of 6.0 and 6.1%, respectively. As for associations between HbA1c and FPG or 2-h PG being high correlation, it is possible to estimate a prevalence of DM in a group using HbA1c>==6.1%. High correlations were demonstrated among all the three measures; FPG, 2-h PG, HbA1c. If 2-h PG is used in diagnosing diabetes mellitus, an FPG of 126 mg/dl proposed by ADA and World Health Organization (WHO) as a diagnostic level of FPG is an acceptable value for the Japanese.

Dissolution profiles of principal ingredients in Kampo medicinal powders by high-performance liquid chromatography

We describe here a method using HPLC for the simultaneous determination of albiflorin, paeoniflorin, glycyrrhizin and six flavanone glycosides (liquiritin, liquiritin apioside, naringin, neohesperidin, hesperidin and narirutin) in the Kampo medicines, Shigyaku-san and Haino-san. All nine components were separated in less than 40 min by linear gradient elution using a mobile phase containing aqueous phosphoric acid and acetonitrile. The dissolution of these components from powders of Shigyaku-san in aqueous solution at pH 1.80, 4.08 and 6.89 was examined. All of the components except glycyrrhizin were dissolved entirely within 5 min regardless of pH. Dissolution of glycyrrhizin was dependent on the pH of the aqueous solution, and increased with increasing pH.

Clinical characteristics of 14 japanese patients with X-linked juvenile retinoschisis associated with XLRS1 mutation

To characterize the clinical features associated with XLRS1 gene mutations in Japanese patients with X-linked juvenile retinoschisis (xlRS), we evaluated the following data on 14 Japanese males from 13 unrelated families with XLRS1 mutations: age and symptoms at first visit to an ophthalmologist and ophthalmologic findings including visual acuity, refractive errors, fundoscopic appearance, and results of electroretinography (ERG) and electro-oculography (EOG). Each clinical finding was reviewed when the patients were between six and eight years of age. The best-corrected visual acuity in 12 patients (24 eyes) between the ages 6 and 8 years ranged from 1.0 to no light perception. Macular abnormalities were present in all cases. Peripheral retinoschisis was present in 14 of 26 eyes (53.8%). In the 21 eyes for which a single-flash ERG had been recorded, b-wave amplitude was reduced in 17 eyes. The EOG showed a low Arden ratio in three of the 13 eyes in the seven patients evaluated. No clear relationship was observed between the clinical features and the existing mutations. Three of four patients with a visual acuity less than 0.1 had retinal detachment or severe macular lesion that had occurred before the age of four years. Two patients harbored deletions of exon 1 or of the boundary region between exon 3 and intron 3, and one patient harbored R182C in exon 6. The present study shows a heterogeneity of mutations in the XLRS1 gene and phenotypic variations in 14 Japanese patients with xlRS.

E2F4 and E2F5 play an essential role in pocket protein-mediated G1 control

E2F transcription factors are major regulators of cell proliferation. The diversity of the E2F family suggests that individual members perform distinct functions in cell cycle control. E2F4 and E2F5 constitute a defined subset of the family. Until now, there has been little understanding of their individual biochemical and biological functions. Here, we report that simultaneous inactivation of E2F4 and E2F5 in mice results in neonatal lethality, suggesting that they perform overlapping functions during mouse development. Embryonic fibroblasts isolated from these mice proliferated normally and reentered from Go with normal kinetics compared to wild-type cells. However, they failed to arrest in G1 in response to p16INK4a. Thus, E2F4 and E2F5 are dispensable for cell cycle progression but necessary for pocket protein-mediated G1 arrest of cycling cells.

The genomic breakpoint and chimeric transcripts in the EWSR1-ETV4/E1AF gene fusion in Ewing sarcoma

Chromosome translocation creates a fusion between the EWSR1 gene and an ETS family gene. The fusion between these two genes is a characteristic feature of Ewing sarcoma. We previously identified a fourth translocation, t(17;22)(q12;q12), in genomic DNA isolated from cells of patients affected with Ewing sarcoma. The discovery of this translocation suggested that there might be a novel EWSR1-ETV4 fusion gene. In the present study, we determined the genomic breakpoint and characterized the chimeric transcript of the EWSR1-ETV4 fusion gene in two t(17;22) Ewing sarcomas. Reverse transcriptase-PCR assay showed an in-frame fusion between the 5'-terminal region of EWSR1 and the 3' end of ETV4 (alias E1AF, PEA3); the chimeric transcript could thus serve as a template for expression of a protein composed of the N-terminal portion of EWSR1 fused to the DNA-binding domain of ETV4. Long PCR and sequence analysis of genomic DNA revealed that either exon 8 or intron 7 of EWSR1 is fused to the same intron of ETV4 in both tumors. Several palindromic oligomer sequences were found close to the breakpoints in both genes. The 159-bp Alu-like sequence was repeated in the breakpoint region of the ETV4 gene. These observations suggest a mechanism of EWSR1-ETV4 gene fusion.

Clinical factors related to the aqueous levels of vascular endothelial growth factor and hepatocyte growth factor in proliferative diabetic retinopathy

PURPOSE

To investigate clinical factors related to the aqueous humor levels of vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) in patients with proliferative diabetic retinopathy (PDR).

METHODS

Undiluted aqueous humor was obtained during ocular surgery from 46 eyes of 46 patients and the levels of growth factors were measured using enzyme-linked immunosorbent assays. VEGF and HGF levels were compared with the number of photocoagulation. VEGF and HGF levels in patient groups stratified according to the existence of vitreous hemorrhage, retinal detachment, and fibrovascular membrane were analyzed. And clinical parameters associated with the growth factors were determined by multiple regression analysis.

RESULTS

The levels of VEGF decreased significantly as the extent of photocoagulation increased and showed significant positive correlation with the existence of vitreous hemorrhage. There was no significant correlation between VEGF levels and the existence of fibrovascular membrane and traction retinal detachment. The levels of HGF also decreased significantly as the extent of photocoagulation increased, but increased significantly when fibrovascular membrane existed. There were no significant correlations between HGF levels and the existence of vitreous hemorrhage and traction retinal detachment. Concerning systemic conditions, each growth factor has no significant correlation with duration and type of diabetes mellitus, the treatment regimen, the control of hemoglobin A1C, and the existence of hypertension or renal dysfunction.

CONCLUSION

The therapeutic effect of panretinal photocoagulation on PDR might be partly exerted by reduction of the levels of VEGF and HGF in ocular fluid. Since the clinical parameters associated with VEGF were different from those associated with HGF, these growth factors might influence the progression of retinopathy in different ways.

Loss of E2F4 activity leads to abnormal development of multiple cellular lineages

We have generated mice deficient in E2F4 activity, the major form of E2F in many cell types. Analysis of newborn pups deficient in E2F4 revealed abnormalities in hematopoietic lineage development as well as defects in the development of the gut epithelium. Specifically, we observed a deficiency of various mature hematopoietic cell types together with an increased number of immature cells in several lineages. This was associated with an increased frequency of apoptotic cells. We also found a substantial reduction in the thickness of the gut epithelium that normally gives rise to crypts as well as a reduction in the density of villi. These observations suggest a critical role for E2F4 activity in controlling the maturation of cells in a number of tissues.