Prognosis of aortic intramural hemorrhage compared with classic aortic dissection

Aortic intramural hemorrhage occurs fairly frequently among patients with aortic dissection, and may not have a poor prognosis if it is Stanford type B. In patients with type A aortic dissection, cardiac tamponade should be ruled out during observation.

A role for pref-1 and HES-1 in thymocyte development

T lymphocyte development requires a series of interactions between developing thymocytes and thymic epithelial (TE) cells. In this paper we show that TE cells in the developing thymus express Pref-1, a Delta-like cell-surface molecule. In fetal thymus organ cultures (FTOC), thymocyte cellularity was increased by the exogenous dimeric Pref-1 fusion protein, but was reduced by the soluble Pref-1 monomer or anti-Pref-1 Ab. Dimeric Pref-1 in FTOC also increased thymocyte expression of the HES-1 transcription factor. Thymocyte cellularity was increased in FTOC repopulated with immature thymocytes overexpressing HES-1, whereas FTOC from HES-1-deficient mice were hypocellular and unresponsive to the Pref-1 dimer. We detected no effects of either Pref-1 or HES-1 on developmental choice among thymocyte lineages. These results indicate that Pref-1 expressed by TE cells and HES-1 expressed by thymocytes are critically involved in supporting thymocyte cellularity.

Myelinated fibers in Charcot-Marie-Tooth disease type 1B with Arg98His mutation of Po protein

This study was undertaken to characterize the clinical, electrophysiologic, and histopathologic features of five presumably unrelated Japanese patients with Charcot-Marie-Tooth (CMT) disease type 1B and Arg98His substitution of Po protein and, in particular, to correlate Arg98His substitution to the ultrastructural abnormalities of the myelin sheath. Systematic morphometric studies of the sural nerve, where the CMT type 1B gene abnormality is expressed, have not been performed, especially on the basis of the type of mutation causing CMT type 1B. Electrophysiologic evaluation of limb nerves and morphometric analysis of sural nerves obtained at biopsy were performed. Ultrastructural myelin abnormalities were precisely examined. Clinical symptoms appeared from the second to the fifth decade. All probands presented with gait disturbance. Motor and sensory conduction velocities in the median and ulnar nerves ranged from 10 to 30 m/s. Segmental demyelination and remyelination and marked loss of myelinated fibers were the main findings. On electron microscopy, widening between major dense lines was found between the paired intraperiod lines, where the extramembranous portion of the Po protein resides. This widening is probably directly related to Arg98His substitution. Focal uncompaction of major dense lines coexisted with this widening. This uncompaction, which directly decreases the number of myelin lamellae, may be a secondary effect of Arg98His substitution on the intramembranous domain of Po protein. In conclusion, myelin changes at both extracellular and cytoplasmic appositions of Schwann cell membranes were found in association with Arg98His substitution of Po protein. This study contributes to a better understanding of myelin abnormalities in patients with CMT type 1B and Arg98His or other similar extramembranous amino acid substitutions of Po protein.

Indispensability of transmembrane domains of Golgi UDP-galactose transporter as revealed by analysis of genetic defects in UDP-galactose transporter-deficient murine had-1 mutant cell lines and construction of deletion mutants

UDP-galactose transporter is a membrane protein localized in the Golgi apparatus. It translocates UDP-galactose from the cytosol into the Golgi lumen, thus providing galactosyltransferases with their substrate. We characterized murine UDP-galactose transporter through molecular cloning for the following purposes: (i) to elucidate the molecular bases underlying the genetic defects of murine Had-1 mutants, which are deficient in UDP-galactose transporting activity, and (ii) to obtain information that would help us in planning rational approaches to identify functionally essential regions, based on comparison of primary structures between human and murine UDP-galactose transporters. We identified five nonsense mutations, one missense Gly178Asp mutation, and two aberrant splicing mutations. Although glycine178 is highly conserved among nucleotide-sugar transporters, a Gly178Ala variant was functional. The species-differences between human and murine UDP-galactose transporters were largely confined to the N- and C-terminal regions of the transporters. Substantial deletions in the N- and C-terminal regions did not lead to loss of UDP-galactose transporting activity, indicating that these cytosolic regions are dispensable for the transporting activity. The transporter was fused with green-fluorescent protein at the C-terminal cytosolic tail without impairing the functions of either protein. Our results demonstrate the importance of the transmembrane core region of the UDP-galactose transporter protein.

[Kinetic analysis of anti-HIV titer in early stage of HIV infection--a new testing strategy to differentiate early HIV infection individuals from false positive cases]

We analyzed the anti-HIV antibody titer by particle agglutination (PA) on 11 HIV seroconversion panels. PA titer increased very rapidly and the titer went up to 1,000 or more within 18.2 days after seroconversion. The results suggest that one to two weeks of duration will be enough to differentiate persons at the early stage of HIV infection from individuals with HIV screening test initially reactive but false positive. In Japan, HIV prevalence is very low and the majority of the HIV screening test-positive (reactive) cases turned out to be false positive. This HIV testing strategy (one to two weeks interval bleeding) will be very practical and useful to differentiate early stage of HIV infection cases from the majority of false positive cases.

Generation of polymeric immunoglobulin receptor-deficient mouse with marked reduction of secretory IgA

We generated mouse lacking exon 2 of polymeric Ig receptor (pIgR) gene by a gene-targeting strategy (pIgR-deficient mouse; pIgR-/- mouse) to define the physiological role of pIgR in the transcytosis of Igs. pIgR-/- mice were born at the expected ratio from a cross between pIgR+/- mice, indicating that disruption of the pIgR gene in mice is not lethal. pIgR and secretory component proteins were not detected in pIgR-/- mice by Western blot analysis. Moreover, immunohistochemical analysis showed that pIgR protein is not expressed in jejunal and colonic epithelial cells of pIgR-/- mice, whereas IgA+ cells are present in the intestinal mucosa of pIgR-/- mice as well as wild-type littermates. Disruption of the pIgR gene caused a remarkable increase in serum IgA concentration and a slight increment of serum IgG and IgE levels, leaving serum IgM level unaltered. In contrast, IgA was much reduced but not negligible in the bile, feces, and intestinal contents of pIgR-/- mice. Additionally, IgA with a molecular mass of 280 kDa preferentially accumulated in the serum of pIgR-/- mice, suggesting that transepithelial transport of dIgA is severely blocked in pIgR-/- mice. These results demonstrate that dIgA is mainly transported by pIgR on the epithelial cells of intestine and hepatocytes, but a small quantity of IgA may be secreted via other pathways.

Determination of a novel calmodulin antagonist, 3-[2-[4-(3-chloro-2-methylphenyl)-1-piperazinyl]ethyl]-5,6-dimethoxy-1- (4-imidazolylmethyl)-1H-indazole dihydrochloride 3.5 hydrate, DY-9760e, in human plasma using solid-phase extraction and high-performance liquid chromatography with fluorescence detection

A high-performance liquid chromatographic method for the determination of a novel calmodulin antagonist, 3-[2-[4-(3-chloro-2-methylphenyl)-1-piperazinyl]ethyl]-5,6-dimethoxy-1-( 4-imidazolylmethyl)-1H-indazole dihydrochloride 3.5 hydrate, DY-9760e and its major metabolite, 3-[2-[4-(3-chloro-2-methylphenyl)-1-piperazinyl]ethyl]-5,6-dimethoxyi ndazole, DY-9836 in human plasma has been developed. DY-9760e, DY-9836 and the internal standard (I.S.) were extracted from plasma by means of an Isolute C18 (EC) column. The extracts were chromatographed on a reversed-phase TSK-gel ODS-80Ts column using 0.1 M acetate buffer (pH 5)-CH3CN (65:35, v/v) as the mobile phase at a flow-rate of 1.0 ml/min. Fluorescence detection at an excitation wavelength of 303 nm and an emission wavelength of 347 nm resulted in a limit of quantitation of 1.000 ng/ml for plasma. The method showed satisfactory sensitivity, precision, accuracy, recovery and selectivity. Stability studies showed that DY-9760 and DY-9836 were stable in plasma up to at least eight weeks at -80 degrees C.

Thromboembolism originated from the pulmonary artery stump after Fontan operation

Cerebral thromboembolism is a rare but serious complication after Fontan operation. This is the report of a patient who underwent a successful intracardiac thrombectomy for cerebral thromboembolism after Fontan operation. A 2-year-old girl was referred to us with the diagnosis of tricuspid atresia without pulmonary stenosis, normally related great arteries, and a ventricular septal defect. Although she underwent a successful Fontan operation and division of the main pulmonary artery, she developed a cerebrovascular event at 3 weeks after the operation. Echocardiography demonstrated a large thrombus within the residue of the main pulmonary artery, and suggested that the thrombus had migrated into the systemic circulation by way of the ventricular septal defect. At 2 weeks after the cerebrovascular event, she underwent thrombectomy and excision of the pulmonary valve. Although she has developed slight left-sided hemiparesis, she is leading a normal life at 1 year after the operation.

Focal (segmental) dyshidrosis in syringomyelia

The features or mechanisms of dyshidrosis have not been sufficiently clarified. Neither has the difference between hyperhidrosis and hypohidrosis. To clarify the features and mechanisms of dyshidrosis (hyperhidrosis and hypohidrosis) in syringomyelia, the clinical features focusing on hidrosis of 30 patients with syringomyelia and Chiari malformation located from a syringomyelia database were prospectively analysed. The patients were classified into three groups: eight patients (26.7%) had segmental hypohidrosis, 10 (33. 3%) had segmental hyperhidrosis, and 12 (40.0%) had normohidrosis. We found that the Karnofsky functional status for the hyperhydrosis and normohidrosis groups were significantly higher than for the hypohidrosis group (p=0.0012), with no significant differences between the hyperhidrosis and normohidrosis groups. The duration from the onset of syringomyelia to the current dyshidrosis was significantly longer in the hypohidrosis group than in the hyperhidrosis group (p=0.0027). A significant correlation was identified between the duration from the onset of syringomyelia to the time at study and the performance score (r=-0.599, p=0.0003). The results substantiate previous hypotheses that in its early stage syringomyelia causes segmental hyperactivity of the sympathetic preganglionic neurons, and hyperactivity of these gradually subsides as tissue damage progresses. Focal hyperhidrosis may be regarded as a hallmark of a relatively intact spinal cord, as well as normohidrosis.

Mouse model of respiratory syncytial virus infection to evaluate antiviral activity in vivo

In this study, we have developed a practical mouse model for evaluating in vivo the antiviral activity of compounds against respiratory syncytial virus (RSV) infection. BALB/c mice are not particularly susceptible to RSV infection; however, infection rates were improved by pretreatment with the immunosuppressive agent cyclophosphamide (CYP). When mice were inoculated intranasally with RSV A2 strain, the pulmonary RSV titres of CYP-pretreated 10-week-old mice were higher than those of untreated 10-week-old and 28-week-old mice, peaking on days 4 and 5 post-infection. Sections of lung from RSV-infected mice pretreated with CYP, taken on day 4 post-inoculation, showed widespread evidence of interstitial pneumonia and other significant pathological changes. We also confirmed that ribavirin, a representative antiviral agent, significantly reduced the pulmonary RSV titres of mice pretreated with CYP when administered intraperitoneally.

[Dibucaine number (DN) and fluoride number (FN) of L330 I mutant recombinant cholinesterase by use of various substrates]

Dibucaine number (DN) and fluoride number (FN) of the recombinant 330 I mutant ChE (r330 I) expressed in human kidney cells (293 cell) were compared with recombinant usual ChE (rUU), by several assay kits and substrates. All of them showed lower the values compared with rUU. However, the r330 I/rUU ratios about FN determined by several substrates were higher than that determined by propionyl thiocholoneiodide (PTCI), which was recommended by American Association for Clinical Chemistry. In conclusion, commercially available assay kits may not be suitable for the determination of L330 I.

Efficacy of RD3-0028 aerosol treatment against respiratory syncytial virus infection in immunosuppressed mice

RD3-0028, a benzodithiin compound, has antiviral activity against respiratory syncytial virus (RSV) in cell culture. We used a mouse model of RSV infection to determine the in vivo effect of RD3-0028. Cyclophosphamide (CYP)-treated, immunosuppressed mice were inoculated intranasally. The lungs of the mice were removed on day 4. The virus titers of the lungs of RD3-0028-treated mice were compared to the virus titers of the lungs of virus-inoculated, untreated control mice. In an effort to increase the therapeutic effectiveness of this compound, RD3-0028 was administered by aerosol to RSV-infected mice by using a head-exposure system. Aerosols generated from reservoirs containing RD3-0028 (7 mg/ml) administered for 2 h twice daily for 3 days significantly reduced the pulmonary titer of RSV-infected mice. It is clear that the minimal effective dose of RD3-0028 for RSV-infected mice is significantly less than that of ribavirin, the only compound currently available for use against RSV disease. Furthermore, the RD3-0028 aerosol administration appeared to protect the lungs of infected, CYP-treated mice against tissue damage, as evidenced by the preservation of the lung architecture and a reduction in pulmonary inflammatory infiltrates. RD3-0028 aerosol was not toxic for mice at the therapeutic dose. The present study demonstrates the effectiveness of aerosol administration of RD3-0028 for RSV-infected mice.

Production of ex-germfree rabbits for establishment of specific pathogen-free (SPF) colonies

Nine groups of ex-germfree (GF) rabbits were produced by inoculation of hysterectomy-derived GF rabbits with various combinations of cecal bacteria isolated from conventional (CV) rabbits in order to establish a barrier-sustained colony. Six strains of Bacteroides and two strains of Streptococcus isolated from CV rabbits (2 to 3 weeks old) were used for pretreatment. The mortality of ex-GF rabbits inoculated with the anaerobic growth (CF) on EG or SM10 plates inoculated with a 10(-5) dilution of cecal contents was 71.4 to 94.4% when given without pretreatment. All ex-GF rabbits pretreated with Bacteroides alone survived, but the mortality of ex-GF rabbits inoculated with Bacteroides plus Streptococcus strains as pretreatment was 20 and 45.4%. The mortality of ex-GF rabbits inoculated with only Bacteroides was 43%. All ex-GF rabbits inoculated with Bacteroides plus anaerobic growth (CF), cecal suspension of ex-GF mice which had been inoculated with cecal suspensions of CV rabbits (MF) or chloroform-treated cecal suspension (CHF) survived, but CHF inoculated ex-GF rabbits were in an unhealthy condition with slight diarrhoea. These data indicate that inoculation with Bacteroides strains as pretreatment plus CF or MF was required to convert GF rabbits to the normal state.

Establishment of specific pathogen-free rabbit colonies with limited-flora rabbits associated with conventional rabbit flora, and monitoring of their cecal flora

In the present study we attempted to establish specific-pathogen-free (SPF) rabbit breeding colonies with two groups of limited-flora (LF) rabbits, both ex-germfree rabbits, and their offspring. Two groups of LF rabbits associated with cecal flora of conventional (CV) rabbits produced in a previous study [Exp. Animals, submitted], were transferred to individual barrier rooms and some of the LF rabbits were accommodated in isolators to maintain the basic flora for SPF rabbits. The composition of the cecal flora of LF rabbits was stable for a long period; bacteroides remained predominant and clostridia dominant. From the SPF rabbits, different types of bacteria, e.g., enterobacteriaceae and streptococci, which could not be isolated in the isolator were detected at a low population level at an early stage in the establishment of the SPF colonies, but the basic composition of the cecal flora was mainly bacteroidaceae and clostridia and did not change over a long period, and the floral composition became similar to that of CV rabbits. The fertility and weaning rates of the SPF rabbits were satisfactory for a SPF rabbit colony. In addition, these SPF colonies were free of more than one year rabbit-specific pathogens.

A novel in-frame deletion mutation in a case of lactate dehydrogenase (LD) H subunit deficiency showing an atypical LD isoenzyme pattern in serum and erythrocytes

OBJECTIVE

We report a case showing an atypical lactate dehydrogenase (LD) isoenzyme pattern involving deficiency only of LD-1 and LD-2 in serum and erythrocytes. LD activity in serum from this patient was extremely low, similar to complete LD-H deficiency, and also that in erythrocytes was low.

DESIGN

The DNA fragment containing exon 1 through 7 of the LD-H gene were amplified by PCR and directly sequenced. Total RNA was prepared from venous blood and the proportion of LD-H cDNA to total LD cDNA was semiquantified.

RESULTS

Genetic analysis by DNA sequencing detected a three base deletion (AAT) at codon 220 of exon 5, which caused a deletion of one asparagine. The present case did not show reduced LD-H expression at the mRNA level in whole blood. Residue 220 is involved in turning beta-J to alpha1-G and is not buried in the interior of the protein. The novel homozygous in-frame deletion mutation at codon 220 may cause a three-dimensional change of the subunit-binding domain.

Pulmonary embolectomy for acute massive pulmonary embolism under percutaneous cardiopulmonary support

Portable percutaneous cardiopulmonary support (PCPS) with heparin-coated circuits and a biopump was employed in a patient who had a massive pulmonary embolism with circulatory collapse after stripping of varicosities of the leg. Emergency pulmonary embolectomy was successfully performed. The main pulmonary incision was facilitated by cross-clamping of the main pulmonary arterial root. The bypass circuit was kept closed, and used with the normothermic beating heart without converting to conventional total cardiopulmonary bypass. Blood flow from the lung was removed by pump suction, stored in the reservoir, and intermittently returned to the venous circulation. Heparin was added to the circuits to keep the activated clotting time greater than 300 sec. In massive pulmonary embolism, PCPS is useful for preoperative, intraoperative, and postoperative support.

Features of spontaneous improvement in syringomyelia with low-situated cerebellar tonsils

We analysed four patients who showed spontaneous improvement among the 19 nonsurgically treated cases of syringomyelia with low-situated cerebellar tonsils who visited our outpatient clinic. MR images both before and after improvement were available for two of these patients; CT-myelography before improvement and MR images after improvement were used for two patients. Consequently, we were able to abstract several features from detailed and precise neurological and radiological evaluations of these patients. These features consisted of mild (rather than severe) disability, as well as three radiological features--a rounded shape of the lower edge of the cerebellar tonsils, a low tightness of the foramen magnum, an elevation of the tonsils during the course of the disease. Results of our radiological analyses were consistent with the theories proposed for the pathogenesis of syringomyelia in the light of the CSF flow around the foramen magnum. We propose that the features we have isolated are useful in determining treatment policies and prognoses of patients with syringomyelia, accompanied by low-situated cerebellar tonsils.

Features of spontaneous improvement in syringomyelia with low-situated cerebellar tonsils

We analysed six patients who showed spontaneous improvement among the 19 nonsurgically treated cases of syringomyelia with low-situated cerebellar tonsils who visited our outpatient clinic. MR images both before and after improvement were available for two of these patients; CT-myelography before improvement and MR images after improvement were used for two patients; and in the remaining two patients, MR images after improvement only were used. Consequently, we were able to abstract several features from detailed and precise neurological and radiological evaluations of these patients. These features consisted of mild (rather than severe) disability, as well as four radiological features--a rounded shape of the lower edge of the cerebellar tonsils, a low tightness of the foramen magnum, an elevation of the tonsils during the course of the disease. Results of our radiological analyses were consistent with the theories proposed for the pathogenesis of syringomyelia in the light of the CSF flow around the foramen magnum. We propose that the features we have isolated are useful in determining treatment policies and prognoses of patients with syringomyelia accompanied by low-situated cerebellar tonsils.

Novel anti-respiratory syncytial(RS) viral compounds: benzodithiin derivatives

Benzodithiin derivatives are highly potent and specific inhibitors of respiratory syncytial virus (RSV) replication in vitro. The most potent and selective congener of a benzodithiin derivative is 1,4-dihydro-2,3-benzodithiin(RD3-0028). According to the modified 3-(4,5-dimethylthiazole-2-yl) 2,5-diphenyl tetrazolium bromide (MTT) assay developed in our laboratories, this compound has a 50% effective concentration of 4.5 microM and a 50% cytotoxic concentration of 271.0 microM, which is superior to that of ribavirin. This compound also inhibits RSV strain subgroups A and B and clinical isolates. RD3-0028, however, does not inhibit the replication of influenza A virus, measles virus, herpes simplex virus types 1 and 2, or human cytomegalovirus. Two other benzodithiin derivatives [1,4-dihydro-6-methyl-2,3-benzodithiin (RD3-0270) and 1,4-dihydro-5-methyl-1-2,3-benzodithiin (RD3-0284)] also inhibit RSV replication at a selectivity index greater a factor of 20. These results suggest that the benzodithiin skeleton is an important structure for inhibitory activity against RSV replication.