Missense mutation of the beta-cardiac myosin heavy-chain gene in hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy occurs as an autosomal dominant familial disorder or as a sporadic disease without familial involvement. We describe a missense mutation of the beta-cardiac myosin heavy chain (MHC) gene, a G to T transversion (741 Gly-->Trp) identified by direct sequencing of exon 20 in four individuals affected with familial hypertrophic cardiomyopathy. Three individuals with sporadic hypertrophic cardiomyopathy, whose parents are clinically and genetically unaffected, had sequence variations of exon 34 of the alpha-cardiac MHC gene (a C to T transversion, 1658 Asp-->Asp, resulting in FokI site polymorphism), of intron 33 of the alpha-cardiac MHC gene (a G to A and an A to T transversion), and also of intron 14 of the beta-cardiac MHC gene (a C to T transversion in a patient with Noonan syndrome). Including our case, 30 missense mutations of the beta-cardiac MHC gene in 49 families have been reported thus far worldwide. Almost all are located in the region of the gene coding for the globular head of the molecule, and only one mutation was found in both Caucasian and Japanese families. Missense mutations of the beta-cardiac MHC gene in hypertrophic cardiomyopathy may therefore differ according to race.

Non-radioactive DNA diagnosis for the fragile X syndrome in mentally retarded Japanese males

A rapid screening test was developed to detect CGG repeat expansion of the FMR-1 gene causing the fragile X syndrome by a non-radioisotope PCR technique. A biotin-labeled primer was initially used and the biotin-labeled PCR product was detected by means of chemiluminescence. The normal PCR product of around 300 bp was not created in the abnormal FMR-1 gene sample with this method. Four positive samples were found among those from 226 mentally retarded males, but the CGG repeat expansion was shown on Southern blot analysis in only one sample. To eliminate false-positive samples, a hybridization method involving a biotin-labeled (CGG)s oligonucleotide was developed for the PCR product and the CGG repeat expansion could be detected. Finally, 256 mentally retarded males in Japan were examined and only 2 abnormal samples were detected. The prevalence of this abnormality was less than 1%, which is relatively lower than those reported previously.

Accelerated desensitization of nicotinic receptor channels and its dependence on extracellular calcium in isolated skeletal muscles of streptozotocin-diabetic mice

1. To elucidate the influence of the diabetic state on desensitization of nicotinic acetylcholine (ACh) receptor channels, we investigated the time course of the decrease in amplitude of ACh potentials elicited by iontophoretic application to isolated diaphragm muscle of streptozotocin-diabetic mice. We also investigated time- and extracellular Ca(2+)-dependent changes in the channel opening frequency of ACh-activated channel currents and the involvement of protein kinases by use of the cell-attached patch clamp technique in single skeletal muscle cells. 2. When ACh potentials were evoked at 10 Hz, the decline in trains of ACh potentials was accelerated in the diabetic state. 3. The time-dependent decrease in the channel opening frequency of diabetic muscle cells was greatly accelerated compared with normal cells in 2.5 mM Ca2+ medium. 4. This accelerated decrease in channel opening frequency was restored by pretreatment with a protein kinase C inhibitor, staurosporine (10 nM) but neither a protein kinase A inhibitor, H-89 (3 microM) nor a calmodulin kinase II inhibitor, KN-62 (5 microM) were able to restore the fall in opening frequency. 5. These results demonstrate that in the diabetic state the desensitization of nicotinic ACh receptor channels may be greatly accelerated by activating protein kinase C, which is caused by an increase in the amount of available intracellular Ca2+.

Species-specific PCR detection of malaria parasites by microtiter plate hybridization: clinical study with malaria patients

A simple and convenient PCR method that amplifies the 18S rRNA genes has been developed for the purpose of detecting and differentiating four species causing malaria in humans. The advantage of the assay is that the biotinylated PCR product is visualized following hybridization with specific probes which are immobilized on plate wells (microtiter plate hybridization). This method has been previously evaluated in a field study and was found to be sensitive and specific for the detection of Plasmodium falciparum and Plasmodium vivax. In the current study, the microtiter plate hybridization PCR method was evaluated by using blood specimens from malaria patients. All of 36 cases of falciparum malaria, 26 of 27 cases of vivax malaria, all of 11 cases of ovale malaria, and 2 cases of malariae malaria were diagnosed species specifically by the PCR method. There were four smear-negative, PCR-positive cases that seemed to correspond to the convalescent stage of malaria. In contrast, 30 cases for which the diagnosis of malaria has been excluded on the basis of microscopy and clinical courses showed negative PCR results. By comparing parasite densities and PCR results following antimalarial treatment of some patients, it was revealed that the PCR results largely paralleled the parasite densities and that PCR could detect as few as 10 parasites per microliter of blood. We conclude that this PCR method is highly sensitive and specific for the detection of all four parasite species and can serve as a useful supplement to microscopy for the clinical management of malaria.

[Pulmonary malignant fibrous histiocytoma treated with cisplatin plus etoposide followed by surgery]

A 47-year-old woman was admitted to our hospital with a mass shadow in the upper lobe of the right lung. Undifferentiated carcinoma was diagnosed after transbronchial biopsy. Combination chemotherapy consisting of cisplatin and etoposide was given. After two cycles of chemotherapy, partial response was obtained, and surgery was done because there was no evidence of lymph node metastasis or distant metastasis. After successful surgery, malignant fibrous histiocytoma was diagnosed because histological examination revealed the typical storiform pattern and most tumor cells showed positive cytoplasmic staining for alpha 1-antitrypsin, alpha 1-antichymotrypsin, and CD68. No evidence of another primary lesion was found, so this tumor was thought to be a pulmonary malignant fibrous histiocytoma. Cisplatin and etoposide have synergistic effect in vivo, and this combination is widely used as a standard regimen for small cell lung cancer and other malignancies. It might also be effective against pulmonary malignant fibrous histiocytoma.

The structure-activity relationship between synthetic butylidenephthalide derivatives regarding the competence and progression of inhibition in primary cultures proliferation of mouse aorta smooth muscle cells

The inhibitory effects of synthetic butylidenephthalide (BP) derivatives on 10% fetal bovine serum-stimulated proliferation were assayed by measuring the proliferative cell number at an interval of 12 h in primary cultures of mouse aorta smooth muscle cells (SMC). Their potencies for the anti-proliferation effect were in the order BP-42 (4,5-dihydroxy BP) > BP-92 (4,5-dihydroxy butylphthalide) > BP-97 (6,7-dihydroxy-3-(3-bromo-1-octenyl)-phthalide) > BP-82 (6,7-dihydroxy BP) > BP-86 (5,6-dihydroxy BP) > BP-87 (4,5,6-trihydroxy BP) > BP-85 (4,7-dihydroxy BP) > BP-84 (5,7-dihydroxy BP) > BP-4C3 (4-methoxy propylphthalide) > BP-7 (4-hydroxy BP) > BP-40 (4,5-dimethoxy butylphthalide) > BP-5C3 (4-hydroxy propylphthalide). We divided these anti-proliferative effects into anti-competence and anti-progression effects by using a convenient assay. BP-42 had the greatest potency in used phthalides for competence inhibition of the SMC proliferation. BP-92 had small potency for competence inhibition. BP-97 had greater potency for competence inhibition than BP-82. These results demonstrated that the anti-proliferative effect of BP-42 was greatest in used phthalides in primary cultures of vascular SMC. The 4,5-dihydroxy group and 3-butylidene or 3-(3-bromo-1-octenyl) group in these synthetic BP derivatives contributed to the anti-competence effect on SMC. BP-42 may become a prototype of an anti-atherosclerotic drug.

Pitfall of superselective catheterization by 3F catheter for spinal arteriovenous malformation

We experienced a case of subarachnoid rupture of a spinal arteriovenous malformation (AVM) following the injection of contrast medium through a 3F wedged catheter inserted into the feeding artery. If blood does not come through the catheter in the feeding artery of a spinal AVM, not even test injection should be done, to avoid rupture of the spinal AVM.

Immunohistochemical localization of neuronal nicotinic receptor subtypes at the pre- and postjunctional sites in mouse diaphragm muscle

The existence of neuronal nicotinic acetylcholine receptor (nAChR) subunits was investigated in the cryostat sections of mouse diaphragm muscles using the indirect immunofluorescence technique. The specific immunolabelings with monoclonal antibodies (mAbs) to beta 2 and to alpha 8 subunits of neuronal nAChR were observed at the endplate determined by labeling with a fluorescent dye (BODIPY)-conjugated alpha-bungarotoxin. The immunoreactivity of mAb to the alpha 3 subunit of neuronal nAChR was detected on the motor nerve fibers including the nerve terminals. These results provide evidence that the subtypes of postsynaptic nAChR, recognized by the anti-beta 2 and/or anti-alpha 8 mAbs, and the presynaptic nAChR recognized by the anti-alpha 3 mAb, are present at the neuromuscular junction, in addition to the classical muscle nAChR.

Role of cyclic nucleotides in store-mediated external Ca2+ entry in human platelets

This study explores the role of cyclic nucleotides (i.e. cyclic AMP and cyclic GMP) in store-regulated external Ca2+ entry in human platelets. To stimulate store-regulated external Ca2+ entry, thapsigargin was used to deplete Ca2+ from the dense tubules, and sodium nitroprusside and iloprost respectively were used to stimulate endogenous cyclic GMP and cyclic AMP formation. Pretreatment with sodium nitroprusside and iloprost (a) attenuated the thapsigargin-evoked external Ca2+ entry and (b) reduced the rate of Ca2+ release from the dense tubules. The effects on external Ca2+ entry and Ca2+ release from the dense tubules were exerted independently and were apparently mediated through activation of the respective cyclic nucleotide-dependent protein kinases. Both sodium nitroprusside and iloprost reduced tyrosine kinase phosphorylation of a number of proteins, particularly a 72 kDa protein band. Both agents also attenuated the thapsigargin-evoked tyrosine kinase phosphorylation of the 72 kDa band. Intracellular Ca2+ depletion resulted in a reduction in tyrosine kinase-mediated phosphorylation of a number of protein bands, including the 72 kDa band and the further attenuation of thapsigargin-mediated tyrosine phosphorylation of this band. The effects of the cyclic nucleotides on cellular Ca2+ homoeostasis in thapsigargin-treated platelets were not exerted via acceleration of Ca2+ extrusion or Ca2+ sequestration into the mitochondria. We conclude that cyclic nucleotides participate in store-regulated control of external Ca2+ entry by slowing down the rate of external Ca2+ entry and Ca2+ release from intracellular Ca2+ stores. These effects are apparently mediated via cyclic nucleotide-dependent protein kinases and the attenuation of protein phosphorylation by tyrosine kinases.

Effect of antiepileptic drugs on thyroid function

Chronic treatment with antiepileptic drugs (AED) is known to reduce serum thyroid hormone levels. Serum thyrotropin (TSH) level is unchanged despite low thyroxine (T4) level. We studied serum tri-iodothyronine (T3), T4 and TSH in 30 epileptic patients prior to discontinuation and 2, 4, 8 and 16 weeks after AED discontinuation. One AED was discontinued in each patient. Serum T3 levels were reduced consistently after AED discontinuation. Serum T4 and rT3 levels were increased, but not persistently. Serum TSH levels were unchanged. Our results suggest that during AED treatment serum T3 level was increased. This could be an increased conversion of T4 to T3. An acceleration of thyroid hormones degradation by enzyme induction is physiologically balanced by an increased conversion of T4 to T3.

[Eight cases of infection caused by the Streptococcus milleri group--significance of serum antibody titer and a comparative investigation of the backgrounds and factors of infections caused by Streptococcus milleri and Streptococcus pneumoniae]

Eight cases of infection caused by Streptococcus milleri were studied clinically, and a comparative study was made of the backgrounds and factors influencing the development of infectious diseases caused by Streptococcus milleri and Streptococcus pneumoniae. The patients (six males and two females) with infectious diseases caused by Streptococcus milleri ranged in age from 21 to 81 years old with an average age of 62.0 years. The infectious diseases encountered among the patients were pyothorax in three patients, and in one patient each pyothorax and lung abscess, pleurisy, a secondary infection of pulmonary emphysema, skin infection related to a tracheostomy, a subdural abscess and a brain abscess, respectively. Six out of the eight cases had infections which formed pus. An underlying disease existed in seven cases, and, in five of these seven cases, it influenced the general condition of these patients. Six serum antibody titers for the S. milleri groups were examined in the First Department of Internal Medicine, University of the Ryukyus. Three cases for S. anginosus, two cases for S. intermedius, and one case for S. constellatus showed high titers of X1024 or X2048. Therefore, the examination of the serum antibody titer seems useful for the diagnosis of infections caused by the S. milleri group. We also carried out a comparative investigation of the backgrounds and factors of infectious diseases caused by S. milleri and S. pneumoniae. There are more underlying diseases in infections caused by S. milleri than in those caused by S. pneumoniae. There were more smokers among the patients with infections caused by S. milleri than among those with S. pneumonia infections.(ABSTRACT TRUNCATED AT 250 WORDS)

[Detection of the exoskeleton of Sarcoptes scabiei in histological sections using Fungiflora Y]

Fungiflora Y was applied to a deparaffinized section of a biopsied skin with scabies, a section of a brain infected with Cysticercus cellulosae, a section of a lung infected with Pneumocystis carinii and a section of a cockroach. The exoskeleton of the mite and the cockroach were stained with Fungiflora Y and were visualized as a greenish-blue fluorescence under incident illumination with ultraviolet light, whereas the Cysticercus cellulosae and the Pneumocystis carinii were not visualized at all. Fungiflora Y, which has been reported to stain fungi, is likely to detect arthropods exoskeleton in histological sections.

Antibody responses raised against a conformational V3 loop peptide of HIV-1

The amino acid sequence of the principal neutralizing determinant (PND) of 224 cases of human immunodeficiency virus type 1 (HIV-1) was determined and the most frequently occurring sequence was used as a peptide antigen for studying virus-specific antibody responses. In our present study, a linear peptide of the most frequent PND was first synthesized and then oxidized to create a disulfide-bridged loop conformation. Then, in order to construct a macromolecular structure for the purpose of increasing antigenicity, the synthetic peptide was conjugated to a core peptide. We compared the immunogenicity of the disulfide-bridged loop PND peptide antigen (AG4) and the linear PND peptide antigen (AG5). After immunizing rabbits 5 and 6 times with both peptides, the results obtained using ELISA revealed that AG4 (conformational-loop type) was more capable of inducing a high titer of antigen-specific antibodies than was AG5 (linear type). Despite an amino acid sequence homology of 72%, a 1:8 dilution of serum raised against AG4 inhibited 81.9% of HIV-1IIIB-mediated cell fusion, suggesting that conformational V3 loop peptide is able to elicit an antibody response which is strongly HIV-1-specific.

The natural history of untreated anterior cruciate tears in recreational athletes

A followup study was performed to elucidate the natural course of acutely torn anterior cruciate ligaments in recreational athletes. Fifty-six consecutive patients had arthroscopy within 2 weeks of their initial injuries; however, no surgery was done on the torn anterior cruciate ligament. Twenty anterior cruciate ligament and medial collateral ligament combined ruptures occurred. Patient ages ranged from 14 to 50 years old (mean, 28.9 years). Followup periods ranged from 2 to 10 years (mean, 5 years 6 months). Through examination with the KT-1000 arthrometer, side-to-side differences of anterior translation of the tibia of > or = 3 mm in 72% patients at reexamination were seen. Eight of 46 patients had mild osteoarthritic changes of Grade 1 visible on radiographs, but only 1 patient reported knee trouble. Nine patients had repeat injuries, 3 of whom had late reconstructions and 4 late meniscectomies. Functional scores averaged 95 +/- 6.5 points. Activity scores averaged 4.8 +/- 1.6 points. Operative management for the medial structure did not improve the stability better than nonoperative management. Anterior translation and functional scores of patients with medial meniscectomies showed significant differences from those of other patients. Anterior cruciate ligament reconstruction for recreational athletes should be considered when the patients have reparable meniscal tears, and meniscal repairs should be performed simultaneously.

[MALT lymphoma of large intestine as multiple large polypoid lesions]

We report a case of mucosa associated lymphoid tissue (MALT) lymphoma in the large intestine in a 38-year-old Japanese female. She developed a dull pain in the right lower abdomen and was found to have ileocecal intussusception. The terminal ileum, cecum and ascending colon were resected. Macroscopically, multiple polypoid lesions were found. Although some authors reported that MALT lymphoma of the colon tend to be solitary, the present case showed seven lesions. Two of the polypoid lesions in the present case were marked large. No such large polypoid MALT lymphoma has been described to our knowledge. A histological and immunohistochemical study revealed those seven lesions to be low grade B cell lymphomas of MALT type.

The LIM class homeobox gene lim5: implied role in CNS patterning in Xenopus and zebrafish

LIM homeobox genes are characterized by encoding proteins in which two cysteine-rich LIM domains are associated with a homeodomain. We report the isolation of a gene, named Xlim-5 in Xenopus and lim5 in the zebrafish, that is highly similar in sequence but quite distinct in expression pattern from the previously described Xlim-1/lim1 gene. In both species studied the lim5 gene is expressed in the entire ectoderm in the early gastrula embryo. The Xlim-5 gene is activated in a cell autonomous manner in ectodermal cells, and this activation is suppressed by the mesoderm inducer activin. During neurulation, expression of the lim5 gene in both the frog and fish embryo is rapidly restricted to an anterior region in the developing neural plate/keel. In the 2-day Xenopus and 24-hr zebrafish embryo, this region becomes more sharply defined, forming a strongly lim5-expressing domain in the diencephalon anterior to the midbrain-forebrain boundary. In addition, regions of less intense lim5 expression are seen in the zebrafish embryo in parts of the telencephalon, in the anterior diencephalon coincident with the postoptic commissure, and in restricted regions of the midbrain, hindbrain, and spinal cord. Expression in ventral forebrain is abolished from the 5-somite stage onward in cyclops mutant fish. These results imply a role for lim5 in the patterning of the nervous system, in particular in the early specification of the diencephalon.

Enhancement of resistance to bacterial infection in mice by vitamin B2

We found that the intramuscular injection of vitamin B2 enhanced host resistance to E. coli infection in a dose-dependent manner (6.25 mg/kg-100 mg/kg). Furthermore, VB2 exhibited the protective activity against Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus aureus, and Actinobacillus pleuropneumoniae. The mechanism of action of VB2 for enhancing resistance in mice may be, at least in part, its ability to stimulate the multiplication of neutrophils and monocytes, and to activate macrophages.

Role of basal ganglia in behavioral learning

Recent studies on single neuron activity revealed that activities of many basal ganglia neurons are dependent upon the behavioral context. This may give us a reason why observed movement-related activity in the basal ganglia occurred late in relation to prime mover muscle activity. Early onset activity of primate putamen neurons was reported in a study in which animals were required to make a performance of sequential limb movements. This suggests the participation of basal ganglia in the initiation of movement in a behavioral context-dependent manner. The context-dependent activity in the basal ganglia has been shown to be acquired through learning. For instance, midbrain dopamine neurons respond to external sensory stimuli or reward only during early stages of learning motor tasks. Striate neurons acquire task-related activity through learning and the acquired activity almost disappears after selective lesions of nigrostriatal dopamine. In this article, a hypothetical scheme of basal ganglia functioning in behavioral learning is presented. Limbic input conveys information related to 'reinforcement' or 'incentive' either directly to the striatum or indirectly through nigrostriatal dopamine system, and it contributes to the acquisition and expression of learned activity in the striatum. The expression of learned striatal activity would contribute to the initiation of learned motor behavior.

Effect of selenium on malignant tumor cells of brain

Some reports have demonstrated that selenium can inhibit tumorigenesis in some tissues of animal. However, little is known about the inhibitory effect on malignant tumor cells of brain. The purpose of our study was to determine the biological effect of selenium on growth of rat glioma and human glioblastoma cell lines. Cell lines C6 and A172 were obtained from Japanese Cancer Research Resources Bank, Tokyo, Japan (JCRB). Cells were cultured in Dulbecco's Modified Eagle's Medium (DMEM) supplemented with 10% fetal calf serum at 37 degrees C in a humidified atmosphere of air and 5% CO2. Antiproliferative effects of selenium were evaluated using growth rate assay quantifying cell number by MTT assay. An antiproliferative effect of selenium was found in two cell lines, which was more effective on human A172 glioblastoma and less effective on rat C6 glioma.

Association between elevated plasma granulocyte colony-stimulating factor and the degree of surgical stress in patients undergoing gastrointestinal surgery

To characterize the changes in perioperative plasma granulocyte colony-stimulating factor (G-CSF) and analyze the effect of surgical stress on its kinetics, 41 patients undergoing gastrointestinal surgery with varying degrees of surgical stress were examined. The plasma levels of G-CSF significantly increased immediately after the operation, probably in response to surgical injury. This elevation was much higher in the 15 esophagectomy patients, at 883 +/- 300 pg/ml on postoperative day (POD) O, than in the 14 gastrectomy patients, with a value of 233 +/- 151 on POD O, (P < 0.01) or in the 12 cholecystectomy patients, with a value of 64 +/- 41 on POD 1 (P < 0.01). These findings led us to conclude that G-CSF levels increase significantly in the immediate postoperative period and are most likely associated with the degree of surgical stress. In addition, we studied the priming effect of G-CSF on polymorphonuclear leukocytes (PMNs). G-CSF enhanced PMN superoxide anion (O2-) production and luminol-dependent chemiluminescence (CL) induced by opsonized zymosan in a dose-dependent manner. A significant enhancement was seen in the G-CSF level (1 ng/ml) which was almost the same as the maximum G-CSF level in the esophagectomy patients. Furthermore, postoperative PMN activation occurred after the elevation of plasma G-CSF. Thus, we propose that elevated G-CSF may act as one of the mediators which activate PMN function postoperatively.