Effect of adenosine triphosphate on human coronary circulation

We investigated in humans the effects of adenosine triphosphate (ATP), administered by intracoronary bolus (4-16 microg) or intravenous infusion (25-200 microg/kg/min), on coronary and systemic hemodynamics and electrocardiogram (ECG) variables. All patients had normal epicardial coronary arteries. The maximal coronary blood flow velocity (CBFV) was determined with intracoronary bolus of papaverine. A 12 microg bolus of ATP (n=12) caused maximal coronary hyperemia similar to that caused by papaverine. Intracoronary boluses caused a small brief decrease in arterial pressure but no significant changes in HR or ECG variables. Intravenous infusion of ATP at 150 microg/kg/min (n=15) caused a decrease in the coronary resistance index similar to that caused by papaverine, but the rate of increase in CBFV by ATP was smaller than that caused by papaverine. No patients had a significant change in ECG variables, but some patients (40%) had a serious decrease in arterial pressure. These studies suggest that maximal coronary vasodilation can be achieved safely with intracoronary ATP administration and that intravenous infusions at 150 microg/kg/min cause near-maximal coronary hyperemia in most patients.

[Pulmonary actinomycosis with "balls-in-a hole" appearance diagnosed by examination of bronchial lavage fluid]

A 49-year-old man was referred to our hospital because of abnormal chest X-ray findings. Chest X-ray films showed infiltrative opacities in the right lung, and histological findings of a transbronchial biopsy specimen showed non-specific inflammation. The patient was treated with Ofloxacin for one month. After the treatment, chest X-ray films showed that the infiltrative opacities in the right upper lobe had decreased, but that opacities in the right lower lobe had increased, with an air meniscus sign. A chest computed tomography scan at the same time revealed that the remaining opacities contained multiple mass-like lesions within a cavity in the right S6, appearing as "balls in a hole". One year after the first visit, the patient visited the hospital again because of cough and sputum. A chest X-ray film showed that the size of the cavity in the right lower lobe had increased. The histological findings from a fresh transbronchial biopsy specimen revealed a non-specific inflammation again; however, black clots obtained from bronchial lavage fluid after biopsy were histologically identified as sulfur granules, a classic pathological indication of actinomycosis. This confirmed the diagnosis of pulmonary actinomycosis. The patient was treated with penicillin, and the opacities in the right lower lobe subsided.

Panipenem-betamipron and decreases in serum valproic acid concentration

Serum concentrations of valproic acid (VPA) were reduced to 0% to 40% of the original levels by concomitant use with panipenem-betamipron (PAM-BP) in three patients. The serum VPA level began to decrease 2 days after the administration of PAPM-BP, and it began to increase within 24 hours of the last dose. The rapid change in the serum VPA level suggests the existence of unique and as yet unknown mechanisms of interaction between VPA and PAPM-BP. Epileptic seizures developed in two of the three patients during PAPM-BP use, which signaled the dangers of PAPM-BP administration to patients concomitantly administered VPA. PAPM-BP should not be used in patients administered VPA.

Drop episodes in Coffin-Lowry syndrome: exaggerated startle responses treated with clonazepam

A 16-year-old girl had fully manifested Coffin-Lowry syndrome and drop episodes. Her drop episodes were precipitated by sudden unexpected tactile or auditory stimuli associated with the electrostatic circumstances in her leg muscles immediately after the stimuli. Studies revealed that her drop episode symptom was an unusual type of startle response and that it may be associated with Coffin-Lowry syndrome.

Interstitial deletion of the long arm of chromosome 4 [del(4)(q21.22q23)] and a liver tumor

We report on a boy with proximal interstitial deletion of chromosome 4, del(4)(q21.22q23). The patient was born at term with a low birth weight, flat nasal bridge, micrognathia, wide-spaced nipples, clinodactyly of fifth fingers, overlapping fingers, post-axial polydactyly of the right foot, micropenis, hypospadias, a dermal sinus, and cardiac malformations. He developed psychomotor retardation, seizures, and a liver tumor with an increased serum alpha-fetoprotein level and rapid growth. The patient carried a deletion of chromosome 4 involving the 4q21-q22 region that was reported to form a unique syndrome. The absence of central nervous system overgrowth and the presence of a malignant liver tumor are unique to our patient, compared to others with the 4q21-q22 deletion syndrome. The clinical manifestations and relationship between the liver tumor and chromosomal anomaly are discussed.

Glycosylation of amphipathic lactoside primers with consequent inhibition of endogenous glycosphingolipid synthesis

The incubation of amphipathic lactosides with cultured cells was found to prime the glycosylation of lactosides whose oligosaccharide structures were exactly the same as those of glycosphingolipids produced by cells: B16 melanoma cells produced alpha2-3 sialylated lactosides; and PC12 cells, Galalpha1-4- and Galalpha1-3Galalpha1-4lactosides. Analysis of the cell-associated glycosylated products indicated that C16 series lactoside primers function 5-6 times more efficiently as acceptors than C12 series primers. The glycosylated lactosides were also secreted into the culture medium. Lactoside primers with longer hydrophobic chains hampered the release of glycosylated products from cells. The presence of an N-acyl chain in the lipophilic moiety of primers suppressed the secretion of glycosylated products. Owing to its overall availability, lactosides with the C12 alkyl chain were glycosylated 2-3 times more than C16 series lactosides and 1.4 times more than lactosides with the C12 acyl chain. C8-lactosides did not function as primers under the conditions of this study, but they were found to be the best acceptors for sialic acid transfer with the soluble enzyme fraction. The incubation of cells with 10 microM N-hexadecanoylaminoethyl-beta-O-lactoside caused a 30% decrease in endogenous GM3 of B16 cells and a 34% decrease in Gb3Cer synthesis of PC12 cells. The results of the present study demonstrate that lactoside primers serve as an efficient means to inhibit endogenous glycosphingolipids in studies to clarify glycosphingolipid functions.

[Radiofrequency catheter ablation therapy in elderly patients with supraventricular tachycardia]

138 patients with Wolf-Parkinson-White (WPW) syndrome (n = 96), atrioventricular nodal reentrant tachycardia (AVNRT; n = 27) and the other supraventricular tachycardia (n = 15), were divided into two groups, a control group (less than 65 years old; n = 108) and an elderly group (more than 66 years old; n = 30). We then estimated the success rate and safety of radiofrequency ablation for supraventricular tachycardia in elderly patients. For WPW syndrome, there were 76 (97%) successes and 9 (13%) recurrences in the control group (n = 78). In the elderly group of WPW patients, the number of successes was 18 (100%) and the number of recurrences one (63%). In 27 patients with AVNRT, the number of successes was 26 (96%) and there were no recurrences. In 15 patients with some other supraventricular tachycardia, there were 11 patients (73%) successes and one recurrence (11%). Major complications consisted of cardiac tamponade in 2 patients, dissecting aneurysm in one patient and cerebral embolism in one patients. All major complications occurred in patients with WPW syndrome. The cause of the complications, except the cerebral embolism was manipulation of the electrical or ablation catheter. Three of four patients with major complications belonged to the control group. It is possible that radiofrequency catheter ablation for supraventricular tachycardia in elderly patients is safe and highly effective. However, it is still invasive therapy. Ablation on a left accessory pathway by the transaortic valve approach especially needs meticulous care.

A DNA repair defect in a patient with ataxia, mental retardation, and short stature

A 12-year-old girl developed ataxia that gradually progressed. At age 18 the patient presented with mental retardation, cachectic dwarfism, microcephalus, and a progeroid appearance but no photosensitive skin lesions or deafness. On analysis of fibroblasts, unscheduled DNA synthesis was reduced to 50% of normal, but colony-forming ability after ultraviolet irradiation was normal. The symptoms and phenotype of the patient were distinguished from those in Cockayne syndrome and xeroderma pigmentosum. This case is interesting because the defect in DNA repair after ultraviolet irradiation was detected in a patient with neurologic disturbances but without photosensitive skin lesions.

Hypertrophic cardiomyopathy in congenital myotonic dystrophy

Involvement of the cardiac conduction system is a common clinical feature in myotonic dystrophy, whereas the association of primary myocardial abnormalities has rarely been reported. A patient with a severe form of congenital myotonic dystrophy who developed fatal left ventricular hypertrophy at 3 months of age and died at 2 years of age is reported. Serial ultrasonographic studies revealed progressive left ventricular hypertrophy accompanied by outflow obstruction of the left ventricle. Southern analysis for the myotonin kinase gene revealed a 5.8 kb expansion of CTG repeats in addition to a fragment of normal length. The degree of expansion was much greater than those of other reported patients with congenital myotonic dystrophy. These findings suggest that left ventricular hypertrophy represents an extreme level of myocardial damage in myotonic dystrophy and that this damage may be related to the larger size of the CTG repeats.

Structural characteristics of Koch's triangle in patients with atrioventricular node reentrant tachycardia

The aim of this study is to investigate whether patients with atrioventricular node reentrant tachycardia (AVNRT) present different structural characteristics of Koch's triangle from patients with atrioventricular (AV) reentrant tachycardia and other control patients. Fifty-eight patients with arrhythmia or chest pain underwent selective coronary sinus angiography so that the diameter of the coronary sinus could be measured. The patients with arrhythmia also underwent electrophysiological study and measurement of the height of Koch's triangle. Patients with AVNRT had large coronary sinus ostial diameters compared with patients with AV reentrant tachycardia and those with chest pain (13.6 +/- 2.2 mm vs. 10.6 +/- 2.7 mm [p < 0.005] and 10.0 +/- 2.1 mm [p < 0.002], respectively), while there were no differences in distal diameter. The ostial diameter in patients with dual AV node pathways but noninducible AVNRT (11.8 +/- 1.5 mm) tended to be smaller than that in patients with AVNRT. No differences in the height of Koch's triangle and electrophysiological characteristics, including AV node properties, were found among the study groups. In conclusion, an increased size of the coronary sinus ostium (the base of Koch's triangle) is a structural characteristic in patients with AVNRT and may be the substrate needed for the appearance of AVNRT.

Clinical and electroencephalographic findings in juvenile type DRPLA

We present five different types of dentatorubral-pallidoluysian atrophy in one Japanese family. Two siblings and their paternal uncle manifested the juvenile type dentatorubral-pallidoluysian atrophy, the siblings' father had the late-adult type, and another paternal uncle had the early-adult type. Gene analysis confirmed the diagnosis for the proband and her sibling. By following the clinical courses and electroencephalographic changes, we found that the types of epileptic seizures and the electroencephalograms of the juvenile dentatorubral-pallidoluysian atrophy patients changed as the illness progressed. The siblings exhibited different levels of clinical severity despite the similar deoxyribonucleic acid expansion detected in their lymphocytes.

Overexpression of the MEN/ELL protein, an RNA polymerase II elongation factor, results in transformation of Rat1 cells with dependence on the lysine-rich region

The MEN gene (also called ELL) encodes an RNA polymerase II elongation factor that has been implicated in t(11;19)(q23;p13.1) translocation in myeloid leukemias. The function of another elongation factor, elongin, is known to be inhibited by VHL tumor suppressor protein in vitro, suggesting the possible relationship of aberrant transcriptional elongation to oncogenesis. We overexpressed the MEN protein in Rat1 fibroblasts to evaluate its transforming activity. MEN-overexpressing cells acquired the capacity for anchorage-independent growth. In addition, the growth factor requirement was decreased in these cells. However, cells expressing a deletion mutant of MEN lacking the lysine-rich region did not exhibit such biological abilities. c-Fos protein expression and AP-1 activity were elevated in the MEN-expressing cells, which might be part of the mechanism responsible for the transformation. The c-fos mRNA, the expression of which is known to be regulated partly at the stage of transcriptional elongation, appeared earlier in the MEN-expressing cells than in cells transfected with an empty vector or the deletion mutant lacking the lysine-rich region after stimulation with epidermal growth factor. The RNA polymerase II elongation factor MEN may play an important role in the regulation of cell proliferation.

Vasomotility and nitric oxide bioactivity of the bridging segments of the left anterior descending coronary artery

We compared bridging and nonbridging coronary artery segments with respect to the vasoconstrictor effect of acetylcholine. Bridging segments were hypersensitive to the constrictor effect of acetylcholine, and results suggest that the effect of nitric oxide on the acetylcholine-stimulated condition is decreased, or that the smooth muscle sensitivity to acetylcholine is increased.

[Two cases of anti-neutrophil cytoplasmic antibody-negative generalized Wegener's granulomatosis with alveolar hemorrhage]

Anti-neutrophil cytoplasmic antibody (ANCA) is a distinct marker for Wegener's granulomatosis. We report two cases of ANCA-negative Wegener's granulomatosis. A 70-year-old woman (case 1) and a 27-year-old woman (case 2), who had sinus symptoms and renal disorders, were admitted to our hospital with alveolar hemorrhage. Wegener's granulomatosis was diagnosed on biopsy of the nasal mucosa. Case 1 responded well to the combination therapy with cyclophosphamide and prednisolone, while case 2 responded well to pulse therapy with methyl-prednisolone. These findings suggest that patients with ANCA-negative Wegener's granulomatosis may respond well to chemotherapy. This might lead to an improved prognosis in even severe cases, even though the prognosis of generalized Wegener's granulomatosis with alveolar hemorrhage is usually poor.

Dependency on atrial electrophysiological properties of appearance of paroxysmal atrial fibrillation in patients with Wolff-Parkinson-White syndrome: evidence from atrial vulnerability before and after radiofrequency catheter ablation and surgical cryoablation

The pathogenesis of paroxysmal atrial fibrillation in patients with Wolff-Parkinson-White syndrome and the effects of elimination of accessory pathways on the appearance of atrial fibrillation are still controversial. Fifty-four patients with Wolff-Parkinson-White syndrome were classified into three groups: a No AF group (n = 24), patients without paroxysmal atrial fibrillation; an RF-AF Group (n = 12), patients with paroxysmal atrial fibrillation whose accessory pathways were eliminated using radiofrequency catheter ablation; and a Cryo-AF Group (n = 18), patients with paroxysmal atrial fibrillation whose accessory pathways were eliminated with surgical cryoablation. The electrophysiological characteristics of each group were evaluated prior to and following the elimination of their accessory pathways. As indices of atrial vulnerability, the presence of fragmented atrial activity and repetitive atrial firing zones were assessed. Inducibility of atrial fibrillation was significantly reduced following ablation of accessory pathways in the Cryo-AF group (83.3%-5.6%, P < 0.0001), while it was unchanged in the RF-AF group (83.3%-75%). In preablation studies, the effective refractory periods of the atrium in the RF-AF group and the Cryo-AF group were significantly shorter compared with the No AF group (204 +/- 18 ms, 197 +/- 16 ms vs 246 +/- 44 ms, respectively, P < 0.0001). Following ablation, the effective refractory period for patients in the Cryo-AF group was significantly prolonged compared with before ablation (197 +/- 16 ms to 232 +/- 24 ms, P < 0.0001). As a result of this prolongation of the effective refractory period of the atrium, the fragmented atrial activity and repetitive atrial response zones narrowed following ablation in the Cryo-AF group, but not in the RF-AF group. Therefore, the pathogenesis of atrial fibrillation in patients with Wolff-Parkinson-White syndrome may depend on the refractory period of the atrium rather than on the presence of accessory pathways.

Short-term and long-term effects of low-density lipoprotein (LDL) apheresis on restenosis after percutaneous transluminal coronary angioplasty (PTCA): is lowering Lp(a) by LDL apheresis effective on restenosis after PTCA?

It has been reported that serum lipoprotein(a) (Lp[a]) levels in patients with restenosis after percutaneous transluminal coronary angioplasty (PTCA) were significantly higher than in patients without restenosis. In this study, we evaluated the preventive effect of LDL apheresis on restenosis after PTCA in patients with hypercholesterolemia. For 10 patients who had shown a serum cholesterol level of more than 220 mg/dl despite treatment with antihypercholesterolemic drugs, LDL apheresis was conducted every 2 weeks after a successful PTCA until restenosis could be checked. In 4 patients, LDL apheresis was conducted for 2 years. LDL apheresis significantly reduced serum cholesterol from 248 +/- 22 mg/dl to 135 +/- 26 mg/dl and Lp(a) from 42 +/- 34 mg/dl to 21 +/- 16 mg/dl. The average degree of stenosis in the 11 lesions undergoing PTCA was 92 +/- 6% before PTCA, 35 +/- 10% immediately after PTCA, and 38 +/- 19% at 3 to 4 months after PTCA. Restenosis was observed in only 1 lesion. In 4 patients who received LDL apheresis for 2 years, restenosis did not occur in any of the 4 lesions treated. We concluded that LDL apheresis was an efficacious therapy to prevent restenosis after PTCA in patients with hypercholesterolemia.

Increased cytosolic free Mg2+ and Ca2+ in platelets of patients with vasospastic angina

This study was designed to test the hypothesis that the cellular metabolism of Ca2+ and Mg2+, which is important in platelet function, is abnormal in the platelets of patients with vasospastic angina. Cytosolic free Mg2+ concentration ([Mg2+]i) and Ca2+ handling were determined in the platelets of 24 patients with vasospastic angina and 24 control subjects by use of mag-fura 2 and fura 2. Platelet aggregation was also examined. Basal [Mg2+]i and cytosolic free Ca2+ concentration ([Ca2+]i) in platelets were significantly higher in patients with vasospastic angina than in control subjects. The amplitude of the [Ca2+]i transient induced by thrombin (0.03-1.0 U/ml) was significantly increased in the presence, but not in the absence, of extracellular Ca2+ in patients with vasospastic angina, as compared with controls. Therefore, the influx of Ca2+ across the plasma membrane may be accelerated in vasospastic angina. Thrombin (0.1-1.0 U/ml)-induced maximum aggregation response was significantly greater in patients with vasospastic angina than in controls. Results suggest that increased [Mg2+]i and altered Ca2+ handling by platelets may be associated with coronary vasospasm.

Nucleotide sequencing analysis of the 146-kilobase segment around the IkBL and MICA genes at the centromeric end of the HLA class I region

To elucidate the complete gene structure and to identify new genes involved in the development of HLA class I antigen-associated diseases in the class I region of the human major histocompatibility complex on chromosome 6, a YAC clone (745D12) covering the 146-kb segment around the IkBL and MICA loci was isolated from a YAC library constructed from the B-cell line, BOLETH. A physical map of this region was constructed by isolation of overlapping cosmid clones derived from 745D12. Of these, five contiguous cosmids were chosen for DNA sequencing by the shotgun strategy to give a single contig of 146,601 bp from 2.8 kb telomeric of the IkBL gene to exon 6 of MICA. This region was confirmed to contain five known genes, IkBL, BAT1, MICB, P5-1, and HLA-X (class I fragment), from centromere to telomere, and their exon-intron organizations were determined. The 3.8-1 homologue gene (3.8-1-hom) showing 99.7% identity with the 3.8-1 cDNA clone, which was originally isolated using the 3.8-kb EcoRI fragment between the HLA-54/H and the HLA-G genes, was detected between MICA and MICB and was suggested to represent the cognate 3.8-1 genomic sequence from which the cDNA clone was derived. No evidence for the presence of expressed new genes could be obtained in this region by homology and EST searches or coding and exon prediction analyses. One TA microsatellite repeat spanning 2545 bases with as many as 913 repetitions was found on the centromeric side of the MICA gene and was indicated to be a potential hot spot for genetic recombination. The two segments of approximately 35 kb upstream of the MICA and MICB genes showed high sequence homology (about 85%) to each other, suggesting that segmental genome duplication including the MICA and MICB genes must have occurred during the evolution of the human MHC.

Effects of dichloroacetate in three patients with MELAS

We present the clinical and laboratory effects of dichloroacetate (DCA) in three children with mitochondrial myopathy, encephalopathy, lactic acidosis, and strokelike episodes (MELAS) who had not responded to other medications. Administration of DCA lowered the elevated levels of lactate and pyruvate in the serum and CSF. DCA ameliorated abdominal pain, headache, and strokelike episodes, and improved cognitive function and fatigability in the three patients during the study period. Some transient liver dysfunction, hypocalcemia, and peripheral neuropathy were observed. The use of DCA in MELAS merits further study.

A novel muscle spindle containing muscle fibres devoid of sensory innervation in the posterior cricoarytenoid muscle of the normal adult guinea pig

A novel muscle spindle composed of five thin intrafusal muscle fibres and four thick muscle fibres was encountered in the posterior cricoarytenoid muscle of the normal adult guinea pig. Four intrafusal muscle fibres of the five were innervated by the annulospiral type of sensory ending, but lacked a distinct aggregation of equatorial nuclei such as bags and chains. On the other hand, one intrafusal fibre and four thick fibres between the layers of the spindle capsule absolutely lacked sensory innervation and were almost similar in the fine structural features to neighbouring extrafusal fibres. These fibres are considered to fail to receive the sensory innervation in an early stage of development, and to retain an undifferentiated feature of intrafusal fibre in the intracapsular space into adulthood or to follow the course of extrafusal differentiation between the layers of the spindle capsule. It is suggested therefore that this muscle spindle may be primitive.

c-Cbl is tyrosine-phosphorylated by interleukin-4 and enhances mitogenic and survival signals of interleukin-4 receptor by linking with the phosphatidylinositol 3'-kinase pathway

Interleukin-4 (IL-4) is a cytokine that induces both proliferation and differentiation and suppresses apoptosis of B cells. Although IL-4 has been shown to activate the phosphatidylinositol 3' (PI3)-kinase pathway, the role of PI3 kinase in the IL-4 receptor (IL-4R) signaling remains unclear. In this study, we demonstrated that c-Cbl proto-oncogene product is inducibly phosphorylated on tyrosine residues and is associated with the p85 subunit of PI3-kinase by IL-4 stimulation. Overexpression of c-Cbl enhances the PI3-kinase activity and, at the same time, mitogenic activity and survival of cells in the presence of IL-4. However, these effects of c-Cbl were abolished by wortmannin, a specific inhibitor for the PI3 kinase pathway, or by a point mutation at tyrosine 731 of c-Cbl, which is a major binding site for p85. These results indicate that c-Cbl plays a role in linking IL-4R with the PI3 kinase pathway and thus enhancing the mitogenic and survival signals.

Production of reactive oxygen species and release of L-glutamate during superoxide anion-induced cell death of cerebellar granule neurons

Enhanced production of superoxide anion (O2-) is considered to play a pivotal role in the pathogenesis of CNS neurons. Here, we report that O2- generated by xanthine (XA) + xanthine oxidase (XO) triggered cell death associated with nuclear condensation and DNA fragmentation in cerebellar granule neuron. XA + XO induced significant increases in amounts of intracellular reactive oxygen species (ROS) before initiating loss of cell viability, as determined by measurement of 6-carboxy-2',7'-dichlorodihydrofluorescein diacetate, di(acetoxymethyl ester) (C-DCDHF-DA) for O2- and other ROS and hydroethidine (HEt) specifically for O2- by using fluorescence microscopy and flow cytometry. Catalase, but not superoxide dismutase (SOD), significantly protected granule neurons from the XA + XO-induced cell death. Catalase effectively reduced C-DCDHF-DA but not HEt fluorescence, whereas SOD reduced HEt but not C-DCDHF-DA fluorescence, indicating that HEt and C-DCDHF-DA fluorescence correlated with O2- and hydrogen peroxide, respectively. The NMDA antagonist MK-801 prevented the death. XA + XO induced an increase in L-glutamate release from cerebellar granule neurons. These results indicate that elevation of O2- induces cell death associated with increasing ROS production in cerebellar granule neurons and that XA + XO enhanced release of L-glutamate.