Repeated haemorrhages in peripheral nerve sheath tumours of the salivary glands after minor injury.

Repeated haemorrhages in peripheral nerve sheath tumours of the salivary glands are rare. We report the case of a patient with neurofibromatosis type 1 who had two episodes of massive haemorrhage in his right parotid gland the day after a minor injury. Oral and maxillofacial surgeons should be aware that vasculopathy may occur in patients with these tumours.

ITPKC and CASP3 polymorphisms and risks for IVIG unresponsiveness and coronary artery lesion formation in Kawasaki disease.

Functional single-nucleotide polymorphisms (SNPs) in inositol 1,4,5-trisphosphate 3-kinase C (ITPKC) (rs28493229) and caspase-3 (CASP3) (rs113420705; formerly rs72689236) are associated with susceptibility to Kawasaki's disease (KD). To evaluate the involvement of these 2 SNPs in the risk for intravenous immunoglobulin (IVIG) unresponsiveness, we investigated 204 Japanese KD patients who received a single IVIG dose of 2 g kg(-1) (n=70) or 1 g kg(-1) daily for 2 days (n=134). The susceptibility allele of both SNPs showed a trend of overrepresentation in IVIG non-responders and, in combined analysis of these SNPs, patients with at least 1 susceptible allele at both loci had a higher risk for IVIG unresponsiveness (P=0.0014). In 335 prospectively collected KD patients who were treated with IVIG (2 g kg(-1)), this 2-locus model showed a more significant association with resistance to initial and additional IVIG (P=0.011) compared with individual SNPs. We observed a significant association when all KD patients with coronary artery lesions were analyzed with the 2-locus model (P=0.0031). Our findings strongly suggest the existence of genetic factors affecting patients' responses to treatment and the risk for cardiac complications, and provide clues toward understanding the pathophysiology of KD inflammation.

Autonomic imbalance induced breakdown of long-range dependence in healthy heart rate.

OBJECTIVES: The investigation of the relation between the long-range correlation property of heart rate and autonomic balance. METHODS: An investigation of the fractal scaling properties of heart rate variability was carried out by using detrended fluctuation analysis (DFA). Eleven healthy subjects were examined for two consecutive days, which included usual daily activity, strenuous prolonged experimental exercise, and sleep. We also considered two patient groups with autonomic dysfunction characterized by selective sympathetic and parasympathetic dominance. RESULTS: Robust long-range dependence in heart rate is observed only in the state of usual daily activity, characterized by normal heart rate typical of balanced autonomic sympathetic and parasympathetic regulation. This confirms the previously postulated behavioral independence of heart rate regulation, but reveals that the occurrence of 1/f, long-range dependence is restricted to only the state of autonomic balance. Both the sympathetic dominant high heart rate state, realized during strenuous experimental exercise, and the parasympathetic dominant low heart rate state, prevalent in (deep) sleep, are characterized by uncorrelated, near white-noise-like scaling, lacking long-range dependence. CONCLUSION: Remarkably, the breakdown of the long-range correlations observed in healthy heart rate in the states of sympathetic and parasympathetic dominance is in stark contrast to the increased correlations which have previously been observed in neurogenic parasympathetic and sympathetic dominance in patients suffering from primary autonomic failure and congestive heart failure, respectively. Our findings further reveal the diagnostic capabilities of heart rate dynamics, by differentiating physiological healthy states from pathology.

Amyloid beta inhibits ectodomain shedding of N-cadherin via down-regulation of cell-surface NMDA receptor.

Dysfunction in the synapse is recognized as an early and the primary pathological process in Alzheimer's disease (AD). N-cadherin, an essential adhesion molecule for excitatory synaptic contact, forms a complex with presenilin 1 (PS1) and beta-catenin in the synaptic membrane. N-cadherin is sequentially cleaved by ADAM10 and PS1/gamma-secretase, producing a cytoplasmic fragment, N-cadherin C-terminal fragment (Ncad/CTF2) after NMDA receptor stimulation [Marambaud P, Wen PH, Dutt A, Shioi J, Takashima A, Siman R, Robakis NK (2003) A CBP binding transcriptional repressor produced by the PS1/epsilon-cleavage of N-cadherin is inhibited by PS1 FAD mutations. Cell 114:635-645; Reiss K, Maretzky T, Ludwig A, Tousseyn T, de Strooper B, Hartmann D, Saftig P (2005) ADAM10 cleavage of N-cadherin and regulation of cell-cell adhesion and beta-catenin nuclear signalling. EMBO J 24:1762]. Ncad/CTF2 translocates to the nucleus together with beta-catenin to enhance beta-catenin nuclear signaling [Uemura K, Kihara T, Kuzuya A, Okawa K, Nishimoto T, Bito H, Ninomiya H, Sugimoto H, Kinoshita A, Shimohama S (2006a) Activity-dependent regulation of beta-catenin via epsilon-cleavage of N-cadherin. Biochem Biophys Res Commun 345:951-958]. To examine whether an impairment of N-cadherin metabolism is involved in AD pathogenesis, we investigated the effect of amyloid beta peptide (Abeta) treatment on sequential N-cadherin cleavage. Here, we demonstrate that both synthetic and cell-derived Abeta species inhibit ectodomain shedding of mouse N-cadherin. Inhibition of N-cadherin cleavage by Abeta treatment was suggested to be mediated by the enhanced endocytosis of NMDA receptor, resulting in reduced turnover of N-cadherin. Since both N-cadherin and beta-catenin are essential for synaptic plasticity, impairment of N-cadherin cleavage caused by Abeta may underlie the synapse toxicity involved in AD pathogenesis.

Hydrodynamic flows around tablets in different pharmacopeial dissolution tests.

We investigated the hydrodynamic flows around tablets during several pharmacopeial dissolution tests: the rotating basket (RB), paddle (PD), flow-through cell (FT), and disintegration (DI) tests. The determination of hydrodynamic flow was based on the dissolution rate of United States Pharmacopeial salicylic acid nondisintegrating calibrators, and showed that, compared with the PD and RB methods, the FT method produced a lower hydrodynamic flow value whereas the DI method produced a higher value. The hydrodynamic flows during the PD and RB tests appeared to be similar at the same rotational speed, although the flow patterns around the tablet differed; with the RB method, homogeneous dissolution occurred from all surfaces of the tablet, while with the PD method, dissolution from the lower surface was slower. The use of a sinker seemed to enhance dissolution from the lower surface. Such differences in hydrodynamic flow could explain the apparently different dissolution behaviors of disintegrating prednisone and nondisintegrating acetaminophen tablets when assessed by the PD and RB methods. These differences in hydrodynamic flow between in vitro tests should be considered when choosing dissolution tests for studying in vitro/in vivo relationships and for quality control purposes.

The study of the applicability of content uniformity and weight variation test--the state of commercial tablets and capsules in Japan.

This study intends to determine the rational criteria (e.g., threshold value) for applying the weight variation test and to investigate the adequacy of the acceptance value for existing commercial products in Japan. The studied products were 489 lots (3 lots x 163 products) of compressed tablets (plain, film-coated, sugar-coated) and 42 lots (3 lots x 14 products) of hard capsules marketed in Japan. The individual drug content and the weight of 10 units in a lot were determined for each product and the acceptance values were calculated according to the Japanese Pharmacopoeia thirteenth edition (JP13) Content Uniformity Test (M=100.0, k=2.2). Product-specific intra-lot relative standard deviation of content (RSDD), weight (RSDW) and concentration (RSDC) were calculated by analysis of variance (ANOVA) using three lots of data per product. The RSDD and RSDC tended to increase with the decrease of the label strength for plain tablets, but not for film-coated and sugar-coated tablets, and hard capsules. A good correlation was found between RSDD and RSDC but not between RSDD and RSDW. These findings indicate that 1) it is difficult to rationally set the threshold level for weight variation, especially regarding the dosage forms except for plain tablets, 2) the application of weight variation tests should, in principle, be decided on the mixing homogeneity that is RSDC. 3) Most (99.6%) of the tablets and all the capsules investigated met the requirement of content uniformity test of JP13. Therefore the criteria of the JP13 content uniformity test are considered acceptable from the viewpoint of manufacturing capability.

Intensification of chemotherapy using block therapies as consolidation and reinduction therapies for acute lymphoblastic leukemia during childhood.

Between April 1994 and March 1997, 143 children (age range, 1-15 years) with newly diagnosed acute lymphoblastic leukemia (ALL), except for those patients with t(9;22), were treated according to protocol-94 of the Osaka Childhood Leukemia Study Group. In this trial, the intensity of chemotherapy was enforced in the consolidation and reinduction phases by introducing AML-type block therapies consisting of concentrated administration of 4 to 6 drugs during 5 or 6 days. For patients in the higher risk groups, rotational combination chemotherapy was introduced following the early phase. A total of 124 children with B-cell precursor ALL (B-pre ALL) were classified into 3 groups, the ultrahigh-risk group (UHRG) (15 patients), the high-risk group (HRG) (61 patients), or the standard-risk group (SRG) (48 patients), based on age. leukocyte count, immunophenotype, central nervous system leukemia, response to treatment, and selected chromosomal abnormalities. The complete remission rate was 93%, and the 6-year event-free survival (EFS) rate was 79%+/-4%. EFS rates for the UHRG, HRG, and SRG groups were 67%+/-12%, 80%+/-6%, and 81%+/-6%, respectively. Nineteen patients with T-cell ALL were treated with the protocol for the UHRG. Thirteen patients (68%) attained complete remission, and the 6-year EFS rate was 55%+/-12%. Thus, intensification of chemotherapy improved the EFS rate and AML-type block therapies appeared to be effective as the consolidation and reinduction therapies for B-pre ALL.

Developmental and transcriptional consequences of mutations in Drosophila TAF(II)60.

In vitro, the TAF(II)60 component of the TFIID complex contributes to RNA polymerase II transcription initiation by serving as a coactivator that interacts with specific activator proteins and possibly as a promoter selectivity factor that interacts with the downstream promoter element. In vivo roles for TAF(II)60 in metazoan transcription are not as clear. Here we have investigated the developmental and transcriptional requirements for TAF(II)60 by analyzing four independent Drosophila melanogaster TAF(II)60 mutants. Loss-of-function mutations in Drosophila TAF(II)60 result in lethality, indicating that TAF(II)60 provides a nonredundant function in vivo. Molecular analysis of TAF(II)60 alleles revealed that essential TAF(II)60 functions are provided by two evolutionarily conserved regions located in the N-terminal half of the protein. TAF(II)60 is required at all stages of Drosophila development, in both germ cells and somatic cells. Expression of TAF(II)60 from a transgene rescued the lethality of TAF(II)60 mutants and exposed requirements for TAF(II)60 during imaginal development, spermatogenesis, and oogenesis. Phenotypes of rescued TAF(II)60 mutant flies implicate TAF(II)60 in transcriptional mechanisms that regulate cell growth and cell fate specification and suggest that TAF(II)60 is a limiting component of the machinery that regulates the transcription of dosage-sensitive genes. Finally, TAF(II)60 plays roles in developmental regulation of gene expression that are distinct from those of other TAF(II) proteins.

Behavioral-independent features of complex heartbeat dynamics.

We test whether the complexity of the cardiac interbeat interval time series is simply a consequence of the wide range of scales characterizing human behavior, especially physical activity, by analyzing data taken from healthy adult subjects under three conditions with controls: (i) a "constant routine" protocol where physical activity and postural changes are kept to a minimum, (ii) sympathetic blockade, and (iii) parasympathetic blockade. We find that when fluctuations in physical activity and other behavioral modifiers are minimized, a remarkable level of complexity of heartbeat dynamics remains, while for neuroautonomic blockade the multifractal complexity decreases.

Assessment of gastric acidity of Japanese subjects over the last 15 years.

The gastric acidity of young to elderly Japanese subjects from 1989 to 1999 was assessed and compared with that obtained in 1984, using GA-Test capsules containing acid-dissolving granules of riboflavin. The percentage of achlorhydric subjects increased with age as observed before, however, an over all decrease in all age categories year by year was noted. The percentage of achlorhydric subjects aged 50 years in 1995-1999 was about 40%, which was lower than that (60%) in 1984. However, such a chronological change was not observed when the percentage of achlorhydric subjects was determined according to birth year, indicating that it is related to the birth year of subjects. The percentage of achlorhydric subjects correlated with infection by Helicobacter pylori. Considering the high percentage of achlorhydric elderly, bioavailability and bioequivalence studies should be performed taking into consideration the effects of gastric acidity on the in vivo performance of drug products.

Japanese guidance on bioavailability and bioequivalence.

The guideline of bioequivalence tests for generic drugs in our country was recently revised (1), and guidelines for formulation change and different strengths were published in February 2000. This paper describes those guidelines briefly.

Molecular cloning and expression during development of the Drosophila gene for the catalytic subunit of DNA polymerase epsilon.

We have cloned the genomic DNA and cDNA of Drosophila DNA polymerase epsilon (pol-epsilon) catalytic subunit (GenBank No. AB035512). The gene is separated into four exons by three short introns, and the open reading frame consists of 6660 base pairs (bp) capable of encoding a polypeptide of 2220 amino acid residues. The calculated molecular mass is 255018, similar to that of mammalian and yeast homologues. The deduced amino acid sequence of the pol-epsilon catalytic subunit shares approximately 41% identity with human and mouse homologues as well as significant homology those of C. elegans, S. cerevisiae and S. pombe. Similar to the pol-epsilon catalytic subunits from other species, the pol-epsilon catalytic subunit contains domains for DNA polymerization and 3'-5' exonuclease in the N-terminal region, and two potential zinc-finger domains in the C-terminal regions. Interestingly, a 38 amino acid sequence in the C-terminal region from amino acid positions 1823 to 1861 is similar to the site for Mycoplasma ATP binding and/or ATPase domain (GenBank No. P47365). Northern hybridization analysis indicated that the gene is expressed at the highest levels in unfertilized eggs, followed by zero to 4h embryos and adult females, and then embryos at other embryonic stages, instar larva stages and adult males. Low levels of the mRNA were also detected at the pupa stage. This pattern of expression is similar to those of DNA replication-related enzymes such as DNA polymerase alpha and delta except for the high level of expression in adult males.

DNA single-strand breaks are increased in muscle diseases with rimmed vacuoles.

Some pathological similarities between Alzheimer's disease and muscle diseases with rimmed vacuoles (RV) have been pointed out. For example, several pathological hallmark proteins have been reported to be immunopositive in the lesions of both diseases. Since apoptotic processes or primary DNA damage are suggested to play a role in the pathomechanism of Alzheimer's disease, we examined DNA double-strand breaks (DSB) and single-strand breaks (SSB) in the muscle biopsy specimens of several diseases, including muscle diseases with RV. Although no DSB-positive myonuclei were detected in any muscles examined, the number of SSB-positive myonuclei markedly increased in the muscles from cases with polymyositis and muscle diseases with RV. In polymyositis, SSB-positive myonuclei were observed in regenerating fibers and muscle fibers in the vicinity of inflammatory infiltrates, suggesting that the increase of SSB is due to muscle fiber regeneration following necrosis and inflammation. In muscle diseases with RV, however, SSB-positive myonuclei were observed in small angulated fibers and in morphologically normal fibers, regardless of necrosis, regeneration or inflammation. These findings suggest that muscle diseases with RV may share a common pathological process involving DNA damage.

Temporal contribution of body movement to very long-term heart rate variability in humans.

A newly developed, very long-term ( approximately 7 days) ambulatory monitoring system for assessing beat-to-beat heart rate variability (HRV) and body movements (BM) was used to study the mechanism(s) responsible for the long-period oscillation in human HRV. Data continuously collected from five healthy subjects were analyzed by 1) standard auto- and cross-spectral techniques, 2) a cross-Wigner distribution (WD; a time-frequency analysis) between BM and HRV for 10-s averaged data, and 3) coarse-graining spectral analysis for 600 successive cardiac cycles. The results showed 1) a clear circadian rhythm in HRV and BM, 2) a 1/f (beta)-type spectrum in HRV and BM at ultradian frequencies, and 3) coherent relationships between BM and HRV only at specific ultradian as well as circadian frequencies, indicated by significant (P < 0.05) levels of the squared coherence and temporal localizations of the covariance between BM and HRV in the cross-WD. In a single subject, an instance in which the behavioral (mean BM) and autonomic [HRV power >0.15 Hz and mean heart rate (HR)] rhythmicities were dissociated occurred when the individual had an irregular daily life. It was concluded that the long-term HRV in normal humans contained persistent oscillations synchronized with those of BM at ultradian frequencies but could not be explained exclusively by activity levels of the subjects.

TAF250 is required for multiple developmental events in Drosophila.

The TFIID transcription initiation complex is composed of TBP and multiple TAFs. Studies in unicellular systems indicate that TAF250 is required for progression through G(1)/S of the cell cycle and repression of apoptosis. Here we extend these in vivo studies by determining the developmental requirements for TAF250 in a multicellular organism, Drosophila. TAF250 mutants were isolated in a genetic screen that also yielded TAF60 and TAF110 mutants, indicating that TAFs function coordinately to regulate transcription. Null alleles of TAF250 are recessive larval lethal. However, combinations of weak loss-of-function TAF250 alleles survive to adulthood and reveal requirements for TAF250 during ovary, eye, ocelli, wing, bristle, and terminalia development as well as overall growth of the fly. These phenotypes suggest roles for TAF250 in regulating the cell cycle, cell differentiation, cell proliferation, and cell survival. Finally, molecular analysis of TAF250 mutants reveals that the observed phenotypes are caused by mutations in a central region of TAF250 that is conserved among metazoan organisms. This region is contained within the TAF250 histone acetyltransferase domain, but the mutations do not alter the histone acetyltransferase activity of TAF250 in vitro, indicating that some other aspect of TAF250 function is affected. Because this region is not conserved in the yeast TAF250 homologue, TAF145, it may define an activity for TAF250 that is unique to higher eukaryotes.

A new DNA polymerase species from Drosophila melanogaster: a probable mus308 gene product.

Harris et al. [P.V. Harris, O.M. Mazina, E.A. Leonhardt, R.B. Case, J.B. Boyd, K.C. Burtis, Molecular cloning of Drosophila mus308, a gene involved in DNA cross-link repair with homology to prokaryotic DNA polymerase I genes, Mol. Cell. Biol., 16 (1996) 5764-5771.] reported the molecular cloning of Drosophila mus308 gene, and its nucleotide and protein sequences similar to DNA polymerase I. In the present study, we attempted to find and isolate the gene product by purifying a DNA polymerase fraction not present in mus308 flies. A new DNA polymerase with properties different from those of any known polymerase species was identified and partially purified from the wild-type fly embryos through ten column chromatographies. The enzyme was resistant to aphidicolin, but sensitive to ddTTP and NEM. Human proliferating cell nuclear antigen (PCNA) and Drosophila replication protein A (RP-A) did not affect the polymerase activity. It preferred poly(dA)/oligo(dT) as a template-primer. The molecular mass was about 230 kDa with a broad peak region of 200 to 300 kDa in HiPrep16/30 Sephacryl S-300 gel filtration. These properties a different from those of all reported Drosophila polymerase classes such as alpha, beta, gamma, delta, epsilon and zeta and closely resemble those of the gene product expected from the nucleotide sequence. The new polymerase species appears to have ATPase and 3'-5' exonuclease activities as shown by the chromatographies.

Seizure with prominent tonic initial signs followed by psychomotor features: a case report clinically manifesting an unusual ictal evolution.

A clinically tonic seizure phase, immediately followed by psychomotor features (right hand dystonic posture, left hand and oral automatisms), was recorded by video and EEG, in a patient who had gliosis of the left temporal lobe and left hippocampal atrophy. Interictal epileptiform discharges were frequently seen in the left temporal area, and at the time of the tonic seizure phase, ictal spike discharges were continuously observed at the left posterior temporal area, which was recognized only by applying a high frequency filter (HFF) of 15 Hz to the digitally recorded EEG because EMG artifacts totally obscured the EEG with a HFF of 60 Hz. It is most likely that tonic seizure can occur in an adult patient with temporal lobe epilepsy, and it is speculated that an epileptogenic focus might activate a certain brain area which is regarded as a symptomatogenic zone for tonic seizures. If the tonic seizure phase is immediately followed by psychomotor features as seen in the present patient, the former could be due to focal epilepsy.

Myelodysplastic syndrome after regression of transient abnormal myelopoiesis in a Down syndrome infant: different clonal origin?

A boy with Down syndrome who developed myelodysplastic syndrome after regression of transient abnormal myelopoiesis (TAM) is described. His blast cells in TAM had other chromosome abnormalities in addition to trisomy 21;50,XY,+21c,+12,+14,+21. Serial chromosome analysis in follow-up showed abnormal clones involving monosomy 7. Myelodysplastic syndrome was diagnosed. Because two clones had different karyotypes, they might have derived from different clones.