Sex-based differences in CD103+ dendritic cells promote female-predominant Th2 cytokine production during allergic asthma.

BACKGROUND: Gender disparities in adult patients with asthma regarding its prevalence and severity are mainly due to enhanced type 2 T-helper (Th2) cytokine production in female patients compared to that in male patients. However, the pathways mediating this effect remain unclear. OBJECTIVE: We aimed to determine the roles of two major subsets of dendritic cells (DCs) in females, specifically those displaying CD11b or CD103, during enhanced Th2 priming after allergen exposure, using an ovalbumin-induced asthma mouse model. METHODS: Sex-based differences in the number of DCs at inflamed sites, costimulatory molecule expression on DCs, and the ability of DCs to differentiate naïve CD4+ T cells into Th2 population were evaluated after allergen exposure in asthmatic mice. In addition, we assessed the role of 17ß-oestradiol in CD103+ DC function during Th2 priming in vitro. RESULTS: The number of CD11bhigh DCs and CD103+ DCs in the lung and bronchial lymph node (BLN) was increased to a greater extent in female mice than in male mice at 16 to 20 hours after ovalbumin (OVA) inhalation. In BLNs, CD86 and I-A/I-E expression levels and antigen uptake ability in CD103+ DCs, but not in CD11bhigh DCs, were greater in female mice than in male mice. Furthermore, CD4+ T cells cultured with CD103+ DCs from female mice produced higher levels of interleukin (IL)-4, IL-5, and IL-13, compared with CD4+ T cells cultured with CD103+ DCs from male mice. The 17ß-oestradiol-oriented enhancement of CD86 expression on CD103+ DCs after allergen exposure induced the enhanced IL-5 production from CD4+ T cells. CONCLUSIONS AND CLINICAL RELEVANCE: These findings suggest that with regard to asthma, enhanced Th2 cytokine production in females might be attributed to 17ß-oestradiol-mediated Th2-oriented CD103+ DCs in the BLN.

Ten-year hip fracture incidence rate trends in a large California population, 1997-2006.

UNLABELLED: Hip fractures are a large public health problem with significant negative impact on an individual's overall health and survival. But while the total numbers of persons affected by hip fractures may be anticipated to increase, incidence rates appear to be declining. INTRODUCTION: To describe annual hip fracture incidence rate trends in an integrated health-care organization over 1997-2006, during which a proactive bone health program was initiated program-wide and other secular trends occurred in the population. METHODS: For this ecologic trend study, we identified all men and women ≥45 years old as of January 1 of each year. Incident fractures for each year were identified using ICD-9 diagnosis codes 820-820.9, excluding all subjects who had fractures in prior years. Annual person-time at risk for hip fracture was determined from enrollment data. Sex- and age-specific and adjusted annual incidence rates were calculated. RESULTS: The overall annual hip fracture incidence rate for men declined from 1.52/1,000 person-years in 1997 to 1.29/1,000 person-years in 2006, a 15.3% (95% confidence interval [CI]=6.2-24.5) decrease. For women, incidence declined from 2.65/1,000 person-years in 1997 to 2.24/1,000 person-years in 2006, a 15.3% (95% CI=8.7-21.9) decrease. Among subjects aged 85 years or older, incidence rates for men declined from 27.0/1,000 to 18.9/1,000 person-years, and for women they declined from 32.7/1,000 to 27.1/1,000 person-years. CONCLUSION: Hip fracture incidence has been declining in all age groups over the past 10 years. While many factors may contribute to this decline, the results are consistent with a potential benefit of the active bone health intervention.

Evolutionary transformation of the cervicobrachial plexus in the colugo (Cynocephalidae: Dermoptera) with a comparison to treeshrews (Tupaiidae: Scandentia) and strepsirrhines (Strepsirrhini: Primates).

Four cervicobrachial plexuses from two colugos (Dermoptera), which are gliding mammals with semi-elongated necks, were dissected with imaging analysis and compared with those in its relatives, 12 sides of six treeshrews (Scandentia) and 32 sides of 16 strepsirrhines (Primates), for considering of its evolutionary constraint and functional adaptation. (1) The relative cervical length in the colugos was significantly longer than those in the others, regardless of the number and proportion of vertebrae. (2) In all examined colugos, the cervical plexus exhibited broader cervical root segments comprising the hypoglossal (N. XII) and first to fifth cervical (C1-C5) nerves, whereas the brachial plexus exhibited concentrated segments comprising C6 to the first thoracic nerve (T1) and part of T2. (3) On the other hand, the cervical plexus composed of N. XII and C1-C4 and the brachial plexus composed of C5-T1(2) were formed in all treeshrews (12/12 sides, 100.0%) and most strepsirrhines (27/32 sides, 84.4%) as seen in most terrestrial placental mammals. (4) Similar root segments of broader cervical and concentrated brachial plexuses were found in five sides of three strepsirrhines (15.6%), which are species with somewhat longer necks than the other strepsirrhines and treeshrews. Based on present and previous reports on elongated and shortened neck mammals, the modified root segments of the cervicobrachial plexus in the colugo appears to be related more to neck length than to its ecological habit, specialized locomotion, or any phylogenetic constraint.

Surface Proton Conduction of Sm-Doped CeO2-δ Thin Film Preferentially Grown on Al2O3 (0001).

Sm-doped CeO2-δ (Ce0.9Sm0.1O2-δ; SDC) thin films were prepared on Al2O3 (0001) substrates by radio frequency magnetron sputtering. The prepared thin films were preferentially grown along the [111] direction, with the spacing of the (111) plane (d111) expanded by 2.6% to compensate for a lattice mismatch against the substrate. The wet-annealed SDC thin film, with the reduced d111 value, exhibited surface protonic conduction in the low-temperature region below 100 °C. The O1s photoemission spectrum exhibits H2O and OH- peaks on the SDC surface. These results indicate the presence of physisorbed water layers and the generation of protons on the SDC (111) surface with oxygen vacancies. The protons generated on the SDC surface were conducted through a physisorbed water layer by the Grotthuss mechanism.

Sex-related splenocyte function in a murine model of allergic asthma.

BACKGROUND: The prevalence and severity of asthma are higher among boys than girls, but the ratios are reversed after puberty. These observations strongly suggest that sex hormones have a role in the pathogenesis of the disease. However, the mechanisms underlying the gender differences in asthma are not fully understood. OBJECTIVE: The aim of this study was to investigate sex differences in allergic inflammation in terms of immune function. METHODS: Male and female C57BL/6 mice were sensitized and challenged with ovalbumin (OVA). OVA-specific IgE in serum and airway inflammation were compared between sexes. Splenocytes from OVA-sensitized male or female donor mice were transferred to male or female naïve recipient mice. Subsequently, the recipient mice were challenged, followed by the evaluation of OVA-specific IgE and airway inflammation. Cytokines secreted from splenocytes of the sensitized mice were measured. RESULTS: The levels of OVA-specific IgE and the allergen-induced airway inflammation were higher in female than in the male mice. The contents of T-helper type 2 (Th2) cytokines, IL-4, IL-5 and IL-13, in the bronchoalveolar lavage fluid from female mice were higher than those from male mice. The airway inflammation in female recipients transferred with splenocytes from female donors was more severe than that in any other combination of recipients and donors. Splenocytes from the sensitized female mice produced more of the Th2 cytokine, IL-5, than those from the sensitized male mice upon stimulation with OVA. CONCLUSION: Our findings suggest that the sex difference in allergic airway inflammation may be attributable to the sex difference in not only the hormonal environment but also in the immune cells themselves.

Mutations of carnitine palmitoyltransferase II (CPT II) in Japanese patients with CPT II deficiency.

Carnitine palmitoyltransferase II (CPT II) deficiency is an inherited disorder involving beta-oxidation of long-chain fatty acids. CPT II deficiency is a wide-spectrum disorder that includes a lethal neonatal form, an infantile form, and an adult-onset form. However, the ethnic characteristics and the relationship between genotype and clinical manifestation are not well understood. We investigated three non-consanguineous Japanese patients with CPT II deficiency and examined cell lines from 4 unrelated patients and 50 healthy donors. The CPT 2 gene was typed by direct DNA sequencing of polymerase chain reaction-amplified gene products. Case 1 (infantile form) was heterozygous for a phenylalanine to tyrosine substitution at position 383 (p.F383Y) and a novel valine to leucine substitution at 605 (p.V605L). Cases 2, 4, and 5 (infantile form) and case 3 (adult-onset form) were heterozygous for a single mutation at F383Y. Case 6 (adult-onset form) was compound heterozygous at the CPT 2 locus, with deletion of cytosine and thymine at residue 408, resulting in a stop signal at 420 (p.Y408fsX420), and an arginine to cysteine substitution at position 631 (p.R631C). Case 7 (adult-onset form) was homozygous for the p.F383Y mutation. In conclusion, we identified p.F383Y mutations in six of seven patients with CPT II deficiency and two novel variants of the coding gene: p.Y408fsX420 and p.V605L. These mutations differ from those in Caucasian patients, who commonly harbor p.S113L, p.P50H, and p.Q413fsX449 mutations; therefore, our data and those of other Japanese groups suggest that the p.F383Y mutation is significant in Japanese patients with CPT II deficiency.

Identification of a common mutation in Finnish patients with nonketotic hyperglycinemia.

Nonketotic hyperglycinemia (NKH) is an autosomal recessive metabolic disorder caused by the defects in the glycine cleavage system (GCS; EC 2.1.2.10), a multienzyme system that consists of four individual components. NKH is a rare disorder in many countries, but with a very high incidence in northern Finland. To understand the genetic background of this high incidence, we examined the GCS in a typical case of NKH at the molecular level. The activity of P protein, a component of the GCS, was not detected in the lymphoblasts of the patient, while P protein mRNA of a normal size and level was present in the cells. Structural analysis of P protein mRNA from the patient revealed a single nucleotide substitution from G to T in the protein coding region, which resulted in an amino acid alteration from Ser564 to Ile564. No P protein activity was detected when the mutant P protein with this amino acid substitution was expressed in COS 7 cells. The patient was homozygous for this mutation. Furthermore, this mutation was present in 70% (14 of 20) of P protein gene alleles in Finnish patients with NKH, whereas it was not found in 20 alleles of non-Finnish patients. The results suggest that this mutation is responsible for the high incidence of NKH in Finland.

Detection of pre-C and core region mutants of hepatitis B virus in chronic hepatitis B virus carriers.

We analyzed the pre-C and core region of hepatitis B virus (HBV) DNA by a polymerase chain reaction in 22 chronic carriers. In 9 hepatitis B e antigen-positive asymptomatic carriers, a single DNA band was detected at the expected size, whereas additional shorter DNA bands were observed in 7 out of 11 patients with chronic hepatitis. The smaller-sized DNAs from one chronic hepatitis patient had various lengths of deletions spanning from 105 to 183 bp in the middle of the core gene, and all deletions included common nucleotide sequences. All of the smaller-sized DNAs from the other patients proved to be variant core genes. They were deleted in similar regions by Southern analysis using oligonucleotide probes. A follow-up study revealed that four out of seven chronic hepatitis patients with a short core gene seroconverted to antibody to hepatitis B e antigen, but those with only a "wild type" did not. In another set of sequence studies, clones isolated from two chronic carriers displayed heterogeneity of the pre-C and core gene which was more often present in sera with normal alanine aminotransferase levels than with abnormal levels. These results suggest that mutant HBV alters the host immune response, and may modulate the clinical course of HBV infection. An alternative possibility is that chronic hepatitis selects for mutant forms.

Microtopography of the dual corticothalamic projections originating from domains along the frequency axis of the cat primary auditory cortex.

Spatial relationships between clusters of corticothalamic (CT) large terminals originating from cortical domains tuned to different frequencies were examined by pair-injecting two different anterograde tracers. Large-terminal CT projection originating from layer 5 was highly divergent with each injection site producing, on average, 15 local clusters distributing throughout non-lemniscal thalamic nuclei following a single anterograde tracer injection in the cat primary auditory cortex. Paired injections in higher- and lower-frequency cortical domains, resulting in labeling of two independent sets of terminal clusters, showed five recognizable patterns of spatial interaction between them. (1) In the ventral division of the medial geniculate complex (vMGC), sheet-like plexuses of small terminals of different origins were situated in parallel, with minimal overlap. (2) Extensive overlap of two low-density plexuses of differently labeled small terminals was observed in the medial division of the medial geniculate complex (MGC). (3) At the transition zones between the vMGC and the superficial dorsal nucleus of the MGC dorsal division, and between the vMGC and the ventrolateral nucleus, there were relatively broad clusters of a high density of large-terminal structures from the two cortical domains, which overlapped extensively. (4) At multiple loci in the nonlemniscal nuclei, pairing of two small clusters of differently labeled large terminals was observed. (5) Small unpaired clusters of large terminals were also found in the nonlemniscal nuclei. For large terminals, approximately 14%, 59%, and 27% clusters per injection demonstrated patterns 3, 4, and 5, respectively. The results provide evidence for the precise topographical organization for the large-terminal CT system at the microscopic level despite its highly divergent projection. This microtopographical projection from the tonotopic cortical field to non-tonotopic thalamic nuclei may raise the possibility of presence of a map that has not been defined in auditory non-lemniscal thalamic nuclei yet.

Significant correlations between the flow volume of patent ductus venosus and early neonatal liver function: possible involvement of patent ductus venosus in postnatal liver function.

BACKGROUND: The biochemical features of portosystemic venous shunt with high flow volume are hypergalactosaemia, hyperammonaemia, prolonged blood coagulation time, and raised serum bile acid concentration. The ductus venosus remains open with shunt flow in most neonates for a certain period after birth. However, the effects of blood flow through the ductus venosus on neonatal liver function remain unclear. OBJECTIVE: To elucidate the effect of patency of the ductus venosus on liver function in early neonates. METHODS: Subjects were divided into three groups by gestational age (group I, 29-32 weeks; group II, 33-36 weeks; group III, 37-41 weeks). The shunt flow volume through the ductus venosus was examined serially using ultrasonography, and correlations between flow volume and liver function in the respective groups were calculated during the first week after birth. RESULTS: Group I had a higher flow volume and later functional closure than the other two groups. Plasma ammonia and serum total bile acid concentrations correlated with flow volume in groups I and II, and blood galactose and galactose 1-phosphate concentrations correlated significantly with flow volume in group III. Percentage hepaplastin also correlated significantly with flow volume in all groups, but plasma vitamin K concentration did not in any group. CONCLUSIONS: Patent ductus venosus has a considerable effect on crucial liver functions such as ammonia detoxification, blood coagulation, and regulation of serum total bile acid concentration in early neonates.

Cloning and sequence analysis of a full length cDNA encoding human mitochondrial 3-oxoacyl-CoA thiolase.

The cDNA sequence of human mitochondrial 3-oxoacyl-CoA thiolase was determined. The nucleotide sequence contains an open reading frame of 1191 base pairs and encodes an amino acid sequence of 397 residues which exhibits 86.6% homology with that of the rat enzyme. Northern blot analysis gave a single mRNA species of 1.6 kb in the human liver, fibroblasts and intercostal muscle.

Insulin resistance associated with decreased levels of insulin-receptor messenger ribonucleic acid: evidence of a de novo mutation in the maternal allele.

Mutations in the insulin receptor gene may lead to insulin resistance and diabetes mellitus in some patients. We have studied an insulin-resistant patient with leprechaunism. Insulin binding to the patient's fibroblasts was markedly decreased. Determination of the nucleotide sequence of the patient's insulin receptor gene revealed heterozygosity for a 2-basepair deletion in exon 15. If the premessenger ribonucleic acid (pre-mRNA) is spliced normally, it causes a replacement of codon 970 in the beta-subunit with a premature chain termination codon, thereby deleting most of the intracellular domain of the receptor. The mRNA transcribed from the allele with a 2-base-pair deletion is likely to be unstable because mRNA transcripts from this allele could not be detected by complementary DNA sequencing. Northern blot analysis showed that the patient's insulin receptor mRNA was decreased by 90% compared with that of a control subject, thus suggesting that the patient is a compound heterozygote for two mutations that decrease levels of insulin receptor mRNA. This deletion mutation in exon 15 seems to be a de novo mutation, because it was not detected in either parent. Investigation of the inheritance of a silent sequence polymorphism in exon 17 provided that the deletion occurred in the maternal allele. Furthermore, linkage analysis suggests that the second mutation is derived from the patient's father, although we could not directly identify it by sequencing the coding region of the insulin receptor gene. Therefore, it is possible that this mutation is present in a regulatory domain of the insulin receptor gene, acting in cis-dominant fashion to reduce the levels of insulin receptor mRNA. Analyses of the hypervariable region in the myoglobin and pMCT118 loci were consistent with the assumption that the father and mother studied here are indeed the biological parents of the diseased patient. We hereby conclude that the patient is a compound heterozygote for two mutant alleles, both of which are responsible for the reduced levels of insulin receptor mRNA and insulin binding.

No enzyme activity of 25-hydroxyvitamin D3 1alpha-hydroxylase gene product in pseudovitamin D deficiency rickets, including that with mild clinical manifestation.

Pseudovitamin D deficiency rickets (PDDR) is an autosomal recessive disorder caused by defect in the activation of vitamin D. We recently isolated 25-hydroxyvitamin D3 1alpha-hydroxylase gene and identified four homozygous inactivating missense mutations in this gene by analysis of four typical cases of PDDR. This disease shows some phenotypic variation, and it has been suspected that patients with mild phenotypes have mutations that do not totally abolish the enzyme activity. To investigate the molecular defects associated with the phenotypic variation, we analyzed six additional unrelated PDDR patients: one with mild and five with typical clinical manifestation. By sequence analysis, all six patients were proven to have mutations in both alleles. The mutations varied, and we identified four novel missense mutations, a nonsense mutation, and a splicing mutation for the first time. The patient with mild clinical symptoms was compound heterozygous for T321R and a splicing mutation. The splice site mutation caused intron retention. Enzyme activity of the T321R mutant was analyzed by overexpressing the mutant 1alpha-hydroxylase in Escherichia coli cells to detect the subtle residual enzyme activity. No residual enzyme activity was detected in T321R mutant or in the other mutants. These results indicate that all of the patients, including those of mild phenotype, are caused by 1alpha-hydroxylase gene mutations that totally abolish the enzyme activity.

A 15N-1H nuclear magnetic resonance study on the interaction between isoleucine tRNA and isoleucyl-tRNA synthetase from Escherichia coli.

Imino 15N and 1H resonances of Escherichia coli tRNA(lIle) were observed in the absence and presence of E coli isoleucyl-tRNA synthetase. Upon complex formation of tRNA(lIle) with isoleucyl-tRNA synthetase, some imino 15N-1H resonances disappeared, and some others were significantly broadened and/or shifted in the 1H chemical shift, while the others were observed at the same 15N-1H chemical shifts. It was indicated that the binding of tRNA(lIle) with IleRS affect the following four regions: the anticodon stem, the junction of the acceptor and T stems, the middle of the D stem, and the region where the tertiary base pair connects the T, D, and extra loops. This result is consistent with those of chemical footprinting and site-directed mutagenesis studies. Taken together, these three independent results reveal the recognition mechanism of tRNA(lIle) by IleRS: IleRS recognizes all the identity determinants distributed throughout the tRNA(lIle) molecule, which induces changes in the secondary and tertiary structures of tRNA(lIle).

Cortical convergence from different frequency domains in the cat primary auditory cortex.

Primary auditory cortex (AI) has a tonotopic map consisting of orderly isofrequency (IF) bands, and cortical connections are commonly supposed to link domains preferring similar characteristic frequencies (CFs) within AI and in auditory association cortex. The interaction of different frequency channels, however, has not fully been understood in terms of anatomical substrates. Here, by injecting two anterograde tracers in different frequency domains of cat AI, without overlap of the injection cores, we attempted to relate the anatomical mapping of cortical outputs to physiologically defined fields in the auditory cortex. Consistent with previous studies, patches of labeled axon terminals were oriented largely along the IF axis. In regions distant from the injection sites, however, terminal patches were divergent in distribution. This divergence resulted in a complex geometry of partial overlap of projections originating from the two injection sites. The relative extent of the overlap tended to vary depending on the distance between the two injection sites. Physiological mapping for tonotopy across auditory fields revealed that projectional overlap was characteristic of dorsal AI and the dorsoposterior field and, to a lesser extent, in the secondary auditory field. Considering the differences in frequency representation in different AI IF bands, the anatomical convergence of projections tuned to different CFs could contribute to the spectral integration of sound components. Furthermore, the different extent of convergence in the functionally distinct fields might reflect field-specific processing of acoustic signals.

Inhibition by troglitazone of the antigen-induced production of leukotrienes in immunoglobulin E-sensitized RBL-2H3 cells.

1. The effect of troglitazone, an anti-diabetic drug with insulin-sensitizing action, on antigen-induced production of leukotriene (LT) B(4), C(4) and E(4) and prostaglandin D(2) (PGD(2)) was examined in dinitrophenol (DNP)-specific immunoglobulin E (IgE)-sensitized RBL-2H3 mast cells following stimulation by the antigen, DNP-conjugated human serum albumin. Levels of LTB(4), C(4) and E(4) and PGD(2) in the conditioned medium were enzyme-immunoassayed. 2. Troglitazone inhibited the antigen-induced production of LTB(4), C(4) and E(4) and the potency of the inhibition was comparable to that of zileuton, a specific inhibitor of 5-lipoxygenase (5-LOX) and a clinically used anti-asthmatic drug. Neither troglitazone nor zileuton affected antigen-induced production of PGD(2), arachidonic acid release from membrane phospholipids and degranulation. 3. Troglitazone inhibited LTB(4) production by the supernatant fraction of RBL-2H3 cell lysate with similar potency to zileuton, suggesting that troglitazone inhibits LT production by direct inhibition of 5-LOX activity. 4. Furthermore, it was shown that troglitazone as well as zileuton inhibited LTB(4) production in A23187-stimulated rat peritoneal neutrophils. 5. These findings suggest that troglitazone inhibits antigen-induced LT production in the IgE-sensitized RBL-2H3 cells and A23187-stimulated rat peritoneal neutrophils by direct inhibition of 5-LOX activity.

Effects of N(G)-nitro-L-arginine methyl ester on endotoxin-induced leakage of lactate dehydrogenase and cytotoxicity in J774A.1 cells.

In the present study, we investigated the effects of the nitric oxide (NO) synthase inhibitor N(G)-nitro-L-arginine-methyl ester (L-NAME) on tissue injury or cytotoxicity caused by endotoxin challenge by assaying lactate dehydrogenase (LDH) isozymes and cell viability in J774A.1 cells. In mice treated with L-NAME (10 mg kg(-1), i.v.), the activity of LDH in serum 18 h after endotoxin (6 mg kg(-1), i.p.) injection was not significantly different from that in mice treated with endotoxin alone. Mice injected with endotoxin exhibited leakage of LDH isozymes 3 and 5, but L-NAME did not protect against endotoxin-induced acute leakage of LDH isozymes. Treatment with L-NAME (10-1000 microM) significantly inhibited NO generation by endotoxin (1 microg ml(-1))-activated J774A.1 cells. However, L-NAME (10-1000 microM) did not affect endotoxin-induced cytotoxicity in J774A.1 cells. These findings suggested that endotoxin-induced NO formation may not contribute to tissue injury or cytotoxicity caused by endotoxin.

Use of two anterograde axon tracers to label distinct cortical neuronal populations located in close proximity.

In order to investigate converging projections originating from adjacent populations of cortical neurons, injections of two different anterograde tracers, biotinylated dextranamine (BDA) and Phaseolus vulgaris leucoagglutinin (PHA-L), were made in close proximity. When the two injection sites were separated by around 500 microm and the time between injections was 1--4 h, BDA-labeling of neuronal elements was found not only at the BDA injection site but also at the PHA-L injection site. This false-positive BDA labeling of neurons at the PHA-L injection site was so intense that labeled axons could be traced, both into the neighboring cortical gray matter and into white matter. Increasing the separation distance to 1000 microm resulted in much fewer falsely positive labeled neurons at the PHA-L injection site. Even more effective was extending the time interval between the two injections. Thus, if the BDA injection preceded the PHA-L injection by more than 12 h, virtually no false-positive labeling was associated with the PHA-L injection site. These procedures may be applied to other combinations of anterograde tracers, such as BDA with tetramethylrhodamine-conjugated dextran amine.

A follow up study of myocardial involvement in patients with mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS).

OBJECTIVE: To investigate cardiac function in patients with mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) and clarify the clinical features of cardiomyopathy in MELAS. PATIENTS: 11 consecutive patients with MELAS (mean age at initial examination 11.3 years, range 4 to 16 years) were enrolled in the study. Six were followed for more than five years. RESULTS: On echocardiographic examination, three patients showed increased left ventricular end diastolic posterior wall thickness (LVPWTd), exceeding 140% of the normal value. Four patients, including these three, had an ejection fraction of less than 50%, and two also had increased left ventricular end diastolic volume (LVEDV) exceeding 140% of the normal value (%N). The LVPWTd%N was correlated positively with the LVEDV%N (R = 0.669, p < 0.05) and negatively with the ejection fraction (R = -0.6701, p < 0.05). One patient died of heart failure aged 22 years. CONCLUSIONS: The cardiomyopathy in MELAS is characterised by an abnormally thick left ventricular wall with progressive dilatation and poor left ventricular contraction developing over several years, indicating hypertrophic cardiomyopathy advancing to dilated cardiomyopathy.

Additional evidence for blepharismin photoreceptor pigment mediating step-up photophobic response of unicellular organism, Blepharisma.

In the ciliated protozoan, Blepharisma japonicum, the pink-colored pigment (blepharismin) contained in the pigment granules is believed to be the photoreceptor pigment responsible for the step-up photophobic response. When the cells partially bleached by extrusion of the pigment granules caused by cold shock were subsequently cultured under illuminated conditions, the pigment-less granules regenerated and the cells were further bleached (pigment content below 0.5%). The photosensitivity of such colorless cells disappeared completely. In contrast, the blepharismin pigment regenerated gradually when such colorless cells were transferred to darkness. The photosensitivity of the cells also recovered with regeneration of the pigment. We found that blepharismin pigment was not photobleached in the absence of O2. The step-up photophobic response was also completely repressed in the absence of O2. These results strongly confirm that blepharismin is a photoreceptor pigment mediating photobehavior of Blepharisma and that O2 is required for the early step in the phototransduction of the light-excited pigment.