HslO ameliorates arrested ΔrecA polA cell growth and reduces DNA damage and oxidative stress responses.

Chromosome damage combined with defective recombinase activity has been widely considered to render cells inviable, owing to deficient double-strand break repair. However, temperature-sensitive recAts polA cells grow well upon induction of DNA damage and supplementation with catalase at restrictive temperatures. These treatments reduce intracellular reactive oxygen species (ROS) levels, which suggests that recAts polA cells are susceptible to ROS, but not chronic chromosome damage. Therefore, we investigated whether polA cells can tolerate a complete lack of recombinase function. We introduced a ΔrecA allele in polA cells in the presence or absence of the hslO-encoding redox molecular chaperon Hsp33 expression plasmid. Induction of the hslO gene with IPTG resulted in increased cell viability in ΔrecA polA cells with the hslO expression plasmid. ΔrecA polA cells in the absence of the hslO expression plasmid showed rich medium sensitivity with increasing ROS levels. Adding catalase to the culture medium considerably rescued growth arrest and decreased ROS. These results suggest that hslO expression manages oxidative stress to an acceptable level in cells with oxidative damage and rescues cell growth. Overall, ROS may regulate several processes, from damage response to cell division, via ROS-sensitive cell metabolism.

Three-dimensional SAFT imaging for anisotropic materials using photoacoustic microscopy.

A pulsed laser illuminates a target zone that causes rapid thermoelastic expansion, generating broadband high-frequency ultrasonic wave (photoacoustic wave, PA wave). We developed a PA microscopy (PAM) with a confocal area of laser and ultrasonic wave for applications in nondestructive testing (NDT). The synthetic aperture focusing technique (SAFT) is applied in the PAM for the three-dimensional (3D) imaging of interior flaws. Here, we report proof-of-concept experiments for the NDT of a subsurface flaw in a thin laminar material. Graphical abstract (a) shows a specimen of carbon-fiber-reinforced plastic (CFRP) with an artificial delamination. Here, it should be noted that the group velocity varies directionally due to the strong anisotropy of the CFRP specimen (see Graphical abstract (b)). By considering the group velocity distribution in the SAFT, the shape and location of the subsurface delamination were accurately estimated as shown in Graphical abstract (c). Coating the surface of the CFRP specimen with a light-absorbent material improved the amplitude of the PA wave. This finding showed that the signal-to-noise ratio of the waves scattered from the flaws can be improved.

Restless legs syndrome is associated with headache-related disabilities in patients with migraine: a prospective 7-year follow-up study.

BACKGROUND AND PURPOSE: No prospective study has evaluated the impact of restless legs syndrome (RLS) on clinical factors in patients with migraine. We planned a prospective study to assess the impact of RLS comorbid status on clinical factors in patients with migraine. METHODS: A total of 101 patients with migraine who were evaluated for RLS twice at 7-year intervals in a university hospital setting were included in this study. The RLS group was defined as positive for RLS at either baseline or follow-up and the non-RLS group was defined as negative for RLS at both baseline and follow-up. The Migraine Disability Assessment (MIDAS) questionnaire, Beck Depression Inventory-II (BDI-II), Pittsburgh Sleep Quality Index (PSQI) and Epworth Sleepiness Scale were administered to all patients. RESULTS: The RLS prevalence was 16.8% at baseline and 20.8% at follow-up. Compared with the non-RLS group (n = 27), the RLS group (n = 74) showed a significantly higher rate of smoking and higher MIDAS and BDI-II scores at 7-year follow-up. A significant reduction in MIDAS and BDI-II scores at 7-year follow-up compared with those at baseline was observed in the non-RLS group, but not in the RLS group. The non-RLS group showed a significantly lower MIDAS score at 7-year follow-up than the RLS group after adjusting for confounding variables such as age, gender, smoking status, Epworth Sleepiness Scale and PSQI scores using analysis of covariance. The persistent RLS group (n = 11) (positive for RLS at both baseline and follow-up) showed a significantly higher rate of smoking and increased MIDAS, BDI-II and PSQI scores compared with the non-RLS group (n = 74) at 7-year follow-up. CONCLUSION: Our prospective study showed that RLS had a significant impact on headache-related disability in patients with migraine.

Exogenous serotonin regulates colorectal motility via the 5-HT2 and 5-HT3 receptors in the spinal cord of rats.

BACKGROUND: We previously reported that intrathecal injection of noradrenaline or dopamine causes enhancement of colorectal motility. As these monoamines are neurotransmitters of descending pain inhibitory pathways in the spinal cord, we hypothesized that serotonin, which is one of the neurotransmitters involved in descending pain inhibition, also influences the lumbosacral defecation center. Therefore, we examined whether serotonin acting on the spinal defecation center enhances colorectal motility. METHODS: Colorectal intraluminal pressure and propelled liquid volume were recorded in vivo in anesthetized rats. KEY RESULTS: Intrathecal injection of serotonin into the L6-S1 spinal cord elicited periodic increases in colorectal intraluminal pressure, being associated with increases in liquid output. Pharmacological experiments revealed that the effect of serotonin is mediated by both 5-HT2 and 5-HT3 receptors. The serotonin-induced enhancement of colorectal motility was unaffected even after disconnection of the defecation center from supraspinal regions by cutting the T8 spinal cord, while transection of the parasympathetic pelvic nerves prevented the colokinetic effect of serotonin. Finally, we investigated interactions among serotonin, noradrenaline and dopamine. Simultaneous administration of sub-effective doses of these monoamine neurotransmitters into the spinal cord caused propulsive colorectal motility slightly but substantially. CONCLUSIONS AND INFERENCES: These results demonstrate that exogenous serotonin acts on 5-HT2 and 5-HT3 receptors in the lumbosacral defecation center and activates the parasympathetic nervous system to enhance colorectal motility in cooperation with noradrenaline and dopamine.

Histamine-enhanced contractile responses of gastric smooth muscle via interstitial cells of Cajal in the Syrian hamster.

BACKGROUND: Gastric motility is controlled by the autonomic and enteric nervous systems and by interstitial cells of Cajal (ICCs). Although histamine is known to be released from enterochromaffin-like cells in the gastric mucosa, its regulatory roles in gastric motility are still controversial. Therefore, we investigated the functional roles of histamine in gastric motility. METHODS: Stomach preparations from hamsters were used because the stomach of hamsters can be easily separated into the forestomach and the glandular stomach. A whole preparation of the stomach was mounted in a Magnus tube, and mechanical responses were recorded using a force transducer. KEY RESULTS: Exogenous application of histamine had little effect on contractile activity of the glandular stomach. In contrast, the monoamine evoked regular, periodic contractions in the forestomach. An H1 receptor agonist reproduced the contractile responses and an H1 receptor antagonist blocked histamine-evoked contractions. Atropine and tetrodotoxin did not affect the histamine-evoked contractions. Pretreatment with drugs that inhibit the activity of ICCs abolished the effects of histamine. CONCLUSION & INFERENCES: The findings suggest that histamine regulates gastric motility by acting on ICCs via H1 receptors in the hamster. The remarkable ability of histamine to induce rhythmic contractions would be useful for treatment of gastric dysmotility.

Visualization of tumor-related blood vessels in human breast by photoacoustic imaging system with a hemispherical detector array.

Noninvasive measurement of the distribution and oxygenation state of hemoglobin (Hb) inside the tissue is strongly required to analyze the tumor-associated vasculatures. We developed a photoacoustic imaging (PAI) system with a hemispherical-shaped detector array (HDA). Here, we show that PAI system with HDA revealed finer vasculature, more detailed blood-vessel branching structures, and more detailed morphological vessel characteristics compared with MRI by the use of breast shape deformation of MRI to PAI and their fused image. Morphologically abnormal peritumoral blood vessel features, including centripetal photoacoustic signals and disruption or narrowing of vessel signals, were observed and intratumoral signals were detected by PAI in breast cancer tissues as a result of the clinical study of 22 malignant cases. Interestingly, it was also possible to analyze anticancer treatment-driven changes in vascular morphological features and function, such as improvement of intratumoral blood perfusion and relevant changes in intravascular hemoglobin saturation of oxygen. This clinical study indicated that PAI appears to be a promising tool for noninvasive analysis of human blood vessels and may contribute to improve cancer diagnosis.

Serotonin-induced contractile responses of esophageal smooth muscle in the house musk shrew (Suncus murinus).

BACKGROUND: Serotonin (5-hydroxytryptamine, 5-HT) is a regulatory factor in motility of the gastrointestinal tract including the esophagus. Although we proposed that vagal cholinergic and mast cell-derived non-cholinergic components including serotonin coordinately shorten the esophagus, the precise mechanism of serotonin-induced contractions in the suncus esophagus is still unclear. Therefore, the aims of this study were to determine characteristics of contractile responses induced by serotonin and to identify 5-HT receptor subtypes responsible for regulating motility in the suncus esophagus. METHODS: An isolated segment of the suncus esophagus was placed in an organ bath, and longitudinal or circular mechanical responses were recorded using a force transducer. KEY RESULTS: Serotonin evoked contractile responses of the suncus esophagus in the longitudinal direction but not in the circular direction. Tetrodotoxin did not affect the serotonin-induced contractions. Pretreatment with a non-selective 5-HT receptor antagonist or double application of 5-HT1 and 5-HT2 receptor antagonists blocked the serotonin-induced contractions. 5-HT1 and 5-HT2 receptor agonists, but not a 5-HT3 receptor agonist, evoked contractile responses in the suncus esophagus. CONCLUSION & INFERENCES: The findings suggest that serotonin induces contractile responses of the longitudinal smooth muscle in the muscularis mucosae of the suncus esophagus that are mediated via 5-HT1 and 5-HT2 receptors on muscle cells. The serotonin-induced contractions might contribute to esophageal peristalsis and emetic response.

Identification of a novel HLA-C allele, HLA-C*03:313, in a Japanese individual.

HLA-C*03:313 differs from HLA-C*03:04:01:01 by one non-synonymous amino acid exchange E161G.

Correction of the HLA-DQB1*04:01:01 sequence at position 79 in exon 1.

The HLA-DQB1*04:01:01 sequence is corrected at position 79 in exon 1 (G > A, Ala > Thr).

Characterization of ghrelin-sensitive neurons in the lumbosacral defecation center in rats.

BACKGROUND: Ghrelin is involved in the regulation of somatic growth, feeding behavior and energy homeostasis. Ghrelin stimulates neuropeptide Y (NPY) neurons and activates intracellular AMP-activated protein kinase (AMPK) in the hypothalamus. These NPY neurons also express the leptin receptor and leptin inhibits ghrelin-induced activation of NPY neurons. In the spinal cord, we have demonstrated colokinetic action of ghrelin. However, the precise characteristics of the ghrelin-sensitive neurons remain to be clarified. The aim of this study was firstly to confirm that the action of ghrelin is mediated via a neurogenic pathway in the spinal cord, and secondly to characterize the ghrelin-sensitive neurons by comparing with hypothalamic ghrelin-sensitive neurons. METHODS: Rats were anesthetised with alpha-chloralose and ketamine, and colorectal intraluminal pressure and expelled volume were recorded in vivo. Drugs were applied intrathecally. KEY RESULTS: Ghrelin caused enhancement of propulsive contractions. Tetrodotoxin completely blocked the colokinetic effect of ghrelin. An AMPK activator, aminoimidazole carboxamide ribonucleotide, failed to mimic the ghrelin effect. Leptin had no effect on the spontaneous contractions and did not exert a suppressive effect on the ghrelin-enhanced colorectal motility. An NPY Y1 receptor antagonist did not affect the action of ghrelin. NPY had no effect on the colorectal motility. CONCLUSIONS & INFERENCES: This study showed that intrathecal injection of ghrelin stimulates colorectal motility by acting on ghrelin-sensitive neurons in the lumbosacral defecation center. The characteristics of ghrelin-sensitive neurons in the spinal cord are quite different from those of ghrelin-sensitive neurons in the hypothalamus.

Characterization of swine leukocyte antigen alleles and haplotypes on a novel miniature pig line, Microminipig.

Microminipigs are extremely small-sized, novel miniature pigs that were recently developed for medical research. The inbred Microminipigs with defined swine leukocyte antigen (SLA) haplotypes are expected to be useful for allo- and xenotransplantation studies and also for association analyses between SLA haplotypes and immunological traits. To establish SLA-defined Microminipig lines, we characterized the polymorphic SLA alleles for three class I (SLA-1, SLA-2 and SLA-3) and two class II (SLA-DRB1 and SLA-DQB1) genes of 14 parental Microminipigs using a high-resolution nucleotide sequence-based typing method. Eleven class I and II haplotypes, including three recombinant haplotypes, were found in the offspring of the parental Microminipigs. Two class I and class II haplotypes, Hp-31.0 (SLA-1*1502-SLA-3*070102-SLA-2*1601) and Hp-0.37 (SLA-DRB1*0701-SLA-DQB1*0502), are novel and have not so far been reported in other pig breeds. Crossover regions were defined by the analysis of 22 microsatellite markers within the SLA class III region of three recombinant haplotypes. The SLA allele and haplotype information of Microminipigs in this study will be useful to establish SLA homozygous lines including three recombinants for transplantation and immunological studies.

Study of MHC class II region polymorphism in the Filipino cynomolgus macaque population.

The cynomolgus macaque (Macaca fascicularis) is currently used as an animal model in various fields of immunology especially in the development of innovative vaccines for the prevention and treatment of infectious diseases. The polymorphism of the major histocompatibility complex (MHC) influences the development of adaptive immune responses and it is crucial to characterize the polymorphism of cynomolgus MHC genes. We present here a systematic study of the MHC class II haplotypes in the Filipino macaque population. By the study of a large sample of Filipino animals (N = 353), we have characterized 18 MHC class II haplotypes by means of genotyping seven microsatellites. The animals were DRB genotyped by means of PCR-SSO or DGGE-sequencing on genomic amplified fragments. We cloned and sequenced the complementary DNA (cDNA) of DQA, DQB, DPA, and DPB genes of 117 animals. Combining the microsatellite genotyping and cDNA characterized in the 117 animals, we defined genetic association between the cDNA and the microsatellites and characterized 18 MHC class II haplotypes. For 104 animals out of the 353 studied, the presence of a recombinant haplotype was highly probable. Thirty-four percent of recombination was located in 256 kb segment between D6S2876 and D6S2747 microsatellites, a region encompassing several hot spots of recombination in the human MHC.

A novel HLA-B allele, HLA-B*44:184, identified by super high-resolution single-molecule sequence-based typing in a Japanese individual.

The novel allele HLA-B*44:184 differs from HLA-B*44:77 by three non-synonymous amino acid exchanges, T94I, L95I and S97R.

HLA-DRB1, -DRB3, -DRB4 and -DRB5 genotyping at a super-high resolution level by long range PCR and high-throughput sequencing.

Super high-resolution single molecule sequence-based typing (SS-SBT) is a human leukocyte antigen (HLA) DNA typing method to the field 4 level of allelic resolution (formerly known as eight-digit typing) to efficiently detect new and null alleles without phase ambiguity by combination of long ranged polymerase chain reaction (PCR) amplification and next-generation sequencing (NGS) technologies. We previously reported the development and application of the SS-SBT method for the eight classical HLA loci, A, B, C, DRB1, DQA1, DQB1, DPA1 and DPB1. In this article, we describe the development of the SS-SBT method for three DRB1 linked loci, DRB3, DRB4 and DRB5 (DRB3/4/5) and characterization of DRB1-DRB3/4/5 haplotype structures to the field 4 level. Locus specific PCR primers for DRB3/4/5 were designed to amplify the gene regions from intron 1 to exon 6 [3' untranslated region (3'UTR)]. In total 20 DRB1 and 13 DRB3/4/5 allele sequences were determined by the SS-SBT to the field 4 level without phase ambiguity using 19 DR51, DR52 and DR53 positive genomic DNA samples obtained from Japanese. Moreover, 18 DRB1-DRB3/4/5 haplotypes were estimated to the field 4 level by the SS-SBT method in contrast to 10 haplotypes estimated by conventional methods to the field 1 level (formerly known as two digit typing). Therefore, DRB1-DRB3/4/5 haplotyping by SS-SBT is expected to provide informative data for improved HLA matching in medical research, transplantation procedures, HLA-related disease studies and human population diversity studies.

A novel HLA-B allele, HLA-B*39:01:16, identified by super high-resolution single-molecule sequence-based typing in a Japanese individual.

HLA-B*39:01:16 differs from B*39:01:03 by one nucleotide 348 (codon 116) T to C.

Super high resolution for single molecule-sequence-based typing of classical HLA loci at the 8-digit level using next generation sequencers.

Current human leukocyte antigen (HLA) DNA typing methods such as the sequence-based typing (SBT) and sequence-specific oligonucleotide (SSO) methods generally yield ambiguous typing results because of oligonucleotide probe design limitations or phase ambiguity for HLA allele assignment. Here we describe the development and application of the super high-resolution single-molecule sequence-based typing (SS-SBT) of HLA loci at the 8-digit level using next generation sequencing (NGS). NGS which can determine an HLA allele sequence derived from a single DNA molecule is expected to solve the phase ambiguity problem. Eight classical HLA loci-specific polymerase chain reaction (PCR) primers were designed to amplify the entire gene sequences from the enhancer-promoter region to the 3' untranslated region. Phase ambiguities of HLA-A, -B, -C, -DRB1 and -DQB1 were completely resolved and unequivocally assigned without ambiguity to single HLA alleles. Therefore, the SS-SBT method described here is a superior and effective HLA DNA typing method to efficiently detect new HLA alleles and null alleles without ambiguity.

Contrasting effects of ghrelin and des-acyl ghrelin on the lumbo-sacral defecation center and regulation of colorectal motility in rats.

BACKGROUND: We have previously demonstrated that a centrally penetrant ghrelin receptor agonist enhances colorectal motility, through activation of the lumbo-sacral defecation center (L6-S1 region of the spinal cord) in rats. In the present study, we examined the effects of the native peptide and its non-acylated counterpart in eliciting this stimulatory effect on colorectal motility. METHODS: Rats were anesthetised with α-chloralose and ketamine, and colorectal intraluminal pressure and propelled intraluminal liquid volume were recorded in vivo. KEY RESULTS: Intrathecal application of acylated ghrelin to the L6-S1 region of the spinal cord, but not intravenous application, elicited groups of phasic increases in colorectal intraluminal pressure that were associated with increased fluid output through the anal cannula. The effect was dose-dependent. The colokinetic effects of ghrelin were prevented if the pelvic nerves were severed. Reverse transcription polymerase chain reaction revealed the expression of the ghrelin and ghrelin receptor genes in the lumbo-sacral spinal cord. In contrast to acylated ghrelin, des-acyl ghrelin failed to cause changes in colorectal motility. However, when des-acyl ghrelin and ghrelin were applied simultaneously at the L6-S1 region, the ghrelin-induced enhancement of colorectal motility was significantly attenuated. CONCLUSION & INFERENCES: It is concluded that acylation of the ghrelin peptide is essential to promote propulsive contractions of the colorectum and that des-acyl ghrelin opposes this effect. At most other sites of ghrelin action, des-acyl ghrelin either has no effect or it mimics ghrelin. This is the first evidence that non-acylated ghrelin opposes the action of the acylated peptide in the spinal cord.

Polymorphic major histocompatibility complex class II Alu insertions at five loci and their association with HLA-DRB1 and -DQB1 in Japanese and Caucasians.

We investigated polymorphic Alu insertion (POALIN) frequencies at five loci in the major histocompatibility complex (MHC) class II genomic region to determine their allele and haplotype frequencies and associations with the human leukocyte antigen (HLA)-DRB1 and -DQB1 genes for 100 Japanese, 174 Australian Caucasians and 67 HLA reference cell lines obtained from different ethnic groups. The POALINs varied in frequency between 11% and 57% with significant differences between the Japanese and Caucasians at three loci. One POALIN locus deviated significantly from Hardy-Weinberg equilibrium (HWE) and four POALIN loci were in significant linkage disequilibrium and had a high percentage association with a variety of HLA-DRB1 or -DQB1 two-digit alleles. Inferred haplotype analysis among two-locus, five-locus and seven-locus haplotype structures showed maximum differences between the Japanese and Caucasians with the seven-locus haplotypes. The most common multilocus haplotype in Caucasians was DRB1*1501/DQB1*0602/AluDQ1/AluDRB1/AluORF10/AluDPB2 (6.7%), whereas the second most common allele HLA-DRB1*15 (17.5%) in Japanese was associated with three or four Alu insertions. The HLA class II POALINs also differentiated within and between HLA-DRB1 super-haplotypes DR1, DR8, DR51, DR52 and DR53. This is the first comparative population study of multilocus POALINs in the HLA class II region, which shows that POALINs whether investigated alone or together with the HLA class II alleles are informative genetic markers for the identification of allele and haplotype lineages and variations within the same and/or different populations.

P2X purinoceptors mediate an endothelium-dependent hyperpolarization in longitudinal smooth muscle of anterior mesenteric artery in young chickens.

BACKGROUND AND PURPOSE: The chicken anterior mesenteric artery contains an outer longitudinal smooth muscle layer, whose neural regulation remains to be elucidated. ATP evokes a depolarization in the smooth muscle through P2Y purinoceptors. However, there may be an additional inhibitory regulation because blockade of P2Y purinoceptors converts the depolarization to hyperpolarization. The objective of the present study was to examine the mechanism underlying this hyperpolarization. EXPERIMENTAL APPROACH: Membrane potentials of longitudinal smooth muscle of the chicken mesenteric artery were recorded with a microelectrode technique. Perivascular nerves were stimulated by applying electrical field stimulation (EFS). KEY RESULTS: EFS induced a hyperpolarization in preparations obtained from 5-week-old chickens, whereas it evoked a depolarization in those from 12-week-old chickens. The EFS-evoked hyperpolarization in 5-week-old chickens was blocked by a non-specific purinoceptor antagonist, suramin, and by a specific P2X purinoceptor antagonist, pyridoxal phosphate-6-azophenyl-2',4'-disulphonic acid. Desensitization of the P2X purinoceptor with its agonist alpha,beta-MeATP significantly suppressed EFS-evoked hyperpolarization. Blockade of the P2Y purinoceptor did not affect EFS-evoked hyperpolarization. The application of the NOS inhibitor Nomega-nitro-L-arginine methyl ester or the removal of the endothelium inhibited the hyperpolarization. The application of the nitric oxide (NO) donor sodium nitroprusside mimicked the hyperpolarization. Reverse transcriptase-PCR showed that P2X purinoceptors are expressed in the endothelium of the anterior mesenteric artery. CONCLUSIONS AND IMPLICATIONS: Hyperpolarization in the longitudinal smooth muscle of the chicken anterior mesenteric artery was induced by ATP. ATP released from perivascular nerves may act on P2X purinoceptors in the endothelium and thereby stimulate NO production.

Galanin modulates vagally induced contractions in the mouse oesophagus.

Nitrergic myenteric neurons co-innervating motor endplates were previously shown to inhibit vagally induced contractions of striated muscle in the rodent oesophagus. Immunohistochemical demonstration of putative co-transmitters, e.g. galanin, in enteric neurons prompted us to study a possible role of galanin in modulating vagally mediated contractions in an in vitro vagus nerve-oesophagus preparation of the mouse. Galanin (1-16) (1-100 nmol L(-1)), in the presence of the peptidase inhibitor, phenanthroline monohydrate, inhibited vagally induced contractions in a concentration-dependent manner (control: 100%; galanin 1 nmol L(-1): 95.6 +/- 1.6%; galanin 10 nmol L(-1): 57.3 +/- 6.5%; galanin 100 nmol L(-1): 31.2 +/- 8.1%, n = 5). The non-selective galanin receptor antagonist, galantide (100 nmol L(-1)), blocked the inhibitory effect of galanin (10 nmol L(-1)) while the selective non-galanin receptor 1 and galanin receptor 3 antagonists, M871 (1 micromol L(-1)) and SNAP37889 (100 nmol L(-1)), respectively, and the nitric oxide synthase inhibitor, NG-nitro-l-arginine methyl ester (L-NAME) (200 micromol L(-1)), failed to affect this galanin-induced response. Simultaneous application of galantide (100 nmol L(-1)) and L-NAME (200 micromol L(-1)) significantly reduced the inhibitory effect of capsaicin (30 mumol L(-1)) on vagally induced contractions when compared with its effect in the presence of L-NAME alone or in combination with the selective galanin receptor 2 or 3 antagonists. An inhibitory effect of piperine on vagally induced contractions was reduced neither by galantide nor by L-NAME. Immunohistochemistry revealed galanin immunoreactive myenteric neurons and nerve fibres intermingling with cholinergic vagal terminals at motor endplates. These data suggest that galanin from co-innervating enteric neurons co-operates with nitric oxide in modulating vagally induced contractions in the mouse oesophagus.