Quantitative PCR detection of feline morbillivirus in cat urine samples

Feline morbillivirus (FmoPV) is a new virus species and its detection is important, since correlation has been reported between FmoPV virus infection and tubulointerstitial nephritis in cats. Here, we report a real-time reverse transcription (RT)-PCR system that can detect the FmoPV L-gene sequence with more than 10-time higher sensitivity than a conventional PCR system, resulting in detection of less than 10 copies of the template DNA. The total FmoPV positive rate of urine samples from veterinary clinics and hospitals in Japan was 15.1% (25/166) using this system. This study demonstrates usefulness of the real-time RT-PCR system for detection of FmoPV for cat urine samples.

Use of S1 nuclease in deep sequencing for detection of double-stranded RNA viruses

Metagenomic approach using next-generation DNA sequencing has facilitated the detection of many pathogenic viruses from fecal samples. However, in many cases, majority of the detected sequences originate from the host genome and bacterial flora in the gut. Here, to improve efficiency of the detection of double-stranded (ds) RNA viruses from samples, we evaluated the applicability of S1 nuclease on deep sequencing. Treating total RNA with S1 nuclease resulted in 1.5–28.4- and 10.1–208.9-fold increases in sequence reads of group A rotavirus in fecal and viral culture samples, respectively. Moreover, increasing coverage of mapping to reference sequences allowed for sufficient genotyping using analytical software. These results suggest that library construction using S1 nuclease is useful for deep sequencing in the detection of dsRNA viruses.

Ten-year incidences of self-reported non-vertebral fractures in Japanese patients with rheumatoid arthritis: discrepancy between disease activity control and the incidence of non-vertebral fracture

Despite improvements in rheumatoid arthritis disease activity of in the past 10 years, the incidence of self-reported non-vertebral fractures did not decrease in our cohort of 9,987 patients. This study may indicate that osteoporosis treatment and non-vertebral fracture prevention remain important regardless of the rheumatoid arthritis disease activity.

INTRODUCTION

Although rheumatoid arthritis (RA) is a risk factor for osteoporosis and fractures, few studies have described the association between disease activity and the fracture incidence in patients with RA. This study aimed to investigate changes in the non-vertebral fracture incidence between 2001 and 2010 in our Institute of Rheumatology Rheumatoid Arthritis (IORRA) cohort.

METHODS

The IORRA is a prospective observational cohort study of Japanese RA patients. A total of 9,987 patients with RA were enrolled in this cohort from 2000 to 2010. The clinical parameter and non-vertebral fracture occurrence data were collected biannually through self-reported questionnaires. Incidences of self-reported non-vertebral fractures were also analyzed via standardization according to gender, age, and disease activity during each 2-year period.

RESULTS

From 2001 to 2010, the percentage of patients with 28-joint disease activity score remission increased from 7.8 to 39.7%, prednisolone intake decreased from 51.4 to 41.3%, and bisphosphonate intake increased from 5.0 to 23.4%. The non-vertebral fracture incidence rates were 24.6/1,000 person-years in 2001 and 35.5/1,000 person-years in 2010, with no apparent change even after standardization. The overall non-vertebral fracture incidence was significantly higher in the autumn/winter than in the spring/summer (p = 0.02).

CONCLUSION

Despite improvements in disease activity and functional disability, the non-vertebral fracture incidence exhibited no apparent change between 2001 and 2010 in our patients with RA. Osteoporosis treatment and non-vertebral fracture prevention remain important regardless of the disease control in patients with RA.

H2 genotypes of G4P[6], G5P[7], and G9[23] porcine rotaviruses show super-short RNA electropherotypes

During group A rotavirus (RVA) surveillance of pig farms in Japan, we detected three RVA strains (G4P[6], G5P[7], and G9P[23] genotypes), which showed super-short RNA patterns by polyacrylamide gel electrophoresis, in samples from a healthy eight-day-old pig and two pigs of seven and eight days old with diarrhea from three farms. Reverse transcription PCR and sequencing revealed that the full-length NSP5 gene of these strains contained 952 or 945 nucleotides, which is consistent with their super-short electropherotypes. Due to a lack of whole genome data on Japanese porcine RVAs, we performed whole genomic analyses of the three strains. The genomic segments of these RVA strains showed typical porcine RVA constellations, except for H2 NSP5 genotype, (G4,5,9-P[6,7,23]-I5-R1-C1-M1-A8-N1-T1-E1-H2 representing VP7-VP4-VP6-VP1-VP2-VP3-NSP1-NSP2-NSP3-NSP4-NSP5 genes). In phylogenetic analyses, these porcine RVA strains clustered with porcine and porcine-like human RVA strains and showed a typical porcine RVA backbone, except for the NSP5 gene; however, intra-genotype reassortment events among porcine and porcine-like human RVA strains were observed. The NSP5 gene segments of these strains were clustered within the H2b genotype with super-short human RVA strains. The H2 genotype has to date only been identified in human and lapine RVA strains. Thus, to our knowledge, this report presents the first case of H2 NSP5 genotype showing a super-short RNA pattern in porcine RVA. These data suggest the possibility of interspecies transmission between pigs and humans and imply that super-short porcine RVA strains possessing H2 genotype are circulating among both asymptomatic and diarrheic porcine populations in Japan.

Identification of a natural recombination in the F and H genes of feline morbillivirus

Feline morbillivirus (FmoPV) has recently been identified in Hong Kong and Japan. FmoPV is considered to belong to the genus Morbillivirus, in the family Paramyxoviridae. In this study, the complete nucleotide sequences of three strains of FmoPV detected in cats in Japan were determined. Among the six genes in FmoPV; N, P/V/C, M, F, H and L, the P gene showed the highest polymorphism in the nucleotide and putative amino acid sequences among the FmoPV strains. There was no geographical association in terms of the FmoPV phylogeny; however, from extensive phylogenetic and recombination analyses, we found that one Japanese FmoPV strain, MiJP003, was a probable recombinant between two virus strains in the independent lineages found in Japan and Hong Kong, respectively. The recombination was considered to have occurred within the F and H genes. Such recombination is thought to be involved in the evolution of FmoPV.

Existence of feline morbillivirus infection in Japanese cat populations

Feline morbillivirus (FmoPV) is a member of a new virus species that has only been found in the Hong Kong cat population. For the first time, however, we have now detected nucleotide sequences similar to FmoPV in samples from Japanese cat populations. The positive rates for urine and blood samples from Japanese cats were 6.1 % (5/82) and 10 % (1/10), respectively. These sequences are similar to the previously reported FmoPV, with 92-94 % identity, and substantially different from all other morbilliviruses. Phylogenetic analysis of the identified Japanese FmoPVs and other morbilliviruses demonstrated a pattern similar to those previously published for the FmoPV viruses isolated in Hong Kong. FmoPV RNA was also detected from formalin-fixed paraffin-embedded (FFPE) kidney tissues of cats with nephritis, with a positive rate of 40 % (4/10). By using nested-set primers based on the FmoPV sequence and RNA from FFPE tissues, we demonstrated the existence of FmoPV infection in Japanese cats and established the method for detection of the FmoPV RNA from kidney tissues prepared for pathology examinations, which is useful for studies on the pathogenicity of the virus.

Detection of bovine group a rotavirus using rapid antigen detection kits, rt-PCR and next-generation DNA sequencing

We investigated the sensitivity of human rotavirus rapid antigen detection (RAD) kits, RT-PCR and next-generation DNA sequencing (NGS) for detection of bovine group A rotavirus (RVA). The Dipstick 'Eiken' Rota (Dipstick) showed the highest sensitivity out of the seven RAD kits against all selected strains in limited dilution analyses, which was consistent with the results for equine rotavirus previously reported. RT-PCR had 10⁰-10³-fold higher sensitivity than the Dipstick. NGS using thirteen RT-PCR-negative fecal samples revealed that all samples yielded RVA reads and especially that two of them covered all 11 genome segments. Moreover, mapping reads to reference sequences allowed genotyping. The NGS would be sensitive and useful for analysis of less dependent on specific primers and screening of genotypes.

Prediction of contralateral inguinal hernias in children: a prospective study of 357 unilateral inguinal hernias

Purpose

Previously, we established a pre-operative risk scoring system to predict contralateral inguinal hernia in children with unilateral inguinal hernias. The current study aimed to verify the usefulness of our pre-operative scoring system.

Methods

This was a prospective study of patients undergoing unilateral inguinal hernia repair from 2006 to 2009 at a single institution. Gender, age at initial operation, birth weight, initial operation side, and the pre-operative risk score were recorded. We analyzed the incidence of contralateral inguinal hernia, risk factors, and the usefulness of our pre-operative risk scoring system. The follow-up period was 36 months. We used forward multiple logistic regression analysis to predict contralateral hernia.

Results

Of the 372 patients who underwent unilateral hernia repair, 357 (96.0 %) were completely followed-up for 36 months, and 23 patients (6.4 %) developed a contralateral hernia. Left-sided hernia (OR = 5.5, 95 %, CI = 1.3–24.3, p = 0.023) was associated with an increased risk of contralateral hernia. The following covariates were not associated with contralateral hernia development: gender (p = 0.702), age (p = 0.215), and birth weight (p = 0.301). The pre-operative risk score (cut-off point = 4.5) of the patients with a contralateral hernia was significantly higher, compared with the patients without a contralateral hernia using the area under the receiver operating characteristic curve (p = 0.024).

Conclusions

Using multivariate analysis, we confirmed usefulness of our pre-operative scoring system and initial side of the inguinal hernia, together, for the prediction of contralateral inguinal hernia in children.

Effect of co-culture with intact embryos on development of bovine separated blastomeres

To improve embryo development in bovine separated blastomeres, we evaluated applicability of co-culture with intact embryos. The morphological quality of blastocysts derived from separated blastomeres and rate of blastocyst formation were only slightly increased when the cells were co-cultured with intact embryos, which did not provide significant differences when statistically analyzed. However, the cell count of inner cell mass (ICM), trophectoderm (TE) and total number of cells in Day 8 blastocysts were significantly higher when the cells were co-cultured with the intact embryos than those with the cells cultured individually (P<0.05). Transfer of four monozygotic pairs of blastocysts derived from the cells co-cultured with intact embryos led to three pregnancies even when the blastomeres were produced by in vitro maturation and in vitro fertilization of oocytes collected by ovum pick-up from elite cows. These results suggest that co-culturing with intact embryos may enhance development of bovine separated blastomere.

Risk factors associated with the occurrence of hip fracture in Japanese patients with rheumatoid arthritis: a prospective observational cohort study

Risk factors associated with the occurrence of hip fracture in Japanese patients with rheumatoid arthritis (RA) were evaluated in a prospective, observational cohort study. Physical disability, advanced age, history of total knee replacement (TKR), and low body mass index (BMI) appear to be associated with the occurrence of hip fracture.

INTRODUCTION

This study seeks to evaluate the association between potential risk factors and the occurrence of hip fractures in Japanese RA patients.

METHODS

A total of 9,720 patients (82.1% female; mean age, 55.7 years) with RA were enrolled in a prospective observational study from 2000 to 2010. Self-reported hip fractures were verified using patient medical records. Cox proportional hazards models were used to analyze independent contributions of various risk factors to hip fracture occurrence.

RESULTS

During a mean follow-up of 5.2 years, 152 patients reported 152 hip fractures. Among these patients, 97 hip fractures in 97 patients (15 males, 82 females) were verified with medical records. Japanese version of the Health Assessment Questionnaire (J-HAQ) disability score [per 1 score, hazard ratio (HR), 2.64; 95% confidence interval (CI), 1.94-3.58], age (per 10 years; HR, 1.53; 95% CI, 1.25-1.87), history of TKR (HR, 3.75; 95% CI, 1.57-8.96), and BMI (per 1 kg/m2, HR, 0.92; 95% CI, 0.86-0.99) were significantly associated with hip fractures. Among the scores on the eight domains of the J-HAQ, J-HAQ (arising) (HR, 1.74; 95% CI, 1.28-2.36) and J-HAQ (hygiene) (HR, 1.58; 95% CI, 1.11-2.24) were significantly correlated with the occurrence of hip fracture.

CONCLUSIONS

High J-HAQ disability score, advanced age, history of TKR, and low BMI appear to be associated with the occurrence of hip fractures in Japanese RA patients. Among the eight domains of the J-HAQ, arising and hygiene disabilities appear to be correlated with the occurrence of hip fractures in this patient population.

Spontaneous migration of a redundant nerve root accompanied by absorption of lumbar disk herniation. A case report

A redundant nerve root is defined as a large, elongated and tortuous nerve root commonly associated with severe lumbar spinal canal stenosis. Elongation of nerve roots as a result of mechanical trapping at stenotic level is assumed to be a possible mechanism. Here we present a case in a patient who showed a redundant nerve root above the level of a lumbar canal stenosis caused by disk herniation and redundancy spontaneously migrating to a lower lumbar stenosis level accompanied by absorption of the herniated disk as shown by magnetic resonance imaging (MRI). A 67-year-old Japanese woman presented with bilateral thigh/leg pain and intermittent claudication. A midsagittal T2-weighted MR image of the lumbar spine revealed severe spinal canal stenosis at the L3-4 and L4-5 levels. At the L3-4 level, central disk herniation compressed the dural tube. An MR image revealed redundant nerve roots just cranial to the severely compressed L3-4 level. A follow-up MRI study revealed regression of disk herniation at the L3-4 level. In contrast, there was no significant change of the stenosis at the L4-5 level. Sagittal T2-weighted MR imaging at follow-up revealed redundant nerve roots just cranial to the L4-5 level, whereas the redundant nerve roots cranial to the L3-4 level had disappeared. The MRI findings of the present case support the "squeeze" hypothesis as causative of redundant nerve roots.