FRAX score and recent fall history predict the incidence for sarcopenia in community-dwelling older adults: a prospective cohort study.

We hypothesized that the baseline FRAX score and previous falls would predict the incidence of sarcopenia in community-dwelling older adults who received medical check-ups. The FRAX score (hazard ratio [HR] = 1.087, 95% CI 1.014-1.167) and previous falls (HR = 5.181, 95% CI 1.002-26.777) were determined to be independent risk factors for the incidence of sarcopenia. PURPOSE: This prospective study was performed to elucidate the prevalence and incidence of sarcopenia in community-dwelling older adults who received medical check-ups, and to determine whether FRAX score and fall history predict the incidence of sarcopenia. METHODS: Participants were recruited from a group of individuals who had registered for an annual town-sponsored medical check-up. Study inclusion criteria were aged older than 60 years, living independently, and ability to walk without assistance. Individuals who received nursing care were excluded from the study. A total of 426 residential participants were analyzed. Demographic information, fall history of the previous year, and FRAX score without bone mineral density were assessed. The assessment for sarcopenia was based on the recommendations of the Asian Working Group for Sarcopenia. RESULTS: The final sample for the assessment of sarcopenia incidence comprised 258 participants. The mean follow-up time was 2.92 years. The rate of sarcopenia was 1.06 cases per 100 person-years at risk. The Cox multivariate logistic regression model in our analysis was adjusted for age, gender, muscle mass, and covariates and showed that the FRAX score (HR = 1.087, 95% CI 1.014-1.167) and recent history of falls (HR = 5.181, 95% CI 1.002-26.777) were independent risk factors for the incidence of sarcopenia. CONCLUSION: FRAX and history of falling can be a simple screening tool to raise awareness of the prevention of osteoporosis and sarcopenia in clinical settings.

Novel biallelic SZT2 mutations in 3 cases of early-onset epileptic encephalopathy.

The seizure threshold 2 (SZT2) gene encodes a large, highly conserved protein that is associated with epileptogenesis. In mice, Szt2 is abundantly expressed in the central nervous system. Recently, biallelic SZT2 mutations were found in 7 patients (from 5 families) presenting with epileptic encephalopathy with dysmorphic features and/or non-syndromic intellectual disabilities. In this study, we identified by whole-exome sequencing compound heterozygous SZT2 mutations in 3 patients with early-onset epileptic encephalopathies. Six novel SZT2 mutations were found, including 3 truncating, 1 splice site and 2 missense mutations. The splice-site mutation resulted in skipping of exon 20 and was associated with a premature stop codon. All individuals presented with seizures, severe developmental delay and intellectual disabilities with high variability. Brain MRIs revealed a characteristic thick and short corpus callosum or a persistent cavum septum pellucidum in each of the 2 cases. Interestingly, in the third case, born to consanguineous parents, had unexpected compound heterozygous missense mutations. She showed microcephaly despite the other case and previous ones presenting with macrocephaly, suggesting that SZT2 mutations might affect head size.

Isolation and characterization of avian influenza viruses from raw poultry products illegally imported to Japan by international flight passengers.

The transportation of poultry and related products for international trade contributes to transboundary pathogen spread and disease outbreaks worldwide. To prevent pathogen incursion through poultry products, many countries have regulations about animal health and poultry product quarantine. However, in Japan, animal products have been illegally introduced into the country in baggage and confiscated at the airport. Lately, the number of illegally imported poultry and the incursion risk of transboundary pathogens through poultry products have been increasing. In this study, we isolated avian influenza viruses (AIVs) from raw poultry products illegally imported to Japan by international passengers. Highly (H5N1 and H5N6) and low (H9N2 and H1N2) pathogenic AIVs were isolated from raw chicken and duck products carried by flight passengers. H5 and H9 isolates were phylogenetically closely related to viruses isolated from poultry in China, and haemagglutinin genes of H5N1 and H5N6 isolates belonged to clades 2.3.2.1c and 2.3.4.4, respectively. Experimental infections of H5 and H9 isolates in chickens and ducks demonstrated pathogenicity and tissue tropism to skeletal muscles. To prevent virus incursion by poultry products, it is important to encourage the phased cleaning based on the disease control and eradication and promote the reduction in contamination risk in animal products.

Mediastinoscopic extended thymectomy for pediatric patients with myasthenia gravis.

BACKGROUND: Extended thymectomy is indicated for children with myasthenia gravis (MG) when drug-resistance or dependence is seen. We have employed a technique for mediastinoscopic extended thymectomy (MET) on children with MG. METHOD: A total of 14 children underwent MET at Kanagawa Children's Medical Center between 2005 and 2013. A mediastinal operation field was made by a V-shaped hook infrasternally to extirpate the thymus with adipose tissue around the thymus. RESULTS: The operation time and the amount of blood loss were 182±44 minutes and 34±43 ml, respectively. Postoperative complications, in the form of transient paralysis of the right recurrent nerve, occurred in 2 patients. The median length of postoperative hospital stay was 4.5 days. After MET, 6 patients achieved complete remission and 7 patients achieved steroid dose reduction, but no improvement was seen in 1 patient. CONCLUSIONS: This procedure offers the advantage of good surgical access for dissection around the bilateral phrenic nerves in extended total thymectomy, while achieving good cosmetic results.

Genotype-phenotype correlation of contiguous gene deletions of SLC6A8, BCAP31 and ABCD1.

The BCAP31 gene is located between SLC6A8, associated with X-linked creatine transporter deficiency, and ABCD1, associated with X-linked adrenoleukodystrophy. Recently, loss-of-function mutations in BCAP31 were reported in association with severe developmental delay, deafness and dystonia. We characterized the break points in eight patients with deletions of SLC6A8, BCAP31 and/or ABCD1 and studied the genotype-phenotype correlations. The phenotype in patients with contiguous gene deletions involving BCAP31 overlaps with the phenotype of isolated BCAP31 deficiency. Only deletions involving both BCAP31 and ABCD1 were associated with hepatic cholestasis and death before 1 year, which might be explained by a synergistic effect. Remarkably, a patient with an isolated deletion at the 3'-end of SLC6A8 had a similar severe phenotype as seen in BCAP31 deficiency but without deafness. This might be caused by the disturbance of a regulatory element between SLC6A8 and BCAP31.

Phenotype and genotype in 101 males with X-linked creatine transporter deficiency.

BACKGROUND: Creatine transporter deficiency is a monogenic cause of X-linked intellectual disability. Since its first description in 2001 several case reports have been published but an overview of phenotype, genotype and phenotype--genotype correlation has been lacking. METHODS: We performed a retrospective study of clinical, biochemical and molecular genetic data of 101 males with X-linked creatine transporter deficiency from 85 families with a pathogenic mutation in the creatine transporter gene (SLC6A8). RESULTS AND CONCLUSIONS: Most patients developed moderate to severe intellectual disability; mild intellectual disability was rare in adult patients. Speech language development was especially delayed but almost a third of the patients were able to speak in sentences. Besides behavioural problems and seizures, mild to moderate motor dysfunction, including extrapyramidal movement abnormalities, and gastrointestinal problems were frequent clinical features. Urinary creatine to creatinine ratio proved to be a reliable screening method besides MR spectroscopy, molecular genetic testing and creatine uptake studies, allowing definition of diagnostic guidelines. A third of patients had a de novo mutation in the SLC6A8 gene. Mothers with an affected son with a de novo mutation should be counselled about a recurrence risk in further pregnancies due to the possibility of low level somatic or germline mosaicism. Missense mutations with residual activity might be associated with a milder phenotype and large deletions extending beyond the 3' end of the SLC6A8 gene with a more severe phenotype. Evaluation of the biochemical phenotype revealed unexpected high creatine levels in cerebrospinal fluid suggesting that the brain is able to synthesise creatine and that the cerebral creatine deficiency is caused by a defect in the reuptake of creatine within the neurones.

Acute encephalopathy in a patient with Dravet syndrome.

Dravet syndrome (severe myoclonic epilepsy in infancy) is an epileptic syndrome with various types of seizures that begin in the first year of life and may result in intellectual impairment. Mutations of the SCN1A gene are the most prevalent genetic cause of Dravet syndrome. In this study, we report a 12-year-old girl with Dravet syndrome carrying an SCN1A mutation, c.2785Cdel (L929del fsX934). She had an episode of status epilepticus and persistent lethargy after 48 h of acute febrile illness that was preceded by an annual flu vaccination. Low voltage activities detected by electroencephalogram and elevated neuron-specific enolase/interleukin-6 concentrations in the cerebrospinal fluid suggested acute encephalopathy. MRI showed abnormalities in the bilateral thalami, cerebellum and brainstem. These abnormalities were protracted over a month. The biochemical and MRI characteristics of this case are different from any known type of encephalopathy, and may suggest a vulnerability of neurons expressing mutant SCN1A in the brain.

De novo mutations of voltage-gated sodium channel alphaII gene SCN2A in intractable epilepsies.

BACKGROUND: Mutations of voltage-gated sodium channel alpha(II) gene, SCN2A, have been described in a wide spectrum of epilepsies. While inherited SCN2A mutations have been identified in multiple mild epilepsy cases, a de novo SCN2A-R102X mutation, which we previously reported in a patient with sporadic intractable childhood localization-related epilepsy, remains unique. To validate the involvement of de novo SCN2A mutations in the etiology of intractable epilepsies, we sought to identify additional instances. METHODS: We performed mutational analyses on SCN2A in 116 patients with severe myoclonic epilepsy in infancy, infantile spasms, and other types of intractable childhood partial and generalized epilepsies and did whole-cell patch-clamp recordings on Na(v)1.2 channels containing identified mutations. RESULTS: We discovered 2 additional de novo SCN2A mutations. One mutation, SCN2A-E1211K, was identified in a patient with sporadic infantile spasms. SCN2A-E1211K produced channels with altered electrophysiologic properties compatible with both augmented (an approximately 18-mV hyperpolarizing shift in the voltage dependence of activation) and reduced (an approximately 22-mV hyperpolarizing shift in the voltage dependence of steady-state inactivation and a slowed recovery from inactivation) channel activities. The other de novo mutation, SCN2A-I1473M, was identified in a patient with sporadic neonatal epileptic encephalopathy. SCN2A-I1473M caused an approximately 14-mV hyperpolarizing shift in the voltage dependence of activation. CONCLUSIONS: The identified de novo mutations SCN2A-E1211K, -I1473M, and -R102X indicate that SCN2A is an etiologic candidate underlying a variety of intractable childhood epilepsies. The phenotypic variations among patients might be due to the different electrophysiologic properties of mutant channels.

Prognostic impact of PCR-based identification of isolated tumour cells in the peritoneal lavage fluid of gastric cancer patients who underwent a curative R0 resection.

Identification of cancer cells in the peritoneal cavity could influence therapy and outcome of gastric carcinoma patients. The objective of this study was to evaluate the clinical impact of the real-time quantitative polymerase chain reaction-(PCR) based identification of isolated tumour cells in the peritoneal lavage fluid of gastric carcinoma. The peritoneal lavage fluid of 116 patients with gastric cancer was sampled at laparotomy. After RNA extraction and reverse transcription, real-time quantitative PCR was performed using the primers and probes for carcinoembryonic antigen (CEA) and cytokeratin-20 (CK20). When either the CEA mRNA or CK20 mRNA level of the sample was over the cutoff value, the sample was determined to be PCR-positive. Forty-six (40%) of the 116 patients were PCR-positive and 30 (65%) of the 46 PCR-positive patients died as a result of recurrent peritoneal dissemination. The prognosis of the 46 PCR-positive patients was significantly (P<0.001) worse than that of 70 PCR-negative patients. Furthermore, in 80 of the cases with a curative R0 resection, 15 of the patients with PCR-positive findings had a significantly (P<0.001) poorer prognosis than the 65 PCR-negative patients. The prognosis of the PCR-positive patients was significantly poorer than that of the PCR-negative patients in the T3 (P<0.0001) and T4 (P=0.048) subgroups. In a multivariate analysis of the 80 cases with a curative R0 resection, the real-time quantitative RT-PCR (CEA and/or CK20) levels indicated that they were independent prognostic factors. The real-time quantitative RT-PCR analysis of the CEA and/or CK20 transcripts in the peritoneal lavage fluid is useful for predicting the peritoneal recurrence in patients who are undergoing a curative resection for gastric cancer.

Aberrant trafficking of a proteolipid protein in a mild Pelizaeus-Merzbacher disease.

Pelizaeus-Merzbacher disease (PMD) is a rare X-linked leukodystrophy caused by proteolipid protein 1 (PLP1) gene mutations. Previous studies indicated that proteolipid proteins (PLPs) with disease-associated mutations are misfolded and trapped in the endoplasmic reticulum (ER) during transportation to the cell surface, which eventually leads to oligodendrocyte cell death in PMD. Here we report a PMD patient with a very mild phenotype carrying a novel mutation (485G-->T) in exon 4 of the PLP1 gene that causes a Trp(162)Leu substitution in the protein. We also investigated intracellular trafficking of this mutant PLP in COS-7 cells. Transiently transfected mutant PLP(W162L) fused to an enhanced green fluorescent protein (EGFP) or a short peptide tag was not carried to the plasma membrane. However, in contrast to previous studies, this mutant PLP was not retained in the ER, indicating an escape of the newly translated protein from the quality control machinery. We also found that the mutant PLP accumulated in the nuclear envelope (NE) in a time-dependent manner. This mutant PLP, with its distribution outside the ER and a very mild phenotype, supports the idea that accumulation of misfolded mutant protein in the ER causes the severe phenotype of PMD.

Microarray expression analysis of gad mice implicates involvement of Parkinson's disease associated UCH-L1 in multiple metabolic pathways.

Parkinson's disease (PD) is thought to be caused by environmental and genetic factors. Mutations in four genes, alpha-synuclein, parkin, DJ-1, and UCH-L1, have been identified in autosomal inherited forms of PD. The pathogenetic cause for the loss of neuronal cells in PD patients, however, remains to be determined. Due to the rarity of mutations in humans with PD, the analysis of animal models might help to further gain insights into the pathogenesis of familial PD. For UCH-L1, deficiency has been described in gad mice leading to axonal degeneration and formation of spheroid bodies in nerve terminals. Here, we investigated the gene expression pattern of the brain of 3-month-old Uch-l1-deficient gracile axonal dystrophy (gad) mice by microarray analysis. A total of 146 genes were differentially regulated by at least a 1.4-fold change with 103 being up-regulated and 43 being down-regulated compared with age and sex matched wildtype littermate mice. The gene products with altered expression are involved in protein degradation, cell cycle, vesicle transport, cellular structure, signal transduction, and transcription regulation. Most of the genes were modestly regulated, which is in agreement that severe alteration of these pathways might be lethal. Among the genes most significantly down-regulated is the brain-derived neurotrophic factor which might be one aspect of the pathogenesis in gad mice. Interestingly, several subunits of the transcription factor CCAAT/enhancer binding protein are up-regulated, which plays a central role in most altered pathways.

Thoracoscopic internal mammary sentinel node biopsy for breast cancer.

Sentinel node (SN) biopsy has changed the management of breast cancer. This pilot study assessed the utility of lymphatic mapping and thoracoscopic SN biopsy for internal mammary node (IMN) staging. Forty-nine breast cancer patients underwent lymphatic mapping using 99mTc-tin colloid. Patients with IMSNs underwent thoracoscopic biopsy. Lymphoscintigraphy showed IMSNs in 15 of 49 cases (31%). The incidence of IMN drainage was relationed to age and tumor location; 50% of patients younger than age 40 and 43% with tumors located in inner quadrants had IMN drainage. The thoracoscopic procedure was performed in 11 of 15 patients, and 18 IMSNs were removed; the time of the procedure ranged from 20 to 60 min. No patients had complications from the procedure. Two of 11 patients (18%) had IMSN metastasis, and one of them had only IMN metastasis. Lymphatic mapping and the thoracoscopic approach were useful for IMSN biopsy. They may enable the physician to make an appropriate treatment decision for breast cancer.

Cloning, expression, and mapping of a mouse gene, Uchl4, highly homologous to human and mouse Uchl3.

Ubiquitin carboxyl-terminal hydrolases (UCHs) are implicated in the proteolytic processing of polymeric ubiquitin. We have isolated a novel mouse gene for ubiquitin carboxyl-terminal hydrolase isozyme L4. The gene named Uchl4 encodes a novel member of the family of ubiquitin carboxyl-terminal hydrolases (UCHs) whose predicted amino acid sequence shows 95% identity to mouse UCH-L3 and 94% identity to human UCH-L3. Genomic structure, chromosome localization, and expression pattern of Uchl3 and Uchl4 were characterized in the mouse. Both Uchl3 and Uchl4 were expressed in various tissues examined; however, expression level was quite lower in Uchl4. While Uchl3 consists of at least 9 exons spanning about 12 kb, Uchl4 was an intronless gene with a size of about 2 kb. By PCR-based analysis with T31 radiation hybrid mapping panel, Uchl3 and Uchl4 were mapped on mouse chromosome 9 and 14, respectively.

[Perspectives on postgenome medicine: Neurodegenerative disease].

The genes of the majority neurodegenerative disorders have been identified for the past decade. Diseases of early onset are usually transmitted as autosomal recessive trait and caused by the deficiency of the gene products, becoming good candidates for gene or protein transfers. Late onset diseases are usually transmitted dominantly where the gains of function by the mutant gene accumulate into specific lesion. The pathophysiology following gene mutation need to be clarified for the therapeutic approach. Recent progresses on neurodegenerative mechanism have specified crucial targets for the treatments. Stimulation to intrinsic mechanisms, i.e., chaperon, ubiquitin-proteasome system and stress response in endoplasmic reticulum and/or antagonize the toxic cascade by caspases, mitochondria insufficiency are argued as therapeutic targets, hoping that in this decade we can propose effective therapies for these devastating disorders.

Dissection of receptor folding and ligand-binding property with functional minireceptors of LDL receptor-related protein.

The LDL receptor-related protein (LRP) is a large, multifunctional endocytic receptor that binds and endocytoses a variety of structurally and functionally distinct ligands. LRP contains four putative ligand-binding domains. However, only domains II, III and IV, but not domain I, bind the receptor-associated protein (RAP), a molecular chaperone and universal antagonist for LRP. In order to dissect the function of RAP in LRP folding and to examine the ligand-binding properties of LRP, we generated LRP minireceptors that represent each of the four putative ligand-binding domains (termed mLRP1, mLRP2, mLRP3 and mLRP4, respectively). We found that proper folding and trafficking of mLRP2, mLRP3, mLRP4, but not mLRP1, is facilitated by coexpression of RAP. When these mLRPs were stably expressed in Chinese Hamster Ovary cells that lack the endogenous LRP, we found that each of these receptors was processed and traffics through the secretory pathway. Cell surface expression of these minireceptors was quantitatively examined by flow cytometric analyses. Using these minireceptor cell lines to map the ligand-binding domains, we found that although the majority of LRP ligands bind to both domain II and domain IV, Pseudomonas exotoxin A utilizes only domain IV for its binding to LRP. We conclude that while domains II and IV of LRP share many ligand-binding properties, each of the putative ligand-binding domains of LRP is unique in its contribution to ligand binding.