Aquatic insect community structure revealed by eDNA metabarcoding derives indices for environmental assessment.

Environmental DNA (eDNA) analysis provides an efficient and objective approach for monitoring and assessing ecological status; however, studies on the eDNA of aquatic insects, such as Ephemeroptera, Plecoptera, and Trichoptera (EPT), are limited despite its potential as a useful indicator of river health. Here, we investigated the community structures of aquatic insects using eDNA and evaluated the applicability of eDNA data for calculating assessment indices. Field surveys were conducted to sample river water for eDNA at six locations from upstream to downstream of two rivers in Japan in July and November 2016. Simultaneously, aquatic insects were collected using the traditional Surber net survey method. The communities of aquatic insects were revealed using eDNA by targeting the cytochrome oxidase subunit I gene in mitochondrial DNA via metabarcoding analyses. As a result, the eDNA revealed 63 families and 75 genera of aquatic insects, which was double than that detected by the Surber net survey (especially for families in Diptera and Hemiptera). The seasonal differences of communities were distinguished by both the eDNA and Surber net survey data. Furthermore, the total nitrogen concentration, a surrogate of organic pollution, showed positive correlations with biotic environmental assessment indices (i.e., EPT index and Chironomidae index) calculated using eDNA at the genus-level resolution but the indices calculated using the Surber net survey data. Our results demonstrated that eDNA analysis with higher taxonomic resolution can provide as a more sensitive environmental assessment index than the traditional method that requires biotic samples.

Transfer of cyanobacterial carbon to a higher trophic-level fish community in a eutrophic lake food web: fatty acid and stable isotope analyses.

The dietary utilization of cyanobacterial carbon by fish communities is poorly understood. We examined the transfer of cyanobacterial carbon to fish in a eutrophic lake using fatty acid biomarkers and measuring the stable carbon isotope ratios of fatty acid and bulk nitrogen. We collected five species of fish (Hypomesus nipponensis, Carassius sp., Cyprinus carpio, Tridentiger brevispinis, and Gymnogobius castaneus) as well as the seston from June to November 2016 from Lake Hachiro, Japan. Cyanobacterial blooms were observed from August to October. From June to August, cyanobacterial fatty acid biomarkers (18:2ω6 and 18:3ω3) accounted for only 1.4-4.3% of total fatty acids in these fish species, indicating a low contribution of cyanobacteria to fish diets during this period. However, the contribution of the cyanobacterial fatty acid biomarkers in these fish species increased sharply in September (10.5-17.1%), except in second-year H. nipponensis. In September, the stable carbon isotope ratios of 18:3ω3 in these fish species were almost equivalent to those in the seston, which was primarily composed of cyanobacteria. The trophic positions of the collected fish species ranged from 1.6 to 3.4, based on their stable nitrogen isotope values, indicating that some fish ingested cyanobacteria directly, while others acquired cyanobacteria indirectly, through the food chain. These findings indicate that cyanobacterial carbon is transferred up the food chain in eutrophic lake ecosystems with cyanobacterial blooms.

The Distribution and Cellular Lineages of XX and XY Cells in Gonads Associated with Ovotesticular Disorder of Sexual Development.

Individuals with a 46,XX/46,XY karyotype are categorized as ovotesticular disorder of sexual development (ODSD) and have gonads with either an ovary on one side and a testis on the other side or a mixed ovotestis. To examine the distribution of 46,XX and 46,XY cells in gonads of 3 patients with ODSD, FISH for X and Y chromosomes and immunohistochemistry for SOX9 and FOXL2 were carried out. FISH analysis showed that XX signals were present in Sertoli cells in the seminiferous tubules, while cells containing Y signals were seen in epithelia of ovarian follicles. The immunolabeling of SOX9 and FOXL2 in the seminiferous tubules and ovarian follicles was mutually exclusive, irrespective of the presence of reversed sex chromosomes. We therefore suggest that the fate of individual gonadal epithelial cells is determined not only by the sex chromosomes but also by local environmental factors.

Identification of X monosomy cells from a gonad of mixed gonadal dysgenesis with a 46,XY karyotype: case report.

Mixed gonadal dysgenesis (MGD) is a disorder of sexual development that typically has a mosaic 45,X/46,XY karyotype. A 1-year-old infant with 46,XY identified by peripheral blood karyotype demonstrated clinical manifestations and gonadal pathologic features of MGD. Fluorescence in situ hybridization (FISH) for X and Y chromosomes and immunofluorescence for SRY along with testicular and ovarian lineage markers SOX9 and FOXL2, respectively, were performed on paraffin sections from the gonad to ascertain the somatic mosaic state for 45,X monosomy and 46,XY cells. The gonad consisted of cells with X and XY signals, which were further quantified in comparison with a normal control testis by a digital image analysis program. The average percentages of 45,X cells of this patient's gonad and a control testis were 39.0% and 5.7%, respectively (χ2 test, P < 0.001). SRY expression was absent in approximately 10% of precursor granulosa cells (FOXL2 positive) and precursor Sertoli/granulosa cells (both SOX9 and FOXL2 positive) within gonadoblastomas, confirming the involvement of 45,X cells. A combination of analysis of FISH and immunofluorescence for SRY in the gonadal tissue could identify 45,X cells in MGD with 46,XY.

Characteristic testicular histology is useful for the identification of NR5A1 gene mutations in prepubertal 46,XY patients.

BACKGROUND: Individuals with NR5A1 mutations encoding steroidogenic factor-1 (SF1) develop a phenotypically broad range of disorders of sexual development (DSD). Based on a literature review, we noted that hypoplastic seminiferous tubules and the emergence of Leydig cells with vacuolar cytoplasms are seen predominantly in the majority of individuals with NR5A1 mutations. AIM: The aim of this study was to address whether the histopathological characteristics of the testis can be a biomarker for 46,XY individuals with NR5A1 mutations. DESIGN: In order to ascertain whether or not the histological features were the characteristics of NR5A1 mutations, we screened the testicular histology of 242 patients with 46,XY DSD and then subsequently assessed NR5A1 mutations. RESULT: Of 242 patients with 46,XY DSD, 6 patients matched histological testicular features: a reduced number of thin seminiferous tubules and focal aggregations of Leydig cells that contained cytoplasmic lipid droplets. All 6 patients had NR5A1 mutations. These histological features were distinct from those of other DSD. Thus, this unique testicular histology is useful for identifying NR5A1 mutations in 46,XY patients with DSD before puberty.

The presence of N(ε)-(Carboxymethyl) lysine in the human epidermis.

It is well known that advanced glycation end products (AGEs) are formed in long-lived dermal proteins such as collagen, and that their formation is related to skin aging. To examine the distribution of AGEs in skin tissue, we performed immunofluorescence studies on the human skin using an anti-AGEs antibody. Interestingly, AGEs signals were observed not only in the dermis but also in the epidermis. The objectives of this study were to confirm the presence of N(ε)-(Carboxymethyl) lysine (CML), an AGE structure, in the epidermis and to characterize the CML-modified proteins. The presence of CML in the stratum corneum (SC) was examined using liquid chromatography-electrospray ionization time-of-flight mass spectrometry. Concordance between the retention times of a compound in the SC hydrolysate and authentic CML, as well as with the specific mass transition of CML, was detected. This result showed that CML is present in the epidermis. In order to characterize the CML-modified proteins in the epidermis, protein samples extracted from the SC were analyzed using two-dimensional electrophoresis followed by an amino acid sequence analysis. The clarified peptide sequences covered approximately 27% of the amino acid sequences of cytokeratin 10 (K10). In the immunoblotting experiment following the two-dimensional electrophoresis, where protein samples extracted from whole epidermis were used, the position of the major CML-positive spots corresponded to those of K10. Taken together these results showed that CML is present in the human epidermis, and suggest that K10 is one of the target molecules for CML modification in the epidermis.

The clinical characteristics of vitamin D deficiency in childhood: a systematic literature review of Japanese patients.

To describe the characteristics of children with vitamin D deficiency, we reviewed the reports of vitamin D deficiency among Japanese children that were published between 1989 and 2008. We identified 25 patients with vitamin D deficiency in 9 published studies and evaluated their clinical characteristics together with those of 3 patients we recently treated. The patients were distributed in two distinct age groups at diagnosis: < 1 year old and > or = 1 year old. The main symptom of the < 1 year old age group was hypocalcemic convulsions and that of the > or = 1 year old age group was bowed legs. Serum calcium, intact PTH, and 1,25(OH)2D levels were significantly lower in the < 1 year age group than in the > or = 1 year age group. It would be useful to find and make early interventions in cases of children at a high-risk of vitamin D deficiency.

A novel nonsense mutation of the mineralocorticoid receptor gene in the renal form of pseudohypoaldosteronism type 1.

Pseudohypoaldosteronism type 1 (PHA1) is a rare congenital disease characterized by salt loss resistant to mineralocorticoids. Most patients are identified by failure to thrive or poor weight gain in early infancy. Plasma renin activity and aldosterone are markedly elevated. PHA1 is caused by mutations in genes encoding either subunits of the amiloride-sensitive epithelial sodium channel (ENaC) or mineralocorticoid receptor (MR) inherited in an autosomal recessive or dominant form, respectively. Patients with the autosomal dominant form of PHA1 show gradual clinical improvement with advancing age; however, the reason for this remains unclear. We report the renal form of PHA1 in a Japanese family. Polymerase chain reaction and direct sequencing revealed a heterozygous nonsense mutation changing codon 861 Arg (CGA) to stop (TGA) in the index patient. Segregation analysis revealed an identical mutation in the patient's father and older sister. Inheritance in this case is assumed to be of the autosomal dominant type.

Simultaneous onset of type 1 diabetes in monozygotic twins younger than 1 year.

This report describes type 1 insulin deficient diabetes mellitus (IDDM) arising in identical twins aged under one year. One twin presented with symptoms and was diagnosed with type 1 IDDM; the diagnosis of type 1 IDDM was simultaneously made in the second twin without clinical symptoms. Both twins were positive for anti-GAD (glutamic acid decarboxylase) antibody at first, and then positive for islet cell antibodies. Interestingly, the twins have four susceptible HLA DR and DQ genes together that are usually recognized separately in IDDM patients in Japan.

Thalidomide for treatment of intestinal involvement of juvenile-onset Behçet disease.

BACKGROUND: Thalidomide has been identified and its anti-inflammatory and immunomodulatory properties clarified. This report expands our report of 2 entero-Behçet disease children who developed significant steroid toxicity and improved dramatically with thalidomide. METHODS: We studied the effects of thalidomide in 7 juvenile-onset patients with severe, recurrent intestinal involvement of Behçet disease. Thalidomide was given at an initial dose of 2 mg/kg per day, and the dose was increased to 3 mg/kg per day if necessary (3 of 7 patients) or decreased to 1-0.5 mg/kg per day according to the responses to the drug. RESULTS: All 7 patients showed dramatic improvement in clinical symptoms with thalidomide therapy, and they successfully discontinued steroid therapy. Patients receiving thalidomide were monitored for prolonged neurotoxicity, and the treatment and a few side effects were well tolerated by all patients. CONCLUSIONS: Our results indicate that thalidomide can be an efficacious medication in appropriately selected patients with some inflammatory bowel diseases with many chances of success.

Recent changes in the trends of seasonal influenza outbreaks in the Nagano Prefectural area of Japan: an oseltamivir effect?

We carried out a study to assess the pharmacological role of oseltamivir in the regulation of influenza epidemics in Japan, examining data for the years 1998 to 2006 from Nagano Prefecture. Oseltamivir is effective for the treatment of influenza, and its use in Japan has increased in the 3 years from 2003 to 2006. We found that, in the Nagano Prefectural area, the peak in the number of influenza infections showed a deviation to later periods after the 2003 season. and after 2003, it also took a longer time to reach the end of the seasonal epidemics of influenza infections compared with data from 1998 to 2002. To prevent influenza outbreaks having a long duration, we believe that the period of isolation in patients receiving anti-influenza drugs has to be reconsidered.