Mutations in SDR9C7 gene encoding an enzyme for vitamin A metabolism underlie autosomal recessive congenital ichthyosis

Autosomal recessive congenital ichthyosis (ARCI) is a heterogeneous group of hereditary skin disorder characterized by an aberrant cornification of the epidermis. ARCI is classified into a total of 11 subtypes (ARCI1-ARCI11) based on their causative genes or loci. Of these, the causative gene for only ARCI7 has not been identified, while it was previously mapped on chromosome 12p11.2-q13.1. In this study, we performed genetic analyses for three Lebanese families with ARCI, and successfully determined the linkage interval to 9.47 Mb region on chromosome 12q13.13-q14.1, which was unexpectedly outside of the ARCI7 locus. Whole-exome sequencing and the subsequent Sanger sequencing led to the identification of missense mutations in short chain dehydrogenase/reductase family 9C, member 7 (SDR9C7) gene on chromosome 12q13.3, i.e. two families shared an identical homozygous mutation c.599T > C (p.Ile200Thr) and one family had another homozygous mutation c.214C > T (p.Arg72Trp). In cultured cells, expression of both the mutant SDR9C7 proteins was markedly reduced as compared to wild-type protein, suggesting that the mutations severely affected a stability of the protein. In normal human skin, the SDR9C7 was abundantly expressed in granular and cornified layers of the epidermis. By contrast, in a patient’s skin, its expression in the cornified layer was significantly decreased. It has previously been reported that SDR9C7 is an enzyme to convert retinal into retinol. Therefore, our study not only adds a new gene responsible for ARCI, but also further suggests a potential role of vitamin A metabolism in terminal differentiation of the epidermis in humans.

Novel splice site mutation in the LIPH gene in a patient with autosomal recessive woolly hair/hypotrichosis: Case report and published work review

Autosomal recessive woolly hair is a relatively rare hereditary hair disorder characterized by sparse, short, curly hair. This condition is known to be caused by mutations in the LIPH gene, LPAR6 gene or KRT25 gene. In the Japanese population, most patients with autosomal recessive woolly hair carry one of two founder mutations in the LIPH gene, c.736T>A (p.Cys246Ser) or c.742C>A (p.His248Asn). However, occasionally, individuals with this condition carry compound heterozygous mutations, typically one founder mutation and another mutation. In this study, we describe a patient with a compound heterozygous mutation in the LIPH gene at c.736T>A and c.1095-3C>G. The latter mutation created a novel splice site. This was the fourth splice site mutation to be described in the LIPH gene. Furthermore, we performed an in vitro transcription assay in cultured cells, and demonstrated that the c.1095-3C>G mutation led to a frame-shift, which created a premature termination codon at the protein level (p.Glu366Ilefs*7). Finally, we summarized the mutations previously reported for the LIPH gene. Our findings provide further clues as to the molecular basis of autosomal recessive woolly hair.

Comparison of MR Imaging and Dual-Energy CT for the Evaluation of Cartilage Invasion by Laryngeal and Hypopharyngeal Squamous Cell Carcinoma

BACKGROUND AND PURPOSE

Dual-energy CT can distinguish iodine-enhanced tumors from nonossified cartilage and has been investigated for evaluating cartilage invasion in patients with laryngeal and hypopharyngeal squamous cell carcinomas. In this study, we compared the diagnostic accuracy of MR imaging and of a combination of weighted-average and iodine overlay dual-energy CT images in detecting cartilage invasion by laryngeal and hypopharyngeal squamous cell carcinomas, in particular thyroid cartilage invasion.

MATERIALS AND METHODS

Fifty-five consecutive patients who underwent 3T MR imaging and 128-slice dual-energy CT for preoperative initial staging of laryngeal or hypopharyngeal squamous cell carcinomas were included. Two blinded observers evaluated laryngeal cartilage invasion on MR imaging and dual-energy CT using a combination of weighted-average and iodine-overlay images. Pathologic findings of surgically resected specimens were used as the reference standard for evaluating sensitivity, specificity, and the areas under the receiver operating characteristic curve of both modalities for cartilage invasion by each type of cartilage and for all cartilages together. Sensitivity and specificity were compared using the McNemar test and generalized linear mixed models.

RESULTS

Dual-energy CT showed higher specificity than MR imaging for diagnosing all cartilage together (84% for MR imaging versus 98% for dual-energy CT, P < .004) and for thyroid cartilage (64% versus 100%, P < .001), with a similar average area under the curve (0.94 versus 0.95, P = .70). The sensitivity did not differ significantly for all cartilages together (97% versus 81%, P = .16) and for thyroid cartilage (100% versus 89%, P = .50), though there was a trend toward increased sensitivity with MR imaging.

CONCLUSIONS

Dual-energy CT showed higher specificity and acceptable sensitivity in diagnosing laryngeal cartilage invasion compared with MR imaging.

<i>Hexapleomera urashima</i> sp. nov. (Crustacea: Tanaidacea), a tanaidid epibiotic on loggerhead sea turtles at Yakushima Island, Japan

We describe Hexapleomera urashima sp. nov. from the carapaces of loggerhead sea turtles (Caretta caretta) on Yakushi-ma Island, southwestern Japan, the primary nesting site for the North Pacific population of this turtle. Hexapleomera urashima closely resembles H. edgari Bamber collected from Australian loggerheads (South Pacific population), sharing a uropod with four articles and maxillipedal endites with distal spiniform setae, but differs in having the maxillipedal coxa with two simple setae, the maxillipedal endite with two tiny dorsosubdistal and two distal spiniform setae, the labial palp fused to the outer lobe of the labium, and the basal article of pleopod 3 without inner setae. Several characters (e.g., size or presence/absence of a dorsal triangular process on the male fixed finger; number of inner setae on the pleopodal endopod), assumed to be diagnostic for species in Hexapleomera, actually vary within H. urashima, indicating that reassessment of species diagnoses is warranted. Hexapleomera urashima showed two COI haplotypes differing by one substitution, but separated from representatives of four other genera by 32.2-48.4% K2P distance. Indices of saturation substitution indicated that COI is not useful for phylogeny reconstruction within Tanaididae.

Outcomes following autologous hematopoietic stem cell transplant for patients with relapsed Wilms' tumor: a CIBMTR retrospective analysis

Despite the dramatic improvement in the overall survival for patients diagnosed with Wilms’ tumor (WT), the outcomes for those that experience relapse have remained disappointing. We describe the outcomes of 253 patients with relapsed WT who received high-dose chemotherapy (HDT) followed by autologous hematopoietic stem cell transplant (HCT) between 1990 and 2013, and reported to the Center for International Blood and Marrow Transplantation Research (CIBMTR). The 5-year estimates for event free survival (EFS) and overall survival (OS) were 36% (95% CI; 29 – 43%) and 45% (95% CI; 38 – 51%) respectively. Relapse of primary disease was the cause of death in 81% of the population. EFS, OS, relapse and transplant-related mortality (TRM) showed no significant differences when broken down by disease status at transplant, time from diagnosis to transplant, year of transplant or conditioning regimen. Our data suggest that HDT followed by autologous HCT for relapsed WT is well tolerated and outcomes are similar to those reported in the literature. Since attempts to conduct a randomized trial comparing maintenance chemotherapy with consolidation versus high-dose chemotherapy followed by stem cell transplant have failed, one should balance the potential benefits with the yet unknown long-term risks. Since disease recurrence continues to be the most common cause of death, future research should focus on the development of consolidation therapies for those patients achieving complete response to therapy.

Maneuvering Support System for an Amphibian Vehicle – Warning Display to Prevent Rough Maneuvers –

[abstFig src='/00290003/14.jpg' width='300' text='Amphibian vehicle maneuvering simulator' ] This study proposes a maneuvering support system for an amphibian vehicle by applying a nonlinear state feedback control law for vehicle trajectory control. We consider that the vehicle should not drift sideways for good driving performance. To derive a nonlinear state feedback control law, we have defined ‘Maneuvering Trajectory’ as an additional reference trajectory that is generated by the driver’s maneuver. We have constructed a Lyapunov-like function for the trajectory control system. In this paper, we construct a vehicle-maneuvering simulator and set a clockwise circular reference trajectory. The efficiency of the proposed maneuvering support system is shown in the maneuvering simulations. We consider the case where the propulsive forces of the vehicle have limited influence on maneuverability. A new warning display system is proposed so that the driver can recognize if his or her maneuver is not suitable. Then, we examine the feasibility of the proposed warning display system through several simulations.

A novel mutation in the RSPO4 gene in a patient with autosomal recessive anonychia

The Wnt signalling pathway is a major pathway involved in the embryogenic development of the various organs of the body. Appropriate signalling in this pathway relies on the proper functioning of several proteins including the R-spondin family of proteins. Deactivating mutations in R-spondin 4 are associated with anonychia. We present the case of a 26-year-old man presenting with anonychia of the 20 nails, which had been present since birth. Using genetic studies, we identified a novel nonsense mutation, c.164-165TC>AA, characterized by two consecutive mismatch bases. To our knowledge, this mutation is the first to be reported in R-spondin 4 in a Lebanese population. Evaluating new patients with anonychia provides fruitful clinical and molecular findings.