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Swarm robotics system (SRS) is a type of artifact that employs multiple robots to work together in a coordinated way, inspired by the self-organizing behavior of social insects such as ants and bees. SRSs are known for their robustness, flexibility, and scalability. This study focuses on evolutionary robotics (ER) which uses artificial neural networks (ANNs) as controllers to operate autonomous robots. In traditional ER research, SRSs were often composed of teams of homogeneous robots, each of which is controlled by a single ANN. In contrast, this study focuses on the implementation of ER in a heterogeneous SRS. To evaluate our approach, we present the concept of employing multiple controllers for sub-teams in a swarm. Heterogeneity was achieved using different controllers for the same physical bodies. We simulated a cooperative transport task, in which the performance of heterogeneity was superior because the two ANN controllers were able to express a variety of behaviors as an entire swarm. Additionally, this study investigated how well the three types of parental selection methods of the heterogeneous approach, can help to optimize the performance of the swarm. [ABSTRACT FROM AUTHOR]

Context: X-linked hypophosphatemic rickets/osteomalacia (XLH), autosomal dominant and recessive hypophosphatemic rickets/osteomalacia (ADHR and ARHR) share common clinical features including high fibroblast growth factor 23 (FGF23) levels. These diseases are caused by mutations in phosphate regulating endopeptidase homolog, X-linked (PHEX), FGF23, and dentin matrix acidic phosphoprotein 1 (DMP1) gene respectively. It remains unclear whether these diseases can be clinically discriminated. Objective: To clarify the underlying mechanism of patients with hypophosphatemic rickets whose parents showed no physical findings suggesting rickets. Design and patients: The proband is a 39-year-old woman. She and her 37-year-old brother show the same clinical features such as bowing of legs together with hypophosphatemia (sister: P 1.8 mg/dl, brother: P 1.6 mg/dl) and high FGF23 levels (sister: 542 pg/ml, brother: 96 pg/ml). Physical findings of their parents are normal and ARHR was suspected. Results: Sequencing of all coding exons and exon-intron junctions of DMP1 and FGF23 genes showed no mutation. Subsequent analysis revealed that there is a deletion of 52 143 bp including exons 1-3 in PHEX gene in the brother. His sister was found to be a heterozygote for the same deletion indicating that they are suffering from XLH. The same deletion was detected in the mother. However, the amount of the wild-type allele was more and that of the mutant one was less in genomic DNA from the mother compared with those from the sister. Single nucleotide polymorphism (SNP) analysis indicated that the mother has three kinds of PHEX alleles suggesting a somatic mosaicism. Conclusion: Careful genetic analysis is mandatory for correct differential diagnosis of hypophosphatemic rickets with high FGF23 levels. [ABSTRACT FROM AUTHOR]

Objective: This study analyzed the mutation of 21-hydroxylase deficiency (21-OHD) in 36 unrelated Japanese patients with congenital adrenal hyperplasia (CAH). Methods: All the exons of the functional CYP21 gene (CYP21A2) were analyzed by polymerase chain reaction (PCR) and PCR direct sequencing. Results: Apparent gene deletions and conversions were present in 23.6% of the 72 CAH alleles, in which the most frequent mutation was the IVS2-13 A/C>G (27.8%), followed by I172N (26.3%), consistent with the frequencies reported for other countries. Previously described mutations were not present in three unrelated cases. Sequence analysis of the complete functional CYP21A2 gene revealed three, not yet described mutations that represent a common pseudogene sequence. These three putative novel mutations are located in exon 1 (M1I), in exon 5 (1210–1211insT), and in exon 3 (R124H). Conclusions: In this study, we have identified three putative novel mutations. It remains to be determined whether these three mutations are responsible for the significant number of as yet uncharacterized CAH patients in Japan. Copyright © 2004 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Gain-of-function mutations of the extracellular calcium (Ca[sup 2+]e)-sensing receptor (CaR) have been identified in patients with familial and sporadic hypercalciuric hypocalcaemia. We describe a patient with sporadic severe hypercalciuric hypocalcaemia with undetectable or very low levels of serum parathyroid hormone, carrying a de novo heterozygous missense mutation (F821L), localized in the sixth transmembrane domain of CaR. Analysis of in vitro functional properties of the mutant receptor to measure Ca[sup 2+]e-evoked changes in intracellular Ca[sup 2+] revealed a leftward shift in the concentration-response curve for the mutant compared to wild-type receptor. Conclusion:the F821L mutation is therefore a novel gain-of-function mutation which can cause severe hypoparathyroidism. Thiazide diuretics lowered urinary calcium excretion of the patient treated with calcium supplementation and 1α-hydroxyvitamin D[sub 3.] [ABSTRACT FROM AUTHOR]

We treated an extremely tall 13-year-old girl with a growth hormone (GH)-secreting macroadenoma and GH levels of 120–495 ng/ml with a combination of preoperative octreotide infusion, surgery and postoperative octreotide infusion plus estrogen, which resulted in reduced tumor size prior to surgery, reduced GH levels and completely suppressed growth after surgery. 20K GH is produced by alternative splicing of 22K GH mRNA and the ratio of 20K GH to 22K GH is within a small range in the normal population and high in a GH-secreting tumor. The 20K/22K GH ratio in this patient was persistently elevated during each phase of the treatment and may serve as a sensitive index of tumor-derived GH secretion.Copyright © 2000 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]