Segregation analysis of idiopathic talipes equinovarus in a Texan population

“Idiopathic” talipes equinovarus (ITEV) is a nonsyndromal congenital anomaly of one or both feet. Casting and surgery are often necessary to obtain correct foot alignment. In spite of treatment, residual deformities of the feet occur and calf muscles may be hypoplastic. The cause of ITEV is unknown but genetic factors have been postulated. Complex segregation analysis was performed on 173 ITEV families including 93 Caucasian and 48 Hispanic families. The recessive mixed model was the best fitting model and no differences were found based on ethnicity. These results confirm previous studies suggesting that there is a genetic component to the development of ITEV. Am. J. Med. Genet. 79:97–102, 1998. © 1998 Wiley-Liss, Inc.     

Real-Time Genomic Surveillance during the 2021 Re-Emergence of the Yellow Fever Virus in Rio Grande do Sul State,Brazil

The 2021 re-emergence of yellow fever in non-human primates in the state of Rio Grande do Sul (RS), southernmost Brazil, resulted in the death of many howler monkeys (genus Alouatta) and led the state to declare a Public Health Emergency of State Importance, despite no human cases reported. In this study, near-complete genomes of yellow fever virus (YFV) recovered from the outbreak were sequenced and examined aiming at a better understanding of the phylogenetic relationships and the spatio-temporal dynamics of the virus distribution. Our results suggest that the most likely sequence of events involved the reintroduction of YFV from the state of São Paulo to RS through the states of Paraná and Santa Catarina, by the end of 2020. These findings reinforce the role of genomic surveillance in determining the pathways of distribution of the virus and in providing references for the implementation of preventive measures for populations in high risk areas.     

Recombinagenic activity of integerrimine,a pyrrolizidine alkaloid from Senecio brasiliensis,in somatic cells of Drosophila melanogaster

Integerrimine (ITR), a pyrrolizidine alkaloid from Senecio brasiliensis, was tested for genotoxicity using the wing somatic mutation and recombination test (SMART) in Drosophila melanogaster. The compound was administered by chronic feeding (48 hours) of 3-day-old larvae. Two different crosses involving the markers flare (flr) and multiple wing hairs (mwh) were used, that is, the standard (ST) cross and the high bioactivation (HB) cross, which has a high cytochrome P450-dependent bioactivation capacity. In both crosses, the wings of two types of progeny were analyzed, that is, inversion-free marker heterozygotes and balancer heterozygotes carrying multiple inversions. ITR was found to be equally potent in inducing spots in a dose-related manner in the marker heterozygotes of both crosses. This indicates that the bioactivation capacity present in larvae of the ST cross is sufficient to reveal the genotoxic activity of ITR. In the balancer heterozygotes of both crosses, where all recombinational events are eliminated due to the inversions, the frequencies of induced spots were considerably reduced which documents the recombinagenic activity of ITR. Linear regression analysis of the dose response relationships for both genotypes shows that 85% to 90% of the wing spots are due to mitotic recombination. Environ. Mol. Mutagen 29:91–97, 1997 © 1997 Wiley-Liss, Inc.     

Comparison of model-free linkage mapping strategies for the study of a complex trait

We compared several strategies for identifying and estimating effects from a genetic locus in the etiology of a complex trait. For our analyses we used data from simulated trait 1 and chromosome 5. Results from analysis of the first 20 replicates showed that a components of variance test provided considerably better power for identifying linkage than tests that consider pair differences. We also compared the power from constructing tests with a single marker, an approximate method using five markers jointly, or a multipoint analysis using all 25 markers on chromosome 5 jointly. Results from this analysis showed substantially better power when all markers were jointly used in the analysis. Results from considering all replicates showed that all methods of estimation provided maximal test statistics at the correct marker position, but the components of variance procedure provided more power to detect the correct position than other methods. © 1997 Wiley-Liss, Inc.     

Can a gas phase contact ion pair containing a hydrocarbon carbocation be formed in the ground state?

So far, no conclusive evidence of a ground-state contact ion-pair containing a hydrocarbon carbocation has been given in the gas phase. Due to the very high stability of the 1,2:4,5-dibenzotropylium (or dibenzo[a,d]tropylium) carbocation, we suggest (supported by DFT and MP2 calculations) the formation of a contact ion pair between this carbocation and chloride, occurring during the reaction between 1,2:4,5-dibenzotropyl (also named dibenzo[a,d]tropyl or dibenzo[a,d]cycloheptenyl) radical and chlorine atom at very low temperatures, through the harpoon mechanism. This is the first modeling study to find computational evidence for the possibility of a gas-phase contact ion pair (containing a hydrocarbon carbocation) formed in the ground state. Identification of this metastable species can be carried out by trapping it in He nanodroplets, along with infrared laser spectroscopy routinely coupled with this technique.

So far, no conclusive evidence of a ground-state contact ion-pair containing a hydrocarbon carbocation has been given in the gas phase.     

Superconducting Properties and Electron Scattering Mechanisms in a Nb Film with a Single Weak-Link Excavated by Focused Ion Beam

Granularity is one of the main features restricting the maximum current which a superconductor can carry without losses, persisting as an important research topic when applications are concerned. To directly observe its effects on a typical thin superconducting specimen, we have modeled the simplest possible granular system by fabricating a single artificial weak-link in the center of a high-quality Nb film using the focused ion beam technique. Then, its microstructural, magnetic, and electric properties in both normal and superconducting states were studied. AC susceptibility, DC magnetization, and magneto-transport measurements reveal well-known granularity signatures and how they negatively affect superconductivity. Moreover, we also investigate the normal state electron scattering mechanisms in the Boltzmann theory framework. The results clearly demonstrate the effect of the milling technique, giving rise to an additional quadratic-in-temperature contribution to the usual cubic-in-temperature sd band scattering for the Nb film. Finally, by analyzing samples with varying density of incorporated defects, the emergence of the additional contribution is correlated to a decrease in their critical temperature, in agreement with recent theoretical results.     

EGFR exon mutation distribution and outcome in non-small-cell lung cancer: a Portuguese retrospective study

Epidermal growth factor receptor (EGFR) mutations play a predictive role in advanced stages of non-small-cell lung cancer (NSCLC) patients. We conducted this study in order to assess EGFR status in a Portuguese population and its role in NSCLC patients' outcomes. Patients were submitted to EGFR assessment by high-resolution melting and/or direct sequencing. Kaplan?CMeier curve was used to assess overall survival and progression-free survival (PFS). Two hundred forty eight out of 322 participants were assessed for EGFR status. Forty-two patients (16.9?%) presented EGFR-mutated status: one patient (2.4?%) presented exon 18; 21 patients (50?%), exon 19; one patient (2.4?%), exon 20; and 18 patients (45.2?%), exon 21 mutations, p?<?0.001. PFS was not assessed (n.a.) for patient with exon 18 mutation, and for the other patients with mutations, it was 7?months (3.96?C10.03) (exon 19), <1?month (exon 20), and 7?months (0?C14.2) (exon 21) (p?=?0.027). Overall survival (OS) was 11?months (exon 18), 11?months (1?C18) (exon 19), 1?month (exon 20), and 7.5?months (2?C70) (exon 21) (p?=?n.a). This study suggests that the EGFR mutation is herein observed in a higher proportion than expected for a Caucasian population, and OS is a little less than that published in the literature.