MATERIALS AND METHODS: 52 healthy volunteers were scanned in a 16-slice MDCT, and the volume of 104 sets of carpal bones was measured using a Syngo workstation (Both CT and workstation-Siemens Healthcare, Erlangen, Germany).
RESULTS: Male carpal bones were of higher volume compared to the female carpal bones (p<0.001). Area under the curve (AUC) assessment of responder-operator characteristics curves showed that the trapezium bone was best able to predict sex with an AUC of 0.986. At a trapezium bone volume of ⩾1.94cm(3), there was a 93.5% probability that the subject was male. Binary logistic regression analysis found that the highest accuracy was derived using the pisiform, trapezium and capitate bones. There was a strong relationship between sex prediction and grouping of the carpal bone volumes (Nagelkerke R(2)=0.923) with an overall prediction accuracy of 97%.
CONCLUSION: All 8 carpal bones exhibit sexual dimorphism to varying degrees. A binary regression analysis combining the 5 carpal bones with the highest predictive values for sex produces an accurate predictive model.
RESULTS: A bulk segregant analysis (BSA) version of double-digest restriction-site associated DNA sequencing (BSA-ddRADseq) was developed and used to detect and position sex-linked single nucleotide polymorphism (SNP) markers in 19 families from the GIFT strain breeding nucleus and two Stirling families as controls (a single XY locus had been previously mapped to LG1 in the latter). About 1500 SNPs per family were detected across the genome. Phenotypic sex in Stirling families showed strong association with LG1, whereas only SNPs located in LG23 showed clear association with sex in the majority of the GIFT families. No other genomic regions linked to sex determination were apparent. This region was validated using a series of LG23-specific DNA markers (five SNPs with highest association to sex from this study, the LG23 sex-associated microsatellite UNH898 and ARO172, and the recently isolated amhy marker for individual fish (n = 284).
CONCLUSIONS: Perhaps surprisingly given its multiple origins, sex determination in the GIFT strain breeding nucleus was associated only with a locus in LG23. BSA-ddRADseq allowed cost-effective analysis of multiple families, strengthening this conclusion. This technique has potential to be applied to other complex traits. The sex-linked SNP markers identified will be useful for potential marker-assisted selection (MAS) to control sex-ratio in GIFT tilapia to suppress unwanted reproduction during growout.
CASE PRESENTATION: A 25-year-old super morbidly obese female (body mass index = 55 kg/meter2) presented with worsening shortness of breath. For MV, pairing of a 6 mm (mm) diameter ETT to accommodate the patient's vocal cord edema, with a CSS not designed to maintain a clean catheter tip, precipitated ETT blockage and respiratory acidosis. Replacement of these devices with a 6.5 mm ETT and a CSS designed to keep the catheter tip clean resolved the complications. After use of the different ETT and CSS for approximately one week, the patient was discharged to home.
DISCUSSION: The clean-tip catheter CSS enabled a more patent airway than its counterpart device that did not have this feature. Use of a clean-tip catheter CSS was an important care development for this patient, because this individual's super morbidly obese condition minimized tolerance for MV complications that would exacerbate her pre-existing tenuous respiratory health status.
CONCLUSION: Special attention should be given to the choices of ETT size and CSS to manage super morbidly obese patients who have a history of difficult airway access.