Estrogen levels influence medullary bone quantity and density in female house finches and pine siskins.

Medullary bone, a non-structural osseous tissue, serves as a temporary storage site for calcium that is needed for eggshell production in a number of avian species. Previous research focusing primarily on domesticated species belonging to the Anseriformes, Galliformes, and Columbiformes has indicated that rising estrogen levels are a key signal stimulating medullary bone formation; Passeriformes (which constitute over half of extant bird species and are generally small) have received little attention. In the current study, we examined the influence of estrogen on medullary bone and cortical bone in two species of Passeriformes: the Pine Siskin (Spinus pinus) and the House Finch (Haemorhous mexicanus). Females of these species received either an estradiol implant or were untreated as a control. After 4.5-5months, reproductive condition was assessed and leg (femora) and wing (humeri) bones were collected for analysis using high-resolution (10µm) micro-computed tomography scanning. We found that in both species estradiol-treated females had significantly greater medullary bone quantity in comparison to untreated females, but we found no differences in cortical bone quantity or microarchitecture. We were also able to examine medullary bone density in the pine siskins and found that estradiol treatment significantly increased medullary bone density. Furthermore, beyond the effect of the estradiol treatment, we observed a relationship between medullary bone quantity and ovarian condition that suggests that the timing of medullary bone formation may be related to the onset of yolk deposition in these species. Further research is needed to better understand the precise timing and endocrine regulation of medullary bone formation in Passerines and to determine the extent to which female Passerines rely on medullary bone calcium during the formation of calcified eggshells.

How Valid Is the Checklist for Autism Spectrum Disorder When a Child Has Apraxia of Speech?

OBJECTIVE: Our objective was to determine if the Checklist for Autism Spectrum Disorder (CASD) was inadvertently overemphasizing autism symptoms in a population of children without autism. METHODS: Children noted with communication delays were referred to both a developmental pediatrician and a speech and language pathologist for an apraxia and autism evaluation. All children who underwent both autism and apraxia evaluations and met rule-in or rule-out criteria for both diagnoses were included in the study, resulting in a sample size of 30. RESULTS: Our results show that 63.6% of children initially diagnosed with autism also had apraxia, 36.8% of children initially diagnosed with apraxia also had autism, 23.3% had neither, and 23.3% had both. Overall diagnostic accuracy for the CASD was 96.7%. Overall accuracy for the CASD for children without apraxia was 100% and accuracy for children with apraxia was 94.7%. Specificity for the CASD was 100%, while sensitivity was 90.9%. The PPV was 100% and the NPV was 95.0%. CONCLUSION: This study demonstrates that the CASD does not overemphasize autism symptoms in a population of children without autism. It also shows that autism and apraxia are highly comorbid. Thus, it is important to monitor all children diagnosed with apraxia for signs of autism and all children diagnosed with autism for signs of apraxia. This will help identify children as early as possible and allow them access to services appropriate to their needs.