Noggin signaling from Xenopus animal blastomere lineages promotes a neural fate in neighboring vegetal blastomere lineages.

In Xenopus, localized factors begin to regionalize embryonic fates prior to the inductive interactions that occur during gastrulation. We previously reported that an animal-to-vegetal signal that occurs prior to gastrulation promotes primary spinal neuron fate in vegetal equatorial (C-tier) blastomere lineages. Herein we demonstrate that maternal mRNA encoding noggin is enriched in animal tiers and at low concentrations in the C-tier, suggesting that the neural fates of C-tier blastomeres may be responsive to early signaling from their neighboring cells. In support of this hypothesis, experimental alteration of the levels of Noggin from animal equatorial (B-tier) or BMP4 from vegetal (D-tier) blastomeres significantly affects the numbers of primary spinal neurons derived from their neighboring C-tier blastomeres. These effects are duplicated in blastomere explants isolated at cleavage stages and cultured in the absence of gastrulation interactions. Co-culture with animal blastomeres enhanced the expression of zygotic neural markers in C-tier blastomere explants, whereas co-culture with vegetal blastomeres repressed them. The expression of these markers in C-tier explants was promoted when Noggin was transiently added to the culture during cleavage/morula stages, and repressed with the transient addition of BMP4. Reduction of Noggin translation in B-tier blastomeres by antisense morpholino oligonucleotides significantly reduced the efficacy of neural marker induction in C-tier explants. These experiments indicate that early anti-BMP signaling from the animal hemisphere recruits vegetal equatorial cells into the neural precursor pool prior to interactions that occur during gastrulation.     

Local properties of a functionally graded interphase between cementum and dentin

The study of natural interfaces may provide information necessary to engineer functionally graded biomaterials for bioengineering applications. In this study, the mechanical, structural, and chemical composition variations associated with a region between cementum and dentin were studied with the use of nanoindentation, microindentation, optical microscopy, and Raman microspectroscopy techniques. Three-millimeter-thick transverse sections (N = 5) were obtained from the apical one-third of the roots of sterilized human molars. The samples were ultrasectioned at room temperature with the use of a diamond knife and an ultramicrotome. Longitudinal ground sections of 100 microm thickness were prepared and stained with von Kossa stain to determine the mineralized regions within the molar roots. Raman microspectroscopy was used to determine the relative inorganic content, mainly apatite (PO4(3-)nu1 mode at 960 cm(-1)) and organic content, mainly collagen (C--H stretch at 2940 cm(-1)) between cementum and dentin bulk tissues. The microindentation and nanoindentation results indicated a gradual transition in hardness from cementum to dentin over a width ranging from 100 to 200 microm. However, the variation in hardness data for cementum and dentin by nanoindentation was larger (0.62 +/- 0.21, 0.77 +/- 0.14 GPa) than from microindentation (0.49 +/- 0.03, 0.69 +/- 0.07 GPa). Within the 100 to 200 microm region there was a 10 to 50 microm fibrillar hydrophilic cementum-dentin junction (CDJ) with mechanical properties significantly lower than either the cementum or the dentin side of CDJ. Light microscopy revealed a 100 to 200 microm translucent region between cementum and dentin. Raman microspectroscopy results showed a variation in organic and inorganic composition 80 to 140 microm wide. It was concluded that a morphologically and biomechanically different CDJ lies within a wider cementum-dentin interphase. Hence, cementum, dentin, and the interphase can be classified as a functionally graded dental tissue within the root of a tooth.     

Associations of place of birth with asthma and wheezing in Mexican American children

BACKGROUND: There are wide global variations in the prevalence of asthma and wheezing. OBJECTIVES: We examined the associations of place of birth with doctor-diagnosed asthma, wheezing in the past 12 months, and other allergic conditions in Mexican American children. METHODS: The study used data on 4121 Mexican American children age 2 months to 16 years who participated in the Third National Health and Nutrition Examination Survey. RESULTS: The risk of asthma was associated with being born in the United States after adjusting for sex, age, history of ear infection, and having a regular place for health care (odds ratio, 2.19; 95% CI, 1.09-4.40). Among children with no previous history of ear infection, US-born children were more likely to report wheezing in the past 12 months than their peers born in Mexico after controlling for confounding variables (odds ratio, 2.05; 95% CI, 1.09-3.87). Mexican American children born in the United States were more likely to have positive skin reaction to cat, house mite, Alternaria alternata , peanut, Bermuda grass, and short ragweed but were less likely to have a positive skin test to German cockroaches after adjusting for sex, age, ear infection, having a regular place for health care, and area of residence. CONCLUSION: Our study indicated significant associations of place of birth with respiratory symptoms and allergic conditions in Mexican American children. These findings highlight the need for further studies to examine environmental factors that change by migration and explain the observed differential in the risk of asthma or wheezing.     

Short-termin vivo stability of endothelial-lined polyester elastomer and polytetrafluoroethylene grafts

A fibronectin substrate will significantly enhance the strength of endothelial cell attachment on grafts constructed of polyester elastomer (PE) and polytetrafluoroethylene (e-PTFE). This experiment was undertaken to determine the short-termin vivo stability of endothellum on these fibronectin coated surfaces. Eight mongrel dogs underwent bilateral carotid artery replacement with both graft materlals. All grafts were inoculated with 2,000 cells/mm² using cultured autogenous venous endothelium labelled with Indium-111-oxine. The Indium-111 label in the grafts was measured immediately prior to implantation, after 1 hour ofin vivo perfusion, and at explantation after 24 hours. The percentage of inoculated cells attached to the grafts before perfusion was simillar for both materials, 93.3±3.0% versus 92.2±7.2%, for PE and e-PTFE respectively. All grafts were patent at one hour after implantation. PE grafts were found to have 93.8±3.9 % of the attached cells present at one hour while e-PTFE grafts had only 54.5 ± 10.8 % remaining, p<.001. After 24 hours, 5/8 (62.5%) e-PTFE grafts and 2/8 (25.0 %) PE grafts remained patent, p=.13. Of the patent grafts however, endothelial cell retention was still superior on the PE grafts with 78.0±0.6% of the attached cells remaining compared to only 24.5±6.1% on e-PTFE, p<.001. Occluded PE grafts had fewer cells remaining at 24 hours than patent ones, 78.0±0.6% versus 31.1±32.8%, respectively, p=.13. Histologically, patent PE grafts demonstrated nearly confluent endothelial monolayers while e-PTFE had patches of endothelial cells surrounded by, a platelet-fibrin carpet. We conclude that short-term patency appears to be determined by the extent of endothelial retention on PE but not e-PTFE.     

The Joint Effects of Diet and Dietary Supplements in Relation to Obesity and Cardiovascular Disease over a 10-Year Follow-Up: A Longitudinal Study of 69,990 Participants in Australia

It is unknown whether a healthy diet or unhealthy diet combined with specific supplements may jointly contribute to incidence of obesity and cardiovascular disease (CVD). We included 69,990 participants from the 45 and Up Study who completed both baseline (2006–2009) and follow-up (2012–2015) surveys. We found that compared to participants with a long-term healthy diet and no supplement consumption, those with a long-term healthy diet combined with multivitamins and minerals (MVM) or fish oil consumption were associated with a lower incidence of CVD (p < 0.001); whilst those with an unhealthy diet and no MVM or fish oil consumption were associated with a higher risk of obesity (p < 0.05). Compared to participants with a long-term healthy diet and no calcium consumption, the combination of a long-term healthy diet and calcium consumption was linked to a lower risk of CVD (IRR = 0.87, 95% CI: 0.78; 0.96). In conclusion, a long-term healthy diet combined with MVM or fish oil was associated with a lower incidence of CVD. Participants who maintained a healthy diet and used calcium supplements were associated with a lower incidence of obesity. However, these associations were not found among those with an unhealthy diet, despite taking similar supplements.     

A Cross-Country Network Analysis of Adolescent Resilience

PurposeIn situations of adversity, young people draw on individual, relational, and contextual (community and cultural) resources to foster their resilience. Recent literature defines resilience as a capacity that is underpinned by a network of interrelated resources. Although empirical studies show evidence of the value of a network approach, little is known regarding how different country contexts influence which resources are most critical within a resource network and how resources interact for adolescent resilience.MethodsNetwork analysis was conducted with data from studies that had used the Child and Youth Resilience Measure. Regularized partial correlation networks of 17 resources were estimated for 14 countries (Botswana, Canada, China, Colombia, Equatorial Guinea, India, Indonesia, Italy, Jordan, New Zealand, the Philippines, Romania, South Africa, and Syrian refugees living in Jordan). The sample size was 18,914 (mean age = 15.70 years, 48.8% female).ResultsWe observed mostly positive associations between the resources of interest. The salience and strength of associations between resources varied by country. The most central resource across countries was having supportive caregivers during stressful times because this resource had the most and strongest positive associations with other resources.ConclusionsThis study gives first empirical evidence from multiple countries that an interplay of social–ecological resources (such as individual skills, peer, caregiver and community support, and educational aspirations and opportunities) matter for adolescent resilience. Across countries, caregiver support appears to be most central for adolescent resilience. Future resilience interventions might apply this network approach to identify important, contextually relevant resources that likely foster additional resources.     

Heterotopic Ossification Negatively Influences Range of Motion After Revision Total Knee Arthroplasty

BackgroundThe incidence of heterotopic ossification (HO) after total knee arthroplasty (TKA) varies and is of unclear clinical significance. This study aimed to identify the incidence of HO in patients undergoing revision TKA for either stiffness or aseptic loosening/instability and determine if the presence of HO is associated with inferior absolute range of motion (ROM) and ROM gains.MethodsEighty-seven patients were prospectively enrolled and separated into 2 cohorts to evaluate ROM after revision TKA (2017-2019). Group 1 (N = 40) patients were revised for stiffness, while group 2 (N = 47) patients were revised for either aseptic loosening or instability. Goniometer-measured ROM values were obtained preoperatively and at 6 weeks, 6 months, and 1 year postoperatively. Statistical analysis included a Fisher’s exact test to assess for an association between preoperative HO and final ROM at 1 year after revision TKA.ResultsHO was identified on preoperative radiographs in 17 patients (20%). There was a significantly higher rate of preoperative HO in patients revised for stiffness compared to patients revised for instability or loosening (30% vs 11%; P = .03). Five cases of HO qualitatively identified as most clinically severe were associated with lower ROM at each time point compared to the remainder of HO cases in this study cohort (P < .02).ConclusionThe presence of HO is greater in patients undergoing revision TKA for stiffness. Additionally, HO severity appears to have a major effect on preoperative and postoperative ROM trajectory. This information should help guide patient expectations and highlight the need for a comprehensive, standardized classification system for HO.     

A specific enhanced recovery protocol decreases opioid use after thyroid and parathyroid surgery

BackgroundEnhanced recovery protocols have not been investigated previously for cervical endocrine surgery. The study aim was to determine whether systematic implementation of an enhanced recovery protocol specific for thyroid/parathyroid surgery can improve postoperative outcomes.MethodsA customized enhanced recovery protocol for thyroid/parathyroid surgery was designed and utilized systematically for all patients who underwent parathyroidectomy, thyroid lobectomy, or total thyroidectomy. Outcomes were assessed 12 months before enhanced recovery protocol implementation (n = 464 patients) and after enhanced recovery protocol implementation (n = 654 patients).ResultsEnhanced recovery protocol implementation was associated with a 72% decrease in mean oral morphine equivalents utilized in-house (before 82 ± 64 versus after 23 ± 28; P < .0001) and many enhanced recovery protocol patients were entirely opioid-free (0.2% vs 21%, P < .0001). When used, the enhanced recovery protocol was associated with a lesser mean amount of ondansetron to treat postoperative nausea and vomiting (5.5 mg ± 3 vs 4.5 ± 2: P < .0001). Duration of stay was short before implementation of the enhanced recovery protocol and did not change substantially after implementation (1.1 days ± 0.7 vs 1.1 ± 0.7; P = .26).ConclusionThe systematic use of a simple, cervical, endocrine surgery-specific enhanced recovery protocol decreased perioperative opioid use by ~70%, with significantly less postoperative nausea and vomiting. Implementation of a multidisciplinary enhanced recovery protocol may be an important initial step toward limiting opioid overuse during common operative procedures.