Individuals’ Decision to Co-Donate or Donate Alone: An Archival Study of Married Whole Body Donors in Hawaii

Human cadavers are crucial to numerous aspects of health care, including initial and continuing training of medical doctors and advancement of medical research. Concerns have periodically been raised about the limited number of whole body donations. Little is known, however, about a unique form of donation, namely co-donations or instances when married individuals decide to register at the same time as their spouse as whole body donors. Our study aims to determine the extent of whole body co-donation and individual factors that might influence co-donation. Methods and Findings: We reviewed all records of registrants to the University of Hawaii Medical School's whole body donation program from 1967 through 2006 to identify married registrants. We then examined the 806 married individuals' characteristics to understand their decision to register alone or with their spouse. We found that married individuals who registered at the same time as their spouse accounted for 38.2 percent of married registrants. Sex differences provided an initial lens to understand co-donation. Wives were more likely to co-donate than to register alone (p = 0.002). Moreover, registrants' main occupational background had a significant effect on co-donations (p = 0.001). Married registrants (regardless of sex) in female-gendered occupations were more likely to co-donate than to donate alone (p = 0.014). Female-gendered occupations were defined as ones in which women represented more than 55 percent of the workforce (e.g., preschool teachers). Thus, variations in donors' occupational backgrounds explained co-donation above and beyond sex differences. Conclusions: Efforts to secure whole body donations have historically focused on individual donations regardless of donors' marital status. More attention needs to be paid, however, to co-donations since they represent a non-trivial number of total donations. Also, targeted outreach efforts to male and female members of female-gendered occupations might prove a successful way to increase donations through co-donations

Computerised 3-D anatomical modelling using plastinates: an example utilising the human heart

Computerised modelling methods have become highly useful for generating electronic representations of anatomical structures. These methods rely on crosssectional tissue slices in databases such as the Visible Human Male and Female, the Visible Korean Human, and the Visible Chinese Human. However, these databases are time consuming to generate and require labour-intensive manual digitisation while the number of specimens is very limited. Plastinated anatomical material could provide a possible alternative to data collection, requiring less time to prepare and enabling the use of virtually any anatomical or pathological structure routinely obtained in a gross anatomy laboratory. The purpose of this study was to establish an approach utilising plastinated anatomical material, specifically human hearts, for the purpose computerised 3-D modelling. Human hearts were collected following gross anatomical dissection and subjected to routine plastination procedures including dehydration (–25oC), defatting, forced impregnation, and curing at room temperature. A graphics pipeline was established comprising data collection with a hand-held scanner, 3-D modelling, model polishing, file conversion, and final rendering. Representative models were viewed and qualitatively assessed for accuracy and detail. The results showed that the heart model provided detailed surface information necessary for gross anatomical instructional purposes. Rendering tools facilitated optional model manipulation for further structural clarification if selected by the user. The use of plastinated material for generating 3-D computerised models has distinct advantages compared to cross-sectional tissue images. (Folia Morphol 2011; 70, 3: 191–196

A Unique Student Cohort’s Perceptions and Preferences about Gross Anatomy Education in the Medical Curriculum: JABSOM Student Survey 2020

Introduction: The SARS-CoV-2 (COVID) pandemic made it necessary for medical schools to integrate online learning into the delivery of curriculum involving cadaveric-based gross anatomy instruction and dissection, which may benefit post-COVID instruction. Objectives: The purpose of this study was to assess the perceptions of a unique student cohort arising from the COVID pandemic with respect to gross anatomy instruction. The hypothesis tested was that the medical student class of 2023’s perceptions concerning the delivery of gross anatomy education, as well as its educational significance, would differ between students that elected to dissect (D) compared with those who did not (N). Methods: A survey was conducted at the conclusion of the 2020 medical gross anatomy course at JABSOM, and 79 medical students responded to questions about the usefulness of anatomy, preference of lectures (slide decks without lectures, in-person lectures, live online lectures, and pre-recorded lectures) and dissection laboratories (no lab, live online labs, class in-person labs, and hybrid labs). The preference levels were assessed by Likert scale (highest, high, low, lowest), from which binary scale results (high or low) were also analyzed. Fisher’s exact tests were used to examine differences in survey responses between D (n=40) and N students (n=39). Open-ended questions were used to probe these perceptions. Results: D students rated gross anatomy’s usefulness more positively than N students (overall 87%; D 100%, N 74%, p<.001). More N students considered that anatomy dissection should be elective (overall 68%; D 38%, N 100%, p<.001). Overall, the students’ preference levels were high for live online lectures and pre-recorded lectures, and low for slide decks without lectures and in-person lectures. Pre-recorded lecture was rated the most valued, notably by D students (overall 80%; D 90%, N 68%, p=0.03), while slide decks without lecture was rated the lowest lecture-based modality (overall 80%; D 90%, N 68%, p=0.03). More than 90% of responses to open questions about the usefulness of pre-recorded lectures were positive. Hybrid lab was the most preferred laboratory type (high preference levels: overall 82%; D 72%, N 79%, p=0.02). No lab was least preferred and more disfavored by D students (overall 79%; D 90%, N 67%, p=0.01). Through open questions, most D students responded positively (95%) and had no regrets dissecting (86%). Discussion: Most students found dissection to be a useful educational activity. The benefits for students who elected to dissect included more opportunities to ask questions to instructors, better visibility of structures, and flexibility with dissection time. Students who did not elect to dissect felt safe during a pandemic, spent more time with loved ones, and had less financial burden commuting to school. The results show a strong contrast in that in-person lectures and slide decks without lectures were not preferred compared to live online lectures and pre-recorded lectures. Students expressed that watching lectures at their convenience benefited anatomy comprehension since more time was available to prepare rather than pursuing dissection immediately after a lecture traditionally. Among the methods for laboratory instruction experienced, the only significant preference was that no lab was the least preferred by the overall class. Although D was more extreme in opinion, N showed a similar trend with a large majority opting against no lab. A small minority of N did express regret not being to dissect during the unit, whether for academic or camaraderie-building benefit. Future work will be directed at assessing student perceptions concerning use of online technology as supplemental instruction for gross anatomy

Cut Out the Scalpel : Anxiety Reduction Before the First Dissection Experience Using Multimodal Media

Objective Using a multimedia-integrated exercise on cadavers to reduce anxieties of first-year medical students prior to their first dissection. Rationale: Dissection causes anxiety among matriculating medical students. With technological advancements, students can interact with cadavers beyond dissection. Prior computed tomography (CT) scan integration of cadavers was suboptimal, but full-body magnetic resonance imaging (MRIs) of cadavers as a learning tool has not been well studied and was explored in this study. Prior studies also explored anxiety at the first dissection. However, no study assessed anxiety and satisfaction pre/post-projection exercise guided by multimodal resources - before dissecting cadavers. Methods: During the first gross anatomy laboratory, students accessed the Anatomy XRCore website directing them to Sketchfab 3D models, donor MRIs, and projection instructions. A post-exercise survey was included and differences in responses between students without prior dissection experience (ND group) and with experience (ED group) were compared by Fisher’s exact test or Chi-squared test for categorical variables, and Wilcoxon rank sum test for continuous variables. Pre/post-exercise anxiety levels on a scale of 1-10 (10 = highest anxiety level) reported by a subsample group were compared by paired t-test. Results: Among 63 responses (mean age: 25.3 ± 3.3; female 58.7%), 98% completed the exercise. ND represented 63.5% (n=40) and ED represented 36.5% (n=23). Most students reported that the surface projection exercise was helpful for initiating teamwork (93.8%) and reducing anxiety (77.4%). 57.5% of ND reported decreased post-exercise anxiety compared to 26.1% of ED (p=0.044). Regarding the subsample (n=44), the mean anxiety level of ND decreased from 4.2 ± 2.9 to 3.2 ± 2.2 (p < 0.001) while no difference was found among ED. On a five-question Likert subscale (5 = strongly agreed) the benefit of this exercise before dissection received a mean score of 4.3 from all students. 95% agreed that MRIs improved their understanding of spatial relations. Potential Impact or Lessons Learned: Incorporating multimodal resources into an exercise that familiarizes students with human cadavers is perceived as favorable and decreases anxiety

Assessment of bone channels other than the nasopalatine canal in the anterior maxilla using limited cone beam computed tomography

Purpose: The anterior maxilla, sometimes also called premaxilla, is an area frequently requiring surgical interventions. The objective of this observational study was to identify and assess accessory bone channels other than the nasopalatine canal in the anterior maxilla using limited cone beam computed tomography (CBCT). Methods: A total of 176 cases fulfilled the inclusion criteria comprising region of interest, quality of CBCT image, and absence of pathologic lesions or retained teeth. Any bone canal with a minimum diameter of 1.00mm other than the nasopalatine canal was analyzed regarding size, location, and course, as well as patient gender and age. Results: A total of 67 accessory canals ≥1.00mm were found in 49 patients (27.8%). A higher frequency of accessory canals was observed in males (33.0%) than in females (22.7%) (p=0.130). Accessory canals occurred more frequently in older rather than younger patients (p=0.115). The mean diameter of accessory canals was 1.31±0.26mm (range 1.01-2.13mm). Gender and age did not significantly influence the diameter. Accessory canals were found palatal to all anterior teeth, but most frequently palatal to the central incisors. In 56.7%, the accessory canals curved superolaterally and communicated with the ipsilateral alveolar extension of the canalis sinuosus. Conclusions: The study confirms the presence of bone channels within the anterior maxilla other than the nasopalatine canal. More than half of these accessory bone canals communicated with the canalis sinuosus. From a clinical perspective, studies are needed to determine the content of these accessory canal

Canalization and developmental stability in the Brachyrrhine mouse

The semi-dominant Br mutation affects presphenoid growth, producing the facial retrognathism and globular neurocranial vault that characterize heterozygotes. We analysed the impact of this mutation on skull shape, comparing heterozygotes to wildtype mice, to determine if the effects are skull-wide or confined to the sphenoid region targeted by the mutation. In addition, we examined patterns of variability of shape for the skull as a whole and for three regions (basicranium, face and neurocranium). We found that the Br mice differed significantly from wildtype mice in skull shape in all three regions as well as in the shape of the skull as a whole. However, the significant increases in variance and fluctuating asymmetry were found only in the basicranium of mutant mice. These results suggest that the mutation has a significant effect on the underlying developmental architecture of the skull, which produces an increase in phenotypic variability that is localized to the anatomical region in which the mean phenotype is most dramatically affected. These results suggest that the same developmental mechanisms that produce the change in phenotypic mean also produce the change in variance.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75710/1/j.1469-7580.2006.00527.x.pd

Three‐dimensional myocardial scarring along myofibers after coronary ischemia–reperfusion revealed by computerized images of histological assays

Abstract Adverse left ventricular (LV) remodeling after acute myocardial infarction is characterized by LV dilatation and development of a fibrotic scar, and is a critical factor for the prognosis of subsequent development of heart failure. Although myofiber organization is recognized as being important for preserving physiological cardiac function and structure, the anatomical features of injured myofibers during LV remodeling have not been fully defined. In a mouse model of ischemia–reperfusion (I/R) injury induced by left anterior descending coronary artery ligation, our previous histological assays demonstrated that broad fibrotic scarring extended from the initial infarct zone to the remote zone, and was clearly demarcated along midcircumferential myofibers. Additionally, no fibrosis was observed in longitudinal myofibers in the subendocardium and subepicardium. However, a histological analysis of tissue sections does not adequately indicate myofiber injury distribution throughout the entire heart. To address this, we investigated patterns of scar formation along myofibers using three‐dimensional (3D) images obtained from multiple tissue sections from mouse hearts subjected to I/R injury. The fibrotic scar area observed in the 3D images was consistent with the distribution of the midcircumferential myofibers. At the apex, the scar formation tracked along the myofibers in an incomplete C‐shaped ring that converged to a triangular shape toward the end. Our findings suggest that myocyte injury after transient coronary ligation extends along myofibers, rather than following the path of coronary arteries penetrating the myocardium. The injury pattern observed along myofibers after I/R injury could be used to predict prognoses for patients with myocardial infarction

Transcriptional regulatory control of mammalian nephron progenitors revealed by multi-factor cistromic analysis and genetic studies

Nephron progenitor number determines nephron endowment; a reduced nephron count is linked to the onset of kidney disease. Several transcriptional regulators including Six2, Wt1, Osr1, Sall1, Eya1, Pax2, and Hox11 paralogues are required for specification and/or maintenance of nephron progenitors. However, little is known about the regulatory intersection of these players. Here, we have mapped nephron progenitor-specific transcriptional networks of Six2, Hoxd11, Osr1, and Wt1. We identified 373 multi-factor associated ‘regulatory hotspots’ around genes closely associated with progenitor programs. To examine their functional significance, we deleted ‘hotspot’ enhancer elements for Six2 and Wnt4. Removal of the distal enhancer for Six2 leads to a ~40% reduction in Six2 expression. When combined with a Six2 null allele, progeny display a premature depletion of nephron progenitors. Loss of the Wnt4 enhancer led to a significant reduction of Wnt4 expression in renal vesicles and a mildly hypoplastic kidney, a phenotype also enhanced in combination with a Wnt4 null mutation. To explore the regulatory landscape that supports proper target gene expression, we performed CTCF ChIP-seq to identify insulator-boundary regions. One such putative boundary lies between the Six2 and Six3 loci. Evidence for the functional significance of this boundary was obtained by deep sequencing of the radiation-induced Brachyrrhine (Br) mutant allele. We identified an inversion of the Six2/Six3 locus around the CTCF-bound boundary, removing Six2 from its distal enhancer regulation, but placed next to Six3 enhancer elements which support ectopic Six2 expression in the lens where Six3 is normally expressed. Six3 is now predicted to fall under control of the Six2 distal enhancer. Consistent with this view, we observed ectopic Six3 in nephron progenitors. 4C-seq supports the model for Six2 distal enhancer interactions in wild-type and Br/+ mouse kidneys. Together, these data expand our view of the regulatory genome and regulatory landscape underpinning mammalian nephrogenesis

Morphometry of the Cranial Base in Subjects with Class III Malocclusion

The significance of the cranial base in the development of Class III malocclusion remains uncertain. The purpose of this study was to determine whether the form of the cranial base differs between prepubertal Class I and Class III subjects. Lateral cephalographs of 73 children of European-American descent aged between 5 and 11 years with Class III malocclusion were compared with those of their counterparts with a normal, Class I molar occlusion. The cephalographs were traced, checked, and subdivided into seven age- and sex-matched groups. Average geometries, scaled to an equivalent size, were generated based on 13 craniofacial landmarks by means of Procrustes analysis, and these configurations were statistically tested for equivalence. Bivariate and multivariate analyses utilizing 5 linear and angular measurements were undertaken to corroborate the Procrustes analysis. Graphical analysis, utilizing thin-plate spline and finite element methods, was performed for localization of differences in cranial base morphology. Results indicated that cranial base morphology differed statistically for all age-wise comparisons. Graphical analysis revealed that the greatest differences in morphology occurred in the posterior cranial base region, which generally consisted of horizontal compression, vertical expansion, and size contraction. The sphenoidal region displayed expansion, while the anterior regions showed shearing and local increases in size. It is concluded that the shape of the cranial base differs in subjects with Class III malocclusion compared with the normal Class I configuration, due in part to deficient orthocephalization, or failure of the cranial base to flatten during development.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67377/2/10.1177_00220345970760021101.pd

Transcriptional regulatory control of mammalian nephron progenitors revealed by multi-factor cistromic analysis and genetic studies.

Nephron progenitor number determines nephron endowment; a reduced nephron count is linked to the onset of kidney disease. Several transcriptional regulators including Six2, Wt1, Osr1, Sall1, Eya1, Pax2, and Hox11 paralogues are required for specification and/or maintenance of nephron progenitors. However, little is known about the regulatory intersection of these players. Here, we have mapped nephron progenitor-specific transcriptional networks of Six2, Hoxd11, Osr1, and Wt1. We identified 373 multi-factor associated \u27regulatory hotspots\u27 around genes closely associated with progenitor programs. To examine their functional significance, we deleted \u27hotspot\u27 enhancer elements for Six2 and Wnt4. Removal of the distal enhancer for Six2 leads to a ~40% reduction in Six2 expression. When combined with a Six2 null allele, progeny display a premature depletion of nephron progenitors. Loss of the Wnt4 enhancer led to a significant reduction of Wnt4 expression in renal vesicles and a mildly hypoplastic kidney, a phenotype also enhanced in combination with a Wnt4 null mutation. To explore the regulatory landscape that supports proper target gene expression, we performed CTCF ChIP-seq to identify insulator-boundary regions. One such putative boundary lies between the Six2 and Six3 loci. Evidence for the functional significance of this boundary was obtained by deep sequencing of the radiation-induced Brachyrrhine (Br) mutant allele. We identified an inversion of the Six2/Six3 locus around the CTCF-bound boundary, removing Six2 from its distal enhancer regulation, but placed next to Six3 enhancer elements which support ectopic Six2 expression in the lens where Six3 is normally expressed. Six3 is now predicted to fall under control of the Six2 distal enhancer. Consistent with this view, we observed ectopic Six3 in nephron progenitors. 4C-seq supports the model for Six2 distal enhancer interactions in wild-type and Br/+ mouse kidneys. Together, these data expand our view of the regulatory genome and regulatory landscape underpinning mammalian nephrogenesis