Peter Kondrashov

Impact of the clinical ultrasound elective course on retention of anatomical knowledge by second-year medical students in preparation for board exams.

Ultrasound has been integrated into a gross anatomy course taught during the first year at an osteopathic medical school. A clinical ultrasound elective course was developed to continue ultrasound training during the second year of medical school. The purpose of this study was to evaluate the impact of this elective course on the understanding of normal anatomy by second‐year students. An anatomy exam was administered to students enrolled in the clinical ultrasound elective course before the start of the course and after its conclusion. Wilcoxon signed ranks tests were used to determine whether exam scores changed from the pre‐test to the post‐test. Scores from two classes of second‐year students were analyzed. Students who took the elective course showed significant improvement in the overall anatomy exam score between the pre‐test and post‐test (P < 0.001). Scores for exam questions pertaining to the heart, abdomen, upper extremity, and lower extremity also significantly improved from the pretest to post‐test (P < 0.001), but scores for the neck and eye showed no significant improvement. The clinical ultrasound elective course offered during the second year of medical school provided students with an important review of key anatomical concepts while preparing them for board exams. Our results suggested that more emphasis should be placed on head and neck ultrasound to improve student performance in those areas. Musculoskeletal, abdominal, and heart ultrasound labs were more successful for retaining relevant anatomical information. Clin. Anat. 28:156–163, 2015.

Circumventing the polydactyly ‘constraint’: the mole's ‘thumb’

Talpid moles across all northern continents exhibit a remarkably large, sickle-like radial sesamoid bone anterior to their five digits, always coupled with a smaller tibial sesamoid bone. A possible developmental mechanism behind this phenomenon was revealed using molecular markers during limb development in the Iberian mole (Talpa occidentalis) and a shrew (Cryptotis parva), as shrews represent the closest relatives of moles but do not show these conspicuous elements. The moles radial sesamoid develops later than true digits, as shown by Sox9, and extends into the digit area, developing in relation to an Msx2-domain at the anterior border of the digital plate. Fgf8 expression, marking the apical ectodermal ridge, is comparable in both species. Developmental peculiarities facilitated the inclusion of the moles radial sesamoid into the digit series; talpid moles circumvent the almost universal pentadactyly constraint by recruiting wrist sesamoids into their digital region using a novel developmental pathway and timing.

New gastropod species from the Pleistocene of the Upper Don basin

Two new species of fossil freshwater gastropods, Borysthenia intermedia sp. nov. and Tanousia krasnenkovi sp. nov., from the Tiraspol deposits of the Middle Pleistocene of the Oka-Don Plain are described. Parafossarulus priscillae (Girotti, 1972), Viviparus diluvianus (Künth, 1865), and Lithoglyphus jahni Urbasnski, 1975 are reported from Russia for the first time. The status of some problematic species of freshwater gastropods from the Middle Pleistocene of the region studied is discussed. The chronological and environmental significance of all gastropods studied is given.

Nearly Complete Skeleton of Tetraclaenodon (Mammalia, Phenacodontidae) from the Early Paleocene of New Mexico: Morpho-Functional Analysis

Abstract We describe the relatively complete skeleton of Tetraclaenodon undoubtedly associated with its dentition, from the Torrejonian interval of the Nacimiento Formation in the San Juan Basin, New Mexico. Tetraclaenodon is the most primitive and oldest genus of the family Phenacodontidae and is very important for assessing the phylogenetic relationships of the family. The newly described skeleton belonged to a lightly built terrestrial mammal that could use trees for shelter. The structure of the ulna, manus, femur, crus, and pes corresponds to that of a typical terrestrial mammal, while morphological features such as the low greater tubercle of the humerus, long deltopectoral crest, pronounced lateral supracondylar crest, and hemispherical capitulum indicate some scansorial adaptations of Tetraclaenodon. The postcranial skeleton of Tetraclaenodon does not exhibit the cursorial adaptations seen in later phenacodontids and early perissodactyls. Phylogenetic analysis did not recover monophyletic “Phenacodontidae”; instead, phenacodontids formed a series of sister taxa to the Altungulata clade. Tetraclaenodon is the basal-most member of the “Phenacodontidae” + Altungulata clade.

A nearly complete skeleton of Ernanodon (Mammalia, Palaeanodonta) from Mongolia: morphofunctional analysis

ABSTRACT Ernanodon, one of the most enigmatic Asian fossil mammals, was previously known by a single specimen from the late Paleocene (Nongshanian) of China. Here we document the first record of Ernanodon from Mongolia, represented by a nearly complete skeleton from the late Paleocene (Gashatan) of the Naran Bulak locality. The new material provides an opportunity to understand the lifestyle and habits of this rare mammal and reevaluate the arguments used to establish the phylogenetic relationships of Ernanodon. Functional analysis indicates that Ernanodon had very strong forelimbs with large claws and used its forelimbs for scratch-digging. Character analysis reveals numerous similarities in postcranial anatomy between Ernanodon and Palaeanodonta. Phylogenetic analysis supports inclusion of Ernanodon in the order Palaeanodonta and suggests that Palaeanodonta and Pholidota are sister groups.

Mollusks and small mammals from the Kuznetsovka locality, Pleistocene of the Oka-Don Plain

Kuznetsovka, a very rich locality of Interglacial mollusks and small mammals overlies the Donian Glacial strata of the Oka-Don Plain. Mollusks and small mammal from this locality are described in detail. The crucial stage in the development of Middle Pleistocene mollusk and mammal faunas is investigated. The data obtained allow the dating of fossiliferous deposits and reconstruction of sedimentation and environmental conditions of the fauna. The comparison of the Kuznetsovka Fauna with materials from central and western Europe permits its direct correlation with the fauna of the Cromerian stratotype in West Runton (Norfolk, England). Thus, the deposits of the Kuznetsovka section were formed during the second half of the early Middle Pleistocene.

The role of excessive body weight and meniscal instability in the progression of osteoarthritis in a rat model

BACKGROUND The main objective of the study was to determine if excessive body weight and meniscal destabilization cause knee articular cartilage damage and changes in meniscal histology indicative of knee osteoarthritis (OA). METHODS Forty female Lewis rats were randomly assigned to regular diet sham surgery, regular diet medial meniscus destabilization (DMM) surgery, high-fat diet sham surgery, or high-fat diet DMM surgery. Surgical intervention occurred four weeks after diet initiation. Rats were sacrificed four weeks post-surgery. Progression of OA was evaluated in femoral condyles and tibial plateaus using the Osteoarthritis Research Society International (OARSI) scoring system by two blinded scorers. Ossification of menisci was evaluated with digitized histological slides using a grid. RESULTS DMM surgery had greater OARSI scores than sham surgery for all knee surfaces in both diet groups (all P < 0.004). The high-fat diet sham surgery group had greater OARSI scores than the regular diet sham surgery group on all knee surfaces (all P < 0.02). Histological evaluation showed the lateral meniscus had more bone than the medial meniscus, but there was no relationship between diet or surgery groups and amount of bone in the meniscus. CONCLUSIONS Results suggested excessive body weight may contribute to spontaneous onset of OA and emphasized the importance of preventative care in those at risk of developing OA.

Integration of ultrasound imaging into pre-clinical dental education

INTRODUCTION Patients have complex healthcare needs and typically require more than one healthcare discipline to address issues regarding their health. Interprofessional teams of healthcare professionals may be able to address these complex needs and improve patient outcomes by combining resources. To evaluate the feasibility of integrating ultrasound into a dental school curriculum to teach anatomy as part of an interprofessional education experience, the current study surveyed first-year dental students to determine their perceptions of the integration of ultrasound techniques into the curriculum. MATERIALS AND METHODS Ultrasound laboratory exercises were developed for first-year dental students as part of their anatomy course. The exercises were focused on head, neck and abdominal anatomy. To assess student perception of the integration of ultrasound into the dental curriculum, a survey was created specifically for the current study. RESULTS Between 2013 and 2015, two classes of first-year dental students participated in the ultrasound laboratory exercise and completed the survey (n = 83). Student survey responses suggested ultrasound was a valuable teaching tool because it allowed them to visualise anatomical structures using live imaging. They also agreed that the ultrasound laboratory exercises were an efficient learning tool, but the majority did not believe that they would use ultrasound regularly in their future practice. CONCLUSIONS Results of the current study suggested first-year dental students were satisfied with the integration of ultrasound techniques into the dental curriculum. Survey results indicated that the students enjoyed the ultrasound laboratory exercise and felt ultrasound was an effective learning tool.

Premedical anatomy experience and student performance in medical gross anatomy: Impact of Pre-Medical Anatomy Experience

Gross anatomy is considered one of the most important basic science courses in medical education, yet few medical schools require its completion prior to matriculation. The effect of taking anatomy courses before entering medical school on performance in medical gross anatomy has been previously studied with inconsistent results. The effect of premedical anatomy coursework on performance in medical gross anatomy, overall medical school grade point average (GPA), and Comprehensive Osteopathic Medical Licensing Examination Level 1 (COMLEX 1) score was evaluated in 456 first‐year osteopathic medical students along with a survey on its perceived benefits on success in medical gross anatomy course. No significant differences were found in gross anatomy grade, GPA, or COMLEX 1 score between students with premedical anatomy coursework and those without. However, significant differences and higher scores were observed in students who had taken three or more undergraduate anatomy courses including at least one with cadaveric laboratory. There was significantly lower perceived benefit for academic success in the medical gross anatomy course (P<.001) from those students who had taken premedical anatomy courses (5.9 of 10) compared with those who had not (8.2 of 10). Results suggest that requiring any anatomy course as a prerequisite for medical school would not have significant effect on student performance in the medical gross anatomy course. However, requiring more specific anatomy coursework including taking three or more undergraduate anatomy courses, one with cadaveric laboratory component, may result in higher medical gross anatomy grades, medical school GPA, and COMLEX 1 scores. Clin. Anat. 30:303–311, 2017.

Histological Characteristics of Knee Menisci in Patients with Osteoarthritis

Existing data indicate knee menisci in patients with osteoarthritis (OA) show tearing, maceration, and fragmentation, but little is known about the change in histological structure. The aim of this study was to evaluate the change in the menisci histological structure in patients with clinically diagnosed knee OA. Fourteen patients undergoing surgical treatment of knee OA (OA group) and 14 cadaveric knees (control group) were assessed. Demographic data, medical history, synovial fluid, OA severity, medial meniscus (MM) tissue, and lateral meniscus (LM) tissue were collected from the OA group. Three nonconsecutive 10 μm cross‐sectional tissue slices of menisci were analyzed for percentage of tissue calcification. Exact Mann–Whitney tests and Spearman correlation coefficients tested for relationships between variables. The major change in the histological structure of the menisci in patients with OA was calcification of the matrix, which was significantly greater in the OA group compared with the control group for MM (OA: 11.9%, cadaver: 5.17%; P < 0.001) and LM tissues (OA: 11.1%, cadaver: 4.2%; P < 0.001). A correlation between percent calcification of the MM and LM tissues existed in the OA group (ρ = 0.56, P = 0.04) but not the control group (P = 0.20). The most pronounced pathological change in the histology of menisci was calcification of the cartilage matrix, significantly greater in the OA group than the control group. A strong correlation between percent calcification of MM and LM tissues in patients with OA indicates changes in fibrocartilage matrix of menisci progress similarly in the medial and lateral compartments of the knee. Clin. Anat. 30:805–810, 2017.