Rgs19 regulates mouse palatal fusion by modulating cell proliferation and apoptosis in the MEE.

Palatal development is one of the critical events in craniofacial morphogenesis. During fusion of the palatal shelves, removal of the midline epithelial seam (MES) is a fundamental process for achieving proper morphogenesis of the palate. The reported mechanisms for removing the MES are the processes of apoptosis, migration or general epithelial-to-mesenchymal transition (EMT) through modulations of various signaling molecules including Wnt signaling. RGS19, a regulator of the G protein signaling (RGS) family, interacts selectively with the specific α subunits of the G proteins (Gαi, Gαq) and enhances their GTPase activity. Rgs19 was reported to be a modulator of the Wnt signaling pathway. In mouse palatogenesis, the restricted epithelial expression pattern of Rgs19 was examined in the palatal shelves, where expression of Wnt11 was observed. Based on these specific expression patterns of Rgs19 in the palatal shelves, the present study examined the detailed developmental function of Rgs19 using AS-ODN treatments during in vitro palate organ cultivations as a loss-of-function study. After the knockdown of Rgs19, the morphological changes in the palatal shelves was examined carefully using a computer-aided three dimensional reconstruction method and the altered expression patterns of related signaling molecules were evaluated using genome wide screening methods. RT-qPCR and in situ hybridization methods were also used to confirm these array results. These morphological and molecular examinations suggested that Rgs19 plays important roles in palatal fusion through the degradation of MES via activation of the palatal fusion related and apoptotic related genes. Overall, inhibition of the proliferation related and Wnt responsive genes by Rgs19 are required for proper palatal fusion.

Effects of fraction obtained from Korean Corni Fructus extracts causing anti-proliferation and p53-dependent apoptosis in A549 lung cancer cells.

Corni Fructus has traditionally been used as herbal medicine for the treatment of tuberculosis, asthma, hepatitis, and chronic nephritis in Korea, Japan, and China. This research was carried out to evaluate the proliferative-inhibitory effect of CF extracts against cancer cells and to identify the new pro-substance from medicinal plants. Among these herbal extracts extracted from KCF (Korean Corni Fructus), JCF (Japanese Corni Fructus) and CCF (Chinese Corni Fructus), KCF extracts strongly induced anti-proliferation of cancer cells in a dose-dependent manner compared with other extracts. Moreover, after treatment with CM/F3 (fraction 3 obtained from KCF extracts) for 24 h, A549 cells were evaluated by several indicators such as cell viability, LDH release, DNA fragmentation, nuclear condensation, and apoptotic proteins in vitro. CM/F3 showed the tumor-selective growth inhibitory activity in a dose- and time-dependent manner in A549 cells. Consistently, CM/F3 effectively induced the activation of bax, cytochrome-c, caspase-3, -8, -9, p53, and p21 causing apoptosis, and caused the suppression of Cdk2, pRb, and E2F1 related to cell arrest in A549 cells. These results demonstrate that CM/F3 caused not only anti-proliferation but also cell death involving cell arrest through interaction between apoptotic proteins and the upregulation of p53 in A549 cells.

Extra- and intramuscular nerve distribution patterns of the muscles of the ventral compartment of the forearm.

OBJECTIVE: This study describes the extra- and intramuscular nerve branching of muscles of the ventral compartment of forearm, thereby providing critical information on determining the points for botulinum toxin injections that would be effective at reducing muscular spasticity. DESIGN: Twenty-three Korean and French cadavers were dissected and subjected to Modified Sihler's staining to investigate nerve entry points and intramuscular nerve arborization patterns. Nerve entry point and abundant arborizing area of each muscle were analyzed on 20 segments with reference to transverse lines obtained by dividing the forearm into ten equal divisions and a vertical line bisecting the medial and lateral halves of the forearm. RESULTS: The nerve entry points of the first and second layers of forearm muscles were located at medial levels 3 and 2, respectively. The entry points of the median and ulnar nerves innervating the flexor digitorum profundus (third layer) were located at medial levels 4 and 3, respectively. The intramuscular regions of abundant arborization in each muscle were located one level distal to the nerve entry point. CONCLUSIONS: This study has yielded a map of nerve entry and abundant arborization of motor nerves innervating each muscle of the ventral compartment of the forearm.

Location of the mandibular canal and the topography of its neurovascular structures.

The major complication in dental implant surgery is loss of sensation due to damage to the inferior alveolar nerve resulting from poor characterization of the location of the mandibular canal and the traveling course of the inferior alveolar nerve, artery, and vein therein. The purposes of this study were to determine the buccolingual location of the mandibular canal and to verify the topography of the inferior alveolar nerve, artery, and vein therein by three-dimensional reconstruction of these structures. Sixty-two mandible sides were used for this study. The buccolingual location of the mandibular canal was classified into 3 types: type 1 (70%), where the canal follows the lingual cortical plate at the mandibular ramus and body; type 2 (15%), where the canal follows the middle of the ramus behind the second molar and the lingual plate passing through the second and first molars; and type 3 (15%), where the canal follows the middle or the lingual one third of the mandible from the ramus to the body. Three-dimensional reconstruction of the mandibular canal revealed that the inferior alveolar vessel traveled above the inferior alveolar nerve in 8 cases (80%), with the inferior alveolar artery being lingual to the inferior alveolar vein, and in 2 cases (20%) where the inferior alveolar vessel was buccal to the nerve.

Topographic and histologic characteristics of the sural nerve for use in nerve grafting.

The sural nerve (SN) is a sensory nerve supplying the skin of the lateral and posterior parts of the inferior third of the calf and the lateral side of the foot and is easy to harvest because of its location posterior and superior to the tip of the lateral malleolus. Seventy-one lower limbs from 42 Korean cadavers were dissected to describe the joining type and level of perforated the fascia of the SN. The segments of sural nerve were stained and measured. The communication and joining patterns of the SN formed by the medial sural cutaneous nerve and the communicating branch of the lateral sural cutaneous nerve could be divided into five types. The region where the medial sural cutaneous nerve and the communicating branch of the lateral sural cutaneous nerve join together was observed in 52 cases with this found in the lower two fifths of the calf in 28 (53.8%) of the specimens. The mean number of fascicles was 8.1 (range, 2-12) at the lower calf and 5.8 (range, 1-11) at the middle calf before where the medial sural cutaneous nerve and the communicating branch of the lateral sural cutaneous nerve joined. The mean total areas of the fascicles were 0.55 mm and 0.43 mm in the lower and middle calf, respectively. This study demonstrates that the anatomy of the SN affects its harvesting for use in nerve grafts with the reported results providing a useful reference for SN grafting procedures.

An anatomic assessment on perforators of the lateral circumflex femoral artery for anterolateral thigh flap.

The anterolateral thigh flap was originally described in 1984 as a septocutaneous flap based on the descending branch of the lateral femoral circumflex artery (LCFA). This flap has many advantages for head and neck reconstruction. However, it is not widely used as a result of the broad range of anatomic variation of the cutaneous perforators and because dissection of these perforators is tedious when they are small. The purposes of this study are to classify the vascular anatomy of the LCFA and to assess the suitability of the anterolateral thigh flap for head and neck reconstruction in Koreans. From 38 thigh dissections of Korean cadavers, the LCFA commonly arose from the deep femoral artery and divided into ascending, transverse, and descending branches. In five cases, the LCFA arose directly from the femoral artery. The cutaneous perforators were present in 37 cases except one and the septocutaneous perforators were found in 17 of the 38 cases. Of the 160 perforators, 28 (17.5%) were the septocutaneous perforators and 132 (82.5%) were the musculocutaneous perforators. The average number of cutaneous perforators for the anterolateral thigh flap was 4.2 (range, 0-8), and these perforators were concentrated in the middle third of the anterolateral thigh. The septocutaneous perforators were located more proximally than the musculocutaneous perforators. The average length of the vascular pedicle derived from the descending branch or the transverse branch was 83.3 mm (range, 53.4-124.3 mm). The results of this study suggest that the vascular anatomy of the anterolateral thigh flap was reliable and well suited for head and neck reconstruction in Koreans.

Soft-tissue and cortical-bone thickness at orthodontic implant sites.

INTRODUCTION: To obtain sufficient stability of implants, the thickness of the soft tissue and the cortical bone in the placement site must be considered. However, the literature contains few anatomical studies of orthodontic implants. METHODS: To measure soft-tissue and cortical-bone thicknesses, maxillae from 23 Korean cadavers were decalcified, and buccopalatal cross-sectional specimens were obtained. These specimens were made at 3 maxillary midpalatal suture areas: the interdental area between the first and second premolars (group 1), the interdental area between the second premolar and the first molar (group 2), and the interdental area between the first and second molars (group 3). RESULTS: In all groups, buccal soft tissues were thickest closest to and farthest from the cementoenamel junction (CEJ) and thinnest in the middle. Palatal soft-tissue thickness increased gradually from the CEJ toward the apical region in all groups. Buccal cortical-bone was thickest closest to and farthest from the CEJ and thinnest in the middle in groups 1 and 2. Palatal cortical-bone thickness was greatest 6 mm apical to the CEJ in groups 1 and 3, and 2 mm apical to the CEJ in group 2. Along the midpalatal suture, palatal mucosa remained uniformly 1 mm thick posterior to the incisive papilla. CONCLUSIONS: Surgical placement of miniscrew implants for orthodontic anchorage in the maxillary molar region requires consideration of the placement site and angle based on anatomical characteristics.

An anatomic variation of the trapezius muscle in a Korean: the cleido-occipitalis cervicalis.

A variation of the trapezius muscle was observed in a Korean female adult cadaver during routine student dissection. The lateral, upper three-fourths of the descending portion of the trapezius muscle were separated from the remainder of the muscle. This single, isolated bundle fused above the insertion of the midpoint of the clavicle, and attached to the clavicle as a separate tendon. The remaining descending portion inserted into the clavicle and scapula as usual. This abnormal muscle bundle is considered as a variant of the cleido-occipitalis cervicalis, and formation of this variation is discussed based on the embryological development of the relative muscular structures.