The depressor anguli oris (DAO) muscle is a thin, superficial muscle located below the corner of the mouth. It is the target for botulinum neurotoxin (BoNT) injection therapy, aimed at treating drooping mouth corners. Hyperactivity of the DAO muscle can lead to a sad, tired, or angry appearance in some patients. However, it is difficult to inject BoNT into the DAO muscle because its medial border overlaps with the depressor labii inferioris and its lateral border is adjacent to the risorius, zygomaticus major, and platysma muscles. Moreover, a lack of knowledge of the anatomy of the DAO muscle and the properties of BoNT can lead to side effects, such as asymmetrical smiles. Anatomical-based injection sites were provided for the DAO muscle, and the proper injection technique was reviewed. We proposed optimal injection sites based on the external anatomical landmarks of the face. The aim of these guidelines is to standardize the procedure and maximize the effects of BoNT injections while minimizing adverse events, all by reducing the dose unit and injection points.

The mentalis muscle is a paired muscle originating from the alveolar bone of the mandible. This muscle is the main target muscle for botulinum neurotoxin (BoNT) injection therapy, which aims to treat cobblestone chin caused by mentalis hyperactivity. However, a lack of knowledge on the anatomy of the mentalis muscle and the properties of BoNT can lead to side effects, such as mouth closure insufficiency and smile asymmetry due to ptosis of the lower lip after BoNT injection procedures. Therefore, we have reviewed the anatomical properties associated with BoNT injection into the mentalis muscle.An up-to-date understanding of the localization of the BoNT injection point according to mandibular anatomy leads to better injection localization into the mentalis muscle. Optimal injection sites have been provided for the mentalis muscle and a proper injection technique has been described. We have suggested optimal injection sites based on the external anatomical landmarks of the mandible. The aim of these guidelines is to maximize the effects of BoNT therapy by minimizing the deleterious effects, which can be very useful in clinical settings.

The dog frontal sinus may represent an alternative model dental implant research; its topographical resemblance to the maxillary sinus renders it a potentially favorable experimental environment. The aim of this study was thus to elucidate the anatomical configuration of the canine frontal sinus and histological characteristics, and to determine whether it could be a new canine experimental model for dental implant research. Twenty-four sides of canine frontal bones were harvested. The distance from the nasion to the emerging point of the lateral aspect of the canine frontal sinus was measured with the aid of Lucion software. The thicknesses of the canine frontal sinus wall were measured, and the two specimens stained with hematoxylin and eosin. The mean distance from the nasion to the emerging point of the lateral aspect of the canine frontal sinus was 16.0 mm. The mean thicknesses of the canine frontal bone at 3, 6, 9, 12, and 15 mm lateral to the midsagittal plane were 2.3, 2.7, 3.2, 3.8, and 3.7 mm, respectively. The canine frontal sinus was lined with pseudostratified ciliated columnar epithelium. These data suggest that the canine frontal sinus is a suitable alternative to the canine maxillary sinus as a model for studying various sinus augmentation protocols.
Animals ; Dental Implants ; Dogs ; Eosine Yellowish-(YS) ; Epithelium ; Frontal Bone ; Frontal Sinus* ; Hematoxylin ; Maxillary Sinus ; Models, Theoretical*

Sihler's staining allows visualization of the nerve distribution within soft tissues without extensive dissection and does not require slide preparation, unlike traditional approaches. This technique can be applied to the mucosa, muscle, and organs that contain myelinated nerve fibers. In particular, Sihler's technique may be considered the best tool for observing nerve distribution within skeletal muscles. The intramuscular distribution pattern of nerves is difficult to observe through manual manipulation due to the gradual tapering of nerves toward the terminal end of muscles, so it should be accompanied by histological studies to establish the finer branches therein. This method provides useful information not only for anatomists but also for physiologists and clinicians. Advanced knowledge of the nerve distribution patterns will be useful for developing guidelines for clinicians who perform operations such as muscle resection, tendon transplantation, and botulinum toxin injection. Furthermore, it is a useful technique to develop neurosurgical techniques and perform electrophysiological experiments. In this review, Sihler's staining technique is described in detail, covering its history, staining protocol, advantages, disadvantages, and possible applications. The application of this technique for determining the arterial distribution pattern is also described additionally in this study.
Anatomists ; Arteries ; Botulinum Toxins ; Humans ; Mucous Membrane ; Muscle, Skeletal ; Muscles ; Nerve Fibers, Myelinated ; Tendons ; Transplants

Recently, invasive infections with the human pathogen Streptococcus dysgalactiae subspeciesequisimilis (SDSE) have increased around the globe. Typing of the emm gene of SDSE, which encodes a virulence factor (M protein), has provided important information. Here, we report two cases of invasive SDSE infection that presented with endocarditis and bacteremia, and their emm gene types.
Bacteremia ; Endocarditis ; Humans ; Streptococcus* ; Virulence

Recently, invasive infections with the human pathogen Streptococcus dysgalactiae subspeciesequisimilis (SDSE) have increased around the globe. Typing of the emm gene of SDSE, which encodes a virulence factor (M protein), has provided important information. Here, we report two cases of invasive SDSE infection that presented with endocarditis and bacteremia, and their emm gene types.
Bacteremia ; Endocarditis ; Humans ; Streptococcus* ; Virulence

The digastric muscle is located in the suprahyoid region which consists of anterior belly, intermediate tendon and posterior belly. This muscle is an important landmark when performing an operation of submental and upper neck region. Previous researches have reported about variations of the anterior and posterior belly of digastric muscle. However, there are few studies about the general morphology of the digastric muscle and the relationship with surrounding muscles. The purpose of this study was to analyze the morphology of the anterior belly of digastric muscle and confirm the topographic relationship between the digastric muscle and the stylohyoid muscle of Korean. Thirty-four cadavers (21 males, 13 females; mean age 65 years; range 24~89 years) were used in this study. The skin, subcutaneous tissues, superficial fascia and platysma were removed and a detailed dissection was performed, with extreme care being taken not to damage underlying the muscles of submental and upper neck region. After the dissections, all specimens were sketched and photographed. In 8 specimens, we observed the accessory bellies of the anterior belly of digastric muscle. We classified the accessory bellies into the crossover type (five specimens, 14.7%) that cross the mandibular raphe and unilateral type (three specimens, 8.82%). The findings resulting from observation of the anatomical relationship between the posterior belly of digastric and stylohyoid muscles, the posterior belly of digastric muscle perforated the stylohyoid muscle in 32 cases (65%) out of 49 sides. This case was subdivided into the belly of the stylohyoid muscle lean to the lateral (twenty-one specimens, 42.9%) or medial side (eleven specimens, 22.4%) of the posterior belly of digastric muscle. In 17 specimens (35%), the stylohyoid muscle existed on the medial side of the posterior belly of digastric muscle.
Anatomic Variation ; Cadaver ; Humans ; Male ; Muscles ; Neck ; Skin ; Subcutaneous Tissue ; Tendons

Hypernatremia is a rare cause of rhabdomyolysis. Here, we report a case of hypernatremia-induced rhabdomyolysis in a patient with meningioma involving the pituitary gland. A 61-year-old male was admitted for decreased mentality and poor oral intake. He had undergone an operation for meningioma 10 years prior. At admission, he appeared lethargic and severely dehydrated with an initial sodium level of 178 mEq/L. Hypernatremia remained persistent despite massive hydration and the serum creatine phosphokinase level was 18,047 U/L after 3 days. Bone scintigraphy also showed findings consistent with rhabdomyolysis. Brain magnetic resonance imaging revealed extensive masses involving the pituitary gland and an intranasal biopsy confirmed meningioma. Polyuria, and low anti-diuretic hormone levels supported the diagnosis of central diabetes insipidus-induced hypernatremia. Desmopressin was administered intranasally and the patient's serum sodium and muscle enzyme levels were normalized.
Biopsy ; Brain ; Creatine Kinase ; Deamino Arginine Vasopressin ; Diabetes Insipidus ; Diagnosis ; Humans ; Hypernatremia ; Magnetic Resonance Imaging ; Male ; Meningioma* ; Middle Aged ; Pituitary Gland* ; Polyuria ; Radionuclide Imaging ; Rhabdomyolysis* ; Sodium

Rheumatoid arthritis is associated with an increased risk of hematological malignancy as a result of the RA itself or its treatment. We report here on an unusual case of a 55-year-old female with long-standing rheumatoid arthritis and who was treated with low dose methotrexate and hydrochloroquine. She was diagnosed with chronic myelogenous leukemia that manifested with severe thrombocytosis and basophilia, and this was treated with imatinib mesylate. After 6 months, she achieved a complete cytogenetic response of the CML and a complete resolution of all the RA symptoms without DMARDs.
Antirheumatic Agents ; Arthritis, Rheumatoid ; Benzamides ; Cytogenetics ; Female ; Hematologic Neoplasms ; Humans ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive ; Mesylates ; Methotrexate ; Middle Aged ; Piperazines ; Pyrimidines ; Thrombocytosis ; Imatinib Mesylate

BACKGROUND/AIMS: To compare the frequency of metabolic syndrome (MetS) and magnitude of insulin resistance, measured by the homeostatic model assessment of insulin resistance (HOMA-IR), between South Korean women with rheumatoid arthritis (RA) and healthy subjects, and to evaluate risk factors for MetS and increased HOMA-IR in patients with RA. METHODS: In a cross-sectional setting, 84 female patients with RA and 109 age-matched healthy female subjects were consecutively recruited at a university-affiliated rheumatology center in South Korea. MetS was defined according to the Third Report of the National Cholesterol Education Program's Adult Treatment Panel (NCEP-ATP III) 2004 criteria. RESULTS: The frequency of MetS did not differ significantly between patients with RA (19%) and healthy subjects (15.6%, p = 0.566), although patients with RA had a higher HOMA-IR compared with healthy subjects (p < 0.001). Patients with RA met the NCEP-ATP III 2004 criteria for high blood pressure more often than healthy subjects (44% vs. 19.3%, p < 0.001), and low high density lipoprotein cholesterol was more prevalent in healthy subjects (33%) than in patients with RA (14.3%, p = 0.004). Although no obvious risk factors for the presence of MetS were identified in patients with RA, higher serum C-reactive protein and disease activity score assessed using the 28-joint count for swelling and tenderness-erythrocyte sedimentation rate significantly contributed to a higher HOMA-IR. CONCLUSIONS: Despite their increased insulin resistance, South Korean women with RA did not have a significantly higher frequency of MetS compared with that in healthy subjects.
Adult ; Aged ; Arthritis, Rheumatoid/diagnosis/*epidemiology ; Biological Markers/blood ; Case-Control Studies ; Chi-Square Distribution ; Cross-Sectional Studies ; Female ; Humans ; Insulin Resistance ; Linear Models ; Logistic Models ; Metabolic Syndrome X/blood/diagnosis/*epidemiology ; Middle Aged ; Multivariate Analysis ; Odds Ratio ; Prevalence ; Republic of Korea/epidemiology ; Risk Assessment ; Risk Factors ; Sex Factors ; Young Adult