Tongue Growth during Prenatal Development in Korean Fetuses and Embryos

BACKGROUND: Prenatal tongue development may affect oral-craniofacial structures, but this muscular organ has rarely been investigated. METHODS: In order to document the physiology of prenatal tongue growth, we histologically examined the facial and cranial base structures of 56 embryos and 106 fetuses. RESULTS: In Streeter's stages 13-14 (fertilization age [FA], 28 to 32 days), the tongue protruded into the stomodeal cavity from the retrohyoid space to the cartilaginous mesenchyme of the primitive cranial base, and in Streeter's stage 15 (FA, 33 to 36 days), the tongue rapidly swelled and compressed the cranial base to initiate spheno-occipital synchondrosis and continued to swell laterally to occupy most of the stomodeal cavity in Streeter's stage 16-17 (FA, 37 to 43 days). In Streeter's stage 18-20 (FA, 44 to 51 days), the tongue was vertically positioned and filled the posterior nasopharyngeal space. As the growth of the mandible and maxilla advanced, the tongue was pulled down and protruded anteriorly to form the linguomandibular complex. Angulation between the anterior cranial base (ACB) and the posterior cranial base (PCB) was formed by the emerging tongue at FA 4 weeks and became constant at approximately 124degrees-126degrees from FA 6 weeks until birth, which was consistent with angulations measured on adult cephalograms. CONCLUSIONS: The early clockwise growth of the ACB to the maxillary plane became harmonious with the counter-clockwise growth of the PCB to the tongue axis during the early prenatal period. These observations suggest that human embryonic tongue growth affects ACB and PCB angulation, stimulates maxillary growth, and induces mandibular movement to achieve the essential functions of oral and maxillofacial structures.

National Academy of Medicine of Korea Celebrates Its 10th Anniversary

No abstract available.

Neural Substrates of Hanja (Logogram) and Hangul (Phonogram) Character Readings by Functional Magnetic Resonance Imaging

The two basic scripts of the Korean writing system, Hanja (the logography of the traditional Korean character) and Hangul (the more newer Korean alphabet), have been used together since the 14th century. While Hanja character has its own morphemic base, Hangul being purely phonemic without morphemic base. These two, therefore, have substantially different outcomes as a language as well as different neural responses. Based on these linguistic differences between Hanja and Hangul, we have launched two studies; first was to find differences in cortical activation when it is stimulated by Hanja and Hangul reading to support the much discussed dual-route hypothesis of logographic and phonological routes in the brain by fMRI (Experiment 1). The second objective was to evaluate how Hanja and Hangul affect comprehension, therefore, recognition memory, specifically the effects of semantic transparency and morphemic clarity on memory consolidation and then related cortical activations, using functional magnetic resonance imaging (fMRI) (Experiment 2). The first fMRI experiment indicated relatively large areas of the brain are activated by Hanja reading compared to Hangul reading. The second experiment, the recognition memory study, revealed two findings, that is there is only a small difference in recognition memory for semantic transparency, while for the morphemic clarity was much larger between Hanja and Hangul. That is the morphemic clarity has significantly more effect than semantic transparency on recognition memory when studies by fMRI in correlation with behavioral study.

Anterior Commissure - Posterior Commissure Revisited

OBJECTIVE: The anterior commissure (AC) and posterior commissure (PC) are the two distinct anatomic structures in the brain which are difficult to observe in detail with conventional MRI, such as a 1.5T MRI system. However, recent advances in ultra-high resolution MRI have enabled us to examine the AC and PC directly. The objective of the present study is to standardize the shape and size of the AC and PC using a 7.0T MRI and to propose a new brain reference line. MATERIALS AND METHODS: Thirty-four, 21 males and 13 females, healthy volunteers were enrolled in this study. After determining the center of each AC and PC, we defined the connection of these centers as the central intercommissural line (CIL). We compared the known extra- and intra-cerebral reference lines with the CIL to determine the difference in the angles. Additionally, we obtained horizontal line from flat ground line of look front human. RESULTS: The difference in angle of the CIL and the tangential intercommissural line (TIL) from the horizontal line was 8.7 +/- 5.1 (11 +/- 4.8) and 17.4 +/- 5.2 (19.8 +/- 4.8) degrees in males and females, respectively. The difference in angle between the CIL and canthomeatal line was 10.1 in both male and female, and there was no difference between both sexes. Likewise, there was no significant difference in angle between the CIL and TIL between both sexes (8.3 +/- 1.1 in male and 8.8 +/- 0.7 in female). CONCLUSION: In this study, we have used 7.0T MRI to define the AC and PC quantitatively and in a more robust manner. We have showed that the CIL is a reproducible reference line and serves as a standard for the axial images of the human brain.

Segmentation of Cerebral Gyri in the Sectioned Images by Referring to Volume Model

Authors had prepared the high-quality sectioned images of a cadaver head. For the delineation of each cerebral gyrus, three-dimensional model of the same brain was required. The purpose of this study was to develop the segmentation protocol of cerebral gyri by referring to the three-dimensional model on the personal computer. From the 114 sectioned images (intervals, 1 mm), a cerebral hemisphere was outlined. On MRIcro software, sectioned images including only the cerebral hemisphere were volume reconstructed. The volume model was rotated to capture the lateral, medial, superior, and inferior views of the cerebral hemisphere. On these four views, areas of 33 cerebral gyri were painted with colors. Derived from the painted views, the cerebral gyri in sectioned images were identified and outlined on the Photoshop to prepare segmented images. The segmented images were used for production of volume and surface models of the selected gyri. The segmentation method developed in this research is expected to be applied to other types of images, such as MRIs. Our results of the sectioned and segmented images of the cadaver brain, acquired in the present study, are hopefully utilized for medical learning tools of neuroanatomy.

A Proposal of New Reference System for the Standard Axial, Sagittal, Coronal Planes of Brain Based on the Serially-Sectioned Images

Sectional anatomy of human brain is useful to examine the diseased brain as well as normal brain. However, intracerebral reference points for the axial, sagittal, and coronal planes of brain have not been standardized in anatomical sections or radiological images. We made 2,343 serially-sectioned images of a cadaver head with 0.1 mm intervals, 0.1 mm pixel size, and 48 bit color and obtained axial, sagittal, and coronal images based on the proposed reference system. This reference system consists of one principal reference point and two ancillary reference points. The two ancillary reference points are the anterior commissure and the posterior commissure. And the principal reference point is the midpoint of two ancillary reference points. It resides in the center of whole brain. From the principal reference point, Cartesian coordinate of x, y, z could be made to be the standard axial, sagittal, and coronal planes.

Over-expression of MMP-3 in the fissured tissue of cleft lip and palate

OBJECTIVE: In order to elucidate the retrogressive degeneration of orofacial cleft, the fissured tissues of prenatal and postnatal cleft lip and palate were examined by histological and immunohistochemical methods. DESIGN: Totally 42 cases of prenatal (n=17) and postnatal (n=25) cleft lip and/or palate were examined in comparison with 10 cases of normal lip and oral mucosa using immunohistochemical stainings of MMP-3, MMP-9, MMP-10, cathepsin G, PCNA, E-cadherin, TGase 2, HSP-70, vWF, and VEGF. MAIN OUTCOME MEASURES: In the fissured tissue the sebaceous glands were strongly positive for PCNA and grew into the underlying fibromuscular tissue (24/42). Some hyperplastic sebaceous glands of prenatal cleft lip produced infundibular follicular cyst (9/17). The skin and mucosal epithelia from the postnatal cleft lip and palate (10/25) showed severe basal hyperplasia (11/25) and melanocyte infiltration (7/25). RESULTS: The immunostaining of MMP-3 and HSP-70 were strongly positive in the hyperplastic sebaceous glands and nearby atrophying muscle bundles of the fissured tissue, while MMP-9, MMP-10, and cathepsin G were almost negative. The immunoreactions of the other antibodies used in this study were similar between in the fissured tissues and in the normal controls. CONCLUSIONS: These data suggest that the over-expression of MMP-3 is closely related to the sebaceous gland hyperplasia, epithelial dysplasia, and the muscle degeneration, and that the over-expression of MMP-3 in the fissured tissue may continuously aggravate the cleft condition in the later life.

Two Cases of Congenital Toxoplasmosis Diagnosed by Polymerase Chain Reaction

The diagnosis of congenital toxoplasmosis may be difficult due to diversity of symptoms. However, the diagonosis is very important for treatment and determination of the prognosis of infected infants. We recently experienced two cases of congenital toxoplasmosis. The first case was suspected as congenital infection with hydrocephalus that was detected by prenatal ultrasonography. Postnatal evaluation revealed positive latex agglutination and ELISA IgG antibodies, and negative ELISA IgM antibodies for Toxoplasma gondii. Histologic examination of the biopsied brain tissue revealed microcalcification. The second case presented with jaundice and intraventricular hemorrhage, and serological evaluation revealed positive latex agglutination and ELISA IgG antibodies, and negative ELISA IgM antibodies for T. gondii. The mother was positive for ELISA IgM antibodies as well as for latex agglutination and ELISA IgG antibodies. In the blood and CSF of both infants as well as in the blood of their mothers, Toxoplasma specific B1 gene was detected by polymerase chain reaction and Southern blot analysis. Based on these results, we have confirmed two cases of congenital toxoplasmosis whose presenting symptoms were hydrocephalus, seizure, or jaundice, and these cases represent the first series of congenital toxoplasmosis diagnosed in Korea by polymerase chain reaction.

Two Cases of Congenital Toxoplasmosis Diagnosed by Polymerase Chain Reaction

The diagnosis of congenital toxoplasmosis may be difficult due to diversity of symptoms. However, the diagonosis is very important for treatment and determination of the prognosis of infected infants. We recently experienced two cases of congenital toxoplasmosis. The first case was suspected as congenital infection with hydrocephalus that was detected by prenatal ultrasonography. Postnatal evaluation revealed positive latex agglutination and ELISA IgG antibodies, and negative ELISA IgM antibodies for Toxoplasma gondii. Histologic examination of the biopsied brain tissue revealed microcalcification. The second case presented with jaundice and intraventricular hemorrhage, and serological evaluation revealed positive latex agglutination and ELISA IgG antibodies, and negative ELISA IgM antibodies for T. gondii. The mother was positive for ELISA IgM antibodies as well as for latex agglutination and ELISA IgG antibodies. In the blood and CSF of both infants as well as in the blood of their mothers, Toxoplasma specific B1 gene was detected by polymerase chain reaction and Southern blot analysis. Based on these results, we have confirmed two cases of congenital toxoplasmosis whose presenting symptoms were hydrocephalus, seizure, or jaundice, and these cases represent the first series of congenital toxoplasmosis diagnosed in Korea by polymerase chain reaction.

The Morphological Change of Iris and Ciliary Body in the Korean Fetal Eyes according to Gestational Age

PURPOSE: This study was performed to investigate the morphological change of the iris and ciliary body of human eyes during fetal period. METHODS: Under the Registry of Congenital malformation, fetuses were supplied by the Department of Pathology of Seoul National University. We selected 81 eyes enrolled with the gestational age between 8 and 40 weeks, and examined under light microscope. RESULTS: The development of iris and ciliary body began from 12 weeks. During the gestational age 15-18 weeks, marginal sinus and the fold of iris and ciliary body were formed. At the gestational age 18 weeks, the iris sphincter located in front of marginal sinus was certainly distinguished, and the vessels of ciliary body formed. During the gestational age 19-22 weeks the minor folds of ciliary body were formed between the original it. During the gestational age 23-27 weeks marginal sinus was being diminished and dilator muscle was seen. During the gestational age 28-30 weeks the dilator muscle of iris was certainly developed and the longitudinal and circular muscle of ciliary body were distinguished. During the gestational age 34-40 weeks the adultlike appearance of the iris and ciliary body became apparent. CONCLUSIONS: The mesenchymal cells located in the anterior rim of optic cup began to develop after the gestational age 12 weeks. If the develpment of the iris and ciliary body was arrested around the gestational age 15-22 weeks, the congenital malformation of the iris and ciliary body could appear.

Prospectives of Research Institute of Healthcare Policy, Korean Medical Association

No abstract available.

Unusual Perirenal Location of a Tailgut Cyst

The authors describe a case in which a tailgut cyst occurred at an unusual location in a 22-year-old woman referred for abdominal discomfort and urinary frequency. The left abdomen contained a palpable mass, found at imaging studies to be a homogeneous, unilocular and cystic, and anterior to the left kidney. After surgical excision, it was shown to be a tailgut cyst.

Sudden Unexpected Death in Infancy: Analysis of 34 Cases Including 13 Autopsies

PURPOSE: The purpose of this study is to analyze the epidemiologic characteristics of sudden unexpected death in infancy and to evaluate the importance of postmortem autopsy. METHODS: We reviewed, retrospectively, medical records of 34 infants admitted to Kangnam General Hospital from January 1987 to December 2001 because of sudden unexpected death. We investigated the cause of death through medical history, death scene examination, autopsy findings, acylcarnitine and organic acid analysis. RESULTS: Among the total 34 infants, 18 were male(52.9%) and 16 were female(47.1%). Thirty infants(88%) were below the six months of age. Winter was the most affected season(38.2%). Eighteen infants(52.9%) died between 6 and 12AM. The prone sleeping position was observed more frequently than the supine position at death; nine cases in the prone position, six cases in the supine position. The cause of death of 23 cases could not be found by only history and death scene examination. Autopsy was done in 13 cases. Seven cases of them were thought to be SIDS. In six cases, we explained the cause of death with autosy findings. They were an endocardial fibroelastosis, a nesidioblastosis, a subdural hematoma, a bronchopneumonia and two fatty changes of liver. Metabolic screening tests performed in three cases to rule out metabolic disorder since 2000 were all normal. CONCLUSION: We concluded that autopsy and metabolic screening test should be performed to find out the cause of death in sudden unexpected death in infancy.

A Case of Solid and Papillary Epithelial Neoplasm of Pancreas in a Young Adolescent / 대한소아소화기영양학회지

Solid and papillary epithelial neoplasm (SPEN) of the pancreas is an uncommon tumor and is found predominantly in young females. The most common clinical presentation is an abdominal mass. The tumor has a low grade malignant potential and complete removal is the treatment of choice. We report a case of SPEN in a 13-year-old girl who presented with abdominal pain and increasing size of an abdominal mass after abdominal trauma. CT and sonographic findings showed a well-demarcated mass in the pancreas tail with solid and cystic portion. She got a distal pancreatectomy and pathologic finding was SPEN of pancreas.

A Case of Hereditary Motor and Sensory Neuropathy Type III

Hereditary motor and sensory neuropathy type III, which is also known as Dejerine-Sottas disease, is a severe demyelinating polyneuropathy which presents from birth or infancy, and is sometimes presented as a hypotonic or floppy infant. The disease is inherited autosomal recessively and includes clinical findings of generalized muscle weakness and atrophy, with the greatest severity in distal limb muscles, areflexia, and sensory loss. The disease is characterized histologically by segmental demyelination, remyelination of the peripheral nerves, and onion bulb formations. We experienced a 12-month-old girl with delayed development, frequent respiratory infection and pes cavus. We report this case with a review of related literature.

Morphologic Changes of Anterior Chamber Angle and Trabecular Meshwork According to Embryonic Age in Human Fetal Eyes

PURPOSE: To investigate the morphologic changes of anterior chamber angle and trabecular meshwork during development in human fetal eyes, 77 eyes was enrolled in this study. METHODS: The sequential development of iridocorneal angle and trabecular meshwork were examined using light microscopy in 77 eyes with a gestational age ranged from 7 to 40 weeks. RESULTS: It was found that the presence of openings in the anterior chamber angle lining and aqueous humor drainage was effective by 20~22 weeks of fetal life and intercellular gaps become larger and more frequent as development progresses. During the gestational age(28~30 week), the anterior ahamber was located at the middle of the trabecular meshwork. During the gestational age(32~38 week), the intertra-becular space was widen with the apparent presence of the Schlemm's canal. CONCLUSIONS: The arrest or abnormal differetiation during the gestational period may cause the dysfunction of aqueous humor outflow, to develop congenital glaucoma.

A Case of Mesenchymal Hamartoma Associated with Biliary Atresia / 대한소아소화기영양학회지

Mesenchymal hamartoma is an uncommon benign tumor usually found in childhood, especially during the first two years of life. The tumor consists of a solid component and multiple cyst. Without treatment, these lesions can grow to an enormous size. We experienced a case of mesenchymal hamartoma which was found incidentally, in a 8 month old girl who had ascending cholangitis after Kasai operation due to biliary atresia. On abdominal ultrasonography and CT, there was a well-defined homogeneous small echogenic mass in the right lobe of the liver with cirrhosis. Five months later, she underwent liver transplantation. Gross picture of the resected liver showed a dark greenish pigmented solid mass in the right lobe of the cirrhotic liver. Microscopic findings showed reactive mesenchyma and epithelial overgrowth.

Improved Technique of Digoxigenin Labeled RNA in situ Hybridization

BACKGROUND: A practical RNA in situ hybridization method using digoxigenin labeled RNA probes is described in order to evaluate the technical difficulties and problems in RNA in situ hybridization. METHODS: The paraffin sections, routinely processed in the Pathology Laboratory, were tested for the possibility of RNA in situ hybridization instead of the RNase free paraffin sections, fixed in 4% paraformaldehyde and prepared using RNase protection procedures. RESULTS: Most of the paraffin sections, fixed in 10% neutral formalin solution in fresh condition, showed relatively good reaction of RNA in situ hybridization, although the necrotic tissue and autopsy specimens showed poor reaction of RNA in situ hybridization. A refixation procedure using a 4% paraformaldehyde solution was evaluated for optimal expression of mRNA in the paraffin sections. CONCLUSION: The treatment of 4% paraformaldehyde before the treatment of proteinase K showed better in situ hybridization than did the treatment of 4% paraformaldehyde after the treatment of proteinase K. Also a new Polymerase Chain Reaction (PCR)-based method of RNA probe production showed consistently good results.

Cytologic Features and Distribution of Primary Sites of Malignant Cells in Cerebrospinal Fluid / 대한세포병리학회지

Cytologic evaluation of cerebrospinal fluid(CSF) is an effective mean for diagnosing many disorders involving the central nervous systems(CNS). One of the most important reasons for cytologic examination of CSF is to detect metastatic or primary neoplasms of the CNS. We did a retrospective study of 1,438 CSF specimens obtained between 1992 and 1996. A total of 1,205 adult and 233 pediatric CSF specimens from 947 patients were accessed at the Department of Pathology of Seoul National University Hospital and Children's Hospital, respectively. Among 1,438 CSF cytology specimens, 169 cases(11.8%, 77 patients) including 135 adult cases(59 patients) and 34 pediatric cases(18 patients) were positive for malignant cells. Diagnoses included 60 metastatic carcinomas(adult, 60; pediatric, 0); 46 malignant lymphomas(adult, 44; pediatric, 2); 21 leukemias(adult, 20; pediatric, 1); 4 retinoblastomas(adult, 0; pediatric 4); 2 rhabdomyosarcomas(adult, 0; pediatric, 2); 1 multiple myeloma(adult, 1; pediatric, 0), and 35 primary CNS neoplasms(adult, 10; pediatric, 25). The most commonly identified metastatic carcinomas in adults were adenocarcinoma. Their primary sites were the lung, gastrointestinal tract, and breast in order of frequency. The most common primary CNS neoplasm in children was medulloblastoma.

Diagnosis of Duchenne/Becker Muscular Dystrophy: Clinical and Moleculargenetic Characteristics

PURPOSE: Duchenne/Becker muscular dystrophy (DMD/BMD) is an X-linked recessive disease caused by the mutation of dystrophin gene. Since the majority of mutations are deletions, recent diagnosis is made by the moleculargenetic tools. The authors summarized the clinical characteristics, and analyzed the moleculargenetic and immunohistochemical characteristics of DMD/BMD. METHODS: We reviewed the clinical and laboratory findings of 69 patients diagnosed as DMD/BMD from 1989 to 2000. Multiplex PCR using 26 primer sets was performed on 34 cases, and immunohistochemical staining using dystrophin antibody was done on 5 cases. Mutation profile and phenotype-genotype relationship were analyzed. RESULTS: 1) Mean age of onset was 3 years and 6 months. The presenting symptoms were motor weakness of the lower extremities, incidentally found elevated hepatic enzyme level, abnormal gait and motor developmental delay. Forty one percent had history of motor developmental delay, and most patients showed pseudohypertrophic calf muscles. Mean serum creatine kinase level was 11,232IU/L, and 44% revealed abnormal electrocardiogram. 2) All of the 63 cases showed typical histological findings of muscular dystrophy. Of the 5 cases with immunohistochemical staining, 2 showed complete (DYS1, 2 and 3) and 3 showed partial (DYS3) absence pattern. 3) Of the 34 cases on which multiplex PCR was performed, 14 showed deletions, and 11 of them had deletions between exon 44 and 55. CONCLUSION: Since the deletions were detected in less than 50% of the patients with multiplex PCR, tools for dystrophin protein expression must be combined for the correct diagnosis. Considering the invasiveness of muscle biopsy, we conclude immunohistochemistry should be followed in the cases with negative results in multiplex PCR, although moleculargenetic study is the primary diagnostic tool.