The hepatic hemopoiesis in intrauterine lifeis predominently erythropoiesis,and the erythroblasts undergo the differentiation process finally to form reticulocytes.In this syudy, the development of erythropoiesis in human fetal liver was observed using transmission electron microscope. The immature erythroblasts were more prominent in earlier fetal liver and proliferated rather than went through final differentiation process. The erythroblasts of different differentiation stages exhibited apoptosis in addition to the normal differentiation process. The nuclei of acidophilic erythroblasts were removed by the excessive condensation and dissociation of nuclei from the cytoplasm or by the displacement of nuclei to one side of the cell with deformation of nuclei. The deformed nuclei restored the round shape after the completion of enucleation and engulfed by hepatocytes and Kupffer cells. Two types of erythroblast islands were present in hepatic plate by the differentiation stages of erythroblasts, id est, islands of the same and the different differentiation stages. And several erythroblasts and enucleated nuclei were included in hepatocytes, intrahepatic macrophages and Kupffer cells, and the intrahepatic macrophages resembling Kupffer cell could be suggested to be originated from the Kupffer cell. But there was no morphological evidence of phagocytosis of erythroblasts and nuclei by these cells. In summary, human fetal hepatic erythropoiesis occurred by forming erythroblastic islands and some erythroblasts proceeded to apoptosis during the differentiation. Hepatocytes and macrophages were present in close relation to erythroblast islands and were suggested to influence the development and differentiation of erythroblasts.
Apoptosis ; Cytoplasm ; Erythroblasts* ; Erythropoiesis ; Hepatocytes ; Humans* ; Islands ; Kupffer Cells ; Liver* ; Macrophages ; Phagocytosis

Purpose: The first-line antithyroid drug for children and adolescents with Graves’ disease (GD) is methimazole (MMI). This study evaluated the relationship between the initial MMI dose and the clinical course of GD after treatment. Methods: We studied the efficacy of the initial MMI dose and the relationship between the initial MMI dose and adverse events (AEs). We retrospectively enrolled 22 males and 77 females and divided those subjects into 3 groups according to the initial dose of MMI: <0.4 mg/kg/day (group A; n=32); 0.4–0.7 mg/kg/day (group B; n=39); and >0.7 mg/kg/day (group C; n=28). Results: The mean time to the normalization of free thyroxine (fT4) levels upon initial treatment was 5.64, 8.61, and 7.98 weeks in groups A, B, and C, respectively (P=0.116). The incidence of liver dysfunction, neutropenia, and skin rash was 12.5%, 20.5%, and 42.9% in groups A, B, and C, respectively (P=0.018). Neutropenia, as a severe AE, was absent in group A, but its prevalence was 7.7% in group B and 21.4% in group C (P=0.015). When comparing only groups B and C, the incidences of liver dysfunction and neutropenia were higher in group C (P=0.04 and P=0.021, respectively). Conclusion The mean time to the normalization of fT4 levels did not differ among the 3 groups, but the incidence of AEs was higher in the groups that received high MMI doses. High doses of MMI (>0.7 mg/kg/day) should be reconsidered as an initial treatment for children and adolescents with GD.

Purpose: The first-line antithyroid drug for children and adolescents with Graves’ disease (GD) is methimazole (MMI). This study evaluated the relationship between the initial MMI dose and the clinical course of GD after treatment. Methods: We studied the efficacy of the initial MMI dose and the relationship between the initial MMI dose and adverse events (AEs). We retrospectively enrolled 22 males and 77 females and divided those subjects into 3 groups according to the initial dose of MMI: <0.4 mg/kg/day (group A; n=32); 0.4–0.7 mg/kg/day (group B; n=39); and >0.7 mg/kg/day (group C; n=28). Results: The mean time to the normalization of free thyroxine (fT4) levels upon initial treatment was 5.64, 8.61, and 7.98 weeks in groups A, B, and C, respectively (P=0.116). The incidence of liver dysfunction, neutropenia, and skin rash was 12.5%, 20.5%, and 42.9% in groups A, B, and C, respectively (P=0.018). Neutropenia, as a severe AE, was absent in group A, but its prevalence was 7.7% in group B and 21.4% in group C (P=0.015). When comparing only groups B and C, the incidences of liver dysfunction and neutropenia were higher in group C (P=0.04 and P=0.021, respectively). Conclusion The mean time to the normalization of fT4 levels did not differ among the 3 groups, but the incidence of AEs was higher in the groups that received high MMI doses. High doses of MMI (>0.7 mg/kg/day) should be reconsidered as an initial treatment for children and adolescents with GD.

This study aimed to analyze trends in research on depression among medical students in Korea and to conduct a meta-analysis to determine the average correlation coefficients between depression and related variables. In total, 38 quantitative studies (four theses and 34 journal articles) published between January 1995 and February 2023 were analyzed according to publication year, subjects, analysis methods, and measurement tools. Among them, 15 studies that provided numerical information on the relationships between depression and variables such as self-esteem, social support, grade point average (GPA), stress, and academic stress were selected for meta-analysis. The main findings of this study were as follows. First, quantitative research on depression among medical students began in earnest in 2009, and cross-sectional studies targeting first-year and second-year medical students were the most prevalent. Furthermore, the most commonly used analysis method was difference testing, and the Beck Depression Inventory was the most frequently used measurement tool. Second, the mean correlation coefficients between depression and stress, self-esteem, social support, academic stress, and GPA were 0.534, 0.532, 0.465, 0.390, and 0.102, respectively. The results for self-esteem, stress, and academic stress showed substantial heterogeneity, while those for social support and GPA showed little heterogeneity. These findings suggest that educational interventions, such as social support improvement programs, are necessary to prevent depression among medical students.

BACKGROUND: Inhaled nitric oxide therapy causes selective pulmonary vasodilation in congenital heart diseases with pulmonary hypertension. However discontinuation of inhaled nitric oxide therapy may be complicated by abrupt life-threatening rebound pulmonary hypertension(RPH) The purpose of this study was to prevent by comparing group I(without RPH n=13) and group II(with RPH n=6) to determine the risk factors involved inthe development of the RPH. MATERIAL AND METHOD: Between Januarty 6, 1998 and April 14, 1999. we studied 19 consecutive children who were treated with inhaled nitric oxide for clinically significant pulmonary hypertension after an open heart surgery for congenital heart disease. the ratio of males and females was 12:7 ranging in age from 10 days to 6040 days(16 years) To identify the effects of nitric oxide between two groups we measured heart rate mean and systolic pulmonary arterial pressure mean and systolic systemic arterial pressure central venous pressure pH paO2/FiO2 and O2 saturation before and after the initiation and just before the withdrawal of the inhaled nitric oxide. RESULT: In 6 of 19 patients(32%) withdrawal of inhaled nitric oxide caused RPH. In the two groups inhaled nitrix oxide decreased in pulmonary arterial pressure(PAP) without decreasing the systemic arterial pressure(SAP) and increased PaO2/FiO2 Compared with patients who had no RPH(group I) patients who had RPH(group II) were older in age (1204+/-1688 versus 546+/-1654 days p<0.05) received less nitric oxide therapy(34+/-18 versus 67+/-46 hours p<0.05) has shorter weaning process(5+/-3 versus 15-13 hours p<0.05) and received lowerconcentration of initial nitric oxide supply(11+/-8 versus 17+/-8 ppm p>0.05) and lower concentration just before the withdrawal nitric oxide(4.2+/-2.6 versus 5.6+/-2.6 ppm, p>0.05) CONCLUSION: We speculate that older age shorter of nitric oxide therapy shorter weaning process are the risk factors of RPH.
Arterial Pressure ; Central Venous Pressure ; Child ; Female ; Heart Defects, Congenital ; Heart Diseases ; Heart Rate ; Humans ; Hydrogen-Ion Concentration ; Hypertension, Pulmonary* ; Male ; Nitric Oxide* ; Risk Factors ; Thoracic Surgery ; Vasodilation ; Weaning

A well-differentiated extraskeletal osteosarcoma is very rare, and only seven cases have been reported in the English language clinical literature. We report an additional case of this rare tumor. A 71-year-old man had noticed a mass in the left pubic area for ten years. A CT scan demonstrated the presence of a lobulated calcified mass within the soft tissue. A 5 cm-sized well-circumscribed mass was excised. Histologically the tumor was composed of mature collagenous tissue and bony trabeculae rimmed by osteoblasts. After 43 months, the tumor recurred at the same site and was re-excised. The re-excised tumor contained focal areas of higher cellularity and atypism. We believe that this is the first case of well-differentiated extraskeletal osteosarcoma reported in Korea.
Male ; Humans

PURPOSE: Tc-99m-MIBI (MIBI) and Tc-99m-Tetrofosmin (TF) are commonly used for scintimammography (SMM). We compared the diagnostic ability of SMM using Tc-99m-MIBI and Tc-99m-TF for the differential diagnosis of breast mass. MATERIALS AND METHODS: The study subjects were comprised of 123 breast lesions and 86 normal breasts of 114 patients who underwent SMM. Bilateral prone images and anterior supine images were obtained at 5 minutes and 1 or 3 hours after intravenous injection of 740 MBq of either MIBI or TF. Sizes of tumors were not significantly different between the MIBI and TF groups. First, two observers independently read the SMM without clinical information (1st interpretation), then read again with information about mass location (2nd interpretation). Sensitivity and specificity of each radiopharmaceutical for the diagnosis of breast cancer were evaluated in terms of image acquisition time, tumor size, and location. RESULTS: The SMM showed a good agreement between two observers for 1st and 2nd interpretation, except for TF SMM at 3 hr. For the first interpretation, the sensitivities at 5 min, 1 hr, and 3 hr were not significantly different between MIBI and TF SMM (81.6%, 80.0%, 60.9% in MIBI vs. 88.9%, 80.6%, 42.9% in TF), although the senstivities of 3 hr images were significantly lower than 5 min images in both MIBI and TF SMM. The specificity of TF at 5 min was superior to that of MIBI (81.5%, 90.0%, 82.9% in MIBI vs. 96.7%, 100%, 90.0% in TF, p<0.01 MIBI vs. TF at 5 min). For the second interpretation with information of mass location, the sensitivities at 3 hr images were significantly lower than 5 min images (86.8%, 86.7%, 78.3% in MIBI vs. 88.9%, 93.5%, 57.1% in TF) between MIBI and TF SMM. However, there was no significant difference in the specificity (60.0%, 53.8%, 75.0% for MIBI vs. 86.7%, 100%, 100% for TF). MIBI and TF SMM showed lower sensitivities for the tumors with less than 1 cm than tumors with more than 1 cm. However, the location of tumors did not influence the sensitivity and specificity between MIBI and TF SMM. CONCLUSION: The ability for the differential diagnosis of breast tumor is similar between MIBI and TF SMM, and delayed image is not necessary. TF may be better than MIBI considering the specificity of SMM without clinical information and labeling convenience.
Breast Neoplasms ; Breast* ; Diagnosis ; Diagnosis, Differential* ; Humans ; Injections, Intravenous ; Sensitivity and Specificity

PURPOSE: Periportal low attenuation, defined as a low attenuation rim around the portal vein and its branches which is seen on contrast material-enhanced CT scans, has been described in a variety of conditions. We tried to document that lymphatic obstruction is one of the major cause of periportal low attenuation. METHODS AND MATERIALS: We retrospectively analyzed 57 cases of periportal low attenuation on abdominal CT scans and also reviewed the surgical records in 32 cases. Lymph node enlargement in the hepatoduodenal ligament which is a main lymphatic channel from the liver were analyzed and calculated the ratio of the transeverse diameter between the inferior vena cava and the aorta at the level of right adrenal gland. After complete surgical interruption of the lymphatic drainage from the liver in a dog, follow up CT scans were obtained and correlated with pathologic findings. RESULTS: Fifty patients(88%) had underlying disease which could cause impairment of lymphatic drainage. Periportal low attenuation was identified in several clinical conditions, including surgical lymph node dissection, lymphadenopathy in the hepatoduodenal ligament, blunt trauma. In animal model, CT scan showed prominent periportal low attenuation at 5 days after surgery. Histologic examination revealed numerous dilated lymphatic vessels and a marked lymphedema in the connective tissues surrounding the portal vein and its major branches. CONCLUSION: One of the major.cuase of periportal low attenuation was impaired lymphatic drainage and periportal low attenuation corresponding to the numerous dilated lymphatic vessels and a marked lymphedema in the connective tissues surrounding the portal vein and its major branches.
Adrenal Glands ; Animals ; Aorta ; Connective Tissue ; Dogs ; Drainage ; Follow-Up Studies ; Ligaments ; Liver ; Lymph Node Excision ; Lymph Nodes ; Lymphatic Diseases ; Lymphatic Vessels ; Lymphedema ; Models, Animal ; Portal Vein ; Retrospective Studies ; Tomography, X-Ray Computed ; Vena Cava, Inferior

No abstract available.
Solitary Fibrous Tumors* ; Thoracic Cavity*

Adequate fluid management is an important therapeutic goal of dialysis. Recently, bioelectrical impedance methods have been used to determine body fluid status, but pediatric reports are rare. To determine the accuracy of bioelectrical impedance methods in the assessment of body fluid statusof children undergoing hemodialysis (HD), 12 children on HD were studied. A multi-frequency bioimpedance analysis device (Inbody S10) and bioimpedance spectroscopy device (BCM) were used to evaluate fluid status. Fluid removal during a HD session (assessed as body-weight change, ΔBWt) was compared with the difference in total body water determined by each device (measured fluid difference, ΔMF), which showed strong correlation using either method (Pearson's coefficient, r = 0.772 with Inbody S10 vs. 0.799 with BCM). Bioimpedance measurement indicated fluid overload (FO; ΔHS greater than 7%) in 34.8% with Inbody S10 and 56.5% with BCM, and only about 60% of children with FO by bioimpedance methods showed clinical symptoms such as hypertension and edema. In some patients with larger weight gain Inbody S10-assessed overhydration (OH) was much smaller than BCM-assessed OH, suggesting that BCM is more relevant in estimating fluid accumulation amount than Inbody S10. To our knowledge, this is the first report on the use of body composition monitors to assess fluid status in Korean children receiving HD.
Body Composition ; Body Fluids ; Body Water ; Child ; Dialysis ; Edema ; Electric Impedance ; Humans ; Hypertension ; Methods* ; Renal Dialysis* ; Spectrum Analysis ; Weight Gain