Animal models are useful tools to study the molecular basis of schizophrenia pathophysiology and efficacy of potential therapeutic agents. Schizophrenia animal models can be subdivided into three classes ; drug-induced models, genetic models, and environmental models and each model is designed based on specific traits corresponding to the characteristic symptoms of human schizophrenia patients. Psychomotor agitation and sensitivity to psychotomimetic drugs are often thought to reflect positive symptoms. Social interaction deficits and affective impairments are known to correspond to negative symptoms. Also, cognitive symptoms have been linked to the working memory impairments, attention deficits and related cognitive deficits in animals. To analyze such components in quantifiable manners, various behavioral paradigms have been developed and utilized. Here, we overview these animal models, focusing on underlying rationales for their use in the context of schizophrenia research.
Animals ; Behavior, Animal ; Humans ; Interpersonal Relations ; Memory, Short-Term ; Models, Animal* ; Models, Genetic ; Neurobehavioral Manifestations ; Psychomotor Agitation ; Schizophrenia*

BACKGROUND: The results of the National Institute of Neurological Disorders and Stroke (NINDS) r-tPA Stroke Trial generated considerable hope, but also concerns about whether their results could be replicated in clinical practice. We investigated whether r-tPA infusion could be administered in a community-based hospital, safely and effectively. METHODS: We analyzed, retrospectively, the data of 33 patients having suffered acute ischemic strokes and treated with intravenous r-tPA from February 2003 to December 2006. Safety was evaluated by intracranial hemorrhage, symptomatic intracranial hemorrhage, and mortality. Clinical neurological status was measured by National Institutes of Health Stroke Scale (NIHSS) at baseline, 24 hours, and 7 days after r-tPA treatment. Efficacy was assessed by the response rate of r-tPA using an improvement in the NIHSS by 4 or more points at 24 hours after treatment and the long-term out-come measured with the modified Rankin Scale (mRS) at 3 months after stroke. RESULTS: The median NIHSS was 18. Mean onset to needle time was 140+/-30 minutes. Of the 33 patients, 10 had intracranial hemorrhage and 2 had symptomatic intracranial hemorrhage. No deaths occurred. Fifteen patients showed improvement in their NIHSS by 4 or more points at 24 hours after r-tPA. On the mRS, 12 patients had a good outcome at 3 months. More specifically, 9 patients had no or minimal symptoms, 7 patients had mild to moderate disability, 10 patients had severe disability and 7 patients died. CONCLUSION: The safety andrd efficacy of administering intravenous r-tPA for acute ischemic stroke in a community-based hospital mirror the results of the NINDS stroke trial.
Humans ; Intracranial Hemorrhages ; National Institute of Neurological Disorders and Stroke ; National Institutes of Health (U.S.) ; Needles ; Retrospective Studies ; Stroke ; Tissue Plasminogen Activator

BACKGROUND: The results of the National Institute of Neurological Disorders and Stroke (NINDS) r-tPA Stroke Trial generated considerable hope, but also concerns about whether their results could be replicated in clinical practice. We investigated whether r-tPA infusion could be administered in a community-based hospital, safely and effectively. METHODS: We analyzed, retrospectively, the data of 33 patients having suffered acute ischemic strokes and treated with intravenous r-tPA from February 2003 to December 2006. Safety was evaluated by intracranial hemorrhage, symptomatic intracranial hemorrhage, and mortality. Clinical neurological status was measured by National Institutes of Health Stroke Scale (NIHSS) at baseline, 24 hours, and 7 days after r-tPA treatment. Efficacy was assessed by the response rate of r-tPA using an improvement in the NIHSS by 4 or more points at 24 hours after treatment and the long-term out-come measured with the modified Rankin Scale (mRS) at 3 months after stroke. RESULTS: The median NIHSS was 18. Mean onset to needle time was 140+/-30 minutes. Of the 33 patients, 10 had intracranial hemorrhage and 2 had symptomatic intracranial hemorrhage. No deaths occurred. Fifteen patients showed improvement in their NIHSS by 4 or more points at 24 hours after r-tPA. On the mRS, 12 patients had a good outcome at 3 months. More specifically, 9 patients had no or minimal symptoms, 7 patients had mild to moderate disability, 10 patients had severe disability and 7 patients died. CONCLUSION: The safety andrd efficacy of administering intravenous r-tPA for acute ischemic stroke in a community-based hospital mirror the results of the NINDS stroke trial.
Humans ; Intracranial Hemorrhages ; National Institute of Neurological Disorders and Stroke ; National Institutes of Health (U.S.) ; Needles ; Retrospective Studies ; Stroke ; Tissue Plasminogen Activator

OBJECTIVES: To elucidate the transient effects on the risk of occupational injuries as acute events and establish an alternative proposal. METHODS: The study population comprised a total of 302 workers randomly selected from applications for occupational injury compensation reported to the Inchon local labor office from January 1, 1999 to December 31. A case-crossover design, where each case serves its own control, was applied to this study. Through a telephone interview, workers provided useful data concerning five job related stressful events such as company transfer, work load change, overtime work, exchange duty, and work-part transfer. They were asked whether there were stressful events within a week of the occurrence of injury and the degree of stress. Exposure status from one year prior was used as control information. In the end, the data provided by 158 of selected persons was used for the analysis based on the quality of the data provided by the participants. A conditional logistic regression was used to discover the transient effects on the risk of occupational injuries as acute events. RESULTS: The effect of a company transfer and work load change on occupational injury was statistically significant on the risk of occupational injuries as an acute event(RR=5.5, 95% CI=2.501-12.428; RR=3.1, 95% CI=1.963-5.017, respectively). Other stressful events were found to elevate the risk factor for the occurrence of occupational injury, but were not significant. CONCLUSIONS: Our results suggested that transient stressful events elevated the risk factor for the occurrence of occupational injury.
Compensation and Redress ; Humans ; Incheon ; Interviews as Topic ; Life Change Events ; Logistic Models ; Occupational Injuries* ; Risk Factors

PURPOSE: Verrucous carcinoma is a rare, low-grade and well-differentiated squamous cell carcinoma, representing as a warty tumor. Estimation of the incidence for cutaneous lesions is not available because they are rare. We describe a case of verrucous carcinoma, a rare type, complication of a chronic pressure ulcer of duration more than 15 years. METHODS: A 17-year-old boy presented with a large lesion involving the sacral area, which had been neglected for about 15 years. He had a history of surgical extirpation 2 years ago, but not cured. Examination revealed a cauliflower-like mass arising from an irregularly oval-shaped tumor which was 6.0x4.5cm in size with signs of infection and ulcer. The lesion involved the sacrococcygeal area, spreading to both medial gluteal regions. The perianal skin did not appear to be directly affected. RESULTS: A preoperative punch biopsy revealed a extremely well differentiated verrucous carcinoma. There were positive results in immunohistochemistry in the items of p53, p63, Ki-67. An 'en-bloc' excision of the tumor with the clinically normal surrounding tissue was carried out. Reconstruction was achieved by local regional flap. Histopathological findings of the excised area fully confirmed the preoperative biopsy report. It remained free of recurrence for a period of about 8 months. CONCLUSION: We believe that in patients with buttock involvement, regardless of the extent of such tumors, surgical therapy should be considered as the first-choice of treatment as reconstruction can be performed without excessive impairment for the patient.
Adolescent ; Biopsy ; Buttocks ; Carcinoma, Squamous Cell ; Carcinoma, Verrucous* ; Humans ; Immunohistochemistry ; Incidence ; Male ; Pressure Ulcer* ; Recurrence ; Skin ; Ulcer

BACKGROUND: Polydeoxyribonucleotide (PDRN) is known to have anti-inflammatory and angiogenic effects and to accelerate wound healing. The aim of this study was to investigate whether PDRN could improve peripheral tissue oxygenation and angiogenesis in diabetic foot ulcers. METHODS: This was a prospective randomized controlled clinical trial. Twenty patients with a non-healing diabetic foot ulcer were randomly distributed into a control group (n=10) and a PDRN group (n=10). Initial surgical debridement and secondary surgical procedures such as a split-thickness skin graft, primary closure, or local flap were performed. Between the initial surgical debridement and secondary surgical procedures, 0.9% normal saline (3 mL) or PDRN was injected for 2 weeks by the intramuscular (1 ampule, 3 mL, 5.625 mg, 5 days per week) and perilesional routes (1 ampule, 3 mL, 5.625 mg, 2 days per week). Transcutaneous oxygen tension (TcPO2) was evaluated using the Periflux System 5000 with TcPO2/CO2 unit 5040 before the injections and on days 1, 3, 7, 14, and 28 after the start of the injections. A pathologic review (hematoxylin and eosin stain) of the debrided specimens was conducted by a pathologist, and vessel density (average number of vessels per visual field) was calculated. RESULTS: Compared with the control group, the PDRN-treated group showed improvements in peripheral tissue oxygenation on day 7 (P < 0.01), day 14 (P < 0.001), and day 28 (P < 0.001). The pathologic review of the specimens from the PDRN group showed increased angiogenesis and improved inflammation compared with the control group. No statistically significant difference was found between the control group and the PDRN group in terms of vessel density (P=0.094). Complete healing was achieved in every patient. CONCLUSIONS: In this study, PDRN improved peripheral tissue oxygenation. Moreover, PDRN is thought to be effective in improving inflammation and angiogenesis in diabetic foot ulcers.
Angiogenesis Modulating Agents ; Blood Gas Monitoring, Transcutaneous ; Debridement ; Diabetic Foot* ; Eosine Yellowish-(YS) ; Foot Ulcer ; Humans ; Inflammation ; Oxygen* ; Polydeoxyribonucleotides ; Prospective Studies ; Skin ; Transplants ; Ulcer* ; Wound Healing

BACKGROUND: Polydeoxyribonucleotide (PDRN) is known to have anti-inflammatory and angiogenic effects and to accelerate wound healing. The aim of this study was to investigate whether PDRN could improve peripheral tissue oxygenation and angiogenesis in diabetic foot ulcers. METHODS: This was a prospective randomized controlled clinical trial. Twenty patients with a non-healing diabetic foot ulcer were randomly distributed into a control group (n=10) and a PDRN group (n=10). Initial surgical debridement and secondary surgical procedures such as a split-thickness skin graft, primary closure, or local flap were performed. Between the initial surgical debridement and secondary surgical procedures, 0.9% normal saline (3 mL) or PDRN was injected for 2 weeks by the intramuscular (1 ampule, 3 mL, 5.625 mg, 5 days per week) and perilesional routes (1 ampule, 3 mL, 5.625 mg, 2 days per week). Transcutaneous oxygen tension (TcPO2) was evaluated using the Periflux System 5000 with TcPO2/CO2 unit 5040 before the injections and on days 1, 3, 7, 14, and 28 after the start of the injections. A pathologic review (hematoxylin and eosin stain) of the debrided specimens was conducted by a pathologist, and vessel density (average number of vessels per visual field) was calculated. RESULTS: Compared with the control group, the PDRN-treated group showed improvements in peripheral tissue oxygenation on day 7 (P < 0.01), day 14 (P < 0.001), and day 28 (P < 0.001). The pathologic review of the specimens from the PDRN group showed increased angiogenesis and improved inflammation compared with the control group. No statistically significant difference was found between the control group and the PDRN group in terms of vessel density (P=0.094). Complete healing was achieved in every patient. CONCLUSIONS: In this study, PDRN improved peripheral tissue oxygenation. Moreover, PDRN is thought to be effective in improving inflammation and angiogenesis in diabetic foot ulcers.
Angiogenesis Modulating Agents ; Blood Gas Monitoring, Transcutaneous ; Debridement ; Diabetic Foot* ; Eosine Yellowish-(YS) ; Foot Ulcer ; Humans ; Inflammation ; Oxygen* ; Polydeoxyribonucleotides ; Prospective Studies ; Skin ; Transplants ; Ulcer* ; Wound Healing

BACKGROUND: Iron and steel foundry workers are exposed to various toxic and carcinogenic substances including crystalline silica, polycyclic aromatic hydrocarbons, and arsenic. Studies have been conducted on lung cancer in iron and steel founding workers and the concentration of crystalline silica in foundries; however, the concentration of crystalline silica and cases of lung cancer in a single foundry has never been reported in Korea. Therefore, the authors report two cases of lung cancer and concentration of crystalline silica by the X-ray diffraction method. CASE PRESENTATION: A 55-year-old blasting and grinding worker who worked in a foundry for 33 years was diagnosed with lung cancer. Another 64-year-old forklift driver who worked in foundries for 39 years was also diagnosed with lung cancer. Shot blast operatives were exposed to the highest level of respirable quartz (0.412 mg/m3), and a forklift driver was exposed to 0.223 mg/m3. CONCLUSIONS: The lung cancer of the two workers is very likely due to occupationally related exposure given their occupational history, the level of exposure to crystalline silica, and epidemiologic evidence. Further studies on the concentration of crystalline silica in foundries and techniques to reduce the crystalline silica concentration are required.
Arsenic ; Crystallins ; Humans ; Iron ; Korea ; Lung Neoplasms* ; Lung* ; Middle Aged ; Occupational Exposure ; Occupations ; Polycyclic Hydrocarbons, Aromatic ; Quartz ; Silicon Dioxide ; Steel ; X-Ray Diffraction

PURPOSE: Multiple chemical sensitivity (MCS) is a clinical syndrome representing multi-organ and psychological symptoms caused by chronic exposure to various chemicals in low concentrations. We evaluated the prevalence and related factors of MCS targeting Korean adults using the Quick Environmental Exposure and Sensitivity Inventory (QEESI(c)). METHODS: A total of 446 participants were recruited from Severance Hospital. Participants underwent a questionnaire interview including questions on sociodemographic factors, occupational and environmental factors, allergic diseases, and the QEESI(c). Among them, 379 participants completed the questionnaire and the QEESI(c). According to the QEESI(c) interpretation results, participants were divided into very suggestive (VS) group and less suggestive (LS) group. RESULTS: The estimated prevalence of MCS was higher in allergic patients than non-allergic participants (19.7% and 11.3%, respectively, P=0.04). In the multivariate logistic regression analysis, ages of 30-39 (OR, 2.94; 95% CI, 1.25-6.95) and those of 40-49 (OR, 2.51; 95% CI, 1.02-6.21) were significantly related to MCS compared to those aged less than 30 years. Female sex (OR, 2.16; 95% CI, 1.11-4.18), experience of dwelling in a new house (OR, 2.05; 95% CI, 1.04-4.03), and atopic dermatitis (OR, 1.95; 95% CI, 1.04-3.69) were also significantly related to MCS. However, only age of 30-39 in the allergic group was significant in the stratified analysis. CONCLUSIONS: The estimated prevalence of MCS was higher among allergic patients than non-allergic participants. People with experience of dwelling in a new house and atopic dermatitis were more at risk of being intolerant to chemicals. Further studies to provide the nationally representative prevalence data and clarify risk factors and mechanisms of MCS are required.
Adult* ; Dermatitis, Atopic ; Environmental Exposure ; Female ; Humans ; Logistic Models ; Multiple Chemical Sensitivity* ; Prevalence ; Risk Factors

BACKGROUND: Many studies of the effect of catechins, a major substance in green tea, on sarcopenia have been conducted using animal models or as in vitro experiments, revealing that they increase muscle mass, inhibit proteases, and promote satellite cell proliferation. No study has been conducted targeting human subjects relative to the correlation between green tea and sarcopenia. The purpose of this study was to investigate the correlation between green tea intake and sarcopenia in menopausal women using the Korea National Health and Nutrition Examination Survey (2008–2011).METHODS: This study included 3,473 menopausal women after excluding those diagnosed with gastric cancer and other cancers. The frequency of green tea intake was determined based on the Food Frequency Questionnaire, and the value acquired from calibrating the extremity muscle mass measured using dual-energy X-ray absorptiometry with weight was used as the muscle mass. Sarcopenia was defined using values less than two standard deviations as cut-offs after determining the mean and standard deviation of the muscle mass in the group of young and healthy women.RESULTS: In menopausal women, the odds ratio of the group drinking a cup or less and two or more cups of green tea to that of the group not drinking green tea was 1.170 (0.891–1.536), and the 95% confidence interval was 1.530 (0.744–3.146). A significant linear trend was not observed in the result (P for trend 0.148).CONCLUSION: There was no significant correlation between green tea intake and sarcopenia in menopausal women in Korea.
Absorptiometry, Photon ; Catechin ; Cell Proliferation ; Cross-Sectional Studies ; Drinking ; Extremities ; Female ; Humans ; In Vitro Techniques ; Korea ; Models, Animal ; Nutrition Surveys ; Odds Ratio ; Peptide Hydrolases ; Sarcopenia ; Stomach Neoplasms ; Tea