BACKGROUND: Endotoxin is a complex lipopolysaccharide molecule situated within the outer membrane of Gram-negative bacteria. Sepsis and acute respiratory failure (ARDS) can be induced by endotoxin. In order to introduce and develop the experimental model of ARDS in sepsis, we induced sepsis with the endotoxin and investigated the change of respiratory pathophysiology during sepsis using a multiple inert gas elimination technique (MIGET). METHODS: Ten New Zealand white rabbits were anesthetized and ventilated with a Harvard apparatus. In 5 rabbits, 2 mg/kg of lipopolysaccaride from E. coli was infused intravenously for 30 min (Toxin group). At 1, 2, 3, and 4 hours after endotoxin infusion, arterial blood gas, and hemodynamic profiles were checked. To perform the MIGET, six inert gases (SF6, krypton, desflurane, enflurane, diethyl ether, acetone) of widely varying solubility were infused peripherally and the excretion and retention data was determined from measurements of inert gas tensions in pulmonary arterial, systemic arterial blood samples and mixd expiratory gas sampling of pre and post septicemia using gas chromatography. We transformed and analysed the data into a V/Q distribution curve to find out the change of V/Q distribution curve. After the experiments, the animals were dissected and the lungs were extracted for wet/dry weight ratio (WW/DW) and microscopic examination. RESULTS: In the Toxin group, the pulmonary arterial pressures were increased and arterial oxygen tensions were decreased after the endotoxin infusion. The lung WW/DW were increased and inflammatory findings were seen in microscopic examination. In the MIGET, shunt, deadspace and log SDQ were increased in the toxin group, though there were wide V/Q distributions in the control group. CONCLUSIONS: We developed a successful endotoxin induced septic animal model, V/Q distribution curve and data using MIGET. The accomplishment of the experiment will not only allow us to better understand pulmonary pathophysiology of endotoxin induced sepsis using MIGET, but it will also contribute to other pulmonary physiology experiments associated with sepsis.
Animals ; Arterial Pressure ; Chromatography, Gas ; Enflurane ; Ether ; Gram-Negative Bacteria ; Hemodynamics ; Krypton ; Lung ; Membranes ; Models, Animal ; Models, Theoretical ; Noble Gases ; Oxygen ; Physiology ; Rabbits ; Respiratory Insufficiency ; Sepsis ; Solubility ; Ventilation-Perfusion Ratio*

PURPOSE: Rodent models that mimic human renal diseases are being increasingly recognized as powerful tools in the development of new drugs and for evaluating the efficacy of novel therapeutics in a preclinical setting. However, there are few reports on microvasculature imaging of the urinary system in small animals. An experimental study was performed to evaluate the microvasculature in a rat kidney using micro- computed tomography(CT) with three-dimensional images. MATERIALS AND METHODS: Five Sprague-Dawley male rats(age: 10-12 weeks, weight: 200-250g) underwent a laparotomy under anesthesia with an intramuscular injection of 0.5cc xylazine hydrochloride and ketamine mixed solution(1:10). After ligation of the abdominal aorta and inferior vena cava immediately above the renal artery, a 24 gazed catheter was inserted into the abdominal aorta. A physiological solution and heparin(500U) were infused through the catheter to flush the blood from the renal vasculature. The kidney was enhanced using self-made contrast material. The excised kidney was frozen for the micro-CT scan. RESULTS: The mean longitudinal diameter and weight of the 10 resected kidneys was 1.95+/-0.15cm and 2.0+/-0.28g, respectively. The images were represented by three-dimensional arrays of cubic voxels with opacities in the blood vessels. In the section taken from the arrays, four regions of the kidney could be identified easily by their characteristic vascular features. CONCLUSIONS: Micro-CT is a promising method for evaluating the renal microvascular architecture in a rat kidney. It can for the foundation of an experimental study aimed at providing quantitative information on the urinary system in a rodent model.
Anesthesia ; Animals ; Aorta, Abdominal ; Blood Vessels ; Catheters ; Humans ; Hydrazines ; Imaging, Three-Dimensional ; Injections, Intramuscular ; Ketamine ; Kidney ; Laparotomy ; Ligation ; Male ; Microcirculation ; Microvessels ; Rats ; Renal Artery ; Rodentia ; Vena Cava, Inferior ; Xylazine

OBJECTIVE: This study was to determine whether aquaporin-4, which plays role as a transcellular water channel, is expressed in human placenta, and to compare the degree of its expression between preeclamptic women and normal pregnant women. METHODS: Placentas were obtained from severely preeclamptic women and normal pregnant women who were delivered neonates by cesarean section before the onset of labor in the Chungbuk National University Hospital. Immunohistochemistry with aquaporin-4 antibody was performed using paraffin-embedded tissue section. Signal of aquaporin-4 expression was observed with light microscope. RESULTS: Immunohistochemistry demonstrated expression of aquaporin-4 in the placentas of both preeclamptic women and normal pregnant women. The degree of expression was not different in both group. CONCLUSION: Aquaporin-4 was expressed in the human placenta, but may not be related to the pathogenesis of preeclampsia.
Cesarean Section ; Chungcheongbuk-do ; Female ; Humans ; Immunohistochemistry ; Infant, Newborn ; Placenta* ; Pre-Eclampsia* ; Pregnancy ; Pregnant Women

PURPOSE: To determine the effect of photodynamic therapy (PDT) on patients with chronic central serous chorioretinopahty (CSC). METHODS: This was a retrospective multicenter study. We collected demographic and ophthalmic data for patients with chronic CSC who were treated with PDT from 16 institutions in Korea. The best corrected visual acuity (BCVA), ophthalmoscopic finding and optical coherence tomography at baseline and follow-up visits were compared longitudinally. RESULTS: Sixty-five eyes of 65 patients were recruited. Males (51 patients, 78.5%) outnumbered females (14 patients, 21.5%). The mean age was 46.4+/-10.0 years of age (28~69). By 1 month, mean BCVA improved from 0.47 to 0.37 (logarithm of the minimum angle of resolution) (P <0.01). This BCVA increased throughout 6 months. Subretinal fluid resolved partially or completely in 89.1% of the patients. Central macular thickness (CMT) decreased from 303.4 to 168.7 micrometer. The amount of change in CMT after PDT was correlated to the female sex and prePDT CMT. At 3 months after PDT, the amount of change in BCVA was significantly related to that of change of CMT (p <0.05). Adverse events were reported in 4 cases, however, most were mild. CONCLUSIONS: PDT was effective and safe for treating chronic CSC.
Eye ; Female ; Follow-Up Studies ; Humans ; Korea ; Male ; Photochemotherapy ; Retrospective Studies ; Subretinal Fluid ; Tomography, Optical Coherence ; Triazenes ; Visual Acuity

PURPOSE: To evaluate the efficacy of photodynamic therapy (PDT) with verteporfin for polypoidal choroidal vasculopathy (PCV) in Korean patients. METHODS: Clinical data of patients who were treated with PDT for PCV and followed up for more than 6 months were collected from 14 hospitals around the country. The changes in the best corrected visual acuity, angiographic outcome, retinal thickness measured by optical coherence tomography (OCT), and adverse effects of treatment were evaluated. RESULTS: Eighty six patients (86 eyes) were recruited (male: 75.6%, age: 65.9+/-8.3 years, mean follow-up: 14.8+/-10.2 months). The mean logMAR visual acuity at baseline was 0.55+/-0.32 and did not show any statistically significant difference from the final mean logMAR visual acuity (0.53+/-0.54) (p=0.639). The mean treatment session number of PDT was 2+/-1.2. Visual acuity stabilized or improved in 70.9% of patients. Visual acuity improved by more than 2 lines in 33 eyes (38.4%) and worsened by more than 2 lines in 21 eyes (24.4%) of patients. Vascular leakage decreased in 62.5% of patients in fluorescein angiography and polypoidal lesions disappeared or were reduced in 57.3% of patients in indocyanine green angiography. There was no systemic adverse effect of PDT, but increased subretinal hemorrhage after PDT occurred in 10 eyes (11.6%). CONCLUSIONS: In polypoidal choroidal vasculopathy, photodynamic therapy with verteporfin is safe and effective for preserving visual acuity and reducing vascular leakage and retinal thickness.
Angiography ; Choroid ; Eye ; Fluorescein Angiography ; Hemorrhage ; Humans ; Indocyanine Green ; Photochemotherapy ; Porphyrins ; Retinaldehyde ; Retrospective Studies ; Tomography, Optical Coherence ; Triazenes ; Visual Acuity

PURPOSE: To investigate the effects of repeated photodynamic therapy (PDT) for subfoveal choroidal neovascularization secondary to age-related macular degeneration (AMD) in Korean patients. METHODS: Clinical data of patients who were treated with repeated (3 times or more) PDT for subfoveal choroidal neovascularization secondary to AMD and followed up for more than 6 months were collected from 17 hospitals around the country. Visual outcomes at 12 and 24 months, follow-up were compared between subtypes of choroidal neovascularization. The factors related to final visual prognosis and PDT-related adverse effects were evaluated. RESULTS: 244 patients (244 eyes) were recruited (male: 60%, age: 67.7+/-9.1 years). The portion of patients with predominantly classic, minimally classic, and occult without classic choroidal neovascularization was 57%, 13%, and 24%, respectively and that of patients with visual improvements or less than moderate visual loss at 24 months follow-up were 28%, 38%, 30% and 47%, 56%, and 65%, respectively. Baseline visual acuity and age were significantly related to the final visual prognosis (p<0.05). PDT-related adverse events developed in 15 (6.1%) patients, but most were mild and transient. CONCLUSIONS: Repeated PDT for subfoveal choroidal neovascularization secondary to AMD has effects comparable to those of previous prospective, controlled trials without any significant safety concerns in Korea.
Choroid* ; Choroidal Neovascularization* ; Follow-Up Studies ; Humans ; Korea ; Macular Degeneration* ; Photochemotherapy* ; Prognosis ; Visual Acuity