Assessment of acute inhalation toxicity of citric acid and sodium hypochlorite in rats

Background@#Citric acid (CA) and sodium hypochlorite (NaOCl) have been used to disinfect animals to protect them against avian influenza and foot-and-mouth disease. @*Objectives@#We performed a good laboratory practice (GLP)-compliant animal toxicity study to assess the acute toxic effects of CA and NaOCl aerosol exposure in Sprague-Dawley rats. @*Methods@#Groups of five rats per sex were exposed for 4 h to four concentrations of the two chemicals, i.e., 0.00, 0.22, 0.67, and 2.00 mg/L, using a nose-only exposure. After a single exposure to the chemicals, clinical signs, body weight, and mortality was observed during the observation period. On day 15, an autopsy, and then gross findings, and histopathological analysis were performed. @*Results@#After exposure to CA and NaOCl, body weight loss was observed but recovered.Two males died in the CA 2.00 mg/L group and, two males and one female died in the 2.00 mg/L NaOCl group. In the gross findings and histopathological analysis, discoloration of the lungs was observed in the CA exposed group and inflammatory lesions with discoloration of the lungs were observed in the NaOCl exposed group. These results suggest that the lethal concentration 50 (LC50) of CA is 1.73390 mg/L for males and > 1.70 mg/L for females. For NaOCl, the LC50 was 2.22222 mg/L for males and 2.39456 mg/L for females. @*Conclusions@#The Globally Harmonized System is category 4 for both CA and NaOCl. In this study, the LC50 results were obtained through a GLP-based acute inhalation toxicity assessment. These results provide useful data to reset safety standards for CA and NaOCl use.

Surgical removal of a telemetry system in a cynomolgus monkey (Macaca fascicularis):a 12-month observation study / 한국실험동물학회지

Background@#Telemetry is a wireless implanted device that measures biological signals in conscious animals and usually requires surgery for its removal when the study is finished. After removing the device, the animals are either used for other studies or euthanatized.Case presentation: Herein, we report the case of a living cynomolgus monkey (Macaca fascicularis) that was used for the entire experimental period, instead of euthanasia, after surgical removal of an implanted telemetry system.Radiography was used to determine the status of the implanted telemetry, following which, a repair surgery was performed for removing the system; clinical signs were used to preserve the life of the cynomolgus monkey. Postoperative clinical signs, food consumption, hematology, and serum biochemistry were examined during the 12-month observational period. No abnormal readings or conditions were observed in the subject after implant removal. @*Conclusions@#This study may be a useful case report for living cynomolgus monkeys in telemetry implantations used throughout the study period. We suggest minimizing the suffering and improving the welfare of these animals.

Higher incidence of sperm granuloma in the epididymis of C57BL/6N mice / 한국실험동물학회지

C57BL/6N mice are inbred strains widely used in biomedical research. Hence, a large amount of basic data has been accumulated. However, in the field of histopathology, spontaneous data for relatively younger mice that are used more frequently are not yet abundant, in contrast to data for older mice and their neoplastic lesions. To acquire the essential background data required by various research and toxicological assessments, 120 mice of the C57BL/6N strain (10 and 13 weeks of age) were collected from two institutions (From Korea and Japan) and subjected to histopathological analyses of the major organs (liver, spleen, kidney, thymus, heart, testis, epididymis). The results showed significantly higher incidence of sperm granulomas in the epididymides (10-56%) of these mice, compared with that in other strains or species of lab animals. Upon closer inspection, oligospermia/clear cell hyperplasia, cellular debris, and tubular vacuolation were also observed in the epididymides with sperm granulomas. Moreover, diseased organs were significantly heavier than healthy ones. Immunohistochemical staining showed a significant increase in the chromatic figures of cysteine-dependent aspartate-directed proteases-3 (caspase-3) and cleaved-poly(ADP-ribose) polymerase (c-PARP), and damages to the tubule due to spontaneous apoptosis, which may have led to the sperms leaking out of the tubule, causing the granuloma. To conclude, spontaneous sperm granuloma can occur in 10- and 13-week-old C57BL/6N mice and may thus affect the results of various studies using these mice. Therefore, sperm granuloma in epididymis needs to be carefully considered as an important factor when design the study using C57BL/6N.

Reference values of clinical pathology parameters in cynomolgus monkeys (Macaca fascicularis) used in preclinical studies / 한국실험동물학회지

Nonhuman primates are increasingly used in biomedical research since they are highly homologous to humans compared to other rodent animals. However, there is limited reliable reference data of the clinical pathology parameters in cynomolgus monkeys, and in particular, only some coagulation and urinalysis parameters have been reported. Here, we reported the reference data of clinical chemical, hematological, blood coagulation, and urinalysis parameters in cynomolgus monkeys. The role of sex differences was analyzed and several parameters (including hematocrit, hemoglobin, red blood cell, blood urea nitrogen, total bilirubin, alkaline phosphatase, creatinine kinase, gamma-glutamyl tranferase, and lactate dehydrogenase) significantly differed between male and female subjects. In addition, compared to previous study results, lactate dehydrogenase, creatinine kinase, and aspartate aminotransferase showed significant variation. Interstudy differences could be affected by several factors, including age, sex, geographic origin, presence/absence of anesthetics, fasting state, and the analytical methods used. Therefore, it is important to deliberate with the overall reference indices. In conclusion, the current study provides a comprehensive and updated reference data of the clinical pathology parameters in cynomolgus monkeys and provides improved assessment criteria for evaluating preclinical studies or biomedical research.

Complicated Acute Aortic Dissection with Malperfusion of the Left Common Iliac Artery Treated with Thoracic Endovascular Aortic Repair / 대한내과학회지

Acute aortic dissection with malperfusion syndrome is associated with poor clinical outcomes, and surgical treatment for complicated descending aortic dissections is associated with a high risk of operative mortality. Endovascular repair is emerging as a good alternative to surgery. Endovascular repair for a descending aortic dissection with malperfusion syndrome offers good clinical outcomes because of technical and anatomical benefits. Here, we report a case of descending aortic dissection and malperfusion syndrome in the left common iliac artery that was successfully treated with an aortic stent graft and peripheral stent.

Acute Upper Limb Ischemia Suspected to Have Originated from Staphylococcus Epidermidis Native Valve Endocarditis / 대한내과학회지

We report a case of acute upper limb ischemia suspected to have originated from methicillin-resistant Staphylococcus epidermidis native valve endocarditis in a 57-year-old man who had complained of sudden-onset fever and pain in the right hand. 3D computed tomography of the right upper extremity detected a thrombus occluding the brachial artery. Echocardiography showed a large vegetation on the aortic valve. Thus, we suspected, clinically, brachial artery occlusion by septic emboli originating from a large vegetation of the aortic valve. The patient was treated with intravenous antibiotics for the suspected methicillin-resistant Staphylococcus epidermidis-native valve endocarditis with a combination of percutaneous aspiration thromboembolectomy and selective intra-arterial thrombolysis for acute thromboembolic occlusion in the right upper limb. The large vegetation of the aortic valve resolved without surgery and aortic regurgitation improved. The patient recovered uneventfully with no complications, including septic embolism, over the following 11 months.

Negative Pressure Pulmonary Edema Together with Pneumopericardium after General Anesthesia / 대한내과학회지

Negative pressure pulmonary edema is an uncommon complication related to general anesthesia. Its main pathophysiology is excessive negative intrathoracic pressure that is caused by an acute upper airway obstruction. Pneumopericardium, the presence of air within the pericardial sac, is another rare condition. The common pathophysiology of pneumopericardium, except for that caused by blunt or penetrating trauma, is barotrauma-induced alveolar rupture caused by positive intrathoracic pressure. Here, we report the case of a 61-year old female patient with negative pulmonary edema and pneumopericardium after general anesthesia. She recovered after conservative management.

The Relationship between Microcirculatory Resistance and Fractional Flow Reserve in Patients with Acute Myocardial Infarction

BACKGROUND AND OBJECTIVES: It was demonstrated that the fractional flow reserve (FFR) with partial balloon obstruction may have implications for assessing viable myocardium. In a different way, the index of microcirculatory resistance (IMR) was introduced as a useful indicator for assessing microvascular function. We evaluated the relationship between the FFR0.8 and the IMR. SUBJECTS AND METHODS: We studied 48 consecutive patients who had undergone coronary intervention for acute myocardial infarction (AMI). After revascularization using stent(s), an undersized short balloon was positioned inside the stent and inflated to create a specific normalized pressure drop of FFR (distal coronary/aortic pressure=0.80) at rest. The FFR0.8 was obtained during hyperemia with the fixed state balloon-induced partial obstruction. IMR was measured by three injections of saline. The association between the FFR0.8 and the IMR was investigated. RESULTS: The mean age of the patients was 60+/-12 years and 36 (75%) overall presented with ST-segment elevation myocardial infarction. The mean FFR0.8 was 0.68+/-0.06. A statistically significant correlation between the FFR0.8 and the log-transformed IMR(true) (LnIMR(true)) was found through a multivariable linear regression analysis (beta=0.056, p<0.001). Both the FFR0.8 and the LnIMR(true) had a positive correlation with the log-transformed peak troponin I (TnI) with statistical significance (r2=0.119, p=0.017; r2=0.225, p=0.006, respectively). CONCLUSION: There was a positive correlation between the LnIMR(true) and the FFR0.8. Both of the values were associated with peak TnI. Those values may be used as appropriate surrogate measures of microvascular function after AMI.

Effects of Low Dose Pioglitazone on Restenosis and Coronary Atherosclerosis in Diabetic Patients Undergoing Drug Eluting Stent Implantation

PURPOSE: Thiazolidinediones are insulin-sensitizing agents that reduce neointimal proliferation and the adverse clinical outcomes associated with percutaneous coronary intervention (PCI) in patients with diabetes mellitus (DM). There is little data on whether or not low dose pioglitazone reduces adverse clinical outcomes. MATERIALS AND METHODS: The study population included 121 DM patients with coronary artery disease and they were randomly assigned to 60 patients taking 15 mg of pioglitazone daily in addition to their diabetic medications and 61 patients with placebo after the index procedure with drug-eluting stents (DESs). The primary end points were rate of in-stent restenosis (ISR) and change in atheroma volume and in-stent neointimal volume. The secondary end points were all-cause death, myocardial infarction (MI), stent thrombosis and re-PCI. RESULTS: There were no statistical differences in the clinical outcomes and the rate of ISR between the two groups [all-cause death; n=0 (0%) in the pioglitazone group vs. n=1 (1.6%) in the control group, p=0.504, MI; n=2 (3.3%) vs. n=1 (1.6%), p=0.465, re-PCI; n=6 (10.0%) vs. n=6 (9.8%), p=0.652, ISR; n=4 (9.3%) vs. n=4 (7.5%), p=1.000, respectively]. There were no differences in changes in neointimal volume, percent neointimal volume, total plaque volume and percent plaque volume between the two groups on intravascular ultrasonography (IVUS) study. CONCLUSION: Our study demonstrated that low dose pioglitazone does not reduce rate of ISR, neointimal volume nor atheroma volume in DM patients who have undergone PCI with DESs, despite the limitations of the study.

A case of accessory splenic tuberculosis mimicking a distal pancreatic tumor / 대한내과학회지

Abdominal tuberculosis usually affects the gastrointestinal tract, peritoneum, lymph nodes, liver or spleen. Tuberculosis of the spleen is uncommon, except when associated with miliary dissemination. We report a case of a 33-year-old man with tuberculosis of the accessory spleen, which was originally suspected to be a distal pancreatic tumor. He was admitted with a history of left upper quadrant abdominal pain for 3 months. Computed tomography imaging of the abdomen revealed a 4.5 cm sized poorly defined hypodense mass in the distal pancreas and showed multiple focal hypodense lesions in the enlarged spleen. We performed distal pancreatectomy and splenectomy under the preoperative expectation of a distal pancreatic tumor. Microscopic examination of the specimens revealed accessory splenic tuberculosis associated with splenic tuberculosis. Following this, he was treated with appropriate antituberculosis drugs and was discharged without any complications.

A Case of Reactive Arthritis in a Patient with Clostridium Difficile Diarrhea / 대한류마티스학회지

Clostridium difficile is the leading cause of hospital-acquired diarrhea. The frequent use of antibiotics and chemotherapeutic agents increases the likelihood of acquiring Clostridium difficile-associated disease. Reactive arthritis is a recognized sequela of infection with a many types of enteric or urogenital pathogens. Although the main bacterial causes of reactive arthritis following enteric infection are Salmonella, Shigella, Campylobacter and Yersinia, Clostridium difficile should be considered as a rare cause of reactive arthritis. We report here on a case of a 63-year-old man who presented with reactive arthritis following an infection with Clostridium difficile.

A case of multiple hepatic adenomas and gout with glycogen storage disease type Ia / 대한내과학회지

Glycogen storage disease (GSD) type Ia is a rare inherited metabolic disease characterized by glucose-6-phosphatase (G6Pase) deficiency, which results in many metabolic problems, such as fasting hypoglycemia, lactic acidosis, hyperuricemia, and hyperlipidemia. The metabolic derangements may result in long-term complications, including growth retardation, gout, hepatic adenomas, and renal disease. A 26-year-old male was admitted with general weakness, multiple subcutaneous mass-like lesions, and hepatomegaly. He was diagnosed as GSD type Ia through analysis of the G6Pase gene. This disease is found mainly in childhood, but we diagnosed a case of GSD type Ia during a work-up of arthralgia and hepatomegaly in an adult patient. We report this case with a review of the literature

A case of acro-osteolysis caused by peripheral neuropathy after minor burn injury / 대한내과학회지

Acro-osteolysis is characterized by bone resorption in the fingers and toes and can occur in several diseases. Occupational exposure to polyvinyl chloride polymers, thermal injury, and repetitive mechanical injury can also cause acro-osteolysis. The pathophysiology of the disease is unknown, but a unifying theme of vascular and mechanical injury is presented. Signs include Raynaud's phenomenon, bone loss in the hand and cold sensitivity. We report the case of a 67-year-old woman who presented with acro-osteolysis after being burned repeatedly.

A case of acro-osteolysis caused by peripheral neuropathy after minor burn injury / 대한내과학회지

Acro-osteolysis is characterized by bone resorption in the fingers and toes and can occur in several diseases. Occupational exposure to polyvinyl chloride polymers, thermal injury, and repetitive mechanical injury can also cause acro-osteolysis. The pathophysiology of the disease is unknown, but a unifying theme of vascular and mechanical injury is presented. Signs include Raynaud's phenomenon, bone loss in the hand and cold sensitivity. We report the case of a 67-year-old woman who presented with acro-osteolysis after being burned repeatedly.