74 research outputs found
Opisthorchiasis-associated biliary stones: light and scanning electron microscopic study
Aim: Biliary stones are frequently encountered in areas endemic for opisthorchiasis in Thailand. The present study was to describe the prevalence and pathogenesis of these stones. Methods: Gallstones and/or common bile duct stones and bile specimens from 113 consecutive cholecystectomies were included. Bile samples, including sludge and/or microcalculi, were examined for Opisthorchis viverrini eggs, calcium and bilirubin. The stones were also processed for scanning electron microscopic (SEM) study. Results: Of the 113 cases, 82 had pigment stones, while one had cholesterol stones. The other 30 cases had no stones. Most of the stone cases (76%, 63/83) had multiple stones, while the remainder had a single stone. Stones were more frequently observed in females. Bile examination was positive for O. viverrini eggs in 50% of the cases studied. Aggregates of calcium bilirubinate precipitates were observed in all cases with sludge. Deposition of calcium bilirubinate on the eggshell was visualized by special staining. A SEM study demonstrated the presence of the parasite eggs in the stones. Numerous crystals, morphologically consistent with calcium derivatives and cholesterol precipitates, were seen. Conclusion: Northeast Thailand has a high prevalence of pigment stones, as observed at the cholecystectomy, and liver fluke infestation seems involved in the pathogenesis of stone formation. Copyrigh
Human Angiostrongyliasis Outbreak in Dali, China
Angiostrongyliasis, caused by the rat lungworm Angiostrongylus cantonensis, is a potentially fatal food-borne disease. It is endemic in parts of Southeast Asia, the Pacific Islands, Australia, and the Caribbean. Outbreaks have become increasingly common in China due to the spread of efficient intermediate host snails, most notably Pomacea canaliculata. However, infections are difficult to detect since the disease has a rather long incubation period and few diagnostic clinical symptoms. Reliable diagnostic tests are not widely available. The described angiostrongyliasis epidemic in Dali, China lasted for eight months. Only 11 of a total of 33 suspected patients were clinically confirmed based on a set of diagnostic criteria. Our results demonstrate that the rapid and correct diagnosis of the index patient is crucial to adequately respond to an epidemic, and a set of standardized diagnostic procedures is needed to guide clinicians. Integrated control and management measures including health education, clinical guidelines and a hospital-based surveillance system, should be implemented in areas where snails are a popular food item
Subretinal angiostrongyliasis-induced optic neuritis
Suthasinee Sinawat,1 Yosanan Yospaiboon,1 Supat Sinawat21Vitreoretinal Unit, Department of Ophthalmology, 2Department of Physiology, Khon Kaen University, Khon Kaen, ThailandAbstract: A 27-year-old Thai male presented with progressive visual loss and a membrane-like floater in the right eye that had persisted for 1 month. He had a history of eating raw foods, including snails. His initial visual acuity was counting fingers at 1 ft and he had a relative afferent pupillary defect. A movable larva with subretinal tracks was found in the subretinal space near a normal optic disc. Visually evoked potentials showed delayed latency, which indicated secondary retrobulbar optic neuritis. A diode laser was directly applied to the motile worm. The patient was subsequently prescribed oral prednisolone and albendazole. After treatment, his visual acuity was slightly improved at 2/60. Ocular manifestation is a very rare event resulting from parasitic infection. In only 1.1% of angiostrongyliasis cases is an Angiostrongylus cantonensis larva identified in the eye. Ocular angiostrongyliasis with optic neuritis may be secondary to mechanical injury and/or inflammatory reactions. Steroid treatment is recommended, although most patients have only slight visual improvement after treatment.Keywords: Angiostrongylus cantonensis, intraocular, ocular angiostrongyliasis, parasitic infectio
Laser-Induced Choroidal Neovascularizations: Clinical Study of 3 Cases
Background: We report 3 patients with laser-induced choroidal neovascularization (CNV). Method: Retrospective, observational case series. Medical charts and photographs were reviewed. Results: Two patients with central serous chorioretinopathy who developed iatrogenic CNV after focal laser photocoagulation were treated with intravitreal ranibizumab injections. One patient with CNV secondary to thermal laser photocoagulation for diabetic macular edema was treated with photodynamic therapy (PDT). Visual improvement has been demonstrated in the patients treated with intravitreal ranibizumab injections, and their successful visual outcome was stable for more than 2 years. Stable visual acuity was also observed in the patient treated with PDT, no visual improvement was observed possibly due to the macular scar and macular ischemia. No systemic or ocular complications were detected among the 3 cases. Conclusion: To prevent a laser-induced CNV, it is critical to avoid heavy small-spot laser burns and repeated application. Patients should be monitored carefully for CNV after laser treatment. In our cases, PDT and intravitreal ranibizumab injections were effective for the treatment of laser-induced CNV
Investigation On the Physical, Mechanical and Corrosion Behaviour of 316L Austenitic Stainless Steel Nitriding at Elevated Temperature
One of the most effective and economical ways to enhance the mechanical properties and corrosion behaviour of Austenitic Stainless Steel 316L series is through gas nitriding. The objective of this project covers the study of microstructure analysis of Austenitic Stainless Steel 316L, the mechanical strength of the nitrided and unnitrided Austenitic Stainless Steel 316L and as well as the corrosion behaviour of nitrided and unnitrided Austenitic Stainless Steel 316L
Systemic abnormalities associated with retinal vein occlusion in young patients
Suthasinee Sinawat,1 Chavisa Bunyavee,2 Tanapat Ratanapakorn,1 Supat Sinawat,3 Wipada Laovirojjanakul,1 Yosanan Yospaiboon1 1KKU Eye Center, Department of Ophthalmology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand; 2Department of Ophthalmology, Faculty of Medicine, Nawamindaradhiraj University, Bangkok, Thailand; 3Department of Physiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand Objectives: To study the systemic abnormalities associated with retinal vein occlusion in patients aged ≤50 years with a particular emphasis on atherosclerotic diseases and thrombophilic disorders. Methods: Medical charts of patients, aged ≤50 years whose diagnoses were retinal vein occlusions during the period 1995–2015 were retrospectively reviewed. The primary outcome was the number of systemic abnormalities associated with these patients. Secondary outcomes included types of retinal vein occlusion and sites of occlusion. Results: Atherosclerotic diseases were the most common systemic abnormalities associated with retinal vein occlusion and accounted for 55.1% of the patients in the study. Hypertension in 27.55%, diabetes mellitus in 16.33%, and 5.1% with dyslipidemia were noted. The number of thrombophilic disorders seemed to be less than expected and were noted in only 5.1%. Other systemic abnormalities included viral hepatitis infection, systemic lupus erythematosus, and acquired immunodeficiency syndrome. Oral contraceptives were used by some patients. Conclusion: Atherosclerotic diseases remained the most commonly associated systemic diseases in the majority of these patients. Approach to these patients should include a screening for hypertension, diabetes mellitus, and lipid abnormalities. Thrombophilia should also be considered where no obvious atherosclerotic diseases are found or if the patient is <40 years old, a history of thrombosis or a family history of thrombosis is possible. Keywords: retinal vein occlusion, systemic diseases, young patients 
Investigation On the Physical, Mechanical and Corrosion Behaviour of 316L Austenitic Stainless Steel Nitriding at Elevated Temperature
One of the most effective and economical ways to enhance the mechanical properties and corrosion behaviour of Austenitic Stainless Steel 316L series is through gas nitriding. The objective of this project covers the study of microstructure analysis of Austenitic Stainless Steel 316L, the mechanical strength of the nitrided and unnitrided Austenitic Stainless Steel 316L and as well as the corrosion behaviour of nitrided and unnitrided Austenitic Stainless Steel 316L
Histological analysis of gallbladder diseases in relation to opisthorchiasis in endemic areas of Thailand
Chronic gallbladder disease frequently accompanies infection with the liver fluke, Opisthorchis viverrini, in Northeast Thailand. However, the pathology and pathogenesis of the gallbladder disease have not been described. Accordingly, gallbladder specimens from 187 consecutive patients who had undergone cholecystectomy at a referral hospital in an endemic area in Thailand were histologically characterized in relation to O. viverrini infection. The infection was assessed by the presence of parasite eggs in the bile and/or antibody response to the liver fluke. The average level of parasite-specific IgG was significantly higher in patients with Opisthorchis eggs in the bile than those without (P < 0.001). The main histopathologic features of the gallbladder included inflammation, mucosal atrophy/or hyperplasia, goblet cell metaplasia, mucous gland hyperplasia, Rokitansky-Aschoff sinus formation, dysplasia and fibrosis. The fibrosis was strongly associated with elevated levels of Opisthorchis-specific antibody (P < 0.001) but not with the presence of parasite eggs. Other pathologic features did not vary in frequency or severity with parasitological status. Our results show that severe fibrosis of the gallbladder is a more common histologic feature of cholecystitis among those with O. viverrini infection compared to those without infection. The close relationship between parasite-specific IgG and severe fibrosis suggests that specific immune response to the parasite play an important role in the pathogenesis of the fibrotic change. (C) 2003 Elsevier B.V. All rights reserved
Macular sensitivity after half-dose verteporfin photodynamic therapy in central serous chorioretinopathy
Thuss Sanguansak, Prapapan Pitujaturont, Yosanan Yospaiboon, Suthasinee Sinawat, Tanapat Ratanapakorn, Chavakij Bhoomibunchoo Department of Ophthalmology, Faculty of Medicine, KKU Eye Center, Khon Kaen University, Khon Kaen, Thailand Objective: To study the macular sensitivity after half-dose verteporfin photodynamic therapy in patients with resolved central serous chorioretinopathy using the automated static perimeter.Methods: Prospective consecutive case study of 24 patients with resolved central serous chorioretinopathy was performed. The macular sensitivity was measured using a conventional automated static perimeter with the Swedish interactive threshold algorithm 10-2 and foveal threshold. Best corrected visual acuity, intraocular pressure, fundus examination, macular thickness, and volume were also examined. The mean macular sensitivities of the affected eyes and their normal fellow eyes were calculated and compared. P<0.05 was considered statistically significant.Results: The mean macular sensitivities of the affected eyes were lower than the normal fellow eyes with a statistically significant difference in all areas of the study (P<0.05). Best corrected visual acuity improved significantly from pretreatment (0.26±0.3 logMAR) to posttreatment (0.075±0.15 logMAR, P<0.05). Macular thicknesses in affected eyes were 230.66±67.34 µm and in the normal eyes were 238.33±92.26 µm (P=0.68). Macular volumes in affected eyes were 8.77±0.49 and in the normal eyes were 8.70±0.50 (P=0.60). These findings were not statistically significant.Conclusion: Eyes with resolved central serous chorioretinopathy after half-dose verteporfin photodynamic therapy had lower macular sensitivity than normal fellow eyes. These findings agreed well with the previous microperimetric studies. The conventional automated static perimeter can also be used when a microperimeter is not available. Keywords: macular sensitivity, half-dose photodynamic therapy, automated static perimeter, central serous chorioretinopath
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