Evaluation of cystatin capture ELISA and sodium metaperiodate antigen treated ELISA in diagnosis of toxoplasmosis

ELISA has become the mainstay for clinical serologic evaluation of toxoplasmosis. One of the major obstacles encountered in the evaluation of ELISA is the false-positive results due to immunological cross-reactions with other parasitic diseases that exhibit some lack of specificity. Evaluation of the diagnostic efficacy of two ELISA techniques: Cystatin capture ELISA and sodium metaperiodate treated antigen-ELISA [SMP-ELISA] compared to conventional ELISA, to detect IgG antibodies for crude T. gondii antigen in sera of toxoplasmosis patients. The study was carried out on 50 individuals categorized into three groups. Toxoplasmosis group included 30 patients confirmed by Sabin-Feldman dye test. Other parasitic diseases group included 10 sera from patients with amoebiasis [2], fascioliasis [2], hydatidosis [3] and schistosomiasis [3]. Control group included 10 healthy individuals. All sera under study were examined for the detection of T gondii IgG by three different ELISA techniques: Cystatin capture ELISA, SMP-ELISA amid conventional ELISA. The diagnostic performance of the three tests was statistically compared. Cystatin capture ELISA gave the best diagnostic results with 96.6% sensitivity, 95% specificity, 96.6% Positive Predictive Value [PPV], 95% Negative Predictive Value [NPV] and 96% diagnostic accuracy. In spite of the lower sensitivity and NPV of SMP-ELISA [86.6% and 82.6%, respectively] than the conventional ELISA, it had higher specificity [95%] and PPV [96.3%]. Cystatin capture ELISA improved the diagnostic performance of conventional ELISA in diagnosis of human toxoplasmosis

Role of aqueous humor matrix metalloproteinase-2 and its inhibitor and connective tissue growth factor in the pathogenesis of primary open angle glaucoma and pseudoexfolliative glaucoma

To study the presence and possible quantitative differences of matrix metalloproteinase-2 [MMP2] and its endogenous inhibitor, tissue inhibitor metalloproteinase-2 [TIMP2] and connective tissue growth factor [CTGF] in aqueous humor of patients with pseudoexfoliative glaucoma [PEXG], primary open angle glaucoma [POAG] and cataract patients [serving as controls] and to determine the potential role of these elements in the pathogenesis of glaucomas. Aqueous humor samples were collected from 75 patients [25 patients with PEXG, 25 with POAG and 25 with senile cataract, who served as controls]. Glaucoma and cataract subjects underwent routine glaucoma trabeculectomy and cataract extraction surgeries respectively. MMP2, TIMP2 and CTGF levels were measured using specific enzyme immunoassay [ELISA]. Total MMP2 was detected in significantly higher concentration in aqueous samples from PEXG eyes and POAG eyes compared to control eyes. The ratio of MMP2 to its principle inhibitor TIMP2 was balanced in cataract samples as well as in samples from PEXG glaucoma patients but increased in POAG samples. The CTGF concentration in PEXG group was significantly higher compared to POAG and cataract groups. Complex changes in MMP2- TIMP2 balance in aqueous humor may promote the abnormal matrix accumulation [in PEXG] and matrix degeneration [in POAG] which may be causally involved in the pathogenesis of both glucomas. The increased CTGF concentration supports the proposed fibrotic pathology of glaucoma. Regulation of MMP2/ TIMP2 expression and anti-CTGF therapy may offer potential therapeutic avenues for controlling glaucoma

Lipid peroxidation and antioxidant enzymes in diabetic retinopathy

Purpose: To investigate the role of oxidative stress in the development of diabetic retinopathy. The serum malondialdehyde [MDA] as an index of lipid peroxidation, the erythrocyte glutathione peroxidase [GPX] and superoxide dismutase [SOD] activity, were measured in 15 healthy control subjects and 30 diabetic patients [15 without retinopathy and 15 with diabetic retinopathy]. Serum MDA levels, erythrocytes GPX and SOD activity were estimated by specific colourimetric assays. Serum MDA levels were significantly elevated in diabetic patients compared with those in control subjects. Significant reduction in the activity of GPX was detected in diabetic patients when compared with control subjects. Patients with diabetic retinopathy showed a significant higher MDA level and lower GPX activity when compared with diabetics without retinopathy. Significant reduction in SOD activity was detected only in diabetic patients with retinopathy when compared with control subjects. Free radicals formation in diabetes mellitus which increases over time may play a role in the development of diabetic retinopathy, which is an important complication of the disease

DNA analysis of hepatocytes: a novel method for estimating the value of liver tissue vaccine [LTV]

Because of the socio-economic condition of African countries, the traditional types of vaccines should be encouraged. LTV in a preliminary study proved to be of value in reducing morbidity and mortality in Schistosoma mansoni infection. In the present study, and because of the vaccine contains liver tissue homogenate, the present study analyzed the DNA content of the hepatocytes of the vaccinated and control groups of animals to study any effects of the vaccine on the hepatocytes ploidy. The DNA content of vaccinated animals was high. The results were discussed. It was concluded that for testing S. mansoni vaccine, DNA analysis of hepatocytes for detecting proliferative S-phase is an important as a positive immune reaction

Studies on house dust mites in great Cairo, Egypt

House dust mites were collected from 8 different areas in Great Cairo. Nine species of mites were recovered from indoors. In order of abundance, they were Dermatophagoides pteronyssinus, D. farinae, Tyrophagous putrescentiae, Acarus siro, Cheyletus malaccensis, Blomia kulagini, Acheles graciles, Ornithonyssus bacoti and Lepidoglyphus destructor. All these mites were collected mainly from Bulaq El- Dakrour [28.8%] and El-Wayly [27.6%]. The least number [1.8%] of species [only 3] was collected from Madent El-Salam. Pet and stray dogs and cats, domestic birds and commensal rodents were more or less reported in the majority of the examined areas. Also, patients with history of allergy of unknown cause were reported in 10 out of 80 houses examined [12.5%]. The role played by house dust mites in causing allergic manifestations was important environmental disease agents

use of a modified compression shell after subscleral trabeculectomy

To determine the influence of a modified compression shell [with a cut out free space for the cornea] in guarded filtration procedures on flat anterior chambers, final intraocular pressure [IOP] reduction, success rate, tenon capsule cyst [TCC] and bleb appearance in patients with primary open angle glaucoma, we randomized in a prospective clinical trial 33 patients divided into two groups: Group A, 15 patients in whom the shell was applied immediately postoperatively; and group B, 18 patients without shell. Both groups were similar in age, sex, diagnosis and preoperative IOP. The shell was applied at the end of each surgery and used for three days postoperatively. There was no statistical difference after surgery in the incidence of flat anterior chamber [2/15 in group A and 3/18 in group B]. Also, there was no difference after three months in term of bleb appearance, but there was a tendency of fewer TCC in those receiving the shell [1/15 in group A and 3/18 in group B]. After two years there was no statistical difference in IOP reduction or in success rate in either group [73.5 percent group A and 72.5 percent group B]. Success is defined as 5 mmHg <22, with reduction of medication and no carbonic anhydratse inhibitors

Visual field changes in common and classic migraine

To detect whether migraine has any permanent effect on the visual field [VF], 25 cases of classic migraine with visual aura and 10 cases of common migraine were examined. All cases were examined between the attacks. The results showed that 40 percent of cases had permanent VF abnormalities not statistically related to age, sex or duration of the disease. VF abnormalities are more common among classic migraineurs. Permanent neurological effects on the visual pathway caused by migraine are due to prolonged or severe vasospasm of the external carotid and ophthalmic arteries or of the basilar vascular system. Cases with unilateral VF abnormalities were mostly caused by vasoconstriction of the external carotid and the ophthalmic arteries, [anterior visual pathway migraine type]. Also, most of the cases with bilateral VF abnormalities were caused by vasoconstriction of the basilar vascular system, [posterior visual pathway migraine type]. Visual field plotting in these patients, proved to be most effective in localising the site of vasoconstriction