Comparative evaluation of surface roughness of posterior primary zirconia crowns.

AIMS: To compare the surface roughness of four commercially available posterior zirconia crowns on the occlusal surface and occlusal edge (buccal cusps) of first and second primary molars crowns. METHODS: Surface roughness of 40 posterior primary zirconia crowns was measured using a mechanical stylus profilometer. Ten mandibular right molar crowns, consisting of five first primary molar and five second primary molar crowns from four brands-Cheng, Sprig EZCrowns, NuSmile and Kinder Krowns were selected. Mean roughness, Ra and mean roughness depth, Rz was measured for all crowns on two selected surfaces, occlusal surface and buccal cusp tips. Data was evaluated by one way analysis of variance and Tukey's honestly significant difference test at 0.05 level of significance. RESULTS: Statistically significant differences were observed in the mean Ra and Rz values at both selected surfaces among four prefabricated paedodontic zirconia crowns. Kinder Krowns had higher Ra and Rz values compared to Cheng, Sprig EZCrowns and NuSmile. Roughness profile of Kinder Krowns also showed higher vertical scale values co-relating with higher Ra and Rz scores, irrespective of the measurements taken on relatively flat surfaces (occlusal edge) or deeper surface (occlusal pits and fissures). CONCLUSIONS: Mechanically polished posterior primary zirconia crowns had a smoother surface profile than the combined polished-glazed primary zirconia crowns. Cheng Crowns had the lowest mean Ra and Rz values although not statistically significant from Sprig EZCrowns and Nu Smile. Kinder Krowns had the highest mean Ra and Rz scores than other crown groups.

Toxoplasma genotyping in congenital toxoplasmosis in Upper Egypt: evidence of type I strain.

Toxoplasma gondii has subpopulation structures in different geographical regions caused by less frequent sexual recombination, population sweeps, and biogeography. The majority of strains isolated in North America and Europe fall into one of three clonal lineages, referred to as types I, II, and III. So far, little is known about genetics of Toxoplasma strains in Africa. The present study aimed to determine the genotype of Toxoplasma strains obtained directly from trophoblastic/placental tissues of 29 complicated pregnant women using multilocus nested-PCR-RFLP technique depending on four independent genetic loci (5' SAG2 and 3' SAG2), SAG3, GRA6, and BTUB genes. All samples gave positive amplicons at 5'-3' SAG2 and SAG3 genes. Meanwhile, no amplification products were observed in 12 (41.37%) and 10 (34.48%) samples with GRA6 and BTUB genes, respectively. The restriction pattern revealed the presence of genotype I in all samples, except one sample, which revealed atypical genotype with unusual restriction pattern at 3' SAG2 gene. The negative amplifications in some samples could be due to presence of mutations or polymorphisms in the primer binding sites of these isolates, raising the possibility of mixed or recombinant genotypes. To the best of our knowledge, this is the first time to perform genotype analysis study based on Multiplex nPCR-RFLP technique for genetic characterization of T. gondii in Egypt. Besides, it is the first time to prove that the most prevalent strain of T. gondii, responsible for congenital toxoplasmosis in Upper Egypt, is the highly virulent type I. Atypical genotype was detected as well.

Comprehensive growth performance, immune function, plasma biochemistry, gene expressions and cell death morphology responses to a daily corticosterone injection course in broiler chickens.

The massive meat production of broiler chickens make them continuously exposed to potential stressors that stimulate releasing of stress-related hormones like corticosterone (CORT) which is responsible for specific pathways in biological mechanisms and physiological activities. Therefore, this research was conducted to evaluate a wide range of responses related to broiler performance, immune function, plasma biochemistry, related gene expressions and cell death morphology during and after a 7-day course of CORT injection. A total number of 200 one-day-old commercial Cobb broiler chicks were used in this study. From 21 to 28 d of age, broilers were randomly assigned to one of 2 groups with 5 replicates of 20 birds each; the first group received a daily intramuscular injection of 5 mg/kg BW corticosterone dissolved in 0.5 ml ethanol:saline solution (CORT group), while the second group received a daily intramuscular injection of 0.5 ml ethanol:saline only (CONT group). Growth performance, including body weight (BW), daily weight gain (DG), feed intake (FI) and feed conversion ratio (FC), were calculated at 0, 3 and 7 d after the start of the CORT injections. At the same times, blood samples were collected in each group for hematological (TWBC's and H/L ratio), T- and B-lymphocytes proliferation and plasma biochemical assays (total protein, TP; free triiodothyronine hormone, fT3; aspartate amino transaminase, AST; and alanine amino transaminase, ALT). The liver, thymus, bursa of Fabricius and spleen were dissected and weighed, and the mRNA expression of insulin-like growth factor 1 gene (IGF-1) in liver and cell-death-program gene (caspase-9) in bursa were analyzed for each group and time; while the apoptotic/necrotic cells were morphologically detected in the spleen. From 28 to 35 d of age, broilers were kept for recovery period without CORT injection and the same sampling and parameters were repeated at the end (at 14 d after initiation of the CORT injection). In general, all parameters of broiler performance were negatively affected by the CORT injection. In addition, CORT treatment decreased the plasma concentration of fT3 and the mRNA expression of hepatic IGF-1. A significant increase in liver weight accompanied by an increase in plasma TP, AST and ALT was observed with CORT treatment, indicating an incidence of liver malfunction by CORT. Moreover, the relative weights of thymus, bursa and spleen decreased by the CORT treatment with low counts of TWBC's and low stimulation of T & B cells while the H/L ratio increased; indicating immunosuppressive effect for CORT treatment. Furthermore, high expression of caspase-9 gene occurred in the bursa of CORT-treated chickens, however, it was associated with a high necrotic vs. low apoptotic cell death pathway in the spleen. Seven days after termination of the CORT treatment in broilers, most of these aspects remained negatively affected by CORT and did not recover to its normal status. The current study provides a comprehensive view of different physiological modulations in broiler chickens by CORT treatment and may set the potential means to mount a successful defense against stress in broilers and other animals as well.

Lithium chloride-induced cardiovascular changes in rabbits are mediated by adenosine triphosphate-sensitive potassium channels.

The effect of lithium chloride on the mean arterial blood pressure, heart rate and heart contractility was evaluated in rabbits. The intravenous administration of 50 mg kg-1 lithium chloride as a bolus injection into rabbits produced a progressive decrease in the mean arterial blood pressure, heart rate and heart contractility during the 2-h period of investigation. Pretreatment of animals with 5 mg kg-1 glibenclamide, a potent inhibitor of adenosine triphosphate-sensitive potassium channels, markedly inhibited the cardiovascular changes induced by lithium chloride. Doubling the dose of glibenclamide nearly abolished these effects of lithium chloride. Similarly, lithium chloride produced a concentration- dependent relaxation of noradrenaline-induced contractions in isolated aortic strips of rabbits. This relaxant effect of lithium chloride was inhibited by pretreatment of the aortic strips with glibenclamide. Doubling the concentration of glibenclamide in the bathing fluid nearly abolished the effect of lithium. Diazoxide and verapamil potentiated the relaxant effect of lithium chloride on the isolated noradrenaline-contracted aortic strips. Pretreatment with glibenclamide markedly reversed the effect of diazoxide but not that of verapamil. The intravenous administration of lithium was also found to be capable of increasing the plasma potassium level and of decreasing the intracellular levels of adenosine triphosphate in cardiac and vascular tissues in a time-dependent manner. The plasma sodium and calcium levels were not changed. These results provide evidence that the hypotensive and cardiac depressant effects of lithium chloride are mediated by activation of adenosine triphosphate-sensitive potassium channels.

Radio-immuno assay estimation of plasma endothelin levels in patients with bilharzial and post viral liver cirrhosis: a possible new additive factor in aggravation of portal hypertension.

Radio immunoassay estimation of plasma endothelin level was carried out in 90 patients with bilharzial and post viral chronic liver diseases with portal hypertension associated with bleeding and non bleeding oesophageal varices as well as 10 normal control subjects. It was found that plasma endothelin level was significantly elevated in such patients when compared to normal controls. Moreover, there was a positive correlation between the elevated levels of plasma endothelin and portal vein diameter as well as bleeding oesophageal varices. It may be concluded that plasma endothelin, which is a very potent vasoconstrictor for both systemic and portal circulation, plays an important role in aggravation of portal hypertension in liver cirrhosis.

Risk of hepatitis "E" virus infection among some schistosomiasis patients in Egypt.

This study was carried out to demonstrate hepatitis "E" virus antibodies (IgG) among individuals living in different rural areas. The study included 200 individuals. One hundred were suffering from S. mansoni as confirmed by stool egg count, rectal snip, abdominal ultrasound and liver biopsy. The second hundred (Group II) were parasite-free individuals serving as normal control. The main symptoms of group I were dyspepsia, fatigue, dysentery, bleeding per rectum and hepatomegaly. There was no significant difference in the transaminase levels (SGPT and SGOT) between both groups. The prevalence of HEV-ab (ab (IgM) among group I was 31% and group II, 14% with a highly significant increase in group I. There was no correlation between the number of egg count in stools and HEV infectivity. Thus, the prevalence of HEV was higher in the rural areas and in schistosomiasis patients in particular, due to low sociohygienic conditions under which the patients are living. Also schistosomiasis may play a role in virus infection by altering the immune system.

Four species of house dust mites recovered from houses of patients with allergic respiratory diseases.

Arthropods and their products are wide spread and considered one of the common allergens affecting man. Allergy to arthropod antigens is the major cause of respiratory allergy as rhinitis and bronchial asthma. The range of reaction depends on several factors which include the type and source of the material, the rate of intensity, the duration of exposure, the human immune response and history of prior exposure. Successful management of allergic disease depends on proper identification of the causative allergen and reduce exposure to this allergen. Generally speaking, the house dust is not a simple substance but an accumulation of living and non living parts as mites, pollens, molds, dander and decaying insects. In the present study, four species of mites were isolated from the dust collected from the houses of patients with allergic respiratory diseases. The species were Dermatophagoides pteronyssinus, D. farinae, Ornithonyssus bacoti and Haemogamassus pontiger. The two species of Dermatophagoides. were the predominant mites which are known to produce the most potent allergies. Studying the serum immunoglobulins level showed that the IgE had a highly significant concentration among respiratory allergic patients (28) with (5) or without (23) atopic dermatitis. It was concluded that house dust mites, that cause inhalant allergens, are one of the main aetiological factors of allergic respiratory diseases, with or without atopic dermatitis.

Cytophotometric estimation of hepatocytes DNA in chronic liver diseases including schistosomiasis for detection of early preneoplastic changes.

No doubt chronic liver diseases due to schistosomiasis and other causes as virus hepatitis are not uncommon among Egyptian patients. Besides, neoplastic changes in such patients are always seen. So, the aim of this work was to evaluate the estimation of hepatocytes DNA in chronic liver diseases as a diagnostic feature for early preneoplastic changes in different groups of patients. These groups included (a) chronic persistent hepatitis, (b) chronic active hepatitis, (c) liver cirrhosis due to schistosomiasis and other causes & (d) hepatocellular carcinoma. The results were evaluated histochemically and histopathologically. It was concluded that the cytophotometic evidence of hepatocytes DNA in chronic liver diseases is a promising mean in detecting early preneoplastic changes.

Immunofluorescent diagnosis of Chlamydia trachomatis infection of the respiratory tract and the eye.

Direct and indirect immunofluorescent antibodies as well as IgM antichlamydia antibodies were studied for diagnosis of 60 patients with Chlamydia trachomatis infection as well as 20 normal controls (group C). 30 Patients were suffering from C. trachomatis pneumonia (group A) and the other 30 patients were suffering from trachoma eye infection (group B). Indirect immunofluorescent technique (IIF) was positive 9.9% of group A. IgM antichlamydia antibodies by ELISA was positive in 23.3% and 16.6% in group "A" and "B" respectively. While highly positive results (60%) were obtained in conjunctival smears of group "B" when using direct immunofluorescent staining.

Immunocytological detection of T-lymphocyte subpopulation in schistosomiasis mansoni patients.

Pan T-lymphocytes, T4 (helper cells), T8 (suppressor cells) and T4/T8 ratio were studied in 51 bilharzial patients as well as 30 healthy controls using monoclonal antibodies and indirect immunofluorescence technique. There was no significant alteration in cell mediated immunity in early non complicated schistosomal infection with the advance of the disease and the development of granuloma cell mediated immunity was markedly decreased as evidenced by significant reduction in pan T-lymphocytes, T4 (helper) cells as well as T4/T8 ratio in hepatosplenic group in comparison to healthy controls. Splenomegaly in such cases may play an addtiinoa lrole in the immunosuppression.

Plasma fibronectin and serum complement C3 levels in chronic active hepatitis following virus "B" versus virus "C" infection.

Plasma fibronectin and serum complement C3 levels were estimated in 30 patients with chronic active hepatitis (CAH) post virus "B" and another 30 patients with CAH post virus "C" as well as 20 normal healthy subjects. Fibronectin level was significantly increased in CAH when compared to normal controls. Moreover, fibronectin level was significantly increased in CAH following virus "C" when compared to CAH following virus "B" hepatitis. Concerning complement C3 there was no significant changes in the different groups studied. We may conclude that CAH following virus "C" may lead to vigorous inflammatory damage than CAH following virus "B" infection.

Delta virus versus HBsAg in chronic active hepatitis and their relation to clinical, laboratory, and morbidity findings in bilharzial and non-bilharzial patients.

This work was done to study the effect of delta virus and HBV infection, as two aetiological factors on clinical presentation, biochemical liver functions and prognosis of chronic active hepatitis (CAH) in schistosomiasis infected and non-infected patients. 66.7% of the patients were carriers for HBsAg, among them 41.7% were infected with delta virus. It was evident that the clinical presentation of the patients with positive serological markers of HBV and HDV demonstrated advancing liver disease than in the other studied groups. Moreover, the biochemical liver profile was significantly affected when the triad of chronic HBV, delta virus and schistosomiasis infection was present. This could be related to the immunosuppression caused by schistosomal infection. Furthermore, mortality rate was significantly higher in schistosomiasis infected individuals.

Assessment of serum copper and zinc levels in chronic Schistosoma mansoni patients with and without hepatic involvement before and after praziquantel therapy.

Estimation of serum copper and zinc was carried out on 40 Schistosoma mansoni patients with and without hepatosplenic involvement (group A and B respectively) before and after single oral dose of 40 mg praziquantel therapy as well as 20 normal controls (group C). Full clinical examination and assessment of liver function tests was done. HBsAg positive cases were excluded. The results showed a significant increase in the copper level in both groups (A and B) before treatment when compared to normal controls, and a significant reduction in zinc level only in group B. Following praziquantel therapy the copper level decreased with concomitant increase in the serum zinc level.

Profile of portal hypertension in hepatosplenic schistosomiasis.

Intrasplenic pressure changes versus ova count in stool of schistosomal portal hypertension in cases of bilharzial hepatic fibrosis were studied before and after 40 mg/kg body weight praziquantel therapy. Praziquantel acts on the vascular level in which it decreases the portal hypertension caused by bilharziasis as detected by decreased size of portal and splenic veins diameter as well as a significant decrease of portal pressure by the decrease of intrasplenic pressure (P less than 0.05). On the other hand, praziquantel decrease bilharzial stool egg count after 3 months of therapy (P less than 0.05).

Prolactin imbalance as a result of bilharzial hepatosplenomegaly.

Prolactin is an important hormone for maintenance of normal sexual life in human. Prolactin is produced in the lactotropic cells in the lateral wing of the anterior pituitary gland. Prolactin imbalance associated with bilharzial hepatosplenomegaly with subsequent infertility was carried out on sixty female patients and 30 normal controls. In bilharzial patients and 30 normal controls. In bilharzial patients with hepatosplenomegaly, there was hyperprolactinaemia in 13.33% of cases. 10% of patients suffering from bilharzial hepatosplenomegaly had primary infertility and 70% had secondary infertility more than 5 years. Galactorrhea was present in 10% of cases with bilharzial hepatosplenomegaly. There was irreversible relationship between the duration of bilharzial infection and serum prolactin level and inability to conceive, and also between the duration of bilharzial infection and endocrine manifestations as infrequency and irregularity of menstruation.

Assessment of recent techniques in diagnosis of chronic hepatic disorders.

One hundred and one patients with bilharzial complication were selected and subjected to ultrasonography (U.S.), computed tomography (C.T.) and laparoscopy. Laparoscopy proved to be the most reliable technique in diagnosis of early pure bilharzial hepatic affection and is more specific compared to both U.S. and C.T. (P less than 0.05). U.S. proved to be more reliable than C.T in diagnosis of diffuse hepatic disorders. CT/or US are more specific in diagnosis of focal than diffuse liver diseases. CT proved to be more reliable than U.S. in detecting primary hepatocellular carcinoma and in assessment of hepatic spread.

Some immuno-pathological aspects in bilharzial and amoebic dysentery.

Serum immunoglobulin, secretory IgA in stools and leucocyte migration inhibition test were done for 75 patients suffering from bilharzial and amoebic dysentery as well as 20 normal controls. Sigmoidoscopic examination with immunofluorescent staining of colonic biopsy was done in patients with bilharzial dysentery. Humoral immune response increased significantly as detected by significant increase in serum IgG and IgM. Secretory IgA decreased significantly in bilharzial cases leucocyte migration inhibition test decreased significantly as well as plasma cells secreting IgA. This change in systemic and local immune response may predispose to infection or occur secondary to the disease.