Effect of Using Biomimetic Analogs on Dentin Remineralization with Bioactive Cements

Abstract This study evaluated the impact of using biomimetic analogs (poly-acrylic acid and sodium tri-meta-phosphate) on dentin remineralization using two cement materials, the first is calcium silicate based and the second is calcium hydroxide based materials. Two standardized occlusal cavities (mesial and distal) were prepared within dentin after removal of occlusal enamel. Artificial demineralized dentin was induced through pH cycling (8 h in demineralizing and 16 h in remineralizing solutions). Demineralized cavities were divided into four groups; two groups received cement materials. The other groups were first treated with biomimetic analogs then restored with pulp cement materials. Teeth were sectioned buccolingually into two halves. Treated cavities with analogs were stored in simulated body fluid containing poly-acrylic acid. Untreated cavities were stored in simulated body fluid only. Ground unstained sections of demineralized dentin were examined using light microscope. Specimens were examined after 1, 6 and 12 weeks of storage using energy dispersive X-ray Spectroscopy (EDX) and Vickers microhardness was evaluated. Two-way ANOVA was used to analyze data statistically. Calcium silicate-based cement group with biomimetic analogs showed the highest statistically significant calcium and phosphorous wt% in addition to highest surface hardness values after 12 weeks of storage. Demineralized dentin ground sections showed increase in light zones after total period of storage. Calcium silicate-based cement showed the best ability to enrich the artificial carious dentin with ions for remineralization. Using biomimetic analogs had a significant impact on demineralized dentin surface hardness improvement.

Resumo Este estudo avaliou o impacto do uso de análogos biomiméticos (ácido poli-acrílico e tri-meta-fosfato de sódio) na remineralização da dentina usando dois materiais de cimento, o primeiro à base de silicato de cálcio e o segundo à base de hidróxido de cálcio. Duas cavidades oclusais padronizadas (mesial e distal) foram preparadas na dentina após a remoção do esmalte oclusal. A dentina desmineralizada artificial foi induzida por ciclagem de pH (8 h em soluções desmineralizantes e 16 h em soluções remineralizantes). Cavidades desmineralizadas foram divididas em quatro grupos; dois grupos receberam materiais de cimento. Os outros grupos foram tratados primeiro com análogos biomiméticos e depois restaurados com materiais de cimento de celulose. Os dentes foram seccionados bucolingualmente em duas metades. As cavidades tratadas com análogos foram armazenadas em fluido corporal simulado contendo ácido poli-acrílico. As cavidades não tratadas foram armazenadas apenas em fluido corporal simulado. Secções não coradas de dentina desmineralizada foram examinadas usando microscópio óptico. As amostras foram examinadas após 1, 6 e 12 semanas de armazenamento usando Espectroscopia de Raios-X dispersiva por energia (EDX) e microdureza Vickers. ANOVA a dois fatores foi usada para analisar os dados estatisticamente. O grupo de cimento à base de silicato de cálcio com análogos biomiméticos apresentou os maiores percentagens em peso estatisticamente significantes de cálcio e fósforo, além dos maiores valores de dureza superficial após 12 semanas de armazenamento. Seções desmineralizadas de dentina mostraram aumento nas zonas de luz após o período total de armazenamento. O cimento à base de silicato de cálcio mostrou a melhor capacidade de enriquecer a dentina cariada artificial com íons para remineralização. O uso de análogos biomiméticos teve um impacto significativo na melhoria da dureza superficial da dentina desmineralizada.

FLT3 Mutations: Significance in Paediatric AML

Patients with acute myeloid leukaemia (AML) who have FMS-like tyrosine kinase 3 (FLT3) mutations are a concern for haematologists. Many studies indicate that these patients have poor prognosis. Due to the dearth of research in this area, the role of allogeneic transplantation as a therapy is still controversial. But the available limited data suggest that transplantation in first remission is possibly the first choice. As FTL3 mutations in AML result in poor patient outcomes, different FLT3 inhibitors are used as specific targeted therapy.

Diagnosis of major bacterial causes of culture negative meningitis in children

The study included 250 patients admitted to fever hospitals in Egypt with suspected clinical signs and symptoms of bacterial meningitis, their age ranged from six months up to eleven years. Cerebrospinal fluid [CSF] samples isolated from patients were transported to the central health laboratories for confirmation of diagnosis. Physical, cytological, chemical examination for glucose and total protein concentration. Gram stained smear, culture on blood and chocolate agar were done. 62 [24.8%] CSF samples were culture negative and no bacterial organisms could be detected by direct gram stain. All these samples were further examined by latex agglutination and RT-PCR. Samples which found to be culture positive were excluded from this study. 15 samples of them [24.2%] were positive by RT-PCR.7 of them [46.6%] were Heamophilus influenza b [H. influenza b] and 8 samples of them [53.3%] were Streptcoccus pneumoniae [S. pneumoniae]. Out of 15 RT-PCR positive samples 12 of them [80%] were Latex positive, while 3 of them [20%] were Latex negative, one of the three was S. pneumoniae, while the others were H. influenza b by RT-PCR only. Out of 62 culture negative CSF samples 47 [75.8%] had a history of previous antibiotic use. 11samples of them [23.4%] were positive by latex agglutination [5 samples were H. influenza b and 6 samples were S. pneumonia] and 3 samples of them [6.3%] were positive by RT-PCR and negative by latex agglutination. Out of 15 RT-PCR positive samples, 8 of them were clear [53.3%], 3 of them were turbid [20%], and 4 of them were bloody [26.6%]. 10 CSF samples out of the 15 samples [66.6%] had normal cytological profile, 6 samples [40%] had normal CSF glucose levels and 3 samples [20%] had normal total CSF protein concentration

Synthesis and characterization of laminated Si/SiC composites

Laminated Si/SiC ceramics were synthesized from porous preforms of biogenous carbon impregnated with Si slurry at a temperature of 1500[degree]C for 2 h. Due to the capillarity infiltration with Si, both intrinsic micro- and macrostructure in the carbon preform were retained within the final ceramics. The SEM micrographs indicate that the final material exhibits a distinguished laminar structure with successive Si/SiC layers. The produced composites show weight gain of approximately 5% after heat treatment in air at 1300[degree]C for 50 h. The produced bodies could be used as high temperature gas filters as indicated from the permeability results

Pancreatic cancer in Saudi patients treated at tertiary institution. Ten years retrospective study

To describe presentation, management, and outcome, and determine prognostic factors for pancreatic cancer patients. A retrospective review of patients diagnosed with pancreatic cancer at King Abdulaziz Medical City, Riyadh, Saudi Arabia during the period from January 2000 to December 2010. Descriptive statistics were conducted on the collected data and survival was estimated using the Kaplan Meier estimate. Univariate and multiple regression analyses were carried out. The medical records of 179 patients were reviewed. The patients' median age was 63 years ranging from 15-96 years, and 116 [64.8%] of them were male. The one-year survival rate was 39% and the 5-year survival was 10%. The median overall survival [OS] was 6.9 months. Age at diagnosis, grade, T stage, N stage, M stage, TNM stage group, and the combined stage group [stage III/IV versus others], site of distant metastasis, carcinoembryonic antigen [CEA], carbohydrate antigen 19-9, surgery and chemotherapy were significant predictors for OS on an univariate Cox proportional hazards regression analysis. A multiple regression model including all the significant predictors was conducted. Age at the time of diagnosis and M stage were significant variables. Our patients present at a younger age and have better 5-year survival compared with the United States Surveillance Epidemiology and End Results data, which deserves further evaluation. Age and disease stage were identified as independent prognostic factors for survival in this patient population

first national public breast cancer screening program in Saudi Arabia

Despite its relatively low incidence in Saudi Arabia, breast cancer has been the most common cancer among Saudi females for the past 12 consecutive years. The objective of this study was to report the results of the first national public breast cancer screening program in Saudi Arabia. Women 40 years of age or older underwent breast cancer screening. Mammograms were scored using the Breast Imaging-Reporting and Data System [BI-RADS]. Correlations between imaging findings, risk factors and pathological findings were analyzed. Between September 2007 and April 2008, 1215 women were enrolled. The median age was 45 years, and median body mass index was 31.6 kg/m[2]. Sixteen cases of cancer were diagnosed. No cancer was diagnosed in 942 women with R1/R2 scores, and only 1 case of cancer was diagnosed in 228 women with R0/R3 scores. However, among 26 women with R4/R5 scores, 50% had malignant disease and 35% had benign lesions. No correlation was found between known risk factors and imaging score or cancer diagnosis. Public acceptance of the breast cancer screening program was encouraging. Longitudinal follow-up will help in better determining the risk factors relevant to our patient population

Determination of antigenic patterns of three taenia extracts and their use for differential diagnosis of taeniasis by immunoblot

Immunoserological differential diagnosis of Taenia spp. is the major contribution of the present work. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis [SDS-PAGE] was used to analyze the protein components of three Taenia extracts prepared from Cysticercus bovis, Taenia saginata and Taenia taeniaeformis. Antigenic components of the three taeniid antigens revealed by [SDS-PAGE] were: [I] Cysticercus bovis cystic fluid antigen: 180, 116, 90, 66, 45, 26, 17 and 10 kD. [II] Taenia saginata excretory secretory antigen [ES]: 198, 180, 146, 116, 55, 45, 35 and 26 kD. [III] Taenia taeniaeformis whole crude antigen 170, 140, 120, 116, 66, 55, 45, 35, 26, 17 and 10 kD. The characterized extracts were used as antigens in Western Blot [WB] technique. Sera from immunized rabbits with Cysticercus bovis fluid antigens were used in detecting a variety of immunogenic bands: [I] Cysticercus bovis: 160, 116, 86, 52, 45, 38 and 29 kD. [II] Taenia saginata: 86, 68 and 10 kD. [III] Taenia taeniaeformis: 170, 116, 86, 68, 52, 45 and 29 kD. The present results suggested that the diagnostic bands by Western Blotare 160 and 38 kD for Cysticercus bovis, 10 kD for Taenia saginata [ES] antigen and 170 kD for Taenia taeniaeformis

Coproantigen versus EGG antigen in immunodiagnosis of intestinal capillariasis using Western Blot Technique

Capillaria philippinensis is a zoonotic nematode that causes severe diarrheal syndromes in humans. C. philippinensis coproantigen and egg antigen were fractionated using SDS-PAGE. Several protein bands were detected in both antigens. Protein profile of coproantigen of C. philippinensis infected patient included wide range of bands ranging from 10- 180 kD. Protein profile of egg antigen revealed only few bands detected at 10, 34- 36.5, and 148 kD. Using Western blot, a variety of protein bands were recognized by the infected patient serum. When tested against coproantigen, it detected a wide range of antigenic proteins at different molecular weight [10, 14, 34-36.5, 48, 54, 62, 66, 86, 94, and 148 kD respectively]. None of these bands were detected in normal human feces. When tested against egg antigen, the infected patient serum detected only two faint antigenic bands at 62 and 66 kD. It is concluded that coproantigen was more convenient than egg antigen in diagnosis of capillariasis by WB

Human muscle sarcocystosis in relation to non specific rheumatic diseases and rheumatoid arthritis

Human muscle sarcocystosis is a parasitic infestation acquired by ingestion of the sporocysts of the sarcocystis species. Sarcocystis antibodies were said to be encountered in patients with connective or mixed connective tissue disorders. Parasitological etiology of musculoskeletal disorders may help to modify the line of treatment of these patients. This study was performed on 22 non specific rheumatic patients, 21 rheumatoid arthritic [RA] patients and 10 apparently healthy persons as controls. Using the sarcocystis fusiformis antigen [Ag.], serum samples of the patients were tested for the presence of sarcocystis species antibodies using the Westren Blot technique. Of the 22 patients of the first group, 14 were positive [63.7%], of the 21 patients of the second group 5 were positive [23.8%]. They deducted several band ranges from 15-116 KD. Most of these samples had eosinophilia ranging from 7-20%. None of the control group serum reacted against sarcocystis Ag. Statistically the difference between the two groups was significant [P <0.04]. Sarcocystis infection may be an important cause of the non specific rheumatic diseases associated with myositis. Diagnosis and treatment of such a frequent infestation in carefully chosen cases would relieve them from prolonged intake of antirheumatics and their side effects

Prevalence of cysticercus bovis and effect of cooking on its viability

Taenia saginata infection is found wherever raw or undercooked beef is eaten. Supervised slaughtering and good methods of cooking can control infection. Random samples of bovine meat and serum were collected from 100 cattle slaughtered in Assiut abattoir and inspected for Cysticercus bovis. Infected samples were processed for different methods of cooking and the viability of the cysts was estimated. The prevalence of infection was [8%] and [29%] by inspection and serology respectively. Boiling is a safer cooking, grilling and braising are susceptible while roasting is risky when rare-done

Light microscopic study of the effect of flubendazole, praziquantel and combination of both drugs on adult schistosoma mansoni [with 14 figures]

It is considered that combination of chemotherapy with other control measures can reduce transmission and morbidity of schistosomiasis. This study was done using 60 albino mice infected with cercariae of Schistosoma mansoni. Mice were divided into 4 groups [control, flubendazole treated, praziquantel treated and combination of both drugs]. The effect of treatment was evaluated on male and female worms after [1, 2 and 3 Week Post Treatment]. Worms were collected by perfusion of portal vein and mesenteric veins separately, stained with acetic acid alum carmine and examined by light microscope

Scanning electron microscopy of adult schistosoma mansoni after treatment with praziquantel, flubendazol and combination of both [with 4 plates]

Many antischistosomal drugs are known to cause changes in the ultrastructure of adult worms. This study was done using 60 albino mice infected with cercariae of Schistosoma mansoni. Mice were divided into 4 groups [Control, Flubendazole-treated, Praziquantel-treated and the last group treated by combination of both drugs]. The effect of treatment was evaluated on male and female worms after one and three weeks post treatment. Worms were collected by perfusion of portal vein and mesenteric vein separately then examined by scanning electron microscopy

Possible causes of morphometric differences in Schistosoma haematobium eggs in Sohag [Upper Egypt]

Eggs of Schistosoma spp. are of particular taxonomic importance. Minor variations in morphometry of egg or spine may denote a different species, variety or strain. Eggs of Schistosoma haematobium were detected from five urinary bilharzial cases. They were of different ages [6-29 years old] and different worm burdens [egg count varied from 5-375 eggs/1ml urine]. Previous treatment was also taken in consideration. Eggs were subjected to microscopical examination. Wide variations were observed in the egg measurements. Abnormal morphology was also observed Unfertilized eggs were observed for the first time. These were generally smaller in size than fertile eggs, and showed some deformity in their outline and contain few different- sized refractile granules. It is concluded that S. haematobium in Egyptian patients may belong to different strains that have eggs variable in measurements and shapes. Cross-fertilization between different species may affect the morphometry of the resultant eggs and may also be responsible for the deformities described during the present study

Detection of schistosoma haematobium egg antigen by western blot

Eggs of Schistosoma release a potent soluble egg antigen SEA" which is used as an important marker in immunodiagnosis of schistosomiasis. Electrophoresis and identification of different protein fractions of the antigen are used in accurate serological diagnosis. This work aimed to detect Schistosoma haematobium egg antigens in human serum and hyperimmune sera of rabbits by Western blot [WB]. The results revealed important bands detected with rabbit anti-sera against [SEA] at 32-34, 40, 63 and 100 KD. In case of human anti-sera, the most important bands were at 24-26, 32-34, 40, 63 110 and 150 KD. This work was done for the first time in Egypt and its results agreed with what was done before by other methods

Scanning electron microscopical studies on some metacercariae of family clinostomatidae

Clinostomatid species metacercariae are commonly found in Tilapia species. Three species of the family Clinostomatidae were observed where Clinostomum complanatum, Clinostomum phalacrocoracis and, Euclinostomum ardeolae were studied at the ultrastructural level using the scanning electron microscope. These parasites were collected from the pharyngeal region, body muscles and kidneys of Tilapia nilotica fish obtained from fish dealers. The shape of metacercariae, sensory papillae found on their surfaces, and the shape of their suckers and excretory pores showed marked difference between the three species. The present work provided some important morphological information's for comparison between three metacercariae of the family Clinostomatidae by the use of scanning electron microscope [SEM]. It also explained the mechanism of attachment of clinostomum complanatum to the host tissues and suggested that the genus Euclinostomum may have the same methods of absorption of glucose as the genus Clinostomum

Immunodiagnosis of capillaria philippinensis by western blot using coproantigen and egg antigen

Capillaria philippinensis is a zoonotic nematode that causes severe diarrhoeal syndromes in humans. C. philippinensis coproantigen and egg antigen were fractionaled using SDS-PAGE. Several protein bands were detected in both antigens. Protein profile of coproantigen of C. philippinensis infected patient included wide range of bands ranging from 10 - 180 kD. Protein profile of egg antigen revealed few bands detected at 10, 34- 36.5, and 148 kD. Using Western blot, a variety of protein bands were recognized by the infected patient serum. When tested against coproantigen, it detected a wide range of antigenic proteins at different molecular weights [10, 14, 34-36.5, 48, 54, 62, 66, 86, 94, and 148 kD respectively]. None of these bands were detected in normal human feces. When tested against egg antigen, the infected patient serum detected only two faint antigenic bands at 62 and 66 kD. It is concluded that coproantigen is more convenient than egg antigen in diagnosis of capillariasis by WB

Incidence of chromosome abnormalities in the Sultanate of Oman

To evaluate the cytogenetic findings in Omani children referred for suspected chromosomal anomalies that caused a variety of clinical disorders. Secondly, to study the frequency of chromosomal abnormalities in these patients and to compare our results with those reported elsewhere. We performed chromosomal analysis on 1800 consecutive pediatric patients referred to the Cytogenetics section between June 1999 and May 2004 at Central Public Health Laboratories, Sultanate of Oman. Indication for referrals for exclusion of chromosomal rearrangements was multiple congenital anomalies, dysmorphic features, unclassified mental retardation, developmental delay, growth, and endocrine disorders. We carried out the lymphocyte culture according to standard methods. We found various types of chromosomal anomalies in 510 [28.3%] children and showed abnormal karyotypes in the form of trisomy 21 [391; 21.7%], trisomy 18 [32; 1.8%], trisomy 13 [20; 1.1%], sex chromosome aberrations [50; 2.8%] and other types of abnormalities [17; 0.95%]. There was a considerable phenotypic-cytogenetic heterogeneity. We found a high rate of chromosomal abnormalities in the present study, and we observed variations in the frequency of chromosomal aberrations reported by different investigators. The higher incidence of the chromosomal abnormalities demonstrates the importance of cytogenetic evaluation in patients with dysmorphic features and congenital anomalies. Our findings suggest that chromosome analysis is a useful tool in the investigation of children with genetic disorders of unknown origin for confirmation of clinical diagnosis and proper medical care followed by genetic counseling and management

Prevalence of sarcocystis in bovine meat and effect of cooking on its viability

Sarcocystis is one of the important parasites infecting bovine meat. Protection from infection needs supervised slaughtering and good cooking. Random samples of bovine meat and serum were collected from 100 cattle slaughtered in Assiut abattoir, inspected and examined macroscopically, microscopically and serologically for sarcocysts. The prevalence of infection by macroscopic examination was [2%] and microscopic examination was [64%], while the seroprevelance was [71%]. Infected meat samples were processed for different methods of cooking and the viability of Sarcocystis was estimated by antigen capture ELISA. The parasite lost its viability and antigenicity by heating at 66-68. The best safe methods for protection from infection were boiling for 10-20 minutes and grilling of small meat samples for 10 minutes and large samples for 20 minutes while roasting is risky when cooked as raredone

Effect of degree of conversion on the mechanical properties of different shades of composite resin restorative materials

The purpose of this investigation was to study the effect of the degree of conversion [DC] on the diametral tensile strength [DTS] and Vickers hardness [VH] of different shades [A[1], A[2] and A[4]] of Heliomolar [Microfilled] and Tetric Ceram [microhybrid] composite resin restorative materials. For each shade of composite, three experimental tests [DC, DTS and VH] were performed. The DC [%] was measured for the uncured and cured six shades of both types of composite using Fourier Transformation Infrared Spectroscopy. For DTS testing, disk-shaped specimens were prepared for each shade. The specimens were loaded to fracture in a Universal Testing Machine. Similar disk-shaped specimens were prepared to measure the composite's surface hardness using Vickers Micro-hardness Tester. The mean values of DC [%], DTS [MPa] and VH [kg/mm[2]] were calculated. The results were analyzed and compared using ANOVA and Least Significance Difference statistical tests. In addition, the interrelationship between DC, DTS and VH was investigated. The results showed that shade Al in both Heliomolar and Tetric Ceram showed the highest values of the DC, DTS and VH. On the other hand, shade A4 in both types exhibited the lowest values. There was a high positive correlation between all the studied parameters in both Heliomolar and Tetric Ceram composite resin