Mycotoxin residues in different chicken products by HPLC and their inactivation ‎using Gamma radiation

Mycotoxin residues were studied in different chicken products by HPLC and their inactivation using Gamma radiation. 120 differentchicken products were examined for the presence of mycotoxins (AFB1, AFB2, AFG1, AFG2, and OTA) using highly accurate and preciseHPLC-FLD assay. High recovery was achieved by purification of the sample extract using immunoaffinity columns (IAC). Derivatization ofAFs was carried out with a 0.005% aqueous solution of pyridine hydrobromide perbromide (PBPB) by utilizing a post-column LC pump.The incidence of mycotoxins in analyzed chicken products showed that the level of Afla B1, Afla B2, and Afla G2 were 10 % for each and ofAfla G1 and Ochra A were ranged from 10 to 16.7% for each. The results showed that the highest concentration of examined mycotoxinswas present in the liver as the liver is the harbor site of mycotoxin residues. The influence of different gamma irradiation rays (6, 8, and 10kGy) was studied on the reduction of the existed in examined chicken products. There is a positive connection between the elevation ofgamma irradiation dose used to the samples and the reduction level of total mycotoxins current in these samples, whereby, the mostreduction percentage of mycotoxins were achieved at 10 kGy; it reaches 19.6% for total mycotoxins, 27% for AF B1, 40.43% for AF B2,59.42% for AF G1, 92.15% for AF G2, and 73.44% for OTA.

Regeneration of Neural Networks in Immature Teeth with Non-Vital Pulp Following a Novel Regenerative Procedure

BACKGROUND AND OBJECTIVES: Recombinant amelogenin protein (RAP) was reported to induce soft-tissue regeneration in canine infected endodontically treated permanent teeth with open apices. To characterize identities of the cells found in the RAP regenerated tissues compared to authentic pulp by identifying: 1) stem cells by their expression of Sox2; 2) nerve fibers by distribution of the axonal marker peripherin; 3) axons by their expression of calcitonin gene–related peptide (CGRP); 4) the presence of astrocytes expressing glial fibrillary acidic proteins (GFAP).METHODS: A total of 240 open-apex root canals in dogs were used. After establishment of oral contamination to the pulp, the canals were cleaned, irrigated, and 120 canals filled with RAP, and the other 120 with calcium hydroxide.RESULTS: After 1, 3, and 6 months, teeth were recovered for immune-detection of protein markers associated with native pulp tissues. Regenerated pulp and apical papilla of RAP group revealed an abundance of stem cells showing intense immunoreactivity to Sox2 antibody, immunoreactivity of peripherin mainly in the A-fibers of the odontoblast layer and immunoreactivity to CGRP fibers in the central pulp region indicative of C-fibres. GFAP immunoreactivity was observed near the odontoblastic, cell-rich regions and throughout the regenerated pulp.CONCLUSIONS: RAP induces pulp regeneration following regenerative endodontic procedures with cells identity by gene expression demonstrating a distribution pattern similar to the authentic pulp innervation. A- and C-fibers, as well as GFAP specific to astrocytic differentiation, are recognized. The origin of the regenerated neural networks may be derived from the Sox2 identified stem cells within the apical papilla.

Radiological risk analysis of sediment from Kutubdia Island, Bangladesh due to natural and anthropogenic radionuclides

To assess the environmental radioactivity levels and hence to determine the population exposure in Kutubdia Island, Bangladesh the sediment samples were analyzed by using gamma ray spectrometry. In those sediment samples the average activity concentration of natural radionuclides [238]U, [232]Th and [40]K were found 15.39+/-1.67, 38.35+/-0.76 and 475.51+/-21.15 Bq/kg respectively. The activity concentration of [238]U and [232]Th were less than the world average. But the activity concentration of 40K was higher than the world average values. These results were used to calculate the radiological hazard parameters like radium equivalent activities [Ra[eq]], representative level index [I[gammar]]. Due to natural radionuclides in sediment, the effective annual outdoor dose in the study area was 0.07 mSv; which is within the accepted range of 0.07 mSv. The average value of radium equivalent activities [Ra[eq]] and representative level index [Igr] were found to be 128.03+/-12.08 Bq/Kg and 0.96+/-0.09 Bq/Kg which were greater than the world average. The anthropogenic radionuclide [137]Cs was also found in few samples. The average activity concentration of [137]Cs was 1.64+/-0.20 Bq/kg which is lower than the world average. The obtained experimental data of this research work would be useful to assess the population exposure from radionuclides in sediment as well as base line data of natural radioactivity in this island

HIV-1 (P24) Protein in Cervical Carcinomas.Tissue Samples [Histopathological and immunohistochemical study in Ethiopian Women]

HIV/AIDS remains the major developmental challenge for Ethiopia. Cancer cervix is the most prevalent in Ethiopian women where the HIV-1-infection increases the risk for the development of such cancers. This study was designed to identify immunohistochemically the HIV-1 directly in cervical cancer tissue samples independently from the HIV serology status of the patient. This is a retrospective study on formalin fixed and paraffin embedded cervical tissue at Pathology Unit Department of Medial Laboratory Sciences, college of Public Health and Medical Sciences Jimma University South-Western Ethiopia. The study covered 115 cervical tissues with invasive carcinoma; collected during the period of January 2008 till December 2010. The clinical data were received from the pathology biopsy request sheet. The slides were re-evaluated histopathologically and all specimens were studied immunohistochemically for identifying the HIV [P24] in the cancer cervix cells. HIV-l/p24 immunohistochemistry study of the cervical cancer tissues revealed positive immunostaining in 22 cases; 19.1%. The HIV-l/p24 was diffusely cytoplasmic with various degrees of staining intensities. Positive cytoplasmic staining was detected in the cervical epithelial cancer cells and also detected in the lymphocytes present in the intervening stroma. The identification of HIV-1 in the cytoplasm of the epithelial cervical cancer cells may contribute to cell cycle disruption or the virus itself may have a direct carcinogenic effect making it in someway for the development and progression of cancer cervix

Vitamin D Status of Infants in Northeastern Rural Bangladesh: Preliminary Observations and a Review of Potential Determinants.

Vitamin D deficiency is a global public-health concern, even in tropical regions where the risk of deficiency was previously assumed to be low due to cutaneous vitamin D synthesis stimulated by exposure to sun. Poor vitamin D status, indicated by low serum concentrations of 25-hydroxyvitamin D [25(OH)D], has been observed in South Asian populations. However, limited information is available on the vitamin D status of young infants in this region. Therefore, to gain preliminary insights into the vitamin D status of infants in rural Bangladesh, 25(OH)D was assessed in a group of community-sampled control participants in a pneumonia case-control study in rural Sylhet, Bangladesh (25°N) during the winter dry season (January-February). Among 29 infants aged 1-6 months, the mean 25(OH)D was 36.7 nmol/L [95% confidence interval (CI) 30.2-43.2]. The proportion of infants with vitamin D deficiency defined by 25(OH)D <25 nmol/L was 28% (95% CI 10-45), 59% (95% CI 40-78) had 25(OH)D<40 nmol/L, and all were below 80 nmol/L. From one to six months, there was a positive correlation between age and 25(OH)D (Spearman=0.65; p=0.0001). Within a larger group of 74 infants and toddlers aged 1-17 months (cases and controls recruited for the pneumonia study), young age was the only significant risk factor for vitamin D deficiency [25(OH)D <25 nmol/L]. Since conservative maternal clothing practices (i.e. veiling) and low frequency of intake of foods from animal source (other than fish) were common among the mothers of the participants, determinants of low maternal-infant 25(OH)D in Bangladesh deserve more detailed consideration in future studies. In conclusion, the vitamin D status in young infants in rural Sylhet, Bangladesh, was poorer than might be expected based on geographic considerations. The causes and consequences of low 25(OH)D in infancy and early childhood in this setting remain to be established.

prevalence and the pattern of HPV-16immunostaining in uterine cervical carcinomas in Ethiopian women: a pilot study

Cancer of the cervix uteri is the second most common cancer among women worldwide. The association of human papillomavirus [HPV] infection with cervical carcinogenesis is well documented. This is a pilot study aiming to studying the prevalence and the pattern of Human Papilloma Virus Type 16 [HPV 16] by immunostaining in the tissues of cervical carcinomas of Ethiopian women. 20 specimens of uterine cervical carcinomas were studied histopathologically and immunohistochemically for HPV 16. Histologically the specimens were classified as: Ten cases were Non Keratinized Squamous cell carcinoma [NKSCC], six cases were Keratinized Squamous Cell Carcinoma [KSCC] and four cases were Adenocarcinoma [ADC]. Immunohistochemistry study showed positivity in eleven cases [55%]; seven cases [35%] were non-keratinized squamous cell carcinoma; three cases [5%] were keratinized squamous cell carcinoma and one case [5%] belonged to the adenocarcinomas. This study reveals a significant detection of HPV in Ethiopian women by the use of advanced techniques such as Immunohistochemistry [IHC]. The data of this study suggested that the marked expression of the HPV 16 was in the less differentiated uterine cervix carcinomas

Tuberculous lymphadenitis in southwestern Ethiopia

Tuberculosis is a public health problem in Ethiopia and is one of the major causes of deaths. The present study is aiming at the clinic-pathological interpretation of tuberculosis cervical lymphadenopathy and to apply cheap methods to confirm the presence of Mycobacterium tuberculosis acid fast bacilli in the lymphoid tissues. Sixty cases with cervical lymphadenitis were included, clinical data was obtained from the medical records. Hematoxylin and Eosin staining was done to evaluate the morphological criteria of tuberculous cervical lymphadenitis also the specimens were studied for recognizing the Acid Fast Bacilli. In our study the positive presence of the Acid Fast Bacilli showed a significant statistical associations with the presence of pulmonary tuberculosis; caseation necrosis and HIV serologically positive [p=0.00001, 0.0082 and 0.0272 respectively]; meanwhile there was no significant associations with the age, sex of patient or the family history of tuberculosis [p=0.2011, 0.2330 and 0.2276 respectively]. We conclude that the Iight microscopic assessment is a useful screening method to diagnose tuberculosis in cases of cervical lymphadenitis; moreover, the efficacy of diagnosis was improved when combined with identifying the infecting organism. The procedure in the present study is a cheap reliable method that can he useful in the diagnosis of tuberculosis lymphadenitis and also it can help] in the proper therapeutic approach

Students' portfolio: a new trend to assess the fourth year nurse students' mastery of the administrative skills

This study was conducted at the Faculty of Nursing in Assiut University to apply students' portfolio as a new trend to assess the fourth year student's mastery of the administrative skills. The study sample consisted of 60 students classified as thirty experimental group and thirty control group. Data collected through students' assessment by applying students' portfolio as assessment tool. Data collection took about two months. The results revealed that using of students' portfolios leads to enhancement of student's personal and professional level. At the area of administrative skills they become able to achieve assignment sheet accurately, they become excellent in performing daily shift report, gain ability to completion of patient cards effectively, identify patient needs, and describe the proper nursing care according to priorities. They are able to use proper documentations at different types of hospital departments, while the control group improved at the assignment sheet, daily shift report and patient cards to some extent and did not have new skills as the experimental groups

Comparison of BMI-for-age in adolescent girls in 3 countries of the Eastern Mediterranean Region

International comparisons of adolescent overweight and obesity are hampered by the lack of a single agreed measurement reference. We compared 3 BMI- for- age references on samples of adolescent girls from Egypt, Kuwait and Lebanon. Overweight and obesity was highest in Kuwait and lowest in Lebanon. Performance of the 3 standards differed only slightly although one was particularly applicable in country- to- country comparisons

Assessment of ground reaction force components in stroke patients

The purpose of this study was to evaluate the ground reaction force components in stroke patients [mild and moderate spasticity] and to compare them with normal subjects' parameters. Fifteen normal subjects and thirty stroke patients were participated in this study. Stroke patients were assigned into two equal groups, group I with mild spasticity and group II with moderate spasticity. All components of ground reaction force [vertical and horizontal [anteroposterior and lateral]] were calculated both in normal subjects and stroke patients. Force platform with a computer system were used to calculate ground reaction force components. Results of the study showed varied significant reduction of ground reaction force in all parameters in both groups [I and II] of stroke patients compared with normal subjects. All ground reaction force parameters were significantly higher in patients with mild spasticity, compared to moderate once. So, assessment of ground reaction force should be considered as a useful evaluating tool for kinetic gait analysis of patients. It also helps in detecting the prognosis of stroke patients, by comparing the ground reaction force parameters of those patients with normal parameters

E-cadherin in relation with the proliferating cell nuclear antigen of the bilharzia associated and non-associated urinary bladder carcinoma

Background: e-cadherin is a trans-membrane glycoprotein that plays a critical role in many aspects of cell adhesion as well as establishment and maintenance of epithelial cell polarity. Loss of the adhesive function of E-cadherin seems to promote invasive and metastatic properties of neoplastic cells

Objectives: the present study is a retrospective study aiming to evaluate the loss of E-cadherin immunohistochemical expression in relation with the proliferating cell nuclear antigen expression of the bilharzia associated and non-associated bladder carcinoma

Methods: forty TUR-bladder carcinoma sections immunohistochemically stained with E-cadherin antibody were microscopically interpreted and results were correlated to the established prognostic factors, including proliferating index as assessed by the proliferating cell nuclear antigen [PCNA] immunostaining, histopathological types, tumor cell grade, tumor invasiveness and bilharzia association

Results: histopathologically, 63% were transitional cell carcinoma, 33% were squamous cell carcinoma and 5% were adenocarcinoma. Loss of E-cadherin expression had a significant association with high PCNA index [p<0.01], the tumor grade [p<0.002], tumor invasiveness [p<0.001], and bilharzias- associated bladder cancer [p<0.04]. There was no statistically significant association between loss or decrease of Ecadherin expression and histopathological typing of urinary bladder carcinoma [p=0.094]

Conclusion: loss of E-cadherin provides an additional aid in assessment of prognosis and planning of therapy of patients with urinary bladder carcinoma as it indicates the potentiality for metastasis by its significant association with high proliferating cell nuclear antigen index, high tumor grade and tumor invasiveness. Moreover, immunohistochemical interpretation of E-cadherin altered adhesive function is a useful histological prognostic marker in bilharzia associated urinary bladder carcinoma

Demonstration of species-specific and cross-reactive components of hydatid cyst fluid antigens

ELISA-hydatid cyst fluid antigen [HCF-Ag-ELISA] and conventional echinococcosis IHAT were assessed for cystic hydatid disease [CHD] confirmed by HCF-Ag immunoblotting assay. The sensitivity of the tests was 94.4% and 83.3% for HCF-Ag-ELISA and IHA, respectively. HCF-Ag-ELISA showed some cross reactions in tumor cases [5.5%], but no cross reaction was observed in rheumatoid arthritis patients. IHA showed 100% specificity. To confirm this data, SDS- PAGE immunoblotting using HCF-Ag was applied. Echinococcus specific reactions were reported with 44 Kda, 34 Kda, 29 Kda and 8 Kda HCF-Ag resolved bands. A cross reaction was found with 27 Kda, 21 Kda, 16 Kda and 13 Kda bands in tumor patients. Moreover, a cross reaction was found with 200 Kda, 175 Kda, 62 Kda, 52 Kda and 40 Kda in serological anti-schistosoma antibodies positive cases. So, using specific HCF-Ag immunoblotting provided 100% sensitivity and specificity in CHD

Protective effect of casein and/or ascorbic acid some metabolic and pathological changes induced by malathion insecticide in rats

Seventy five weanling male albino rats were divided into 5 separate groups each of 15 rats; G I was supplemented with basal diet only [control -ve]. Rats of other groups G II, III, IV and V were intoxicated by malathion in a dose of 137.5 mg/kg body weight [1/10 of non lethal effected dose] for 30 days, while casein and ascorbic acid were given either alone or in combination for 45 [G III, GIV and GV] days. Five rats from each group were sacrificed at 15, 30 and 45 days post-treatment. Serum samples and tissue specimens were subjected for biochemical analysis and histopathological studies respectively. Serum biochemical analysis revealed that malathion suppressed SChE and elevated ALT, AST und ALP activities, caused hyperglycemia and affected lipid profile by increasing triacylglycerol, cholesterol and total lipids concentrations while supplementation with casein and ascorbic acid partially reduced the former metabolic changes. Histopathological examination revealed hemorrhages, severe necrobiotic changes in the internal organs of rats treated with malathion insecticide only, moderate changes were detected in rats treated with casein or ascorbic acid and mild lesions were noticed in rats treated with a combination of casein and ascorbic acid. It was concluded that chronic toxicity incited by malathion insecticides in a rat as a laboratory model was particularly reduced on using ascorbic acid as a natural antioxidant and/or casein as a dietary protein in farm animal ration

Selective screening for biotinidase deficiency

Biotinidase deficiency is characterized by neurological and cutaneous manifestations that can be prevented or ameliorated by oral biotin therapy. The present work aims to establish the prevalence of biotinidase deficiency in a targeted group of infants and children presenting with neurological and cutaneous problems or isolated cutaneous symptoms, during a two year period. We measured biotinidase activity and obtained medical histories and examinations of probands, as well as of available parents and siblings. Among 13 children presenting with neurological symptoms associated with intractable seborrheic dermatitis and/or alopecia, we identified 6 patients with profound biotinidase deficiency [activity<10% of mean normal activity] and one patient with partial biotinidase deficiency [activity between l0%-30% of mean normal activity]. Among 40 infants presenting with isolated intractable seborrheic dermatitis, we identified one infant with profound biotinidase deficiency and another with partial biotinidase deficiency. Normal healthy controls had biotinidase activities within normal ranges, Biotinidase activity in 5 parents and 3 siblings was intermediate between those of probands and those of normal individuals. We identified one asymptomatic sibling with biotinidase activity in the partial activity range. Among the most common neurological findings on presentation were developmental delay or regression in 66.6%, hypotonia in 66.6%, seizures in 55.5%, neurosensory hearing loss in 33.3%, ataxia in 22.2% and optic atrophy in 22.2% of patients. One patient presented with a spontaneous episode of metabolic acidosis. Age of onset was between 1 and 3 months of age in 66.6% of patients. Two patients presented later than the usual age of onset. There was no clear relationship between age of onset and either severity or type of deficiency. All patients showed resolution of skin problems and marked improvement in neurological symptoms on oral biotin treatment. Detection of 9 cases of biotinidase deficiency during a two year period at a single metabolic unit indicates that biotinidase deficiency is not rare in Egypt. We suggest that biotinidase deficiency be considered in all children with neurological symptoms particularly those associated with cutaneous manifestations. Biotinidase deficiency should be considered in the differential diagnosis of intractable seborrheic dermatitis. The high incidence of biotinidase deficiency, the low cost of screening test, and the inexpensive therapy cost increase the importance of neonatal screening for biotinidase deficiency in Egypt. This would prevent permanent neurological damage or death in future children with biotinidase deficiency

effect of theophylline on serum erythropietin in premature neonates and older children

To study the effect of theophylline on erythropoietin, 4 groups were included in this work: group I [theophylline treated prematures], group II [theophylline untreated prematures for comparison], group III [theophylline treated children] and group IV [theophylline untreated children] for comparison. For all subjects, serum level of erythropoietin, haemoglobin concentration, red cell count, haematocrit value and serum level of theophylline [for treated subjects only] were performed at the beginning and at the end of the study. The results obtained showed a significant elevation in erythropoietin, Hb, RBCs and haematocrit values in group I as compared with group II as well as a significant decrease in erythropoietin level, Hb, RBCs and haematocrit value in group III as compared with group IV. We concluded that there is a discrepancy in the effect of theophylline therapy on serum erythropoietin level between prematures and older children. This may be due to the altered tissue oxygenation seen in apnea of prematurity which may have a more potent stimulatory effect on erythropoietin production than does the depressant effect of theophylline in this population. Also, the effect of theophylline on erythropoietin production may change by age and thus may differ between prematures and older children

Saudi experience with classic homocystinuria

Classic homocystinuria is an autosomal recessive disorder due to cystathionine P-synthase deficiency. The clinical, radiological and neurophysiological findings of classic homocystinuria diagnosed at King Faisal Specialist Hospital and Research Centre [KFSH and RC] are presented in this report. Patients and Methods: Twenty-four patients [15 females and 9 males] were referred to KFSH and RC for work-up of mental retardation, seizures, thrombo-embolic episodes and dislocation of the ocular lenses. The common clinical findings included ectopia lentis [20 patients, skeletal system involvement [18 patients], vascular system involvement [9 patients], and mental retardation [all patients to varying degrees]. Unusual findings consisted of a patient who developed severe lower gastrointestinal bleeding, a patient with insulin-dependent diabetes mellitus, probably due to vasculopathy, and another having severe bronchiectasis, which may have been due to fibril] in disruption, and required the resection of a lobe of the lung. The parents of 21 patients were first-degree relatives, and 19 patients had one or more family members affected by the same disease. All patients had markedly elevated plasma levels of methionine. Cystathionine synthase activity in the fibroblast was measured in 25% of the patients and was deficient. Only four patients responded to pyridoxine and their methionine level decreased to almost normal range. The aim of this study was to increase the awareness of this disease in the scientific and medical community, in particular in the general pediatrician working in Saudi Arabia who first encounters the clinical manifestations of the disease. Early detection through tandem mass spectrometry of blood spot screening and treatment are important, and may prevent the major complications of this disease

Biochemical, nutritional and pharmacological evaluation of the antiarthritic activity of some Egyptian plants

The antiarthritic activity of some bioactive extracts of fenugreek seeds and Liquorice roots and the whole coriander fruit powder were tested in rats in which adjuvant arthitis was induced in comparison with two synthetic anti-inflammatory drugs. The results of the tested natural agents showed a significant inhibition of the inflammed regions with different degrees. The highest inhibition was due to the petroleum ether extract of fenugreek [67%] followed by the aqueous methanolic extract of liquorice [65%]. Biochemically administration of the natural agents or reference drugs to arthritic rats produced pronounced improvement of the level of certain biochemical parameters reflecting the arthritic state in rate; such as erythrocyte sedimentation rate and serum seromucoids, copper, fibrinogen, albumin and albumin: globulin ratio. Nutritionally arthritic rats lost weight significantly if compared with control normal ones. Administration of urbason retard to arthritic rats produced a significant reduction in body weight and food efficiency ratio if compared to control arthritic, while aqueous methanolic extract of fenugreek produced a significant increase in body weight. No significant changes in total food intake were noticed among the different groups receiving the tested agents

Effect of wheat flour and yeast on balady bread characteristics

Three wheat flour varieties [Giza 157, Sakha 8 and Sakha 69] and 3 different sources of yeast were used for the production of Balady bread. There were slight differences in the main constituents of wheat flour varieties. Rheological properties [as measured by farinograph and extensograph] indicated that the strength of flour dough changed in a decreasing order as Sakha 69> Sakha 8> Giza 157. Sensory evaluation of the produced bread revealed a higher score for dry yeast [0.5%] followed by compressed yeast [0.75%] then Soltani starter [25%]. The results, also, showed that the staling of bread loaves was significantly affected by wheat flour variety and type and level of yeast added. Slight differences in the chemical composition of the produced bread were also noticed

Evaluation of bone strength and scanning electron microscopic [SEM] examination of the interface between dentin adhesive systems, glass ionomer cement and sclerotic dentin

The purpose of this study was to evaluate the bond strength of two adhesive systems to sclerotic and normal dentin, as Compared to glass ionomer cement restoration material. The microstructure of the interface between glass ionomer cement, the adhesive systems / dentin was examined using scanning electron microscope. Two dentin bonding systems were used in this study Scotch bond Multi-Purpose [fourth generation] and Syntac [third generation], with their composite resin [Z[100] and Helimolar]. Glass ionomer cement restorative material [GIC] was also used. Twenty-one Caries freshly extracted human premolars were collected and stored in distilleds water. Another twenty-one caries-free human premolars showing severe occlusal attrition, were collected from patients over 60 years. The teeth were selected according to the criteria of dentin sclerosis scale described by Heyman and Bayne in 1993 [Table II]. The occlusal surfaces of the teeth were ground flat on a water-cooled abrasive wheel to expose dentin for preparation of the specimens for shear bond strength test. The 42 teeth were divided into two main groups, Group [I], normal dentin [21 teeth], and Group [II], sclerotic dentin [21 teeth]. Each group was further subdivided into three subgroups [a, b and c]. Group I[a] and II[a] [Scotchbond Multi-Purpose with Z[100]] - Group I[b] and II[b] [Syntac and Helimoler], Group I[c] and II[c] [Glass ionomer cement- Fuji II]. The shear bond strength was determined in a Universal Testing Machine with cross head speed of 1 cm/minute. The fractured specimens were cut longitudinally and examined using scanning electron microscope [SEM]. From the obtained results, the following could be concluded: 1] It is increasingly important that Clinicians should recognize differences in dentin composition before planning restorations that depend on the use of dentin bonding systems. 2] By SEM examination, the clinical criteria of sclerosis [glassy appearance of dentin] was confirmed and the dentinal tubules were partly or completely obliterated by mineral crystals,providing a uniform refractive index of the dentinal tubules. 3] Dentin sclerosis significantly affected the bond strength of the two dentin bonding system used in this study. However, dentin adhesive system that recommended a total etch pre-treatment of dentin, i.e. uses an etchent and a primer, offers more reliable bonding to both normal and sclerotic dentin. This was clearly observed in SEM, where the Scotchbond MP shows more resin tags development with both normal and sclerotic dentin. 4] Although glass ionomer cement showed a higher bond strength to sclerotic dentin, these bond strength values were significantly lower than those of adhesive bonding systems. 5] Further researches are needed to develop adhesive systems that bond equally well to various kinds of dentin substrate. Also, extending the application time of the etchent of existing dentin adhesive systems or the use of more aggressive acids may be of benefit