Seven stains were studied to determine the best color and contrast for staining the developmental stages of free living pathogenic Acanthamoeba and Naegleria species. The acid-fast bacilli stain (AFB) produced a blue color without contrast; trichrome-eosin and modified Field's showed various color contrasts; Giemsa, iron-hematoxylin, modified AFB and Gram produced only one color which distinguished the nucleus, nucleolus, cytoplasm, food- and water-vacuoles. The motile organs (acanthopodia, pseudopodia, lobopodia and flagella) were also clearly differentiated but produced a similar color as the cytoplasm. These motile organelles were first induced by incubating at 37 degrees C for at least 15 minutes and then fixing with methanol in order to preserve the protruding morphology prior to staining. The trichrome-eosin and iron-hematoxylin stains showed good color contrast for detecting all three stages, the trophozoite, cyst and flagellate; Giemsa and Gram stained the trophozoite and flagellate stages; the modified Field's and modified AFB stains stained only the trophozoite stage. Depending on the purpose, all these stains (except the AFB stain) can be used to identify the developmental stages of Acanthamoeba and Naegleria for clinical, epidemiological or public health use.
Matched MeSH terms: Staining and Labeling/methods*
Routine diagnosis of intestinal microsporidiosis in clinical diagnostic laboratories relies mostly on detection of microsporidial spores via special staining and microscopic techniques. This paper describes the comparative evaluation of Calcofluor White M2R method, with modified Gram-chromotrope Kinyoun method as the reference standard. One hundred and six stool samples were examined for the presence of microsporidial spores. Sensitivity, specificity, positive and negative predictive values of the Calcofluor White M2R method compared to the reference technique were 95.2%, 4.3%, 78.2% and 20.0%, respectively. The positive predictive value (PPV) was 78.2% and the negative predictive value (NPV) was 20.0%. Despite low specificity of the CFW method due to its ability to stain chitinous wall of microorganisms, the presence of distinct deep-blue horizontal or equitorial stripes in microsporidial spores in modified Gram-chromotrope Kinyoun would likely reduce the false positive results obtained in the Calcofluor White M2R. Hence, the simultaneous use of these two methods would give better performance and accuracy for the detection of microsporidial spores in patients with intestinal microsporidiosis.
Decalcified permanent teeth were sectioned and stained with Van Gieson and Gomori trichome dyes. Sections dyed with the Van Gieson dye did not produce any zones in dentine but with the Gomori trichome dye, four different zones of dentine were produced. Zone 1 begins at the predentine-dentine junction while zone 4 ends at the enamel - dentine junction. In zone 1, the intertubular dentine was stained clearly while in zone 3 intense staining of the peritubular dentine was observed. The result of this study supports the previous findings reported by other workers that the formation of intertubular dentine takes place in zone 1 while peritubular dentine occurs in zone 3.
Biofilm formation can lead to various consequences in the food processing line such as contamination and equipment breakdowns. Since formation of biofilm can occur in various conditions; this study was carried out using L. monocytogenes ATCC 19112 and its biofilm formation ability tested under various concentrations of sodium chloride and temperatures. Cultures of L. monocytogenes ATCC 19112 were placed in 96-well microtitre plate containing concentration of sodium chloride from 1-10% (w/v) and incubated at different temperature of 4 °C, 30 °C and 45 °C for up to 60 h. Absorbance reading of crystal violet staining showed the density of biofilm formed in the 96-well microtitre plates was significantly higher when incubated in 4 °C. The formation of biofilm also occurs at a faster rate at 4 °C and higher optical density (OD 570 nm) was observed at 45 °C. This shows that storage under formation of biofilm that may lead to a higher contamination along the processing line in the food industry. Formation of biofilm was found to be more dependent on temperature compared to sodium chloride stress.
Most methods used in double esterase cytochemistry for the diagnosis and classification of acute myeloid leukaemias require double incubation and staining, using separate coupling reagents. We evaluated a method by Swirsky on our normal and abnormal blood and bone marrow smears where only a single incubation and the use of a single coupling reagent is required. Its short incubation period and its strong positive reaction for butyrate esterase in demonstrating cells of monocytic lineage gives it an advantage over the conventional double incubation technique.
Objectives: The aim of the study is to evaluate the effect of the time and instant coffee solution on the color stability of three types of composite resin based veneer systems. Materials and Methods: 24 composite resin veneer samples were selected and divided into three groups: two groups of prefabricated veneers (Edelweiss, Ultradent Inc™ (EDL) and Componeer, Coltène/ Whaledent AGTM (CMP)) and one group of laboratory made (Nexco, Ivoclar Vivadent (NEX)) veneer system were tested (n=8). Specimens were prepared and stored in staining solution (instant coffee) and assessed color changes with Minolta spectrophotometer every three days for a period of 27 days, after which color differences (ΔE*) were calculated. Data collection and analysis was done using one-way ANOVA and Student’s t-test (α=0.05). Results: One-way ANOVA revealed a significant difference in color stability between the two veneer systems. NEX group veneer system exhibited the highest color stability (ΔE*= 0.73 ± 0.5) as compared to prefabricated veneer groups (EDL 10.07 ± 5.15, CMP 7.41 ± 4.64) with p value
Culture expanded chondrocytes isolated from non-load bearing region of osteoarthritic (OA) joint has been used to construct tissue engineered cartilage for treatment purposes. The aim of the study was to compare the histological properties of the cartilage tissue and morphological properties of the chondrocytes isolated from less and severely affected OA knee. Human articular cartilage was obtained as redundant tissue from consented patients with late-stage OA undergoing total knee replacement surgery at Universiti Kebangsaan Malaysia Medical Centre (UKMMC). Articular cartilage was graded according to Dougados and Osteoarthritis Research Society International (OARSI) classification. Articular cartilage was classified into less affected (LA; Grade 0-1) and severely affected (SA; Grade 2-3). Cartilage tissue from less and severely affected region was stained with Safranin O staining. Isolated chondrocytes from each group were cultured until passage 4 (P4). Their growth patterns, cell areas, and circularity were compared. LA-cartilage tissue shows uniform spread of safranin O staining indicating intact extracellular matrix (ECM) component. However, SA-cartilage shows significant reduction and unstable staining due to its degraded ECM. LA-chondrocytes showed an aggregated growth compared to SA-chondrocyte that remains monolayer. Moreover, LA-chondrocytes have significantly higher cell area with wider spreading at passage 0 and 4 compared to SA-chondrocytes. It was also found that chondrocyte circularity increased with passage, and circularity of LAchondrocytes was significantly higher than that of the SA-chondrocytes at passage 3. This study demonstrated the considerable difference in the cellular properties for less and severely affected chondrocytes and implication of these differences in cell-based therapy needed to be explored.
Religious fasting is an act of refraining oneself from eating and drinking beginning at dawn until sunset. The changes in meal time and long period of meal constraint may influence the tear quality and ocular surface. The purpose of this study was to investigate the effect of daily religious fasting on tear film characteristics and ocular surface integrity. This is a prospective study involving 29 eyes from 29 healthy participants. The tear film characteristics were assessed by measuring the non-invasive tear break-up time (NITBUT), tear meniscus height (TMH), total tear secretion, and
fluorescein ocular surface staining method was used to determine the ocular surface integrity. The measurements were performed in the morning (8.00 to 10.00 a.m.) and evening (4.00 to 6.00 p.m.) during each non-fasting and fasting period. The results showed no statistically significant difference noted for all parameters measured in the morning when comparison was made between non-fasting and fasting periods. Conversely, in the evening, NITBUT value was significantly lower during fasting period, (p = 0.001), but, TMH, total tear secretion and ocular surface staining revealed no significant differences between non-fasting and fasting periods. Our study revealed
that daily religious fasting only significantly reduced the NITBUT value in the evening which possibly due to dehydration; however, it did not affect TMH, total tear secretion and ocular surface integrity. The absence of fluid loading at pre-dawn meal could be the reason of non-noticeable differences noted in the morning
Objectives: The objectives of the study were to assess: i) the staining susceptibility of composite resins, ii) the ability of whitening toothpastes in removing stains from composite resins.
Materials and Methods: Thirty specimens from each composite resins: Filtek Z350 (3M ESPE), Filtek Z250 (3M ESPE) and Beautifil (Shofu Inc.) were fabricated. After polishing, specimens were immersed in coffee for 3 days. Specimens were then brushed twice a day for 2 weeks using Colgate Total (Colgate-Palmolive, control group), Colgate Advanced Whitening (Colgate- Palmolive, test group) and Darlie All Shiny White (Hawley & Hazel Chemical Co., test group). Colour changes (?E*) were measured using Spectrophotometer at baseline, after coffee immersion and after brushing. Results were statistically analyzed using one way ANOVA and Tukey’s test.
Results: There was significant difference in terms of colour changes for Filtek Z350, Filtek Z250 and Beautifil after coffee immersion (P0.05).
Conclusions: Filtek Z350 was able to resist staining by coffee better than Filtek Z250 and Beautifil. The whitening toothpastes did not offer added advantage in terms of ability to remove stains compared to ordinary toothpaste.
Phosphophoryn, a higWyphosphorylated protein, is the most abundant protein among the non-collagenous protein of dentine. The staining of phosphophoryn can be done by using the silver colloid staining. In this paper, the staining effect of the silver colloid stain on both non-sclerotic and sclerotic dentine was investigated. Eight teeth from donors aged 14, 17, 22, 34, 55, 57, 60 and 65 were used for this experiment. The younger teeth were used to demonstrate normal root dentine while the older age teeth were used to demonstrate sclerotic root dentine at the apical region of the root. There was no staining of the normal root dentine as compared to sclerotic dentine when the silver colloid staining was used.
Establishing time of death has been extensively studied for the last 30 years. Parameters that have been studied included body temperature, biochemistry of rigor mortis, putrefactive changes and entomology. Despite an extensive study in these parameters it was found that all of the parameters were very much dependent on external factors like changes in surrounding temperature and activities done prior to death. To solve this problem, we decided to monitor the mechanism that occurs during death. Until now, various researches have found that during the early stage of death, heart and perfusion to the cells will stop. This will cause the cells to start the death process. The death of the cell will occurs either through apoptosis or necrosis. During apoptosis the cells will switch on and off a few proteins in a sequence. Based on this understanding, a study was conducted to determine if area ratio of apoptosis: necrosis and apoptotic p53 and Bcl-2 markers can be used as a reliable postmortem interval marker (PMI). Sampling of the study had involved 100 dead human skins with a known PMI. All samples were obtained from forensic unit of Hospital Kuala Lumpur (UFHKL). Ratio of apoptosis: necrosis areas were determined using hematoxilin and eosin staining while apoptosis p53 and Bcl-2 markers were done using an apoptosis kit. All staining were then indexed and plotted against PMI data obtained from UFHKL. Results indicated that there were no significant correlations between ratio of apoptosis: necrosis area against PMI (p = 0.144). Whereas for both apoptotic markers p53 and Bcl-2 PMI had shown a significant correlation (p < 0.000 for both results). In conclusion, we suggest that p53 and Bcl-2 parameters should be studied further since it is very likely that it could be a good indicator for PMI.
A 47-year-old lady, presented with progressive proptosis of left eye with deterioration of vision. She had a history of left solitary fibrous tumour and had undergone left frontal craniotomy and orbitotomy in 2004. Surveillance Magnetic resonance imaging (MRI) six years later showed tumour recurrence with intracranial extension. However, she did not follow-up and only presented again 3 years, later. Tumour resection and left exenteration was performed. Histology showed ‘patternless’ pattern of neoplastic cells, and CD34 staining was diffusely positive. Diagnosis of recurrent solitary fibrous tumour with intracranial extension was made.
A study was carried out to investigate whether smoking had any effect on the Langerhans cells in the oral mucosa, which might throw light onto the mechanism of malignant transformation of some keratotic lesions in the oral cavity. Thirty-two cases of keratotic lesions from biopsy specimens of smokers and non-smokers were studied. Langerhans cells were identified by immuno cytochemical staining for 5100 proteins and their densities quantified. Smokers were associated with a significant reduction in the Langerhans cell population compared to non-smokers. The mean values of Langellans cell density in light smokers and heavy smokers were 2 2 2 28.64/mm and 33.421mm respectively compared to 66.51/mm in non- smokers. There was a dose-response relation between the number of cigarettes smoked daily and the effect on cell counts. These findings of a local immunological effect of smoking on oral epithelium may explain the means by which cigarette smoking contributes to the development of oral cancer.