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Objective:To investigate the effect of 1 064-nm Q-switched Nd:YAG laser at different energy settings on cell viability, protease activity and structures of Malassezia furfur. Methods:Cultured standard strains of Malassezia furfur were divided into several groups to be irradiated with 1 064-nm Q-switched Nd:YAG laser at different energies of 0 (control group) , 500, 600, 700, 800 and 900 mJ, respectively. Then, fungal suspensions in the above groups were inoculated onto the Leeming & Notman medium separately. After 7-day culture, the diameter and number of colonies were measured to evaluate the fungal cell viability, the protease activity was measured by using the whole-milk plate medium, and the ultrastructure of Malassezia furfur in each group was observed by transmission electron microscopy. One-way analysis of variance was used for comparisons among multiple groups, least significant difference- t test for multiple comparisons, and Pearson correlation analysis for analyzing correlations of laser energy with colony diameter, number and protease activity. Results:The colony diameter and number both significantly differed among the control group, 500-, 600-, 700-, 800- and 900-mJ groups (colony diameter: 4.05 ± 0.69, 3.76 ± 0.51, 3.28 ± 0.41, 3.09 ± 0.72, 2.54 ± 0.64 and 2.43 ± 0.41 mm, respectively; colony number: 4 787 ± 597, 4 287 ± 761, 1 879 ± 275, 1 082 ± 248 and 209 ± 42, 72 ± 31 colony-forming units, respectively; F = 14.83, 231.85, respectively, both P < 0.05) , and were significantly decreased in the 600-, 700-, 800- and 900-mJ groups compared with the control group (all P < 0.05) . The laser energy was negatively correlated with the colony diameter and number ( r = -0.67, -0.91, respectively, both P < 0.05) . The protease activity significantly differed among the control group, 500-, 700- and 900-mJ groups ( F = 346.60, P < 0.05) , and was significantly lower in the 700- and 900-mJ groups than in the control group (both P < 0.05) . There was a negative correlation between the laser energy and protease activity ( r = -0.94, P < 0.05) . Transmission electron microscopy showed intact fungal structures in the control group, relatively intact fungal structures in the 500-mJ group, and obviously damaged fungal structures in the 600- to 900-mJ groups, and the greater the laser energy, the more severely the fungal structures were damaged. Conclusion:The 1 064-nm Q-switched Nd:YAG laser could affect the cell viability of and protease activity in Malassezia furfur, and damage its structures.
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SUMMARY: Nucleolus Organizer Regions (NORs) are defined as nucleolar components containing argyrophilic proteins selectively stained by silver methods (AgNORs). Several investigations have shown the AgNOR quantity and area represent a valuable parameter of cell kinetics, since they reflect the level of activity and cellular proliferation. This article addresses an evaluation of the functional activity and relation between days of pregnancy and proliferative capacity of trophoblastic mononucleate and binucleate cells from bovine placentomes. Both the number and size of AgNORs were determined in different phases of gestation by silver nitrate staining in conventional histological slides. The results showed a significant increase (from 1 to 12 AgNORs) in the number of AgNORS per trophoblastic mononucleate cell in the 3rd trimester, with predominance of 4-6 AgNORs/cell. In the 1st and 2nd trimesters, the number ranged between 1 and 9 AgNORs/cell, with predominance of 1-3 AgNORs. No significant differences were observed between the 2nd and 3rd trimesters, but in the first, in binucleate cells (19-27 and 10-18 AgNORs/cell, respectively) - this number was higher than the one registered in trophoblastic mononucleate cells in the same period. Thus, AgNORs can be used as markers of the proliferative placental cell cycle and established a relation between number of AgNORs and days of gestation. This relation can be used for diagnoses and prognoses of several placental pathologies, including pregnancy losses from manipulated embryos.
RESUMEN: Las Regiones Organizadoras de Nucléolos (NOR) se definen como componentes nucleolares que contienen proteínas argirofílicas teñidas selectivamente por métodos de plata (AgNOR). Varias investigaciones han demostrado que la cantidad y el área de AgNOR representan un parámetro importante de la cinética celular, ya que reflejan el nivel de actividad y proliferación celular. Este trabajo analiza la actividad funcional y la relación entre los días de preñez y la capacidad proliferativa de las células trofoblásticas mononucleadas y binucleadas de placentomas bovinos. Tanto el número como el tamaño de los AgNOR se determinaron en diferentes fases de la gestación mediante tinción con nitrato de plata en portaobjetos histológicos convencionales. Los resultados mostraron un aumento significativo (de 1 a 12 AgNOR) en el número de AgNORS por célula mononucleada trofoblástica en el tercer trimestre, con predominio de 4-6 AgNOR / célula. En el primer y segundo trimestre, el número osciló entre 1 y 9 AgNOR / célula, con predominio de 1-3 AgNOR. No se observaron diferencias significativas entre el 2do y 3er trimester; en el primer trimestre, en células binucleadas (19-27 y 10-18 AgNORs / célula, respectivamente) - este número fue superior a la cantidad registrada en células mononucleadas trofoblásticas en el mismo período. Por tanto, los AgNOR se pueden utilizar como marcadores del ciclo celular placentario proliferativo y se establece una relación entre el número de AgNOR y los días de gestación. Esta relación puede ser útil en el diagnóstico y pronóstico de varias patologías placentarias, incluidas las pérdidas de preñeces de embriones manipulados.
Subject(s)
Animals , Female , Pregnancy , Cattle , Placenta/metabolism , Cell Proliferation , Nucleolus Organizer Region/metabolismABSTRACT
Objective To observe the ameloblast morphology and ultrastructure changes of dental fluorosis in rats.Methods Forty SD rats were divided into experimental group and control group (20 rats in each group) by body weight using random number table method.Rats in experimental group were given drinking water with 50 mg/L fluoride to establish dental fluorosis model,and rats in control group were given drinking water without fluoride.All rats were killed at the 56th day,then ameloblast morphology and ultrastructure were observed by means of HE staining and transmission electron microscopy (TEM) at secretory,transition,maturation and post-maturation stages.Results Rats in experimental group showed typical symptoms of dental fluorosis,and lower incisors presented brown and white stripes on enamel surface,chalk color patches and other typical dental fluorosis changes,rats in control group no abnormality.HE staining results showed that differences were not observed between the two groups at the secretory and transformation stages,and few distortions and interstitial space widened were found in the experimental group at maturation and post-maturation stages.TEM displayed ultrastructure changes of ameloblasts,and no differences were observed between the two groups at secretory and transformation stages.Apoptosis was observed in some ameloblasts at the maturation stage in the experimental group,such as rough endoplasmic reticulum expansion,swelling,some ribosome particles exfoliating from endoplasmic reticulum,mitochondrial swelling and disappearance of crista,some nuclear membrane broken down,chromatin condensation and karyolysis.At post-maturation stage,intercellular space of the experimental group was wider than that of the control group.Conclusions Morphological and ultrastructure damage of ameloblasts may have occurred at the maturation stage in the process of dental fluorosis.Ameloblasts may be more sensitive to fluoride in dental enamel formation at maturation stage.
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BACKGROUND:Placental mesenchymal stem cel s with rich sources are similar to bone marrow mesenchymal stem cel s in terms of morphology, surface markers and differentiation potential, which are one of ideal mesenchymal stem cel s in human body. However, there are few studies addressing the ultrastructure and phagocytotic function of human placental mesenchymal stem cel s and its physiological role in the the placenta has been little explored. OBJECTIVE:To investigate the ultrastrcture and phagocytotic function of placental mesenchymal stem cel s. METHODS:Placental mesenchymal stem cel s obtained from five placentae of normal pregnancy were cultured in vitro and observed for ultrastructure under transmission electron microscope. The fluorescent beads were added in the supernatant for 3 hours, and then the phagocytosis of placental mesenchymal stem cel s was evaluated by flow cytometry. RESULTS AND CONCLUSION:Under the transmission electron microscope, placental mesenchymal stem cel s had large nuclei with prominent nucleoli. In the cytoplasm, a plenty of rough endoplasmic reticula was seen, dilated or stacked. The cytoplasm was also rich in Golgi apparatus and lysosomes. The cel surfaces were covered by microvil i. The intercel ular junctions could be seen occasional y. A part of cel s from these five samples could phagocytose fluorescence beads, which ranged from 49.6%to 18.4%. The ultrastructural characteristics of placental mesenchymal stem cel s suggested these cel s were active to synthesize and secrete proteins and had phagocytotic function, indicating placental mesenchymal stem cel s may play a role in keeping the balance of micro-environments and clean the foreign substances in the placenta.
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Organisms are exposed to a variety of stressful condition that damage important cellular structures and interfere with essential functions. In response to heat and other insults, cells activate an ancient signalling pathway leading to the transient expression of heat shock or heat stress proteins (HSPs). HSPs exhibit sophisticated protection mechanisms that protect the damaged cells. HSPs assist in protein folding, translocation and assembly of newly synthesized polypeptides. They also stabilize proteins during heat shock and other stresses, thus contributing to cell survival after injury. The elevated expression of stress proteins is considered to be a universal response to adverse conditions. In this Review we summarize the concepts of the HSPs protective mechanism.