[Comparative studies of different methods in demonstrating Mycobacterium tuberculosis on prepared organ slices with special reference to the phase contrast technic].
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AIMS: This study was designed to evaluate the performance of an automated urinalysis system that utilised three commercially available instruments, the Clinitek Atlas, Sysmex UF-100 and the Alifax Uro-Quick. METHODS: The results of the automated system for 818 urine samples were compared with the results of manual processing which consisted of phase contrast microscopy, manual dipstick chemistry analysis and culture onto solid media. RESULTS: The correlation between the two methods for urine chemistry was excellent with a concordance of 89, 97, 100 and 98% for pH, blood, glucose and protein, respectively. The quantification of red blood cells and white blood cells had an R2 of 0.855 and 0.92, respectively. A difference scatter plot indicated a trend towards the manual cell count being greater than the UF-100 count as both the red and white blood cell count increased. There was 98% agreement between the automated process and manual culture. CONCLUSIONS: The automated urinalysis system is fully integrated and allows for the cross-checking of urine chemistry and microscopy as well as electronic transfer of data. The automated process was used as a screening procedure and some manual testing was necessary. Automation of urinalysis offers a reduction in variation and has comparable results to manual testing.
The use of organic phosphates to avoid calcium phosphate precipitation in parenteral nutrition mixtures has been proposed. The purpose of this study was to evaluate the stability of total parenteral nutrition admixtures containing glucose-1-phosphate or glycerol phosphate as the phosphate source over 3 days. Three parenteral nutrition admixtures, each containing glucose-1-phosphate (30.0 mmol), glycerol phosphate (31.4 mmol) or inorganic phosphate (30.0 mmol), and their corresponding aqueous phases were prepared in 3-L ethylene vinyl acetate plastic bags and infusion bottles, and stored at 5 +/- 1 degrees C or 22 +/- 3 degrees C without light protection. Physical stability analysis and sampling for chemical analysis was performed at 0, 24, 48 and 72 h. Aqueous phases were subjected to physical stability analysis, including pH measurement, visual inspection and nephelometry. Admixtures were subjected to physical stability analysis consisting of pH measurement, and evaluation of emulsion stability by visual inspection, degree of creaming, phase contrast microscopy, zone sensing technique and photon correlation spectroscopy. Chemical analyses of amino-acids, dextrose, triglycerides, phospholipids, Na, K, Cl, Mg, Ca, glucose-1-phosphate, glycerolphosphate and inorganic phosphate were performed. No precipitation was detected in any of the aqueous phases. Admixtures remained acceptable with respect to visual and microscopic appearance, mean droplet diameter and droplet size distribution. All nutrient concentrations assayed in the three admixtures remained constant over the study period. Total parenteral nutrition admixtures for adult patients containing glucose-1-phosphate or glycerolphosphate are physically and chemically stable for 3 days when stored under refrigeration or controlled room temperature without light protection.
A 17-year-old youth presented with bilateral follicular conjunctivitis and nummular subepithelial corneal infiltrates. Failure of this to settle in an outpatient setting led to corneal scraping with microscopy and culturing for bacteria, fungi, Herpes simplex, adenovirus and Acanthamoeba as an inpatient. Polymerase chain reaction analysis of corneal cells was positive for adenovirus, and culture on live Escherichia coli-coated agar plates was positive for Acanthamoeba by phase contrast microscopy on day two. We conclude that Acanthomoeba infection can complicate adenoviral keratoconjunctivitis. This observation is in keeping with previously reported modes of infection by Acanthamoeba, whereby any epithelial breach seems to allow inoculation of the eye by this opportunistic organism.
Interleukin-1 beta (IL-1 beta) strongly inhibited DNA synthesis of adult rat hepatocytes in primary culture stimulated by insulin and epidermal growth factor (EGF). Its effect was dose-dependent and was maximal at 2 ng/ml. IL-1 beta had no cytotoxic effect but changed the cells from a flat to a spindle shape as shown by phase-contrast microscopy. The inhibition of DNA synthesis by IL-1 beta was closely correlated with a decrease in the labeling index. This inhibitory effect was observed only when IL-1 beta was added for 10 h to cultured hepatocytes in the G1 phase within 12 h after addition of insulin and EGF: it was not observed in the S phase, which starts about 24 h after addition of the mitogens. Exposure of the hepatocytes to IL-1 beta for two 1-h periods, one at an early stage (0-6 h) and one at a late stage (6-12 h) of the G1 phase, resulted in the same marked inhibition of DNA synthesis as exposure to IL-1 beta for 10 h in the G1 phase. This requirement of IL-1 beta at two stages in the G1 phase for inhibition of DNA synthesis of hepatocytes is different from that with transforming growth factor-beta, which is required for only 1 h in the early G1 phase for a similar inhibition. These findings suggest that IL-1 beta acts at two distinct stages in the G1 phase and that its cooperative actions are necessary to inhibit growth of adult rat hepatocytes in primary culture. Other cytokines, such as IL-6/B-cell stimulating factor-2, were less potent, but caused significant inhibition of DNA synthesis of adult rat hepatocytes at 2 ng/ml, whereas IL-2 and tumor necrosis factor did not affect hepatocyte growth. From these results it is suggested that Kupffer cells in liver lobules and macrophages in the blood may play important roles, mainly via IL-1, in repair of liver damage and regeneration.
Six strains of Nocardia asteroides, two strains of N. caviae, and two strains of N. braziliensis were grown in medium supplementted with glycine, lysozyme, D-cycloserine, glycine plus lysozyme, and glycine plus D-cycloserine. It was shown that three strains of N. asteroides, and two strains of N. caviae, readily formed spheroplasts and/or protoplasts when grown in the presence of glycine plus either lysozyme or D-cycloserine. This process was studied by both phase contrast microscopy and electron microscopy. The induced cultures were then plated on hypertonic medium for the isolation of L-forms. It was shown that the organisms differed greatly in their ability to produce spheroplasts and subsequently grew as L-forms or transitional-phase variants.
With scanning tunneling microscopy we have found that ordered phases in Pb/Si(111) are one of the best examples of the "devil's staircase" phase diagram. Phases within a narrow coverage range (1.2<theta<1.3 monolayers) are constructed with the rules similar to the ones found in theoretical models.
Restitution of an epithelial layer after environmental or biological damage is important to maintain the normal function of the respiratory tract. We have investigated the role of transforming growth factor (TGF)-beta isoforms in the repair of layers of 16HBE 14o(-) bronchial epithelial-derived cells after damage by multiple scoring. ELISA showed that both latent TGF-beta1 and TGF-beta2 were converted to their active forms 2 h after wounding. Time-lapse microscopy showed that the addition of TGF-beta1, but not TGF-beta2, progressively increased the rate of migration of damaged monolayers at concentrations down to 250 pg/ml. This increase was blocked by addition of a neutralizing TGF-beta1 antibody. Phase-contrast microscopy and inhibition of proliferation with mitomycin C showed that proliferation was not required for migration. These results demonstrate that conversion of latent to active TGF-beta1 and TGF-beta2 during in vitro epithelial wound repair occurs quickly and that TGF-beta1 speeds epithelial repair. A faster repair may be advantageous in preventing access of environmental agents to the internal milieu of the lung although the production of active TGF-beta molecules may augment subepithelial fibrosis.
Salmonella virulence depends on an ability to invade host cells, which is in turn dependent on a type III protein secretion system encoded in Salmonella pathogenicity island 1 (SPI1). Several protein targets of the SPI1-encoded secretion system are translocated into host cells, where they subvert cellular processes that contribute to bacterial invasion, actin rearrangement, membrane ruffling and other aspects of virulence. We examined the role of sipA (encoding the translocated protein SipA) and found that a sipA mutant was significantly less invasive in Madin-Darby canine kidney (MDCK) cells than in its parental strain at the earliest stages of infection (5 min). The invasion defect associated with sipA was no longer apparent after 15 min of infection. Confocal microscopy of F-actin in tetramethyl rhodamine isothiocyanate (TRITC)-phalloidin-stained MDCK cells revealed no difference in either the frequency or the morphology of membrane ruffles induced by wild-type and sipA mutant strains of S. typhimurium. Time-lapse phase-contrast microscopy of membrane ruffle propagation in live cells confirmed that the sipA mutant induced membrane ruffles as efficiently as the wild-type bacteria. These studies also revealed that, after ruffle propagation, individual sipA mutant S. typhimurium either invaded more slowly than wild-type bacteria or failed to invade at all. Furthermore, although wild-type S. typhimurium typically maintained a position central to the developing membrane ruffle, sipA mutant bacteria frequently moved initially to the periphery of the spreading ruffle and were sometimes observed to detach from it. A wild-type pattern of invasion was restored to the sipA mutant after the introduction of sipA on a plasmid. Together, these data indicate that loss of sipA significantly decreases the efficiency of S. typhimurium invasion at the early stages of infection without affecting its ability to induce membrane ruffles. It thus appears that the secreted effector protein SipA promotes invasion by a previously unrecognized mechanism separate from the induction of membrane ruffling per se.
Examination is carried out on dust taken from the atmospheric air in the town of Sevlievo, where a plant for asbestos products is situated. The concentrations of fibre particles are determined by the methods of light and electron microscopy. The results are compared with the emissions of fibres in the air of a control town. There is a significant contribution of an industrial source of emission in the atmospheric pollution by fibre particles. It was proved that the method of light-phase contrast microscopy is not suitable for analyses of low concentrations of fibres in the air. As only reliable method is that of electron microscopy.
A major challenge in microbial ecology is to develop reliable and facile methods of computer-assisted microscopy that can analyze digital images of complex microbial communities at single cell resolution, and compute useful quantitative characteristics of their organization and structure without cultivation. Here we describe a computer-aided interactive system to analyze the high degree of morphological diversity in growing microbial communities revealed by phase-contrast microscopy. The system, called "CMEIAS" (Center for Microbial Ecology Image Analysis System) consists of several custom plug-ins for UTHSCSA ImageTool, a free downloadable image analysis program operating on a personal computer in a Windows NT environment. CMEIAS uses various measurement features and two object classifiers to extract size and shape measurements of segmented, digital images of microorganisms and classify them into their appropriate morphotype. The first object classifier uses a single measurement feature to analyze relatively simple communities containing only a few morphotypes (e.g., regular rods, cocci, filaments). A second new hierarchical tree classifier uses an optimized subset of multiple measurement features to analyze significantly more complex communities containing greater morphological diversity than ever before possible. This CMEIAS shape classifier automatically categorizes each cell into one of 11 predominant bacterial morphotypes, including cocci, spirals, curved rods, U-shaped rods, regular straight rods, unbranched filaments, ellipsoids, clubs, rods with extended prostheca, rudimentary branched rods, and branched filaments. The training and testing images for development and evaluation of the CMEIAS classifier were obtained from 1,937 phase-contrast grayscale digital images of various diverse communities. The CMEIAS shape classifier had an accuracy of 96.0% on a training set of 1,471 cells and 97.0% on a test set of 4,270 cells representing all 11 bacterial morphotype classes, indicating that accurate classification of rich morphological diversity in microbial communities is now possible. An interactive edit feature was added to address the main sources of error in automatic shape classification, enabling the operator to inspect the assigned morphotype of each bacterium based on visual recognition of its distinctive pseudocolor, reassign it to another morphotype class if necessary, and add up to five other morphotypes to the classification scheme. The shape classifier reports on the number and types of different morphotypes present and the abundance among each of them, thus providing the data needed to compute the morphological diversity within the microbial community. An example of how CMEIAS can augment the analysis of microbial community structure is illustrated by studies of morphological diversity as an indicator of dynamic ecological succession following a nutrient shift-up perturbation in two continuously fed, anaerobic bioreactors with morphologically distinct start communities. Various steps to minimize the limitations of computer-assisted microscopy to classify bacterial morphotypes using CMEIAS are described. In summary, CMEIAS is an accurate, robust, flexible semiautomatic computing tool that can significantly enhance the ability to quantitate bacterial morphotype diversity and should serve as a useful adjunct to the analysis of microbial community structure. This first version of CMEIAS will be released as free, downloadable plug-ins so it can provide wide application in studies of microbial ecology.
A new human lung poorly differentiated adenocarcinoma cell line producing carcinoembryonic antigen (CEA) and CA19-9, designated GLL-1, was established from a serial xenograft established in our laboratory. In this paper, we investigated the characteristics of GLL-1 cells. The cell line grew in a monolayer and had a polygonal epithelioid appearance in phase-contrast microscopy. The doubling time of GLL-1 cells during exponential growth was approximately 28 h in RPMI-1640 with 10% fetal calf serum. Positive reactions for CEA and for CA19-9 were seen within the cytoplasm of GLL-1 cells by immunohistochemical staining. In log phase, the fractions for G0/G1, S and G2/M were 76.2%, 20.0% and 3.8%, respectively. Chromosome analysis revealed that GLL-1 cells contained the modal number of 72 chromosomes (range 66-97). GLL-1 cells exhibited numerous numerical and structural abnormalities. The Do value for radiation sensitivity, calculated by taking the reciprocals of the slope of the radiation dose response curve, was 109 cGy. The extrapolation number (n) for the radiation response curve was 1.57. Tumor take was observed in nude mice inoculated subcutaneously in the back with 2 x 10(6) GLL-1 cells. The histopathological features of the tumor induced by inoculation of GLL-1 cells were also the same as the original lung cancer.
Mononuclear phagocytes may be important effector cells against Giardia lamblia. Human monocyte-derived macrophages were incubated with G. lamblia trophozoites in 13% heat-inactivated autologous serum. At a G. lamblia/macrophage ratio of 1:1, the number of trophozoites ingested per 100 macrophages ranged from 1 to 12 at 0.5 h and increased for all donors (n = 6) to 10 to 92 at 8 h. Ingestion was confirmed by electron microscopy. Increasing the parasite/phagocyte ratio to 5:1 increased the percentage of macrophages with adherent but not ingested trophozoites. Incubating Giardia cells and macrophages with 20% immune serum increased ingestion of parasites eightfold, indicating that anti-G. lamblia antibody can enhance ingestion. Both phase-contrast microscopy and electron microscopy documented trophozoite destruction within macrophages. Ingestion of parasites elicited an oxidative burst as measured by luminol-enhanced chemiluminescence. In vitro, Giardia trophozoites were killed by greater than or equal to 5 X 10(-5) M H2O2. Fusion of lysosomes with parasite-containing phagosomes was suggested by acridine orange-stained preparations. Human macrophages have the capacity to ingest Giardia trophozoites and to kill intracellular parasites, possibly by oxidative microbicidal mechanisms.
To examine physical-chemical aspects of bile salt-phospholipid interactions that could contribute to preferential phosphatidylcholine (PC) secretion into bile, we have compared transitions between vesicles and micelles in model systems containing taurocholate (TC) and either egg-yolk PC (EYPC), egg-yolk sphingomyelin (EYSM), buttermilk SM (BMSM) or dipalmitoyl PC (DPPC). Phase transitions from micelles to vesicles were observed at 4-fold dilution of serially diluted EYPC/TC systems, but not earlier than at 16-fold dilution of SM/TC or DPPC/TC systems, indicating lower concentrations of the detergent required for micellization in the case of SM or DPPC. Cryo-transmission electron microscopy of phase transitions initiated by addition of TC to phospholipid vesicles revealed extremely long SM-containing intermediate structures, but shorter EYPC-containing intermediate structures. Again, larger amounts of bile salt were required to induce phase transitions in the case of EYPC compared to SM. Sizes of TC-phospholipid micelles increased progressively upon increasing phospholipid contents in the rank order: DPPC-TC<EYSM-TC<BMSM-TC<EYPC-TC, consistent with higher micellization concentrations in the case of EYPC. Micelles were also separated from vesicular phases in two-phase model systems composed with TC, both EYPC and EYSM and 0, 10, 20 or 30 mol% cholesterol, by ultracentrifugation and ultrafiltration of the supernatant. At increasing cholesterol contents, EYPC preferentially distributed into the micellar phase. In contrast, no preferential micellar EYPC distribution occurred in the absence of the sterol. These results indicate different structural arrangements of EYPC-TC micelles compared to SM-TC micelles and lower detergent concentrations required for micellization in the case of SM-containing vesicles.
Glyceryl monooleate (GMO) is a polar amphiphilic lipid, which forms different sequential lyotropic liquid crystals upon hydration. GMO has been utilized for various delivery systems and routes of administrations. Owing to sticky and waxy nature of GMO, preparation of oral solid dosage form utilizing GMO is still a challenge for pharmaceutical researchers. Therefore, the objective of the present work was to fabricate dry powder precursors using GMO, which upon hydration in situ forms cubic phase and can be wisely used for fabrication of oral solid dosage forms. In addition to this, dry powder precursor was evaluated for drug loading, in vitro release behavior and in vivo performance of model drug diclofenac sodium (DiNa). The dry powder precursor was obtained by spray-drying GMO with DiNa using magnesium trisilicate (MTS) as adsorbent. The percent drug entrapment of various batches of powder precursor was in the range of 84-93% indicating high content uniformity. SEM and image analysis showed that as the amount of MTS in powder precursor was increased, the particle size decreased. Furthermore, the viscosity of powder precursor was function of amount of MTS. The rate of water uptake of powder precursor was higher due to uniform layer of GMO on the MTS surface, which led to faster transformation of lamellar phase into cubic phase. The polarizing light microscopy confirmed that cubic phase was formed upon hydration of powder precursor. The drug released from powder precursor was initially governed by the cubic phase formed and in later stage it depends upon dynamic swelling behavior of hexagonally packed cylindrical aggregates. The drug loaded powder precursor was found to have more effective and prolonged anti-inflammatory and analgesic activity as compared to pure drug. Thus the dry powder precursor of cubic phase was prepared in which drug release was entirely governed by the mesophases formed.
A new cell line producing alpha-fetoprotein, designated NMT-1, was established from rat yolk sac tumor with the potential for lymphatic metastasis in inbred Wistar rats. In this paper, we investigated the characteristics of NMT-1 cells. The cell line grew in a monolayer and had a polygonal epithelioid appearance in phase-contrast microscopy. The doubling time of NMT-1 cells during exponential growth was approximately 16 h in RPMI-1640 with 10% fetal calf serum. The D0 value for radiation sensitivity was 97 +/- 3 cGy. The extrapolation number, n, for NMT-1 was 1.08 +/- 0.15. In the log phase, the G0/G1, S and G2/M fractions were 23.2%, 62.1% and 14.3%, respectively. Tumor take was observed in all of the rats inoculated with NMT-1 cells. In the case of flank tumor, the mean survival time was 104 days after inoculation with 10(6) tumor cells. Inguinal, axillary, paraaortic, mesenteric and mediastinal lymphnode metastases were observed in all rats inoculated with NMT-1 cells. Rats which survived for a long time developed metastases in a lymphatic vessels of the liver, lung and/or kidney microscopically. The biological behavior and the histopathological features of the tumor induced by inoculation with NMT-1 cells were the same as those of the original tumor induced by fetectomy.
The structural phase transition of Pr(1-x)Ca(x)MnO(3)(x = 3/8) was investigated by means of low-temperature transmission electron microscopy. Superlattice reflection spots with a modulation wave vector q(1) = (0,1/2,0) appeared below 230 K, indicating formation of the d(3x(2-r(2))/d(3y(2)-r(2)) type of charge/orbital ordering. Below 150 K, a new series of superlattice reflection spots with a modulation wave vector q(2) = (1/4,1/4,1/2) appeared, suggesting an additional ordering of excess 1/8 Mn(3+), necessary due to the deviation of x from 1/2, with the occupation of the d(3z(2-r(2)) type of e(g) orbital.
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