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[The regression analysis of the in hospital medical staffs infection rate and the application of the isolation measures including the emergency-isolation radiology information system].

OBJECTIVE: To analyze the relationship between the rate of the in-hospital medical staff SARS infection and the measure of isolation which including the application of the emergency-isolation radiology information system (EIRIS) in polyclinic. METHODS: The groups were classified according to the application of the prevention and protection measure. Group A referred to the stage before the declaration of infectious area was made. Group B was defined as the stage in which the application of common measures of the prevention and protection were made, but the isolation measure was not taken (the suspected or diagnosed cases had the chest X ray film examination in the department of radiology). Group C was the stage after the startup of the isolation measure including the application of EIRIS. the number of the diagnosed cases, the medical staffs exposed, and the diagnosed cases of medical staffs were recorded. RESULTS: In group A, the infectious rate of in-hospital medical staffs showed a marked ascending trend with the regression coefficient of 0.000545, P = 0.04. The rate showed a little descending trend in Group B compared with that in Group A with the regression coefficient of 0.000164, P = 0.140. While marked descending trend compared with group A was demonstrated in group C with the regression coefficient of 0.000037, P = 0.02. CONCLUSION: The trend of the in-hospital medical staffs infection rate changed with different style of prevention and protection measures. With the application of the common measure of the prevention and protection, the rate was significantly lower than that in group A. After the application of the isolation measures including EIRIS, the rate showed the descending trend much further.

Emergencies↗

Isolated limb perfusion for localized melanoma of the extremity. A matched comparison of wide local excision with isolated limb perfusion and wide local excision alone.

The therapeutic efficacy of isolated limb perfusion in patients with localized melanoma of the extremity remains controversial. We compared patients treated at the University of Texas M.D. Anderson Cancer Center, Houston, with wide local excision and isolated limb perfusion using either melphalan or imidazole carboxamide with a group matched for prognostic factors from the University of Alabama at Birmingham and the University of Sydney (Australia) who were treated with wide local excision alone. No significant difference in disease-free or overall survival rates was found between patients treated with wide local excision with adjuvant isolated limb perfusion or wide local excision alone. However, a subset of patients with thicker lesions (greater than 2.0 mm) treated with wide local excision and isolated limb perfusion using melphalan had a significant improvement in both disease-free and overall survival rates. These data suggest that isolated limb perfusion using melphalan may improve survival rates in selected patients with localized melanoma of the extremity who are at increased risk for local and regional micrometastases, and justifies the continued study of this treatment approach in prospective clinical trials.

Aminoimidazole Carboxamide↗

Production, characterization and application of protein isolates from shark. Part 3. Characterization of protein isolates.

The functional and nutritional characterization of two isolates elaborated through cleaning-extraction processes, as well as that of a third isolate obtained by means of a chemical modification (alkaline heat treatment) from one of the former, was carried out. The first two isolates exhibit in general similar properties, are nutritionally comparable with casein and show a fairly high water absorption, having a potentially great value for instance in bakery and meat products and pastes. The modified isolate is essentially different from the isolate used as raw material in many of the characterized parameters, having a high nitrogen solubility index (NSI) by pH 3.5 and 7.0 and thus offering its possible use in such food systems as soft drinks where a high solubility is desired.

Amino Acids↗

Isolation of porcine pancreatic islets: low trypsin activity during the isolation procedure guarantees reproducible high islet yields.

During the past few years, interest in xenotransplantation of porcine islets of Langerhans for the future therapy of type I diabetes has increased markedly. Therefore, we established a semiautomated digestion method for isolating islets from the porcine pancreas. However, although the isolation technique was standardized and collagenase of controlled quality was used, we were unable to attain high islet yields with a satisfactory degree of reproducibility. One hypothesis was that varying degrees of interference by donor pancreatic enzymes were responsible for this failure. The aim of this study was to examine the kinetics of four types of enzymatic activity during the isolation procedure, as well as their effects on islet yield: collagenase, trypsin, neutral protease, and clostripain. Our results indicate that while exogenous collagenase activity decreases slightly during the isolation procedure, the activity of the pancreas enzymes neutral protease and trypsin increases. In some cases, trypsin activity increases very strongly. A strong increase in trypsin activity correlates with poor islet yield, whereas low trypsin activity always correlates with high islet yield. Addition of the protease inhibitor Pefabloc to the isolation medium results in low trypsin activity and reproducible high islet yields.

Animals↗

Isolation and characterization of a polarized isolated hepatocyte preparation in the skate Raja erinacea.

Hepatocytes of the small skate (Raja erinacea) were isolated by collagenase perfusion and evaluated by a variety of functional and morphologic criteria. Cell yield was 1.45 X 10(8) +/- 1.3 X 10(7) cells per isolation, and as long as 8 h after isolation 98% of the hepatocytes excluded Trypan blue and no leakage of lactate dehydrogenase (LDH) or cell associated potassium could be detected. Oxygen consumption averaged 1.6 +/- 0.5 nmol/min/mg cell protein, was not stimulated by 1 mM succinate, and also remained stable for up to 8 h following isolation. However, 2,4,-dinitrophenol (5 X 10(-5) M) produced a 55% increase in oxygen utilization while ouabain, (1 mM) or sodium removal decreased oxygen consumption by 31 +/- 6 and 33 +/- 7%, respectively, indicating that a significant portion of the cells energy utilization is coupled to the activity of plasma membrane Na+, K+-ATPase. Light microscopic studies showed that the individual hepatocytes had diameters of 28 +/- 5 microns and contained large lipid droplets. Electron microscopy revealed groups of three to five cells with normal ultrastructure and tight junctions and desmosomes surrounding a single bile canaliculus. These studies indicate that skate hepatocytes can be isolated in high yield that retain their structural polarity in the form of clusters of cells formed around a single bile canaliculus. These hepatocytes remain morphologically intact and metabolically stable for a prolonged period of time.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Improvement of Clostridium difficile isolation by heat-shock and typing of the isolated strains by SDS-PAGE.

Clostridium difficile plays an essential role in causing pseudomembranous colitis. We looked for the presence of these bacteria in the stools of 169 hospitalized patients and 38 nurses from wards with cases of diarrhea (207 subjects). The study was divided into three parts. In the first part, we compared three methods for isolating Clostridium difficile from stool samples: pre-selection with heat-shock, direct plating on Cycloserine-Cefotaxime-Fructose Agar (CCFA) and culturing in a selective broth medium. Final identification of Clostridium difficile was achieved by gas-chromatography and ApiZym. From the 207 consecutively obtained stool specimens, Clostridium difficile was isolated in 108 (52%) when pre-treated by heat-shock compared to only 26 (13%) when plated on modified CCFA and 23 (11%) when cultured in selective broth medium. Pre-selection significantly increases the isolation rate for Clostridium difficile and should be used in further epidemiological research. In the second part of our study, a retrospective review of subjects' records showed that the heat-shock method detected Clostridium difficile in all age groups at a higher rate than the other methods. In the third part of our study, we typed the 157 isolates of Clostridium difficile strains by protein patterns using SDS-PAGE, and 16 distinct groups were identified. In 19 cases different Clostridium difficile strains were found in the same subject by SDS-PAGE. Finally, the isolated strains were compared with strains from Brussels and Freiburg. Matching patterns were noted in only three cases.

Adolescent↗

The isolation of Cryptococcus neoformans from pigeon droppings and serotyping of naturally and clinically sourced isolates in China.

This is the first report on the isolation of Cryptococcus neoformans from pigeon droppings in China and their serotypes. C. neoformans colonies which produced brown colonies on caffeic acid-cornmeal agar were found in Twenty-five out of thirty-six samples of pigeon droppings. Fifty-one colonies randomly picked from the positive samples were identified as C. neoformans by a commercially available kit for carbon source assimilation test and Christensen's urea agar. Forty (78%) out of the 51 strains were serotyped as A and 11 (22%) as AD. At the same time, seventeen out of nineteen clinical isolates were serotyped as A and 2 as B. There are three findings in our results. One is that only C. neoformans var. neoformans strains could be isolated from pigeon droppings, although the variety gattii strains were found in the clinical isolates obtained in the same geographic site in China. The second is that serotype A strains were most frequently seen in natural and clinical materials in the southeast part of China, and serotype AD strains were isolated in pigeon droppings but not in clinical materials. The third is that the coexistence of serotype A and AD cells of C. neoformans strains in same samples of pigeon droppings were observed.

Animals↗

Isolation and characterization of polycyclic aromatic hydrocarbon-degrading Mycobacterium isolates from soil.

Bioremediation of soils contaminated with wood preservatives containing polycyclic aromatic hydrocarbons (PAHs) is desired because of their toxic, mutagenic, and carcinogenic properties. Creosote wood preservative-contaminated soils at the Champion International Superfund Site in Libby, Montana currently undergo bioremediation in a prepared-bed land treatment unit (LTU) process. Microbes isolated from these LTU soils rapidly mineralized the (14)C-labeled PAH pyrene in the LTU soil. Gram staining, electron microscopy, and 16S rDNA-sequencing revealed that three of these bacteria, JLS, KMS, and MCS, were Mycobacterium strains. The phylogeny of the 16S rDNA showed that they were distinct from other Mycobacterium isolates with PAH-degrading activities. Catalase and superoxide dismutase (SOD) isozyme profiles confirmed that each isolate was distinct from each other and from the PAH-degrading mycobacterium, Mycobacterium vanbaalenii sp. nov, isolated from a petroleum-contaminated soil. We find that dioxygenase genes nidA and nidB are present in each of the Libby Mycobacterium isolates and are adjacent to each other in the sequence nidB-nidA, an order that is unique to the PAH-degrading mycobacteria.

Base Sequence↗

The complete nucleotide sequence of a severe stem pitting isolate of Citrus tristeza virus from Spain: comparison with isolates from different origins.

The genomic RNA of the severe stem pitting Citrus tristeza virus (CTV) isolate T318A from Spain (19252 nt) was completely sequenced. It showed strong sequence similarities with the severe isolates SY568 from California and NUagA from Japan, and distant relationships with mild non-stem pitting isolates T385 from Spain and T30 from Florida. Contrasting with other severe CTV isolates, T318A had a predominant sequence variant even in the highly variable 5'-terminal untranslated region, in which a unique sequence variant (type II) previously associated with severe stem pitting isolates was detected. The high homogeneity of the T318A population suggests that the sequence obtained is probably responsible for the symptoms induced and makes it a useful tool to delimit pathogenicity determinants.

Base Sequence↗

Isolation and primary culture of viable multicellular endothelial isolates from hard corals.

Conditions for the primary culture of branching scleractinian coral (Acropora micropthalma and Pocillopora damicornis) cells were established with a calcium-free seawater cell dissociation method. Cells were isolated and cultured in supplemented Dulbecco's modified Eagle media with heat-inactivated fetal bovine serum, antibiotics, and sterile seawater. Among the isolated cell types, large (60-100 microm) multicellular endothelial isolates (MEIs) were seen in high numbers. These isolates were observed to continually spin for up to 300 h without media change. The following parameters were optimized: media, serum, light, trace elements, and growth factor supplements. Rotations per minute were calculated to determine MEI motility in relation to size. Finally, analyses of external and internal structures were conducted with scanning electron microscopy, transmission electron microscopy, and fluorescence microscopy. Additional coral species, Montipora digitata, Stylophora pistillata, Seriatopora hystrix and Porites sp. were also cultured to determine the applicability of isolation techniques. The relatively long survival time of MEIs in primary culture makes them ideal candidates for in vitro studies examining coral disease processes (e.g., mode of infection and intracellular effects of disease-causing agents) as well as aspects of general coral growth and health (e.g., trace element requirements and transfer of products between host cell and zooxanthellae).

Animals↗

Procedure for isolation of gangliosides in high yield and purity: simultaneous isolation of neutral glycosphingolipids.

While several methods for ganglioside extraction and isolation have been described, relatively little attention has been given to the effectiveness of separation from peptides, phospholipids, and various low-molecular-weight contaminants. A procedure is described for isolation of gangliosides in high purity and good yield from 1- to 400-mg samples (wet wt). A key step was mild acidification following homogenization, designed to dissociate gangliosides from lipophilic peptides which coextracted into organic solvents. This has proved particularly helpful for myelin and myelin-containing tissues (e.g., white matter, nerve) whose proteins have presented special problems in ganglioside isolation. In this study isolation was effected by consecutive chromatographies on Sephadex LH-20, DEAE-Sephadex, and silica gel following the initial acidification. The method applied to bovine white matter gave tissue concentrations (calculated from yields and radiolabeled tracer recoveries) that were similar to those obtained with three previously described procedures; however, peptide contaminants were an order of magnitude lower. Removal of low-molecular-weight contaminants, including nucleotide sugars, was virtually complete. In addition to ganglioside isolation the method can be used to obtain neutral glycosphingolipids as well. It is believed to have broad applicability to a diversity of tissues.

Animals↗

Highly insulin-responsive isolated rat heart muscle cells yielded by a modified isolation method.

Freshly isolated adipocytes or cardiac myocytes appear to be subject to unspecific stimulation during isolation and subsequent handling, e.g. with respect to glucose transport. We have developed a modified procedure that yields rat cardiomyocytes with a very low basal, i.e. non stimulated hexose uptake rate (ca. 3 pmol * s-1 * mg protein-1 at 1 mM sugar), as compared to data reported by others. This low value correlates with the reported oxygen consumption of non-beating, isolated rat hearts, when these are perfused with glucose as the only substrate. The basal rate of glucose uptake in our quiescent cardiomyocytes is slightly lower than the value measured by others in beating rat hearts in vivo. Insulin (10 nM) stimulates 2-deoxy-D-glucose uptake 8- to 20-fold and 3-O-methyl-D-glucose uptake 14- to 20-fold, as compared to control. This insulin effect is markedly larger than that usually observed in isolated cardiomyocytes, but it is similar in magnitude to the stimulation of glucose transport reported for isolated, perfused rat hearts. In these cells, new stimulatory effects on the glucose transport, e.g. that of sulfhydryl reagents like phenylarsine oxide, become apparent. We conclude that the cardiomyocytes obtained by this modified method exhibit a basal glucose transport rate that is close to physiological values. These cells represent a new highly responsive model to detect and to investigate the effects of glucose transport stimulators (insulin, contraction etc.).

3-O-Methylglucose↗

Envelope gene sequence of HTLV-1 isolate MT-2 and its comparison with other HTLV-1 isolates.

The DNA sequence of the envelope gene of the HTLV-1 proviral clone MT-2 was determined and compared with envelope sequences of other HTLV-1 isolates. The comparison of this sequence with another of Japanese origin and two of Caribbean origin does not support the proposal by K.T.A. Malik, J. Even, and A. Karpas (J. Gen. Virol. 69, 1695-1710, 1988) that isolates of similar geographic origins are more homologous than isolates of different origins. No significant differences in the degree of homology could be found among the HTLV-1 envelope gene sequences from Japanese and Caribbean isolates. The comparison confirms the high degree of homology previously found between various HTLV-1 isolates (greater than 97%).

Amino Acid Sequence↗

Isolation of lactic acid bacteria from Malaysian foods and assessment of the isolates for industrial potential.

Two traditional fermented food 'tapai' (fermented tapioca) and 'tempoyak' (fermented durian flesh), chilli puree and fresh goat's milk were used as sources for the isolation of lactic acid bacteria (LAB). A total of 126 isolates were obtained and by sequential screening for catalase activity and Gram-staining, 55 were determined to be LAB out of which 16 were established to be homofermentative by the gel plug test. Seven isolates were identified by use of the API 50CHL kit and two lactobacilli strains and one lactococci strain were selected to study their growth and lactic acid production profiles in a time course experiment. The lactobacilli strains, both isolated from 'tapai', produced higher amounts of cells and lactic acid from glucose as compared to the lactococci strain isolated from fresh goat's milk.

Animals↗

Isolates of Staphylococcus aureus and saprophyticus resistant to antimicrobials isolated from the Lebanese aquatic environment.

The indiscriminate use of antimicrobials especially in developing countries has evoked serious bacterial resistance and led to the emergence of new and highly resistant strains of bacteria to commonly used antimicrobials. In Lebanon, pollution levels and bacterial infections are increasing at a high rate as a result of inadequate control measures to limit untreated effluent discharges into the sea or freshwater resources. The aim of this study was to isolate and molecularly characterize various Staphylococcus strains isolated from sea water, fresh water, sediments, and crab samples collected from representative communities along the coast of Lebanon. The results on the antimicrobial resistance indicated that the level of resistance of Staphylococcus aureus varied with various antimicrobials tested. The resistance patterns ranged between 45% in freshwater isolates and 54.8% in seawater ones. Fifty one percent of the tested isolates have shown resistance to at least one of the five tested antimicrobials; with seawater isolates exhibiting the highest rates of antimicrobial resistance.

Animals↗

Isolation and characterisation of Beauveria bassiana isolates from phylloplanes of hedgerow vegetation.

A leaf imprinting technique combined with a selective medium was used to document the natural occurrence of Beauveria bassiana on phylloplanes of typical hedgerow plants (grasses, stinging nettle and hawthorn) in May, July and September in a hedgerow in Denmark. The density of B. bassiana (as measured by numbers of colony forming units) was greatest in September and on lower nettle leaves. B. bassiana was isolated from phylloplanes in a different hedgerow the following year and a similar picture of occurrence was found. Genetic diversity of selected in vitro isolates were characterised by Universally Primed (UP) PCR, and 13 distinguishable banding patterns were found at the two localities. Of these, four were shared between the field sites and all plant species harboured isolates of B. bassiana with at least two different banding patterns. The isolation method described represents a valuable tool for studying naturally occurring B. bassiana and for rapid isolation of indigenous strains of the fungus for future development of biocontrol agents. The significance of the findings for the life-cycle of B. bassiana is discussed.

Colony Count, Microbial↗

Validation of the scoring system for standardization of the pancreatic donor for islet isolation as used in a new islet isolation center.

BACKGROUND: The aim of this study was to evaluate the effectiveness of the Edmonton Donor Scoring System for use in our much less active islet center. Because the ability to recognize an appropriate donor may help to achieve consistent and predictable success of pancreatic islet isolation, it should lead to increased effectiveness and lower cost. MATERIAL AND METHODS: Charts of 36 consecutive pancreas donors were reviewed to assess the donor points (DP). DP ranged from 0 to 100 based on donor age, body mass index, cause of death, social and medical history, hospital stay, vasopressor dosages, laboratory tests, cold ischemia time and procurement team, as well as pancreas size, consistency, fat content, damage, and quality of procurement and packing. RESULTS: Successful isolation was achieved in 39% of donors (14 of 36), a value similar to that achieved in Edmonton (40%). We used the optimal cutoff value (DP = 79) proposed by the Edmonton group. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 66%, 75%, 57%, 82% and 72%, respectively. Successful islet isolation from poor or marginal donors (DP < 49.5 and 50 to 59.5) was 0% and 28.6% respectively; it was 63% and 100% in optimal donors (DP = 80 to 89.5 and 90 to 100). We concluded that islet isolation success correlated with the previously proposed donor scoring system. CONCLUSIONS: The Donor Scoring System can be successfully implemented regardless of the level of activity of an experienced isolation center. This system permits identification of a suitable donor prior to organ processing. It may guide a center's donor selection strategy based on its goals and its budget.

Adult↗

An update on high-yield hepatocyte isolation methods and on the potential clinical use of isolated liver cells.

Isolated hepatocytes are a suitable system for the study of hepatic physiology and metabolism. They are also used for pharmacological and toxicological studies related to hepatic uptake, metabolism, excretion and toxicity of xenobiotics, as well as morphological and metabolic effects induced in the liver as a result of drug or toxic substance exposure. In this paper, the enzymatic methods for hepatocyte isolation in some mammalian species are reviewed, and methods for evaluating cell purification and assessment of cellular morphology and function are also examined. More recently, interest in hepatocyte transplantation has increased, and the clinical experimentation of hepatocyte-based liver support systems has attracted the attention of scientists and hepatologists. From a clinical perspective, using isolated hepatocytes could be useful both for supporting an acutely devastated liver, a chronically diseased liver, and for correcting genetic disorders resulting in metabolically deficient states. Reports of clinical usage of isolated allogenic hepatocytes in hepatocellular transplantation and of xenogenic liver cells in constructing bio-artificial liver support systems are promising, and are renewing interest in the development of methods for isolation and purification of hepatocytes.

Animals↗