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At least 703 records · Page 39Linked to original sources
PubMed1994

Human islet isolation in 104 consecutive cases. Factors affecting isolation success.

One of the major steps toward successful islet transplantation for the treatment of type diabetes is to obtain islets of sufficient number and viability. Using a standardized method of isolating islets, the goal of this study was to analyze the factors influencing the outcome of islet isolation. A total of 104 cadaveric human pancreata were processed for islets by the same team. Data from the islet-processing charts were reviewed retrospectively. The two endpoints were the recovery of islets, viable after 2 days of culture (group V = viable, group NV = nonviable) and the islet yield. Viable islets were recovered in 61% of cases (n = 63). Minimal blood glucose recorded during hospitalization was very significantly lower in group V (124 +/- 5 vs. 148 +/- 9, P = 0.01). Lack of significant medical history in the donor was associated with better viability as compared with various donor predispositions (chi-2 4.21, P = 0.04). Cold ischemia time (8.1 +/- 0.5 hr in group V vs. 9.8 +/- 0.9 hr in group NV, P = 0.07) and collagenase lot (5 lots tested, chi-2 13.1, P = 0.01) also affected the recovery of viable islets. Hospital time was shorter in group V (65.3 +/- 6.8 vs. 80.9 +/- 17.9 hr, P = 0.35). Multivariate logistic regression analyses of viable islet recovery identified minimal blood glucose (P = 0.03) and collagenase lot (P = 0.06) as the most significant risk factors. However, the best multivariate predictive model--which includes blood glucose, collagenase lot, donor age and surgical procurement team--correctly predicted 66.2% of cases only. Multivariate analysis of final islet yield designed hospitalization length, cardiorespiratory arrest, surgical procurement team, and collagenase lot as the best predictors. These data obtained in a large series of pancreata emphasized several donor and technical factors that should target the attention of islet transplant researchers in order to improve islet yield and viability.

Adolescent↗
PubMed1994

Effects of pimobendan on isolated human right atria strips and on isolated left atria of the rat.

The present study describes the effects of pimobendan on isolated human right atrial strips and on isolated left atria of the rat. Pimobendan induces a positive inotropic effect both in human and rat preparations. The maximal increase (28 +/- 2.0%) obtained with pimobendan in the strips from human right atria was similar to that obtained in left atria of the rat (31 +/- 1.8%). These observations may have some clinical relevance as pimobendan might prove to be an alternative to catecholamines for inotropic support in patients who undergo general anaesthesia.

Animals↗
PubMedDate not supplied

Serotypes of Salmonella isolated from California turkey flocks and their environment in 1984-89 and comparison with human isolates.

Serotypes of Salmonella from turkeys and their environment identified at the California Veterinary Diagnostic Laboratory System (CVDLS) between 1984 and 1989 are reported. Between 1988 and 1989, Salmonella serotypes from turkeys were compared from two sources: from routine submissions to the CVDLS (primarily associated with the National Poultry Improvement Plan), and from a random sample of turkey farms conducted by the National Animal Health Monitoring System (NAHMS). Serotype isolation frequencies were ver similar under these two systems. Serotypes identified most frequently under both systems were (listed from most to least frequent): Salmonella kentucky, S. anatum, S. heidelberg, S. reading, and S. senftenberg. This isolation pattern was different from that found in humans in California; only S. heidelberg was relatively common in both humans and turkeys during this period.

Animals↗
PubMed1993

[Isolation of Methylobacterium spp. from drinking tank-water and resistance of isolates to chlorine].

On bacteriological examination of 100 samples of drinking tank water, standard plate count bacteria (36 degrees C, 24 h) and coliforms were not detected, conforming to the water quality criteria under the Water Supply Law. Ninety-five percent of test samples had concentrations of residual chlorine exceeding 0.1 mg/l. However, one characteristic heterotroph was isolated from 70% of these water samples. The bacteria showed glucose non-fermentative Gram-negative rods and formed pink colonies when cultured on standard agar medium at 30 degrees C for 7 days. It was oxidase-positive, catalase-positive and motile. Furthermore, utilization of methyl alcohol was a characteristic. From these characteristics, it was identified as genus Methylobacterium. The isolated Methylobacterium of 118 strains were divided into 60 types using 20 biochemical tests. Thirty Methylobacterium strains were examined for tolerance to chloride by contact with free residual chlorine of 0.1 mg/l concentration for 5 min. Considerable resistance to residual chlorine was evident. The TW-7 strain showed especially high tolerance, even surviving contact at 1.0 mg/l concentration of free residual chlorine for 10 minutes.

Chlorine↗
PubMed1993

Isolation, purification, toxicity and some physicochemical properties of mycotoxins produced by aspergillus quadrilineatus isolated from acha (Digitaria exilis stapf) in Plateau State of Nigeria.

Some physico-chemical and toxicological studies were carried out on mycotoxins elaborated by Aspergillus quadrilineatus isolated from a grain foodstuff, acha (Digitaria exilis) in the Plateau State of Nigeria. The mycotoxins produced by A quadrilineatus were extractable from rice culture by chloroform. Column chromatographic separations of the crude extract in silica gel using different elution solvents and biological tests showed that the mycotoxins came off in the diethylether, chloroform and mostly in the ethyl acetate fractions. Use of different available mycotoxin standards on silica gel G coated chromatoplates revealed that 1 of the mycotoxins produced by A quadrilineatus was sterigmatocystin. Two other more toxic mycotoxins were isolated and purified from the crude chloroform extract; their column, preparative thin-layer chromatographic, infrared and UV-spectrophotometric characteristics were established. The infrared spectra of the 2 purified mycotoxins suggested that the carbonyl group of their structures were similar to that of aflatoxin.

Animals↗
PubMed1995

Is isolated systolic hypertension in the elderly more associated with left ventricular hypertrophy and significant carotid artery stenosis than mixed hypertension and isolated diastolic hypertension?

The association of electrocardiographic left ventricular hypertrophy (ECG-LVH) (212 subjects) and haemodynamically significant internal carotid artery stenosis (ICAS) (27 subjects) with isolated systolic hypertension (ISH), mixed hypertension (MHT) and isolated diastolic hypertension (IDH) was studied in untreated elderly patients. Subjects were those aged 67-86 years, drawn from a community screening programme for hypertension in Wales. The prevalence of ECG-LVH with or without repolarisation abnormalities was higher in subjects with ISH (16.6%) than in subjects with mixed hypertension (11.6%, NS). Partial correlation of SBP, DBP, voltage of lead I and SV1+RV5 for each hypertensive subtype showed a consistent positive correlation of DBP with the voltage of lead I and SV1+RV5 in all the subtypes except with the voltage of lead I in IDH subjects. In MHT, the SBP was inversely related to both the voltage of R-wave in lead I and SV1+RV5 (P < 0.03). In IDH, the SBP was positively correlated with the voltage of R-wave in lead I and inversely with SV1+RV5. Atheromatous plaque was present in 40 of 54 (74.1%) internal carotid arteries investigated. The homogeneous type of plaque was predominant in ISH (67%). Heterogenous type of plaque was predominant in the MHT group (50%) and IDH group (43%). The normotensive group did not show any predilection to any morphological type. Plaque was invariably present in the case of ISH, chi 2 = 12.29, 0.1 > P > 0.05. There was more smooth plaque surface in normotensives (79%) and more rough or pitted plaque surface in hypertensives (all types), chi 2 = 6.51, 0.1 > P > 0.05. All normotensives and IDH subjects had non-haemodynamically significant stenosis. Haemodynamically significant stenosis was found in cases of ISH (25%) and MHT (7%); chi 2 = 7.66, 0.1 > P > 0.05. ECG-LVH and haemodynamically significant internal carotid artery stenosis were more commonly found in subjects with ISH than in subjects with MHT. Further studies with larger numbers of patient in each hypertensive subtype would be desirable to confirm these observations.

Aged↗
PubMedDate not supplied

[Antigenic determinants in the composition of the hemagglutinins of the influenza virus H1N1 isolated in 1977 and of the H1N1 viruses isolated in 1947--1956].

A comparative analysis of hemagglutinins (HA) of the A/USSR/090/77 (H1N1) virus isolated in 1977 and A/FM/47, A/Leningrad/49, A/Pan/52, and A/Netherlands/56 viruses with the antigenic formula (H1N1) was done. By the method of cross adsorption of rabbit influenza antisera, HA of the viruses under study were found to contain three antigenic determinants: one is common for all the variants studied, another characterizes the relationships of individual variants isolated in different years, and the third is strain-specific, determining the antigenic differences between the variants. According to our results, the influenza A/USSR/090/77 (H1N1) virus has in its HA three antigenic determinants closely related or identical to those of HA of a/leningrad/49 and A/Pan/52 viruses.

Animals↗
PubMed1977

[Conditions for glycogen retention in smears of isolated cells. I. Cytofluorimetric analysis of glycogen content in cells obtained by different methods of isolation].

A cytofluorimetrical study was made of glycogen content on smears of isolated rat liver cells, obtained by perfusion of different solutions: 1/15 M phosphate buffer, the Locke solution, only the Locke solution plus sodium citrate, a calcium-free Locke solution, 0.25 M sucrose, physiological saline, Versene. No loss of glycogen occurred during any perfusion procedure, however, it took place during the smear preparation. The main cell injury is observed due to mechanical factors. An additional treatment of liver, after perfusion, by homogenization and centrigugation at mild conditions decreases the cell glycogen content by 30%. The least cell injury and the best glycogen retention was achieved when phosphate buffers were employed for cell isolation.

Animals↗
PubMedDate not supplied

[Phenotypic characteristics of HIV isolates, isolated in the Belarus Republic].

Biological characteristics of 26 HIV strains circulating in the Republic of Belarus were studied in cell cultures. By the replicative activity, infectivity, and tropism to certain cell lines, all the strains can be divided into 2 groups: rapid/high and slow/low. Slow/low HIV strains were isolated from asymptomatic patients with lymphadenopathy and from AIDS patients. On the other hand, two rapid/high strains were isolated from patients without clinical signs of AIDS 6-8 months after probable infection.

Acquired Immunodeficiency Syndrome↗
PubMed1991

[Infections in the neutropenic phase following bone marrow transplantation: comparison of laminar airflow isolation with conventional isolation].

From May 1978 to September 1989 45 patients underwent 25 allogeneic and 21 autologous bone marrow transplantations (BMT) and 1 peripheral stem cell transplantation for the following indications: severe aplastic anemia (n = 4), hematological malignancies (n = 28), malignant solid tumours (n = 12) and sideroblastic anemia (n = 1). The first group of 20 patients was isolated in a conventional hospital room, while management of the aplastic phase in the second group of 25 patients was performed in a laminar air flow (LAF) unit. All patients received total decontamination. In a retrospective analysis the number of positive blood cultures during the neutropenic period was 85% in the first group, as compared with 40% in the second group, and the number of febrile episodes was 85% versus 64%, respectively. Despite the fact that the septic morbidity was lower in the LAF group, mortality during the neutropenic period (15% in group I versus 16% in group II) was unaffected and survival rate (45% in group I versus 36% in group II) did not improve. We conclude that LAF protection will only have a positive impact on survival rate if the incidence of non-infectious complications of BMT, such as organ toxicity or graft-versus-host disease, is likewise reduced.

Adolescent↗
PubMed2004

Detection, isolation, and characterization of exopolysaccharide produced by a strain of Phormidium 94a isolated from an arid zone of Mexico.

Phormidium 94a, a cyanobacteria that produces extracellular polymeric substances (EPS), was isolated from arid soils of Mexico. Microscopic localization, using histochemical techniques like the Toluidine blue technique, was done in order to demonstrate the presence of EPS. Acetone was added to precipitate the EPS. In this study we characterized the EPS by GC, HPLC, and IR techniques. The highest fraction of EPS had a molecular weight of 2000 kDa. The sugar composition was galactose, mannose, galacturonic acid, arabinose, and ribose in the three main fractions, and the sugar ratio found was different in each fraction. The low EPS concentrations had a Newtonian behavior, when the concentrations were increased, the behavior changed to pseudoplastic. The EPS rheulogical behavior is similar to low viscosity arabic gum. Also, it was found that an increase in viscosity occurred at longer hydration time. More rheological and toxicological studies are required in order to analyze its possible application in food industries.

Cyanobacteria↗
PubMed2003

Isolation and characterization of an indigenous isolate of Dunaliella sp. for beta-carotene and glycerol production from a hypersaline lake in India.

Dunaliella, a green alga grows in a wide range of marine and freshwater habitats such as oceans, brine lakes, salt marshes and salt-water ditches near the sea, predominantly in water bodies containing more than 10% salt. Sambhar salt lake, Rajasthan (India) was found as one of the natural habitat of Dunaliella sp. The species was isolated and screened for accumulation of beta-carotene and glycerol. It was studied for the growth attributes like total protein, optical density, total chlorophyll, total carotenoid, beta-carotene and glycerol. Under unstressed physico-chemical conditions the maximum beta-carotene and glycerol observed was 1.15 pg/cell and 94.26 pg/cell respectively. The stress (salt stress (NaCl), high light intensities and continuous light) allowed the alga to accumulate high beta-carotene (approximately 4.21 pg/cell under 118.18 micromole m(-2) s(-1) of light intensity) without massive reduction in biomass content. This opens up new avenues for exploring this strain for future research and its commercial exploitation.

Algal Proteins↗
PubMed1997

Insulin secretagogues with an imidazoline structure inhibit arginine-induced secretion from isolated glucagon secretion from isolated rat islets of Langerhans.

It is well documented that imidazoline compounds such as efaroxan and phentolamine act as potent insulin secretagogues both in vivo and in vitro, an effect which is mediated principally by blockade of ATP-sensitive potassium channels in the pancreatic B-cell. However, little is known about the effects of these drugs on the secretion of other pancreatic hormones and, in the present work, we have investigated the effects of selective imidazoline compounds on glucagon release from isolated rat islets of Langerhans. None of several imidazoline compounds tested (efaroxan, phentolamine, idazoxan, antazoline) affected glucagon secretion from islets incubated with 4 mM glucose. However, when the rate of glucagon release was stimulated by L-arginine (20 mM) efaroxan caused a rapid, sustained and dose-dependent inhibition of the secretory response (EC50 approximately 30 microM). This effect was seen under both static incubation and islet perifusion conditions. Antazoline and phentolamine also inhibited arginine-induced glucagon secretion, whereas idazoxan (an imidazoline which does not affect insulin secretion) failed to alter glucagon release. The inhibitory effects of imidazolines on glucagon release were not secondary to changes in insulin secretion. Taken together, the results indicate that pancreatic A-cells express functional imidazoline receptors which can regulate the secretory activity of the cells.

Animals↗
PubMed2000

Antigenic properties of recombinant envelope glycoproteins derived from T-cell-line-adapted isolates or primary human immunodeficiency virus isolates and their relationship to immunogenicity.

The native envelope glycoproteins of primary HIV-1 virions have weaker antigenicity than do T-cell laboratory-adapted (TCLA) viruses. These antigenic properties require further evaluation if recombinant envelope glycoproteins are produced as part of a vaccine strategy. In this study, we compared the antigenicity of recombinant envelope glycoproteins derived from three primary isolates (PI) (HIV-1(BX08), HIV-1(CHA), and HIV-1(133)) and two TCLA viruses (HIV-1(HXB2) and HIV-1(MN)) produced using the Semliki Forest virus (SFV) system. This analysis was performed by radioimmunoprecipitation assays and flow cytometry. The results suggest that the SFV produces envelope glycoproteins with features in common with the envelopes found in naturally occurring virions. In particular, the PI envelopes had weak heterogeneous antigenic properties. However, the cytometric analysis also showed that there was less envelope glycoprotein on the cell surface for the PI envelopes than for those of TCLA viruses, suggesting differences in their intracellular trafficking. The immunogenic properties of the various envelope glycoproteins were evaluated in mice using recombinant SFV particles as vaccine vectors. The PI envelopes were less immunogenic than the TCLA envelopes, probably due to both their low antigenicity and cell surface expression level. Thus, it may be difficult to design an effective vaccine based on native recombinant PI envelopes.

Adaptation, Physiological↗
PubMed1975

Multiple sclerosis and parainfluenza 1 virus. History of the isolation of the virus and expression of phenotypic differences between the isolated virus and Sendai virus.

54 cultures were established from brain tissue obtained 2-3 hrs after death from 1 case of multiple sclerosis and 30 cultures from another case. Following fusion with indicator cells in the presence of lysolecithin, a parainfluenza type 1 virus (6/94 virus) was isolated from cultures representing one plaque area in the first case and one plaque area in the second case. A cell line chronically infected with the 6/94 virus has been maintained for more than 100 passages in vitro. A close relationship to the Sendai Hemagglutinating Virus of Japan (HVJ) is indicated from RNA-RNA hybridization and the patterns of electrophoretic mobilities of viral polypeptides. Conversely, differences in optima for growth-requirement temperatures, hemolytic activity and the capability to fuse mammalian cells, distinguishes 6/94 virus and HVJ as distinct phenotypic entities of a closely related genotype.

Adult↗
PubMed1986

Equine herpesvirus genomes: heterogeneity of naturally occurring type 4 isolates and of a type 1 isolate after heterologous cell passage.

The restriction endonuclease DNA fingerprints of 20 low passage, epidemiologically unrelated isolates of equine herpesvirus 4 (equine rhinopneumonitis virus) showed considerable heterogeneity in certain fragments, the positions of which were assigned to quite restricted positions on the 141 kilobase (kb) genome. We note that the heterogeneity observed in the restriction endonuclease DNA fingerprints of EHV 1 (equine abortion virus) and of pseudorabies virus also tend to map to these same restricted regions. The restriction endonuclease DNA fingerprints of an EHV 1 strain was invariant using low (less than 1) multiplicity of infection during 20 passages in equine cells but when adapted to hamster cells developed an approximately 0.8 kb deletion in the unique short region of the genome between 8 and 11 passages.

Animals↗