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1.
The antibiotic resistance patterns of fecal streptococci and fecal coliforms isolated from domestic wastewater and animal feces were determined using a battery of antibiotics (amoxicillin, ampicillin, cephalothin, chlortetracycline, oxytetracycline, tetracycline, erythromycin, streptomycin, and vancomycin) at four concentrations each. The sources of animal feces included wild birds, cattle, chickens, dogs, pigs, and raccoons. Antibiotic resistance patterns of fecal streptococci and fecal coliforms from known sources were grouped into two separate databases, and discriminant analysis of these patterns was used to establish the relationship between the antibiotic resistance patterns and the bacterial source. The fecal streptococcus and fecal coliform databases classified isolates from known sources with similar accuracies. The average rate of correct classification for the fecal streptococcus database was 62.3%, and that for the fecal coliform database was 63.9%. The sources of fecal streptococci and fecal coliforms isolated from surface waters were identified by discriminant analysis of their antibiotic resistance patterns. Both databases identified the source of indicator bacteria isolated from surface waters directly impacted by septic tank discharges as human. At sample sites selected for relatively low anthropogenic impact, the dominant sources of indicator bacteria were identified as various animals. The antibiotic resistance analysis technique promises to be a useful tool in assessing sources of fecal contamination in subtropical waters, such as those in Florida. 相似文献
2.
An interesting class of compounds of natural origin is dihydrophenanthrene dimers, which are characterized by a series of remarkable biological properties. Considering the hypothesis that each dimer is obtained through a biosynthetic mechanism that involves the coupling of the corresponding radicals of the single dihydrophenanthrene unit, we identified 29 dihydrophenanthrenes. Of these dihydrophenanthrenes, 11 were new compounds that could be isolated from 10 different plant species; 11 had already been identified, but not yet isolated in the 17 different plant species from which the corresponding dimers had been isolated; and 7 were known and had been isolated in the same plant sources of the corresponding dimers. A targeted analysis of several natural extracts from specific plant sources would allow the identification of known or new molecules with potential and/or specific biological activities and, in a final analysis, would confirm the relative biosynthetic mechanism. 相似文献
3.
A simple apparatus was developed to allow 12 petri plates to be poured simultaneously by hand. It was used when screening
bacterial isolates from sewage and dog feces for their ability to detect phages from these sources. This was done to assess
the ease with which source-specific phage hosts can be isolated from these sources of fecal pollution. Host bacteria that
consistently detected phages from sewage were easily isolated from sewage. These bacterial isolates did not detect phages
from dog feces. Host bacteria were not isolated from dog feces even after screening hundreds of colonies from fecal samples
from six dogs. Journal of Industrial Microbiology & Biotechnology (2000) 24, 124–126.
Received 06 July 1999/ Accepted in revised form 05 November 1999 相似文献
4.
5.
Begum YA Talukder KA Nair GB Khan SI Svennerholm AM Sack RB Qadri F 《Canadian journal of microbiology》2007,53(1):19-26
Enterotoxigenic Escherichia coli (ETEC) is a common cause of bacterial infection leading to acute watery diarrhea in infants and young children. Although the prevalence of ETEC is high in Bangladesh and infections can be spread through food and contaminated water, limited information is available about ETEC in the surface water. We carried out studies to isolate ETEC from surface water samples from ponds, rivers, and a lake from a site close to field areas known to have a high incidence of diarrhea in Dhaka, Bangladesh, and Matlab, Bangladesh. ETEC strains isolated from the water sources were compared with ETEC strains isolated from patients with diarrhea at two hospitals in these areas. ETEC were isolated from 30% (45 of 150) of the samples from the surface water sources and 19% (518 of 2700) of the clinical specimens. One hundred ETEC strains isolated from patients with similar phenotypes as the environmental strains were compared for phenotypic and genotypic properties. The most common O serogroups on ETEC were O6, O25, O78, O115, and O126 in both types of strains. Pulsed-field gel electrophoresis analyses of the ETEC strains showed that multiple clones of ETEC were present within each colonization factor type and that some clones detected in the environment were also isolated from the stools of patients. The strains showed multiple and similar antibiotic resistance patterns. This study shows that ETEC is prevalent in surface water sources in Bangladesh suggesting a possible reason for the endemicity of this pathogen in Bangladesh. 相似文献
6.
I Bernier A Dautigny B E Glatthaar W Lergier J Jollès D Gillessen P Jollès 《Biochimica et biophysica acta》1980,626(1):188-196
alpha 1-Microglobulin was purified from normal and pathological urines. Significant differences were found in the amino acid compositions of the alpha 1-microglobulin isolated from these two sources. In addition electrofocusing of alpha 1-microglobulin from normal urine gave rise to two peaks of equal intensity with rather acidic isoelectric points (3.8 and 4.2), whilst alpha 1-microglobulin from pathological urine showed two peaks in a 1:5 ratio with less acidic isoelectric points (4.2 and 4.7). Further charge heterogeneity was also observed in the second peaks from both sources. The sugar compositions were also established, as well as the N-terminal sequences of the alpha 1-microglobulin of both peaks isolated from normal and pathological urines. 相似文献
7.
Iakovlev AG Sheenkov NV Iartseva NN Cherkasov SV Bukharin OV 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》2001,(4):123-124
Persistence factors in 70 B. abortus strains isolated from different sources were studied. Depending on the source of the isolation of B. abortus, the spread of their antilysozyme, anticomplementary, antiintercidal activity was determined and intraspecific differences in the manifestation of these signs were established. The highest spread and manifestation of persistence factors was registered in B. abortus populations isolated from brucellosis patients and from cattle. 相似文献
8.
Koichi Ogata Masahiro Ohsugi Minoru Tomita Tatsurokuro Tochikura 《Bioscience, biotechnology, and biochemistry》2013,77(3):364-369
Metabolites from salicylic acid by microorganisms were investigated. About eighty strains of bacteria which were able to utilize salicylic acid as a sole source of carbon were isolated from soil and other natural sources.Among these bacteria, several strains produced a large amount of keto acids in the culture fluid during the cultivation. The acid was isolated from the culture fluid of strain K 102 in crystalline form. The crystal was identified as α-ketoglutaric acid by physicochemical methods. From the taxonomical studies, the isolated bacterial strains K 102 and K 362 were assumed to be Pseudomonas sp. 相似文献
9.
Differences in substrate specificities of monoamine oxidase A from human liver and placenta. 总被引:1,自引:0,他引:1
A K Tan W Weyler J I Salach T P Singer 《Biochemical and biophysical research communications》1991,181(3):1084-1088
The substrate specificities of monoamine oxidase (MAO) A isolated from human placenta and of human liver expressed in yeast have been compared in homogeneous preparations with respect to Vmax and Km values for natural and synthetic substrates and Ki values for competitive inhibitors. MAO A from these two sources is known to differ in at least 5 amino acid residues. While the Km and Ki values were found to be nearly identical in the enzymes from these two sources, the Vmax differed significantly on bulky synthetic substrates. 相似文献
10.
It was found in vitro that desoxycholic, cholic, glycocholic and choleinic acids inhibited the growth and development of staphylococci. The staphylococci isolated from bile were more resistant to the bacteriostatic and bactericidal effect of bile acids than the microorganisms isolated from other sources not containing cholates. Under the effect of these substances the activity of some antibiotics especially those from the group of aminoglycosides markedly increased. 相似文献
11.
Katja E. Hill J.C. Fry A.J. Weightman M.J. Day D.J. Bradley B. Cousland 《Letters in applied microbiology》1995,20(5):317-322
The first observation of plasmid retrotransfer by plasmids isolated from environmental sources is reported. A high incidence of retrotransferring ability amongst plasmids isolated from epilithic bacteria was found; some of these plasmids retrotransferred an IncQ plasmid at very high frequencies. Despite the broad host-range of the majority of the plasmids, only five out of 12 could be assigned to an incompatibility group by DNA hybridization. All five were designated IncP1; this revealed a limitation of probes derived from clinical sources for use with environmental isolates. Incompatibility testing by plate mating suggested that four additional plasmids displayed varying, albeit lower, degrees of incompatibility to the IncP1 plasmid RP1. 相似文献
12.
Biologic properties of mesenchymal stem cells derived from bone marrow and adipose tissue 总被引:15,自引:0,他引:15
Izadpanah R Trygg C Patel B Kriedt C Dufour J Gimble JM Bunnell BA 《Journal of cellular biochemistry》2006,99(5):1285-1297
The biologic characteristics of mesenchymal stem cells (MSCs) isolated from two distinct tissues, bone marrow and adipose tissue were evaluated in these studies. MSCs derived from human and non-human primate (rhesus monkey) tissue sources were compared. The data indicate that MSCs isolated from rhesus bone marrow (rBMSCs) and human adipose tissue (hASCs) had more similar biologic properties than MSCs of rhesus adipose tissue (rASCs) and human bone marrow MSCs (hBMSCs). Analyses of in vitro growth kinetics revealed shorter doubling time for rBMSCs and hASCs. rBMSCs and hASCs underwent significantly more population doublings than the other MSCs. MSCs from all sources showed a marked decrease in telomerase activity over extended culture; however, they maintained their mean telomere length. All of the MSCs expressed embryonic stem cell markers, Oct-4, Rex-1, and Sox-2 for at least 10 passages. Early populations of MSCs types showed similar multilineage differentiation capability. However, only the rBMSCs and hASCs retain greater differentiation efficiency at higher passages. Overall in vitro characterization of MSCs from these two species and tissue sources revealed a high level of common biologic properties. However, the results demonstrate clear biologic distinctions, as well. 相似文献
13.
Lin HY Chiu HL Lan YH Tzeng CY Lee TH Lee CK Shao YY Chen CR Chang CI Kuo YH 《化学与生物多样性》2011,8(9):1701-1708
Four new lactone chlorins, ficuschlorins A – D ( 1 – 4 , resp.), and six known pheophytins were isolated from the leaves of Ficus microcarpa. The structures of these compounds were determined by 1D‐ and 2D‐NMR spectroscopy, and other techniques. New natural pheophytins were rarely obtained. In the past ten years, only three new pheophytins were isolated from natural sources. 相似文献
14.
Fifty-two cultures of Prototheca spp. isolated from water and 7 isolates received from a culture collection were tested for their ability to assimilate carbon and nitrogen sources. Based upon these findings and on micromorphological features of the isolates a rapid method allowing differentiation of Prototheca spp. in culture is presented. 相似文献
15.
A wide variety of novel small-molecule natural products has recently been reported. These compounds were isolated from marine and terrestrial sources, and from a variety of animals, plants and microorganisms. With the breadth of diversity represented in these bioactive small molecules, the future of natural product drug discovery looks bright. 相似文献
16.
Warda M Gouda EM Toida T Chi L Linhardt RJ 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2003,136(4):357-365
Heparin, a heterogeneous anionic polysaccharide, is the glycosaminoglycan (GAG) used clinically an anticoagulant. This anticoagulant activity is primarily derived from its binding to the serine protease inhibitor antithrombin III, a potent inhibitor of thrombin (factor IIa) and factor Xa. Heparin is a complex natural product and its in vitro synthesis is not yet possible due to the difficulty of organizing the many biosynthetic enzymes required for its synthesis. The principle natural sources for heparin include porcine intestine and bovine lung. These two sources pose concerns for religious and health reasons, respectively. To circumvent these concerns, GAG from the intestinal tissue of one humped camel was isolated. Chemical characterization of this newly isolated GAG and spectroscopic analysis by 1D and 2D 1H-NMR were undertaken. Unsaturated disaccharide compositional analysis was performed on the enzymatically depolymerized GAG and the molecular weight of the isolated GAG was determined by gradient polyacrylamide gel electrophoresis. Anticoagulant activity of the newly isolated GAG was tested by using an anti-factor Xa assay. The results of these studies suggest that the GAG from one humped camel intestine is a mixture of heparin and heparan sulfate and represents an alternative source of heparin. 相似文献
17.
Kumiko Matsuura Mitsuhiro Ishikura Takashi Nakayama Sumiyo Hasegawa Osayuki Morita Kouji Katori Hisao Uetake 《Microbiology and immunology》1993,37(4):305-310
In order to clarify the source of reovirus pollution in river water, comparative surveys have been carried out between reovirus isolates from river water and those from sewage, human or animal, by making use of the analysis of genomic RNA-migration pattern of reovirus in polyacrylamide gel electrophoresis (electropherotype). The strains of reovirus serotype 1 and 2 isolated from river water were classified into 3 and 9 electropherotypes, respectively, and 8 out of these 12 types were also found among strains isolated from sewage or human. When the monthly distribution of the river isolates classified by electropherotypes was compared with that of the sewage isolates, there were cases in which strains of the same electropherotype were simultaneously isolated from both sources. The electropherotypes of 3 isolates from pig and field rodents were different from those of the other isolates. The electropherotype of an oyster isolate coincided with that of some of the isolates from humans and river water. These results indicate that the major sources of reoviruses polluting river water may be the human excretion. 相似文献
18.
The lipids isolated from different animal tissues have been studied qualitatively, by TLC, for the occurrence of the ungulic acid fraction. This fraction was found in considerable amounts only in epidermal tissues and its keratinized derivatives. In the present study it was isolated from human keratinous epidermis, hair, and nails, pig bristles, wool, and feathers. The analytical results indicated that a lipid fraction from all of these sources contained ceramide, galactose, galactosamine, sulfate, and sialic acid in equimolar amounts, and that the fractions were similar to the ungulic acid isolated earlier from a horse's hoof. 相似文献
19.
John J. Eppig Michael L. Steckman 《In vitro cellular & developmental biology. Plant》1976,12(3):173-179
Summary The purpose of these experiments was to determine which exogenous energy sources are suitable for isolated follicle cell-free
oocytes from the frog,Xenopus laevis. In order to compare prospective energy sources, follicle cell-free oocytes from 0.4 to 1.3 mm in diameter were incubated
in a 1 mM concentration of each of a variety of energy sources and scored daily for the maintenance of morphological characteristics.
Vitellogenic oocytes placed in succinate or fumarate deteriorated at the same time as those in saline alone. Oocytes incubated
in oxaloacetate (OAA) appeared to remain in the best morphological condition, followed by oocytes maintained in pyruvate or
glucose. Fully grown oocytes were tested at various times of incubation for their ability to respond to progesterone by undergoing
germinal vesicle breakdown. These experiments showed that oocytes placed in OAA or pyruvate retained the ability to respond
to progesterone longer than those in the other energy sources. Increased respiratory rates were stimulated in isolated oocyte
mitochondria by succinate as well as pyruvate and OAA. However, oocytes incubated in labelled pyruvate evolved 80 to 140 times
as much labelled CO2 as oocytes incubated in labelled glucose or succinate. In addition, it was found that the rate of uptake of pyruvate is 20
to 25 times greater than the rate of uptake of glucose or succinate. It is concluded from these experiments that OAA and pyruvate
are the most effective exogenous energy sources for the in vitro maintenance ofXenopus oocytes. One possible explanation for the ineffectiveness of glucose or succinate as exogenous energy sources is a restriction
in their uptake into the oocytes.
Research supported by grants 10179 from the Research Foundation of the City University of New York and BMS 74-18790 from the
National Science Foundation. 相似文献
20.
Stem cell therapy is in constant need of new cell sources to conceive regenerative medicine approaches for diseases that are still without therapy. Scientists drew the attention toward amniotic membrane and amniotic fluid stem cells, since these sources possess many advantages: first of all as cells can be extracted from discarded foetal material it is inexpensive, secondly abundant stem cells can be obtained and finally, these stem cell sources are free from ethical considerations. Many studies have demonstrated the differentiation potential in vitro and in vivo toward mesenchymal and non-mesenchymal cell types; in addition the immune-modulatory properties make these cells a good candidate for allo- and xenotransplantation. This review offers an overview on markers characterisation and on the latest findings in pre-clinical or clinical setting of the stem cell populations isolated from these sources. 相似文献