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1.
Ethnobotanical study of plants revealed that the local community of Ghalegy, District Swat, invariably uses 126 species of 59 families for various purposes. Based on their traditional local uses, fifty- seven species ( 4512%) were classified as medicinal, forty-seven as fire wood ( 3713%) , forty- five as forage ( 3517%) , twenty- eight as honey bee species ( 2212%) , twenty- seven as vegetable species ( 2114%) , 25 as edible fruits ( 14 wild and 11cultivated) , thirteen as timber wood ( 1013%) , twelve as ornamental ( 91 5%) , eleven as furniture wood, ten as shelter and thatch makers ( 719%) , ten as fencing ( 719%) , five as poisonous ( 4%) , four as religiousPsuperstitious species, three species used in making hand sticks and wooden tools ( 21 4%) , three as utensil cleaner species ( 214%) , three as evil repellent and one as fish poisoning species. The area is in plant resources and traditional knowledge but it needs ecological management for its sustainability.  相似文献   

2.
The polymerase chain reaction (PCR) method has been employed to amplify a chlamydial genome encoding four variable segments of the major outer membrane protein and genotyping of different Chlamydia trachomatis serovars was successfully achieved by means of restriction fragment length polymorphism (RFLP) analysis and sequencing of amplified DNA. These methods were applied to identify the serotypes of C. trachomatis in endocervical specimens obtained from asymptomatic pregnant Japanese women at 28-30 weeks of gestation. Among the 218 specimens, 207 were serotyped 43 (19.3%) as serovar D, 53 (24.3%) as E, 24 (11.0%) as F, 39 (17.9%) as G, 15 (6. 9%) as H, 15 (6.9%) as I, five (2.3%) as J, nine (4.1%) as K and four (1.8%) as mixed. Among the 11 unclassified strains by RFLP, six (2.8%) were identified as serovar B variants and five (2.3%) were identified as D/IC-Cal-8. It was suggested that variants of endemic trachoma serovars also have affinity for the urogenital tract of Japanese pregnant women.  相似文献   

3.
Solid-state (13)C NMR measurements of intact soybean leaves labeled by (13)CO(2) (at subambient concentrations) show that excess glycine from the photorespiratory C(2) cycle (i.e. glycine not part of the production of glycerate in support of photosynthesis) is either fully decarboxylated or inserted as (13)C-labeled glycyl residues in proteins. This (13)C incorporation in leaf protein, which is uniformly (15)N labeled by (15)NH(4)(15)NO(3), occurs as soon as 2 min after the start of (13)CO(2) labeling. In those leaves with lower levels of available nitrogen (as measured by leaf nitrate and glutamine-glutamate concentrations), the excess glycine is used primarily as glycyl residues in protein.  相似文献   

4.
Forty-one isolates of moderately halophilic bacteria were isolated from fermented fish (pla-ra) in Thailand. On the basis of their phenotypic and chemotaxonomic characteristics, DNA-DNA relatedness and 16S rRNA gene sequences analyses, they were divided into six groups. The isolates in Group I to V were Gram-positive rod-shaped bacteria. They contained meso-diaminopimelic acid in the cell-wall peptidoglycan and menaquinone with seven isoprene units (MK-7). An isolate in Group VI was a Gram-negative rod-shaped bacterium. The DNA G+C contents of tested strains ranged from 36.5-63 mol%. Ten strains (Group I) were identified as Virgibacillus dokdonensis, 13 isolates (Group II) as V. halodenitrificans, 14 isolates (Group III) as V. marismortui, 1 isolate (Group IV) as Virgibacillus sp., 2 isolates (Group V) as Bacillus vietnamnensis, and 1 isolate (Group VI) as Chromohalobacter salexigens. Isolate MS3-4 in Group IV was closely related to V. carmonensis KCTC 3819(T) (95.9%). This strain contained anteiso-C(15:0) (55.8%) and anteiso-C(17:0) (17.7%) as major cellular fatty acids and had phosphatidylglycerol, diphosphatidylglycerol and an unidentified glycolipid as polar lipids. The DNA G+C content of MS3-4 was 38.0 mol%. The strain from Group IV is proposed as Virgibacillus siamensis sp. nov. and MS3-4(T) is the type strain (JCM 15395(T) =PCU 312(T) =TISTR 1957(T)).  相似文献   

5.
L-lactide was polymerized as concentrated solution in chlorobenzene with Bi(OAc)3 as initiator. When tetra(ethylene glycol) was added as co-initiator (CoI), telechelic polylactides having two CH-OH end groups were obtained. With 1,1,1-tri(hydroxy methyl)propane (THMP) as co-initiator, three-armed stars having three CH-OH end groups were formed. Analogously, tetrafunctional star-shaped poly(L-lactide)s were obtained with pentaerythritol as co-initiator. The chain lengths were varied via the monomer/CoI ratio. Time-conversion curves proved that Bi(OAc)3 is slightly less reactive as initiator than tin(II) 2-ethylhexanoate. However, bismuth acetate (or other carboxylates) have a particularly low toxicity as documented in the literature and by numerous Bi3+-containing pharmaceutical products.  相似文献   

6.
An attempt was made to use a simple procedure to obtain (R)- and (S)-2-aminobutanoic acids [(R)- and (S)-1] which are non-proteinogenic alpha-amino acids and are useful as chiral reagents in asymmetric syntheses. Compound (RS)-1 p-toluenesulfonate [(RS)-2], which is known to exist as a conglomerate, was optically resolved by replacing crystallization with (R)- and (S)-methionine p-toluenesulfonate [(R)- and (S)-3] as optically active co-solutes. When (S)-3 was employed as the co-solute, (R)-2 was preferentially crystallized from a supersaturated solution of (RS)-2 in 1-propanol, as was (S)-2 in the presence of (R)-3. (R)- and (S)-2 recrystallized from 1-propanol were treated with triethylamine in methanol to give (R)- and (S)-1 in optically pure forms.  相似文献   

7.
Cholesterol oxidase (ChOx) has been covalently immobilized onto two-dimensional self-assembled monolayer (SAM) of N-(2-aminoethyl)-3-aminopropyl-trimethoxysilane (AEAPTS) deposited on the indium-tin oxide (ITO) coated glass plates using N-ethyl-N'-(3-dimethylaminopropyl) carbodiimide and N-hydroxysuccinimide (EDC/NHS) chemistry. These ChO x/AEAPTS/ITO bioelectrodes are characterized using contact angle (CA) measurements, UV-visible spectroscopy, atomic force microscopy (AFM), electrochemical impedance technique, and Fourier transform infrared (FT-IR) technique. The covalently immobilized ChOx-modified AEAPTS bioelectrodes are used for the estimation of cholesterol in solution using UV-visible technique. These cholesterol sensing bioelectrodes show linearity as 50 to 500 mg/dl for cholesterol solution, detection limit as 25mg/dl, sensitivity as 4.499 x 10(-5) Abs (mg/dl)(-1), K(m) value as 58.137 mg/dl (1.5mM), apparent enzyme activity as 1.81 x 10(-3) U cm(-2), shelf life of approximately 10 weeks, and electrode reusability as 10 times.  相似文献   

8.
Specific Inhibitors of Ammonia Oxidation in Nitrosomonas   总被引:22,自引:6,他引:16       下载免费PDF全文
The following compounds or treatments have been shown to inhibit the oxidation of ammonia, but not the oxidation of hydroxylamine in cells of Nitrosomonas: (i) metal-binding agents such as allylthiourea or potassium cyanide; (ii) compounds such as SKF 525 which interact with cytochrome P-450 of mammalian microsomes; (iii) carbon monoxide; (iv) inhibitors of catalase, peroxidase, and amine oxidases such as thiosemicarbazide, ethylxanthate, and iproniazid, respectively; (v) uncouplers of oxidative phosphorylation such as m-chlorocarbonylcyanidephenylhydrazone; (vi) electron acceptors such as phenazine methosulfate; (vii) compounds such as methanol or N(2)O which react with free radicals; and (viii) illumination with 420 lux (5,000 foot candles) of light.  相似文献   

9.
A series of (E)-5-(1-alkenyl)-dUTPs as well as 5-vinyl-and (Z)-5-(1-propenyl)-dUTP have been synthesized to study steric requirements in DNA polymerase reactions. Experiments were carried out in E. coli DNA polymerase I Klenow fragment enzyme system. Substrates were characterized by KM and Vmax-values, initial incorporation rates as well as by total extent of incorporation of the analogues into poly(dA-dT) as a template-primer. Incorporation of the analogues could be best correlated with Vmax-values as well as the very similar initial incorporation rate values. Reactivity (Vmax/KM) showed no correlation with the extent of incorporation. 5-Vinyl-dUTP proved to be as good a substrate of the enzyme as dTTP, whereas (E)-5-(1-heptenyl)-and (E)-5-(1-octenyl)-dUTPs were very poor substrates, their incorporation was strongly limited and they also proved to be very efficient inhibitors of DNA replication, as shown by Ki-values. Substrate specificity of the Klenow enzyme can be explained by the steric hindrance of C-5 substituent, by the "orientational steric substituent effect" concept.  相似文献   

10.
Bombesin-like peptides as well as receptor-independent activators were tested for their effect on gastrin release from acutely dispersed rat gastric G-cells. The amphibian peptide bombesin as well as its mammalian analogues neuromedin B and neuromedin C stimulated gastrin release. Maximal responses were achieved with 10(-9) M bombesin (191.0 +/- 16.8% of basal release), 10(-8) M neuromedin C(205.9 +/- 17.6%) and 10(-7) M neuromedin B (162.2 +/- 10.4%), respectively. The phorbol ester 12-O-tetradecanoyl-phorbol 13-acetate (TPA) and the synthetic diacylglycerol analogue 1-oleoyl-2-acetyl-sn-glycerol (OAG) are receptor-independent activators of the protein kinase C. Both TPA (10(-6) M) and OAG (10(-5) M) stimulated gastrin release to 214.0 +/- 29.3% and 198.2 +/- 20.8% of basal, respectively. Calcium ionophore A23187 (10(-5) M) was the most effective stimulant tested (364.7 +/- 39.6%). Its effect was reversed by the calmodulin antagonist W 7 (10(-6)-10(-5) M). Finally, forskolin (10(-5) M), a direct activator of cAMP-formation, as well as the cAMP-analogue dbcAMP (10(-3) M) induced gastrin release. IN conclusion, neuromedin B is less potent and less effective than neuromedin C and bombesin in stimulating rat gastric G-cells. In addition, gastrin release is activated by calcium- and phospholipid-dependent as well as by cAMP-induced cellular signal transduction mechanisms.  相似文献   

11.
Alternatively spliced human glutaredoxin (Grx1(as)) cDNA was isolated from a neutrophil cDNA library, using a (32)P-labeled human glutaredoxin (Grx1) cDNA probe under non-stringent conditions. The sequence of Grx1(as) cDNA indicated that the open reading frame of the gene was identical to the open reading frame of the previously reported first human glutaredoxin (Grx1) cDNA, but the 3'-untranslated region of Grx1(as) was not homologous to Grx1 cDNA. Northern blot and RT-PCR analyses showed Grx1(as) mRNA was expressed in normal human neutrophils and transformed cells including U937, HL-60, THP, and Jurkat cells. Cloning and sequencing of the genomic gene corresponding to Grx1(as) cDNA showed that two different glutaredoxin cDNAs (Grx1(as) and Grx1) were generated from the same genomic gene via alternative splicing. Origination of Grx1(as) and Grx1 from the same gene was confirmed by chromosomal localization of the Grx1(as) gene to chromosome 5q13, the same location where the Grx1 gene was localized previously. During screening of the Grx1(as) genomic gene, two additional glutaredoxin pseudogenes were also isolated. Surprisingly, these pseudogenes contained 3'-untranslated regions that were nearly identical to the 3'-untranslated regions of Grx1(as,) not Grx1, cDNA. Because 3'-untranslated regions may be important in stabilizing mRNAs, the effect of the two 3'-untranslated regions of Grx1 and Grx1(as) on mRNA stability was investigated using luciferase reporter vectors with the 3'-untranslated regions. Luciferase activity was 2.6-fold greater in cells transfected with the reporter vector containing the 3'-untranslated region of Grx1(as) cDNA compared with the 3'-untranslated region of Grx1 cDNA. These data indicate that Grx1(as) cDNA is an alternatively spliced human Grx1 cDNA and that the Grx1(as) 3'-untranslated region may have a role in stabilizing mRNA.  相似文献   

12.
ABSTRACT: BACKGROUND: Diagnosis of amoebic liver abscess (ALA) in patients on anti-amoebic drugs is difficult. There is scanty data on this issue using Entamoeba histolytica (E. histolytica) lectin antigen and polymerase chain reaction (PCR). We studied lectin antigen, PCR, and IgG antibody in liver abscess patients. Liver aspirate of 200 patients, of which 170 had anti-amoebic drug prior to drainage, was tested for E. histolytica lectin antigen by ELISA, PCR, bacterial culture, and serum IgG antibody by ELISA. Classification of abscesses was based on result of anti-amoebic IgG antibody and bacterial culture, E. histolytica PCR and bacterial culture, and E. histolytica lectin antigen and bacterial culture was evaluated. FINDINGS: Using anti-amoebic IgG antibody and bacterial culture, 136/200 (68.0%) were classified as ALA, 12/200 (6.0%) as pyogenic liver abscess (PLA), 29/200 (14.5%) as mixed infection, and 23/200 (11.5%) remained unclassified. Using amoebic PCR and bacterial culture 151/200 (75.5%) were classified as ALA, 25/200 (12.5%) as PLA, 16/200 (8.0%) as mixed infection, and 8/200 (4.0%) remained unclassified. With E. histolytica lectin antigen and bacterial culture, 22/200 (11.0%) patients were classified as ALA, 39/200 (19.5%) as PLA, 2/200 (1.0%) as mixed infection, and 137/200 (68.5%) remained unclassified. CONCLUSIONS: E. histolytica lectin antigen was not suitable for classification of patients who had prior anti-amoebic treatment. However, PCR may be used as alternative test to anti-amoebic antibody in diagnosis of ALA.  相似文献   

13.
Interruption of the (I)n strand of (I)n.(C)n by unpaired bases [(U)] yielded mismatched analogues, (Ix,U)n.(C)n which were still effective as inducers of interferon, provided the I:U ratio (x) was equal or greater than 10. In highly sensitive interferon-induction systems such as primary rabbit kidney cells and human skin fibroblasts superinduced with cycloheximide and actinomycin D, (I10,U)n.(C)n and (I50,U)n.(C)n proved nearly as active as (I)n.(C)n. By virtue of their increased susceptibility to degradation by nucleases, (Ix,U)n.(C)n complexes with 10 less than or equal to x less than or equal to 50 may be expected not to persist as long in biological fluids as (I)n.(C)n, hence to induce fewer side effects.  相似文献   

14.
Inorganic tripolyphosphate (PPP(i)) and pyrophosphate (PP(i)) were examined as potential phosphate donors for human deoxynucleoside kinase (dCK), deoxyguanosine kinase (dGK), cytosolic thymidine kinase (TK1), mitochondrial TK2, and the deoxynucleoside kinase (dNK) from Drosophila melanogaster. PPP(i) proved to be a good phosphate donor for dGK, as well as for dCK with dCyd, but not dAdo, as acceptor substrate, illustrating also the dependence of donor properties on acceptor. Products of phosphorylation were shown to be 5(')-phosphates. In striking contrast to ATP, the phosphorylation reaction follows strict Michaelis-Menten kinetics, with K(m) values of 74 and 92 microM for dCK and dGK, respectively, and V(max) values 40-50% that for ATP. With the other three enzymes, as well as for dCK with dAdo as acceptor, no, or only low levels (相似文献   

15.
Prior exposure of respiratory epithelial cells to an aqueous-trapped solution of diesel exhaust (DE(as)) enhances the susceptibility to influenza infections. Here, we examined the effect of DE(as) on the Toll-like receptor 3 (TLR3) pathway, which is responsible for the recognition of and response to viruses and double-stranded RNA. Flow cytometric and confocal microscopy analyses showed that TLR3 is predominantly expressed in the cytoplasm of respiratory epithelial cells. To examine the effect of DE on TLR3 expression and function, differentiated human bronchial or nasal epithelial cells as well as A549 cells were exposed to DE(as) and then infected with influenza A or treated with polyriboinosinic acid-polyribocytidylic acid [poly(I:C)], a synthetic form of double-stranded RNA. Exposure to DE(as) before infection with influenza or stimulation with poly(I:C) significantly upregulated the expression of TLR3. Additionally, preexposure to DE(as) significantly increased the poly(I:C)-induced expression of IL-6. Overexpression of a dominant-negative mutant form of TNF receptor-associated factor 6 reversed the effects of DE(as) on poly(I:C)-induced IL-6 expression, suggesting that the response was TLR3 dependent. Similarly, preexposure to DE(as) significantly increased nuclear levels of interferon regulatory factor 3 and the expression of IFN-beta in response to poly(I:C). Pretreatment with wortmannin, a specific inhibitor of phosphatidylinositol 3-kinase, was able to abate the effect of DE(as) on poly(I:C)-induced IFN-beta expression. Together, these results indicate that exposure of respiratory epithelial cells to DE(as) could potentially alter the response to viral infections by increasing the expression and function of TLR3.  相似文献   

16.
The non-covalent DNA interaction of the anticancer drug ellipticine (Scheme I, 1a) as well as an indolo[2,3-b]-quinoxaline derivative (Scheme I, 3b) with a dimethylaminoethyl side chain has been studied by light absorption, linear dichroism (LD) and fluorescence. Compound 3b (Scheme I) has antitumorigenic as well as antiviral activity. Both compounds bind to DNA or synthetic polynucleotides such as poly(dA-dT).(dA-dT) and poly(dG-dC).(dG-dC) by intercalation. In contrast to ellipticine, compound 3b (Scheme I) exhibits a significant binding specificity for alternating AT sequences. Its fluorescence is strongly enhanced in AT sequences and quenched in GC sequences. Fluorescence titrations evaluated as Scatchard plots show that both ellipticine and compound 3b (Scheme I) bind to the nucleic acids according to a non-cooperative neighbor exclusion model.  相似文献   

17.
A series of azaflavone derivatives and analogues were prepared and evaluated for their affinity to the benzodiazepine binding site of the GABA(A) receptor, and compared to their flavone counterparts. Three of the compounds, the azaflavones 9 and 12 as well as the new flavone 13, were also assayed on GABA(A) receptor subtypes (alpha(1)beta(3)gamma(2s), alpha(2)beta(3)gamma(2s), alpha(4)beta(3)gamma(2s) and alpha(5)beta(3)gamma(2s)), displaying nanomolar affinities as well as selectivity for alpha1- versus alpha2- and alpha3-containing receptors by a factor of between 14 and 26.  相似文献   

18.
19.
The stimulating effect of copper addition on the reduction rate of nitrous oxide (N(2)O) to dinitrogen (N(2)) in the presence of sulfide was investigated in batch experiments (pH 7.0; 55 degrees C). N(2)O was dosed either directly as a gas to the headspace of the bottles or formed as intermediate during the denitrification of nitrite in Fe(II)EDTA(2-)-containing medium and nitrate in Fe(II)EDTA(2-)-free medium. Sulfide was either dosed externally or generated from endogenous sulfur sources during anaerobic incubation of the sludge. In the presence of sulfide (from 15 microM to 1mM), heterotrophic denitrification using ethanol as electron donor was incomplete, i.e., N(2)O accumulated instead of N(2) or was transiently formed. Copper addition (60 microM) rapidly stimulated the reduction of N(2)O to N(2). Zinc addition (60 microM) did not have a similar strong stimulating effect as observed for copper and the N(2)O reduction rate was not stimulated at all upon supply of FeCl(3) (2 mM). Thus, a copper deficiency for N(2)O reduction is most likely developed in the presence of sulfide. It is suggested that sulfide induces this deficiency as it readily precipitates as copper sulfide and thus scavenges copper in the medium or that sulfide inactivates the N(2)OR reductase as it sequesters the copper of this metalloenzyme.  相似文献   

20.
Two granulosis viruses (GV) were tested as enhancers for the gypsy moth nuclear polyhedrosis virus (LdMNPV). Helicoverpa armigera (Hübner) CV (HaGV) had no detrimental effect upon larval growth and development, but in combination with LdMNPV it reduced both the LC50 and the LT50 for the NPV. In addition, the combination also adversely affected the growth and development of gypsy moth larvae. The LC50 of LdMNPV was reduced by as much as 300-fold (HaGV at 10(-2) dilution) and the LT50 was reduced by as much as 18% (HaGV at 10(-2) dilution). Spodoptera frugiperda (J. E. Smith) GV reduced the LC50 of LdMNPV by as much as 13-fold but had no effect upon the LT50.  相似文献   

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