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181.
Cranberry ( Vaccinium macrocarpon ) has been shown in clinical studies to reduce infections caused by Escherichia coli and other bacteria, and proanthocyanidins are believed to play a role. The ability of cranberry to inhibit the growth of opportunistic human fungal pathogens that cause oral, skin, respiratory, and systemic infections has not been well-studied. Fractions from whole cranberry fruit were screened for inhibition of five Candida species and Cryptococcus neoformans , a causative agent of fungal meningitis. Candida glabrata , Candida lusitaniae , Candida krusei , and Cryptococcus neoformans showed significant susceptibility to treatment with cranberry proanthocyanidin fractions in a broth microdilution assay, with minimum inhibitory concentrations as low as 1 μg/mL. MALDI-TOF MS analysis of subfractions detected epicatechin oligomers of up to 12 degrees of polymerization. Those containing larger oligomers caused the strongest inhibition. This study suggests that cranberry has potential as an antifungal agent.  相似文献   
182.
ABSTRACT:   Standard molecular techniques, such as sequencing and restriction fragment length polymorphism analysis after polymerase chain reaction (PCR) amplification are relatively complicated, and species identification can take a long time when using such techniques. We established a quick method, using PCR with species-specific TaqMan Minor Groove Binder (MGB) probes based on single nucleotide polymorphism (SNP) to distinguish the two eel species Anguilla japonica and Anguilla anguilla . This method can be used in processed products. Partial sequences of the mitochondrial 16S rRNA gene were compared between A. japonica and A. anguilla to design a primer pair common to both A. japonica and A. anguilla and probes specific to A. japonica and A. anguilla . Different fluorescence intensities were produced in two PCR microtubes each containing A. japonica - and A. anguilla -specific probes for one target sample. We observed the fluorescence intensity of PCR products in microtubes under ultraviolet transillumination, with similar results to those obtained by real-time PCR. Therefore, SNP-based PCR is a powerful tool for identifying materials of processed foods from either A. japonica or A. anguilla .  相似文献   
183.
Changes in the diet have been previously reported to alter the gut bacterial profile in several organisms, including shrimp. These shifts in microbial structure either promote beneficial effects to the host or cause diseases. Supplementation of 5‐aminolevulinic acid (5‐ALA), the precursor of tetrapyrroles, has been previously reported to enhance shrimp's immune response. To know whether 5‐ALA has effects on the gut bacterial structure in Pacific white shrimp (Litopenaeus vannamei), we investigated the bacterial communities in the intestine and stomach of L. vannamei using high‐throughput Illumina sequencing of 16S rRNA gene libraries. One week of 5‐ALA supplementation altered the bacterial community structure (beta diversity) in both tissues, as shown by the results of multi‐dimensional scaling (MDS) plots and analysis of similarities (ANOSIM). DESeq2 analysis revealed enrichment of differentially abundant taxa in the 5‐ALA group (e.g. Enhydrobacter and Oceaniovalibus) and control group (e.g. Tenacibaculum and Mycobacterium). Metagenomic predictions suggested that the control group had more KEGG pathways associated with ‘metabolism’ than the 5‐ALA group. This study suggests that 5‐ALA supplementation potentially promotes the formation of a beneficial bacterial community structure in shrimp. This is the first report on the effect of 5‐ALA supplementation on the bacterial community profile in any organism.  相似文献   
184.
A new continuous separation method was developed for the determination of five different tetracyclines (oxytetracycline, tetracycline, chlortetracycline, methacycline and doxycycline). A bioassay using minimum medium (mm) seeded with Bacillus subtilisatcc 6633 was carried out for the detection, with simple extraction from the agar block of the clear inhibition zone on the MM produced by the mixed tetracyclines. The extract was subjected to continuous identification by high performance liquid chromatography using a μ-Bondapack C18 column. The tetracyclines were separated at ambient temperature using a mobile phase of 0·01 M oxalic acid: acetonitrile: N,N-dimethylformamide (74:18:8, v/v/v) at a flow rate of 1·0 ml min−1. A variable-wavelength detector set at 355 nm and recorder set at 4 mm min−1 were used for the detection. The entire mixture was resolved as five peaks with retention times ranging from 2·75 to 9·65 minutes. This continuous, simple and rapid method of detection, extraction and identification may be useful for routine laboratory testing of residual antimicrobial agents in food.  相似文献   
185.
As representatives of herbicides which are used in rice fields in Japan, paraquat (Pa), chlormethoxynil (Ch), a mixture of thiobencarb and simetryne (BS), and oxadiazon (Ox) were chosen for investigation of their effects on invertebrates in soil and flood water of rice paddies. With regard to nematodes, plant-parasitic species from rice roots, mainly Hirschmaniella oryzae, were the most abundant in B plots. All herbicide plots yielded more plant-parasitic nematodes from the soil than did the hand-weeded control plots. Predaceous mononchids, which mostly live in the surface stratum (oxidation zone) were drastically decreased in B and Ch plots. The vertical distribution of the nematode population showed similar patterns between control plots and those to which Pa was applied 2 months before flooding, and also between Ch and B plots, both of which herbicides were applied after flooding. Measurement of the similarity values of the nematode community confirmed these results. Invertebrates in the flood water were not adversely affected in Pa plots, but other herbicides brought about a ripid decrease in arthropods. However, water fleas (excluding copepods) were restored to their usual population levels within a month. The similarity values of the insect community were high between the Ch and B plots (as found for nematodes). Pond snails increased in herbicide-treated plots, especially in Ox plots which had a dense growth of green algae.  相似文献   
186.
A total of 772 canine fecal specimens were collected in Tochigi in 1979, 1991 and 2001. The frequency of dogs that were kept indoor in 2002 (72.8%) was significantly higher than that for 1979 (21.2%, P < 0.001) and 1991 (40.6%, P < 0.01). The frequency of parasitized dogs in 2002 (18.8%) was significantly lower than that for 1979 (41.9%, P < 0.01). The findings of this study confirm the declining trend in Japan in the prevalence of helminth parasites in dogs, particularly Ancylostoma caninum and Trichuris vulpis. The reduction in the frequency of dogs with helminths may be mainly a result of the improvement in the environment and the routine use of filaricides.  相似文献   
187.
In dairy cows, retained fetal membranes (RFM) affect reproductive performance. The aim of this study was to examine the leukocyte counts and the gene expression of tumour necrosis factor α (TNFα), interleukin 1β (IL‐1β), IL‐8, and IL‐10 in polymorphonuclear leukocytes (PMNs) and peripheral blood mononuclear cells (PBMCs) in cows with (n = 5) or without (n = 5) RFM during the peripartum period. The lymphocyte counts in RFM cows were higher than those in control cows throughout the experiment (p < .05). The expression of IL‐8 in PMNs of control cows was higher (p < .05) compared with that of RFM cows postpartum. In cows with RFM, IL‐1β expression was higher (p < .05) in PMNs at 6 weeks postpartum whereas the expression of IL‐1β was lower (p < .05) in PBMCs at 4 weeks postpartum. The expression of IL‐10 in PBMCs of control cows was higher (p < .05) than that of RFM cows at 2 weeks prepartum and 4 weeks postpartum. Taken together, our data indicate that changes of gene expression of pro‐ and anti‐inflammatory cytokines in RFM cows might be associated with the delayed placental separation and development of uterine inflammation in RFM cows.  相似文献   
188.
189.
A 6-year-old female degu (Octodon degus) in good body condition was presented with a mass at the base of the tail. Following presentation and the owners’ approval, the tail of the degu was surgically amputated. The mass was submitted for pathological evaluation following the surgical procedure. Histologically, the mass was comprised of lobules and sheets of polygonal cells displaying moderate amounts of basophilic foamy cytoplasm (physaliferous cells). The pathological results of the tail mass were consistent with chordoma. Approximately 3 months following the tail amputation the patient died.  相似文献   
190.
Leaf photosynthesis, an important determinant of yield potential in rice, can be estimated from measurements of chlorophyll content. We searched for quantitative trait loci (QTLs) for Soil and Plant Analyzer Development (SPAD) value, an index of leaf chlorophyll content, and assessed their association with leaf photosynthesis. QTL analysis derived from a cross between japonica cultivar Sasanishiki and high-yielding indica cultivar Habataki detected a QTL for SPAD value on chromosome 4. This QTL explained 31% of the total phenotypic variance, and the Habataki allele increased the SPAD value. Chromosomal segment substitution line (CSSL) with the corresponding segment from Habataki had a higher leaf photosynthetic rate and SPAD value than Sasanishiki, suggesting an association between SPAD value and leaf photosynthesis. The CSSL also had a lower specific leaf area (SLA) than Sasanishiki, reflecting its thicker leaves. Substitution mapping under Sasanishiki genetic background demonstrated that QTLs for SPAD value and SLA were co-localized in the 1,798-kb interval. The results suggest that the phenotypes for SPAD value and SLA are controlled by a single locus or two tightly linked loci, and may play an important role in increasing leaf photosynthesis by increasing chlorophyll content or leaf thickness, or both.  相似文献   
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