Currently, there are few reports on the isolation of microorganisms from goat milk and goat cheese that have antibacterial activity. In particular, there are no reports on the isolation of ...microorganisms with antibacterial activity from these products in central Mexico. Our objective was to isolate bacteria, from goat products, that synthesized antimicrobial peptides with activity against a variety of clinically significant bacteria. We isolated and identified
Lactobacillus rhamnosus
,
L. plantarum
,
L. pentosus
,
L. helveticus
and
Enterococcus faecium
from goat cheese, and
Aquabacterium fontiphilum
,
Methylibium petroleiphilum
,
Piscinobacter aquaticus
and
Staphylococcus xylosus
from goat milk. These bacteria isolated from goat cheese were able to inhibit
Staphylococcus aureus
,
Bacillus cereus
,
Escherichia coli
,
Listeria monocytogenes
,
L. inoccua
,
Pseudomona aeruginosa
,
Shigella flexneri
,
Serratia marcescens
,
Enterobacter cloacae
and
Klebsiella pneumoniae.
In addition, bacteria from goat milk showed inhibitory activity against
B. cereus
,
L. lactis
,
E. coli
,
S. flexneri
,
E. cloacae
and
K. pneumonia
;
S. aureus
,
L. innocua
,
S. agalactiae
and
S. marcescens.
The bacteriocins produced by these isolates were shown to be acid stable (pH 2–6) and thermotolerant (up to 100 °C), but were susceptible to proteinases. When screened by PCR for the presence of nisin, pediocin and enterocin A genes, none was found in isolates recovered from goat milk, and only the enterocin A gene was found in isolates from goat cheese.
Originally described in cattle, conglutinin belongs to the collectin family and is involved in innate immune defense. It is thought that conglutinin provides the first line of defense by maintaining ...a symbiotic relationship with the microbes in the rumen while inhibiting inflammatory reactions caused by antibodies leaking into the bloodstream. Due to the lack of information on the similar lectins and sequence detection in goats, we characterized the goat conglutinin gene using RACE and evaluated the differences in its gene expression profile, as well as in the gene expression profiles for surfactant protein A, galectins 14 and 11, interleukin 4 and interferon-gamma in goats. We used Saanen and Anglo Nubian F2 crossbred goats monitored over a period of four months and characterized them as resistant (R) or susceptible (S) based on the average values of EPG counts. Goat conglutinin was similar to bovine conglutinin, but its gene expression varied among different tissues. However, as with bovine conglutinin, it was most highly expressed in the liver. Variation in conglutinin (R=24.3±3.9; S=23.5±2.6, p=0.059), protein surfactant A (R=23.8±5.2, S=24.4±2.3, p=0.16), galectin 14 (R=15.9±3.5, S=14.7±6.2, p=0.49) and galectin l1 gene expression (R=25.4±2.6, S=25.8±3.7, p=0.53) was not significant between groups. However, there were weak correlations between interleukin 4 and the protein surfactant A gene (r=0.459, p=0.02) and between interleukin 4 and galectin 11 (r=0.498, p=0.01). Strong correlation between interferon-gamma and galectin 14 (r=0.744, p=0.00) was observed. Galectin 14 was negatively correlated with the number of nematodes in the goat (r=-0.416, p=0.04) as well as the EPG count (r=-0.408, p=0.04). This is the first study to date that identifies the gene expression of conglutinin, surfactant protein A and galectins 14 and 11 in the goat abomasum. In conclusion, we present evidence that lectin is involved in the immune response to gastrointestinal nematodes, which suggests that collectins and galectins are involved in the molecular recognition of helminths.
Streptomyces
spp. are Gram-positive bacteria well-known for their ability to produce antibiotics and other metabolites, but few studies on bacteriocins produced by these bacteria have been reported. ...We tested eight
Streptomyces
strains against different pathogenic bacteria, and selected
S. griseus
,
S. nigrescens
,
S. bottroprensis
, and
S. violaceoruber
for further study based on their inhibitory effects against bacteria, including human pathogens.
S. bottropensis
reached its highest activity at 312 h and was higher than the activities of
S. violaceoruber
and
S. nigrescens
. The best condition for bacteriocin precipitation was using diammonium sulfate at 50% saturation. Bacteriocins were susceptible to proteinase treatments and stable at high temperature (up to 100 °C). The highest inhibitory activities were observed between pH 5 and 6. Cross-activity assays indicated that each
Streptomyces
strain produced different bacteriocins. When preparations of
S. griseus
and
S. nigrescens
were subjected to SDS-PAGE, bands of inhibition were observed in the gel overlay assay at a position corresponding to ~ 2 and 3 kDa, respectively, suggesting that both strains are potential sources for novel bacteriocins.
Pyrite bio-oxidation by chemolithotrophic acidophile bacteria has been applied in the mining industry to bioleach metals or to remove pyritic sulfur from coal. In this process, it is desirable to use ...autochthonous and already adapted bacteria isolated directly from the mining sites where biomining will be applied. Bacteria present in the remnant solution from a mining company were identified through cloning techniques. For that purpose, we extracted total RNA and performed reverse transcription using a novel pair of primers designed from a small region of the 16S gene (V1–V3) that contains the greatest intraspecies diversity. After cloning, a high proportion of individuals of the strains ATCC-23270 (NR_074193.1 and NR_041888.1) and DQ321746.1 of the well-known species Acidithiobacillus ferrooxidans were found, as well as two new wild strains of A. ferrooxidans. This result showed that the acidic remnant solution comprises a metapopulation. We assayed these strains to produce bioferric flocculant to enhance the subsequent pyrite bio-oxidation, applying two-stage chemical–bacterial oxidation. It was shown that the strains were already adapted to a high concentration of endogenous Fe2+ (up to 20 g·L−1), increasing the volumetric productivity of the bioferric flocculant. Thus, no preadaptation of the community was required. We detected Au and Ag particles originally occluded in the old pyritic flotation tailings assayed, but the extraction of Au and Ag by cyanidation resulted in ca. 30.5% Au and 57.9% Ag.
Validation and Calibration of ASCAT Using CMOD5.n Verspeek, J.; Stoffelen, A.; Portabella, M. ...
IEEE transactions on geoscience and remote sensing,
2010-Jan., 2010, 2010-01-00, 20100101, Letnik:
48, Številka:
1
Journal Article
Recenzirano
Odprti dostop
The Advanced Scatterometer (ASCAT) onboard the Metop-A satellite became operational shortly after launch in 2006, and an absolute calibration using three transponders was achieved in November 2008. ...In this paper, we describe how the CMOD5.n ocean backscatter geophysical model function (GMF), which was derived using data from previous scatterometers onboard the European Remote Sensing 1 and 2 satellites (ERS-1 and ERS-2), was used to derive backscatter bias correction factors. The purpose is to remove the bias between ASCAT backscatter data and the CMOD5.n GMF output which allows these data to be used in place of ERS data in existing wind processing algorithms. The ASCAT Wind Data Processor, developed at the Royal Netherlands Meteorological Institute (KNMI), applies the bias correction factors to ASCAT data and uses CMOD5.n to retrieve wind vectors in order to produce an operational wind product. This resulted in a stable and high-quality ASCAT wind product since February 2007. We validate this product by comparing it to the European Centre for Medium-range Weather Forecasts (ECMWF) winds and buoy measurements. The bias correction factors indicate that ASCAT data and the GMF differ by roughly 0.3 dB below 55 ? and up to 0.8 dB above 55 ? . A possible explanation lies in CMOD5.n which has been poorly validated in this incidence angle regime. Validation of ASCAT data using the ocean calibration method confirms this result and also indicates that bias-corrected data are everywhere within 0.3 dB of CMOD5.n. The wind product validation shows an rms error of 1.3 m ?s -1 in wind speed and 16 ? in wind direction when compared to ECMWF winds. This is better than the results achieved using ERS scatterometer data. Against buoy winds, we find an rms error wind component error of approximately 1.8 m ?s -1 . These results show that the ASCAT wind product is of high quality and satisfies its wind component accuracy requirement of 2 m ?s -1 .
Nitric oxide production in the vascular endothelium is promoted by diverse agonists that transiently increase intracellular
Ca 2+ concentration and activate the endothelial nitric-oxide synthase ...(eNOS), a Ca 2+ /calmodulin-dependent enzyme. eNOS is acylated by the fatty acids myristate and palmitate and is targeted thereby to plasmalemmal
signal-transducing domains termed caveolae. eNOS enzyme activity is markedly attenuated by its interactions with caveolin,
the structural scaffolding protein of caveolae. We have discovered that in living cells, the eNOS-caveolin heteromeric complex
undergoes cycles of dissociation and re-association modulated by Ca 2+ -mobilizing agonists. Calcium ionophore A23187 and the muscarinic cholinergic agonist carbachol both promote the dissociation
of eNOS from caveolin in cultured cells, associated with translocation of eNOS from caveolae. As Ca 2+ i returns to basal levels, eNOS re-associates with caveolin, and the inhibited enzyme complex is then restored to caveolae,
a process accelerated by palmitoylation of the enzyme. These data establish an eNOS-caveolin regulatory cycle, wherein enzyme
activation is modulated by reversible protein-protein interactions controlled by Ca 2+ /calmodulin and by enzyme palmitoylation. Alterations in this cycle are likely to have an important influence on nitric oxide-dependent
signaling in the vascular wall.
The new neutron time-of-flight facility (n_TOF) has been built at CERN and is now operational. The facility is intended for the measurement of neutron induced cross-sections of relevance to ...Accelerator Driven Systems (ADS) and to fundamental physics. Neutrons are produced by spallation of the
20
GeV/c
proton beam, delivered by the Proton Synchrotron (PS), on a massive target of pure lead. A measuring station is placed at
≈185
m
from the neutron producing target, allowing high-resolution measurements. The facility was successfully commissioned with two campaigns of measurements, in November 2000 and April 2001. The main interest was concentrated in the physical parameters of the installation (neutron fluence and resolution function), along with the target behavior and various safety-related aspects. These measurements confirmed the expectations from Monte Carlo simulations of the facility, thus allowing to initiate the foreseen physics program.
T cell recognition of common and type-specific herpes simplex virus (HSV) glycoproteins was measured in 72 subjects. T cells were stimulated with whole HSV-2 antigen and glycoproteins gB2, gD2, and ...gG2. T cell proliferation in response to HSV-2 antigen and gG2 was significantly higher in subjects with HSV-2 infection than in those with HSV-l infection only; responses to gB2 and gD2 were the same. T helper (Th) type 1 and Th2 cytokine production in response to whole HSV-2 antigen, gB2, and gD2 was evaluated in 33 subjects. Interleukin (IL)-2 and interferon-γ responses to most antigens were significantly higher among HSV-2–seropositive subjects than among seronegative subjects. IL-4 synthesis was negligible; IL-10 was produced in seronegative and seropositive persons, but HSV-2 antigen responses were significantly higher in HSV-2–seropositive persons. Naturally acquired immunity to HSV involves T cell recognition of common and type-specific glycoproteins, prominent Thl responses, and discordant Th2 responses with little IL-4 but substantial IL-10 production.
Between January 1983 and September 1992, 32 myocutaneous flaps were fashioned in 28 patients for reconstruction following treatment of genitourinary malignancies or complex pelvic fistulas. Of the ...myocutaneous flaps 14 were used to obtain primary soft tissue coverage of large but otherwise uncomplicated wounds and 10 were used to cover previously irradiated resection sites. Four myocutaneous flaps were used to repair complex radiation-induced fistulas involving the bladder, vagina, urethra and rectum. Flaps were used to cover infected or nonhealing open wounds in 8 cases, 4 of which also had been previously irradiated. Myocutaneous flap donor sites were the tensor fascia lata in 11 cases, gracilis in 9, rectus abdominis in 10 and rectus femoris in 2. There was 1 major complication (flap loss) and 9 minor complications. There were no perioperative deaths. Myocutaneous flaps are an effective means of covering large groin, perineal and lower abdominal surgical defects after radical surgery.
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