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1.
Molina MF Qu HQ Rentfro AR Nair S Lu Y Hanis CL McCormick JB Fisher-Hoch SP 《Biochemical and biophysical research communications》2011,412(4):728-731
Objective
Previous studies in mice and humans observed down-regulation of the gene expression of ATP6V1H associated with type 2 diabetes. This study identified prospectively changes in ATP6V1H expression before and after overt diabetes.Methods
Expression of ATP6V1H in peripheral blood was compared pre and post development of diabetes in nine individuals.Results
Considerable variation of ATP6V1H mRNA levels was observed between different individuals. However, within each individual the decrease in expression of ATP6V1H with the development of diabetes was highly statistically significant.Conclusions
ATP6V1H may represent a critical molecular mechanism involved in the development of type 2 diabetes and its compilations through its important regulatory effect on vacuolar-ATPase activity. 相似文献2.
Matthew S. Kokotilo Jodi Carter Aducio Thiesen Ming H. Chen Angela Ochs Rachel G. Khadaroo Thomas A. Churchill 《Cryobiology》2010,61(3):236-242
Introduction
Our lab has developed an effective nutrient-rich solution that facilitates energy production and control of oxidative stress during static cold storage of the intestine; however, the requirement for oncotic agents, such as hydroxyethylstarch (HES), has not been evaluated. This study investigated the effectiveness and requirement for HES in an intraluminal preservation solution during a clinically relevant period of cold storage.Methods
Rat intestines were procured, including an intravascular flush with University of Wisconsin solution followed by a ‘back table’ intraluminal flush with a nutrient-rich preservation solution containing varying amounts of HES (n = 6 per group): Group 1, 0%; Group 2, 2.5%; Group 3, 5%; Group 4, 10%. Energetics, oxidative stress, and morphology were assessed over a 24 h time-course of cold storage.Results
Overall, the 5% HES solution, Group 3, demonstrated superior energetic status (ATP and total adenylates) compared to all groups, P < 0.05. Malondialdehyde levels indicated a reduction in oxidative stress in Groups 3 and 4 (P < 0.05). After 12 h, median modified Parks’ grades for Groups 2 and 3 were significantly lower than Groups 1 and 4, P < 0.05.Conclusion
Our data suggests that when employing an intraluminal preservation solution for static organ storage, oncotic support is a fundamental requirement; 5% HES is optimal. 相似文献3.
Erratum
The expression of a rab-related gene, rab 18, is induced by abscisic acid during the cold acclimation process of Arabidopsis thaliana (L.) Heynh 相似文献4.
Background
Pancreatic cancer is one of the most aggressive human tumors and the development of new therapeutic approaches is particularly urgent since current therapies are not effective. The use of pro‐drug‐activating genes is a possible approach for cancer gene therapy.Methods
The present study evaluated the efficiency of the cytochrome P4502B1 (CYP2B1) suicide gene that encodes the enzyme responsible for activating the pro‐drug cyclophosphamide (CPA), in pancreatic tumor cells invitro and in vivo. The effects on tumor growth of the combination of two suicide systems, CYP2B1/CPA and herpes simplex virus thymidine kinase gene/ganciclovir (HSVtk/GCV), were also studied.Results
Retroviral CYP2B1 transfer followed by CPA treatment highly sensitized pancreatic tumor cells NP‐9, NP‐18, and NP‐31, and led to stabilization of tumor growth in a pancreatic tumor model. Differences in tumor volume at the end of the treatment were statistically significant when compared with animals injected with CPA alone. The combination of both suicide systems CYP2B1/CPA and HSVtk/GCV in vitro resulted in a potentiation of the killing effect. However, no potentiation was achieved in vivo, although retardation in tumor growth was evident.Conclusions
The results show that in situ transduction of pancreatic tumor cells with the CYP2B1 gene by retroviral vectors clearly increases the sensitivity to CPA. Moreover, they suggest that in order to achieve a potentiation on cell killing when the two suicide systems HSVtk/GCV and CYP2B1/CPA are combined, co‐expression of both genes in the same tumor cell would be necessary. Copyright © 2002 John Wiley & Sons, Ltd.5.
Erratum
Cloning and characterization of a pathogen-induced chitinase in Brassica napus 相似文献6.
In a previous article (8) a geometrical study of the five-membered ring showed that: a) for the case of the 20 symmetrical C2 and Cs conformations, the pseudorotation formulae for the torsion angles are a geometrical property of the ring; b) geometrical considerations alone are unable to define the puckering amplitude, the bond angle values, and the pathway between two symmetrical conformations. Here we examine how the energy equations enable us to define the deformation amplitude
m, establish the bond angles expressions and check the energy invariability along the pseudorotation circuit. The problem is next developed fully in the case where the bond and torsional energy only are considered: the literal expression1 of
m is then given as a function of the bond angle which cancels out the bond angle energy. A numerical application is carried out on cyclopentane and the values of the parameters Kt, K1 and used in the Conformational energy calculations are considered.Notations used 1 i
bond lengths 1 in the case of the regular ring
-
i
torsional angles
-
i
bond angles
-
3/5 = 108
-
4/5 = 144
-
,
i
i – = complement to the 108 bond angle
i
-
T
-
E
Conformational energy of the 5-membered ring
-
E
Conformational energy difference between planar and deformed ring
-
A
n
Coefficients of the energy development in terms of
-
E
i
l
Bond energy relative to atom i (associated with angle
i)
-
K
i
l
Bond constant relative to atom i (associated with angle
i)
-
E
i
l
Torsional energy relative to the i
th bond (associated with angle
i)
-
k
i
l
Torsional constant relative to the i
th bond (associated with angle
i)
-
i
Angle
i value corresponding to zero bond energy E
i
l
(when the 5 atoms of the ring are identical,
i )
-
r
ij
Distance between atoms i and j
-
q
i
Charge carried by atom i
-
e
Constant of proportionality including the effective dielectric constant
-
A
ij, Bij, dij
Coefficients dependent on the nature of the atoms i and j and accounted for in the Van der Waals energy and hydrogen bond expressions
-
S (r
ij)
Electrostatic contribution to the hydrogen bond energy
-
P
Pseudorotation phase angle
-
m
Maximum torsional angle value characterising the deformation amplitudeM 相似文献
7.
Unbiased random mutagenesis contributes to a better understanding of the virulent behaviour of Paenibacillus larvae
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Aims
American foulbrood, caused by the Gram‐positive bacteria Paenibacillus larvae, is one of the most severe bacterial diseases of the European honey bee. The bacterium has been known for long, but only the last decade the mechanisms used by the pathogen to cause disease in its host are starting to unravel. In this study, the knowledge of this virulent behaviour is expanded and several possible virulence factors are suggested.Methods and Results
Identification of possible virulence factors has been done by random mutagenesis to ensure an unbiased approach. A library of mutants was tested for a significant difference in virulence using in vitro exposure assays. Affected loci were characterized and their potential to contribute in virulence of the pathogen was assessed.Conclusions
The identified mutated loci dacB, dnaK, metN, ywqD, lysC, serC and gbpA are known to encode for virulence factors in other bacteria and are suggested to play a similar role in P. larvae.Significance and Impact of the Study
The study identified new possible virulence factors for P. larvae genotype ERIC I in an unbiased way. This contributes to the knowledge and understanding of the possible mechanisms used by this pathogen to colonize and kill its host. 相似文献8.
Aims
The aim of our research was to select, identify and characterize an isolate of lactic acid bacteria to be considered as a vaginal probiotic.Methods and Results
Thirty‐five isolates of Pediococcus spp. showed bacteriocinogenic activity against Listeria monocytogenes and the ability to survive in simulated vaginal fluid (SVF) at pH 4·2. One isolate of Pediococcus spp. was selected and characterized to evaluate its safety before the use as vaginal probiotic. Pediococcus pentosaceus SB83 did not show the presence of virulence factors such as the production of gelatinase, lipase and DNase, haemolytic activity, nor the presence of virulence genes (genes esp, agg, gelE, efaAfm, efaAfs, cylA, cylB and cylM). Pediococcus pentosaceus SB83 was considered sensitive to chloramphenicol, gentamicin, streptomycin, kanamycin, erythromycin and ampicillin. This strain was considered resistant to tetracycline and vancomycin. Pediococcus pentosaceus SB83 was a biofilm producer at different pH values (4·2, 5·5 and 6·5) in SVF and in de Man, Rogosa and Sharpe medium.Conclusions
The in vitro results provide a basis for the use of P. pentosaceus SB83 as a vaginal probiotic, to prevent colonization by L. monocytogenes in pregnant women.Significance and Impact of Study
The application of vaginal probiotics could have the potential for preventing vaginal infections and consequently reduce abortion and neonatal infections. 相似文献9.
Erratum
Cytosine deaminase as a negative selective marker for Arabidopsis 相似文献10.
11.
J.S. Stern J. Peerson A.T. Mishra M.V. Sadasiva Rao K.P. Rajeswari 《Obesity (Silver Spring, Md.)》2013,21(5):921-927
Objective:
To evaluate the efficacy of an herbal blend.Design and Methods:
A randomized, double‐blind, clinical trial in 60 subjects with body mass index (BMI) between 30 and 40 kg/m2. Participants were randomized into two groups receiving either 400 mg herbal capsules or 400 mg placebo capsules twice daily. The herbal blend comprises of extracts from Sphaeranthus indicus and Garcinia mangostana. Participants received a standard diet (2,000 kcal per day) and walked 30 min 5 days per week.Results:
After 8 weeks, significant net reductions in body weight (3.74 kg; P < 0.0001), BMI (1.61 kg/m2; P < 0.0001), and waist circumference (5.44 cm; P < 0.05) were observed in the herbal group compared with placebo. Additionally, a significant increase in serum adiponectin concentration was found in the herbal group versus placebo (P = 0.001). Adverse events were mild and were equally distributed between the two groups. In vitro studies in the 3T3‐L1 adipocyte cell line showed that the herbal extract markedly downregulated the expression of peroxisome proliferator‐activated receptor gamma, adipocyte‐differentiation related protein, and cluster of differentiation 36 but increased adiponectin expression. The herbal extract also reduced the expression and the recruitment of perilipin onto the membrane of lipid droplets.Conclusion:
Supplementation with the herbal blend resulted in a greater degree of weight loss than placebo over 8 weeks. 相似文献12.
Diana M. Higgins Lindsey Dorflinger Kristin L. MacGregor Alicia A. Heapy Joseph L. Goulet Christopher Ruser 《Obesity (Silver Spring, Md.)》2013,21(5):900-903
Objective:
Despite the high prevalence of overweight and obesity in the US military veterans, binge eating has not been examined in this population.Design and Methods:
Using a secondary data analysis approach, the prevalence and correlates of self‐reported binge eating among 45,477 overweight or obese veterans receiving care in Veterans Health Administration facilities were examined. Participants completed a 23‐item survey that assessed demographics, weight history, physical and mental health comorbidities, and eating habits during routine medical clinic visits. χ2 and logistic regression were used to examine the relationships among binge eating and demographic variables and medical and psychiatric comorbidities.Results:
Nearly, three‐quarters of the sample reported clinically meaningful binge eating (i.e., two or more times per week). Binge‐eaters were more likely to report higher body mass index, depression, anxiety, and type 2 diabetes (P <0.0001). After controlling for potentially confounding variables, male veterans were significantly more likely to report clinically meaningful binge eating than female veterans (P < 0.001).Conclusion:
These results have important implications for modifying weight management programs and highlight the need for the assessment and treatment to address binge eating, particularly among men and patients with type 2 diabetes. 相似文献13.
Background
The fliC and fljB genes in Salmonella code for the phase 1 (H1) and phase 2 (H2) flagellin respectively, the rfb cluster encodes the majority of enzymes for polysaccharide (O) antigen biosynthesis, together they determine the antigenic profile by which Salmonella are identified. Sequencing and characterisation of fliC was performed in the development of a molecular serotyping technique. 相似文献14.
A. Nur K. Hirota H. Yumoto K. Hirao D. Liu K. Takahashi K. Murakami T. Matsuo R. Shu Y. Miyake 《Journal of applied microbiology》2013,115(1):260-270
Aims
The aim of this study was to clarify the effects of homologous and heterologous extracellular DNAs (eDNAs) and histone‐like DNA‐binding protein (HLP) on Streptococcus intermedius biofilm development and rigidity.Methods and Results
Formed biofilm mass was measured with 0·1% crystal violet staining method and observed with a scanning electron microscope. The localizations of eDNA and extracellular HLP (eHLP) in formed biofilm were detected by staining with 7‐hydoxyl‐9H‐(1,3‐dichloro‐9,9‐dimethylacridin‐2‐one) and anti‐HLP antibody without fixation, respectively. DNase I treatment (200 U ml?1) markedly decreased biofilm formation and cell density in biofilms. Colocalization of eHLP and eDNA in biofilm was confirmed. The addition of eDNA (up to 1 μg ml?1) purified from Strep. intermedius, other Gram‐positive bacteria, Gram‐negative bacteria, or human KB cells into the Strep. intermedius culture increased the biofilm mass of all tested strains of Strep. intermedius, wild‐type, HLP‐downregulated strain and control strains. In contrast, the addition of eDNA (>1 μg ml?1) decreased the biofilm mass of all Strep. intermedius strains.Conclusions
These findings demonstrated that eDNA and eHLP play crucial roles in biofilm development and its rigidity.Significance and Impact of the Study
eDNA‐ and HLP‐targeting strategies may be applicable to novel treatments for bacterial biofilm‐related infectious diseases. 相似文献15.
Erratum
Expression of a chimeric CaMV 35S Bacillus thuringiensis insecticidal protein gene in transgenic tobacco 相似文献16.
P. R. Patnaik 《Bioprocess and biosystems engineering》1996,15(4):215-219
The sensitivities with respect to the initial state of five key variables describing the performance of a batch bioreactor have been computed from an experimentally validated kinetic model. The system has a recombinant Escherichia coli strain containing the plasmid pBR Eco gap, which codes for glyceraldehyde-3-phosphate dehydrogenase (GAPDH) in a complex medium. Since previous studies have shown the start-up sensitivities to be particularly important, the initial 10% of the duration of fermentation was chosen as the time span. The sensitivities of the cell mass, GAPDH and acetate increased with time while those of glucose and yeast extract remained practically constant.Acetate has a crucial role as it functions as both a product and a reactant. With no acetate in the inoculum, the sensitivities of acetate increased an order of magnitude faster than other sensitivities. However, upon addition of acetate through the inoculum, its sensitivities decreased the fastest and stabilised beyond a starting concentration of about 1 g/l whereas other sensitivities stabilised after 5 to 6 g/l of initial acetate. A three-dimensional envelope in the space of acetate concentration-time-relative sensitivity shows a locus of concentrations for minimum time-dependent acetate sensitivity; this may be maintained through fed-batch operation.List of Symbols
a
A/A0
-
A g/l
initial concentration at any time
-
A
0 g/l
initial acetate concentration
-
e
E/E0
-
E g/l
yeast extract concentration at any time
-
E
0 g/l
initial yeast extract concentration
-
g
G/G0
-
G g/l
glucose concentration at any time
-
G
0 g/l
initial glucose concentration
-
k
A
A
g/l
inhibition constant for acetate-dependent growth during the acetate phase
-
k
A
G
g/l
inhibition constant for acetate-dependent growth during the glucose phase
-
k
M
A
1/h
rate constant for acetate phase
-
k
M
G
1/h
rate constant for glucose phase
-
K
A
g/1
affinity constant for acetate
-
K
G
g/1
affinity constant for glucose
-
m
A
1/h
coefficient of maintenance in acetate
-
m
m
A
1/h
maximum value of m
A
-
m
G
1/h
coefficient of maintenance in glucose
-
m
m
G
1/h
maximum value of m
G
-
n
empirical constant
-
P
P/P0
-
P U/ml
GAPDH concentration at any time
-
P
0 U/ml
initial GAPDH concentration
-
s
c
(i,j)
sensitivity of y
i
to y
j(0) for A
0=c
-
t h
time
-
x
X/X0
-
X g/l
cell mass concentration at any time
-
X
0 g/l
initial cell mass concentration
-
y
1
x
- y2
g
- y3
a
- y4
e
-
y
5
p
-
y
x/A
A
g/g
yield coefficient for cell mass per unit mass of acetate during acetate phase
-
y
x/A
G
g/g
yield coefficient for cell mass per unit mass of acetate during glucose phase
-
y
x/G
g/g
yield coefficient for cell mass per unit mass of glucose
-
y
E/x
A
g/g
yield coefficient for yeast extract per unit cell mass during acetate phase
-
y
P/x
A
g/g
yield coefficient for yeast extract per unit cell mass during glucose phase
-
y
P/x
A
U/g
yield coefficient for GAPDH per unit cell mass during acetate phase
-
y
P/x
G
U/g
yield coefficient for GAPDH per unit cell mass during glucose phase
Greek Letters
0
proportionality constant for plasmid loss probability
-
1 1/h
maximum rate of plasmid replication
-
2 1/h
saturation constant of the host component of plasmid replication
-
regulation function (0 or 1)
-
regulation function (0 or 1)
-
exponent of growth inhibition term for acetate during the acetate phase
-
exponent of growth inhibition term for acetate during the glucose phase
-
A
1/h
specific growth rate during acetate phase
-
m
A
1/h
maximum value of A
- G 1/h
specific growth rate during glucose phase
-
m
G
1/h
maximum value of G
- c (i,j)
ratio of sensitivities, s
c
(i,j)/s
0(i,j)
-
nondimensional time, t
m
G
相似文献
17.
Hiroyuki Kawami Kazuhiro Yoshida Yoshiyuki Yamaguchi Toshiaki Saeki Tetsuya Toge 《Biotherapy》1993,6(1):33-39
To ascertain whether the tumor cells can regulate the host immune systems through the production of the cytokines or their receptors, we examined the expressions of tumor necrosis factor (TNF), tumor necrosis factor (TNF), interleukin 2 (IL-2) and interleukin 2 receptor alpha chain (IL-2R) on the human cancer cell lines by Northern blot analysis. We used K562 (leukemia cell line), MCF-7 (breast cancer cell line), LS180, HT29 (colon cancer cell lines), SH101 (gastric cancer cell line) and PH101 (pancreas cancer cell line). Expressions of TNF, TNF and IL-2 mRNA were not detected in any of the tumor cell lines. However, 1.4 and 3.5 kilobases of the IL-2R mRNA were expressed in the PH101 cells, but not in the other five cell lines. Furthermore, IL-2R was detected on the cell surface of the PH101 cells by the flow-cytometric analysis with an anti-IL-2R monoclonal antibody. Interestingly, the soluble IL-2R (sIL-2R) was found in the conditioned media obtained from the PH101 cell culture with a sandwich enzyme immunoassay. Moreover, the sIL-2R secreted from the PH101 cells blocked the IL-2 dependent lymphocyte proliferation. These results indicate that the expression of IL-2R on PH101 might suppress the IL-2 induced lymphocyte proliferation. 相似文献
18.
Hirano M Nakamura S Mitsunaga F Okada M Shimuzu K Imamura T 《The journal of gene medicine》2002,4(5):560-566
Background
Materno‐fetal transfer of intravenously administered liposome‐plasmid DNA complexes has been demonstrated only in mice. Studies on its materno‐fetal transfer in the pregnant monkey model is needed because of critical differences in placental structure between primates including humans and rodents.Methods
The reporter plasmid pEGFP‐C1 was formulated in cationic lipid containing polybrene and vesicular stomatitis virus G protein. The fusogenic liposome‐plasmid DNA complexes were intradermally injected into pregnant common marmosets (N=2), a New World monkey, near term. DNA extracted from fetal tissues was subjected to PCR for detection of the egfp gene. Confocal microscopy and immunostaining were performed to determine the sites of transgene expression in the fetal organs.Results
The egfp gene was detected in fetal blood and major organs (heart, liver, lung). The encoded protein was mainly produced in the endothelial cells of blood vessels in the fetal lungs.Conclusions
This is the first report on materno‐fetal transfer of intradermally administered fusogenic liposome‐plasmid DNA complexes and fetal expression of a transgene in primates. Copyright © 2002 John Wiley & Sons, Ltd.19.
Peter JI Ellis Lydia Ferguson Emily J Clemente Nabeel A Affara 《BMC evolutionary biology》2007,7(1):171
Background
The male-specific region of the mouse Y chromosome long arm (MSYq) contains three known highly multi-copy X-Y homologous gene families, Ssty1/2, Sly and Asty. Deletions on MSYq lead to teratozoospermia and subfertility or infertility, with a sex ratio skew in the offspring of subfertile MSYqdel males 相似文献20.
Past vegetation dynamics in the Yellowstone region highlight the vulnerability of mountain systems to climate change
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Virginia Iglesias Cathy Whitlock Teresa R. Krause Richard G. Baker 《Journal of Biogeography》2018,45(8):1768-1780