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Publication
Journal: Journal of Pediatrics
October/24/1981
Abstract
We have evaluated a commercially available latex agglutination system for the detection of C-reactive protein in CSF by a prospective study of 56 patients with CSF pleocytosis. On initial lumbar puncture, C-RP was detected in 100% (24/24) of patients with culture-proven bacterial meningitis, compared to 6% (2/32) of patients in the nonbacterial group (chi 2 c = 44.8, P less than 0.0001). C-RP in CSF had a sensitivity of 1.0 and a specificity of 0.94 for detecting culture-positive, bacterial meningitis. It was a more sensitive test for differentiating bacterial from nonbacterial meningitis on initial CSF examination than was the number of CSF leukocytes, the absolute number of CSF polymorphonuclear leukocytes, CSF glucose concentration, CSF protein concentration, or Gram staining of CSF. Detection of C-RP by latex agglutination may prove to be a practical and reliable method for differentiating bacterial from nonbacterial meningitis.
Publication
Journal: Neuroscience
May/31/2011
Abstract
During the consolidation of fear memory, it has been shown that GABA(A) receptors (GABA(A)R) are rapidly downregulated in amygdala. This rapid decrease in GABA(A)R functioning may permit transient hyperexcitablity, contributing to cellular mechanisms of memory consolidation. Memory consolidation also requires brain-derived neurotrophic factor (BDNF) activation of tyrosine receptor kinase B (TrkB) receptors in the amygdala and hippocampus. We hypothesized that rapid internalization of GABA(A)Rα1 is mediated via TrkB activation of PKA and PKC-dependent processes. Primary neuronal cell cultures, from postnatal day 14-21 mouse amygdala and hippocampus, were analyzed with immunofluorescence using cell-surface, whole-cell permeabilization, and antibody internalization techniques, as well as with (3)H-muscimol binding assays. In both hippocampal and amygdala cultures, we found a >60% reduction in surface GABA(A)Rα1 within 5 min of BDNF treatment. Notably, the rapid decrease in surface GABA(A)Rα1 was confirmed biochemically using surface biotinylation assays followed by western blotting. This rapid effect was accompanied by TrkB phosphorylation and increased internal GABA(A)Rα1 immunofluorescence, and was blocked by k252a, a broad-spectrum tyrosine kinase antagonist. To further demonstrate TrkB specificity, we used previously characterized TrkB(F616A) mice, in which the highly selective TrkB-mutant specific antagonist, 1NMPP1, prevented the BDNF-dependent GABA(A)Rα1 internalization. In hippocampus, we found both PKA and PKC inhibition, using Rp-8-Br-cAMP and Calphostin C, respectively, blocked GABA(A)Rα1 internalization, whereas inhibition of MAPK (U0126) and PI3K (LY294002) did not prevent rapid internalization. By contrast in amygdala cultures, Rp-8-Br-cAMP had no effect. Together, these data suggest that rapid GABA(A)R internalization during memory consolidation is BDNF-TrkB dependent. Further, it appears that hippocampal GABA(A)R internalization is PKA and PKC dependent, while it may be primarily PKC dependent in amygdala, implying differential roles for TrkB-dependent kinase activation in BDNF-dependent memory formation.
Publication
Journal: Journal of Nutrition
December/29/2010
Abstract
Rye whole grain and bran intake has shown beneficial effects on prostate cancer progression in animal models, including lower tumor take rates, smaller tumor volumes, and reduced prostate specific antigen (PSA) concentrations. A human pilot study showed increased apoptosis after consumption of rye bran bread. In this study, we investigated the effect of high intake of rye whole grain and bran on prostate cancer progression as assessed by PSA concentration in men diagnosed with prostate cancer. Seventeen participants were provided with 485 g rye whole grain and bran products (RP) or refined wheat products with added cellulose (WP), corresponding to ~50% of daily energy intake, in a randomized controlled, crossover design. Blood samples were taken from fasting men before and after 2, 4, and 6 wk of treatment and 24-h urine samples were collected before the first intervention period and after treatment. Plasma total PSA concentrations were lower after treatment with RP compared with WP, with a mean treatment effect of -14% (P = 0.04). Additionally, fasting plasma insulin and 24-h urinary C-peptide excretion were lower after treatment with RP compared with WP (P < 0.01 and P = 0.01, respectively). Daily excretion of 5 lignans was higher after the RP treatment than after the WP treatment (P < 0.001). We conclude that whole grain and bran from rye resulted in significantly lower plasma PSA compared with a cellulose-supplemented refined wheat diet in patients with prostate cancer. The effect may be related to inhibition of prostate cancer progression caused by decreased exposure to insulin, as indicated by plasma insulin and urinary C-peptide excretion.
Publication
Journal: Journal of Chromatography A
March/6/2005
Abstract
Analytical characterization of monoclonal antibodies has been hindered by the lack of appropriate chromatographic methods to be used in conjunction with high-resolution MS. Current methodologies for standard RP-HPLC are incompatible with antibodies due to irreproducibility, low recovery, short column lifetimes, and poor resolution of degradation products. An analytical RP-HPLC-MS method was developed for monitoring and characterizing intact IgG1antibodies. Key parameters required for improved chromatographic resolution included long alkyl chains of the stationary phase (Zorbax SB300 CC and combination of trifluoroacetic acid and heptafluorobutyric acid ion-pairing agents. RP chromatographic separation of degradation species and C-terminal lysine variants along with the characterization of glycosylation profile by mass spectrometry demonstrates the capability of this method for whole antibody analysis.
Publication
Journal: Vaccine
April/23/2009
Abstract
The haemagglutinin (HA) content is an important specification of influenza vaccines. Recently, a reversed-phase high performance liquid chromatography (RP-HPLC) method for quantification of HA in PER.CC, Drissi Saidi M, Dijkstra R, Kars C, Tjon CMS-K, Weverling GJ et al. Haemagglutinin quantification and identification of influenza A&B strains propagated in PER.CRP-HPLC method. Vaccine 2006;24:3137-44]. This RP-HPLC assay is based on measuring the peak area of HA1, the hydrophilic subunit of HA, which turned out to be proportional to the amount of HA analyzed. Here, we present data demonstrating that this RP-HPLC method is also highly suitable for HA quantification of active and BPL- or formaldehyde-inactivated egg-based and MDCK cell-based whole virus samples, including egg allantoic harvest, and in final (monovalent) subunit vaccines, including those for pandemic H5N1 strains and for virosomal vaccines. In addition, the RP-HPLC assay was demonstrated to be a very powerful tool in the early stages of seasonal influenza vaccine production, when homologous serial radial immunodiffusion (SRID) reagents are not yet available, enabling fast and reliable viral growth studies in eggs in order to select the best growing virus strains or reassortants for the production of the seasonal trivalent influenza vaccine. Because of its high sensitivity, the RP-HPLC assay has shown its enormous value in supporting small scale MDCK-based (H5N1) influenza virus production models. Finally, the observed differences between HA1 molecules from various HA subtypes in UV absorbance, FLD response, and in the actual retention times in RP-HPLC are discussed in relation to the primary structure of the HA1 molecules studied.
Publication
Journal: European journal of biochemistry
October/28/1982
Abstract
When grown aerobically in the dark, Rhodopseudomonas sphaeroides develops a respiratory chain similar to that in mitochondria and the photosynthetic apparatus is suppressed. The aa3-type cytochrome c oxidase from Rps. sphaeroides has been purified in Triton X-100 by affinity chromatography with Sepharose 4B coupled to yeast cytochrome c. The oxidase contains 14 nmol heme a/mg protein and is composed of three polypeptide subunits with relative molecular masses of 45000, 37000 and 35000. The enzyme is highly active in the presence of detergents, with a maximal velocity of 300 s-1/mol oxidase using either yeast or horse-heart cytochrome c. The Rps. sphaeroides oxidase is cross-reactive with antibodies directed against the oxidases from Paracoccus denitrificans and Saccharomyces cerevisiae. A particularly close relationship is indicated in the case of P. denitrificans. The Rps. sphaeroides oxidase has been incorporated into phospholipid vesicles. The resulting oxidase in these vesicles demonstrates high enzymatic activity and a respiratory control ratio of 5. Using these vesicles, no evidence for proton extrusion accompanying cytochrome c oxidation was observed. The data suggest that the Rps. sphaeroides oxidase does not function as a proton pump.
Publication
Journal: Metabolism: Clinical and Experimental
April/24/2003
Abstract
Previous in vivo studies in cardiomyopathic hamsters suggested that the expression of vasopressin (AVP) V2 mRNA is up- regulated by angiotensin II. The present study was performed to determine whether angiotensin II plays a role in regulating the expression of AVP V2 mRNA and aquaporin-2 (AQP2) mRNA in the inner medullary collecting duct (IMCD) of the male Wistar rat. The expression of AVP V2 mRNA and AQP2 mRNA in the IMCD was measured by competitive reverse-transcriptase polymerase chain reaction (RT-PCR). Six groups of experiments were performed. In the first group, we incubated IMCD with 3 different doses of angiotensin II (10(-11), 10(-9) and 10(-7) mol/L). Angiotensin II caused a significant increase in the AVP V2 mRNA in a dose-dependent manner but its effect on AQP2 mRNA was modest. This effect of angiotensin II was inhibited by angiotensin II receptor antagonist, [Sar1,Ile8]-angiotensin II. To examine the role of PKA in mediating an increase in AVP V2 mRNA expression, we incubated IMCD with 10(-7) and 10(-11) M of angiotensin II in the presence of a specific protein kinase A (PKA) inhibitor, Rp diasteroisomer of adenosine 3'-5'-cylic monophosphothionate (Rp-cAMPS). The angiotensin II-induced upregulation of V2 mRNA was abolished. In the fourth group, we examined the effect of protein kinase C (PKC) inhibition on V2 mRNA expression. The upregulation of V2 mRNA induced by angiotensin II was greatly exaggerated when IMCD was incubated with angiotensin II and RO-31-8220 (PKC inhibitor). In the fifth and sixth groups of studies, we determined the direct effect of PKA and PKC on regulating the expression of V2 mRNA and AQP2 mRNA in the IMCD, respectively. Dibutryl cAMP stimulated an upregulation in the expression of V2 mRNA and AQP2 mRNA, whereas phorbol esters suppressed the expression of V2 mRNA. These results suggested that PKA stimulates and PKC suppresses the expression of V2 mRNA in the IMCD of the kidney.
Publication
Journal: Analytical Biochemistry
August/12/2004
Abstract
An improved microscale synthesis of 2-tritiated isopropanol ([2-3H]iPrOH) and R-tritiated reduced beta-nicotinamide adenine dinucleotide 2(')-phosphate (R-[4-3H]NADPH) is presented. The current procedure offers high yield, high purity, and small-quantity synthesis and is shorter than previous procedures. [2-3H]iPrOH was prepared by reduction of acetone with [3H]NaBH(4) under reflux conditions. [2-3H]iPrOH was used to reduce NADP(+) to R-[4-3H]NADPH with alcohol dehydrogenase from Thermoanaerobium brockii at 40 degrees C. This equilibrium reaction was drawn toward products by trapping the acetone with an excess of semicarbazide. This improvement enables a better control of the reaction time, as the enzymatic reduction became rate determining. Greater than 75% of the product was identified as reduced cofactor by reverse-phase (RP) HPLC. Longer reaction led to decomposition of the product and lower yield. Purification was carried out by semipreparative RP HPLC followed by lyophilization and yielded a compound of high purity that was preserved at -80 degrees C. Applications of the new procedure to a wide variety of specific radioactivities ranging from carrier-free to a few Ci/mmol are discussed. The intriguing formation of radioactive NADP(+) by-product (the major product in some reported procedures), was also studied and minimized in the procedure described below. Finally, the usage of the labeled cofactor is demonstrated with the enzymes dihydrofolate reductase and thymidylate synthase.
Publication
Journal: American Journal of Chinese Medicine
April/7/2010
Abstract
Panax ginseng C A Meyer (PG) is one of the most popular qi-invigorating herbal medicine and has been used to promote health, vitality, and longevity in China. Although PG has been used in traditional Chinese medicine for millennia, its qi-invigorating activities still lack convincing evidence. We investigated the effects of Panax ginseng polysaccharide (PGP) on energy metabolism and mitochondrial protection. The chronic hypoxia model was set up. Lipid peroxidation product malondialdehyde (MDA) was assayed by thiobarbituric acid (TBA) colorimetry. Mice liver mitochondria were isolated by differential centrifugation. The spectrophotometric method was used to measure the swelling of mitochondria. The levels of adenosine triphosphate (ATP), adenosine diphosphate (ADP) and adenosine monophosphate (AMP) in liver cells were determined by reversed-phase high performance liquid chromatography (RP-HPLC), adenylate energy charge (AEC), total adenylate pool (TAP), ATP/ADP and ATP/AMP ratio were calculated. The creatine kinase (CK) activities in mice skeletal muscle were determined by a commercial monitoring kit. The result showed that PGP could inhibit mitochondrial injury and swelling induced by Fe(2+)-L-Cys in a concentration-dependent manner. PGP which was administered by oral gavage daily for 10 days could inhibit the formation of MDA in mice brain, increase levels of ATP, ADP, TAP and AEC, ratio of ATP/ADP and ATP/AMP in liver cells, increase CK activities in mice skeletal muscle under chronic hypoxia condition. These results indicate that PGP protect mitochondria by inhibiting mitochondrial swelling, and improving energy metabolism. PGP functions as a preventive antioxidant by increasing CK activities. Therefore, PGP had the pharmaceutical activities of antihypoxia, antioxidation and improving energy status.
Publication
Journal: European Journal of Radiology
January/9/2013
Abstract
OBJECTIVE
to evaluate the utility of (11)C-choline PET/CT in prostate cancer (PC) patients who have demonstrated a biochemical recurrence and a negative bone scintigraphy (BS).
METHODS
123 consecutive PC patients (mean age 67.6 years; range 54-83) with a biochemical relapse (mean PSA value 3.3ng/mL; range 0.2-25.5) after radical prostatectomy (RP) were included in our retrospective study. Patients underwent a BS that resulted negative and a (11)C-choline PET/CT within 4 months from BS (range: 1 day to 4 months; mean: 2.5 months). Validation of results was established by: (1) a positive biopsy, (2) a positive subsequent BS, CT or MR and (3) a normalization of (11)C-choline uptake after systemic therapy or a progression of the disease.
RESULTS
(11)C-choline PET/CT was positive in 42/123 patients (34.1%). (11)C-choline PET/CT detected lesions in: bone (10 patients), lymph-nodes (20 patients), bone and lymph nodes (7 patients), bone and lung (1 patient), lymph-nodes and lung (1 patient), local relapse (3 patients). Overall, (11)C-choline PET/CT showed a total of 30 unknown bone lesions in 18/123 (14.6%) patients.
CONCLUSIONS
(11)C-choline PET/CT showed a better sensitivity than BS in patients with biochemical relapse after RP: (11)C-choline PET/CT detected unknown bone lesions in 18/123 (14.6%) patients.
Publication
Journal: British Journal of Surgery
March/22/1989
Abstract
The anal canal in health is extremely sensitive to thermal stimuli, If temperature sensation plays a part in sensory discrimination two conditions must be fulfilled: there must be a temperature gradient along the anorectum and rectal contents must be able to come into contact with the sensitive anal mucosa. In a study of 53 normal subjects we demonstrated this temperature gradient with a median temperature difference between the rectum and lower, mid and upper anal canal of 0.4, 0.2 and 0.1 degrees C respectively. The second condition was examined in 15 normal ambulatory subjects by measuring mid-anal sphincter (SP) and rectal pressures (RP) with a microtransducer catheter. The signals were digitalized and recorded in a portable electronic memory for later computer display, and analysis. Marked spontaneous sphincter relaxation resulting in equalization of RP and SP occurred 7 times per hour (1-4). The conscious sensation of the presence of flatus was associated with an SP reduction of 30 mmHg (20-50 mmHg) and an RP increase of 7 mmHg (0-15 mmHg), such that RP greater than or equal to SP in 80 per cent of 144 recorded events. Using this new technique we have demonstrated the highly dynamic nature of the anal sphincter. Several times an hour the sphincter relaxes with subsequent equalization of rectal and anal pressures, allowing entry of rectal contents into the anal canal so that its presence and nature can be determined.
Publication
Journal: Journal of Agricultural and Food Chemistry
December/11/2007
Abstract
Corn gluten meal (CGM) was hydrolyzed by Alcalase after starch removal of CGM was applied as a pretreatment. A new inhibitory peptide for angiotensin I-converting enzyme (ACE) was isolated from the hydrolysate of CGM with the use of Bio-Rad P-2 gel filtration and followed by reverse-phase high-performance liquid chromatography (RP-HPLC). The sequence of the active peptide was determined to be Ala-Tyr after the application of amino acid analysis and HPLC/MS. The ICCE at 37 degrees C for 3 h. Ala-Tyr also exerted antihypertensive effects after oral administration to spontaneously hypertensive rats. A maximal reduction of systolic blood pressure of 9.5 mmHg was observed 2 h after oral administration of Ala-Tyr at doses of 50 mg/kg.
Publication
Journal: World Journal of Urology
October/21/2013
Abstract
OBJECTIVE
To evaluate the effect of total PSA (tPSA) and PSA kinetics on the detection rates of (11)C-Choline PET in patients with biochemical recurrence (BCR) after radical prostatectomy (RP) or external beam radiotherapy (EBRT).
METHODS
We included 185 patients with BCR after RP (PSA >0.2 ng/ml) or after EBRT (ASTRO definition). After injection of 400 MBq 11C-Choline i.v., a scan was made using the ECAT HR + PET camera with CT fusion images or Siemens mCT PET/CT. Biopsy-proven histology, confirmative imaging (CT or bone scan) and/or clinical follow-up (PSA) were used as composite reference. Statistical analysis was performed using PASW Statistics 18.
RESULTS
11C-Choline PET was positive in 124/185 cases (65%) (in 22/61 (36%) after RP, 102/124 (82%) after EBRT). In 79 patients a local recurrence was identified, and 45 patients showed locoregional metastases on PET/CT. In 20 cases a proven false-negative PET scan was observed. Positive PET scans were confirmed by histology in 87/124 (70%) cases, by confirmatory imaging in 34/124 (28%) and by clinical follow-up after salvage treatment in 3 (2%) cases. The ROC analysis to detect a recurrence showed significant difference in area under the curve (AUC) of tPSA 0.721(p < 0.001) and PSA velocity 0.730 (p < 0.001). PSA doubling time showed no significant difference with an AUC of 0.542 (p = 0.354). Detection rates are <50% in tPSA <2 ng/ml and/or PSA velocity <1 ng/ml/year.
CONCLUSIONS
Total serum PSA and PSA velocity have significant effect on the detection rates of 11C-Choline PET/CT in men with a BCR after RP or EBRT.
Publication
Journal: Journal of Applied Microbiology
April/9/2012
Abstract
OBJECTIVE
This work was conducted to identify the antifungal compounds produced by two previously isolated Bacillus sp. strains: ARP(2) 3 and MEP(2) 18. Both strains were subjected to further analysis to determine their taxonomic position and to identify the compounds responsible for their antifungal activity as well as to evaluate the efficiency of these strains to control sclerotinia stem rot in soybean.
RESULTS
The antifungal compounds were isolated by acid precipitation of cell-free supernatants, purified by RP-HPLC and then tested for antagonistic activity against Sclerotinia sclerotiorum. Mass spectra from RP-HPLC eluted fractions showed the presence of surfactin C(15) , fengycins A (C(16) -C(17)) and B (C(16)) isoforms in supernatants from strain ARP(2) 3 cultures, whereas the major lipopeptide produced by strain MEP(2) 18 was iturin A C(15) . Alterations in mycelial morphology and sclerotial germination were observed in the presence of lipopeptides-containing supernatants from Bacillus strains cultures. Foliar application of Bacillus amyloliquefaciens strains on soybean plants prior to S. sclerotiorum infection resulted in significant protection against sclerotinia stem rot compared with noninoculated plants or plants inoculated with a nonlipopeptide-producing B. subtilis strain.
CONCLUSIONS
Both strains, renamed as B. amyloliquefaciens ARP(2) 3 and MEP(2) 18, were able to produce antifungal compounds belonging to the cyclic lipopeptide family. Our data suggest that the foliar application of lipopeptide-producing B. amyloliquefaciens strains could be a promising strategy for the management of sclerotinia stem rot in soybean.
CONCLUSIONS
Sclerotinia stem rot was ranked as one of the most severe soybean disease in Argentina and worldwide. The results of this study showed the potential of B. amyloliquefaciens strains ARP(2) 3 and MEP(2) 18 to control plant diseases caused by S. sclerotiorum.
Publication
Journal: BJU International
July/15/2007
Abstract
OBJECTIVE
To evaluate and compare the role of (11)C-choline positron emission tomography (PET) and transrectal ultrasonography (TRUS) in the preoperative staging of clinically localized prostate cancer.
METHODS
Fifty-five consecutive patients with biopsy-confirmed prostate cancer had TRUS and (11)C-choline PET as a part of their clinical staging programme before radical retropubic prostatectomy (RP). The PET images were prospectively interpreted by a consensus decision of two nuclear medicine physicians and one radiologist with special expertise in the field. The TRUS was done by one experienced urologist. The criteria evaluated prospectively in each patient were extracapsular extension (ECE), seminal vesicle invasion (SVI) and bladder neck invasion (BNI). The results were compared with the histopathological findings after RP.
RESULTS
At pathology, 32 patients were classified pT2, 16 as pT3a and three had pT3b lesions. In four patients the histopathological examination showed pT4 with BNI. The overall accuracy of PET in defining local tumour stage (pT2 and pT3a-4) was 70%; the overall accuracy by TRUS was 26%. PET was more sensitive than TRUS for detecting ECE (pT3a) and SVI (pT3b) in advanced stages, and in pT4 stages. The sensitivity and positive predictive value (PPV) (95% confidence interval) in stages pT3a-pT4 for PET were 36 (17-59)% and 73 (39-89)%. The sensitivity and PPV in stages pT3a-pT4 for TRUS were 14 (3-35)% and 100 (29-100)%.
CONCLUSIONS
(11)C-choline PET and TRUS tended to understage prostate cancer. This series shows the current limited value of TRUS and PET for making treatment decisions in patients with clinically localized prostate cancer, especially if a nerve-sparing RP is considered. Treatment decisions should not be based on TRUS and (11)C-choline PET findings alone. In future studies, the combination of metabolic and anatomical information of PET and endorectal magnetic resonance imaging should be evaluated, as this might optimize the preoperative staging in prostate cancer.
Publication
Journal: Peptides
April/1/1997
Abstract
This study evaluates the nature of glycated human insulin formed following exposure to hyperglycemic conditions in vitro. Glycated insulin was purified by RP-HPLC and its molecular mass (5971.3 Da) determined by plasma desorption mass spectrometry (MS). The difference in mass (163.7 Da) from nonglycated insulin (5807.6 Da) corresponds to a single reduced glucose (glucitol) residue. Following reduction of insulin disulfide bridges, MS confirmed that the B-chain was glycated. Enzymatic digestions with trypsin, endoproteinase Glu-C, and thermolysin, followed by RP-HPLC and identification of fragments by MS, localized glycation to the B-chain (1-5) region. Electrospray tandem MS identified the site of glycation as the B-chain NH2-terminal Phe1 residue. This was confirmed by automated Edman degradation with glycated human insulin.
Publication
Journal: British Journal of Clinical Pharmacology
April/30/1997
Abstract
1. The influence of interferon-alpha (IFN alpha) on the clearances of theophylline (TH), antipyrine (AP) and hexobarbitone (HB) was studied in seven cancer patients given IFN alpha as their only treatment. In addition, IFN alpha effects on drug clearance were correlated with changes in serum inflammatory cytokines and acute phase proteins. 2. A 'baseline' study was performed by administering an oral drug 'cocktail' of TH (150 mg), AP (250 mg) and HB (250 mg) with saline injected simultaneously and again 24 h later. One week later, an 'acute' study was performed at the initiation of IFN alpha therapy, 3 x 10(6) units injected with the drug cocktail and again 24 h later. After 2 weeks of IFN alpha treatment three times per week, a 'chronic' study was performed with IFN alpha injected the day prior to, simultaneously with, as well as 24 h after the drug cocktail. 3. Plasma samples were collected over 48 h and the clearances of TH, AP and HB were estimated. Serum samples were collected at various times for the measurement of tumor necrosis factor (TNF), interleukin-1 (IL-1), interleukin-6 (IL-6), C-reactive protein (C-RP) and alpha 1-acid glycoprotein (AGP). 4. IFN alpha caused a 33% decrease in the oral clearance of TH during the chronic study compared with baseline (P < or = 0.05). Although IFN alpha inhibited TH clearance by 16% during the acute study and AP clearance by 20-21% during both acute and chronic studies, these changes did not reach statistical significance. IFN alpha caused minimal changes in HB clearance. There were no chronic effects of IFN alpha on serum cytokines or acute phase proteins. 5. The findings confirm that the most commonly used dose of IFN alpha inhibits the hepatic clearance in humans of some but not all drugs and that this inhibition persists during IFN alpha therapy. Because inhibition was not associated with increases in serum cytokines or acute phase proteins, the mechanism by which IFN alpha inhibits cytochrome P450 activities in vivo does not appear to involve inflammatory mediators such as TNF. IL-1 or IL-6.
Publication
Journal: American journal of physiology. Renal physiology
January/9/2011
Abstract
The renal outer medullary K(+) (ROMK) channel plays a critical role in renal sodium handling. Recent genome sequencing efforts in the Framingham Heart Study offspring cohort (Ji W, Foo JN, O'Roak BJ, Zhao H, Larson MG, Simon DB, Newton-Cheh C, State MW, Levy D, and Lifton RP. Nat Genet 40: 592-599, 2008) recently revealed an association between suspected loss-of-function polymorphisms in the ROMK channel and resistance to hypertension, suggesting that ROMK activity may also be a determinant of blood pressure control in the general population. Here we examine whether these sequence variants do, in fact, alter ROMK channel function and explore the mechanisms. As assessed by two-microelectrode voltage clamp in Xenopus oocytes, 3/5 of the variants (R193P, H251Y, and T313FS) displayed an almost complete attenuation of whole cell ROMK channel activity. Surface antibody binding measurements of external epitope-tagged channels and analysis of glycosylation-state maturation revealed that these variants prevent channel expression at the plasmalemma, likely as a consequence of retention in the endoplasmic reticulum. The other variants (P166S, R169H) had no obvious effects on the basal channel activity or surface expression but, instead, conferred a gain in regulated-inhibitory gating. As assessed in giant excised patch-clamp studies, apparent phosphotidylinositol 4,5-bisphosphate (PIP(2)) binding affinity of the variants was reduced, causing channels to be more susceptible to inhibition upon PIP(2) depletion. Unlike the protein product of the major ROMK allele, these two variants are sensitive to the inhibitory affects of a G protein-coupled receptor, which stimulates PIP(2) hydrolysis. In summary, we have found that hypertension resistance sequence variants inhibit ROMK channel function by different mechanisms, providing new insights into the role of the channel in the maintenance of blood pressure.
Publication
Journal: The American journal of physiology
August/22/1991
Abstract
The arterial system of mammals in the weight range from 0.6 to 70 kg is characterized by the three-element windkessel, a succinct representation of the arterial tree consisting of the parameters peripheral resistance (Rp), total arterial compliance (C), and aortic characteristic impedance (Zc). The values of these parameters in resting conditions are related to body mass (M). The time constant, or decay time (tau), of the arterial system (defining rate of decay of aortic pressure in diastole), the product of Rp and C, is also evaluated. The dependencies of the heart period (T, inverse of heart rate), and durations of ejection (Ts) and of diastole (Td) in resting conditions are also determined as a function of M. It is found that Rp = RpC = CRpCRp in all mammals. tau is related to M as tau = tau 0M+0.29; T and Td are related to M as T = T0M+0.27 and Td = Td0M+0.30, where tau 0, T0, and Td0 are proportionality constants. The duration of diastole is thus a constant fraction of T, and the ratios T/tau and Td/tau are independent of M. The findings indicate that arterial input impedance, normalized to aortic Zc and plotted as a function of frequency normalized to heart rate, is similar for all mammals. The finding that the ratio Td/tau is the same in mammals (and Ts/T and stroke volume/M are constant) explains the constancy of pulse pressure (systolic minus diastolic pressure).(ABSTRACT TRUNCATED AT 250 WORDS)
Publication
Journal: Journal of Physical Chemistry A
July/28/2011
Abstract
Phytochromes are red-light photoreceptor proteins that regulate a variety of responses and cellular processes in plants, bacteria, and fungi. The phytochrome light activation mechanism involves isomerization around the C(15)═C(16) double bond of an open-chain tetrapyrrole chromophore, resulting in a flip of its D-ring. In an important recent development, bacteriophytochrome (Bph) has been engineered for use as a fluorescent marker in mammalian tissues. Bphs covalently bind a biliverdin (BV) chromophore, naturally abundant in mammalian cells. Here, we report an ultrafast time-resolved mid-infrared spectroscopic study on the Pr state of two highly related Bphs from Rps. palustris , RpBphP2 (P2) and RpBphP3 (P3) with distinct photoconversion and fluorescence properties. We observed that the BV excited state of P2 decays in 58 ps, while the BV excited state of P3 decays in 362 ps. By combining ultrafast mid-IR spectroscopy with FTIR spectroscopy on P2 and P3 wild type and mutant proteins, we demonstrate that the hydrogen bond strength at the ring D carbonyl of the BV chromophore is significantly stronger in P3 as compared to P2. This result is consistent with the X-ray structures of Bph, which indicate one hydrogen bond from a conserved histidine to the BV ring D carbonyl for classical bacteriophytochromes such as P2, and one or two additional hydrogen bonds from a serine and a lysine side chain to the BV ring D carbonyl for P3. We conclude that the hydrogen-bond strength at BV ring D is a key determinant of excited-state lifetime and fluorescence quantum yield. Excited-state decay is followed by the formation of a primary intermediate that does not decay on the nanosecond time scale of the experiment, which shows a narrow absorption band at ∼1540 cm(-1). Possible origins of this product band are discussed. This work may aid in rational structure- and mechanism-based conversion of BPh into an efficient near-IR fluorescent marker.
Publication
Journal: PLoS ONE
December/6/2015
Abstract
USH2A mutations have been implicated in the disease etiology of several inherited diseases, including Usher syndrome type 2 (USH2), nonsyndromic retinitis pigmentosa (RP), and nonsyndromic deafness. The complex genetic and phenotypic spectrums relevant to USH2A defects make it difficult to manage patients with such mutations. In the present study, we aim to determine the genetic etiology and to characterize the correlated clinical phenotypes for three Chinese pedigrees with nonsyndromic RP, one with RP sine pigmento (RPSP), and one with USH2. Family histories and clinical details for all included patients were reviewed. Ophthalmic examinations included best corrected visual acuities, visual field measurements, funduscopy, and electroretinography. Targeted next-generation sequencing (NGS) was applied using two sequence capture arrays to reveal the disease causative mutations for each family. Genotype-phenotype correlations were also annotated. Seven USH2A mutations, including four missense substitutions (p.P2762A, p.G3320C, p.R3719H, and p.G4763R), two splice site variants (c.8223+1G>A and c.8559-2T>C), and a nonsense mutation (p.Y3745*), were identified as disease causative in the five investigated families, of which three reported to have consanguineous marriage. Among all seven mutations, six were novel, and one was recurrent. Two homozygous missense mutations (p.P2762A and p.G3320C) were found in one individual family suggesting a potential double hit effect. Significant phenotypic divergences were revealed among the five families. Three families of the five families were affected with early, moderated, or late onset RP, one with RPSP, and the other one with USH2. Our study expands the genotypic and phenotypic variability relevant to USH2A mutations, which would help with a clear insight into the complex genetic and phenotypic spectrums relevant to USH2A defects, and is complementary for a better management of patients with such mutations. We have also demonstrated that a targeted NGS approach is a valuable tool for the genetic diagnosis of USH2 and RP.
Publication
Journal: Toxicon
June/8/2005
Abstract
The increase in the emergence of antibiotic-resistant microorganisms and difficult to treat infections caused by these pathogens stimulate research aiming the identification of novel antimicrobials. Skin secretion of amphibian contains a large number of biologically active compounds, including compounds that performance defense mechanisms against microorganisms. In the present work, two antimicrobial bufadienolides, telocinobufagin (402.1609 Da) and marinobufagin (400.1515 Da), were isolated from skin secretions of the Brazilian toad Bufo rubescens. The specimens were collected in Brasilia (Distrito Federal, Brazil), the skin secretions extracted by electric stimulation, and submitted to purification by RP-HPLC. The molecular structure and mass determination were done by (1)H and (13)C NMR and mass spectrometry data, respectively. The antimicrobial activity was performed by liquid growth inhibition against Staphylococcus aureus and Escherichia coli. The minimum inhibitory concentrations of telocinobufagin and marinobufagin were, respectively, 64.0 and 16.0 microg/mL for E. coli and both 128 microg/mL for S. aureus. Besides the antimicrobial activity both bufadienolides promoted an increase of the contraction force in isolated frog ventricle strips.
Publication
Journal: Journal of Inflammation
August/15/2017
Abstract
Prostate is an immune-competent organ normally populated by inflammatory cells. Prostatic inflammation origin can be multi-factorial and there are some emerging evidences on its possible role as a factor involved in prostate cancer (PC) pathogenesis and progression. This review critically analyzes the role of inflammation as a prognostic factor for progression and aggressiveness of PC. We verified the last 10 years literature data on the association between inflammation and PC aggressiveness, or PC response to therapies. Several studies tried to correlate different inflammatory factors with the aggressiveness and metastatization of PC; all data sustain the role of inflammation in PC progression but they also produce confusion to identify a reliable clinical prognostic marker. Data on patients submitted to radical prostatectomy (RP) showed that cases with marked intraprostatic tissue inflammation are associated with higher rate of biochemical progression; systemic inflammation markers appear to have a significant prognostic value. Analyzing data on patients submitted to radiotherapy (RT) emerges a significant association between high neuthrophil to lymphocyte ratio (NLR) and decreased progression free survival and overall survival; also plateled to lymphocyte ratio (PLR) and C-reactive protein (CRP) have been proposed as significant prognostic factors for progression and overall survival. In patients submitted to androgen deprivation therapy (ADT), inflammation may drive castration resistant PC (CRPC) development by activation of STAT3 in PC cells. NLR has been proposed as independent predictor of overall survival in CRPC submitted to chemotherapy. Most of data are focused on markers related to systemic inflammation such as NLR and CRP, more than specifically to chronic prostatic inflammation. The suggestion is that these inflammatory parameters, also if not specific for prostatic inflammation and possibly influenced by several factors other than PC, can integrate with established prognostic factors.
Publication
Journal: Journal of Proteome Research
June/24/2004
Abstract
At present, mass spectrometry provides a rapid and sensitive means for making conclusive protein identifications from complex mixtures. Sequencing tryptic peptides derived from proteolyzed protein samples, also known as the "Bottom Up" approach, is the mass spectrometric gold standard for identifying unknowns. An alternative technology, "Top Down" characterization, is emerging as a viable option for protein identifications, which involves analyzing the intact unknowns for accurate mass and amino acid sequence tags. In this paper, both characterization methods were employed to more comprehensively differentiate two early-eluting peaks in a process-scale size-exclusion chromatography (SEC) step for a recombinant, immunoglobulin gamma-1 (IgG-1) fusion protein. The contents of each SEC peak were enzymatically digested, and the resulting peptides were mapped using reversed-phase (RP) HPLC-ion trap MS. Many low-level UV signals were observed among the fusion protein-related peptide peaks. These unknowns were collected, concentrated, and analyzed using nanoelectrospray (nanoES) collision-induced dissociation (CID) tandem (MS/MS) mass spectrometry for identification. The peptide sequencing experiments resulted in the identification of twenty host cell-related proteins. Following peptide mapping, the contents of the two SEC peaks were protein mass profiled using on-line RP HPLC coupled to a high-resolution, quadrupole time-of-flight (Qq/TOF) MS. Unknown proteins were also collected, concentrated, and dissociated using nanoES CID MS/MS. Intact protein CID experiments and accurate molecular weight information allowed for the identification of three full length host cell-derived proteins and numerous clips from these and additional proteins. The accurate molecular weight values allowed for the assignment of N- and C-terminal processing, which is difficult to conclusively access from peptide mapping data. The peptide-mapping experiments proved to be far more effective for making protein identifications from complex mixtures, whereas the protein mass profiling was useful for assessing modifications and distinguishing protein clips from full length species.
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