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1.
Among urinary organophosphorus pesticide (OP) metabolites, dialkyl phosphates (DAPs) have been most often measured as a sensitive biomarker in non-occupational and occupational OP exposure risk assessment. In our conventional method, we have employed a procedure including simple liquid–liquid extraction (diethyl ether/acetonitrile), derivatization (pentafluorobenzylbromide, PFBBr) and clean-up (multi-layer column) for gas chromatography–mass spectrometry (GC–MS) analysis starting from 5-mL urine samples. In this study, we introduce a revised analytical method for urinary DAPs; its main modification was aimed at improving the pre-derivatization dehydration procedure. The limits of detection were approximately 0.15 μg/L for dimethylphosphate (DMP), 0.07 μg/L for diethylphosphate (DEP), and 0.05 μg/L for both dimethylthiophosphate (DMTP) and diethylthiophosphate (DETP) in 2.5-mL human urine samples. Within-run precision (percent of relative standard deviation, %RSD) at the DAP levels varying in the range of 0.5–50 μg/L was 6.0–19.1% for DMP, 3.6–18.3% for DEP, 8.0–25.6% for DMTP and 9.6–27.8% for DETP. Between-run precision at 5 μg/L was below 15.7% for all DAPs. The revised method proved to be feasible to routine biological monitoring not only for occupational OP exposure but also for environmental background levels in the general population. Compared to our previous method, the revised method underscores the importance of adding pre-derivatization anhydration for higher sensitivity and precision.  相似文献   

2.
Measurement of organophosphorus (OP) pesticide metabolites in human biological fluids is an important biomarker of pesticides exposure. We measured the urinary excretion of OP pesticide metabolites to evaluate occupational and non-occupational exposure to OP pesticides in the Chinese population in Shanghai (Eastern China). We collected urine samples from 30 exposed workers in a dimethoate emulsion packing division and from 60 healthy adults without any report of occupational exposure. DMP, DMTP, DMDTP, DEP, DEDP and DEDTP were measured by GC-FPD after derivatization with pentafluorobenzyl bromide. The LOQ values (1 mL urine) were 2.0 μg/L for DMP and DETP, 4.0 μg/L for DEP and DEDTP, 8.0 μg/L for DMDTP, and 10.0 μg/L for DMTP. Dimethyl phosphates were detected in the majority of the urine samples, i.e., 90–100% in the exposed group and 80–87% in the control group. The concentration of the urinary diethyl phosphates DEP and DETP was above the LOQ values in 40 and 20% of samples for the exposed group, and in 50 and 30% of the samples for the control group, respectively. DEDTP was not detectable in the urine samples except for a post-shift exposed worker (detection frequency, 6.7%). Median creatinine-adjusted values (μg/g cr.) for DAP in Chinese with pre-shift, post-shift and without occupational exposure to OP were 316, 584 and 170 for DMP, below LOQ, 115 and 114 for DEP, 840, 1730 and 693 for DMTP, and 255, 756 and 135 for DMDTP, respectively. In all subjects, the highest excretion levels were found for DMTP. Several OP pesticide metabolites were frequently detected in urine samples of both populations studied.  相似文献   

3.
The aim of our study was to develop and validate an analytical approach for the quantitative determination of three dialkyl phosphate (DAP) metabolites, dimethyl phosphate (DMP), dimethyl thiophosphate (DMTP) and diethyl phosphate (DEP), of organophosphate pesticides (OPs) in hair samples. The proposed methodology comprises a decontamination step, solid–liquid extraction, followed by liquid–liquid extraction, pentafluorobenzyl bromide derivatization, clean-up on Florisil/PSA column and analysis by gas chromatography–mass spectrometry (GC-MS). Extraction recovery, obtained from 50?mg hair samples spiked at two concentration levels, ranged from 56.1 to 107.9% and the within-day precision ranged from 13.5 to 17.5%. Limits of detection (LODs) ranged from 0.02 to 0.10?ng mg?1. The results obtained from the analysis of hair samples of 30 agricultural workers show the suitability of the proposed method for monitoring people occupationally exposed to OPs. The most frequently detected compound was DEP followed by DMP. This is the first report on the detection of dialkyl phosphates in human hair which reflects the ability of hair testing to assess chronic exposure to OPs.  相似文献   

4.
In this study, we developed a safe and sensitive method for the simultaneous determination of urinary dialkylphosphates (DAPs), metabolites of organophosphorus insecticides (OPs), including dimethylphosphate (DMP), diethylphosphate (DEP), dimethylthiophosphate (DMTP), and diethylthiophosphate (DETP), using a pentafluorobenzylbromide (PFBBr) derivatization and gas chromatography-mass spectrometry (GC-MS). Several parameters were investigated: pH on evaporation, reaction temperature and time for the derivatization, the use of an antioxidant for preventing oxidation, and a clean-up step. The pH was set at 6, adjusted with K2CO3, and the reaction temperature and time of derivatization were 80 degrees C and 30 min, respectively. Sodium disulfite was chosen as an antioxidant. The clean-up step was performed with a Florisil/PSE mini-column to remove the unreacted PFBBr and sample matrix. This established procedure markedly shortened the sample preparation time to only about 3 h, and completely inhibited the unwanted oxidization of dialkylthiophosphates. The limits of determination (LOD) were approximately 0.3 microg/L for DMP, and 0.1 microg/L for DEP, DMTP, and DETP in 5 mL of human urine. Within-series and between-day imprecision for the present method using pooled urine spiked with DAPs was less than 20.6% in the calibration range of 1-300 microg/L, and the mean recovery was 56.7-60.5% for DMP, 78.5-82.7% for DEP, 88.3-103.9% for DMTP, and 84.2-92.4% for DETP. This method detected geometric mean values of the urinary DAPs in Japanese with and without occupational exposure to OPs, 16.6 or 27.4 for DMP, 1.0 or 0.7 for DEP, 1.3 or 2.3 for DMTP, and 1.0 or 1.1 microg/L for DETP, respectively. The present method, which does not require special equipment except for GC-MS, is quick, safe, and sensitive enough to be adopted in routine biological monitoring of non-occupational as well as occupational exposure to OPs.  相似文献   

5.
《Reproductive biology》2014,14(3):218-223
Hair analysis has been proposed as a minimally invasive technique capable of furnishing information regarding the stress response during medium- and long-term periods. Bristle samples were collected from the rump region of sows at three key physiological phases (before delivery – BD; weaning time – WT; pregnancy diagnosis – PD) during consecutive reproductive cycles in order to test swine hair as a reliable matrix of cortisol evaluation. Cortisol was extracted from the bristles and assayed using radioimmunoassay. The highest mean hair cortisol concentrations were demonstrated (p < 0.001) at the PD time points (20.1 ± .95 and 16.29 ± 2.15 pg/mg). Moreover, cortisol was significantly higher (p < 0.001) at BD2 (10.48 ± 0.96 pg/mg) as compared to BD1 (5.17 ± 0.51 pg/mg) and WT1 (6.01 ± 0.47 pg/mg). The various physiological phases had a significant effect on cortisol concentration (p < 0.00001) with a higher cortisol concentration found during late pregnancy and lactation than in early-mid pregnancy. This could be due not only to the physiological hormonal status, but also to the different housing conditions (single crates vs. group housing). The season of the year was also observed to have an effect (p < 0.005), with the lowest cortisol concentration recorded during the hot season.  相似文献   

6.
A series of 27 salicylanilide diethyl phosphates was prepared as a part of our on-going search for new antimicrobial active drugs. All compounds exhibited in vitro activity against Mycobacterium tuberculosis, Mycobacterium kansasii and Mycobacterium avium strains, with minimum inhibitory concentration (MIC) values of 0.5–62.5 μmol/L. Selected salicylanilide diethyl phosphates also inhibit multidrug-resistant tuberculous strains at the concentration of 1 μmol/L. Salicylanilide diethyl phosphates also exhibited mostly the activity against Gram-positive bacteria (MICs ⩾1.95 μmol/L), whereas their antifungal activity is significantly lower. The IC50 values for Hep G2 cells were within the range of 1.56–33.82 μmol/L, but there is no direct correlation with MICs for mycobacteria.  相似文献   

7.
Based on the presence of dialkyl phosphate moiety, we evaluated twenty-seven salicylanilide diethyl phosphates (diethyl [2-(phenylcarbamoyl)phenyl] phosphates) for the inhibition of acetylcholinesterase (AChE) from electric eel (Electrophorus electricus L.) and butyrylcholinesterase (BChE) from equine serum. Ellman’s spectrophotometric method was used. The inhibitory activity (expressed as IC50 values) was compared with that of the established drugs galantamine and rivastigmine. Salicylanilide diethyl phosphates showed significant activity against both cholinesterases with IC50 values from 0.903 to 86.3 μM. IC50s for BChE were comparatively lower than those obtained for AChE. All of the investigated compounds showed higher inhibition of AChE than rivastigmine, and six of them inhibited BChE more effectively than both rivastigmine and galantamine. In general, derivatives of 4-chlorosalicylic acid showed enhanced activity when compared to derivatives of 5-halogenated salicylic acids, especially against BChE. The most effective inhibitor of AChE was O-{5-chloro-2-[(3-bromophenyl)carbamoyl]phenyl} O,O-diethyl phosphate with IC50 of 35.4 μM, which is also one of the most potent inhibitors of BChE. O-{5-Chloro-2-[(3,4-dichlorophenyl)carbamoyl]phenyl} O,O-diethyl phosphate exhibited in vitro the strongest inhibition of BChE (0.90 μM). Salicylanilide diethyl phosphates act as pseudo-irreversible cholinesterases inhibitors.  相似文献   

8.
A method for determining a group of phthalic esters (PAEs) in physiological saline solutions has been developed. The PAEs studied were dimethyl phthalate, diethyl phthalate, butyl benzyl phthalate and dibutyl phthalate. These groups of phthalates were determined by liquid chromatography–electrospray ionization-tandem mass spectrometry, working in positive ion mode. The compounds were separated by liquid chromatography working in gradient mode with acetonitrile–ultrapure water as a mobile phase. The separation was performed starting with 5% of acetonitrile and increasing to 75% in 5 min, followed by isocratic elution for 8 min. The method was precise (with relative standard deviation (RSD) from 1.0 to 6.8%) and sensitive, with LODs of 0.05, 0.38, 0.05 and 0.82 μg L?1 for DMP, DEP, BBP and DBP, respectively. The proposed analytical method has been applied to determine these compounds in different physiological saline solutions commercialized in plastic bottles.  相似文献   

9.
Cancer cachexia is a multifactorial syndrome characterised by progressive weight loss, frequently accompanied by anorexia, sarcopenia, and chronic systemic inflammation. The white adipose tissue is markedly affected by cachexia and contributes to this syndrome throught the secretion of pro-inflammatory factors which reach the adjacent tissues and the circulation. A nonpharmacologic intervention that may attenuate cancer cachexia is chronic physical activity, but the effect of resistance training upon adipose tissue inflammation in cachexia has never been examined. For that purpose we designed a protocol in which animals were randomly assigned to a control group (CT, n = 7), a Tumour bearing group (TB, n = 7), a Resistance Trained group (RT, n = 7) and a Resistance Trained tumour bearing group (RTTB, n = 7). Trained rats climbed a vertical ladder with an extra load attached to the tail, representing 75–90% of total body mass, 3 times per week, for 8 weeks. In the 6th week of resistance training, tumour cells (3 × 107 Walker 256 carcinosarcoma) were inoculated in the tumour groups. Body, adipose tissue, muscle and tumour mass was determined, as well a blood biochemical parameters, and the hormone and cytokine profile assessed. The glycogen content of the liver and muscle was measured. IL-10, IL-6 and TNF-α protein expression was evaluated in the mesenteric adipose tissue (MEAT) examined. Resistance training increased by 9% body weight gain in RTTB (final weight 310.8 ± 9.8 g), when compared with TB (final weight 288.3 ± 4.9 g). LDL-c levels were decreased in RTTB (0.28 ± 0.9 mmol/L) by 43% when compared with TB (0.57 ± 0.1 mmol/L). HDL-c levels were increased in RTTB (1.31 ± 0.12 mmol/L) by 15% in regard to CT (1.13 ± 0.7 mmol/L) and 22% as compared with TB (1.07 ± 0.07 mmol/L). RTTB testosterone levels (577 ± 131 ng/mL) were 55% higher when compared with CT (254 ± 41.3 ng/mL) and 63% higher when compared with TB (221 ± 23.1 ng/mL). Adiponectin levels were augmented in RT (23 μg/mL) by 43% when compared with TB (11 μg/mL). Protein expression of IL-6 was increased 38% in TB MEAT (5.95 pg/μg), as compared with CT (3.64 pg/μg) and 50% compared with RTTB (2.91 pg/μg). Similar results with respect to TNF-α TB (7.18 pg/μg) were observed: 39% and 46%, higher protein expression in comparison with CT (4.63 pg/μg) and RTTB (3.8 pg/μg), respectively. IL-10 protein expression was found to be increased in TB (4.4 pg/μg) and RTTB (3.2 pg/μg) 50% and 47%, respectively, in comparison with CT (1.2 pu/μg). The IL-10/TNF-α ratio was higher in RTTB in relation to all others experimental groups. The results show a robust effect of resistance exercise training in preventing important symptoms of cancer cachexia, thus strongly suggesting it may appear as an alternative to endurance exercise as a non-pharmacological therapy in the management of this syndrome.  相似文献   

10.
Bacteria capable of using dimethyl phthalate (DMP) as the sole carbon and energy source were isolated from the sediments collected at a depth of 1340 m from the South China Sea. Sphingomonas yanoikuyae DOS01, identified based on 16S rRNA gene sequence, utilized DMP from an initial level of 180 mg l?1 to non-detectable in 35 h at 30 °C, the optical density (OD600) values increased over the time of incubation. Degradation intermediate monomethyl phthalate (MMP) accumulated up to 21.3 mg l?1 and then disappeared in the culture medium. When MMP or another intermediate phthalate (PA) was used as the sole substrate, this strain was only capable of degrading MMP, but not PA. Total organic carbon (TOC) analysis of the culture medium suggested that both DMP and MMP were mineralized, but not PA. This strain from the deep-ocean sediment transforms DMP to MMP using a common biochemical pathway for DMP as reported before. Further esterase activity assays indicated that the enzyme induced by MMP has higher affinity than that by DMP for the substrate p-nitrophenyl acetate. Our results indicated that complete degradation of DMP by this marine microorganism may involve a new biochemical pathway.  相似文献   

11.
In this study we report uranium analysis for human semen samples. Uranium quantification was performed by inductively coupled plasma mass spectrometry. No additives, such as chymotrypsin or bovine serum albumin, were used for semen liquefaction, as they showed significant uranium content. For method validation we spiked 2 g aliquots of pooled control semen at three different levels of uranium: low at 5 pg/g, medium at 50 pg/g, and high at 1000 pg/g. The detection limit was determined to be 0.8 pg/g uranium in human semen. The data reproduced within 1.4–7% RSD and spike recoveries were 97–100%. The uranium level of the unspiked, pooled control semen was 2.9 pg/g of semen (n = 10). In addition six semen samples from a cohort of Veterans exposed to depleted uranium (DU) in the 1991 Gulf War were analyzed with no knowledge of their exposure history. Uranium levels in the Veterans’ semen samples ranged from undetectable (<0.8 pg/g) to 3350 pg/g. This wide concentration range for uranium in semen is consistent with known differences in current DU body burdens in these individuals, some of whom have retained embedded DU fragments.  相似文献   

12.
Background & aims: The aim of this study was to investigate the clinical characteristics and pathophysiology of drug-induced liver injury (DILI) – acute liver failure (ALF). Methods: The patients with acute liver injury (ALI) including ALF from 2009 to 2014 were analyzed. The hepatic encephalopathy (HE) development rate was compared with the findings from a national survey in Japan. The serum cytokines levels and the findings of a liver function test were evaluated in the DILI patients. Results: The HE development rate substantially decreased for autoimmune hepatitis (AIH) – and undetermined cause-induced ALI owing to the early prediction system, but not in DILI-ALI. Among the DILI-ALF and AIH-ALF cases, the CK-18 fragment (1480.1 U/L, 3945.4 U/L), IL-8 (82.9 pg/mL, 207.5 pg/mL), IP-10 (1379.6 pg/mL, 3731.2 pg/mL) and MIP-1β (1017.7 pg/mL, 2273.3 pg/mL) levels were lower in the DILI-ALF cases. Among the DILI-ALI and DILI-ALF cases, IL-4 (19.8 pg/mL, 25.4 pg/mL) and RANTES (14028.0 pg/mL, 17804.7 pg/mL) were higher in DILI-ALI, and HMGB-1 (397.1 pg/μL, 326.2 pg/μL) and HGF (2.41 ng/mL, 0.55 ng/mL) were higher in DILI-ALF. We observed that HGF independently associated with DLI-ALF development. Conclusions: Despite the low grade apoptosis and inflammation, DILI patients progressed to ALF comparable with that of the AIH patients.  相似文献   

13.
Background: Active hexose correlated compound (AHCC) (a mixture of polysaccharides, amino acids, lipids and minerals derived from cultured mycelia of a Basidiomycete mushroom, Lentinula edodes) was used to assess amelioration of alopecia (hair loss) caused by cytosine arabinoside (Ara-C) and modulation of liver injury caused by single doses 6-mercaptopurine (6-MP) plus methotrexate (MTX). Methods: Follicular integrity and hair growth was assessed in male and female SD neonatal rats (8 days old) treated with a single dose of Ara-C (30 mg/kg/day, i.p.) and AHCC (500 mg/kg/day, p.o.) for 7 consecutive days. The side effects of a single oral dose of 6-MP (2.5 mg/kg body weight) plus MTX (30 mg/kg body weight) and their amelioration by treatment with AHCC (1000 mg/kg body weight) for 28 days were assessed in male ddY mice (8 weeks old). Results: Of the Ara-C treated rats 71.4% showed severe alopecia and 28.6% showed moderate alopecia. However, the AHCC (p.o.)-treated Ara-C group was significantly protected from alopecia. Ara-C treated rats had profound loss of hair follicles but the Ara-C plus AHCC-treated group had mild losses of follicles. AHCC supplementation to the 6-MP- and MTX-treated mice significantly increased body weight, erythrocytes, leukocytes and serum albumin, improved liver hypertrophy and degeneration, normalized the activities of serum glutamic oxaloacetic transaminase (sGOT) and serum glutamic pyruvic transaminase (sGPT), and enhanced liver drug-metabolizing enzymes. Conclusion: Co-administration of AHCC significantly reduced the side effects associated with Ara-C, 6-MP and MTX. However, the molecular mechanism for AHCC activity and its clinical integrity for use needs defining.  相似文献   

14.
Microalbuminuria is a predictor of adverse outcome in hypertension. We evaluated in vivo platelet activation, by urinary 11-dehydrothromboxane (TX)B2 and plasma P-selectin, in hypertensives with or without microalbuminuria, and its possible association with oxidative stress, by urinary 8-iso-prostaglandin (PG)F and endothelial dysfunction. Sixty essential hypertensive patients, with (n = 30) or without (n = 30) microalbuminuria, and 30 controls were studied. Endothelial function was assessed by nitric oxide products, intercellular adhesion molecule (ICAM)-1, and asymmetric dimethylarginine (ADMA) levels. Urinary 11-dehydro-TXB2 excretion was higher in microalbuminuric (median 805 pg/mg creatinine) compared to nonmicroalbuminuric patients or controls (414 and 291 pg/mg, respectively; P < 0.0001). Plasma P-selectin was significantly higher in patients with microalbuminuria (median 136 ng/ml) as compared to those without microalbuminuria or controls (85 and 65 ng/ml; P < 0.0001). Urinary 8-iso-PGF excretion was also enhanced in microalbuminuric (median 279 pg/mg creatinine) compared to nonmicroalbuminuric patients or controls (157 and 146 pg/mg, respectively; P < 0.0001). A significant impairment in endothelial function was found in microalbuminuric patients, with decreased nitric oxide and increased ICAM-1 and ADMA levels. Multivariate regression analysis showed that urinary 8-iso-PGF excretion (beta = 0.49; P < 0.0001) and microalbuminuria (beta = 0.36; P < 0.001) were independently related to 11-dehydro-TXB2 in hypertensives. Vitamin E supplementation (900 mg daily for 1 month) in 10 hypertensives with microalbuminuria was associated with normalization in median 11-dehydro-TXB2 and 8-iso-PGF. We conclude that lipid peroxidation is a major determinant of persistent platelet activation in hypertensive patients with microalbuminuria.  相似文献   

15.
A sensitive liquid chromatography–mass spectrometric method was validated for the quantification of RU38486 (mifepristone) in human and murine plasma. The analyte and internal standard (alfaxolone) were extracted by liquid–liquid extraction with diethyl ether, resolved on a C18 column using gradient elution with methanol and ammonium acetate and detected after positive electrospray ionization (m/z 430  372; m/z 333  297, respectively). Quantification was linear over the range 0.5–500 ng (r2 > 0.997), precise and accurate (intra-assay RSD  7.2%, RME  8.2%; inter-assay RSD  15.7% RME  10.2%). The limit of quantification (LOQ) was 50 pg injected on column, permitting reproducible analysis of RU38486 in small volumes of plasma.  相似文献   

16.
《Cytokine》2014,65(2):184-191
ObjectiveTriggering receptor expressed on myeloid cells-1 (TREM-1) is an important receptor involved in the innate inflammatory response and sepsis. We assessed soluble TREM-1 (sTREM-1) in 112 septic neonates (63 culture-positive and 49 culture-negative) and 40 healthy controls as a potential early diagnostic and prognostic marker for neonatal sepsis (NS).MethodsStudied neonates were evaluated for early- or late-onset sepsis using clinical and laboratory indicators upon admission. sTREM-1 was measured on initial sepsis evaluation and at 48 h after antibiotic therapy. For ethical reasons, cord blood samples were collected from control neonates and only samples from neonates that proved to be healthy by clinical examination and laboratory analysis were further analyzed for sTREM-1.ResultsBaseline sTREM-1 levels were significantly elevated in culture-proven (1461.1 ± 523 pg/mL) and culture-negative sepsis (1194 ± 485 pg/mL) compared to controls (162.2 ± 61 pg/mL) with no significant difference between both septic groups. Culture-positive or negative septic preterm neonates had significantly higher sTREM-1 compared to full term neonates. sTREM-1 was significantly higher in neonates with early sepsis than late sepsis and was associated with high mortality. sTREM-1 was significantly decreased 48 h after antibiotic therapy compared to baseline or levels in neonates with persistently positive cultures. sTREM-1 was positively correlated to white blood cells (WBCs), absolute neutrophil count, immature/total neutrophil (I/T) ratio, C-reactive protein (hs-CRP) and sepsis score while negatively correlated to gestational age and weight. hs-CRP and sepsis score were independently related to sTREM-1 in multiregression analysis. sTREM-1 cutoff value of 310 pg/mL could be diagnostic for NS with 100% sensitivity and specificity (AUC, 1.0 and 95% confidence interval [CI], 0.696–1.015) while the cutoff value 1100 pg/mL was predictive of survival with 100% sensitivity and 97% specificity (AUC, 0.978 and 95% CI, 0.853–1.13). However, hs-CRP cutoff 13.5 mg/L could be diagnostic for NS with a sensitivity of 76% and specificity of 72% (AUC, 0.762 and 95% CI, 0.612–0.925) and levels were not related to survival as no significant difference was found between dead and alive septic neonates.ConclusionsElevated sTREM-1 could be considered an early marker for NS that reflects sepsis severity and poor prognosis.  相似文献   

17.
《Hormones and behavior》2012,61(5):607-616
We hypothesize that beneficial effects of estradiol on cognitive performance diminish with age and time following menopause due to a progressive decline in basal forebrain cholinergic function. This study tested whether galanthamine, a cholinesterase inhibitor used to treat memory impairment associated with Alzheimer's disease, could enhance or restore estradiol effects on cognitive performance in aged rats that had been ovariectomized in middle-age. Rats were ovariectomized at 16–17 months of age. At 21–22 months of age rats began receiving daily injections of galanthamine (5 mg/day) or vehicle. After one week, half of each group also received 17ß-estradiol administered subcutaneously. Rats were then trained on a delayed matching to position (DMP) T-maze task, followed by an operant stimulus discrimination/reversal learning task. Treatment with galanthamine + estradiol significantly enhanced the rate of DMP acquisition and improved short-term delay-dependent spatial memory performance. Treatment with galanthamine or estradiol alone was without significant effect. Effects were task-specific in that galanthamine + estradiol treatment did not significantly improve performance on the stimulus discrimination/reversal learning task. In fact, estradiol was associated with a significant increase in incorrect responses on this task after reversal of the stimulus contingency. In addition, treatments did not significantly affect hippocampal choline acetyltransferase activity or acetylcholine release. This may be an effect of age, or possibly is related to compensatory changes associated with long-term cholinesterase inhibitor treatment. The data suggest that treating with a cholinesterase inhibitor can enhance the effects of estradiol on acquisition of a DMP task by old rats following a long period of hormone deprivation. This could be of particular benefit to older women who have not used hormone therapy for many years and are beginning to show signs of mild cognitive impairment. Potential mechanisms for these effects are discussed.  相似文献   

18.
Background and ObjectiveHigh parathyroid hormone (PTH) concentrations are associated with increased bone resorption and bone matrix degradation. Some studies show elevated PTH concentrations and hypocalcemia in patients with advanced prostate carcinoma, although the pathophysiological significance of these findings is not well defined.Materials and methodsWe performed a retrospective study of 60 patients diagnosed with advanced prostate cancer (44 nonmetastatic and 16 metastatic) treated with androgen deprivation. In all patients, PTH, calcium, phosphorus, 25 (OH) vitamin D and prostate-specific antigen (PSA) were determined. Bone scintigraphy had previously been performed.ResultsIn patients with bone metastases, mean concentrations were as follows: calcium 9.19 mg/dl, phosphorus 3.47 mg/dl, 25 (OH) vitamin D 13.85 ng/ml, PTH 66.8 pg/ml and total PSA 101.27 ng/ml. For those without bone metastases, the results were calcium 9.39 mg/dl, phosphorus 3.38 mg/dl, 25 (OH) vitamin D 20.50 ng/ml, PTH 52.23 pg/ml and total PSA 2.52 ng/ml. PTH levels were significantly higher in patients with prostate cancer and bone metastases than in those without metastases (p=0.03). Vitamin D levels were also significantly lower in this group (p=0.03). There were no differences in other values.ConclusionsThe present study found increased PTH concentrations in patients with advanced prostate cancer. This finding could be useful to predict disease progression.  相似文献   

19.
To evaluate the therapeutic efficacy of high-dose octreotide in patients with predicted severe acute pancreatitis (SAP) or SAP, two hundred and thirty-six patients with predicted SAP and 136 patients with SAP were randomized into control, high-dose octreotide (High-O) and low-dose octreotide (Low-O) groups. In addition to the conventional managements administrated in control group, High-O group received an intravenous infusion of octreotide at 50 μg/h × 3d + 25 μg/h × 4d, and Low-O group received octreotide at 25 μg/h × 7d. The major primary outcomes included the numbers of predicted SAP patients which developed SAP after intervention and the number of patients with SAP amelioration. Secondary outcomes included APACHE II, SIRS scores, plasma levels of somatostatin (SST), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6). There were no significant differences between the control and Low-O groups in terms of prevention and treatment for SAP. The incidence of SAP in patients with predicted SAP who received High-O was significantly lower than the Low-O group: 37.5% vs. 59.8%, p = 0.005. Compared with Low-O group, the number of SAP patients in the SAP arm in the High-O group was reduced by 29.8%. Plasma levels of SST in both predicted SAP and the SAP patients were efficiently recovered (from 132.71 ± 31.40 pg/ml to 180.00 ± 23.50 pg/ml, p < 0.05) after high-dose octreotide supplementation, which concomitantly reduced TNF-α and IL-6 levels. High-dose octreotide administration within 48 h after AP onset may efficiently reduce the risk of SAP developing and partly attenuate SAP through raising plasma SST to a normal level and decreasing IL-6 and TNF-α.  相似文献   

20.
Melatonin is an important antioxidant, and through its anti-inflammatory effects it can control immune responses, oxidative stress, and defense cell infiltration. Periodontitis is a disease of the oral cavity and the generation of free radicals is an important consideration in this disease. Therefore, we examined the immune-modulatory and antioxidant roles of melatonin in the treatment of periodontitis. In all, 30 male Wistar rats were randomly divided into three groups: the control group, the periodontitis-induced (PED) group, and the periodontitis+melatonin treatment (MEL+PED) group. The control group received no treatment, whereas periodontitis was induced in both the PED and the MEL+PED groups, with the MEL+PED group being treated with systemic melatonin. For the periodontitis-induced groups, the rats' mandibular first molar teeth were ligatured (3-0 cotton) in a submarginal position for 4 weeks, and then the ligature was removed. After removal of the ligature, melatonin was administered only to the MEL+PED group (an ip dose of 10 mg/kg body wt for 15 days at 11:00 PM each day). In the histological examination, the MEL+PED group, which received the melatonin, showed reduced inflammatory cytokines (IL-1β, from 97.47 to 84.24 pg/ml; TNF-α, from 0.22530 to 0.22519 pg/ml), regulated oxidative stress parameters (MDA, from 41,458 to 30,708 nmol/g; GSH, from 18,166 to 25,858 nmol/mg), and less periodontal tissue destruction (CEJ-PL, lingual, from 244.54 to 140.57 μm; buccal, from 235.6 to 158.93 μm; and CEJ-BC, lingual, from 383.65 to 287.76 μm; buccal, from 391.92 to 296.12 μm). From these findings we conclude that, even when periodontitis was induced, melatonin reduced the oxidative damage in the rats' periodontal tissue by inhibiting the inflammatory effects and by restoring the antioxidants.  相似文献   

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