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1.
Clonorchis sinensis is a biological carcinogen inducing human cholangiocarcinoma, and clonorchiasis is one of the important endemic infectious diseases in East Asia. The present study investigated survival longevity of C. sinensis adult worms in various in vitro conditions to find the best way of keeping the worms longer. The worms were maintained in 0.85% NaCl, 1×PBS, 1×Locke''s solution, RPMI-1640, DMEM, and IMDM media, and in 1×Locke''s solution with different supplements. All of the worms died within 3 and 7 days in 0.85% NaCl and 1×PBS, respectively, but survived up to 57 days in 1×Locke''s solution. The worms lived for 106 days in DMEM, and 114 days in both RPMI-1640 and IMDM media. The survival rate in RPMI-1640 medium was the highest (50%) compared to that in DMEM (20±10%) and in IMDM (33.3±25.2%) after 3 months. The 1×Locke''s solution with 0.005% bovine bile supplement showed increased duration of maximum survival from 42 days to 70 days. Higher concentration of bile supplements than 0.005% or addition of glucose were disadvantageous for the worm survival. The worms died rapidly in solutions containing L-aspartic acid, L-glutamic acid, and adenine compared to L-arginine, L-serine, and L-tryptophan. In conclusion, the 1×Locke''s solution best supports the worms alive among inorganic solutions for 57 days, and the RPMI-1640 medium maintains living C. sinensis adults better and longer up to 114 days in vitro than other media.  相似文献   

2.

Background

Schistosomes are chronic intravascular helminth parasites of humans causing a heavy burden of disease worldwide. Diagnosis of schistosomiasis currently requires the detection of schistosome eggs in the feces and urine of infected individuals. This method unreliably measures disease burden due to poor sensitivity and wide variances in egg shedding. In vivo imaging of schistosome parasites could potentially better assess disease burden, improve management of schistosomiasis, facilitate vaccine development, and enhance study of the parasite''s biology. Schistosoma mansoni (S. mansoni) have a high metabolic demand for glucose. In this work we investigated whether the parasite burden in mice could be assessed by positron emission tomography (PET) imaging with 2-deoxy-2[18F]fluoro-D-glucose (FDG).

Methodology/Principal Findings

Live adult S. mansoni worms FDG uptake in vitro increased with the number of worms. Athymic nude mice infected with S. mansoni 5–6 weeks earlier were used in the imaging studies. Fluorescence molecular tomography (FMT) imaging with Prosense 680 was first performed. Accumulation of the imaging probe in the lower abdomen correlated with the number of worms in mice with low infection burden. The total FDG uptake in the common portal vein and/or regions of elevated FDG uptake in the liver linearly correlated to the number of worms recovered from infected animals (R2 = 0.58, P<0.001, n = 40). FDG uptake showed a stronger correlation with the worm burden in mice with more than 50 worms (R2 = 0.85, P<0.001, n = 17). Cryomicrotome imaging confirmed that most of the worms in a mouse with a high infection burden were in the portal vein, but not in a mouse with a low infection burden. FDG uptake in recovered worms measured by well counting closely correlated with worm number (R2 = 0.85, P<0.001, n = 21). Infected mice showed a 32% average decrease in total FDG uptake after three days of praziquantel treatment (P = 0.12). The total FDG uptake in untreated mice increased on average by 36% over the same period (P = 0.052).

Conclusion

FDG PET may be useful to non-invasively quantify the worm burden in schistosomiasis-infected animals. Future investigations aiming at minimizing non-specific FDG uptake and to improve the recovery of signal from worms located in the lower abdomen will include the development of more specific radiotracers.  相似文献   

3.
Opisthorchis viverrini and Clonorchis sinensis are parasites known to be carcinogenic and causative agents of cholangiocarcinoma in Asia. The standard method for diagnosis for those parasite infections is stool examination to detect parasite eggs. However, the method has low sensitivity, and eggs of O. viverrini and C. sinensis are difficult to distinguish from each other and from those of some other trematodes. Here, we report a multiplex real-time PCR coupled with high resolution melting (HRM) analysis for the differentiation of O. viverrini and C. sinensis eggs in fecal samples. Using 2 pairs of species-specific primers, DNA sequences from a portion of the mitochondrial NADH dehydrogenase subunit 2 (nad 2) gene, were amplified to generate 209 and 165 bp products for O. viverrini and C. sinensis, respectively. The distinct characteristics of HRM patterns were analyzed, and the melting temperatures peaked at 82.4±0.09℃ and 85.9±0.08℃ for O. viverrini and C. sinensis, respectively. This technique was able to detect as few as 1 egg of O. viverrini and 2 eggs of C. sinensis in a 150 mg fecal sample, which is equivalent to 7 and 14 eggs per gram of feces, respectively. The method is species-specific, rapid, simple, and does not require fluorescent probes or post-PCR processing for discrimination of eggs of the 2 species. It offers a new tool for differentiation and detection of Asian liver fluke infections in stool specimens.  相似文献   

4.
Two DCM mutants (E40K and E54K) of tropomyosin (Tm) were examined using the thin-filament extraction/reconstitu­tion technique. The effects of the Ca2+, ATP, phos­phate (Pi), and ADP concentrations on isometric tension and its transients were studied at 25°C, and the results were com­pared to those for the WT protein. Our results indicate that both E40K and E54K have a significantly lower T HC (high Ca2+ ten­sion at pCa 4.66) (E40K: 1.21±0.06 T a, ±SEM, N = 34; E54K: 1.24±0.07 T a, N = 28), a significantly lower T LC (low- Ca2+ tension at pCa 7.0) (E40K: 0.07±0.02 T a, N = 34; E54K: 0.06±0.02 T a, N = 28), and a significantly lower T act (Ca2+ activatable tension) (T act = T HC–TLC, E40K: 1.15±0.08 T a, N = 34; E54K: 1.18±0.06 T a, N = 28) than WT (T HC = 1.53±0.07 T a, T LC = 0.12±0.01 T a, T act = 1.40±0.07 T a, N = 25). All tensions were normalized to T a ( = 13.9±0.8 kPa, N = 57), the ten­sion of actin-filament reconstituted cardiac fibers (myocardium) under the standard activating conditions. The Ca2+ sensitivity (pCa50) of E40K (5.23±0.02, N = 34) and E54K (5.24±0.03, N = 28) was similar to that of the WT protein (5.26±0.03, N = 25). The cooper­a­tivity increased significantly in E54K (3.73±0.25, N = 28) compared to WT (2.80±0.17, N = 25). Seven kinetic constants were deduced using sinusoidal analysis at pCa 4.66. These results enabled us to calculate the cross-bridge distribution in the strongly attached states, and thereby deduce the force/cross-bridge. The results indicate that the force/cross-bridge is ∼15% less in E54K than WT, but remains similar to that of the WT protein in the case of E40K. We conclude that over-inhibition of the actomyosin interaction by E40K and E54K Tm mutants leads to a decreased force-generating ability at systole, which is the main mechanism underlying the early pathogenesis of DCM.  相似文献   

5.

Objective

To compare the effects of transcatheter arterial chemoembolization (TACE) with transcatheter arterial embolization (TAE) on liver function, hepatic damage, and hepatic fibrogenesis in a rabbit tumor model.

Materials and Methods

Thirty-nine New Zealand white rabbits implanted with VX2 tumors in the left liver lobes were randomly divided into three groups: TAE, TACE, and control group. In the TAE group (n = 15), polyvinyl alcohol particles (PVAs) were used for left hepatic artery embolization. In the TACE group (n = 15), the tumors were treated with left hepatic arterial infusions of a suspension of 10-hydroxycamptothecin and lipiodol, followed by embolization with PVAs. In the control group (n = 9), the animals received sham treatment with distilled water. Serum and liver samples were collected at 6 hours, 3 days and 7 days after treatment. Liver damage was measured using a liver function test and histological analyses. Liver fibrogenesis and hepatic stellate cell (HSC) activation were evaluated using Sirius Red and anti-alpha-smooth muscle actin (α-SMA) immunohistochemical stains.

Results

TACE caused liver injury with greater increases in serum alanine aminotransferase and aspartate aminotransferase levels on day 3 (P<0.05). Histological analyses revealed increased hepatic necrosis in adjacent non-tumorous liver tissue from day 3 compared to the TAE group (Suzuki score of 2.33±1.29 versus 1.13±1.18, P = 0.001). HSC activation and proliferation were significantly increased in the TACE group compared to the control group at 3 and 7 days after treatment (0.074±0.014 vs. 0.010±0.006, and 0.088±0.023 vs. 0.017±0.009, P<0.05). Sirius Red staining demonstrated a statistically significant increase in collagen deposition in the livers in the TACE group 7 days after embolization compared to the control group (0.118±0.012 vs. 0.060±0.017, P = 0.05).

Conclusion

The results of this animal study revealed that TACE induced prominent hepatocellular damage and hepatic fibrogenesis, which compromised liver function and may be responsible for chronic liver decompensation.  相似文献   

6.

Purpose

To investigate the morphology of corneal caps in femtosecond laser small incision lenticule extraction (SMILE) and its relation to the refractive outcomes.

Methods

A prospective study of fifty-four corneal caps created with VisuMax femtosecond laser were examined using an Fourier-domain optical coherence tomography at 1 day, 1 week, 1 month and 6 months after SMILE. The cap thickness at nine points on each of the four meridians (0°, 45°, 90°, 135°) and the diameter were measured. Cap morphology, changes over time and its correlation with refractive outcomes were assessed.

Results

The mean achieved central cap thickness were (108.74±5.06) µm at 6 months and (107.32±4.81 ) µm at 1 month postoperatively, significantly thinner than that at 1 day (110.81±7.95) µm and 1 week (109.58±7.48 ) µm (P<0.05). The mean diameter on 0° meridian was (7.61±0.07) mm, significantly larger than that on 90° meridian (7.57±0.06) mm (P = 0.001). Cap morphology showed good regularity, except that the differences of points in two pairs were significant at 1 day postoperatively. The uniformity was consistent over time and the central cap thickness was thinner than those in the paracentral and peripheral areas. The refractive outcomes stabilized within 1 month. Uncorrected distance visual acuity (UDVA) was correlated to the central cap thickness at 1 day and 1 week (both rs = 0.33, p<0.05). The uniformity index was correlated with UDVA (rs = 0.34, p<0.05) and corrected distance visual acuity (rs = 0.32, p<0.05) at 1 week postoperatively.

Conclusions

Corneal caps of SMILE are predictable with good reproducibility, regularity and uniformity. Cap morphology might have a mild effect on refractive outcomes in the early stage. Further study should focus on the impact on the visual quality.  相似文献   

7.

Background

Stool examination by counting eggs per gram of feces (EPGs) is the best method to estimate worm burden of Clonorchis sinensis in infected humans. The present study investigated a correlation between EPGs and worm burden in human clonorchiasis.

Methods and Findings

A total of 60 residents, 50 egg-positive and 10 egg-negative, in Sancheong-gun, Korea, participated in this worm collection trial in 2006–2009. They were diagnosed by egg positivity in feces using the Kato-Katz method. After administration of praziquantel, they were purged with cathartics on the next day, and then discharged adult worms were collected from their feces. Their EPGs ranged from 0 to 65,544. Adult worms of C. sinensis were collected from 17 egg-positive cases, and the number of worms ranged from 1 to 114 in each individual. A positive correlation between EPGs and numbers of worms was demonstrated (r = 0.681, P<0.001). Worm recovery rates were 9.7% in cases of EPGs 1–1,000 and 73.7% in those of EPGs over 1,000. No worms were detected from egg-negative subjects. Maximum egg count per worm per day was roughly estimated 3,770 in a subject with EPGs 2,664 and 106 collected worms.

Conclusions

The numbers of the worms are significantly correlated with the egg counts in human clonorchiasis. It is estimated that at least 110 worms are infected in a human body with EPGs around 3,000, and egg productivity of a worm per day is around 4,000.  相似文献   

8.
In this study, the in vitro effects of amodiaquine (AQ) monotherapy on the egg output of paired adult Schistosoma mansoni worms and their survival during in vitro culture were assessed. In addition, the gross morphological alterations of male and female worms caused by AQ were visually observed under a dissecting microscope. AQ significantly reduced the daily egg output of paired adult S. mansoni worms following incubation for 14 days at 1-5 µg/mL, but not at 0.5 µg/mL, compared with the control group. AQ also reduced the survival of male and female worms at concentrations of 2 and 5 µg/mL, respectively. Moreover, exposure to 5 µg/mL AQ caused severe swelling and/or localisation of black content in the body of all male and female worms within one or two days of incubation; subsequently, shrinkage in the male worms and elongation in the female worms were observed. The initial morphological alterations caused by AQ occurred along the intestinal tract of the male and female worms. To our knowledge, this is the first study to report not only the efficacy of AQ at concentrations lower than 5 µg/mL on paired adult S. mansoni worms, but also the effects of AQ on the intestinal tracts of worms in in vitro culture.  相似文献   

9.

Background

To determine whether the use of idarubicin+cytarabine (IA) is more effective than the use of daunorubicin+cytarabine (DA) as induction chemotherapy for patients with newly diagnosed acute myeloid leukaemia.

Methods

A computer-based search was performed. Randomised trials comparing IA with DA as induction therapy for newly diagnosed AML were included in this meta-analysis. The primary outcome of interest for our analysis was survival (disease-free survival, event-free survival and overall survival); the secondary endpoint was complete remission.

Results

Ten trials with 4,060 patients were eligible for this meta-analysis. Our pooled results suggest that IA is associated with a significant advantage in CR (RR = 1·23; 95% CI = 1·07–1·41, p = 0.004), EFS (HR = 0·64; 95% CI = 0·45–0·91, p = 0.013), and OS (HR = 0·88; 95% CI = 0·81–0·95, p = 0.02) but not in DFS (HR = 0·90; 95% CI = 0·80–1·00, p = 0.06). In the subgroup analysis, age had a significant interaction with OS and CR benefits.

Conclusion

Our analysis indicated that IA could improve the duration of overall survival compared to DA as induction therapy for young patients with newly diagnosed AML. Further study is needed to determine whether IA can produce clinical benefits in selected genetic or molecular subgroups of young AML patients.  相似文献   

10.
While Trypanosoma cruzi, the etiologic agent of Chagas disease, is typically vector-borne, infection can also occur through solid organ transplantation or transfusion of contaminated blood products. The ability of infected human cells, tissues, and cellular and tissue-based products (HCT/Ps) to transmit T. cruzi is dependent upon T. cruzi surviving the processing and storage conditions to which HCT/Ps are subjected. In the studies reported here, T. cruzi trypomastigotes remained infective 24 hours after being spiked into blood and stored at room temperature (N = 20); in 2 of 13 parasite-infected cultures stored 28 days at 4°C; and in samples stored 365 days at −80°C without cryoprotectant (N = 28), despite decreased viability compared to cryopreserved parasites. Detection of viable parasites after multiple freeze/thaws depended upon the duration of frozen storage. The ability of T. cruzi to survive long periods of storage at +4 and −80°C suggests that T. cruzi-infected tissues stored under these conditions are potentially infectious.  相似文献   

11.
Adrenocortical carcinoma (ACC) is a rare, but highly malignant tumor of unknown origin. Inhibin α-subunit (Inha) knockout mice develop ACCs following gonadectomy. In man, INHA expression varies widely within ACC tissues and its circulating peptide inhibin pro-αC has been described as a novel tumor marker for ACC. We investigated whether genetic and epigenetic changes of the INHA gene in human ACC cause loss or variation of INHA expression. To this end, analyses of INHA sequence, promoter methylation and mRNA expression were performed in human adrenocortical tissues. Serum inhibin pro-αC levels were also measured in ACC patients. INHA genetic analysis in 37 unique ACCs revealed 10 novel, heterozygous rare variants. Of the 3 coding bases affected, one variant was synonymous and two were missense variants: S72F and S184F. The minor allele of rs11893842 at −124 bp was observed at a low frequency (24%) in ACC samples and was associated with decreased INHA mRNA levels: 4.7±1.9 arbitrary units for AA, compared to 26±11 for AG/GG genotypes (P = 0.034). The methylation of four proximal INHA promoter CpGs was aberrantly increased in five ACCs (47.7±3.9%), compared to normal adrenals (18.4±0.6%, P = 0.0052), whereas the other 14 ACCs studied showed diminished promoter methylation (9.8±1.1%, P = 0.020). CpG methylation was inversely correlated to INHA mRNA levels in ACCs (r = −0.701, p = 0.0036), but not associated with serum inhibin pro-αC levels. In conclusion, aberrant methylation and common genetic variation in the INHA promoter occur in human ACCs and are associated with decreased INHA expression.  相似文献   

12.
Differentiation of the fish-borne trematodes belonging to the Opisthorchiidae, Heterophyidae and Lecithodendriidae is important from a clinical and epidemiological perspective, yet it is impossible to do using conventional coprological techniques, as the eggs are morphologically similar. Epidemiological investigation therefore currently relies on morphological examination of adult worms following expulsion chemotherapy. A PCR test capable of amplifying a segment of the internal transcribed spacer region of ribosomal DNA for the opisthorchiid and heterophyid flukes eggs taken directly from faeces was developed and evaluated in a rural community in central Thailand. The lowest quantity of DNA that could be amplified from individual adults of Opisthorchis viverrini, Clonorchis sinensis and Haplorchis taichui was estimated at 0.6 pg, 0.8 pg and 3 pg, respectively. The PCR was capable of detecting mixed infection with the aforementioned species of flukes under experimental conditions. A total of 11.6% of individuals in rural communities in Sanamchaikaet district, central Thailand, were positive for ‘Opisthorchis-like’ eggs in their faeces using conventional parasitological detection techniques. In comparison to microscopy, the PCR yielded a sensitivity and specificity of 71.0% and 76.7%, respectively. Analysis of the microscopy-positive PCR products revealed 64% and 23% of individuals to be infected with O. viverrini and C. sinensis, respectively. The remaining 13% (three individuals) were identified as eggs of Didymozoidae, presumably being passed mechanically in the faeces following the ingestion of infected fishes. An immediate finding of this study is the identification and first report of a C. sinensis–endemic community in central Thailand. This extends the known range of this liver fluke in Southeast Asia. The PCR developed herein provides an important tool for the specific identification of liver and intestinal fluke species for future epidemiological surveys.  相似文献   

13.
It is classically thought that increases in hemoglobin mass (Hbmass) take several weeks to develop upon ascent to high altitude and are lost gradually following descent. However, the early time course of these erythropoietic adaptations has not been thoroughly investigated and data are lacking at elevations greater than 5000 m, where the hypoxic stimulus is dramatically increased. As part of the AltitudeOmics project, we examined Hbmass in healthy men and women at sea level (SL) and 5260 m following 1, 7, and 16 days of high altitude exposure (ALT1/ALT7/ALT16). Subjects were also studied upon return to 5260 m following descent to 1525 m for either 7 or 21 days. Compared to SL, absolute Hbmass was not different at ALT1 but increased by 3.7±5.8% (mean ± SD; n = 20; p<0.01) at ALT7 and 7.6±6.6% (n = 21; p<0.001) at ALT16. Following descent to 1525 m, Hbmass was reduced compared to ALT16 (−6.0±3.7%; n = 20; p = 0.001) and not different compared to SL, with no difference in the loss in Hbmass between groups that descended for 7 (−6.3±3.0%; n = 13) versus 21 days (−5.7±5.0; n = 7). The loss in Hbmass following 7 days at 1525 m was correlated with an increase in serum ferritin (r = −0.64; n = 13; p<0.05), suggesting increased red blood cell destruction. Our novel findings demonstrate that Hbmass increases within 7 days of ascent to 5260 m but that the altitude-induced Hbmass adaptation is lost within 7 days of descent to 1525 m. The rapid time course of these adaptations contrasts with the classical dogma, suggesting the need to further examine mechanisms responsible for Hbmass adaptations in response to severe hypoxia.  相似文献   

14.
To evaluate the effects of pesticides to parasite eggs, Ascaris suum eggs were incubated with 5 different pesticides (1:1,500-1:2,000 dilutions of 2% emamectin benzoate, 5% spinetoram, 5% indoxacarb, 1% deltamethrin, and 5% flufenoxuron; all v/v) at 20℃ for 6 weeks, and microscopically evaluated the egg survival and development on a weekly basis. The survival rate of A. suum eggs incubated in normal saline (control eggs) was 90±3% at 6 weeks. However, the survival rates of eggs treated with pesticides were 75-85% at this time, thus significantly lower than the control value. Larval development in control eggs commenced at 3 weeks, and 73±3% of eggs had internal larvae at 6 weeks. Larvae were evident in pesticide-treated eggs at 3-4 weeks, and the proportions of eggs carrying larvae at 6 weeks (36±3%-54±3%) were significantly lower than that of the control group. Thus, pesticides tested at levels similar to those used in agricultural practices exhibited low-level ovicidal activity and delayed embryogenesis of A. suum eggs, although some differences were evident among the tested pesticides.  相似文献   

15.
PurposeThe Glaucoma Stereo Analysis Study (GSAS), a cross sectional multicenter collaborative study, used a stereo fundus camera to assess various morphological parameters of the optic nerve head (ONH) in glaucoma patients and investigated the relationships between these parameters and patient characteristics.ResultsPatient characteristics included refractive error of −3.38±3.75 diopters, intraocular pressure (IOP) of 13.6±2.6 mmHg, and visual field mean deviation (MD) of −4.71±3.26 dB. Representative ONH parameters included a horizontal disc width of 1.66±0.28 mm, vertical disc width of 1.86±0.23 mm, disc area of 2.42±0.63 mm2, cup area of 1.45±0.57 mm2, and cup volume of 0.31±0.22 mm3. Correlation analysis revealed significant negative associations between vertical cup-to-disc ratio (0.82±0.08) and MD (r = −0.40, P<0.01) and between disc tilt angle (10.5±12.5 degrees) and refractive error (r = −0.36, P<0.01). Seventy-five percent of the eyes had a positive value for rim decentering (0.30±0.42), indicating that rim thinning manifested more often as an inferior lesion than a superior lesion.ConclusionWe used stereoscopic analysis to establish a database of ONH parameters, which may facilitate future studies of glaucomatous changes in ONH morphology.  相似文献   

16.
The objective of this study was to assess the possible modifications due to amoxicillin-clavulanic acid (AMC) treatment on total bacteria and on Bifidobacterium species balance in human colonic microbiota. Eighteen healthy volunteers (19 to 36 years old) were given a 875/125 mg dose of AMC twice a day for 5 days. Fecal samples were obtained before and after antibiotic exposure. After total DNA extraction, total bacteria and bifidobacteria were specifically quantified using real-time PCR. Dominant species were monitored over time using bacterial and bifidobacterial Temporal Temperature Gradient gel Electrophoresis (TTGE). At the end of AMC exposure, total bacterial concentrations as well as bifidobacteria concentrations were significantly reduced compared to before AMC exposure:10.7±0.1 log10 16S rRNA gene copies/g vs 11.1±0.1 log10 (p = 0.003) and 8.1±0.5 log10 16S rRNA gene copies/g vs 9.4±0.3 log10 (p = 0.003), respectively. At the same time, the mean similarity percentages of TTGE bacteria and TTGE bifidobacteria profiles were significantly reduced compared to before AMC exposure: 51.6%±3.5% vs 81.4%±2.1% and 55.8%±7.6% vs 84.5%±4.1%, respectively. Occurrence of B. adolescentis, B. bifidum and B. pseudocatenulatum/B. catenulatum species significantly decreased. Occurrence of B. longum remained stable. Moreover, the number of distinct Bifidobacterium species per sample significantly decreased (1.5±0.3 vs 2.3±0.3; p = 0.01). Two months after AMC exposure, the mean similarity percentage of TTGE profiles was 55.6% for bacteria and 62.3% for bifidobacteria. These results clearly demonstrated that a common antibiotic treatment may qualitatively alter the colonic microbiota. Such modifications may have potential long-term physiological consequences.  相似文献   

17.

Background

The prevalence of obesity is rising. Obesity can lead to cardiovascular and ventilatory complications through multiple mechanisms. Cardiac and pulmonary function in asymptomatic subjects and the effect of structured dietary programs on cardiac and pulmonary function is unclear.

Objective

To determine lung and cardiac function in asymptomatic obese adults and to evaluate whether weight loss positively affects functional parameters.

Methods

We prospectively evaluated bodyplethysmographic and echocardiographic data in asymptomatic subjects undergoing a structured one-year weight reduction program.

Results

74 subjects (32 male, 42 female; mean age 42±12 years) with an average BMI 42.5±7.9, body weight 123.7±24.9 kg were enrolled. Body weight correlated negatively with vital capacity (R = −0.42, p<0.001), FEV1 (R = −0.497, p<0.001) and positively with P 0.1 (R = 0.32, p = 0.02) and myocardial mass (R = 0.419, p = 0.002). After 4 months the study subjects had significantly reduced their body weight (−26.0±11.8 kg) and BMI (−8.9±3.8) associated with a significant improvement of lung function (absolute changes: vital capacity +5.5±7.5% pred., p<0.001; FEV1+9.8±8.3% pred., p<0.001, ITGV+16.4±16.0% pred., p<0.001, SR tot −17.4±41.5% pred., p<0.01). Moreover, P0.1/Pimax decreased to 47.7% (p<0.01) indicating a decreased respiratory load. The change of FEV1 correlated significantly with the change of body weight (R = −0.31, p = 0.03). Echocardiography demonstrated reduced myocardial wall thickness (−0.08±0.2 cm, p = 0.02) and improved left ventricular myocardial performance index (−0.16±0.35, p = 0.02). Mitral annular plane systolic excursion (+0.14, p = 0.03) and pulmonary outflow acceleration time (AT +26.65±41.3 ms, p = 0.001) increased.

Conclusion

Even in asymptomatic individuals obesity is associated with abnormalities in pulmonary and cardiac function and increased myocardial mass. All the abnormalities can be reversed by a weight reduction program.  相似文献   

18.
Central hypovolemia elevates hemostatic activity which is essential for preventing exsanguination after trauma, but platelet activation to central hypovolemia has not been described. We hypothesized that central hypovolemia induced by lower body negative pressure (LBNP) activates platelets. Eight healthy subjects were exposed to progressive central hypovolemia by LBNP until presyncope. At baseline and 5 min after presyncope, hemostatic activity of venous blood was evaluated by flow cytometry, thrombelastography, and plasma markers of coagulation and fibrinolysis. Cell counts were also determined. Flow cytometry revealed that LBNP increased mean fluorescence intensity of PAC-1 by 1959±455 units (P<0.001) and percent of fluorescence-positive platelets by 27±18%-points (P = 0.013). Thrombelastography demonstrated that coagulation was accelerated (R-time decreased by 0.8±0.4 min (P = 0.001)) and that clot lysis increased (LY60 by 6.0±5.8%-points (P = 0.034)). Plasma coagulation factor VIII and von Willebrand factor ristocetin cofactor activity increased (P = 0.011 and P = 0.024, respectively), demonstrating increased coagulation activity, while von Willebrand factor antigen was unchanged. Plasma protein C activity and tissue-type plasminogen activator increased (P = 0.007 and P = 0.017, respectively), and D-dimer increased by 0.03±0.02 mg l−1 (P = 0.031), demonstrating increased fibrinolytic activity. Plasma prothrombin time and activated partial thromboplastin time were unchanged. Platelet count increased by 15±13% (P = 0.014) and red blood cells by 9±4% (P = 0.002). In humans, LBNP-induced presyncope activates platelets, as evidenced by increased exposure of active glycoprotein IIb/IIIa, accelerates coagulation. LBNP activates fibrinolysis, similar to hemorrhage, but does not alter coagulation screening tests, such as prothrombin time and activated partial thromboplastin time. LBNP results in increased platelet counts, but also in hemoconcentration.  相似文献   

19.

Objective

To evaluate the effects of study participation per se at the beginning of a sleep extension trial between screening, randomization, and the run-in visit.

Design

Subjects were screened, returned for randomization (Comparison vs. Intervention) after 81 days (median), and attended run-in visit 121 days later.

Setting

Outpatient.

Patients

Obese (N = 125; M/F, 30/95; Blacks/Whites/Other, N = 73/44/8), mean weight 107.6±19.7 kg, <6.5 h sleep/night.

Intervention

Non-pharmacological sleep extension.

Measurements

Sleep duration (diaries and actigraphy watch), sleep quality (Pittsburgh Sleep Quality Index), daily sleepiness (Epworth Sleepiness Scale), fasting glucose, insulin and lipids.

Results

Prior to any intervention, marked improvements occurred between screening and randomization. Sleep duration increased (diaries: 357.4 ±51.2 vs. 388.1±48.6 min/night; mean±SD; P<0.001 screening vs. randomization; actigraphy: 344.3 ±41.9 vs. 358.6±48.2 min/night; P<0.001) sleep quality improved (9.1±3.2 vs. 8.2±3.0 PSQI score; P<0.001), sleepiness tended to improve (8.9±4.6 vs. 8.3±4.5 ESS score; P = 0.06), insulin resistance decreased (0.327±0.038 vs. 0.351±0.045; Quicki index; P<0.001), and lipids improved, except for HDL-C. Abnormal fasting glucose (25% vs. 11%; P = 0.007), and metabolic syndrome (42% vs. 29%; P = 0.007) both decreased. In absence of intervention, the earlier metabolic improvements disappeared at the run-in visit.

Limitations

Relatively small sample size.

Conclusions

Improvements in biochemical and behavioral parameters between screening and randomization changed the “true” study baseline, thereby potentially affecting outcome. While regression to the mean and placebo effect were considered, these findings are most consistent with the “Hawthorne effect”, according to which behavior measured in the setting of an experimental study changes in response to the attention received from study investigators. This is the first time that biochemical changes were documented with respect to the Hawthorne effect. The findings have implications for the design and conduct of clinical research.

Trial Registration

ClinicalTrials.gov NCT00261898.  相似文献   

20.

Background

Little is known about genetic basis and proteomics in valvular heart disease (VHD) including rheumatic (RVD) and degenerative (DVD) valvular disease. The present proteomic study examined the hypothesis that certain proteins may be associated with the pathological changes in the plasma of VHD patients.

Methods and Results

Differential protein analysis in the plasma identified 18 differentially expressed protein spots and 14 corresponding proteins or polypeptides by two-dimensional electrophoresis and mass spectrometry in 120 subjects. Two up-regulated (complement C4A and carbonic anhydrase 1) and three down-regulated proteins (serotransferrin, alpha-1-antichymotrypsin, and vitronectin) were validated by ELISA in enlarging samples. The plasma levels (n = 40 for each) of complement C4A in RVD (715.8±35.6 vs. 594.7±28.2 ng/ml, P = 0.009) and carbonic anhydrase 1 (237.70±15.7 vs. 184.7±10.8 U/L, P = 0.007) in DVD patients were significantly higher and that of serotransferrin (2.36±0.20 vs. 2.93±0.16 mg/ml, P = 0.025) and alpha-1-antichymotrypsin (370.0±13.7 vs. 413.0±11.6 µg/ml, P = 0.019) in RVD patients were significantly lower than those in controls. The plasma vitronectin level in both RVD (281.3±11.0 vs. 323.2±10.0 µg/ml, P = 0.006) and DVD (283.6±11.4 vs. 323.2±10.0 µg/ml, P = 0.011) was significantly lower than those in normal controls.

Conclusions

We have for the first time identified alterations of 14 differential proteins or polypeptides in the plasma of patients with various VHD. The elevation of plasma complement C4A in RVD and carbonic anhydrase 1 in DVD and the decrease of serotransferrin and alpha-1-antichymotrypsin in RVD patients may be useful biomarkers for these valvular diseases. The decreased plasma level of vitronectin – a protein related to the formation of valvular structure – in both RVD and DVD patients might indicate the possible genetic deficiency in these patients.  相似文献   

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