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31.

Objective

To establish a miRNA signature for metastasis in an animal model of esophageal adenocarcinoma (EAC).

Background

The incidence of esophageal adenocarcinoma (EAC) has dramatically increased and esophageal cancer is now the sixth leading cause of cancer deaths worldwide. Mortality rates remain high among patients with advanced stage disease and esophagectomy is associated with high complication rates. Hence, early identification of potentially metastatic disease would better guide treatment strategies.

Methods

The modified Levrat’s surgery was performed to induce EAC in Sprague-Dawley rats. Primary EAC and distant metastatic sites were confirmed via histology and immunofluorescence. miRNA profiling was performed on primary tumors with or without metastasis. A unique subset of miRNAs expressed in primary tumors and metastases was identified with Ingenuity Pathway Analysis (IPA) along with upstream and downstream targets. miRNA-linked gene expression analysis was performed on a secondary cohort of metastasis positive (n=5) and metastasis negative (n=28) primary tumors.

Results

The epithelial origin of distant metastasis was established by IF using villin (VIL1) and mucin 5AC (MUC5AC) antibodies. miRNome analysis identified four down-regulated miRNAs in metastasis positive primary tumors compared to metastasis negative tumors: miR-92a-3p (p=0.0001), miR-141-3p (p=0.0022), miR-451-1a (p=0.0181) and miR133a-3p (p=0.0304). Six target genes identified in the top scoring networks by IPA were validated as significantly, differentially expressed in metastasis positive primary tumors: Ago2, Akt1, Kras, Bcl2L11, CDKN1B and Zeb2.

Conclusion

In vivo metastasis was confirmed in the modified Levrat’s model. Analysis of the primary tumor identified a distinctive miRNA signature for primary tumors that metastasized.  相似文献   
32.
The aim was to develop niosomal gel as a transdermal nanocarrier for improved systemic availability of lopinavir. Niosomes were prepared using thin-film hydration method and optimized for molar quantities of Span 40 and cholesterol to impart desirable characteristics. Comparative evaluation with ethosomes was performed using ex vivo skin permeation, fluorescence microscopy, and histopathology studies. Clinical utility via transdermal route was acknowledged using in vivo bioavailability study in male Wistar rats. The niosomal formulation containing lopinavir, Span 40, and cholesterol in a molar ratio of 1:0.9:0.6 possessed optimally high percentage of drug entrapment with minimum mean vesicular diameter. Ex vivo skin permeation studies of lopinavir as well as fluorescent probe coumarin revealed a better deposition of ethosomal carriers but a better release with niosomal carriers. Histopathological studies indicated the better safety profile of niosomes over ethosomes. In vivo bioavailability study in male Wistar rats showed a significantly higher extent of absorption (AUC0→∞, 72.87 h × μg/ml) of lopinavir via transdermally applied niosomal gel as compared with its oral suspension. Taken together, these findings suggested that niosomal gel holds a great potential of being utilized as novel, nanosized drug delivery vehicle for transdermal lopinavir delivery.KEY WORDS: ethosomes, lopinavir, niosomes, transdermal  相似文献   
33.

Background

A weakened sense of self may contribute to psychotic experiences. Body ownership, one component of self-awareness, can be studied with the rubber hand illusion (RHI). Watching a rubber hand being stroked while one''s unseen hand is stroked synchronously can lead to a sense of ownership over the rubber hand, a shift in perceived position of the real hand, and a limb-specific drop in stimulated hand temperature. We aimed to assess the RHI in schizophrenia using quantifiable measures: proprioceptive drift and stimulation-dependent changes in hand temperature.

Methods

The RHI was elicited in 24 schizophrenia patients and 21 matched controls by placing their unseen hand adjacent to a visible rubber hand and brushing real and rubber hands synchronously or asynchronously. Perceived finger location was measured before and after stimulation. Hand temperature was taken before and during stimulation. Subjective strength of the illusion was assessed by a questionnaire.

Results

Across groups, the RHI was stronger during synchronous stimulation, indicated by self-report and proprioceptive drift. Patients reported a stronger RHI than controls. Self-reported strength of RHI was associated with schizotypy in controls Proprioceptive drift was larger in patients, but only following synchronous stimulation. Further, we observed stimulation-dependent changes in skin temperature. During right hand stimulation, temperature dropped in the stimulated hand and rose in the unstimulated hand. Interestingly, induction of RHI led to an out-of-body experience in one patient, linking body disownership and psychotic experiences.

Conclusions

The RHI is quantitatively and qualitatively stronger in schizophrenia. These findings suggest that patients have a more flexible body representation and weakened sense of self, and potentially indicate abnormalities in temporo-parietal networks implicated in body ownership. Further, results suggest that these body ownership disturbances might be at the heart of a subset of the pathognomonic delusions of passivity.  相似文献   
34.
In order to survey the behaviour of choosing the alley area instead of a cubicle as a lying place (cubicle refusal), a questionnaire was sent to the 273 dairy farms in Norway known to keep cows in cubicle housing systems. Sixty-six percent of the farmers contacted were included in the study. The median herd size was 18 cows (range 7–118). More than 85% of the herds had sheds providing one or more cubicles per cow. The mean herd occurrence of cubicle refusal was 6%, but showed great variation (range 0–55%). Regression analysis showed a significant association between rearing heifers in slatted floor pens and an increased cubicle refusal occurrence (p = 0.02, R2 = 0.05), while herd size, use of litter, or cubicle-to-animal ratio were not found to be associated with cubicle refusal. The practice of rearing heifers in slatted floor pens accounted for about one half of the observed cubicle refusal (etiologic fraction = 0.51).  相似文献   
35.
There is a pronounced decline in sleep with age. Diminished output from the circadian oscillator, the suprachiasmatic nucleus, might play a role, because there is a decrease in the amplitude of the day-night sleep rhythm in the elderly. However, sleep is also regulated by homeostatic mechanisms that build sleep drive during wakefulness, and a decline in these mechanisms could also decrease sleep. Because this question has never been addressed in old animals, the present study examined the effects of 12 h wakefulness on compensatory sleep response in young (3.5 mo) and old (21.5 mo) Sprague-Dawley and F344 rats. Old rats in both strains had a diminished compensatory increase in slow-wave sleep (SWS) after 12 h of wakefulness (0700-1900, light-on period) compared with the young rats. In contrast, compensatory REM sleep rebound was unaffected by age. To assess whether the reduced SWS rebound in old rats might result from loss of neurons implicated in sleep generation, we counted the number of c-Fos immunoreactive (c-Fos-ir) cells in the ventral lateral preoptic (VLPO) area and found no differences between young and old rats. These findings indicate that old rats, similar to elderly humans, demonstrate less sleep after prolonged wakefulness. The findings also indicate that although old rats have a decline in sleep, this cannot be attributed to loss of VLPO neurons implicated in sleep.  相似文献   
36.
The present study investigates the preparation of celecoxib-loaded albumin microspheres and the biodistribution of technetium-99m (99mTc)-labeled celecoxib as well as its microspheres after intravenous administration. Microspheres were prepared using a natural polymer BSA using emulsification chemical cross-linking method. The prepared microspheres were characterized for entrapment efficiency, particle size, and in vitro drug release. Surface morphology was studied by scanning electron microscopy. Biodistribution studies were performed by radiolabeling celecoxib (CS) and its microspheres (CMS) using99mTc and injecting arthritic rats intravenously. The geometric mean diameter of the microspheres was found to be 5.46 μm. In vitro release studies indicated that the microspheres sustained the release of the drug for }6 days. Radioactivity measured in different organs after intravenous administration of celecoxib solution showed a significant amount of radioactivity in the liver and spleen. In case of celecoxib-loaded microspheres, a significant amount of radioactivity accumulated in the lungs. No significant difference (P>.1) in the radioactivity was observed between the inflamed joint and the noninflamed joint following intravenous injection of99mTc-CS. However, in case of the microspheres (CMS), the radioactivity present in the inflamed joint was 2.5-fold higher than in the noninflamed joint. The blood kinetic studies revealed that celecoxib-loaded albumin microspheres exhibited prolonged circulation than the celecoxib solution.  相似文献   
37.
Fifty-nine of the 65 dairy farms with cubicle sheds in the Norwegian county of Oppland in 1990 were included in a study of rearing accommodation, cubicle refusal and mastitis incidence. The farmers recorded the favoured resting location of the individual cows and heifers throughout the final week of pregnancy as well as during calving. The observations were matched with individual records of mastitis cases during the first 30 days after calving. Mastitis incidence in the heifers was analysed by logistic regression using rearing accommodation and cubicle refusal as independent variables, controlling for herd as a clustering factor. Cubicle refusal was found in 29% of the heifers, but in only 3% of older cows. The results of the analysis indicated a tendency for cubicle refusal to be associated with an increased mastitis incidence among the heifers (OR = 2.2, c.i.95%OR = 0.9–5.4, P = 0.08). Cubicle refusal accounted for 21% (0–32%) of the mastitis cases in the study population (PAF = 0.21).  相似文献   
38.

Background

We report a case of pulmonary sarcoma which is a rare cause of the common symptom of dyspnea.

Case presentation

A fifty-one year old previously healthy male presented to the emergency room with complaints of dyspnea on exertion. A cardiac workup including an exercise stress test was negative but an echocardiography showed pulmonary stenosis. Cardiac MRI showed a large mass extending from the pulmonic valve to both the right and left pulmonary arteries suggestive of sarcoma. A complete resection and repair of the pulmonary artery was done and adjuvant chemotherapy with doxorubicin and ifosfamide was recommended. The patient is currently disease free after eighteen months.

Conclusion

Pulmonary artery sarcomas are a difficult diagnosis. The diagnosis may remain elusive for some time until the proper imaging techniques are utilized to make a diagnosis. Earlier and accurate diagnosis may lead to earlier interventions and improve survival.
  相似文献   
39.
IntroductionThere is evidence that early screening for pulmonary arterial hypertension (PAH) in systemic sclerosis (SSc) improves outcomes. We compared the predictive accuracy of two recently published screening algorithms (DETECT 2013 and Australian Scleroderma Interest Group (ASIG) 2012) for SSc-associated PAH (SSc-PAH) with the commonly used European Society of Cardiology/European Respiratory Society (ESC/ERS 2009) guidelines.MethodsWe included 73 consecutive SSc patients with suspected PAH undergoing right heart catheterization (RHC). The three screening models were applied to each patient. For each model, contingency table analysis was used to determine sensitivity, specificity, and positive (PPV) and negative (NPV) predictive values for PAH. These properties were also evaluated in an ‘alternate scenario analysis’ in which the prevalence of PAH was set at 10%.ResultsRHC revealed PAH in 27 (36.9%) patients. DETECT and ASIG algorithms performed equally in predicting PAH with sensitivity and NPV of 100%. The ESC/ERS guidelines had sensitivity of 96.3% and NPV of only 91%, missing one case of PAH; these guidelines could not be applied to three patients who had absent tricuspid regurgitant (TR) jet. The ASIG algorithm had the highest specificity (54.5%). With PAH prevalence set at 10%, the NPV of the models was unchanged, but the PPV dropped to less than 20%.ConclusionsIn this cohort, the DETECT and ASIG algorithms out-perform the ESC/ERS guidelines, detecting all patients with PAH. The ESC/ERS guidelines have limitations in the absence of a TR jet. Ultimately, the choice of SSc-PAH screening algorithm will also depend on cost and ease of application.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-015-0517-5) contains supplementary material, which is available to authorized users.  相似文献   
40.
The objective of the present investigation was to reduce the bitterness with improved dissolution, in acidic medium (pH 1.2), of mefloquine hydrochloride (MFL). Microparticles were prepared by coacervation method using Eudragit E (EE) as polymer and sodium hydroxide as precipitant. A 32 full factorial design was used for optimization wherein the drug concentration (A) and polymer concentration (B) were selected as independent variables and the bitterness score, particle size and dissolution at various pH were selected as the dependent variables. The desirability function approach has been employed in order to find the best compromise between the different experimental responses. The model is further cross validated for bias. The optimized microparticles were characterized by FT-IR, DSC, XRPD and SEM. Bitterness score was evaluated by human gustatory sensation test. Multiple linear regression analysis revealed that the reduced bitterness of MFL can be obtained by controlling the dissolution of microparticles at pH 6.8 and increasing the EE concentration. The increase in polymer concentration leads to reduction in dissolution of microparticles at pH > 5 due to its insolubility. However the dissolution studies at pH 1.2 demonstrated enhanced dissolution of MFL from microparticles might be due to the high porosity of the microparticles, hydrophilic nature of the EE, and improved wettability, provided by the dissolved EE. The bitterness score of microparticles was decreased to zero compared to 3+ of pure ARM. In conclusion the bitterness of MFL was reduced with improved dissolution at acidic pH.  相似文献   
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