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991.

Purpose  

Whole lung lavage (WLL) pathophysiologically represents a human model of controlled lung de-aeration, resembling various pathological conditions encountered in the critically ill. Through one-lung ventilation and progressive alveolar flooding, it mimics, respectively, re-absorption atelectasis formation and lung consolidation. With re-ventilation of the treated lung, PEEP application and diuretics administration, it then creates a model of pulmonary edema and its progressive resolution. No studies have so far described lung aeration changes during WLL with ultrasound: objectives of the study were to describe ultrasound findings during WLL with validated semiotics in the critically ill and to investigate their relation with the lung’s state of relative aeration.  相似文献   
992.
The effects of a very prolonged treatment with octreotide (OC)-long-acting repeatable (LAR) were retrospectively evaluated in 110 patients with acromegaly, showing a GH/IGF-I decrease of at least 20% vs. baseline after a short-term (6-month) OC-LAR challenge. OC-LAR was given (20 mg, im, every 28 d for 3 injections, then individually tailored) as adjuvant treatment (AT) in 59. The other 51 [primary treatment (PT)] were naive or previously treated by pharmacotherapy. IGF-I normalized in 83 patients [75%; from 770 +/- 26 (mean +/- SE) to 276 +/- 15 micro g/liter; P < 0.0001; median follow-up, 30 months; range, 18-54 months). A progressive increase in the rate of IGF-I normalization was observed. GH fell to less than 2.5 micro g/liter in 72% and to less than 1 micro g/liter in 27% (from 20.7 +/- 2.4 to 2.2 +/- 0.2 micro g/liter; P < 0.0001). PT and AT patients achieved similar final GH/IGF-I levels and rates of normalization. Patients attaining safe GH and normal IGF-I had GH levels below 5 micro g/liter after 3 months and IGF-I levels below 550 micro g/liter after 6 months. No tachyphylaxis was observed. The up-titration to 30 mg improved IGF-I suppression. Elderly patients had greater sensitivity. Tumor shrank in 46% of assessable patients, in 77% of PT patients, and in 91% of naive patients. The powerful suppression of GH/IGF-I levels without tachyphylaxis, the finding of progressive increase in the rate of IGF-I normalization and of superimposable effects in PT and AT patients, and the predictive value of short-term results support the role of PT of acromegaly with OC-LAR in at least some patients.  相似文献   
993.
994.
Objectives.— We investigated (1) a possible relationship between the functional activity of the endocannabinoid system and the facilitation of pain processing in migraineurs with medication‐overuse headache, and (2) the effect of withdrawal treatment on both. Background.— The endocannabinoid system antinociception effect includes prevention of nociceptive pathways sensitization. The sensitization of the pain pathways has been demonstrated to be pivotal in the development and maintenance of chronic form of migraine, including medication‐overuse headache. Methods.— We used the temporal summation threshold of the nociceptive withdrawal reflex to explore the spinal cord pain processing, and the platelet activity of the enzyme fatty acid amide hydrolase to detect the functional state of the endocannabinoid system in 27 medication‐overuse headache subjects before and 10 and 60 days after a standard withdrawal treatment and compared results with those of 14 controls. Results.— A significantly reduced temporal summation threshold and increased related pain sensation was found in subjects before withdrawal treatment when compared with controls. A significant fatty acid amide hydrolase activity reduction coupled with a significant improvement (reduction) in facilitation of spinal cord pain processing (increase in temporal summation threshold and reduction in related pain sensation) was found in medication‐overuse headache subjects at both 10 and 60 days after withdrawal treatment when compared with medication‐overuse headache subjects before withdrawal treatment. Conclusions.— We demonstrated a marked facilitation in spinal cord pain processing in medication‐overuse headache before withdrawal treatment when compared with controls. Furthermore, the acute reduction of the fatty acid amide hydrolase activity coupled with a reduction of the facilitation in pain processing immediately (10 days) after withdrawal treatment and its persistence 60 days after withdrawal treatment could represent the consequence of a mechanism devoted to acutely reduce the degradation of endocannabinoids and aimed to increase the activity of the endocannabinoid system that results in an antinociceptive effect.  相似文献   
995.
996.
997.
Epinephrine and norepinephrine plasma levels were assessed in dogs in relation to paw preference following an immune challenge with rabies vaccine. The results showed that both catecholamines increased after the vaccine administration, confirming the main role of the sympathetic nervous system in the modulation activity between the brain and the immune system. Moreover, ambidextrous dogs showed a significantly higher increase of epinephrine levels 8 days after immunization with respect to right- and left-pawed dogs, suggesting that the biological activity of this molecule could be key for a different immune response with regard to laterality.  相似文献   
998.
Recent studies suggest that the oligomers of short amyloid beta (Aβ) peptides such as Aβ25–35 as well as full-length Aβ peptides (i.e. Aβ1–40 and Aβ1–42 peptides) are responsible for synaptic dysfunction and/or neuronal loss in Alzheimer's disease (AD). Among antioxidant phytochemicals derived from fruit and vegetables, cyanidin 3-O-glucoside (Cy-3G) has recently gained attention for its neuroprotective properties. In this in vitro study, we demonstrated that Cy-3G can inhibit Aβ25–35 spontaneous aggregation into oligomers and their neurotoxicity in human neuronal SH-SY5Y cells. In particular, the pre- and co-treatment of SH-SY5Y cells with Cy-3G reduced the neuronal death, in terms of apoptosis and necrosis, elicited by Aβ25–35 oligomers. Cy-3G also shows the interesting ability to prevent the early events leading to neuronal death such as the Aβ25–35 oligomer binding to plasma membrane and the subsequent membrane integrity loss. Taken together, these findings suggest that Cy-3G may be considered a phytochemical with neuroprotective properties useful in finding potential drug or food supplements for the therapy of AD.  相似文献   
999.
The HTLV-1 transactivator Tax is an oncoprotein capable of deregulating the expression of many cellular genes and interfering with signalling pathways. Here we show that Tax-1 is phosphorylated in vitro by the pleiotropic human serine/threonine kinase CK2 at three residues, Ser-336, Ser-344 and Thr-351, close to and within its C-terminal PDZ-binding motif. We also show that the mutation of Thr-351 to aspartate abolishes Tax-1 binding to the scaffold protein hDlg, a tumour suppressor factor, while having no effect on transactivation. These results suggest that CK2, whose constitutive activity is often hijacked by viruses to sustain their vital cycle, could modulate Tax-1 oncogenic interactions.  相似文献   
1000.
The genus Lactobacillus is a heterogeneous group of lactic acid bacteria (LAB) with important implications in food fermentation. The ability to colonize a variety of habitats is a direct consequence of the wide metabolic versatility of this group of LAB. Consequently, lactobacilli have been used for decades in food preservation, as starters for dairy products, fermented vegetables, fish and sausages as well as silage inoculants. Lactobacilli have also been proposed as probiotics and microbial cell factories for the production of nutraceuticals. However, a wide range of applications of lactobacilli in food biotechnology remains potential, whereas a number of important strains still need to be discovered and characterized. This article provides an overview of the taxonomy of lactobacilli and describes four of the most significant case studies on the application of this group of LAB in food and feed biotechnology, including their use as probiotics, dairy starters, silage inoculants, and microbial cell factories. The importance of access to and exchange of biological material within and between different strain collections as a crucial step in expanding the range of different biotechnological applications of lactobacilli is also emphasized.  相似文献   
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