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71.
72.
This case report assessed quality of life, activities of daily living, motor symptoms, functional ability, neuromuscular parameters and mRNA expression of selected genes related to muscle protein synthesis and degradation in a patient with Multiple System Atrophy (MSA). The patient underwent resistance training with instability devices (i.e., bosu, dyna disk, balance disk, Swiss ball) for six months twice a week. After the six months training, the patient’s left and right quadriceps muscle cross-sectional area and leg press one-repetition maximum increased 6.4%, 6.8%, and 40%, respectively; the patient’s timed up and go, sit to stand, dynamic balance, and activities of daily living improved 33.3%, 28.6%, 42.3%, and 40.1%, respectively; the patient’s severity of motor symptoms and risk of falls decreased 32% and 128.1%, respectively. Most of the subscales of quality of life demonstrated improvements as well, varying from 13.0% to 100.0%. mRNA expression of mechanogrowth factor and mammalian target of rapamycin increased 12.7-fold and 1.5-fold, respectively. This case report describes likely the first nonpharmacological therapeutic tool that might be able to decrease the severity of motor symptoms and risk of falls, and to improve functional ability, neuromuscular parameters, and quality of the life in a patient with MSA.

Key points

  • Six months of resistance training with instability alleviate the MSA-related effects and improve the quality of life in a patient with MSA.
  • High complexity exercise intervention (i.e., resistance training with instability) may be very beneficial to individuals with impaired motor control and function as MSA patients.
  • Caution should be exercised when interpreting our findings as they cannot be generalized to the entire MSA population and they do not allow establishing causal conclusions on the effects of this mode of exercise on MSA.
Key words: Exercise training, risk of falls, motor symptoms, cross-sectional area  相似文献   
73.
74.
Dengue virus (DENV) is a flavivirus associated with clinical manifestations ranging in severity from self-limiting dengue fever, to the potentially life threatening condition, severe dengue. There are currently no approved antiviral therapies for the treatment of DENV. Here, we evaluated the antiviral potential of four broad-spectrum antivirals, UV-4B, interferon-alpha (IFN), sofosbuvir (SOF), and favipiravir (FAV) against DENV serotype 2 as mono- and combination therapy in cell lines that are physiologically relevant to human infection. Cell lines derived from human liver (HUH-7), neurons (SK-N-MC), and skin (HFF-1) were infected with DENV and treated with UV-4B, IFN, SOF, or FAV. Viral supernatant was sampled daily and infectious viral burden was quantified by plaque assay on Vero cells. Drug effect on cell proliferation in uninfected and infected cells was also assessed. UV-4B inhibited DENV in HUH-7, SK-N-MC, and HFF-1 cells yielding EC50 values of 23.75, 49.44, and 37.38 µM, respectively. Clinically achievable IFN concentrations substantially reduced viral burden in HUH-7 (EC50 = 102.7 IU/mL), SK-N-MC (EC50 = 86.59 IU/mL), and HFF-1 (EC50 = 163.1 IU/mL) cells. SOF potently inhibited DENV in HUH-7 cells but failed to produce the same effect in SK-N-MC and HFF-1 cells. Finally, FAV provided minimal suppression in HUH-7 and SK-N-MC cells, but was ineffective in HFF-1 cells. The two most potent anti-DENV agents, UV-4B and IFN, were also assessed in combination. UV-4B + IFN treatment enhanced antiviral activity in HUH-7, SK-N-MC, and HFF-1 cells relative to monotherapy. Our results demonstrate the antiviral potential of UV-4B and IFN against DENV in multiple physiologically relevant cell types.  相似文献   
75.
Molecular aspects of hepatic carcinogenesis   总被引:9,自引:0,他引:9  
Exogenous agents correlated with hepatocellular carcinoma (HCC) have been identified and well characterized. These agents, including the different viruses that cause chronic hepatitis and cirrhosis, can lead to regenerative nodules and dysplastic nodules/adenomatous hyperplasia. These conditions associated with several molecular alterations of hepatocyte ultimately culminate in hepatocellular carcinoma. Recently, there has been a great progress in the identification of somatic and germinative mutations that may be correlated with the development of HCC, justifying a review on the subject. Hence, the factors involved in the process of hepatic carcinogenesis, such as infection by the hepatitis B and C viruses, with a special focus in the molecular alterations described in recent years are discussed herein, pointing out areas potentially relevant for clinical development.  相似文献   
76.
We have obtained evidence that receptor-stimulated adenylate cyclase activity [ATP pyrophosphate-lyase (cyclizing), EC 4.6.1.1] is regulated physiologically in both embryonic and mature neurons. In a series of experiments using cultured retina cells from chicken embryos, we found that dopamine-sensitive adenylate cyclase activity spontaneously desensitized as cultures differentiated. The cellular response to dopamine reached a maximum after 5 days in culture and then decreased to 40% during the next 5 days. This spontaneous desensitization appeared to be caused by functional dopaminergic transmission because it could be blocked by the dopamine antagonist haloperidol. The ability of added dopamine at 100 microM to cause near-complete desensitization is consistent with this conclusion. Pharmacologically induced desensitization required 31 hr for maximal effect and was half-maximal at 1-10 microM dopamine. Analogous desensitization of the adenosine-dependent adenylate cyclase system also was noted. When dopamine was removed from the medium of chronically treated cultures, cells resensitized to subsequent stimulation at a very slow rate. Resensitization likely depended on replacement of dopamine receptors because chronic dopamine treatment caused the disappearance of binding sites for the ligand [3H]spiroperidol. In a second series of experiments, using hatched animals, we found that similar regulation of dopamine receptor binding sites and activity could be elicited by manipulation of environmental light, a treatment thought to influence dopaminergic transmission. Retinas from animals in constant light had less specific [3H]spiroperidol binding (35 fmol/mg of protein) than did retinas from animals in constant darkness (66 fmol/mg of protein) and made less cAMP in response to added dopamine. Our results indicate that regulation of the dopamine receptor system begins early in development and continues to function in mature synapses.  相似文献   
77.
To understand the hematopoietic and nonhematopoietic responses to interleukin-3 (IL-3), expression of cell-surface IL-3 receptors (IL-3R) was examined on bone marrow (BM) cells and peripheral blood (PB) cells of rhesus monkeys during the course of in vivo IL-3 treatment. Whereas IL-3R expression is low in untreated monkeys, IL-3 administration led to a gradual increase in both low- and high-affinity binding sites for IL-3. This increase reflected the total number of cells expressing IL- 3Rs, as detected by flow cytometry using biotinylated IL-3. Most of these IL-3R+ cells in both BM and PB could be characterized as basophilic granulocytes that contained high levels of histamine. In contrast to the effect on these differentiated cells, IL-3 administration did not significantly alter the low level IL-3R expression on immature, CD34+ cells. Further flow cytometric analysis using biotinylated growth factors showed that the IL-3R+ basophils also expressed receptors for granulocyte-macrophage colony-stimulating factor (GM-CSF), but not for IL-6 or Kit ligand. These findings indicated that the IL-3R+ cells included neither monocytes, which express GM-CSFRs and IL-6Rs abundantly, nor mast cells, which express c- kit. By combining flow cytometric and Scatchard data, it was calculated that the basophils contain as many as 1 to 2 x 10(3) high-affinity IL- 3Rs and 15 to 30 x 10(3) low-affinity sites. The finding that in vivo IL-3 treatment leads to the production of large numbers of cells that express high levels of IL-3R and are capable of producing histamine provides an explanation for the often severe allergic reactions that occur during prolonged IL-3 administration. It also indicates that IL- 3, in addition to its direct effects on hematopoietic cells, may also stimulate hematopoiesis through the release of secondary mediators such as histamine by IL-3-responsive mature cells.  相似文献   
78.
Capnocytophaga infection involving a portal-systemic vascular shunt   总被引:1,自引:0,他引:1  
Capnocytophaga sp., a microaerophilic gram-negative isolate of the human oral cavity, has previously been reported to cause sinusitis, empyema, wound infections, conjunctivitis, subphrenic abscess, osteomyelitis, bacteremia, cervical abscess, and endocarditis. We report the unusual case of infection with this organism at the anastamotic site of a splenorenal portosystemic vascular shunt. In this case, the pathogenesis is presumed to be bacteremia related to mucosal trauma from endoscopic injection sclerotherapy or bacteremia secondary to dental infection. The characteristics and antibiotic sensitivities of Capnocytophaga are reviewed.  相似文献   
79.
After laryngectomy for treatment of cancer of the larynx, the patient may have vocal rehabilitation by esophageal speech. Some patients fail to achieve the esophageal speech due to reasons involving surgery, radiotherapy, and psychological alterations. Our hypothesis is that the esophageal motility alterations consequent to laryngectomy may be involved in the failure to achieve esophageal speech. Using manometry with continuous perfusion, we studied the esophageal motility of 25 laryngectomized patients, 10 of them able to produce esophageal speech and 15 unable to produce esophageal speech, and 40 asymptomatic normal volunteers. The lower esophageal sphincter (LES) pressure was measured by the rapid pull-through method and the upper esophageal sphincter (UES) pressure by the station pull-through method. The contractions were measured at 5, 10, and 15 cm above the LES after the subjects performed 10 swallows with a 5-mL bolus of water. By comparing volunteers and laryngectomized patients, we found a lower UES pressure, lower amplitude of contractions, and increased percentage of simultaneous contractions in laryngectomized patients (p <0.05). There was no difference between patients able and unable to produce esophageal speech in LES and UES pressure, esophageal contraction duration and velocity, or in the percentage of failed and simultaneous contractions. The esophageal contraction amplitude was lower in patients who acquired esophageal speech than in patients who did not (p <0.05 at 10 cm from LES). We conclude that there are esophageal motility alterations in laryngectomized patients but only the decrease of esophageal contraction amplitude seems to be associated with the acquisition of esophageal speech.  相似文献   
80.
Energy landscapes have been used to conceptually describe and model protein folding but have been difficult to measure experimentally, in large part because of the myriad of partly folded protein conformations that cannot be isolated and thermodynamically characterized. Here we experimentally determine a detailed energy landscape for protein folding. We generated a series of overlapping constructs containing subsets of the seven ankyrin repeats of the Drosophila Notch receptor, a protein domain whose linear arrangement of modular structural units can be fragmented without disrupting structure. To a good approximation, stabilities of each construct can be described as a sum of energy terms associated with each repeat. The magnitude of each energy term indicates that each repeat is intrinsically unstable but is strongly stabilized by interactions with its nearest neighbors. These linear energy terms define an equilibrium free energy landscape, which shows an early free energy barrier and suggests preferred low-energy routes for folding.  相似文献   
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