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981.
982.
983.
Apathy is a common problem observed in numerous neurologic, psychiatric, and other medical conditions. It is independent from other symptoms and has been associated with a variety of negative outcomes. However, little empirical research has been conducted on potential psychologic or pharmacologic treatments for apathy. The impact of several different medications has been investigated, but very few reports have used well-controlled study designs. At present, agents that potentiate dopamine release and/or delay dopamine reuptake in the central nervous system appear promising for use in apathy. Among these, atypical antipsychotics and methylphenidate have received the greatest attention, and both have been demonstrated to reduce apathy in several patient populations. These findings appear consistent with evidence supporting a role for frontal-subcortical circuitry abnormality in the etiology of apathy. Another class of medication that has been the subject of a larger number of investigations is the acetylcholinesterase inhibitors. These have been reported to reduce apathy in patients with dementia and individuals with traumatic brain injury. Several psychologic interventions have been assessed, largely in geriatric populations, but most have been the subject of only one or a very small number of studies. With this caveat, interventions that have shown promise include participation in discussion groups and cognitive stimulation. Despite some promising findings, further large-scale, well-controlled clinical trials of potentially helpful pharmacologic and psychologic interventions for apathy are essential before any firm recommendations can be made. In the interim, careful evaluation of possible psychosocial and biological contributors to apathy in any given patient is suggested, with treatment planning based accordingly. 相似文献
984.
Schweizer R Martin DD Haase M Roth J Trebar B Binder G Schwarze CP Ranke MB 《BONE》2007,41(5):875-881
BACKGROUND AND AIMS: Treatment with GH in short children has focused on height development. Little is known about the concomitant changes in muscle mass, bone structure and bone strength. METHODS: Muscle area as well as parameters of bone architecture (bone mineral content, BMC; volumetric cortical density, total bone area, TBA; cortical area, cortical thickness, CT; and marrow area) were measured by means of pQCT (Stratec) at 65% of the proximal length of the forearm. The strength-strain index (SSI) was calculated as an indicator of bone strength. RESULTS: Prepubertal children with GHD (mean values: age; 7.2 years; height SDS=-2.9 SDS; GH dose: 30 microg/kg/d) were followed at 0, 6, 12 (n=74) and 24 (n=55) months. Prepubertal children with SGA (mean values: age: 7.1 years; height SDS=-3.4 SDS; GH dose: 55 mug/kg/d) were followed at 0, 6, 12 (n=47) and 24 (n=35) months. Both groups showed a similar increase in height. At GH start, muscle mass and bone characteristics were lower than normal but similar in SGA vs. GHD. Muscle area (mean values, SDS) increased from -3.0 to -1.5 in SGA and from -2.4 to -1.0 in GHD. Bone geometry changed in a biphasic mode, with an increase in total bone area and lowering of bone mineral content (BMC) during the first 12 months, followed by an increase of BMC and CT thereafter. SSI (mean values, mm(3)) improved from 78 to 114 in GHD and from 62 to 101 in SGA after 24 months on GH. The increment in terms of SDS did not reach significance in SGA. SSI correlated positively with muscle area before and during GH treatment. CONCLUSIONS: Bone strength and muscle mass are impaired in prepubertal children with GHD and SGA. Exogenous GH can indirectly improve bone structure and strength by inducing an increase in muscle mass. Our findings support the assumption that, in SGA, there is impaired tissue responsiveness to GH. 相似文献
985.
Kasibhatla S Baichwal V Cai SX Roth B Skvortsova I Skvortsov S Lukas P English NM Sirisoma N Drewe J Pervin A Tseng B Carlson RO Pleiman CM 《Cancer research》2007,67(12):5865-5871
A novel series of 4-arylaminoquinazolines were identified from a cell-based screening assay as potent apoptosis inducers. Through structure-activity relationship studies, MPC-6827 and its close structural analogue, MPI-0441138, were discovered as proapoptotic molecules and mitotic inhibitors with potencies at low nanomolar concentrations in multiple tumor cell lines. Photoaffinity and radiolabeled analogues of MPC-6827 were found to bind a 55-kDa protein, and this binding was competed by MPC-6827, paclitaxel, and colchicine, but not vinblastine. MPC-6827 effectively inhibited the polymerization of tubulin in vitro, competed with colchicine binding, and disrupted the formation of microtubules in a variety of tumor cell lines, which together showed the molecular target as tubulin. Treatment of MCF-7 breast carcinoma or Jurkat leukemia cells with MPC-6827 led to pronounced G2-M cell cycle arrest followed by apoptosis. Apoptosis, as determined by terminal deoxyribonucleotidyl transferase-mediated dUTP nick end labeling assay, was preceded by loss of mitochondrial membrane potential, cytochrome c translocation from mitochondria to nuclei, activation of caspase-3, and cleavage of poly(ADP-ribose) polymerase. MPC-6827 was equipotent in an in vitro growth inhibition assay in several cancer cell lines regardless of the expression levels of the multidrug resistance ABC transporters MDR-1 (Pgp-1), MRP-1, and BCRP-1. In B16-F1 allografts and in OVCAR-3, MIAPaCa-2, MCF-7, HT-29, MDA-MB-435, and MX-1 xenografts, statistically significant tumor growth inhibition was observed with MPC-6827. These studies show that MPC-6827 is a microtubule-disrupting agent with potent and broad-spectrum in vitro and in vivo cytotoxic activities and, therefore, MPC-6827 is a promising candidate for development as a novel therapeutic for multiple cancer types. 相似文献
986.
Ohtani S Iwamaru A Deng W Ueda K Wu G Jayachandran G Kondo S Atkinson EN Minna JD Roth JA Ji L 《Cancer research》2007,67(13):6293-6303
101F6 is a candidate tumor suppressor gene harbored on chromosome 3p21.3, a region with frequent and early allele loss and genetic alterations in many human cancers. We previously showed that enforced expression of wild-type 101F6 by adenoviral vector-mediated gene transfer significantly inhibited tumor cell growth in 3p21.3-deficient non-small cell lung cancer (NSCLC) cells in vitro and in vivo. The molecular mechanism of 101F6-mediated tumor suppression is largely unknown. A computer-aided structural and functional model predicts the 101F6 protein to be a member of the cytochrome b561 protein family that is involved in the regeneration of the antioxidant ascorbate. 101F6 protein is expressed in normal lung bronchial epithelial cells and fibroblasts but is lost in most lung cancers. Treatment with 101F6 nanoparticle-mediated gene transfer in combination with a subpharmacologic dose (200-500 micromol/L) of ascorbate synergistically and selectively inhibited lung cancer cell growth in vitro. Systemic injection of 101F6 nanoparticles plus the i.p. injection of ascorbate synergistically inhibited both tumor formation and growth in human NSCLC H322 orthotopic lung cancer mouse models (P<0.001). Furthermore, exogenous expression of 101F6 enhanced intracellular uptake of ascorbate, leading to an accumulation of cytotoxic H(2)O(2) and a synergistic killing of tumor cells through caspase-independent apoptotic and autophagic pathways. The antitumor synergism showed by the combination treatment with systemic administration of 101F6 nanoparticles and ascorbate on lung cancer offers an attractive therapeutic strategy for future clinical trials in cancer prevention and treatment. 相似文献
987.
J J Roth J J Sung M S Granick M P Solomon M T Longaker V L Rothman R F Nicosia G P Tuszynski 《Annals of plastic surgery》1999,42(5):553-563
Thrombospondin 1 (TSP-1), an adhesive glycoprotein, plays an important role in platelet adhesion, inflammation, cell-cell interaction, and angiogenesis. TSP-1 is expressed by endothelial cells, fibroblasts, and macrophages. The unique cysteine-serinevaline-threonine-cysteine-glycine (CSVTCG) binding domain of TSP-1 also plays an important role in cell binding and modulation of cellular processes. The purpose of this study was to evaluate histologically and quantitatively TSP-1 and its CSVTCG receptor in fetal skin wounds over time. Pregnant ewes underwent laparotomy and hysterotomy. At 65 days gestation (term, 145 days), incisional and excisional wounds were created on the fetal back in a similar position on each animal. The uterus and laparotomy were closed. The wounds were harvested on days 1, 3, 7, 21, and 28. Expression of TSP-1 and its CSVTCG receptor was evaluated immunohistochemically and quantitated by computer image analysis in units of absorbance. Immunoglobulin G (negative) controls were performed and subtracted from the TSP-1 sample to eliminate background absorbance readings. Serum (negative) control was used for the CSVTCG receptor. Platelet concentrates were used as the positive control: TSP-1, 63.43; CSVTCG, 58.72. Results are expressed as absorbance+/-SEM. Results of TSP-1 are as follows: day 1, 33.02+/-0.26; day 3, 22.21+/-0.14; day 7, 20.56+/-1.07; day 21, 7.76+/-0.40; and day 28, 5.99+/-0.03. TSP-1 displays an early peak during fetal skin repair, followed by a steep decrease over the viewed time period. Results of CSVTCG receptor are as follows: day 1, 26.19+/-2.43; day 3, 30.20+/-0.64; day 7, 24.56+/-0.80; day 21, 24.70+/-0.40; and day 28, 21.65+/-1.39. Thus, CSVTCG receptor displays a slowed decrease in expression over time during fetal repair. No significant differences were noted between incisional and excisional samples. Temporal and histological differences exist in the localization and expression of TSP-1 and its CSVTCG receptor during fetal wound repair. TSP-1 is upregulated in tissues early. This corresponds with the known role of TSP-1 in cell-cell interaction, including potentiation of growth factor activity. TSP-1 also modulates matrix, allowing scar-free provisional matrix in the earlier stages of repair deposited by platelets. The potentiation of cell-associated protease activity by TSP-1 can support tissue and matrix turnover. This activity of TSP-1 may contribute to the formation of a scarless wound. TSP-1 destabilizes extracellular matrix contacts, and facilitates mitosis and migration. The action of TSP-1 as an adhesive protein allows numerous different cells to adhere to the extracellular membrane. CSVTCG receptor expression decreases during fetal repair as the cells migrate to the epithelial surface, suggesting a significant role of the CSVTCG receptor in keratinocytic maturation, differentiation, and epithelization. 相似文献
988.
Phase II study of cisplatin and paclitaxel in advanced carcinoma of the urothelium: an Eastern Cooperative Oncology Group Study. 总被引:6,自引:0,他引:6
R Dreicer J Manola B J Roth M B Cohen A K Hatfield G Wilding 《Journal of clinical oncology》2000,18(5):1058-1061
PURPOSE: Cisplatin and paclitaxel are active agents in advanced urothelial cancer. A phase II trial of this combination was performed to determine the activity and toxicity of these agents in a multi-institutional setting. PATIENTS AND METHODS: Fifty-two patients with advanced urothelial carcinoma were treated on one day with paclitaxel 175 mg/m(2) over 3 hours followed by cisplatin 75 mg/m(2), both intravenously, every 21 days. Cycles were repeated every 21 days until progression or a maximum of six cycles. RESULTS: Twenty-six patients obtained an objective response, for an overall response rate of 50% (95% confidence interval, 36% to 64%). Four patients achieved complete clinical responses. The median overall survival time for the group was 10.6 months. Toxicity was moderate, with granulocytopenia and neurotoxicity being the most common side effects noted. CONCLUSION: The combination of cisplatin and paclitaxel is active in advanced urothelial cancer. Responses in visceral, nodal, and soft tissues sites were observed. Granulocytopenia without fever and grade 2/3 neurotoxicity were common. The confidence interval of the overall response rate in this study overlaps most of the other reported regimens. The optimal therapy for advanced urothelial cancer remains undefined. 相似文献
989.
990.
The incidence of adenocarcinoma of the esophagus and gastric cardia is increasing. Many factors are presumed to be associated: symptoms of gastroesophageal reflux disease, tobacco use, alcohol consumption, dietary factors, and obesity. A recent large population-based case-control study evaluated the association between dietary fiber intake and cancers of the gastric cardia and esophagus. This interesting study indicated that high intake of cereal fiber may significantly decrease the risk of gastric cardia cancer. More research is needed on this topic in the hope that dietary intake may decrease the incidence of these cancers. 相似文献