993 resultados para LI-7(N,GAMMA)LI-8


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The X-ray crystal structures of (I), the base 4030W92, 5-(2,3-dichlorophenyl)-2,4-diamino-6-fluoromethyl-pyrimidine, C11H9Cl2FN4, and (II) 227C89, the methanesulphonic acid salt of 5-(2,6-dichlorophenyl)-1-H-2,4-diamino-6-methyl-pyrimidine, C11H11Cl2N4 center dot CH3O3S, have been carried out at low temperature. A detailed comparison of the two structures is given. Structure (I) is non-centrosymmetric, crystallizing in space group P2(1) with unit cell a = 10.821(3), b = 8.290(3), c = 13.819(4) angstrom, beta = 105.980(6)degrees, V = 1191.8(6) angstrom(3), Z = 4 (two molecules per asymmetric unit) and density (calculated) = 1.600 mg/m(3). Structure (II) crystallizes in the triclinic space group P (1) over bar with unit cell a = 7.686(2), b = 8.233(2), c = 12.234(2) angstrom, alpha = 78.379(4), beta = 87.195(4), gamma = 86.811(4)degrees, V = 756.6(2) angstrom(3), Z = 2, density (calculated) = 1.603 mg/m(3). Final R indices [I > 2sigma(I)] are R1 = 0.0572, wR2 = 0.1003 for (I) and R1 = 0.0558, wR2 = 0.0982 for (II). R indices (all data) are R1 = 0.0983, wR2 = 0.1116 for (I) and R1 = 0.1009, wR2 = 0.1117 for (II). 5- Phenyl-2,4 diaminopyrimidine and 6-phenyl-1,2,4 triazine derivatives, which include lamotrigine (3,5-diamino-6-(2,3-dichlorophenyl)-1,2,4-triazine), have been investigated for some time for their effects on the central nervous system. The three dimensional structures reported here form part of a newly developed data base for the detailed investigation of members of this structural series and their biological activities.

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Object
Trigeminal neuralgia pain causes severe disability. Stereotactic radiosurgery is the least invasive surgical option for patients with trigeminal neuralgia. Since different medical and surgical options have different rates of pain relief and morbidity, it is important to evaluate longer-term outcomes.

Methods
The authors retrospectively reviewed outcomes in 503 medically refractory patients with trigeminal neuralgia who underwent Gamma Knife surgery (GKS). The median patient age was 72 years (range 26–95 years). Prior surgery had failed in 205 patients (43%). The GKS typically was performed using MR imaging guidance, a single 4-mm isocenter, and a maximum dose of 80 Gy.

Results
Patients were evaluated for up to 16 years after GKS; 107 patients had > 5 years of follow-up. Eighty-nine percent of patients achieved initial pain relief that was adequate or better, with or without medications (Barrow Neurological Institute [BNI] Scores I–IIIb). Significant pain relief (BNI Scores I–IIIa) was achieved in 73% at 1 year, 65% at 2 years, and 41% at 5 years. Including Score IIIb (pain adequately controlled with medication), a BNI score of I–IIIb was found in 80% at 1 year, 71% at 3 years, 46% at 5 years, and 30% at 10 years. A faster initial pain response including adequate and some pain relief was seen in patients with trigeminal neuralgia without additional symptoms, patients without prior surgery, and patients with a pain duration of = 3 years. One hundred ninety-three (43%) of 450 patients who achieved initial pain relief reported some recurrent pain 3–144 months after initial relief (median 50 months). Factors associated with earlier pain recurrence that failed to maintain adequate or some pain relief were trigeminal neuralgia with additional symptoms and = 3 prior failed surgical procedures. Fifty-three patients (10.5%) developed new or increased subjective facial paresthesias or numbness and 1 developed deafferentation pain; these symptoms resolved in 17 patients. Those who developed sensory loss had better long-term pain control (78% at 5 years).

Conclusions
Gamma Knife surgery proved to be safe and effective in the treatment of medically refractory trigeminal neuralgia and is of value for initial or recurrent pain management. Despite the goal of minimizing sensory loss with this procedure, some sensory loss may improve long-term outcomes. Pain relapse is amenable to additional GKS or another procedure.

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Tetrasomy, pentasomy, and hexasomy 8 (polysomy 8) are relatively rare compared to trisomy 8. Here we report on a series of 12 patients with acute myeloid leukemia (AML), myelodysplastic syndrome (MDS), or myeloproliferative disorder (MPD) associated with polysomy 8 as detected by conventional cytogenetics and fluorescence in situ hybridization (FISH). In an attempt to better characterize the clinical and hematological profile of this cytogenetic entity, our data were combined with those of 105 published patients. Tetrasomy 8 was the most common presentation of polysomy 8. In 60.7% of patients, polysomy 8 occurred as part of complex changes (16.2% with 11q23 rearrangements). No cryptic MLL rearrangements were found in cases in which polysomy 8 was the only karyotypic change. Our study demonstrates the existence of a polysomy 8 syndrome, which represents a subtype of AML, MDS, and MPD characterized by a high incidence of secondary diseases, myelomonocytic or monocytic involvement in AML and poor overall survival (6 months). Age significantly reduced median survival, but associated cytogenetic abnormalities did not modify it. Cytogenetic results further demonstrate an in vitro preferential growth of the cells with a high level of aneuploidy suggesting a selective advantage for polysomy 8 cells.

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Heavy-ion total reaction cross-section measurements for more than 1100 reaction cases covering 61 target nuclei in the range (6)Li-(238)U and 158 projectile nuclei from (2)H to (84)Kr (mostly exotic ones) have been analyzed in a systematic way by using an empirical, three-parameter formula that is applicable to the cases of projectile kinetic energies above the Coulomb barrier. The analysis has shown that the average total nuclear binding energy per nucleon of the interacting nuclei and their radii are the chief quantities that describe the cross-section patterns. A great amount of cross-section data (87%) has been quite satisfactorily reproduced by the proposed formula; therefore, the total reaction cross-section predictions for new, not yet experimentally investigated reaction cases can be obtained within 25% (or much less) uncertainty.

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Objective: Our objective was to delineate the potential role of adipogenesis in insulin resistance and type 2 diabetes. Obesity is characterized by an increase in adipose tissue mass resulting from enlargement of existing fat cells (hypertrophy) and/or from increased number of adipocytes (hyperplasia). The inability of the adipose tissue to recruit new fat cells may cause ectopic fat deposition and insulin resistance.

Research Methods and Procedures: We examined the expression of candidate genes involved in adipocyte proliferation and/or differentiation [ CCAAT/enhancer-binding protein (C/EBP) alpha, C/EBPdelta, GATA domain-binding protein 3 (GATA3), C/EBPbeta, peroxisome proliferator-activated receptor (PPAR) gamma2, signal transducer and activator of transcription 5A (STAT5A), Wnt-10b, tumor necrosis factor alpha, sterol regulatory element-binding protein 1c (SREBP1c), 11 beta-hydroxysteroid dehydrogenase, PPARG angiopoietin-related protein (PGAR), insulin-like growth factor 1, PPARitalic gamma coactivator 1alpha, PPARitalic gamma coactivator 1beta, and PPARdelta] in subcutaneous adipose tissue from 42 obese individuals with type 2 diabetes and 25 non-diabetic subjects matched for age and obesity.

Results: Insulin sensitivity was measured by a 3-hour 80 mU/m2 per minute hyperinsulinemic glucose clamp (100 mg/dL). As expected, subjects with type 2 diabetes had lower glucose disposal (4.9 plusminus 1.9 vs. 7.5 plusminus 2.8 mg/min per kilogram fat-free mass; p < 0.001) and larger fat cells (0.90 plusminus 0.26 vs. 0.78 plusminus 0.17 mum; p = 0.04) as compared with obese control subjects. Three genes (SREBP1c, p < 0.01; STAT5A, p = 0.02; and PPARitalic gamma2, p = 0.02) had significantly lower expression in obese type 2 diabetics, whereas C/EBPbeta only tended to be lower (p = 0.07).

Discussion: This cross-sectional study supports the hypothesis that impaired expression of adipogenic genes may result in impaired adipogenesis, potentially leading to larger fat cells in subcutaneous adipose tissue and insulin resistance.

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We studied the correlation among cellular immune response, the pattern of lung granulomatous lesions and alterations in spleen lymphoid structure in Swiss mice inoculated intravenously with Paracoccidioides brasiliensis strain 18. The animals were evaluated at 24, 48 and 96 h after infection and further studied weekly for 18 weeks by: (i) the macrophage migration inhibition test with phytohemagglutinin (PHA) and P. brasiliensis antigen (PbAg); and (ii) histopathology of the lung and spleen lesions. One group of animals was gamma -irradiated (8 Gy), infected under the same conditions and evaluated for the pattern of lung granulomatous lesions and spleen lymphoid structure at 24, 48 and 96 h after infection. During the first week of infection, the non-irradiated animals presented a positive response to PHA and PbAg, compact granulomas in the lungs and a typical hyperplasia of the spleen white pulp. However, from weeks 2 to 5, a depression of the cell-mediated immunity (CMI) response to PHA and PbAg was observed in association with granulomas presenting only large mononuclear cells and lacking both giant cells and a peripheral halo of small mononuclear cells. This pattern of granuloma formation was similar to that seen in gamma -irradiated animals, whose cells involved in CMI were absent. After week 7, the non-irradiated animals showed granulomas characterized by the presence of giant cells and a peripheral halo of small mononuclear cells. This type of granuloma was formed concomitantly with recovery of the CMI and of the lymphoid structure of the spleen. The results showed a correlation among granulomas composed of large mononuclear cells, hypoplasia of the splenic tissue and impaired CMI. This correlation indicated that although granuloma morphogenesis per se does not depend on the activation of CMI, this response is important at later stages during modulation of the cellular composition of the granulomas.

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DEP domain-containing mTOR-interacting protein (DEPTOR) inhibits the mechanistic target of rapamycin (mTOR), but its in vivo functions are unknown. Previous work indicates that Deptor is part of the Fob3a quantitative trait locus (QTL) linked to obesity/leanness in mice, with Deptor expression being elevated in white adipose tissue (WAT) of obese animals. This relation is unexpected, considering the positive role of mTOR in adipogenesis. Here, we dissected the Fob3a QTL and show that Deptor is the highest-priority candidate promoting WAT expansion in this model. Consistently, transgenic mice overexpressing DEPTOR accumulate more WAT. Furthermore, in humans, DEPTOR expression in WAT correlates with the degree of obesity. We show that DEPTOR is induced by glucocorticoids during adipogenesis and that its overexpression promotes, while its suppression blocks, adipogenesis. DEPTOR activates the proadipogenic Akt/PKB-PPAR-gamma axis by dampening mTORC1-mediated feedback inhibition of insulin signaling. These results establish DEPTOR as a new regulator of adipogenesis.

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Background: Mechanisms linking behavioral stress and inflammation are poorly understood, mainly in distal lung tissue. Objective: We have investigated whether the forced swim stress (FS) could modulate lung tissue mechanics, iNOS, cytokines, oxidative stress activation, eosinophilic recruitment, and remodeling in guinea pigs (GP) with chronic pulmonary inflammation. Methods: The GP were exposed to ovalbumin or saline aerosols (2x/wk/4wks, OVA, and SAL). Twenty-four hours after the 4th inhalation, the GP were submitted to the FS protocol (5x/wk/2wks, SAL-S, and OVA-S). Seventy-two hours after the 7th inhalation, lung strips were cut and tissue resistance (Rt) and elastance (Et) were obtained (at baseline and after OVA and Ach challenge). Strips were submitted to histopathological evaluation. Results: The adrenals' weight, the serum cortisol, and the catecholamines were measured. There was an increase in IL-2, IL-5, IL-13, IFN-gamma, iNOS, 8-iso-PGF2 alpha, and in %Rt and %Et after Ach challenge in the SAL-S group compared to the SAL one. The OVA-S group has had an increase in %Rt and %Et after the OVA challenge, in %Et after the Ach and in IL-4, 8-iso-PGF2 alpha, and actin compared to the OVA. Adrenal weight and cortisol serum were increased in stressed animals compared to nonstressed ones, and the catecholamines were unaltered. Conclusion & clinical relevance: Repeated stress has increased distal lung constriction, which was associated with an increase of actin, IL-4, and 8-iso-PGF2 alpha levels. Stress has also induced an activation of iNOS, cytokines, and oxidative stress pathways.

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Background: Endoscopic retrograde cholangiopancreatography may fail because of malignant involvement of the second portion of the duodenum and the major papilla. Alternatives include percutaneous transhepatic biliary drainage (PTBD) or surgical bypass. Endoscopic ultrasonography-guided choledochoduodenostomy (EUS-CD) has been reported as an alternative. Objective: To prospectively compare EUS-CD and PTBD in patients with unresectable malignant biliary obstruction. Design: Prospective and randomized study. Setting: Tertiary center. Main Outcome Measurements: Success and efficacy comparison EUS-CD with PTBD. Results: Twenty-five subjects were randomized (13 EUS-CD and 12 PTBD). Mean age was 67 years (SD, 11.9). The 2 groups were similar before intervention in terms of quality of life [EUS-CD (58.3) vs. PTBD (57.8); P = 0.78], total bilirubin (16.4 vs. 17.2; P = 0.7), alkaline phosphatase (539 vs. 518; P = 0.7), and gamma-glutamyl transferase (554.3 vs. 743.5; P = 0.56). All procedures were technically and clinically successful in both groups. At 7-day follow-up there was a significant reduction in total bilirubin in both the groups (EUS-CD, 16.4 to 3.3; P = 0.002 and PTBD, 17.2 to 3.8; P = 0.01), although no difference was noted comparing the 2 groups (EUS-CD to PTBD; 3.3 vs. 3.8; P = 0.2). There was no difference between the complication rates in the 2 groups (P = 0.44), EUS-CD (2/13; 15.3%) and PTBD (3/12; 25%). Costs were similar in the 2 groups also ($5673-EUS-CD vs. $7570-PTBD; P = 0.39). Limitations: Small sample size and single center study. Conclusions: EUS-CD can be an effective and safe alternative to PTBD with similar success, complication rate, cost, and quality of life.

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Peroxynitrite, a powerful mutagenic oxidant and nitrating species, is formed by the near diffusion-limited reaction of .NO and O2.- during activation of phagocytes. Chronic inflammation induced by phagocytes is a major contributor to cancer and other degenerative diseases. We examined how gamma-tocopherol (gammaT), the principal form of vitamin E in the United States diet, and alpha-tocopherol (alphaT), the major form in supplements, protect against peroxynitrite-induced lipid oxidation. Lipid hydroperoxide formation in liposomes (but not isolated low-density lipoprotein) exposed to peroxynitrite or the .NO and O2.- generator SIN-1 (3-morpholinosydnonimine) was inhibited more effectively by gammaT than alphaT. More importantly, nitration of gammaT at the nucleophilic 5-position, which proceeded in both liposomes and human low density lipoprotein at yields of approximately 50% and approximately 75%, respectively, was not affected by the presence of alphaT. These results suggest that despite alphaT's action as an antioxidant gammaT is required to effectively remove the peroxynitrite-derived nitrating species. We postulate that gammaT acts in vivo as a trap for membrane-soluble electrophilic nitrogen oxides and other electrophilic mutagens, forming stable carbon-centered adducts through the nucleophilic 5-position, which is blocked in alphaT. Because large doses of dietary alphaT displace gammaT in plasma and other tissues, the current wisdom of vitamin E supplementation with primarily alphaT should be reconsidered.

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PURPOSE The purpose of this study was to evaluate if osseous correction of the femoral neck achieved arthroscopically is comparable to that achieved by surgical dislocation. METHODS We retrospectively analyzed all patients who were treated with hip arthroscopy or surgical dislocation for cam or mixed type femoroacetabular impingement (FAI) in our institution between 2006 and 2009. Inclusion criteria were complete clinical and radiologic documentation with standardized radiographs. Group 1 consisted of 66 patients (49 female patients, mean age 33.8 years) treated with hip arthroscopy. Group 2 consisted of 135 patients (91 male patients, mean age 31.2 years) treated with surgical hip dislocation. We compared the preoperative and postoperative alpha and gamma angles, as well as the triangular index. Mean follow-up was 16.7 months (range, 2 to 79 months). RESULTS In group 1, the mean alpha angle improved from 60.7° preoperatively to 47.8° postoperatively (P < .001) and the mean gamma angle improved from 47.3° to 44.5° (P < .001). Over time, the preoperative mean alpha angle increased from 56.3° in 2006 to 67.5° in 2009, whereas the postoperative mean alpha angle decreased from 51.2° in 2006 to 47.5° in 2009. In group 2, the mean alpha angle improved from 75.3° preoperatively to 44.8° postoperatively (P < .001), and the mean gamma angle improved from 65.1° to 52.2° (P < .001). Arthroscopic revision of intra-articular adhesions was performed in 4 patients (6.1%) in group 1 and 16 patients (12%) in group 2. Three patients (2.2%) in group 2 underwent revision for nonunion of the greater trochanter. CONCLUSIONS Osseous correction of cam-type FAI with hip arthroscopy is comparable to the correction achieved by surgical hip dislocation. There is a significant learning curve for hip arthroscopy, with postoperative osseous correction showing improved results with increasing surgical experience. LEVEL OF EVIDENCE Level III, retrospective comparative study.

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Shipboard measurements of organohalogen compounds in air and surface seawater were conducted in the Canadian Arctic in 2007-2008. Study areas included the Labrador Sea, Hudson Bay, and the southern Beaufort Sea. High volume air samples were collected at deck level (6 m), while low volume samples were taken at 1 and 15 m above the water or ice surface. Water samples were taken within 7 m. Water concentration ranges (pg/L) were as follows: alpha-hexachlorocyclohexane (alpha-HCH) 465-1013, gamma-HCH 150-254, hexachlorobenzene (HCB) 4.0-6.4, 2,4-dibromoanisole (DBA) 8.5-38, and 2,4,6-tribromoanisole (TBA) 4.7-163. Air concentration ranges (pg/m**3) were as follows: alpha-HCH 7.5-48, gamma-HCH 2.1-7.7, HCB 48-71, DBA 4.8-25, and TBA 6.4-39. Fugacity gradients predicted net deposition of HCB in all areas, while exchange directions varied for the other chemicals by season and locations. Net evasion of alpha-HCH from Hudson Bay and the Beaufort Sea during open water conditions was shown by air concentrations that averaged 14% higher at 1 m than 15 m. No significant difference between the two heights was found over ice cover. The alpha-HCH in air over the Beaufort Sea was racemic in winter (mean enantiomer fraction, EF = 0.504 ± 0.008) and nonracemic in late spring-early summer (mean EF = 0.476 ± 0.010). This decrease in EF was accompanied by a rise in air concentrations due to volatilization of nonracemic alpha-HCH from surface water (EF = 0.457 ± 0.019). Fluxes of chemicals during the southern Beaufort Sea open water season (i.e., Leg 9) were estimated using the Whitman two-film model, where volatilization fluxes are positive and deposition fluxes are negative. The means ± SD (and ranges) of net fluxes (ng/m**2/d) were as follows: alpha-HCH 6.8 ± 3.2 (2.7-13), gamma-HCH 0.76 ± 0.40 (0.26-1.4), HCB -9.6 ± 2.7 (-6.1 to -15), DBA 1.2 ± 0.69 (0.04-2.0), and TBA 0.46 ± 1.1 ng/m**2/d (-1.6 to 2.0).