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1.
Biomed Sci Instrum ; 51: 332-40, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25996736

RESUMO

In this work, the ventricles in MR brain images are segmented using edge based modified Distance Regularized Level Set Evolution (DRLSE) method and the structural changes in the disease is further analysed using Minkowski functionals (MFs). Twenty normal and abnormal T1-weighted coronal mid slice MR image are considered for the analysis. The MR brain image is pre-processed using contrast enhancement method. The edge based modified DRLSE with a new penalty term is used to segment the ventricles from the enhanced images. The results of the level set method are compared with geodesic active contour method. The segmentation results are validated using ZSI (Zijdenbos Similarity Index) and F-score. The Minkowski functionals such as MF-area, MF-perimeter and MF-Euler number are calculated from the extracted ventricle region. The longitudinal analysis of ventricles is performed using these features. The results show that the DRLSE based level set method is able to extract the ventricle edges with less discontinuity. The F-score and ZSI is high for DRLSE (0.83 and 0.84) compared to geodesic method (0.79 and 0.80). The MF-area is able to discriminate the controls and the AD subjects with high statistical significance (p < 0.001). This analysis also shows that the MF- area increases with severity. These results could be used for the study of discrimination and progression of the Alzheimer's disease like disorders.

2.
Acta Crystallogr E Crystallogr Commun ; 71(Pt 2): o119-20, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-25878861

RESUMO

In the title compound, C21H15NO3, the mol-ecule has an E conformation about the C=C bond, and the C-C=C-C torsion angle is -178.24 (18)°. In the mol-ecule, the planes of the terminal rings are twisted by an angle of 42.19 (10)°, while the biphenyl part is not planar, with a dihedral angle between the rings of 39.2 (1)°. The dihedral angle between the nitro-phenyl ring and the inner benzene ring is 5.56 (9)°. The 3-nitro group is approximately coplanar with the benzene ring to which it is attached [O-N-C-C = 0.1 (3)°]. In the crystal, mol-ecules are linked via C-H⋯π inter-actions, involving the terminal benzene rings, forming corrugated layers parallel to (100).

3.
Acta Crystallogr E Crystallogr Commun ; 71(Pt 1): 1-3, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25705435

RESUMO

The title compound, C22H17NO4, crystallizes with two independent mol-ecules (A and B) in the asymmetric unit. Each mol-ecule exists as an E isomer with C-C=C-C torsion angles of -175.69 (17) and -178.41 (17)° in A and B, respectively. In mol-ecule A, the planes of the terminal benzene rings are twisted by an angle of 26.67 (10)°, while the biphenyl unit is non-planar, the dihedral angle between the rings being 30.81 (10)°. The dihedral angle between the nitro-phenyl ring and the inner phenyl ring is 6.50 (9)°. The corresponding values in mol-ecule B are 60.61 (9), 31.07 (8) and 31.05 (9)°. In the crystal, mol-ecules are arranged in a head-to-head manner, with the 3-nitro-phenyl groups nearly parallel to one another. The A and B mol-ecules are linked to one another via C-H⋯O hydrogen bonds, forming chains lying parallel to (-320) and enclosing R 2 (2)(10) and R 2 (2)(12) ring motifs. The meth-oxy group in both mol-ecules is positionally disordered with a refined occupancy ratio of 0.979 (4):0.021 (4) for mol-ecule A and 0.55 (4):0.45 (4) for mol-ecule B.

4.
Acta Crystallogr E Crystallogr Commun ; 71(Pt 1): o65-6, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25705513

RESUMO

In the title compound, C22H17NO3, the mol-ecule has an E conformation about the C=C bond, and the C-C=C-C torsion angle is -177.7 (3)°. The planes of the terminal benzene rings are twisted by 41.62 (16)°, while the biphenyl unit is non-planar, the dihedral angle between the planes of the rings being 38.02 (15)°. The dihedral angle between the nitro-phenyl ring and the inner benzene ring is 5.29 (16)°. In the crystal, mol-ecules are linked by two weak C-H⋯π inter-actions, forming rectangular tubes propagating along the b-axis direction.

5.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 8): o838, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-25249891

RESUMO

The title compound, C21H14O3, crystallizes with eight independent mol-ecules (A-H) in the asymmetric unit which are arranged in four groups of two mol-ecules each (AB, CD, EF and GH). In each mol-ecule, the pyran-2-one ring is planar (r.m.s. deviations vary from 0.001 to 0.017 Å), while the pyran ring has a screw-boat conformation. In the crystal, mol-ecules stack in two columns, along the [10-1] direction, composed of mol-ecules C, B, E and G, and D, A, F and H. Mol-ecules A and F are linked via C-H⋯O hydrogen bonds. In addition, there are a number of C-H⋯π contacts present involving all of the mol-ecules. These inter-actions result in the formation of a three-dimensional network.

6.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 7): o809-10, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25161590

RESUMO

In the title mol-ecule, C22H18O, the o-tolyl ring is connected through a conjugated double bond. The mol-ecule adopts an E conformation and the C-C=C-C torsion angle is 178.77 (13)°. The overall conformation may be described by the values of dihedral angles between the different planes. The terminal rings are twisted by an angle of 54.75 (8)°, while the biphenyl part is not planar, the dihedral angle between the planes of the rings being 40.65 (8)°. The dihedral angle between the benzene rings is 14.10 (7)°. There are three weak C-H⋯π inter-actions found in the crystal structure. No classic hydrogen bonds are observed.

7.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 12): o1268-9, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25553038

RESUMO

In the title compound, C24H14Cl2N2O2S, the 2H-chromene ring system is approximately planar, with a maximum deviation of 0.025 (2) Å. The thia-zole ring is almost planar, with an r.m.s. deviation of 0.0022 Å, and makes a dihedral angle of 58.52 (7)° with the chromene ring system. The chromene ring system is inclined at angles of 58.3 (1) and 55.39 (9)° with respect to the two chloro-phenyl rings. The two chloro-phenyl rings show significant deviation from coplanarity, with a dihedral angle between them of 47.69 (8)°. The crystal structure features C-H⋯Cl inter-actions extending in (100) and propagating along the a-axis direction and weak π-π inter-actions [centroid-centroid separation = 3.867 (2) Å].

8.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 2): o280, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23424553

RESUMO

In the racemic title compound, C(22)H(21)NO(3), the nitro-gen-containing ring of the pyran-oquinoline moiety adopts a slightly distorted half-chair conformation and the oxygen-containing ring adopts a slightly distorted chair conformation. The benzene rings make a dihedral angle of 84.97 (8)°. In the crystal, weak C-H⋯O inter-actions link the mol-ecules into chains extending along the a-axis direction.

9.
Artigo em Inglês | MEDLINE | ID: mdl-24426982

RESUMO

In the title compound, [Mg(C3H3N2)4(H2O)2]Cl2, the Mg(II) cation lies on a crystallographic inversion centre and is coordinated by two water mol-ecules and four N-atom donors from monodentate imidazole ligands, giving a slightly distorted octa-hedral stereochemistry. In the crystal, water O-H⋯Cl and imidazole N-H⋯Cl hydrogen bonds give rise to a three-dimensional structure.

10.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 10): o3008, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23125779

RESUMO

In the title compound, C(10)H(10)ClNO, the benzoisoxazole ring is almost planar (r.m.s. deviation = 0.0121 Å) and the chloro substituent in the side chain is anti-clinal relative to the N-C bond of the isoxazole ring. In the crystal, adjacent mol-ecules are linked via a pair of weak C-H⋯N hydrogen bonds, forming dimers through a cyclic R(2) (2)(8) association.

11.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 11): o2999, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22220017

RESUMO

The title compound, C(15)H(12)ClNO, is a functionalized 1,2-benzoxazole with a chloro-(phen-yl)methyl substituent. The mol-ecule is V-shaped, the dihedral angle between the mean plane of the 1,2-benzoxazole system [maximum deviation = 0.023 (3) Šfor the N atom] and the phenyl ring being 70.33 (14)°. There are no hydrogen-bonding inter-actions in the crystal structure, which is stabilized by van der Waals inter-actions only.

12.
Clin Chim Acta ; 326(1-2): 143-9, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12417105

RESUMO

BACKGROUND: Our aim was to examine the structural integrity of red blood cells in cervical cancer patients by measuring the concentrations of thiobarbituric acid reactive substances (TBARS), antioxidant status, cholesterol/phospholipid (C/P) molar ratio, enzyme activity and osmotic fragility of erythrocytes. METHODS: This study has been conducted on 32 adult female cervical cancer patients and an equal number of age- and sex-matched normal subjects. Erythrocyte concentrations of lipids, TBARS, vitamin E, reduced glutathione and enzymic activities of catalase and Na(+)K(+)-ATPase were measured as well as plasma concentrations of sodium and potassium. The present study also examined the changes in erythrocyte osmotic fragility in cervical cancer patients and normal subjects. The red cell fluidity and permeability were determined by estimating the C/P ratio and Na(+)K(+)-ATPase activity, respectively. RESULTS: The release of thiobarbituric acid reactive substances was significantly higher in cervical cancer patients as compared to normal subjects. The increased lipid peroxidation with concomitant decrease in antioxidants was notable in cervical cancer patients. Red blood cells of cervical cancer patients were more fragile than those from normal subjects. Increase in red cell membrane C/P ratio and Na(+)K(+)-ATPase activity was noticed in cervical cancer patients as compared to normal subjects. CONCLUSIONS: Increased lipid peroxidation, insufficient antioxidant potential and changes in C/P molar ratio as well as activity of Na(+)K(+)-ATPase cause structural and functional abnormalities in the erythrocytes of cervical cancer patients.


Assuntos
Antioxidantes/metabolismo , Membrana Eritrocítica/metabolismo , Eritrócitos/metabolismo , Lipídeos/sangue , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Neoplasias do Colo do Útero/sangue , Adulto , Antioxidantes/análise , Colesterol/sangue , Membrana Eritrocítica/enzimologia , Eritrócitos/enzimologia , Feminino , Humanos , Peroxidação de Lipídeos/fisiologia , Lipídeos de Membrana/sangue , Pessoa de Meia-Idade , Fragilidade Osmótica , Fosfolipídeos/sangue , ATPase Trocadora de Sódio-Potássio/sangue , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Neoplasias do Colo do Útero/enzimologia
13.
J Biochem Mol Biol Biophys ; 6(3): 225-7, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12186759

RESUMO

The present study examined the relationship between lipid peroxidation and antioxidant status in plasma, erythrocyte and erythrocyte membrane of cervical cancer patients and an equal number of age and sex matched normal subjects as well as patients with cervicitis. Lipid peroxidation was significantly increased with concomitant decrease in antioxidant levels in cervical cancer patients as compared to normal subjects and patients with cervicitis. The elevated lipid peroxidation and disturbed antioxidant status was also noticed in cervicitis patients as compared to normal subjects. This increase in lipid peroxidation can be attributed to possible breakdown of antioxidant mechanisms in cervicitis and cervical cancer patients.


Assuntos
Antioxidantes/farmacologia , Peroxidação de Lipídeos , Neoplasias do Colo do Útero/metabolismo , Adulto , Membrana Celular/metabolismo , Eritrócitos/metabolismo , Feminino , Humanos , Pessoa de Meia-Idade , Estresse Oxidativo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Cervicite Uterina/metabolismo
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