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1.
An Acad Bras Cienc ; 94(suppl 1): e20210633, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35508021

RESUMO

This paper documents an increase in the number of observed explosive cyclones (EC) at King George Island, South Shetland Islands, Antarctica, over the 1989‒2020 period. In ECs at 60o latitudes the surface atmospheric pressure drops ≥24 hPA in 24 hours. The annual EC frequency time series shows a significant positive trend of ~2.7 cyclones/decade, with a break in 2003 and average numbers of 7.3 and 11.8 events before and after that break, respectively. The increase follows closely earlier documented global sea surface temperature (SST) anomaly trends for the 1981‒2018 period, partially attributed to global warming and to the Pacific Decadal Oscillation (PDO). Connections between EC frequency and SST might occur through variations in SST in the southeastern Pacific and southwestern Atlantic, with anomalous cold conditions favoring an increase in ECs. We also found close relations between the number of ECs with simultaneous occurrences of PDO and Atlantic multidecadal oscillation in opposite phases, so that after 2003 they were in the cold and warm phases, respectively, and vice-versa before 2003. Both low-frequency modes seem to modulate the number of ECs. As per the authors knowledge these results have not been discussed before and may help climate modeling studies and weather forecasts.


Assuntos
Tempestades Ciclônicas , Substâncias Explosivas , Temperatura , Fatores de Tempo , Tempo (Meteorologia)
2.
Biomed Res Int ; 2013: 152052, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23484083

RESUMO

Clostridium difficile is a major cause of antibiotic-associated colitis and is associated with significant morbidity and mortality. Glutamine (Gln) is a major fuel for the intestinal cell population. Alanyl-glutamine (Ala-Gln) is a dipeptide that is highly soluble and well tolerated. IEC-6 cells were used in the in vitro experiments. Cell morphology was evaluated by atomic force microscopy (AFM) and scanning electron microscopy (SEM). Cell proliferation was assessed by WST-1 and Ki-67 and apoptosis was assessed by TUNEL. Cytoskeleton was evaluated by immunofluorescence for RhoA and F-actin. RhoA was quantified by immunoblotting. TcdA induced cell shrinkage as observed by AFM, SEM, and fluorescent microscopy. Additionally, collapse of the F-actin cytoskeleton was demonstrated by immunofluorescence. TcdA decreased cell volume and area and increased cell height by 79%, 66.2%, and 58.9%, respectively. Following TcdA treatment, Ala-Gln and Gln supplementation, significantly increased RhoA by 65.5% and 89.7%, respectively at 24 h. Ala-Gln supplementation increased cell proliferation by 137.5% at 24 h and decreased cell apoptosis by 61.4% at 24 h following TcdA treatment. In conclusion, TcdA altered intestinal cell morphology and cytoskeleton organization, decreased cell proliferation, and increased cell apoptosis. Ala-Gln and Gln supplementation reduced intestinal epithelial cell damage and increased RhoA expression.


Assuntos
Toxinas Bacterianas/toxicidade , Dipeptídeos/farmacologia , Enterotoxinas/toxicidade , Células Epiteliais/enzimologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Glutamina/farmacologia , Mucosa Intestinal/enzimologia , Proteína rhoA de Ligação ao GTP/biossíntese , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Tamanho Celular/efeitos dos fármacos , Colite/tratamento farmacológico , Colite/metabolismo , Colite/patologia , Citoesqueleto/metabolismo , Citoesqueleto/patologia , Células Epiteliais/patologia , Mucosa Intestinal/patologia , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Ratos
3.
Acta Crystallogr C ; 68(Pt 11): m312-6, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23124451

RESUMO

The rigid organic linkers N-(4-bromophenylsulfonyl)dithiocarbimate(2-) and N-(4-iodophenylsulfonyl)dithiocarbimate(2-) crystallize with two potassium cations and two water molecules in their asymmetric units, forming the title coordination polymers, [K(2)(C(7)H(4)BrNO(2)S(3))(H(2)O)(2)](n) and [K(2)(C(7)H(4)INO(2)S(3))(H(2)O)(2)](n). The anions and the water molecules link the potassium cations into broad two-dimensional networks, which are further linked by K···halide interactions.

4.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 1): m33-4, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22259336

RESUMO

The title salt, (C(24)H(20)P)(2)[Zn(C(2)F(3)NO(2)S(3))(2)], consists of a complex dianion and two tetra-phenyl-phospho-nium cations. The Zn(II) ion displays a distorted tetra-hedral coordination environment with four S atoms from two S,S'-chelated N-(trifluoro-methyl-sulfonyl-)dithio-carbimate anions. In the crystal, besides the ionic inter-action of the oppositely charged ions, inter-molecular C-H⋯O inter-actions between cations and anions are observed. One of the cations inter-acts with an inversion-related equivalent by π-π stacking between phenyl rings, with a centroid-centroid distance of 3.932 (4) Å.

5.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 3): m251, 2010 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-21580206

RESUMO

In the title salt, (C(24)H(20)P)(2)[Pt(C(7)H(3)Cl(2)NO(2)S(3))(2)], the Pt(II) ion (site symmetry ) is coordinated by two S,S'-bidentate N-(2,5-dichloro-phenyl-sulfon-yl)dithio-carbimate ligands, resulting in a slightly distorted PtS(4) square-planar geometry. In the crystal, a C-H⋯O inter-action is observed, as well as electrostatic attraction between the oppositely charged ions.

6.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 8): m971-2, 2010 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-21588196

RESUMO

The asymmetric unit of the title compound, (C(24)H(20)P)(2)[Pt(C(7)H(5)NO(2)S(3))(2)]·H(2)O, consists of two tetra-phenyl-phospho-nium cations, two half bis-[N-(phenyl-sulfon-yl)dithio-carbim-ato]platinate(II) dianions and one water mol-ecule. The anions are completed by crystallographic inversion symmetry associated with the central Pt(II) ion. The Pt(II) ion is doubly S,S'-chelated by two symmetry-related phenyl-sulfonyl-dithio-carbimate ligands, forming a slightly distorted square-planar configuration. Besides the electrostatic attraction between oppositely charged ions in the crystal packing, intra-molecular C-H⋯O and several inter-molecular C-H⋯O, C-H⋯N and O-H⋯O hydrogen-bonding inter-actions between the cations, anions and water mol-ecules are observed.

7.
J Inorg Biochem ; 103(7): 1045-53, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19505726

RESUMO

Five new compounds with the general formula of (Bu(4)N)(2)[M(RSO(2)NCS(2))(2)], where Bu(4)N=tetrabutylammonium cation, (M=Ni, R=4-FC(6)H(4)) (1), (M=Zn, R=4-FC(6)H(4), 4-ClC(6)H(4), 4-BrC(6)H(4), 4-IC(6)H(4)), (2), (3), (4) and (5), respectively, were obtained by the reaction of the appropriate potassium N-R-sulfonyldithiocarbimate (RSO(2)N=CS(2)K(2)) with nickel(II) chloride hexahydrate or zinc(II) acetate dihydrate in metanol:water 1:1. The elemental analyses and the IR data are consistent with the formation of the expected bis(dithiocarbimato)metal(II) complexes. The (1)H and (13)C NMR spectra showed the signals for the tetrabutylammonium cation and the dithiocarbimate moieties. The compounds 1, 2 and 5 were also characterized by X-ray diffraction techniques. The nickel(II) is coordinated by two N-4-fluorophenylsulphonyldithiocarbimato(2-) ligands forming a planar coordination. The zinc(II) exhibits distorted tetrahedral configuration in compounds 2 and 5 due to the chelation effect of two sulfur atoms of the N-R-sulfonyldithiocarbimate ligands. The antifungal activities of the compounds were tested in vitro against Colletotrichum gloeosporioides, an important fungus that causes the plant disease known as anthracnose in fruit trees. All the complexes were active.


Assuntos
Antifúngicos/química , Antifúngicos/farmacologia , Níquel/química , Compostos Organometálicos/síntese química , Compostos Organometálicos/farmacologia , Zinco/química , Antifúngicos/síntese química , Colletotrichum/efeitos dos fármacos , Cristalografia por Raios X , Estrutura Molecular , Compostos Organometálicos/química , Difração de Raios X
8.
Arq Neuropsiquiatr ; 67(1): 62-8, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19330214

RESUMO

We evaluated the safety and effectiveness of botulinum toxin A (BoNT/A) in the treatment of spasticity in 20 children with spastic diplegic cerebral palsy (CP). All the patients received injections in the gastrocnemius and soleus, and 15 received injections in the adductors. The total dose varied from 70 to 140 U (99.75+/-16.26 U), or 7.45+/-2.06 U/kg per patient. The treatment improved the patients' walking and gait pattern significantly. There was also a significant alteration in the heel-ground distance and increased motion of the ankle joint. These structural changes in the feet were sustained until the end of the follow-up, although the same was not observed for the functional parameters. Three patients complained of weakness in the lower limbs. In conclusion, BoNT/A is safe and effective when used in a single session of injections and produces a sustained structural modification of the lower limbs. However, functional changes are temporary and are only observed during the peak effect of the drug.


Assuntos
Toxinas Botulínicas Tipo A/administração & dosagem , Paralisia Cerebral/tratamento farmacológico , Fármacos Neuromusculares/administração & dosagem , Adolescente , Paralisia Cerebral/complicações , Criança , Pré-Escolar , Feminino , Seguimentos , Marcha/efeitos dos fármacos , Humanos , Lactente , Extremidade Inferior/fisiopatologia , Masculino , Espasticidade Muscular/tratamento farmacológico , Tono Muscular/efeitos dos fármacos , Estatísticas não Paramétricas , Resultado do Tratamento
9.
Arq. neuropsiquiatr ; 67(1): 62-68, Mar. 2009. graf, tab
Artigo em Inglês | LILACS | ID: lil-509110

RESUMO

We evaluated the safety and effectiveness of botulinum toxin A (BoNT/A) in the treatment of spasticity in 20 children with spastic diplegic cerebral palsy (CP). All the patients received injections in the gastrocnemius and soleus, and 15 received injections in the adductors. The total dose varied from 70 to 140 U (99.75±16.26 U), or 7.45±2.06 U/kg per patient. The treatment improved the patients' walking and gait pattern significantly. There was also a significant alteration in the heel-ground distance and increased motion of the ankle joint. These structural changes in the feet were sustained until the end of the follow-up, although the same was not observed for the functional parameters. Three patients complained of weakness in the lower limbs. In conclusion, BoNT/A is safe and effective when used in a single session of injections and produces a sustained structural modification of the lower limbs. However, functional changes are temporary and are only observed during the peak effect of the drug.


Para avaliação da segurança e eficácia do tratamento com toxina botulínica A (TB-A) na espasticidade na paralisia cerebral (PC), foram selecionadas 20 crianças com a forma diplegia espástica. Todos os pacientes receberam injeções nos gastrocnêmios e sóleos, 15 receberam doses nos adutores da coxa. A dose total variou de 70 a 140 Us (99,75±16,26 U), 7,45±2,06 U/Kg por paciente. O tratamento com a TB-A melhorou significativamente a deambulação e o padrão de marcha. Houve também significativa alteração da distância tornozelo-solo e aumento da amplitude de movimento da articulação do tornozelo. Essas mudanças estruturais dos pés se mantiveram até o final do acompanhamento. O mesmo não foi observado com parâmetros funcionais. Três pacientes apresentaram fraqueza em membros inferiores. Conclui-se que a TB-A, em uma única aplicação, é segura e eficaz. Há modificação sustentada da estrutura motora dos membros inferiores, porém mudanças funcionais são temporárias, durante o pico de ação do medicamento.


Assuntos
Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Toxinas Botulínicas Tipo A/administração & dosagem , Paralisia Cerebral/tratamento farmacológico , Fármacos Neuromusculares/administração & dosagem , Paralisia Cerebral/complicações , Seguimentos , Marcha/efeitos dos fármacos , Extremidade Inferior/fisiopatologia , Espasticidade Muscular/tratamento farmacológico , Tono Muscular/efeitos dos fármacos , Estatísticas não Paramétricas , Resultado do Tratamento
10.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 10): m1154-5, 2009 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-21577695

RESUMO

In the title complex, (C(24)H(20)P)(2)[Sn(C(2)H(3)NO(2)S(3))(3)], the Sn(IV) atom is coordinated by three N-(methyl-sulfon-yl)dithio-carbimate bidentate ligands through the anionic S atoms in a slightly distorted octa-hedral coordination geometry. There is one half-mol-ecule in the asymmetric unit; the complex is located on a crystallographic twofold rotation axis passing through the cation and bis-ecting one of the (non-symmetric) ligands, which appears thus disordered over two sites of equal occupancy. In the crystal structure, weak inter-molecular C-H⋯O and C-H⋯S inter-actions contribute to the packing stabilization.

11.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 1): m148-9, 2007 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-21200502

RESUMO

The Ni atom in the title complex, (C(24)H(20)P)(2)[Ni(C(9)H(17)NO(2)S(3))(2)], lies on a twofold axis within a square-planar geometry defined by four S atoms derived from two dithio-carbimate dianions, each forming a four-membered chelate ring. A small distortion, described by a deviation of the Ni(II) atom by 0.083 (1) Šfrom the plane through the four S atoms, and also by the torsion angles about the Ni-S bonds, implies a folded conformation for the chelate ring.

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