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1.
Obstet Gynecol ; 143(1): 67-81, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37797337

RESUMO

Neonatal hypoxic-ischemic encephalopathy (HIE) is an important clinical entity because it is associated with death and long-term disability, including cognitive impairment, cerebral palsy, seizures, and neurosensory deficits. Over the past 40 years, there has been an intensive search to identify therapies to improve the prognosis of neonates with HIE. Hypothermia treatment represents the culmination of laboratory investigations including small and large animal studies, followed by pilot human studies, and, finally, randomized controlled trials to establish efficacy and safety. Clinical trials have demonstrated that hypothermia treatment reduces mortality and improves early childhood outcome among survivors. Hypoxic-ischemic encephalopathy is a multi-system disease process that requires intensive medical support for brain monitoring and monitoring of non-central nervous system organ dysfunction. Treatment must be conducted in a level III or IV neonatal intensive care unit with infrastructure for an integrated approach to care for critically ill neonates. Hypothermia treatment is the first and currently the only therapy to improve outcomes for neonates with HIE and indicates that HIE is modifiable. However, outcomes likely can be improved further. Hypothermia treatment has accelerated investigation of other therapies to combine with hypothermia. It has also stimulated a more intensive approach to brain monitoring, which allows earlier intervention for complications. Finally, HIE and hypothermia treatment negatively influences the psychological state of affected families, and there is growing recognition of the importance of trauma-informed principles to guide medical professionals.


Assuntos
Hipotermia Induzida , Hipotermia , Hipóxia-Isquemia Encefálica , Recém-Nascido , Animais , Humanos , Pré-Escolar , Hipóxia-Isquemia Encefálica/terapia , Prognóstico , Convulsões/complicações
2.
Inorg Chem ; 59(18): 13371-13382, 2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-32870665

RESUMO

A new molecular donor-acceptor-donor (D-A-D) triad, comprised of an electron deficient 1,4,5,8-naphthalene tetracarboxylic diimide (NDI) unit covalently connected to two flanking photosensitizers, i.e., a bis-heteroleptic Ru(II) complex of 1,10-phenanthroline and pyridine triazole hybrid ligand, is described. The single crystal X-ray structure of the perchlorate salt of the triad demonstrates that the electron deficient NDI unit can act as a host for anions via anion-π interaction. Detailed solution-state studies indicate that fluoride selectively interacts with the D-A-D triad to form a dianionic NDI, NDI2-, via a radical anion, NDI•-. On the contrary, cyanide reduces the NDI moiety to NDI•-, as confirmed by UV-vis, NMR, and EPR spectroscopy. Further, femtosecond transient absorption spectroscopic studies reveal a low luminescence quantum yield of the D-A-D triad attributable to the photoinduced electron transfer (PET) process from the photoactive Ru(II) center to the NDI unit. Interestingly, the triad displays "OFF-ON" luminescence behavior in the presence of fluoride by restoring the Ru(II) to phenanthroline/pyridine-triazole-based MLCT emission, whereas cyanide fails to show a similar property due to a different redox process operational in the latter. The reduction of NDI in the presence of fluoride and cyanide in different polar solvents indicates that involvement of such deprotonated solvents in the electron transfer mechanism may not be operative in our present system. Low-temperature kinetic studies support the formation of a charge transfer associative transient species, which likely allows overcoming the thermodynamically uphill barrier for the direct electron transfer mechanism.

3.
Chem Commun (Camb) ; 55(35): 5127-5130, 2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-30973568

RESUMO

The solid state bright white light emission and mechanochromic behavior of 1-(1H-phenanthro[9,10-d]imidazol-2-yl)naphthalen-2-ol, 1H, are described. Further, 1H can be used as a highly sensitive ratiometric luminescence sensor for Al3+ and pyrophosphate in solution.

4.
Dalton Trans ; 47(19): 6819-6830, 2018 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-29725677

RESUMO

A quinoline-based C3-symmetric fluorescent probe (1), N,N',N''-((2,4,6-trimethylbenzene-1,3,5-triyl)tris(methylene))tris(1-(quinolin-2-yl)-N-(quinolin-2-ylmethyl)methanamine), has been developed which can selectively detect Zn2+ without the interference of Cd2+via significant enhancement in emission intensity (fluorescence "turn-ON") associated with distinct fluorescence colour changes and very low detection limits (35.60 × 10-9 M in acetonitrile and 29.45 × 10-8 M in 50% aqueous buffer (10 mM HEPES, pH = 7.4) acetonitrile media). Importantly, this sensor is operative with a broad pH window (pH 4-10). The sensing phenomenon has been duly studied through UV-vis, steady-state, and time-resolved fluorescence spectroscopic methods indicating 1 : 3 stoichiometric binding between 1 and Zn2+ which is further corroborated by 1H NMR studies. Density functional theoretical (DFT) calculations provide the optimized molecular geometry and properties of the zinc complex, 1[Zn(ClO4)]33+, which is proposed to be formed in acetonitrile. The results are in line with the solution-state experimental findings. The single crystal X-ray study provides the solid state structure of the trinuclear Zn2+ complex showing solubility in an aqueous buffer (10 mM HEPES, pH = 7.4). Finally, the resulting trinuclear Zn2+ complex has been utilized as a fluorescence "turn-OFF" sensor for the selective detection of pyrophosphate in a 70% aqueous buffer (10 mM HEPES, pH = 7.4) acetonitrile solvent with a nanomolar detection limit (45.37 × 10-9 M).

5.
Chemistry ; 22(50): 18051-18059, 2016 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-27805754

RESUMO

The selective phosphate-sensing property of a bis-heteroleptic RuII complex, 1[PF6 ]2 , which has a halogen-bonding iodotriazole unit, is demonstrated and is shown to be superior to its hydrogen-bonding analogue, 2[PF6 ]2 . Complex 1[PF6 ]2 , exploiting halogen-bonding interactions, shows enhanced phosphate recognition in both acetonitrile and aqueous acetonitrile compared with its hydrogen-bonding analogue, owing to considerable amplification of the RuII -center-based metal-to-ligand charge transfer (MLCT) emission response and luminescence lifetime. Detailed solution-state studies reveal a higher association constant, lower limit of detection, and greater change in lifetime for complex 1 in the presence of phosphates compared with its hydrogen-bonding analogue, complex 2. The 1 H NMR titration study with H2 PO4- ascertains that the binding of H2 PO4- occurs exclusively through halogen-bonding or hydrogen-bonding interactions in complexes 1[PF6 ]2 and 2[PF6 ]2 , respectively. Importantly, the single-crystal X-ray structure confirms the first ever report on metal-assisted second-sphere recognition of H2 PO4- and H2 P2 O72- with 1 through a solitary C-I⋅⋅⋅anion halogen-bonding interaction.

6.
Inorg Chem ; 55(18): 9212-20, 2016 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-27571218

RESUMO

An excited-state intramolecular proton transfer (ESIPT)-based highly sensitive ratiometric fluorescence sensor, 1H was developed for selective detection of aluminum (Al(3+)) in acetonitrile as well as in 90% aqueous system. Single-crystal X-ray diffraction analysis reveals almost planar and conjugated structure of 1H. Photophysical properties of the sensor as well as its selectivity toward Al(3+) are explored using UV-visible, steady-state, and time-resolved fluorescence spectroscopic studies. The bright cyan (λem = 445 nm) fluorescence of 1H in acetonitrile turns into deep blue (λem = 412 nm) with ∼2.3-fold enhancement in emission intensity, in the presence of parts per billion level Al(3+) (detection limit = 0.5 nM). Interestingly, the probe 1H exhibits increased selectivity toward Al(3+) in H2O/acetonitrile (9:1 v/v) solvent system with a change in fluorescence color from pale green to deep blue associated with ca. sixfold enhancement in emission intensity. Density functional theoretical (DFT) calculations provide the ground- and excited-state energy optimized structures and properties of the proposed aluminum complex [Al(1) (OH)]2(2+), which is in harmony with the solution-state experimental findings and also supports the occurrence of ESIPT process in 1H. The ESIPT mechanism was also ascertained by comparing the basic photophysical properties of 1H with a similar O-methylated analogue, 1'Me.

8.
Phytother Res ; 16(6): 590-2, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12237822

RESUMO

The glucose-lowering efficacy of a methanol extract of the stem bark of Ficus racemosa Linn. (MEBFR) (Family Moraceae) was evaluated both in normal and alloxan-induced diabetic rats. The MEBFR at the doses examined (200 and 400 mg/kg p.o.) exhibited significant hypoglycaemic activity in both experimental animal models when compared with the control group. The activity was also comparable to that of the effect produced by a standard antidiabetic agent, glibenclamide 10 mg/kg. The present investigation established pharmacological evidence to support the folklore claim that it is an antidiabetic agent.


Assuntos
Glicemia/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Ficus , Extratos Vegetais/farmacologia , Animais , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/mortalidade , Glibureto/farmacologia , Hipoglicemiantes/farmacologia , Dose Letal Mediana , Casca de Planta/química , Ratos , Ratos Wistar , Taxa de Sobrevida , Testes de Toxicidade
9.
Fitoterapia ; 73(1): 43-7, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11864763

RESUMO

The antidiarrhoeal activity of the methanol extract of the dried seeds of Strychnos potatorum (MESP) has been evaluated out in rats using different models (castor oil-induced diarrhoea, effects on gastrointestinal motility and on PGE(2)-induced gastric enteropooling. MESP (100, 200 and 400 mg/kg, p.o.) significantly (P<0.001) inhibited the frequency of defaecation and reduced the wetness of faecal droppings in castor oil-induced diarrhoea, decreased the propulsion of charcoal meal through the gastrointestinal tract, and also reduced the PGE(2)-induced enteropooling.


Assuntos
Antidiarreicos/farmacologia , Diarreia Infantil/tratamento farmacológico , Motilidade Gastrointestinal/efeitos dos fármacos , Loganiaceae , Fitoterapia , Extratos Vegetais/farmacologia , Animais , Antidiarreicos/administração & dosagem , Antidiarreicos/uso terapêutico , Dinoprostona/farmacologia , Relação Dose-Resposta a Droga , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Extratos Vegetais/administração & dosagem , Extratos Vegetais/uso terapêutico , Distribuição Aleatória , Ratos , Ratos Wistar , Sementes
10.
Anc Sci Life ; 21(3): 205-7, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22557056

RESUMO

The whole plant of Jussiaea suffruticosa Linn. Has been widely used in traditional medicine of India. Important bioactive molecules of the plant extract have been explored with modern phytochemical approaches and reported to consist of betulinic acid, quercetin and ß- sitosterol. Furthermore, the experimental data obtained from rational clinical studies indicated that the methanol extract of the whole plant has found to possess potent anti-HIV, anti-diabetic, anti-diarrheal, anti- inflammatory, anti-pyretic, diuretic and psychopharmacological activities in several animal models. This paper reveales the phytochemical and clinical importance of the plant extract.

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