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1.
J Dig Dis ; 24(6-7): 427-433, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37505932

RESUMO

OBJECTIVES: To systematically evaluate the patient and procedural risk factors for post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP) among patients receiving rectal indomethacin. METHODS: Data from a randomized controlled trial (RCT) of high-risk patients undergoing ERCP who received rectal indomethacin with or without topical epinephrine was evaluated. PEP was defined based on the consensus criteria. Pancreatic stenting was excluded to avoid confounding results with the role of epinephrine spray. Multivariable logistic regression analysis was used to identify patient and procedural risk factors for PEP. RESULTS: Among 960 patients enrolled in the RCT, the PEP incidence was 6.4%. An increased risk of PEP was seen with age <50 years and female gender (odds ratio [OR] 2.40, 95% confidence interval [CI] 1.35-4.26), malignant biliary stricture(s) (OR 3.51, 95% CI 1.52-8.10), >2 guidewire passes into the pancreatic duct (PD) (OR 2.84, 95% CI 1.43-5.64), and pancreatic brush cytology (OR 6.37, 95% CI 1.10-36.90), whereas a decreased risk of PEP was seen with contrast- over guidewire-assisted cannulation (OR 0.14, 95% CI 0.02-0.99) and the use of lactated Ringer's (LR) over other fluid types (OR 0.52, 95% CI 0.27-0.98). There was a significant trend between the number of guidewire passes into the PD and PEP risk (P = 0.002). CONCLUSIONS: More than two guidewire passes into the PD and pancreatic brush cytology increased while the use of LR decreased the risk of PEP among high-risk patients receiving rectal indomethacin. Pancreatic stent placement and/or LR should be considered in patients with >2 guidewire passes into the PD.


Assuntos
Colangiopancreatografia Retrógrada Endoscópica , Pancreatite , Feminino , Humanos , Pessoa de Meia-Idade , Cateterismo/métodos , Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Colangiopancreatografia Retrógrada Endoscópica/métodos , Epinefrina , Indometacina/uso terapêutico , Ductos Pancreáticos , Pancreatite/epidemiologia , Pancreatite/etiologia , Pancreatite/prevenção & controle , Fatores de Risco , Masculino , Adulto
2.
Antibiotics (Basel) ; 11(3)2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35326823

RESUMO

Staphylococcus haemolyticus has emerged to be a frequently encountered late-onset sepsis pathogen among newborn infants. Critical care of neonates involves substantial usage of antibiotics and these pathogens are often exposed to sub-optimal doses of antibiotics which can augment maintenance of selection determinants and a range of physiological effects, prime among them being biofilm formation. Therefore, in this study, the outcome of a sub-inhibitory dosage of a commonly prescribed third-generation antibiotic, cefotaxime (CTX), on multidrug resistant (MDR) S. haemolyticus, was investigated. A total of 19 CTX-resistant, MDR and 5 CTX-susceptible strains isolated from neonates were included. Biofilm-forming abilities of S. haemolyticus isolates in the presence of sub-optimal CTX (30 µg/mL) were determined by crystal violet assays and extracellular DNA (eDNA) quantitation. CTX was found to significantly enhance biofilm production among the non-susceptible isolates (p-valueWilcoxintest­0.000008) with an increase in eDNA levels (p-valueWilcoxintest­0.000004). Further, in the absence of antibiotic selection in vitro, populations of MDR isolates, JNM56C1 and JNM60C2 remained antibiotic non-susceptible after >500 generations of growth. These findings demonstrate that sub-optimal concentration of CTX induces biofilm formation and short-term non-exposure to antibiotics does not alter non-susceptibility among S. haemolyticus isolates under the tested conditions.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 247: 119079, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33120118

RESUMO

Recently, a considerable amount of research is being directed towards study of graphene oxide (GO) and its reduced form (RGO) since their exposed functional groups make them better candidates in nanobiotechnolgy. In order to assess their biocompatibility, the nature of interactions between Human Hemoglobin (HHb) and GO/RGO are monitored since a comparative spectroscopic approach towards understanding their nature of interactions has not been investigated previously. UV-vis spectroscopy reveals hyperchromicity for HHb-GO system and hypochromicity for HHb-RGO system in the region of absorption of tryptophan/tyrosine residues. Notably, although steady-state fluorescence static quenching of HHb for GO and enhancement of fluorescence for RGO is noticed, but average fluorescence-lifetime is remaining unchanged in presence of GO/RGO. Calorimetric data illustrates three-site and five-site binding model to be the best-fit model for GO and RGO respectively. Also, synchronous fluorescence quenching corresponding to alterations in microenvironment of tryptophan/ tyrosine residues is observed only in presence of GO. Likewise FTIR spectroscopy elucidates involvement of both amide I and amide II bond of HHb backbone through H-bonding interaction only for GO. Furthermore RLS spectra demonstrate an increase and a decrease in signal for GO and RGO respectively. Surprisingly, secondary structure of HHb is maintained upon interaction with both GO/RGO, as revealed by CD spectroscopy, thus supporting their potential application in biological microenvironment. Thus it appears that the spectroscopic properties of HHb upon interaction with GO is altered upon its reduction to RGO. Furthermore the role of HHb as good candidate for bimolecular interaction has been highlighted.


Assuntos
Grafite , Pontos Quânticos , Carbono , Hemoglobinas , Humanos , Óxidos
4.
Artigo em Inglês | MEDLINE | ID: mdl-32033408

RESUMO

Indiscriminate use of antibiotics has resulted in a catastrophic increase in the levels of antibiotic resistance in India. Hospitals treat critical bacterial infections and thus can serve as reservoirs of multidrug resistant (MDR) bacteria. Hence, this study was conducted to gauge the prevalence patterns of MDR bacteria in hospital wastewater. Water samples collected from 11 hospitals and 4 environmental sources belonging to 5 most-densely populated districts of West Bengal, India were grown on MacConkey and Eosin Methylene Blue agar. A total of 84 (hospital-associated = 70, environmental water sources = 14) isolates were characterized. The predominant species found in water from hospital-associated areas (HAA) were Acinetobacter baumannii (22.9%), Escherichia coli (28.6 %), and Klebsiella pneumoniae (25.7%). Greater than 75% of the HAA isolates were found to be mcr-1 gene negative and colistinresistant. Meropenem non-susceptibility was also high among the HAA isolates at 58.6%, with the presence of the carbapenemase gene and blaNDM in 67.1% of the non-susceptible isolates. Among the three predominant species, significantly higher numbers of E. coli isolates were found to be non-susceptible to meropenem ((80%), p-value = 0.00432) and amikacin (AK (90%), p-value = 0.00037). This study provides evidence for the presence of high numbers of colistin-resistant and carbapenem-hydrolyzing Proteobacteriain hospital wastewater.


Assuntos
Antibacterianos/efeitos adversos , Carbapenêmicos/toxicidade , Colistina/efeitos adversos , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Proteobactérias/efeitos dos fármacos , Proteobactérias/isolamento & purificação , Águas Residuárias/toxicidade , Humanos , Testes de Sensibilidade Microbiana , Prevalência , Águas Residuárias/microbiologia
5.
Phys Rev Lett ; 125(25): 251801, 2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33416371

RESUMO

Neutrinos in a core-collapse supernova can undergo fast flavor conversions with a possible impact on the explosion mechanism and nucleosynthesis. We perform the first nonlinear simulations of fast conversions in the presence of three neutrino flavors. The recent supernova simulations with muon production call for such an analysis, as they relax the standard ν_{µ,τ}=ν[over ¯]_{µ,τ} (two-flavor) assumption. Our results show the significance of muon and tau lepton number angular distributions, together with the traditional electron lepton number ones. Indeed, our three-flavor results are potentially very different from two-flavor ones. These results strengthen the need to further investigate the occurrence of fast conversions in supernova simulation data, including the degeneracy breaking of mu and tau neutrinos.

6.
Antibiotics (Basel) ; 8(4)2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31600988

RESUMO

: Carbapenem resistant Klebsiella pneumoniae has been highlighted to be a critical pathogen by the World Health Organization. The objectives of this study were to assess the efficacy of lactic acid (LA) against planktonic cells and biofilms formed by carbapenem-hydrolyzing K. pneumoniae isolates obtained from the nares of preterm neonates. Time-kill assays with graded percentages of (v/v) LA in water were initially carried out against planktonic cells of a meropenem (MRP)-resistant K. pneumoniae isolate, JNM11.C4. The efficacy parameters such as optimal incubation time and minimum inhibitory concentration were determined by comparing colony-forming unit counts (log(10)CFU). Scanning electron microscopy was used to visualize cell damage. Likewise, JNM11.C4 biofilms were treated with graded series of (v/v) LA. Six carbapenem-hydrolyzing isolates were next used to validate the results. A reduction of 3.6 ± 0.6 log(10) CFU/mL in JNM11.C4 planktonic cells and >3 ± 0.03log(10) CFU/mL in biofilm-forming cells were observed using 0.225% and 2% LA, respectively, after three hours. Similar decreases in viable cell-counts were observed both in the case of planktonic (˃3.6 ± 0.3log(10) CFU/mL) and biofilm-forming cells (3.8 ± 0.3log(10) CFU/mL) across all the six clinical isolates. These results indicate that LA is an effective antimicrobial against planktonic carbapenem-hydrolyzing K. pneumoniae cells and biofilms.

7.
Spectrochim Acta A Mol Biomol Spectrosc ; 215: 313-326, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30851689

RESUMO

CQDs have emerged with outstanding properties as a star member of carbon nanomaterial family and in order to reveal its wide-range of application in biological microenvironment the interactions between human hemoglobin (HHb) and CQD and also with ethylenediamine-functionalized CQD (NCQD) are assessed using several techniques. Firstly, UV-vis absorption spectra of HHb reveal hyperchromic effect in the region of absorbance of tryptophan and tyrosine residues and also hypochromicity of Soret band in presence of CQD and NCQD. Interestingly, steady-state fluorescence spectroscopy reveal distinct fluorescence enhancement of HHb with significant red shift thereby indicating exposures of tryptophan and tyrosine residues to a more hydrophilic environment. However synchronous fluorescence spectra reveal that the microenvironment of tryptophan and tyrosine residues is altered in opposite manner, i.e. exposure of tryptophan residues to a more hydrophilic environment and the tyrosine residues to a more hydrophobic environment. Moreover the fluorescence enhancement is observed to be accompanied by increase in average fluorescence-lifetime and decrease in steady-state anisotropy thus signifying a decrease in restriction of rotational motion. Furthermore tryptophan residues within HHb appear to interact more with CQD compared to NCQD. Thermodynamic parameters as revealed by Isothermal Titration Calorimetry (ITC) demonstrate that electrostatic, hydrogen bonding and hydrophobic interactions are the predominant modes of interactions in presence of CQD. Whereas hydrophobic and hydrogen bonding interactions are the major interacting forces in presence of NCQD with five-site sequential binding as best-fit model in both the cases. Such interactions also appear to be associated with an increase in aggregation of HHb as evident from the measurements by atomic force microscopy (AFM) and dynamic light scattering (DLS) study. Although FT-IR spectra display alteration of amide I band, but the overall secondary structure of HHb seems to be nearly retained even in presence of CQDs, as evident in the CD spectra. These observations thus highlight the potential biomedical application of CQDs in biological microenvironment of human especially as drug-delivery system. Also bimolecular interaction of HHb as a model protein with other nanoparticles at the nano bio-interface has been outlined.


Assuntos
Hemoglobinas/análise , Hemoglobinas/química , Pontos Quânticos/química , Espectrometria de Fluorescência/métodos , Carbono/química , Humanos , Modelos Moleculares , Termodinâmica
9.
J Photochem Photobiol B ; 178: 355-366, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29182925

RESUMO

The nature of interactions between heme protein human hemoglobin (HHb) and gold nanoparticles of two different morphologies that is GNP (spherical) and GNS (star-shaped) have been investigated by using UV-vis absorption, steady state fluorescence, synchronous fluorescence, resonance light scattering (RLS), time resolved fluorescence, FT-IR, and circular dichroism (CD) techniques under physiological condition of pH ~7 at ambient and different temperatures. Analysis of the steady state fluorescence quenching of HHb in aqueous solution in the presence of GNP and GNS suggests that the nature of the quenching is of static type. The static nature of the quenching is also confirmed from time resolved data. The static type of quenching also indicates the possibility of formation of ground state complex for both HHb-GNP and HHb-GNS systems. From the measurements of Stern-Volmer (SV) constants KSV and binding constants, KA and number of binding sites it appears that HHb forms stronger binding with GNP relative to GNS. Analysis of the thermodynamic parameters indicates that the formation of HHb-GNP and HHb-GNS complexes are spontaneous molecular interaction processes (∆G<0). In both cases hydrogen bonding and van der Waals interactions play a dominant role (∆H<0, ∆S<0). Synchronous fluorescence spectroscopy further reveals that the ground state complex formations of HHb-GNP and HHb-GNS preferably occur by binding with the amino acid tyrosine through hydrogen bonding interactions. Moreover the α-helicity contents of the proteins as obtained from the circular dichroism (CD) spectra appears to be marginally reduced by increasing concentrations of GNP and GNS and the α-helical structures of HHb retain its identity as native secondary structure in spite of complex formations with GNP or GNS. These findings demonstrate the efficiency of biomedical applications of GNP and GNS nanoparticles as well as in elucidating their mechanisms of action as drugs or drug delivery systems in human.


Assuntos
Ouro/química , Hemoglobinas/química , Nanopartículas Metálicas/química , Dicroísmo Circular , Hemoglobinas/metabolismo , Humanos , Ligação de Hidrogênio , Concentração de Íons de Hidrogênio , Estrutura Secundária de Proteína , Espectrometria de Fluorescência , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Temperatura , Termodinâmica
10.
Photochem Photobiol Sci ; 13(12): 1719-29, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25314902

RESUMO

Moderate intensity SMF have been shown to act as a controller of the protic potential in the coherent milieu of the thylakoid membranes. SMF of the order of 60-500 mT induces memory-like effect in photosystem I (PSI, P723) emission with a correlated oscillation of photosystem II (PSII, P689) fluorescence emission at a temperature of 77 K. The observed magnetic perturbation that affects the thylakoid photon capture circuitry was also found to be associated with the bio-energetic machinery of the thylakoid membranes. At normal pH, SMF causes an enhancement of PSI fluorescence emission intensity (P723/P689 > 1), followed by a slow relaxation on the removal of SMF. The enhancement of the PSI fluorescence intensity also occurs under no-field condition, if either the pH of the medium is lowered, or protonophores, such as carbonyl cyanide chlorophenylhydrazine or nigericin are added (P723/P689≥ 2). If SMF was applied under such a low pH condition or in the presence of protonophore, a reverse effect, particularly, a reduction of the enhanced PSI emission was observed. Because SMF is essentially equivalent to a spin perturbation, the observed effects can be explained in terms of spin re-organization, illustrating a memory effect via membrane re-alignment and assembly. The mimicry of conventional uncouplers by SMF is also notable; the essential difference being the reversibility and manoeuvrability of the latter (SMF). Finally, the effect implies numerous possibilities of externally regulating the photon capture and proton circulation in the thylakoid membranes using controlled SMF.


Assuntos
Campos Magnéticos , Complexo de Proteína do Fotossistema I/química , Complexo de Proteína do Fotossistema II/química , Arachis , Fluorescência , Concentração de Íons de Hidrogênio , Cinética , Nigericina/química , Permeabilidade , Prótons , Análise Espectral , Temperatura , Tilacoides/química
11.
J Bioenerg Biomembr ; 46(1): 71-82, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24214386

RESUMO

Energy distribution between photosystems (PSI & PSII) under prolonged and continuous white light irradiance was assessed by monitoring the progress of their fluorescence emission (FPSI/FPSII) at 77 K. Our observations indicate FPSI/FPSII to oscillate with the progress of irradiance treatments at all intensities tested (100, 200, 500, and 800 µE m(-2) S(-1)). The amplitude of the oscillation increased with the progress, whereas the periodicity of the oscillation increased with the intensity of the incident irradiance. Spectral analysis indicated fluctuation of FPSI to be the major determinant of the observed oscillation. The first rise and fall of FPSI/FPSII overlapped with phosphorylation and dephosphorylation of LHCII, but oscillation of FPSI/FPSII continued for several cycles without any further phosphorylation of LHCII. Moreover, in presence of DCMU where linear electron flow (LEF) is suppressed and LHCII phosphorylation is completely abolished, the oscillation of FPSI/FPSII was not abolished. These data indicated that LHCII phosphorylation was not essential for the observed oscillation of energy distribution between the photosystems. In contrast, in the presence of inhibitors of cyclic electron flow (CEF) like Antimycin A (AA) and rotenone, the oscillation of FPSI/FPSII was either abolished or severely dampened. Additionally, the oscillation was also abolished in presence of uncouplers like NH4Cl and nigericin that cancels the trans-thylakoid ∆pH. Thus, trans-thylakoid ∆pH, generated through CEF, appear to be an important determinant of oscillation of FPSI/FPSII in isolated thylakoids. The phenomenon of oscillation could be associated with a CEF mediated chromatic adaptation of PSI in presence of excess irradiance.


Assuntos
Arachis/metabolismo , Arachis/efeitos da radiação , Complexo de Proteína do Fotossistema I/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo , Tilacoides/metabolismo , Elétrons , Concentração de Íons de Hidrogênio , Luz , Fosforilação , Folhas de Planta/metabolismo , Folhas de Planta/efeitos da radiação
12.
J Clin Anesth ; 23(3): 202-6, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21489768

RESUMO

STUDY OBJECTIVE: To report the use of spinal anesthesia in stable eclamptic patients. DESIGN: Prospective case series. SETTING: Emergency operating room of a metropolitan hospital. PATIENTS: 12 "stable" eclamptic parturients. INTERVENTIONS: Subarachnoid block was instituted with hyperbaric 0.5% bupivacaine 1.7 mL with fentanyl 25 µg. MEASUREMENTS: Intraoperative maternal hypotension, episodes of convulsion, the need to convert to general anesthesia, and Apgar scores at 1 and 5 minutes were recorded. MAIN RESULTS: Only one of the 12 parturients had an episode of hypotension (treated by intravenous ephedrine), while no patient had a convulsion over the 48 hours after delivery. The sensory level achieved was T5-T6 and none of the cases was converted to general anesthesia. Median Apgar scores at 1 and 5 minutes were 8 and 9, respectively. CONCLUSION: Spinal anesthesia avoided the known risks of general anesthesia and was not associated with any major complications.


Assuntos
Anestesia Obstétrica , Raquianestesia , Cesárea , Eclampsia/fisiopatologia , Adulto , Índice de Apgar , Feminino , Humanos , Recém-Nascido , Gravidez , Estudos Prospectivos
13.
Indian J Gastroenterol ; 30(1): 33-7, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21424697

RESUMO

INTRODUCTION: The past decade has witnessed a global rise in the prevalence of peptic ulcer disease which is unrelated to non-steroidal anti-inflammatory drugs (NSAIDs) or Helicobacter pylori infection. Although initially recognized in the West, this disease is being increasingly recognized in the Asian population. The higher risk of bleeding and ulcer recurrence in this subgroup of patients highlights the clinical importance of analyzing the changing trends of peptic ulcer disease in developing countries. AIMS: To assess the proportion of non-NSAID, non-H. pylori peptic ulcer disease in an Indian cohort of patients with peptic ulcer disease managed at a tertiary care center; and to compare the gastric and duodenal ulcer subgroups in these patients. METHODS: Patients diagnosed with peptic ulcer disease were screened for a history of NSAID use and those with a negative history were tested for H. pylori using a combination of rapid urease test (RUT) and (14)C-urea breath test (UBT). Only those cases which tested negative for both the tests were considered 'H. pylori-negative'. Serum gastrin was measured in all patients included in the study. RESULTS: Seventy-four gastric ulcer (GU) and 54 duodenal ulcer (DU) patients with no history of NSAID use were enrolled. Of these, 36 GU (45.9%) and 16 DU (29.6%) patients were H. pylori-negative. The proportion of non-NSAID non-H. pylori gastric ulcers was significantly higher than duodenal ulcers (p < 0.05). However, patients who tested negative for H. pylori did not differ significantly from those who tested positive with regard to age, gender, serum gastrin level, and presence of risk factors, like smoking and alcoholism. CONCLUSION: The current study indicates existence of high proportion of non-NSAID, non-H. pylori peptic ulcer disease in Indian patients.


Assuntos
Úlcera Péptica/etiologia , Adolescente , Adulto , Idoso , Anti-Inflamatórios não Esteroides , Estudos Transversais , Feminino , Infecções por Helicobacter/diagnóstico , Helicobacter pylori/isolamento & purificação , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Úlcera Péptica/epidemiologia , Estudos Prospectivos , Fatores de Risco , Ureia/análise , Urease/sangue , Adulto Jovem
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