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1.
J Fluoresc ; 29(1): 27-40, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30374939

RESUMO

A novel luminescent hydrazone ligand was synthesized via 1:1 condensation reaction of 9-anthracene aldehyde and 2-hydrazinobenzoic acid followed by its characterization with the help of absorption, emission, FTIR, NMR and mass studies. It was investigated as a reversible, ratiometric and turn-on luminescent chemosensor for Cu2+ in aqueous environment. The receptor shows a prominent color change in presence of Cu2+ from yellow to reddish brown in DMSO-H2O (2:1) medium. Upon addition of Cu2+, a remarkable increment in emission intensity (Φ = 0.091, 11 fold) was observed probably due to intra-ligand charge transfer transition (ILCT). Interestingly, this sensor is capable to extract Cu2+ selectively from aqueous mixture of metal ions using dichloromethane solvent with the increased extraction efficiency from 85% (L:Cu2+, 1:1) to 95% (L:Cu2+, 2:1) in the pH range of 6.5-10.0. The extraction behavior of Cu2+ was monitored with the help of UV-Vis spectroscopy and a readily-usable smartphone to capture the RGB data which may be helpful as a field based analysis tool. In presence of Cu2+ (1.0 × 10-5 M), no significant interference was observed after addition of 5-fold excess of other metal ions (Zn2+, Cd2+, Co2+, Fe2+, Fe3+, Ni2+, Hg2+, Sn2+, Al3+, Cr3+, Mn2+) in DMSO-H2O (2:1) medium. Moreover, the ligand was regenerated (> 98%) by adjusting the pH upto 4 cycles and showed a good recyclability and reusability which might be helpful to extract Cu2+ efficiently from aqueous medium.

2.
J Fluoresc ; 27(5): 1567-1572, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27878520

RESUMO

A new coumarin based chemosensor has been developed for selective fluorescent recognition of Cu2+ in MeOH/H2O (4:1, v/v at pH = 7.2 aqueous solution) medium with 1:1 binding stoichiometry. The in-situ prepared Cu2+ complex displays high selectivity towards CN- via Cu2+ displacement approach with detection limit in the micro molar range. Moreover, in presence of Cu2+, the receptor exhibits reversible emission change with EDTA and thus offers an interesting property of molecular 'IMPLICATION' logic gate with Cu2+ and EDTA as chemical inputs.

3.
J Fluoresc ; 26(3): 1021-8, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27034064

RESUMO

A new Schiff-base, HL luminescent chemosensor of 1-amino pyrene and 8-hydroxy quinoline-2-carboxaldehyde was synthesized which demonstrates selective fluorimetric detection of Fe(3+) in aqueous medium with detection limit of 2.52 × 10(-8) M. The receptor shows selective 'turn-on' response towards Fe(3+) over other metal ions. This gradual 'turn-on' fluorescence response for Fe(3+) may be induced via CHEF (chelation-enhanced fluorescence) through close proximity of pyrene rings. The stoichiometry and binding property of HL with Fe(3+) was examined by emission studies. In presence of Fe(3+), HL also exhibits reversible change in emission pattern with EDTA and thus offers an interesting property of molecular 'INHIBIT' logic gate with Fe(3+) and EDTA as chemical inputs.

4.
Soft Matter ; 11(30): 6152-61, 2015 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-26143752

RESUMO

Self-healing oxime-functional hydrogels have been developed that undergo a reversible gel-to-sol transition via oxime exchange under acidic conditions. Keto-functional copolymers were prepared by conventional radical polymerization of N,N-dimethylacrylamide (DMA) and diacetone acrylamide (DAA). The resulting water soluble copolymers (P(DMA-stat-DAA)) were chemically crosslinked with difunctional alkoxyamines to obtain hydrogels via oxime formation. Gel-to-sol transitions were induced by the addition of excess monofunctional alkoxyamines to promote competitive oxime exchange under acidic conditions at 25 °C. The hydrogel could autonomously heal after it was damaged due to the dynamic nature of the oxime crosslinks. In addition to their chemo-responsive behavior, the P(DMA-stat-DAA) copolymers exhibit cloud points which vary with the DAA content in the copolymers. This thermo-responsive behavior of the P(DMA-stat-DAA) was utilized to form physical hydrogels above their cloud point. Therefore, these materials can either form dynamic-covalent or physically-crosslinked gels, both of which demonstrate reversible gelation behavior.


Assuntos
Materiais Biocompatíveis/química , Reagentes de Ligações Cruzadas/química , Hidrogéis/química , Oximas/química , Acrilamida/síntese química , Acrilamida/química , Acrilamidas/síntese química , Acrilamidas/química , Materiais Biocompatíveis/síntese química , Hidrogéis/síntese química , Oximas/síntese química , Transição de Fase , Polietilenoglicóis , Polímeros/síntese química , Polímeros/química , Temperatura , Água/química
5.
J Fluoresc ; 25(5): 1461-7, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26293480

RESUMO

A new aromatic hydrazone based on pyrene-1-aldehyde was synthesized and characterized by (1)H NMR and mass spectrometric analyses. The sensing properties of the hydrazone were studied by absorption and fluorescence studies in the aprotic solvent DMSO. It was capable of visual and fluorescent detection of fluoride over competitive ions (Cl(-), Br(-), H2PO4 (-), AcO(-)). Moreover, the in-situ prepared iron(III) complex of the hydrazone was investigated as a turn off fluorescent fluoride sensor in aqueous medium by displacement mechanism.

6.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 11): 382-4, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25484752

RESUMO

In the title compound, C12H13N2 (+)·Cl(-), the chloride salt of 1,1'-di-phenyl-hydrazine, the phenyl rings are inclined to one another by 78.63 (17)°. The N-(+)NH3 bond lengths is 1.445 (3) Å, and the N-Cphen-yl bond lengths are 1.435 (3) and 1.447 (4) Å. In the crystal, mol-ecules are linked via N-H⋯Cl hydrogen bonds, forming chains along [10-1], which enclose two adjacent R (4) 2(6) ring motifs. The chains are reinforced by C-H⋯Cl hydrogen bonds.

7.
Anal Sci ; 39(9): 1551-1560, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37244980

RESUMO

The sensitive, non-destructive constant wavelength (CW) and constant energy (CE) SFS techniques have been used for the simultaneous determination of 1-amino pyrene (AP) and 1-napthyl amine (NA) in their mixtures without prior separation via optimization of different experimental conditions (ΔλCW 70.0 nm, ΔνCE 4000.0 cm-1, scan rate 240.0 nm/min, 25.0 °C, methanol). Amplitude-concentration plots have been linear for 1-amino pyrene, AP (0.01-0.1 mg/L) and 1-napthyl amine, NA (0.1-1.0 mg/L). In aqueous methanolic binary mixtures, the mean recoveries (RSD, LOD and LOQ) of AP were found to be 100.09% (0.053, 0.008 mg/L and 0.034 mg/L) for emission, 100.11% (0.141, 0.008 mg/L, 0.034 mg/L) for CWSFS, 100.05% (0.109, 0.007 mg/L and 0.032 mg/L) for first derivative CWSFS, 100.00% (0.148, 0.007 mg/L and 0.031 mg/L) for CESFS, 99.99% (0.109, 0.008 mg/L and 0.035 mg/L) for first derivative CESFS modes respectively. Additionally, for NA the mean recoveries (RSD, LOD and LOQ) were 100.29% (0.360, 0.046 mg/L and 0.204 mg/L) for emission, 100.06% (0.089, 0.098 mg/L, 0.436 mg/L) for CWSFS, 100.09% (0.144, 0.065 mg/L and 0.288 mg/L) for first derivative CWSFS, 100.05% (0.178, 0.077 mg/L and 0.339 mg/L) for CESFS, 100.03% (0.181, 0.082 mg/L and 0.364 mg/L) for first derivative CESFS modes respectively. Considering their safety and greenness, these methods might be considered as green tools using analytical eco-scale approaches (eco-scale score 88.0).

8.
J Pharm Bioallied Sci ; 13(Suppl 2): S1381-S1385, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35017993

RESUMO

BACKGROUND: Triple test was a breakthrough in the initial screening of breast cancer due to its high sensitivity, but it has few limitations. To overcome those limitations, we developed a novel quadruple score which included physical examination, ultrasound, mammography, and fine-needle aspiration cytology (FNAC). AIM: The aim of this study was to test the sensitivity, specificity, negative predictive value (NPV), and positive predictive value of a novel quadruple score for the initial screening of breast cancer. METHODOLOGY: This retrospective study was conducted on 320 patients having breast lump to the Breast Cancer Outpatient Department of AIIMS, Bhopal. The physical examination findings, breast sonography findings, mammography, and FNAC findings were recorded in the set pro forma, these were later analyzed, and a cumulative scoring was done categorizing patients in the benign, dubious, and malignant category according to the QTS score. These findings were then validated and compared by histopathology. RESULTS: Statistical results show a positive covariance σ suggesting the positive relation between them; also, the correlation coefficient was 0.9996 suggesting a strong linear correlation. On comparing the accuracy of all four variables as physical examination, USG, mammography and FNAC individually and QTS, the accuracy of QTS was highest i.e 99.44%. CONCLUSION: QTS is accurate and reliable diagnostic approach for evaluation of breast lumps. By using the quadruple scoring system, management of palpable breast lump will become more streamlined, providing a platform for managing discordant results, which can be followed universally.

9.
Spectrochim Acta A Mol Biomol Spectrosc ; 228: 117837, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31784221

RESUMO

A well designed, new pyrene based small molecule (L) was synthesized from 1:1 condensation reaction of 1-aminopyrene and 6-(1,3-benzodioxal-5-yl)-2-pyridine carboxaldehyde which was characterized by absorption, emission spectrometry, FTIR, NMR and mass studies. Interestingly the UV-vis and fluorescence spectroscopic studies revealed that the ligand (L) works as a dual turn-on luminescent chemosensor for chromium(III) (Cr3+) and aluminium(III) (Al3+) in aqueous environment which were further supported by DFT and TDDFT studies. L shows a significant colour change from pale yellow to reddish yellow with a detection limit of ~10-9 M in the presence of Cr3+ and Al3+ whereas there were no noteworthy changes in the presence of other monovalent and divalent metal ions. The molecular signaling in the presence of Cr3+, Al3+, Fe3+ and EDTA was compared with advanced level combinational INHIBIT gate based on 4 input logic gates. Herein, first derivative constant wavelength synchronous fluorescence spectroscopy (1st DCWSFS) was applied for the determination of Cr3+, Al3+ ion concentrations in a mixture via increment of spectral resolution of the respective overlapping peaks. 1st DCWSFS is reported to be used in pharmaceuticals but very few works have been done for determination of metal ion concentration in environmental sample without prior separation. The individual Cr3+and Al3+ ion concentrations in a mixture were determined through liquid-liquid extraction process and the efficiencies were compared with 1st derivative SFS method. It was observed that 1st derivative SFS process is more efficient than conventional liquid-liquid extraction process. Therefore, 1st DCWSFS method using sensor L might be useful as a diagnostic tool for detection of individual metal ion concentrations (Cr3+ and Al3+) from a mixture which will be cost-effective, time saving and more precise.

10.
J Food Sci ; 82(10): 2313-2320, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28892153

RESUMO

This study investigated the efficacy of ultra-high pressure homogenization (UHPH) in the presence or absence of added hydrocolloids for enhancing a range of physic-chemical properties of soymilk-which are important for extending shelf-life. Soymilk preparations containing different concentrations (0.01%, 0.02%, and 0.05%, w/v) of 2 different hydrocolloids (κ-carrageenan, κ-C, and gum Arabic, GA) were subjected to 3 different levels of UHPH (70, 140, and 210 MPa) and stored in sterilized containers at 4 °C. Emulsion properties of the soymilk preparations were analyzed over a period of 5 weeks. The results showed that soymilk with 0.05% κ-C had markedly improved storage properties, evident by significantly (P < 0.05) enhanced surface energy and absolute ζ potential values compared to the unhomogenized soymilk with no hydrocolloid (16% and 39% augmentations, respectively) at the 1st week of storage. This trend continued throughout the entire period of study. The soymilk containing 0.05% κ-C also exhibited significantly (P < 0.05) lower (60%) mean globular particle size at the initial week compared to the latter ones and maintained the trend throughout the 3rd week of storage. The study can potentially lead to a considerable economic benefit to the soymilk industry by providing valuable information to extend shelf-life of soymilk. PRACTICAL APPLICATION: Soymilk is one of the most important soy products, and as a beverage, it is rapidly gaining popularity in the Western markets. However, it tends to form precipitates during storage to affect quality of the product. This study used a 2-prong approach of ultra-high pressure homogenization and addition of hydrocolloids to prevent aggregation of soymilk particles and the retention of antioxidant capacity. The results showed enhancement of the quality of soymilk during storage. The techniques developed can be adopted by the food industry.


Assuntos
Coloides/química , Aditivos Alimentares/análise , Manipulação de Alimentos/métodos , Leite de Soja/química , Carragenina/análise , Emulsões/análise , Manipulação de Alimentos/instrumentação , Armazenamento de Alimentos , Goma Arábica/análise , Tamanho da Partícula , Pressão
11.
Eur J Obstet Gynecol Reprod Biol ; 129(2): 145-9, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16517044

RESUMO

OBJECTIVES: We sought to validate and measure the electrical impedance of the uterine cervix in non-pregnant and pregnant women by spectroscopy. STUDY DESIGN: Cervical stromal impedance (CSI) was measured in 50 non-pregnant, 20 1st, 20 2nd and 50 3rd trimester pregnant women. The technique was also validated by comparing in vivo data to a finite element (FE) model of cervical tissue. RESULTS: CSI agreed well with the FE model and was highly reproducible in all study groups. Mean (S.E.) CSI at 4-819 kHz was higher in pregnant (2.78 +/- 0.09 Omega m) compared to non-pregnant (2.38 +/- 0.07, p < 0.01) women, and in the 3rd trimester (3.08 +/- 0.13) compared to non-pregnant (p < 0.01), 1st trimester (2.42 +/- 0.12, p < 0.001) and 2nd trimester (2.20 +/- 0.05, p < 0.001) pregnant women. CONCLUSION: Measurement of CSI provides a non-invasive method of assessing cervical tissue characteristics. Cervical extracellular matrix synthesis and leukocyte infiltration may account for the increased tissue impedance noted in the 3rd trimester.


Assuntos
Maturidade Cervical/fisiologia , Colo do Útero/fisiologia , Análise de Elementos Finitos , Adolescente , Adulto , Colo do Útero/anatomia & histologia , Colágeno/fisiologia , Impedância Elétrica , Feminino , Humanos , Pessoa de Meia-Idade , Gravidez , Análise Espectral/métodos
12.
J Microbiol Immunol Infect ; 47(4): 354-7, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22743593

RESUMO

Amoebiasis of the uterine cervix is an extremely rare entity, and presentation as fibroid uterus has not been reported, to the best of our knowledge in our extensive search of the English literature. It can clinically simulate cervical malignancy by virtue of surface papillomatous and overall ulcerated and necrotic appearance. We present a case of amoebic infection of the cervix in a 45-year-old female which was suspected to be a posterior wall fibroid with degeneration until a histopathological examination of the surgical specimen revealed the presence of Entamoeba histolytica trophozoites. The patient recovered after surgery and antiamoebic therapy.


Assuntos
Amebíase/diagnóstico , Leiomioma/diagnóstico , Cervicite Uterina/diagnóstico , Cervicite Uterina/parasitologia , Amebíase/tratamento farmacológico , Amebíase/cirurgia , Diagnóstico Diferencial , Entamoeba histolytica , Feminino , Humanos , Pessoa de Meia-Idade , Cervicite Uterina/tratamento farmacológico , Cervicite Uterina/cirurgia
13.
J Nat Sci Biol Med ; 5(2): 425-8, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25097428

RESUMO

INTRODUCTION: Abruptio placentae (AP) which is a major cause of maternal morbidity and perinatal mortality globally is of serious concern in the developing world. We retrospectively analyzed the AP cases and evaluated its impact on fetal and maternal outcomes. MATERIALS AND METHODS: The present study was undertaken from September 2007-August 2009 at a tertiary care center attached to medical college; patients of AP were selected from all cases with minimum of 28 weeks of gestation, presenting with antepartum hemorrhage. Patients underwent complete obstetrical investigations and were managed according to maternal and fetal condition. RESULTS: 4.4% incidence rate of AP was documented accounting for 318 cases during the study period. Most of cases were unbooked, with an average age of 34.5 years (range, 18-44) and nearly two-third of the patients were from lower socioeconomic class. Anemia was observed in 96% of patients, with 3.5 and 68% incidence of maternal and fetal mortality, respectively. CONCLUSION: We observed a higher than expected frequency of AP and neonatal mortality in our study population, which is of major concern. We envisage need for mass information regarding the importance of antenatal maternal care and improvement in nutritional status, which may reduce the frequency of maternal and fetal morbidity and mortality associated with AP.

14.
Int J Prev Med ; 4(5): 603-6, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23930173

RESUMO

Ludwig's angina is an infectious process involving submandibular, sublingual, and submental spaces that can rapidly progress to hemodynamic instability and airway obstruction. A 38-year-old unbooked multipara of low socioeconomic status with a poor oral and dental hygiene presented with bilateral submandibular cellulitis and intrauterine fetal demise. She delivered vaginally, and subsequently drainage was done for cellulitis. The report highlights the importance of dental hygiene during pregnancy, lest life-threatening complications like Ludwig's angina occur, complicating the course of pregnancy.

15.
J Nat Sci Biol Med ; 4(2): 497-9, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24082764

RESUMO

Choriocarcinoma is a highly malignant tumor of the trophoblastic origin. Most cases are present within 1 year of antecedent pregnancy. We present an extremely rare case of choriocarcinoma of the anterior abdominal muscle in a 41-year-old female who presented as mass in anterior abdominal wall 4 months after undergoing a total abdominal hysterectomy with bilateral salpingo oophorectomy for a diagnosis of fibroid uterus. Laparotomy done for the mass revealed it to be an extraperitoneal mass within the rectus muscle that on histopathological examination was confirmed to be primary choriocarcinoma. Computed tomography scan revealed pulmonary metastases and patient was given combination chemotherapy to which she responded well.

16.
J Nat Sci Biol Med ; 2(2): 211-5, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22346239

RESUMO

OBJECTIVE: In childhood Guillain-Barré syndrome (GBS), the clinical profiles using intravenous immunoglobulin (IVIg) in addition to supportive care were studied. MATERIALS AND METHODS: This was a retrospective analysis of 139 children with severe GBS admitted to our respiratory care unit managed with the IVIg as an adjunct intervention to conventional supportive and respiratory care. RESULTS: In our case series of 139 cases, motor weakness was the most common presenting feature. Antecedent illness was found in 66.7% of cases in the preceding two weeks, which included nonspecific illness, acute respiratory infection, diarrhea, and chickenpox. At onset, sensory symptoms (pain and paresthesia) were noted in 59% of the cases and limb weakness in 77%. On admission, a majority (61.54%) were in Hughes neurological disability grading stage V; all had limb weakness at the peak deficit, autonomic disturbance was seen in 35.8%, and bulbar palsy in 52%. Duration of illness was less than three weeks in 67% of cases. The mean duration of ventilation was 21.5 days (range, 5-60 days). CONCLUSIONS: Male preponderance and motor weakness was the most common presenting illness and a majority achieved full recovery in our series. Although IVIg may be useful in the treatment of GBS, the key issue is excellent intensive care unit management.

18.
Artigo em Inglês | MEDLINE | ID: mdl-28112108

RESUMO

Ten patients having hyperkeratosis with moderate to severe fissures on palms and soles were treated with iontophoresis using 5-10% aqueous solution of sodium salicylate. The results were excellent within a period of 3-4 weeks (6-8 sittings each for a period of 10-15 minutes). The treatment was free from the problems of salicylism. Follow-up in some of the reclcitrant cases for 4 months after stop the treatment and with no local application, showed neither any relapse nor deterioration. Sodium salicylate iontophoresis in hyperkeratosis seems to be safe well tolerated and far more effective than the usual local applications of salicylic acid.

19.
Artigo em Inglês | MEDLINE | ID: mdl-28112109

RESUMO

Fifteen subjects having psoriasis on the hand, comprising both sexes, between 22 and 56 years in age and suffering for durations varying from 10 months to 20 years each with a sex and age niatched control were studied. A thermistor thermometer measured the skin temperature in ambient condition at the finger tip and at selected sites on the dorsa of hands and fingers, both at lesion site and lesion-free adjacent ones. In all cases except one, the thermistor readings were significantly lower (p ) in the psoriatic lesions than in the uninvolved adjacent skin. The hands were next subjected to thermal stresses: first by immersion in an ice-water bath at O'C (cold challenge) and later in a hot water bath at 450C (heat challenge) each for a period of 60 seconds. Immediately after each stress period,ithe fingertip temperatures were recorded, in psoriatic subjects, the finger-tip temperature dropped on cold challenge and the amount of drop expressed as percentage of the basal temperature was significantly less (p ) than the corresponding value for the control. There was no significant difference (p 0.05) in the respo se to the heat challenge between psoriat c and normal subjects. It appears that there is some fault in the local vasomotor tone in subjects with hand psoriasis.

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