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2.
Beilstein J Nanotechnol ; 11: 814-820, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32551206

RESUMO

The influence of single-layer graphene on top of a SiO2/Si surface on the orientation of nonplanar lead phthalocyanine (PbPc) molecules is studied using two-dimensional grazing incidence X-ray diffraction. The studies indicate the formation of a mixture of polymorphs, i.e., monoclinic and triclinic forms of PbPc with face-on (lying down) and edge-on (standing up) PbPc orientations, respectively. The formation of monoclinic fractions is attributed to the presence of the graphene layer directing the π interactions between the highly delocalized macrocycles. The competing interfacial van der Waals forces and molecule-molecule interactions lead to the formation of a small fraction of triclinic moieties. The nanoscale electrical characterization of the thin PbPc layer on graphene by means of conducting atomic force microscopy shows enhanced vertical conductance with interconnected conducting domains consisting of ordered monoclinic crystallites through which the charge transfer occurs via tunneling. These results show the importance of a templating layer to induce the formation of a required phase of PbPc suitable for specific device applications.

3.
Phys Chem Chem Phys ; 21(41): 22955-22965, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31599288

RESUMO

The structural organization and its effect on conducting pathways in lead phthalocyanine (PbPc) thin films, a nonplanar phthalocyanine, deposited on Si and highly oriented pyrolytic graphite (HOPG) substrates in the presence of iodine and ammonia vapors are presented. Two-dimensional grazing incidence X-ray diffraction studies reveal that the crystalline ordering in pristine PbPc films on Si and HOPG substrates undergoes a drastic molecular rearrangement and surface reconstruction upon iodine doping. The structural rearrangement leads to morphological changes and higher surface roughness in iodine doped PbPc (I-PbPc) films. The obvious enhancement in the current values of I-PbPc is attributed to the introduction of holes as charge carriers. Nanoscale current mapping reveals the presence of percolation pathways in I-PbPc films, on both Si and HOPG substrates, being responsible for the observed high conductance in contrast to the isolated conducting domains in the pristine PbPc system. The broad distribution of current values across various conducting domains on Si is attributed to a mixture of crystalline phases and disordered fractions of I-PbPc, while the narrow distribution of current values observed in the case of HOPG arises from the majorly disordered PbPc molecules. These films also show enhanced sensitivity towards ammonia that is almost four times higher in magnitude than for pristine PbPc films. The current maps show that the adsorption of ammonia molecules disrupts the iodine percolation pathways, thereby imposing a detrimental effect on the conductivity of the PbPc films.

5.
Bioresour Technol ; 216: 923-30, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27323244

RESUMO

Study creates a scenario for enrichment and selection of ligno-hemicellulose degrading genotypes with anaerobic bioreactor as a model using rice straw, vegetable waste and food waste as substrates. Relative discrimination analysis showed that the hydrolytic pathways and associated microbial communities for ligno-hemicellulose degradation were dominatingly colonized with rice straw as substrate. The dominating bacteria were Caldicellulosiruptor, Fervidobacterium, Cytophaga, Ruminococcus, Thermotoga associated with hemicellulose degradation and Burkholderia, Pandorea, Sphingomonas, Spirochaeta, Pseudomonas for lignocellulose hydrolysis. This was further supported by the abundance of anaerobic aromatic compound degrading genes along with genes for xylanase and xylosidase in rice straw enriched community. The metagenome analysis data was validated by evaluation of the biochemical methane potential for these substrates. Food waste being most amenable substrate yielded 1410mL of biogas/gVS added whereas, biogas yield of 1160mL/gVS and 1080mL/gVS was observed in presence of vegetable waste and rice straw respectively.


Assuntos
Bactérias/metabolismo , Reatores Biológicos/microbiologia , Lignina/metabolismo , Consórcios Microbianos/genética , Polissacarídeos/metabolismo , Bactérias/genética , Biodiversidade , Biocombustíveis , Biotecnologia/instrumentação , Biotecnologia/métodos , Alimentos , Hidrólise , Lignina/genética , Metagenoma , Metano/metabolismo , Oryza/metabolismo , Polissacarídeos/genética , Reprodutibilidade dos Testes
6.
Phys Rev E ; 93: 042706, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27176365

RESUMO

Effect of a polymer network on the threshold voltage of the Fréedericksz transition, Frank elastic constants, switching speed, and the rotational viscosity are investigated in a polymer-stabilized bent-core nematic liquid crystal with different polymer concentrations. These polymer networks form virtual surfaces with a finite anchoring energy. The studies bring out several differences in comparison to similar studies with a calamitic liquid crystal as the nematic host. For example, on varying the polymer content the threshold voltage decreases initially, but exhibits a drastic increase above a critical concentration. A similar feature-reaching a minimum before rising-is seen for the bend elastic constant, which gets enhanced by an order of magnitude for a polymer content of 2.5 wt %. In contrast, the splay elastic constant has a monotonic variation although the overall enhancement is comparable to that of the bend elastic constant. The behavior changing at a critical concentration is also seen for the switching time and the associated rotational viscosity. The presence of the polymer also induces a shape change in the thermal dependence of the bend elastic constant. We explain the features observed here on the basis of images obtained from the optical and atomic force microscopy.

7.
Biosens Bioelectron ; 81: 274-279, 2016 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-26971273

RESUMO

Fluorescent siderophore pyoverdin (PVD) was produced from a soil isolate Pseudomonas monteilii strain MKP 213. The PVD was purified near to homogeneity and applied for the fluorescent chemosensing of various antibiotics in aqueous solution (pH=7.0). Upon addition of ciprofloxacin, PVD showed new UV-vis absorption bands at 252 and 321nm due to an internal charge transfer mechanism. Also, the addition of ciprofloxacin induced a highly selective fluorescence enhancement of PVD with a 13nm blue shift from 458 to 445nm. The combination of a long peptide chain along with the chromophore unit of PVD generates a converging cleft for ciprofloxacin recognition with LOD and LOQ of 7.13µM and 21.6µM, respectively without interference from other studied antibiotics. The association constant (Ka) of PVD with ciprofloxacin was calculated to be as low as 1.40×10(5)M(-1) using Benesi-Hildebrand plot depicting its significance in detection. The pharmaceutical tablet analysis measures the sensing with negligible matrix effect and quantitative recovery.


Assuntos
Antibacterianos/análise , Ciprofloxacina/análise , Corantes Fluorescentes/química , Oligopeptídeos/química , Sideróforos/química , Humanos , Limite de Detecção , Células MCF-7 , Pseudomonas/química , Espectrometria de Fluorescência/métodos
8.
Indian J Pathol Microbiol ; 58(3): 332-4, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26275256

RESUMO

Human dirofilariasis is a rare infection caused by filarial worms of genus Dirofilaria. Subconjunctival dirofilariasis has been reported from Asia, Europe, Italy and Africa. In India majority cases are from Kerala, Karnataka and very few from Maharashtra. We report the rare case of subconjunctival dirofilariasis caused by Dirofilaria repens from Maharashtra, western India.


Assuntos
Dirofilaria repens/isolamento & purificação , Dirofilariose/diagnóstico , Dirofilariose/patologia , Oftalmopatias/diagnóstico , Oftalmopatias/patologia , Animais , Dirofilariose/parasitologia , Oftalmopatias/parasitologia , Humanos , Índia , Masculino , Microscopia , Pessoa de Meia-Idade
9.
J Glob Infect Dis ; 7(2): 60-5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26069424

RESUMO

BACKGROUND: Despite endorsement of the line probe assay (LPA) for the diagnosis of drug-resistant pulmonary tuberculosis patients, there is limited data available on the performance of LPAs in India, especially from high burden states like Maharashtra, for the early diagnosis and detection of drug resistance, in order to initiate timely and appropriate treatment. OBJECTIVE: To evaluate the utility of the line probe assay (LPA) for the early diagnosis of drug-resistant pulmonary tuberculosis as compared to the 'Gold standard' 1% proportion method (PM). MATERIALS AND METHODS: A total of 687 patients suspected of pulmonary tuberculosis were screened. One hundred samples (95 sputum and 5 BAL), positive for Acid Fast Bacilli (AFB) by Ziehl Neelson (ZN) smears, were included in the study. Digested and decontaminated specimens were subjected directly to the LPA (Genotype MTBDR@ plus assay) and were processed in parallel using the conventional culture on the Lowenstein-Jensen (LJ) medium followed by drug susceptibility testing (DST) using the PM. RESULTS: All the 100 samples gave interpretable results on LPA with a turnaround time of 24-48 hours as opposed to six to eight weeks taken by the 1% proportion method. Sensitivity for the detection of rifampicin, isoniazid, and multidrug resistance (MDR) was 98.1, 92.1, and 95%, respectively, with a specificity of 97.8% for rifampicin and 98.33% for MDR detection. It also had the additional advantage of allowing a study of mutation patterns. CONCLUSIONS: High performance characteristics and a short turnaround time makes LPA an excellent diagnostic tool, for an early and accurate diagnosis, in a high MDR- TB-prevalent region, as reflected from our data.

10.
J Rehabil Med ; 46(3): 219-24, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24336984

RESUMO

OBJECTIVE: To evaluate the predictive validity of the Mobility Scale for Acute Stroke (MSAS) in determining discharge destination (home or not home) after an acute stroke. DESIGN: Cohort study. SUBJECTS: Two-hundred and twenty-three patients with acute ischemic or intraparenchymal hemorrhagic, unilateral stroke METHODS: The MSAS was administered as part of the initial physical therapy examination. The Receiver Operating Characteristic determined the optimal MSAS cutoff score associated with discharge home. A multiple logistic regression equation with discharge destination as the criterion variable (home or not home) was conducted with age, length of stay and optimal MSAS cutoff score as covariates. RESULTS: Subjects were discharged home 35.9% (n = 80) and not home 64.1% (n = 143) of the time. Mean age was 68.5 years (standard deviation 1.8). The ROC determined 26 to be the optimal cutoff score for the MSAS. Results of the multiple logistic regression equation indicated that controlling for age and length of stay, only the MSAS cutoff score of 26 reliably predicted discharge to home with an adjusted odds ratio of 57.79 with a 95% confidence interval of 20.09-166.21. CONCLUSION: The MSAS may be useful for predicting discharge destination from the acute hospital after stroke.


Assuntos
Deambulação Precoce/classificação , Tempo de Internação/estatística & dados numéricos , Limitação da Mobilidade , Alta do Paciente/estatística & dados numéricos , Modalidades de Fisioterapia/instrumentação , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral/epidemiologia , Atividades Cotidianas/classificação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Causalgia , Criança , Estudos de Coortes , Comorbidade , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Curva ROC , Reprodutibilidade dos Testes , Acidente Vascular Cerebral/classificação , Resultado do Tratamento , Adulto Jovem
11.
Lett Appl Microbiol ; 58(2): 130-7, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24134431

RESUMO

UNLABELLED: To elucidate the biodiversity of plant growth-promoting (PGP) bacteria in active volcano sites of Barren Island, India, a total of 102 bacteria were isolated and screened for their multifunctional PGP properties. The results revealed that 21 isolates (20.6%) survived heat shock at 72°C and 11 (10.8%) isolates were able to grow exposed to 25% NaCl (w/v). In assaying for PGP properties, 59 (57.8%) isolates shown indole acetic acid (IAA) like substances production, 57 isolates (55.9%) produced siderophore and 34 (33.3%) solubilized inorganic phosphate qualitatively. Whereas in the production of extracellular enzymes, 42 isolates (41.2%) produced protease and amylase, 26 (25.5%) isolates produced lipase and 24 (23.5%) isolates produced cellulase. In antagonistic activity, 30 isolates (29.4%) were found antagonistic against Macrophomina sp., 20 isolates (19.6%) against Rhizoctonia solani and 15 isolates (14.7%) against Sclerotium rolfsii. The results based on 16 rRNA gene sequencing revealed that the PGP bacteria belonged to 22 different species comprising 13 genera. Based on multifunctional properties, nine isolates were further selected to determine the PGP in brinjal and chilli seeds. Of the bacteria tested, the isolate BAN87 showed increased root and shoot length of both the crops followed in plant growth promotion by BAN86 and BAN43. The outcome of this research proves plausible practical applicability of these PGPB for crop production in soils of saline and arid environments. SIGNIFICANCE AND IMPACT OF THE STUDY: The present research shows diverse plant growth-promoting (PGP) bacteria could be isolated from the active volcano site and suggests that volcano sites represent an ecological niche, which harbours a diverse and hitherto largely uncharacterized microbial population with yet unknown and untapped potential biotechnological applications, for example, plant growth promoters, as evidenced from this study. The outcome of this research may have a practical effect on crop production methodologies in saline and arid environment soils.


Assuntos
Bactérias/isolamento & purificação , Bactérias/metabolismo , Desenvolvimento Vegetal , Reguladores de Crescimento de Plantas/isolamento & purificação , Reguladores de Crescimento de Plantas/metabolismo , Microbiologia do Solo , Erupções Vulcânicas , Bactérias/classificação , Bactérias/genética , Biodiversidade , Capsicum/crescimento & desenvolvimento , Índia , Ácidos Indolacéticos/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Sideróforos/metabolismo , Solanum melongena/crescimento & desenvolvimento
14.
Case Rep Obstet Gynecol ; 2012: 593732, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23227382

RESUMO

Abdominal wall metastasis either incisional, drain, or port is rather rare in patients treated for cervical carcinoma. We present a case of a patient who underwent an abdominal radical hysterectomy for a moderately differentiated cervical adenocarcinoma stage Ib1 and presented an incisional site metastasis 36 months after her operation. Moreover, we performed a literature search for abdominal wall metastases after radical hysterectomy for cervical cancer, and we present a table of the relative case reports. After our literature search, we clarified that the median time of recurrence was 14 months (range 1.5 month to 45 months). Thirty-three out of 42, 8/42, and 1/42 were squamous, adeno-, and adenosquamous carcinomas, respectively. Wide excision was performed in 30/37 cases of which we have information regarding the treatment option, while 11/37 and 13/37 underwent radiotherapy and chemotherapy, respectively. The possible mechanism of such a metastasis as well as the treatment options is discussed.

15.
Case Rep Obstet Gynecol ; 2012: 467240, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23133766

RESUMO

Sister Mary Joseph's nodule metastasis is a rather rare finding. The primary malignancy in women is usually ovarian, endometrial, gastric, or pancreatobiliary tree cancer. We present a case of an 87-year-old patient with Sister Mary Joseph's nodule metastasis caused by a primary peritoneal malignancy. Through a literature search, we also discuss the pathophysiology, diagnostic approach, management, and prognosis of such a condition.

16.
Br J Cancer ; 106(3): 482-9, 2012 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-22233925

RESUMO

BACKGROUND: Carboplatin remains a first-line agent in the management of epithelial ovarian cancer (EOC). Unfortunately, platinum-resistant disease ultimately occurs in most patients. Using a novel EOC cell line with acquired resistance to carboplatin: PEO1CarbR, genome-wide micro-array profiling identified the cyclin-dependent kinase inhibitor p57(Kip2) as specifically downregulated in carboplatin resistance. Presently, we describe confirmation of these preliminary data with a variety of approaches. METHODS: Cytotoxicity testing (MTT) and cell cycle blockade assessed drug responsiveness. Methylation specific PCR and pyrosequencing identified sites of promoter methylation in p57(Kip2). siRNA to p57(Kip2) was used to look at the changes in apoptosis of carboplatin treated EOC cells. EOC tissues (20 cases) were assessed for mRNA levels of p57(Kip2). RESULTS: Carboplatin resistance was reversed using 5-aza-cytidine in vitro. Promoter methylation sites and preferential sensitivity to seliciclib were seen in PEO1CarbR cells. Silencing p57(Kip)2 decreased the apoptotic response to the effects of platinum but produced sensitisation to seliciclib. EOC biopsies indicated an association of high levels of p57(Kip2)mRNA with complete responses to chemotherapy and improved outcome. CONCLUSION: We conclude that p57(Kip2) is a candidate biomarker of platinum sensitivity/resistance in EOC and such cases may show preferential response to the cyclin-dependent kinase inhibitor seliciclib.


Assuntos
Inibidor de Quinase Dependente de Ciclina p27/genética , Regulação para Baixo , Resistencia a Medicamentos Antineoplásicos , Neoplasias Ovarianas/metabolismo , Antineoplásicos/farmacologia , Carboplatina/uso terapêutico , Linhagem Celular Tumoral/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Metilação de DNA , Relação Dose-Resposta a Droga , Epigênese Genética , Feminino , Humanos , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Purinas/farmacologia , Roscovitina
17.
Indian J Microbiol ; 52(2): 137-44, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23729873

RESUMO

Trichoderma, soil-borne filamentous fungi, are capable of parasitising several plant pathogenic fungi. Twelve isolates of Trichoderma spp. isolated from different locations of South Andaman were characterized for their cultural, morphological and antagonistic activity against soil borne and foliar borne pathogens. The sequencing of these isolates showed seven different species. The isolates revealed differential reaction patterns against the test pathogens viz., Sclerotium rolfsii, Colletotrichum gloeosporioides and C. capsici. However, the isolates, TND1, TWN1, TWC1, TGD1 and TSD1 were most effective in percentage inhibition of mycelial growth of test pathogens. Significant chitinase and ß-1,3-glucanase activities of all Trichoderma isolates has been recorded in growth medium. T. viride was found with highest chitinase whereas T. harzianum was recorded with highest ß-1,3-glucanase activities.

18.
J Environ Sci (China) ; 23(6): 975-82, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22066220

RESUMO

A new bacterial strain DMT-7 capable of selectively desulfurizing dibenzothiophene (DBT) was isolated from diesel contaminated soil. The DMT-7 was characterized and identified as Lysinibacillus sphaericus DMT-7 (NCBI GenBank Accession No. GQ496620) using 16S rDNA gene sequence analysis. The desulfurized product of DBT, 2-hydroxybiphenyl (2HBP), was identified and confirmed by high performance liquid chromatography analysis and gas chromatography-mass spectroscopy analysis respectively. The desulfurization kinetics revealed that DMT-7 started desulfurization of DBT into 2HBP after the lag phase of 24 hr, exponentially increasing the accumulation of 2HBP up to 15 days leading to approximately 60% desulfurization of the DBT. However, further growth resulted into DBT degradation. The induced culture of DMT-7 showed shorter lag phase of 6 hr and early onset of stationary phase within 10 days for desulfurization as compared to that of non-induced culture clearly indicating the inducibility of the desulfurization pathway of DMT-7. In addition, Lysinibacillus sphaericus DMT-7 also possess the ability to utilize broad range of substrates as sole source of sulfur such as benzothiophene, 3,4-benzo DBT, 4,6-dimethyl DBT, and 4,6-dibutyl DBT. Therefore, Lysinibacillus sphaericus DMT-7 could serve as model system for efficient biodesulfurization of diesel and petrol.


Assuntos
Bacillus/metabolismo , Biodegradação Ambiental , Gasolina , Microbiologia do Solo , Poluentes do Solo/metabolismo , Tiofenos/metabolismo , Bacillus/classificação , Bacillus/genética , Bacillus/crescimento & desenvolvimento , Meios de Cultura/química , Poluentes do Solo/química , Tiofenos/química
19.
Indian J Pharm Sci ; 73(3): 320-3, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-22457560

RESUMO

A simple, sensitive and reproducible method was developed and validated for the simultaneous estimation of diethylcarbamazine and levocetirizine in its tablet formulation by reverse phase high performance liquid chromatography using Waters1515 HPLC with UV detector at the λ(max) of 224 nm, using Princeton Sphere-100 C(18) (250×4.6 mm. 5 µ) column. The mobile phase used was 20mM potassium dihydrogen orthophosphate buffer (pH: 3.2):acetonitrile (50:50 v/v) with isocratic flow (flow rate 1 ml/min) and the pH was adjusted with orthophosphoric acid. Losartan potassium was used as an internal standard. The compounds diethylcarbamazine, levocetirizine and losartan potassium were eluted at 2.12, 4.27 and 5.96 min, respectively. The peaks were eluted with better resolution. The method was accurate with assay values of 96.32 and 93.04% w/w, precise (%RSD) with intra-day 1.72 and 1.89 and inter-day 1.85 and 1.92, recoveries 102.86 and 101.1% w/w, which are very sensitive with limit of detections (LOD)'s 75, 50 ng/ml and limit of quantification (LOQ)'s 100, 75 ng/ml and linear with R(2) values 0.994 in the range of 5 to 30 µg/ml 0.1 to 1 µg/ml for diethylcarbamazine and levocetirizine, respectively. Hence this method can be applied for quantification of different formulations containing diethylcarbamazine and levocetirizine simultaneously.

20.
J Geriatr Phys Ther ; 32(1): 15-21, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19856631

RESUMO

PURPOSE: Lumbar spinal stenosis (LSS), a degenerative disease encountered in adults > 65 years, is a leading cause of back and lower extremity pain, weakness, impaired sensation and balance. The purpose of this pilot study was to determine whether patients with LSS demonstrate increased postural sway and impaired balance, compared to healthy counterparts. METHODS: Patients with varying severity of LSS and age and gender matched controls were recruited from a tertiary care hospital, yielding 6 case-control pairs. Subjects completed generic health status (SF-36), disease specific scales (LSS) and demographic forms. Medical comorbidities were extracted from medical records. Patients received a musculoskeletal examination and performed the Functional Reach (FR) and Timed "Up & Go" (TUG) tests. Stabilogram diffusion analysis (SDA) measured center of pressure (COP). RESULTS: Patients reported moderately impaired physical function, lumbar flexibility and walked with a slightly wider base of support. TUG scores did not differ across groups. Significantly limited FR scores indicated that patients had impaired dynamic balance and were at a greater risk of falls. SDA demonstrated no significant difference in sway for patients and controls; however, patients demonstrated significantly higher critical values for antero-posterior (AP) displacement than controls. CONCLUSION: Patients with LSS, even those with mild symptoms, demonstrate decreased function and balance, particularly in the AP direction. Physical examination measures and TUG are not adequate to assess balance impairments or risk of falls in these patients. Measures such as the FR and SDA may be useful in detecting the aspects of balance impairments perceived by patients.


Assuntos
Envelhecimento/fisiologia , Avaliação da Deficiência , Vértebras Lombares/fisiopatologia , Equilíbrio Postural/fisiologia , Estenose Espinal/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Estudos Transversais , Feminino , Avaliação Geriátrica , Humanos , Projetos Piloto , Amplitude de Movimento Articular , Sensibilidade e Especificidade , Inquéritos e Questionários , Caminhada
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