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1.
J Pharm Sci ; 113(3): 772-784, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38043682

RESUMO

The main objective of the experiment is to develop and evaluate hydrogel-bearing nanostructured lipid carriers (NLCs) loaded with ketoconazole (KTZ) for the effective treatment of candidiasis. The eugenol was used as a liquid lipid (excipient) for the development of KTZ-loaded NLCs and was explored for anti-fungal effect. The production of NLCs involves high energy processes to generate spherical, uniform particles, having a higher percentage of entrapment efficiency (%EE) for KTZ with 89.83 ± 2.31 %. The data from differential scanning calorimeter (DSC), powder x-ray diffraction (PXRD), and attenuated total reflectance (ATR) demonstrated the KTZ dispersion in NLCs. The NLCs loaded hydrogel possessed optimum spreadability and exhibited shear thinning behavior, indicating the ease of application of the final formulation. The 6.41-fold higher transdermal flux (Jss) was governed for KTZ from KTZ-NLC than coarse-KTZ, which explains the usefulness of NLCs. The KTZ-NLCs exhibited significant 2.58 and 6.35-fold higher retention in the stratum corneum and viable epidermis of the skin. The cell cytotoxicity studies using human dermal fibroblast cell (HDFS) lines depicted the usefulness of NLCs in reducing cell toxicities for KTZ. The KTZ-NLCs were found to inhibit planktonic growth and hyphal transition and showed a larger zone of inhibition against C. albicans strains with a MIC-50 value of 0.39 µg/mL. The antibiofilm activity of KTZ-NLCs at lower concentrations, in contrast to plain KTZ, explained the interaction of developed NLCs with fungal membranes. The overall results depicted the effectiveness of the loading KTZ in the lipid matrix to achieve antifungal activity against C. albicans.


Assuntos
Candida albicans , Nanoestruturas , Humanos , Eugenol/farmacologia , Portadores de Fármacos/farmacologia , Hidrogéis/farmacologia , Lipídeos/farmacologia , Tamanho da Partícula
2.
Rev. esp. med. nucl. imagen mol. (Ed. impr.) ; 42(6): 374-379, nov.- dec. 2023. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-227101

RESUMO

Objetivo Evaluar mediante linfogammagrafía in vivo y con detección SPECT/TC los patrones de drenaje linfático de los tumores del seno paranasal (SPN). Confirmar o rebatir la creencia de que el ganglio linfático retrofaríngeo (GLRF) se erige en el ganglio de drenaje índice para dichos tumores. Métodos Estudio de cohorte prospectivo realizado en pacientes con tumores del SPN no tratados previamente y sin evidencia clínico-radiológica de metástasis a nivel ganglionar. La linfogammagrafía se realizó mediante la inyección peritumoral de sulfuro coloidal marcado con [99m]TcO4 y asistida por endoscopia nasal. Las inyecciones se clasificaron como anteriores o posteriores en función de una línea vertical que pasaba por el orificio del seno maxilar. Resultados Se incluyeron 17 pacientes. La linfogammagrafía identificó satisfactoriamente 17 ganglios centinelas en 15 pacientes, y no pudo evidenciarlo (fracaso de la linfogammagrafía) en 2 pacientes. Se observó que los lugares predominantes de drenaje del ganglio centinela fueron el GLRF (n=8; 47%) y el nivel I (n=7; 42%). Se identificó drenaje ocasional en el ganglio periparotídeo (n=1) y en el nivel II (n=1). Se observó drenaje linfático contralateral en 2 pacientes (en el nivel I y GLRF, respectivamente). Las inyecciones anteriores drenaron predominantemente hacia el nivel I (6/8) y a GLRF (2/8), mientras que las inyecciones posteriores drenaron predominantemente a GLRF (6/7). El riesgo relativo de que el GLRF fuera identificado como ganglio centinela fue significativamente mayor en las inyecciones administradas posteriormente respecto a las administradas anteriormente (RR: 3,43; IC 95%: 1,0-11,8; p=0,05). Conclusión El GLRF es considerado un ganglio de drenaje frecuente asociado a los tumores del seno nasal, y merece su atención rutinaria en todos los casos de tumor del seno nasal (AU)


Objective To evaluate by in vivo lymphoscintigraphy and SPECT-CT imaging, the lymphatic drainage patterns of para-nasal sinus (PNS) tumours. To confirm or refute the belief of the retropharyngeal lymph node (RPLN) being the significant draining lymph node for such tumours. Methods Prospective cohort study conducted on previously untreated PNS tumours with no clinico-radiological evidence of lymph node metastasis. Lymphoscintigraphy undertaken by nasal endoscopic assisted peritumoral injection of 99mTc sulphur colloid. Injections were classified as anterior or posterior as per a vertical line along the maxillary sinus ostium. Results Seventeen patients were included. Lymphoscintigraphy successfully identified 17 sentinel nodes in 15 patients and was unsuccessful (lymphoscintigraphy failure) in 2 patients. Predominant sites of sentinel lymphatic drainage were noted to be the RPLN (n=8; 47%) and level I (n=7; 42%). Occasional drainage was identified at the peri-parotid node (n=1) and at level II (n=1). Contralateral drainage was noted in 2 patients (level I-1 and RPLN-1). Anterior injections drained predominantly to level I (6/8) and RPLN (2/8), while posterior injections drained predominantly to the RPLN (6/7). The relative risk of RPLN being identified as the sentinel node was significantly higher for posteriorly placed injections than for anteriorly placed injections (RR: 3.43; 95% CI: 1.0-11.8; P=.05). Conclusion The RPLN is noted as a frequent draining node for sino-nasal tumours and merits routine attention in all sino-nasal tumours. The radio-colloid SPECT-CT technique described here offers an excellent in vivo technique to further explore and validate the lymphatic drainage pathways of these tumours (AU)


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Linfocintigrafia/métodos , Neoplasias Nasais/diagnóstico por imagem , Linfonodo Sentinela/diagnóstico por imagem , Estadiamento de Neoplasias , Estudos Prospectivos , Estudos de Coortes
3.
SAR QSAR Environ Res ; : 1-20, 2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-37941423

RESUMO

The fast-increasing number of commercially produced chemicals challenges the experimental ecotoxicity assessment methods, which are costly, time-consuming, and dependent on the sacrifice of animals. In this regard, Quantitative Structure-Property/Activity Relationships (QSPR/QSAR) have led the way in developing ecotoxicity assessment models. In this study, QSAR models have been developed using the pEC50 values of 82 diverse agrochemicals or agro-molecules against a planktonic crustacean Daphnia magna with easily interpretable 2D descriptors. Moreover, a link among octanol-water partition coefficient (KOW), bio-concentration factor (BCF), and critical body residue (CBR) has been addressed, and their imputation for the prediction of the toxicity endpoint (EC50) has been done with an objective of the advanced exploration of several ecotoxicological parameters for toxic chemicals. The developed partial least squares (PLS) models were validated rigorously and proved to be robust, sound, and immensely well-predictive. The final Daphnia toxicity model derived from experimental derived properties along with computed descriptors emerged better in statistical quality and predictivity than those obtained solely from computed descriptors. Additionally, the pEC50 and other important properties (log KOW, log BCF, and log CBR) for a set of external agro-molecules, not employed in model development, were predicted to show the predictive ability of the models.

4.
Artigo em Inglês | MEDLINE | ID: mdl-37399973

RESUMO

OBJECTIVE: To evaluate by in- vivo lymphoscintigraphy and SPECT-CT imaging, the lymphatic drainage patterns of para-nasal sinus(PNS) tumors. To confirm or refute the belief of the retropharyngeal lymph node (RPLN) being the significant draining lymph node for such tumors. METHODS: Prospective cohort study conducted on previously untreated PNS tumors with no clinico-radiological evidence of lymph node metastasis. Lymphoscintigraphy undertaken by nasal endoscopic assisted peritumoral injection of 99mTc Sulfur colloid. Injections were classified as anterior or posterior as per a vertical line along the maxillary sinus ostium. RESULTS: 17 patients were included. Lymphoscintigraphy successfully identified 17 sentinel nodes in 15 patients and was unsuccessful (lymphoscintigraphy failure) in 2 patients. Predominant sites of sentinel lymphatic drainage were noted to be the RPLN (n = 8; 47%), and Level I (n = 7; 42%). Occasional drainage was identified at the peri-parotid node(n = 1) and at Level II (n = 1). Contralateral drainage was noted in 2 patients (level I-1 and RPLN-1). Anterior injections drained predominantly to Level I (6/8) and RPLN (2/8), while posterior injections drained predominantly to the RPLN ( 6/7). The relative risk of RPLN being identified as the sentinel node was significantly higher for posteriorly placed injections than for anteriorly placed injections (RR- 3.43; 95% CI-1.0-11.8, p = 0.05). CONCLUSION: The RPLN is noted as a frequent draining node for sino-nasal tumours and merits routine attention in all sino-nasal tumors. The radio-colloid SPECT-CT technique described here offers an excellent in-vivo technique to further explore and validate the lymphatic drainage pathways of these tumours.


Assuntos
Linfocintigrafia , Biópsia de Linfonodo Sentinela , Humanos , Linfocintigrafia/métodos , Biópsia de Linfonodo Sentinela/métodos , Estudos Prospectivos , Compostos Radiofarmacêuticos , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Metástase Linfática/diagnóstico por imagem , Coloides
5.
Langmuir ; 39(11): 3934-3941, 2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36883239

RESUMO

Deicing has significant relevance in various applications such as transportation, energy production, and telecommunication. The use of surface acoustic waves (SAWs) is an attractive option for deicing as it offers several advantages such as localized heating, in situ control, low power, and system integration for highly efficient deicing. Here, we report an understanding of the dynamics of deicing of microlitre volume water droplets (1 to 30 µL) exposed to low power (0.3 W) SAW actuation using an interdigitated electrode on a piezoelectric (LiNbO3) substrate. We study the time variation of the volume of liquid water from the onset of SAW actuation to complete deicing, which takes 2.5 to 35 s depending on the droplet volume. The deicing phenomenon is attributed to acoustothermal heating which is found to be greatly influenced by the loss of ice adhesion with the substrate and the acoustic streaming within the liquid water. Acoustothermal heating inside the droplet is characterized by the temperature distribution inside the droplet using infrared thermography, and acoustic streaming is observed using dye-based optical microscopy. A rapid enhancement in deicing is observed upon the detachment of ice from the substrate and the onset of acoustic streaming, marked by a sudden increase in the liquid water volume, droplet temperature, and heat transfer coefficient. The deicing time is found to increase linearly with droplet volume as observed from experiments and further verified using a theoretical model. Our study provides an improved understanding of the recently introduced SAW-based deicing technique that may open up the avenue for a suitable alternative to standard deicing protocols.

6.
Langmuir ; 38(15): 4763-4773, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35395155

RESUMO

Microwell arrays are ideal platforms for cell culturing, cell separation, and low-volume liquid handling. The ability to manipulate droplets in microwells could open up the opportunity for developing new biochemical assays. Here, we study the trapping of aqueous droplets in an oil-filled microwell driven by the application of nanometer amplitude vibrations called surface acoustic waves (SAW). We elucidate the dynamics of the droplet within the vortex toward the final trapping location and the physics of the trapping phenomenon using a theoretical model by considering the relevant forces. Our study revealed that the combined effect of acoustic radiation and hydrodynamic forces leads to droplet migration and trapping. We demarcate the trapping and nontrapping regimes in terms of the minimum critical input power required for the trapping of droplets of different sizes and densities. We find that the critical power varies as the square of the droplet size and is higher for a denser droplet. The effects of input power and droplet size on the trapping location and trapping time are also studied.


Assuntos
Hidrodinâmica , Som , Modelos Teóricos , Vibração , Água
7.
Phys Rev E ; 105(3-2): 035103, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35428152

RESUMO

We study particle trapping driven by the axial primary radiation force (A-PRF) in shaped traps exposed to standing bulk acoustic waves (S-BAW) using numerical simulations and experiments. The utilization of the stronger A-PRF as the main retention force is a consequence of standing-wave formation along the flow direction, instead of the orthogonal direction as in the case of traditionally used lateral-PRF S-BAW trapping setups. The study of particle dynamics reveals that the competition between A-PRF and viscous drag force governs particle trajectory. The ratio of the acoustic energy to the viscous work (ß) provides a general criterion for particle trapping at a distinctive off-node site that is spatially controllable. Particles get trapped for ß≥ß_{cr} at some distance away from the nodal plane and the distance varies as ß^{-c} (c=0.6-1.0). The use of A-PRF as the retention force could potentially allow traditional S-BAW trapping systems to envisage high-throughput advancements surpassing the current standards in cell-handling unit operations.

8.
J Acoust Soc Am ; 150(1): 307, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34340505

RESUMO

The dynamical motion of a pair of microparticles exposed to acoustic standing waves and located at the pressure nodal plane is studied using numerical simulations and experiments. The insight into their dynamical behavior along the pressure nodal plane due to the competition between the axial primary radiation and interparticle forces is elucidated. An expression for axial primary radiation force acting on a particle is derived, and the particle dynamics is simulated using fluid-structure interaction model based on the arbitrary Lagrangian-Eulerian method. Considering the total radiation force acting on a particle is the sum of the axial primary radiation force and the interparticle force, three distinct dynamical regimes are observed depending upon the relative magnitudes of the acoustic forces which in turn depend on the gradient of the acoustic energy density. Acceleration, deceleration, and constant velocity motion of the pair of approaching particles are observed, which are explained by the interplay of the acoustic and non-acoustic forces. The dynamical motion of the pair of particles predicted using the model is in very good agreement with the experimental observations.

9.
J Neurol Sci ; 423: 117358, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33653604

RESUMO

Reactivation of Human Endogenous Retrovirus K (HERV-K), subtype HML-2, has been associated with pathophysiology of amyotrophic lateral sclerosis (ALS). We aimed to assess the efficacy of antiretroviral therapy in inhibiting HML-2 in patients with ALS and a possible association between the change in HML-2 levels and clinical outcomes. We studied the effect of 24-weeks antiretroviral combination therapy with abacavir, lamivudine, and dolutegravir on HML-2 levels in 29 ALS patients. HML-2 levels decreased progressively over 24 weeks (P = 0.001) and rebounded within a week of stopping medications (P = 0.02). The majority of participants (82%), defined as "responders", experienced a decrease in HML-2 at week 24 of treatment compared to the pre-treatment levels. Differences in the evolution of some of the clinical outcomes could be seen between responders and non-responders: FVC decreased 23.69% (SE = 11.34) in non-responders and 12.71% (SE = 8.28) in responders. NPI score decreased 91.95% (SE = 6.32) in non-responders and 53.05% (SE = 10.06) in responders (P = 0.01). Thus, participants with a virological response to treatment showed a trend for slower progression of the illness. These findings further support the possible involvement of HML-2 in the clinical course of the disease.


Assuntos
Esclerose Amiotrófica Lateral , Retrovirus Endógenos , Infecções por HIV , Esclerose Amiotrófica Lateral/tratamento farmacológico , Esclerose Amiotrófica Lateral/genética , Infecções por HIV/tratamento farmacológico , Humanos
10.
Langmuir ; 37(4): 1578-1587, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33478219

RESUMO

Microwell arrays are amongst the most commonly used platforms for biochemical assays. However, the coalescence of droplets that constitute the dispersed phase of suspensions housed within microwells has not received much attention to date. Herein, we study the coalescence of droplets in a two-phase system in a microwell driven by surface acoustic waves (SAWs). The microwell structure, together with symmetric exposure to SAW irradiation, coupled from beneath the microwell via a piezoelectric substrate, gives rise to the formation of a pair of counter-rotating vortices that enable droplet transport, trapping, and coalescence. We elucidate the physics of the coalescence phenomenon using a scaling analysis of the relevant forces, namely, the acoustic streaming-induced drag force, the capillary and viscous forces associated with the drainage of the thin continuous phase film between the droplets and the van der Waals attraction force. We confirm that droplet-droplet interface contact is established through the formation of a liquid bridge, whose neck radius grows linearly in time in the preceding viscous regime and proportionally with the square root of time in the subsequent inertial regime. Further, we investigate the influence of the input SAW power and droplet size on the film drainage time and demarcate the coalescence and non-coalescence regimes to derive a criterion for the onset of coalescence. The distinct deformation patterns observed for a pair of contacting droplets in both the regimes are elucidated and the possibility for driving concurrent coalescence of multiple droplets is demonstrated. We expect the study will find relevance in the demulsification of immiscible phases and the mixing of samples/reagents within microwells for a variety of biochemical applications.

11.
Int J Tuberc Lung Dis ; 24(12): 1272-1278, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33317671

RESUMO

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is common among non-smokers exposed to solid fuel combustion at home. Different clinical characteristics in these patients may have significant therapeutic and prognostic implications.METHODS: We used medical record review and a questionnaire among COPD patients at 15 centres across India to capture data on demographic details, different types of exposures and clinical characteristics. Chest radiography and pulmonary function testing were performed in all 1984 cases; C-reactive protein and exhaled breath nitric oxide were measured wherever available.RESULTS: There were 1388 current or ex-smokers and 596 (30.0%) non-smokers who included 259 (43.5%) male and 337 (56.5%) female patients. Sputum production was significantly more common in smokers with COPD (P < 0.05). The frequency of acute symptomatic worsening, emergency visits and hospitalisation were significantly higher (P < 0.05) in non-smokers with COPD; however, intensive care unit admissions were similar in the two groups. There was no significant difference with respect to the use of bronchodilators, inhalational steroids or home nebulisation among smoker and non-smoker patients. The mean predicted forced expiratory volume in 1 sec in smokers (43.1%) was significantly lower than in non-smokers (46.5%).CONCLUSION: Non-smoker COPD, more commonly observed in women exposed to biomass fuels, was characterised by higher rate of exacerbations and higher healthcare resource utilisation.


Assuntos
não Fumantes , Doença Pulmonar Obstrutiva Crônica , Broncodilatadores/uso terapêutico , Feminino , Volume Expiratório Forçado , Humanos , Índia/epidemiologia , Masculino , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/epidemiologia
12.
Vet World ; 13(10): 2133-2141, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33281347

RESUMO

Urinalysis is the examination of normal and abnormal constituents of urine. It is an easy, cheap, and vital initial diagnostic test for veterinarians. Complete urinalysis includes the examination of color, odor, turbidity, volume, pH, specific gravity, protein, glucose, ketones, blood, erythrocytes, leukocytes, epithelial cells, casts, crystal, and organisms. Semi-quantitative urine analysis with urine dipsticks, as well as an automatic analyzer, provides multiple biochemical data. Contamination is almost entirely avoided if the protocols for ensuring a proper sample have been followed, as mentioned still consideration must be given to the likelihood of contamination, even if the sample is correctly obtained. Interpretation of urinalysis will be doubtful if the knowledge of the interference is limited. Well-standardized urinalysis, when correlated in the context of history, clinical findings, and other diagnostic test results, can identify both renal and non-renal disease. This paper reviews significance of different components of urinalysis of dog and cat, such as collection, storage, examination, interpretation, and common causes of error in the result.

13.
BMC Psychiatry ; 19(1): 225, 2019 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-31337373

RESUMO

BACKGROUND: Cognitive Bias Modification (CBM) has been used successfully as a computer-based intervention in disorders such as anxiety. However, CBM to modify interpretations of ambiguous information relevant to paranoia has not yet been tested. We conducted a qualitative investigation of a novel intervention called CBM for paranoia (CBM-pa) to examine its acceptability in patients with psychosis. METHODS: Eight participants with psychosis who completed CBM-pa were identified by purposive sampling and invited for a semi-structured interview to explore the facilitators and barriers to participation, optimum form of delivery, perceived usefulness of CBM-pa and their opinions on applying CBM-pa as a computerised intervention. The interviews were transcribed and analysed using thematic analysis by researchers working in collaboration with service users. RESULTS: Themes emerged relating to participants' perception about delivery, engagement, programme understanding, factors influencing experience, perceived impact and application of CBM-pa. CBM-pa was regarded as easy, straightforward and enjoyable. It was well-accepted among those we interviewed, who understood the procedure as a psychological intervention. Patients reported that it increased their capacity for adopting alternative interpretations of emotionally ambiguous scenarios. Although participants all agreed on the test-like nature of the current CBM-pa format, they considered that taking part in sessions had improved their overall wellbeing. Most of them valued the computer-based interface of CBM-pa but favoured the idea of combining CBM-pa with some form of human interaction. CONCLUSIONS: CBM-pa is an acceptable intervention that was well-received by our sample of patients with paranoia. The current findings reflect positively on the acceptability and experience of CBM-pa in the target population. Patient opinion supports further development and testing of CBM-pa as a possible adjunct treatment for paranoia. TRIAL REGISTRATION: Current Controlled Trials ISRCTN: 90749868 . Retrospectively registered on 12 May 2016.


Assuntos
Terapia Cognitivo-Comportamental/métodos , Transtornos Paranoides/terapia , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Transtornos Psicóticos/terapia , Adulto , Feminino , Humanos , Masculino , Transtornos Paranoides/psicologia , Transtornos Psicóticos/psicologia , Pesquisa Qualitativa , Interface Usuário-Computador
14.
Clin Radiol ; 74(1): 3-12, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30031589

RESUMO

Vascular disease, whether it be atherosclerosis, inflammatory, or hereditary vasculitide, is a systemic disorder with disease in one territory predictive of disease in another. Despite this, current approaches focus on single-territory assessment ignoring the global burden of disease. Advances in MRI have enabled us to surmount previous limitations and expand our approach to such conditions with the ability to simultaneously assess the entirety of the arterial tree in a single examination, allowing a staging examination as it were, of the vascular health in its totality. This review will cover the acquisition technique, reporting, clinical utility, and current evidence base for such an approach.


Assuntos
Angiografia por Ressonância Magnética , Imagem Corporal Total , Vasos Sanguíneos/diagnóstico por imagem , Humanos , Angiografia por Ressonância Magnética/métodos , Doenças Vasculares/diagnóstico por imagem , Imagem Corporal Total/métodos
15.
Sci Rep ; 7: 41713, 2017 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-28181521

RESUMO

Since its discovery, graphene has held great promise as a two-dimensional (2D) metal with massless carriers and, thus, extremely high-mobility that is due to the character of the band structure that results in the so-called Dirac cone for the ideal, perfectly ordered crystal structure. This promise has led to only limited electronic device applications due to the lack of an energy gap which prevents the formation of conventional device geometries. Thus, several schemes for inducing a semiconductor band gap in graphene have been explored. These methods do result in samples whose resistivity increases with decreasing temperature, similar to the temperature dependence of a semiconductor. However, this temperature dependence can also be caused by highly diffusive transport that, in highly disordered materials, is caused by Anderson-Mott localization and which is not desirable for conventional device applications. In this letter, we demonstrate that in the diffusive case, the conventional description of the insulating state is inadequate and demonstrate a method for determining whether such transport behavior is due to a conventional semiconductor band gap.

17.
Sci Rep ; 6: 19939, 2016 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-26860789

RESUMO

Reports of metallic behavior in two-dimensional (2D) systems such as high mobility metal-oxide field effect transistors, insulating oxide interfaces, graphene, and MoS2 have challenged the well-known prediction of Abrahams, et al. that all 2D systems must be insulating. The existence of a metallic state for such a wide range of 2D systems thus reveals a wide gap in our understanding of 2D transport that has become more important as research in 2D systems expands. A key to understanding the 2D metallic state is the metal-insulator transition (MIT). In this report, we explore the nature of a disorder induced MIT in functionalized graphene, a model 2D system. Magneto-transport measurements show that weak-localization overwhelmingly drives the transition, in contradiction to theoretical assumptions that enhanced electron-electron interactions dominate. These results provide the first detailed picture of the nature of the transition from the metallic to insulating states of a 2D system.

18.
Asian Pac J Cancer Prev ; 16(15): 6397-400, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26434849

RESUMO

Cervical cancer is the second most common gynecological malignancy worldwide. According to HPV Information Centre, Spain (Aug'2014), in India approximately 1,22,844 women are diagnosed with the disease every year and of them 67,477 die due to the disease. CaCx is said to be mediated by HPV but recent data published reveal the role of Oxidative Stress in different Cancers. Arsenic is also one of the agents for causing Oxidative Stress. Arsenic has been linked with different types of cancer. Arsenic is considered responsible for generation of free radicals and eventually for apoptosis. Early diagnosis of CaCx is presently a matter of concern and clinical presentation in advanced stages become difficult for complete clinical response. For determination of oxidative stress, Malondialdehyde (MDA) was taken as an identifier and arsenic estimation was performed with the help of Atomic Absorption Spectrometer (AAS). RBC count and Haemoglobin levels were performed according to standard protocol. MDA was in direct proportion with arsenic concentration and inversely proportional to RBC and Haemoglobin in CaCx patients. Arsenic is one of the major causative agents for oxidative stress and hence may be a risk factor leading to cancer including CaCx.


Assuntos
Arsênio/sangue , Hemoglobinas/metabolismo , Malondialdeído/sangue , Neoplasias do Colo do Útero/sangue , Arsênio/toxicidade , Estudos de Casos e Controles , Contagem de Eritrócitos , Feminino , Humanos , Índia , Estresse Oxidativo , Fatores de Risco , Espectrofotometria Atômica
19.
Artigo em Inglês | MEDLINE | ID: mdl-25004904

RESUMO

Phytohaemagglutinin (PHA) is a lectin obtained from Phaseolus vulgaris (red kidney beans), that acts as a mitogen in human leucocyte culture and is commercially available from Gibco. This PHA (Gibco) was found to be very expensive, hence other inexpensive sources that can be used in all kinds of cytogenetics labs (rich and poor), were attempted. One such successful attempt was PHA extract from seeds of P.vulgaris. This paper details the methodology of extraction and application of PHA from seeds of P.vulgaris. Attempts has been made to identify the chemical and physical properties of the products in the extract, analyzed by various spectroscopic and analytical techniques. The analysis clearly indicates that the product from Phaseolus seeds extract was found to be similar to the commercially available PHA (Gibco) in the cytogenetic study of human leucocyte cultures. The present study enforces the possible utility of the plant extract directly for human leucocyte cultures.


Assuntos
Análise Citogenética/métodos , Phaseolus/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Sementes/química , Catarata/genética , Células Cultivadas , Cromatografia em Camada Delgada , Aberrações Cromossômicas , Diabetes Mellitus Tipo 2/genética , Humanos , Leucócitos/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Fito-Hemaglutininas , Extratos Vegetais/análise , Espectrofotometria Ultravioleta
20.
Ann R Coll Surg Engl ; 96(2): 121-6, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24780669

RESUMO

INTRODUCTION: This study aimed to determine whether ethnic differences show different patterns of arterial disease in the lower limb. METHODS: A prospective analysis of 100 consecutive patients with 160 lower limb arteriograms was performed looking at the pattern of disease with relation to ethnicity in Trinidad and Tobago. RESULTS: There were 53 male and 47 female patients with an age range of 43-90 years (mean: 66 years). Of the 100 patients, 45 were of East Indian descent, 36 of Afro-Caribbean descent, 14 of mixed descent and 5 had other backgrounds. There were 32 smokers and 69 diabetics. The most commonly affected artery in East Indians was the anterior tibial artery (ATA, 70%) followed by the peroneal artery (60%), superficial femoral artery (SFA, 60%), posterior tibial artery (PTA, 57%) and tibioperoneal trunk (TPT, 39%). In Afro-Caribbeans, the most commonly affected artery was the ATA (79%) followed by the PTA (74%), peroneal artery (66%) and TPT (55%). The mixed group showed the PTA (85%) to be most diseased followed by the peroneal artery (75%), ATA (70%), SFA (70%), dorsalis pedis artery (DPA, 60%) and TPT (50%). Overall, the most diseased vessel in all groups was the ATA (73%) followed by the PTA (66%), peroneal artery (64%), SFA (59%), TPT (46%), DPA (38%), popliteal artery (31%) and medial plantar artery (MPA, 29%), with the proximal vessels not being affected severely. CONCLUSIONS: Ethnic divisions were only statistically significant (p<0.05) with East Indians showing worse disease in the profunda femoris artery and Afro-Caribbeans showing worse disease in the PTA, DPA and MPA. This suggests that environmental factors may play a significant role in the disease process including smoking and dietary factors rather than purely genetics.


Assuntos
Arteriosclerose/etnologia , Extremidade Inferior/irrigação sanguínea , Adulto , Idoso , Idoso de 80 Anos ou mais , Arteriosclerose/diagnóstico por imagem , População Negra/etnologia , Feminino , Humanos , Índia/etnologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Radiografia , Trinidad e Tobago/epidemiologia
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