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1.
Parasitol Res ; 123(7): 282, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39037590

RESUMEN

This study examined the pattern of resistance to widely applied synthetic pyrethroids, i.e., cypermethrin and deltamethrin, against larvae of Rhipicephalus microplus ticks sampled from Marathwada region in Maharashtra, India. The study also examined the role of α- and ß-esterases and glutathione-S-transferase (GST) in resistance development. All eight R. microplus isolates tested were resistant to deltamethrin (RL IV), having RR50 values from 6.88 to 131.26. LPT analysis exhibited the resistance level II deltamethrin resistance in Beed and Hingoli, III in Dharashiv, and IV in Sambhajinagar, Parbhani, Latur, Jalna, and Nanded isolates. The LIT analysis showed that Dharashiv field isolates had the lowest LC50 value of 229.09 ppm against cypermethrin, while Sambhajinagar field isolates had the highest at 489.78 ppm. The RR50 ranged from 1145.45 to 2448.9. Seven isolates were level I resistant to cypermethrin while the Jalna isolate was level II resistant. In larvae treated with deltamethrin and cypermethrin, the activity of α- and ß-esterase enzymes increased significantly compared to control groups. The enzyme ratios in treated larvae ranged from 0.7533 to 1.7023 for α-esterase and 0.7434 to 3.2054 for ß-esterase. The Hingoli isolate treated with cypermethrin exhibited the highest α-esterase activity (903.261), whereas Sambhajinagar isolate had the highest GST enzyme ratio (2.8224) after deltamethrin exposure. When exposed to cypermethrin, the Hingoli isolate showed the highest GST enzyme ratio, 2.0832. The present study provides the current resistance status in tick populations from Marathwada region indicating deltamethrin and cypermethrin to be ineffective for tick control. The results also suggest that SP compounds should be regulated in this region and alternative control strategies should be introduced.


Asunto(s)
Acaricidas , Glutatión Transferasa , Larva , Nitrilos , Piretrinas , Rhipicephalus , Animales , Piretrinas/farmacología , India , Rhipicephalus/efectos de los fármacos , Rhipicephalus/enzimología , Nitrilos/farmacología , Larva/efectos de los fármacos , Glutatión Transferasa/metabolismo , Acaricidas/farmacología , Esterasas/metabolismo , Resistencia a los Insecticidas , Resistencia a Medicamentos
2.
Adv Exp Med Biol ; 1395: 9-15, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36527606

RESUMEN

Broadband near-infrared spectroscopy (bNIRS) has the potential to provide non-invasive measures of cerebral haemodynamic changes alongside changes in cellular oxygen utilisation through the measurement of mitochondrial enzyme cytochrome-c-oxidase (oxCCO). It therefore provides the opportunity to explore brain function and specialisation, which remains largely unexplored in infancy. We used bNIRS to measure changes in haemodynamics and changes in oxCCO in 4-to-7-month-old infants over the occipital and right temporal and parietal cortices in response to social and non-social visual and auditory stimuli. Changes in concentration of oxygenated-haemoglobin (Δ[HbO2]), deoxygenated haemoglobin (Δ[HHb]) and change in the oxidation state of oxCCO (Δ[oxCCO]) were calculated using changes in attenuation of light at 120 wavelengths between 780 and900 nm, using the UCLn algorithm. For 4 infants, the attenuation changes in a subset of wavelengths were used to perform image reconstruction, in an age-matched infant model, for channels over the right parietal and temporal cortices, using a multispectral approach which allows direct reconstruction of concentration change data. The volumetric reconstructed images were mapped onto the cortical surface to visualise the reconstructed changes in concentration of HbO2 and HHb and changes in metabolism for both social and non-social stimuli. Spatially localised activation was observed for Δ[oxCCO] and Δ[HbO2] over the temporo-parietal region, in response to the social stimulus. This study provides the first reconstructed images of changes in metabolism in healthy, awake infants.


Asunto(s)
Encéfalo , Espectroscopía Infrarroja Corta , Lactante , Humanos , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Espectroscopía Infrarroja Corta/métodos , Oxihemoglobinas/metabolismo , Complejo IV de Transporte de Electrones/metabolismo , Metabolismo Energético , Hemoglobinas/metabolismo
3.
Sci Rep ; 11(1): 3977, 2021 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-33597576

RESUMEN

With the rapid growth of optical-based neuroimaging to explore human brain functioning, our research group has been developing broadband Near Infrared Spectroscopy (bNIRS) instruments, a technological extension to functional Near Infrared Spectroscopy (fNIRS). bNIRS has the unique capacity of monitoring brain haemodynamics/oxygenation (measuring oxygenated and deoxygenated haemoglobin), and metabolism (measuring the changes in the redox state of cytochrome-c-oxidase). When combined with electroencephalography (EEG), bNIRS provides a unique neuromonitoring platform to explore neurovascular coupling mechanisms. In this paper, we present a novel pipeline for the integrated analysis of bNIRS and EEG signals, and demonstrate its use on multi-channel bNIRS data recorded with concurrent EEG on healthy adults during a visual stimulation task. We introduce the use of the Finite Impulse Response functions within the General Linear Model for bNIRS and show its feasibility to statistically localize the haemodynamic and metabolic activity in the occipital cortex. Moreover, our results suggest that the fusion of haemodynamic and metabolic measures unveils additional information on brain functioning over haemodynamic imaging alone. The cross-correlation-based analysis of interrelationships between electrical (EEG) and haemodynamic/metabolic (bNIRS) activity revealed that the bNIRS metabolic signal offers a unique marker of brain activity, being more closely coupled to the neuronal EEG response.


Asunto(s)
Acoplamiento Neurovascular/fisiología , Encéfalo , Mapeo Encefálico , Complejo IV de Transporte de Electrones/metabolismo , Hemodinámica , Humanos , Modelos Estadísticos , Neuroimagen , Espectroscopía Infrarroja Corta
4.
Adv Exp Med Biol ; 1072: 7-12, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30178316

RESUMEN

A novel multi-wavelength broadband near infrared spectroscopy (NIRS) system has been employed to simultaneously measure haemodynamic changes alongside changes in cellular oxygen utilization by measurement of oxidation state of mitochondrial enzyme cytochrome-c-oxidase (oxCCO). The aim of this study was to investigate the role of oxCCO in neural responses to functional activation in infants. Studies were performed using a NIRS broadband system in 33 typically developing infants aged between 4 and 6 months. Responses were recorded over the right temporal lobe while infants were presented with engaging videos containing social and non-social content. Changes in the concentration of oxyhaemoglobin (Δ[HbO2]), deoxyhaemoglobin (Δ[HHb]) and Δ[oxCCO] were calculated using changes in attenuation of light at 120 wavelengths between 780 and 900 nm using the UCLn algorithm. The algorithm was also used to fit (a) HbO2 and HHb spectra (2 component fit) and (b) HbO2, HHb and oxCCO (3 component fit) to the change in attenuation occurring within an experimental block in different participants. Residuals resulting from these two fits were compared with oxidized-minus reduced CCO spectrum, calculated using the CCO specific extinction coefficient. A significant increase in oxCCO was found in response to the social stimuli (maximum increase 0.238 ± 0.13 µM). Residuals analysis showed that the best fits were achieved when oxCCO was included as a tissue chromophore. These results are the first reported significant change in oxCCO to stimulus-evoked activation in infants and may reveal vital information about oxygen metabolism during functional activation in the developing human brain.


Asunto(s)
Encéfalo/metabolismo , Complejo IV de Transporte de Electrones/metabolismo , Consumo de Oxígeno/fisiología , Oxígeno/metabolismo , Espectroscopía Infrarroja Corta/métodos , Humanos , Lactante
5.
ScientificWorldJournal ; 2014: 620868, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25133249

RESUMEN

A wide interest has been observed to find a low power and area efficient hardware design of discrete cosine transform (DCT) algorithm. This research work proposed a novel Common Subexpression Elimination (CSE) based pipelined architecture for DCT, aimed at reproducing the cost metrics of power and area while maintaining high speed and accuracy in DCT applications. The proposed design combines the techniques of Canonical Signed Digit (CSD) representation and CSE to implement the multiplier-less method for fixed constant multiplication of DCT coefficients. Furthermore, symmetry in the DCT coefficient matrix is used with CSE to further decrease the number of arithmetic operations. This architecture needs a single-port memory to feed the inputs instead of multiport memory, which leads to reduction of the hardware cost and area. From the analysis of experimental results and performance comparisons, it is observed that the proposed scheme uses minimum logic utilizing mere 340 slices and 22 adders. Moreover, this design meets the real time constraints of different video/image coders and peak-signal-to-noise-ratio (PSNR) requirements. Furthermore, the proposed technique has significant advantages over recent well-known methods along with accuracy in terms of power reduction, silicon area usage, and maximum operating frequency by 41%, 15%, and 15%, respectively.


Asunto(s)
Algoritmos , Compresión de Datos/métodos , Fotograbar/métodos , Grabación en Video/métodos
6.
Parkinsonism Relat Disord ; 8(4): 277-84, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12039423

RESUMEN

BACKGROUND: Autonomic dysfunction occurs in Parkinson's disease (PD), but few studies have addressed it in a comprehensive manner. METHODS: Autonomic symptoms were evaluated by a questionnaire in sixty-eight subjects (44 patients and 24 controls). RESULTS: PD patients experienced higher frequency and severity of autonomic dysfunction. When all autonomic symptoms were pooled into an aggregate score, differences between patients and controls were highly statistically significant (p<0.0001). 'Increased salivation', 'frequency of dysphagia', decreased 'BM (bowel movement) frequency', i.e. constipation, and 'orthostatic dizziness' were more frequent in PD patients (p<0.05). A prediction model to determine the predictors of autonomic dysfunction was unsuccessful. CONCLUSION: Differences in the prevalence of autonomic symptoms in PD and non-parkinsonian controls are apparent from this study.


Asunto(s)
Enfermedades del Sistema Nervioso Autónomo/etiología , Enfermedad de Parkinson/complicaciones , Anciano , Enfermedades del Sistema Nervioso Autónomo/epidemiología , Enfermedades del Sistema Nervioso Autónomo/fisiopatología , Femenino , Enfermedades Gastrointestinales/epidemiología , Enfermedades Gastrointestinales/etiología , Encuestas Epidemiológicas , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/fisiopatología , Prevalencia , Valores de Referencia , Análisis de Regresión , Índice de Severidad de la Enfermedad
7.
Muscle Nerve ; 21(5): 650-2, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9572247

RESUMEN

Severe hypophosphatemia has rarely been reported as a cause of acute paralysis. We present the clinical and electrophysiological findings on a patient who developed quadriparesis following several surgeries for complicated cholecystectomy. The paralysis was most likely the result of severe hypophosphatemia causing a neuropathy which improved readily after proper phosphate replacement. The possible pathogenic mechanisms of hypophosphatemic neuropathy are discussed.


Asunto(s)
Hipofosfatemia/complicaciones , Polirradiculoneuropatía/etiología , Cuadriplejía/etiología , Colecistectomía , Electrofisiología , Femenino , Humanos , Hipofosfatemia/tratamiento farmacológico , Persona de Mediana Edad , Nutrición Parenteral , Fosfatos/administración & dosificación , Fosfatos/uso terapéutico , Polirradiculoneuropatía/fisiopatología , Complicaciones Posoperatorias , Cuadriplejía/fisiopatología
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