On-chip absorption spectroscopy enabled by graded index fiber tips.

This paper describes the design and characterization of miniaturized optofluidic devices for sensing based on integrating collimating optical fibers with custom microfluidic chips. The use of collimating graded-index fiber (GIF) tips allows for effective fiber-channel-fiber interfaces to be realized when compared with using highly-divergent standard single-mode fiber (SMF). The reduction in both beam divergence and insertion losses for the GIF configuration compared with SMF was characterized for a 10.0 mm channel. Absorption spectroscopy was demonstrated on chip for the measurement of red color dye (Ponceau 4R), and the detection of thiocyanate in water and artificial human saliva. The proposed optofluidic setup allows for absorption spectroscopy measurements to be performed with only 200 µL of solution which is an order of magnitude smaller than for standard cuvettes but provides a comparable sensitivity. The approach could be integrated into a lab-on-a-chip system that is compact and does not require free-space optics to perform absorption spectroscopy.

Bioaccumulation of pesticide contaminants in tissue matrices of dogs suffering from malignant canine mammary tumors in Punjab, India.

The unprecedented application of pesticides in Punjab, India during green revolution has lead to an environmental crisis due to the accumulation of persistent organic and pesticide pollutants in the environment and biota of this region. The present study aimed at estimating the abundance of pesticide contaminants in three biological matrices of 36 dogs suffering from malignant canine mammary tumor (mCMT) and 6 tumor free control dogs from Punjab, India. Presence of individual and total pesticides in canine biological samples, age and bodyweight of canine patients was assessed as a potential risk factor for mCMT using logistic regression analysis. Chi-square test was employed to determine tissue-specific accumulations of individual pesticides. Spearman's correlation coefficient was estimated to determine the association between the levels of total pesticides in different tissue matrices and with age and bodyweight of mCMT cases. Gas chromatography-ECD analysis of serum, mammary tissue and adjoining mammary adipose tissue revealed fourteen different pesticides including γ-HCH, α-HCH, dieldrin, aldrin, heptachlor, butachlor, p,p-DDT, o,p-DDT, p,p-DDD, p,p-DDE, L-cyhalothrin, permethrin, fipronil, and fenitrothion. Heptachlor, γ-HCH, aldrin and p,p-DDT were more frequently detected, whereas, p,p-DDE and o,p-DDT were the least common. Differential accumulation of pesticides in tissue matrices, particularly between serum and mammary tissue/adipose tissue was observed. We could not find any association between the total pesticide concentrations among serum, mammary tissue and mammary adipose tissue in mCMT cases. We found that the odds for individual pesticide for serum, mammary tissue and adipose tissue were associated with high uncertainties; however, the total pesticide concentration in mammary tissue was near non-significantly associated with higher risk of mCMT with low uncertainty. Statistically non-significant higher odds of CMT occurrence with increase in age was noticed No association between the concentration of total pesticides in different matrices and age and bodyweight of canine subjects was found.

Antioxidant status in oral subchronic toxicity of fipronil and fluoride co-exposure in buffalo calves.

The effects of fipronil and fluoride co-exposure were investigated on antioxidant status of buffalo calves. A total of 24 healthy male buffalo calves divided into 4 groups were treated for 98 consecutive days. Group I, receiving no treatment, served as the control. Animals of groups II and III were orally administered with fipronil at the dosage of 0.5 mg/kg/day and sodium fluoride (NaF) at the dosage of 6.67 mg/kg/day, respectively, for 98 days. Group IV was coadministered with fipronil and NaF at the same dosages as groups II and III. Administration of fipronil alone produced significant elevation in lipid peroxidation (LPO) and decrease in the levels of nonenzymatic antioxidant glutathione (GSH). However, it did not produce any significant effect on the activities of enzymatic antioxidants including glutathione peroxidase (GPx), catalase (CAT), and superoxide dismutase (SOD). NaF exposure led to enhanced oxidative stress as shown by significant increase in the LPO and SOD activities while GPx and CAT activities and GSH levels were significantly decreased. Co-exposure to fipronil and NaF showed additive effects on LPO, GPx activity, and GSH levels.

Evaluation of lipid peroxidation and antioxidant status on fenvalerate, nitrate and their co-exposure in Bubalus bubalis.

The toxic effects of pesticides and minerals have been explored in different species, but still there is paucity of information regarding their combined toxicological effects. The present investigation reports oxidative stress induced by oral subacute exposure to fenvalerate (1 mg/kg) and sodium nitrate (20 mg/kg) alone, as well as in combination daily for 21 days in buffalo calves. Fenvalerate exposure produced significant elevation in lipid peroxidation (LPO), glutathione peroxidase (GPx), while it produced significant decline in blood glutathione (GSH) levels, superoxide dismutase (SOD) and catalase (CAT). No significant alteration was evidenced in nitric oxide (NOx) levels. Oral exposure to sodium nitrate produced significant inclination in LPO and NOx, while on the other hand significant depreciation in SOD and CAT with no significant change in GPx activity. Combined exposure to fenvalerate and sodium nitrate produced severe effects with an appreciably more prominent elevation in extent of LPO and decline in blood GSH levels.

Haematological alterations induced by oral subacute exposure to fenvalerate, nitrate and their combination in domestic buffalo, Bubalus bubalis.

The present study investigated haematological alterations induced by oral subacute exposure to fenvalerate, nitrate and their combination in the domestic buffalo, Bubalus bubalis. Fenvalerate exposure produced significant declines in haemoglobin (Hb), total leukocyte count (TLC), total erythrocyte count (TEC) and mean corpuscular haemoglobin concentration (MCHC), and a corresponding elevation in mean corpuscular volume (MCV). Following oral exposure to sodium nitrate, significant declines in blood Hb, TLC, TEC, MCH and MCHC, and a significant elevation in MCV occurred. Combined exposure to fenvalerate and sodium nitrate produced severe effects with an appreciably more prominent decline in Hb, TLC, TEC and MCHC and a significant elevation in MCV. The percentage of methaemoglobin was observed to follow an elevating trend in animals exposed to sodium nitrate alone (0.69 %-13.8 %) and in combination with fenvalerate (0.75 %-13.7 %).

Association of frailty and physical function in patients with non-dialysis CKD: a systematic review.

BACKGROUND: Frailty is a condition characterized by a decline in physical function and functional capacity. Common symptoms of frailty, such as weakness and exhaustion, are prevalent in patients with chronic kidney disease (CKD). The increased vulnerability of frail patients with coexisting CKD may place them at a heightened risk of encountering additional health complications. The purpose of this systematic review was to explore the link between frailty, CKD and clinical outcomes. METHODS: We searched for cross sectional and prospective studies in the general population and in the CKD population indexed in EMBASE, Pubmed, Web of Science, CINAHL, Cochrane and Ageline examining the association between frailty and CKD and those relating frailty in patients with CKD to clinical outcomes. RESULTS: We screened 5,066 abstracts and retrieved 108 studies for full text review. We identified 7 studies associating frailty or physical function to CKD. From the 7 studies, we identified only two studies that related frailty in patients with CKD to a clinical outcome. CKD was consistently associated with increasing frailty or reduced physical function [odds ratios (OR) 1.30 to 3.12]. In patients with CKD, frailty was associated with a greater than two-fold higher risk of dialysis and/or death [OR from 2.0 to 5.88]. CONCLUSIONS: CKD is associated with a higher risk of frailty or diminished physical function. Furthermore, the presence of frailty in patients with CKD may lead to a higher risk of mortality. Further research must be conducted to understand the mechanisms of frailty in CKD and to confirm its association with clinical outcomes.

Biochemical alterations induced by oral subchronic exposure to fipronil, fluoride and their combination in buffalo calves.

The effects of various pesticides and minerals on biochemical parameters have been explored in different species, but hardly any data exist regarding the combined toxicological effect of pesticides and minerals on these parameters in animals. The present study investigated the effects of fipronil and fluoride co-exposure on biochemical parameters in buffalo calves. Twenty-four healthy male buffalo calves divided into four groups were treated for 98 consecutive days. Group I, receiving no treatment served as the control. Animals of groups II and III were orally administered with fipronil @ 0.5mg/kg/day and sodium fluoride (NaF) @ 6.67 mg/kg/day, respectively, for 98 days. An additional group IV was co-administered fipronil and NaF at the same dosages as groups II and III. Administration of fipronil alone produced mild toxic signs, significant elevation in plasma proteins, blood glucose, blood urea nitrogen (BUN) and significant decline in the plasma cholesterol levels. NaF exposure produced toxic signs specifically of muscle weakness and brown and black discoloration of teeth. Significant elevation was seen in whole blood cholinesterase, BUN and creatinine levels. However, it produced significant decline in blood glucose, cholesterol and plasma protein levels. Combined exposure to fipronil and sodium fluoride produced toxic signs with greater intensity while biochemical alterations produced were similar to those that were produced by their individual exposures.