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Tariq Aslam

Publications and source records attributed to Tariq Aslam.

8 recordsLinked to original sources
PubMed2026

Comparative Responses of Invasive and Native Plant Species to Combined Cd and Microplastic Pollution.

The co-occurrence of heavy metal contamination and biodegradable microplastic (polylactic acid, PLA) pollution poses increasing risks to terrestrial plant communities and soil functioning, yet species-specific responses to combined stress remain poorly understood. Cd and microplastics frequently co-occur in agricultural soils, where microplastics can alter cadmium mobility, bioavailability, and transport pathways, potentially modifying metal toxicity and plant stress responses compared with single-pollutant exposure. We investigated the responses of the invasive Bidens pilosa and the native Solanum nigrum grown in monoculture and mixed culture under combined cadmium (Cd) and biodegradable microplastic (PLA) stress by integrating plant growth, photosynthetic performance, oxidative physiology, and rhizosphere biochemical processes. Combined Cd-MP exposure markedly reduced plant growth, chlorophyll content (SPAD), photosystem II efficiency (Fv/Fm), nitrogen accumulation, biomass production, and rhizosphere enzyme activities associated with carbon, nitrogen, and phosphorus cycling. However, B. pilosa maintained greater physiological stability under stress, characterized by higher antioxidant enzyme activities (SOD, CAT, POD), lower reactive oxygen species (H2O2, O2˙-) accumulation, and reduced lipid peroxidation (MDA), whereas S. nigrum exhibited stronger oxidative damage and functional impairment. Multivariate analyses further revealed that root antioxidant capacity was closely associated with rhizosphere microbial enzyme activity, suggesting a root-centered regulatory mechanism linking plant stress tolerance to soil functioning. Overall, the invasive species showed greater tolerance to combined contamination and maintained relatively higher rhizosphere functional activity than the native species, indicating that multi-pollutant stress may alter competitive interactions between invasive and native plants in contaminated environments.

Cadmium↗
PubMed2006

Asymmetry of retinal arteriolar branch widths at junctions affects ability of formulae to predict trunk arteriolar widths.

PURPOSE: To describe a revised formula for the estimation of retinal trunk arteriole widths from their respective arteriolar branch widths that improves the summarizing of retinal arteriolar diameters. METHODS: A group of young, healthy individuals underwent retinal photography and arteriolar and venular branching points were identified. Vessel widths of the vessel trunks and their branches were determined. The relationship between the branching coefficient (BC; quotient of the area of the branch and trunk vessels) and the asymmetry index (AI) of the vessel branches was explored. The result was used to formulate a new BC. To test the new BC, a second group of young, healthy individuals also underwent retinal photography. Arteriolar branching points were identified, and the trunk and branch arteriolar widths were recorded. This "revised" BC was compared against the gold standard of the BC as a constant value (1.28), as well as a theoretical formula for the BC that includes the angle between the two vessel branches. RESULTS: The BC of arterioles (but not venules) related to the AI (R = 0.275, P = 0.0001; BC arterioles = 0.78 +/- 0.63 . AI). In the second group, the mean arteriolar trunk diameter was 15.56 pixels. The linear regression model for the arteriolar BC was superior to the BC constant of 1.28 (mean difference between estimated and calculated trunk vessel width was 2.16 vs. 2.23 pixels, respectively). The model based on the angle between the branch arterioles was the least accurate (3.43 pixels). CONCLUSIONS: A revised formula has been devised for the arteriolar BC using a linear regression model that incorporates its relationship to the AI. Further studies using this refined formula to calculate the BC are needed to determine whether it improves the ability to detect smaller associations between the retinal vascular network and cardiovascular disease.

Adult↗
PubMed2005

Retinal vascular image analysis as a potential screening tool for cerebrovascular disease: a rationale based on homology between cerebral and retinal microvasculatures.

The retinal and cerebral microvasculatures share many morphological and physiological properties. Assessment of the cerebral microvasculature requires highly specialized and expensive techniques. The potential for using non-invasive clinical assessment of the retinal microvasculature as a marker of the state of the cerebrovasculature offers clear advantages, owing to the ease with which the retinal vasculature can be directly visualized in vivo and photographed due to its essential two-dimensional nature. The use of retinal digital image analysis is becoming increasingly common, and offers new techniques to analyse different aspects of retinal vascular topography, including retinal vascular widths, geometrical attributes at vessel bifurcations and vessel tracking. Being predominantly automated and objective, these techniques offer an exciting opportunity to study the potential to identify retinal microvascular abnormalities as markers of cerebrovascular pathology. In this review, we describe the anatomical and physiological homology between the retinal and cerebral microvasculatures. We review the evidence that retinal microvascular changes occur in cerebrovascular disease and review current retinal image analysis tools that may allow us to use different aspects of the retinal microvasculature as potential markers for the state of the cerebral microvasculature.

Aging↗