Direct immobilization of DNA probes on non-modified plastics by UV irradiation and integration in microfluidic devices for rapid bioassay

DNA microarrays have become one of the most powerful tools in the field of genomics and medical diagnosis. Recently, there has been increased interest in combining microfluidics with microarrays since this approach offers advantages in terms of portability, reduced analysis time, low consumption of reagents, and increased system integration. Polymers are widely used for microfluidic systems, but fabrication of microarrays on such materials often requires complicated chemical surface modifications, which hinders the integration of microarrays into microfluidic systems. In this paper, we demonstrate that simple UV irradiation can be used to directly immobilize poly(T)poly(C)-tagged DNA oligonucleotide probes on many different types of plastics without any surface modification. On average, five- and fourfold improvement in immobilization and hybridization efficiency have been achieved compared to surface-modified slides with aminated DNA probes. Moreover, the TC tag only costs 30% of the commonly used amino group modifications. Using this microarray fabrication technique, a portable cyclic olefin copolymer biochip containing eight individually addressable microfluidic channels was developed and used for rapid and parallel identification of Avian Influenza Virus by DNA hybridization. The one-step, cost-effective DNA-linking method on non-modified polymers significantly simplifies microarray fabrication procedures and permits great flexibility to plastic material selection, thus making it convenient to integrate microarrays into plastic microfluidic systems

Synergism between particle-based multiplexing and microfluidics technologies may bring diagnostics closer to the patient

In the field of medical diagnostics there is a growing need for inexpensive, accurate, and quick high-throughput assays. On the one hand, recent progress in microfluidics technologies is expected to strongly support the development of miniaturized analytical devices, which will speed up (bio)analytical assays. On the other hand, a higher throughput can be obtained by the simultaneous screening of one sample for multiple targets (multiplexing) by means of encoded particle-based assays. Multiplexing at the macro level is now common in research labs and is expected to become part of clinical diagnostics. This review aims to debate on the “added value” we can expect from (bio)analysis with particles in microfluidic devices. Technologies to (a) decode, (b) analyze, and (c) manipulate the particles are described. Special emphasis is placed on the challenges of integrating currently existing detection platforms for encoded microparticles into microdevices and on promising microtechnologies that could be used to down-scale the detection units in order to obtain compact miniaturized particle-based multiplexing platforms

EFFECT OF COVI-SOUP ON CD4 CELL COUNT AND HAEMOGLOBIN AMONG PATIENTS WITH DIABETES TYPE II AND HYPERTENSION IN KAKAMEGA COUNTY, KENYA: A RANDOMIZED CONTROL TRIAL

Type II diabetes mellitus (DM) and hypertension (HTN) diseases are part of the world’s challenges in achieving sustainable development goals. Cases of type II diabetes mellitus and hypertension diseases in low and middle-income countries are becoming a concern. Type II diabetes mellitus is an inflammatory disease. When there is inflammation the immune system is triggered and haemoglobin level is affected. While there have been numerous strategies to address the issue, these efforts have not been sufficient to guarantee a reduction in disease severity. This was an experimental study conducted in Kakamega County, Kenya. It employed a randomized control trial approach, with two groups: treatment and control. Systematic random sampling was used in identifying participants and simple randomization was used to allocate the respondent to the intervention groups. Sample sizes of 34 (treatment group) and 30 (control group) were used to produce quantitative data. This study evaluated the effect of COVI-soup on haemoglobin (Hb) and cluster of differentiation 4 (CD4) cell count of patients living with both type II diabetes mellitus and hypertension. The treatment group received COVI-soup (a soup composed of butternut squash, ginger, garlic, sunflower pepper, chia seeds and turmeric) while the control group was on a rice soup. Statistical Packages for Social Science (SPSS) version 20 was used in the data analysis. A paired student t-test was used to determine the effect of COVI-soup on Hb and CD4 cell count. There was a positive effect in CD4 cell count in the treatment group (P =0.001) whereas there was no significant effect in the control group (P =0.267). The mean change in CD4 cell count in the treatment group was 97 cells/ul and in the control 75 cells/ul. There was a positive effect (increase) on hemoglobin levels in the treatment group (p=0.0001) whereas there was no significant effect in the control group (p =0.126). The hemoglobin mean change in the treatment group was 3.9 g/dl and in the control 0.5 g/dl. Therefore, COVI-soup had a positive effect on hemoglobin and CD4 cell count levels among patients with both hypertension and type II diabetes mellitus

EFFECT OF COVI-SOUP ON CD4 CELL COUNT AND HAEMOGLOBIN AMONG PATIENTS WITH DIABETES TYPE II AND HYPERTENSION IN KAKAMEGA COUNTY, KENYA: A RANDOMIZED CONTROL TRIAL

Type II diabetes mellitus (DM) and hypertension (HTN) diseases are part of the world’s challenges in achieving sustainable development goals. Cases of type II diabetes mellitus and hypertension diseases in low and middle-income countries are becoming a concern. Type II diabetes mellitus is an inflammatory disease. When there is inflammation the immune system is triggered and haemoglobin level is affected. While there have been numerous strategies to address the issue, these efforts have not been sufficient to guarantee a reduction in disease severity. This was an experimental study conducted in Kakamega County, Kenya. It employed a randomized control trial approach, with two groups: treatment and control. Systematic random sampling was used in identifying participants and simple randomization was used to allocate the respondent to the intervention groups. Sample sizes of 34 (treatment group) and 30 (control group) were used to produce quantitative data. This study evaluated the effect of COVI-soup on haemoglobin (Hb) and cluster of differentiation 4 (CD4) cell count of patients living with both type II diabetes mellitus and hypertension. The treatment group received COVI-soup (a soup composed of butternut squash, ginger, garlic, sunflower pepper, chia seeds and turmeric) while the control group was on a rice soup. Statistical Packages for Social Science (SPSS) version 20 was used in the data analysis. A paired student t-test was used to determine the effect of COVI-soup on Hb and CD4 cell count. There was a positive effect in CD4 cell count in the treatment group (P =0.001) whereas there was no significant effect in the control group (P =0.267). The mean change in CD4 cell count in the treatment group was 97 cells/ul and in the control 75 cells/ul. There was a positive effect (increase) on hemoglobin levels in the treatment group (p=0.0001) whereas there was no significant effect in the control group (p =0.126). The hemoglobin mean change in the treatment group was 3.9 g/dl and in the control 0.5 g/dl. Therefore, COVI-soup had a positive effect on hemoglobin and CD4 cell count levels among patients with both hypertension and type II diabetes mellitus

Fabrication of DNA microarrays onto polymer substrates using UV modification protocols with integration into microfluidic platforms for the sensing of low-abundant DNA point mutations

We describe the microfabrication and operational characteristics of a simple flow-through biochip sensor capable of detecting low abundant point mutations in K-ras oncogenes from genomic DNA, which carry high diagnostic value for colorectal cancers. The biochip consisted of an allele-specific ligase detection reaction (LDR) coupled to a universal array for interrogating multiple mutations simultaneously from a clinical sample. The integrated sensing platform was micro-manufactured from two different polymers, polycarbonate, PC, which was used for the LDRs, and poly(methyl methacrylate), PMMA, which was used to build the microarray. Passive elements were hot embossed into the PC and PMMA microchips and then, the chips assembled into a three-dimensional architecture with the interconnect fabricated from an elastomer, poly(dimethylsiloxane), PDMS, to produce a leak-free connection between the biochips. The array in PMMA was produced using a photomodification process, which involved three steps; (1) UV (254 nm) exposure of the polymer surface; (2) EDC coupling of amine-terminated oligonucleotide probes to the surface (via an amide bond) and; (3) washing of the surface. The LDR/hybridization flow-through biochip performed the entire assay at a relatively fast processing speed: 6.5 min for on-chip LDR, 10 min for washing, and 2.6 min for fluorescence scanning (total processing time = 19.1 min) and could screen multiple mutations simultaneously for high throughput applications at a level of one mutant sequence in 100 wild-type sequences. © 2005 Elsevier Inc. All rights reserved

The AGRICAB project: developing increased earth observation capacity for better agriculture and forestry management in Africa

This paper gives an overview of the upcoming efforts and activities in the recently started AGRICAB project ‘A Framework for enhancing earth observation capacity for agriculture and forest management in Africa as a contribution to GEOSS’, which main focus is to integrate European and African research capacity and advances in the use of Earth observation technology for agriculture and forestry. One of the key challenges in the future is to enhance scientific and remote sensing capacity in Africa to enable African institutes to independently monitor and generate information on their natural resources to adequately support management and policy actions. Apart from the sustained provision of (derived) EO data, the project aims at a continued and better exploitation of and access to satellite data. Twinning partnerships between African and European institutes are being set up in order to integrate EO and predictive modeling in agriculture and forest management in different themes: yield forecasting for food crops, early warning and agricultural mapping of food crops, agricultural statistics, livestock and rangeland monitoring, and forest and forest fire monitoring. For more information: www.agricab.info and [email protected]