Buoyancy Driven Microfluidics

It is not surprising that the use of buoyancy as a driving force in microfluidic systems has attracted little or no attention. Buoyant forces are proportional to the volume and do not scale favorably as the device size is reduced. Nevertheless, in certain biotechnological applications, one can produce sufficiently large buoyancy forces to generate fluid motion at velocities on the order of mm/s even in conduits with equivalent diameters of a few hundreds of microns. One example is the thermal polymerase chain reaction (PCR) for DNA amplification. In this process, the reagents’ temperature varies from about 55°C to 94°C. Such large temperature variations can induce significant buoyant forces. Another class of systems that can be driven by buoyant forces is rotating laboratories on a chip (lab on a CD). In such laboratories, large centrifugal accelerations may induce significant buoyant forces even when the temperature variations are relatively small. These temperature variations can be used to propel and control fluid flow.

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A Study of the Efficiency of Modern Domestic Disinfectants in the System of TB Control Activities

Agricultural science and practice ◽

10.15407/agrisp2.02.026 ◽

2015 ◽

Vol 2 (2) ◽

pp. 26-31 ◽

Cited By ~ 3

Author(s):

A. Paliy ◽

A. Zavgorodniy ◽

B. Stegniy ◽

A. Gerilovych

Keyword(s):

Molecular Genetic ◽

Critical Role ◽

Bactericidal Effect ◽

Chain Reaction ◽

Tb Control ◽

Source Of Infection ◽

Polymerase Chain ◽

And Control ◽

Chemical Groups ◽

Test Objects

Due to the absence of elaborated effi cient means for specifi c prevention of bovine tuberculosis, it is ex- tremely important to detect and eliminate the source of infection and to take veterinary and sanitary preven- tive measures. Here the critical role is attributed to disinfection, which breaks the epizootic chain due to the elimination of pathogenic microorganisms in the environment and involves the application of disinfectants of different chemical groups. Aim. To study the tuberculocidal properties of new disinfectants DZPT-2 and FAG against atypical mycobacteria Mycobacterium fortitum and a TB agent Mycobacterium bovis. Methods. The bacteriological and molecular-genetic methods were used. Results. It was determined that DZPT-2 prepara- tion has bactericidal effect on M. fortuitum when used in the concentration of 2.0 % of the active ingredient (AI) when exposed for 5–24 h, while disinfectant FAG has a bactericidal effect in the concentration of 2.0 % when exposed for 24 h. Disinfectant DZPT-2 in the concentration of 2.0 % of the AI, when exposed for 5–24 h, and FAG preparation in the concentration of 2.0 %, when exposed for 24 h, and with the norm of consump- tion rate of 1 cubic decimeter per 1 square meter disinfect the test-objects (batiste, wood, glazed tile, metal, glass), contaminated with the TB agent M. bovis. Conclusions. Disinfecting preparations of DZPT-2 in the concentration of 2.0 % of AI when exposed for 5 h and FAG in the concentration of 2.0 % when exposed for 24 h may be used in the complex of veterinary and sanitary measures to prevent and control TB of farm ani- mals. The possibility of using the polymerase chain reaction as an additional method of estimating tuberculo- cide activity of disinfectants was proven.

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PCR BY THERMAL CONVECTION

Modern Physics Letters B ◽

10.1142/s0217984904007049 ◽

2004 ◽

Vol 18 (16) ◽

pp. 775-784 ◽

Cited By ~ 37

Author(s):

DIETER BRAUN

Keyword(s):

Polymerase Chain Reaction ◽

Thermal Convection ◽

Dna Amplification ◽

Reaction Vessel ◽

Cold Region ◽

Chain Reaction ◽

Heating And Cooling ◽

Highly Sensitive ◽

Specific Amplification ◽

Polymerase Chain

The Polymerase Chain Reaction (PCR) allows for highly sensitive and specific amplification of DNA. It is the backbone of many genetic experiments and tests. Recently, three labs independently uncovered a novel and simple way to perform a PCR reaction. Instead of repetitive heating and cooling, a temperature gradient across the reaction vessel drives thermal convection. By convection, the reaction liquid circulates between hot and cold regions of the chamber. The convection triggers DNA amplification as the DNA melts into two single strands in the hot region and replicates into twice the amount in the cold region. The amplification progresses exponentially as the convection moves on. We review the characteristics of the different approaches and show the benefits and prospects of the method.

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Genetic diversity and phylogeny analysis of Azolla based on DNA amplification by arbitrary primers

Genome ◽

10.1139/g93-092 ◽

1993 ◽

Vol 36 (4) ◽

pp. 686-693 ◽

Cited By ~ 23

Author(s):

Benoit Van Coppenolle ◽

Iwao Watanabe ◽

Charles Van Hove ◽

Gerard Second ◽

Ning Huang ◽

...

Keyword(s):

Principal Component Analysis ◽

Polymerase Chain Reaction ◽

Principal Component ◽

Dna Amplification ◽

Component Analysis ◽

Genetic Distances ◽

Group Method ◽

Chain Reaction ◽

Arbitrary Primers ◽

Polymerase Chain

The polymerase chain reaction was used to amplify random sequences of DNA from 25 accessions of Azolla to evaluate the usefulness of this technique for identification and phylogenetic analysis of this aquatic fern. Accessions were selected to represent all known species within the genus Azolla and to encompass the worldwide distribution of the fern. Primers of 10 nucleotides with 70% G + C content were used to generate randomly amplified polymorphic DNA from the symbiotic Azolla–Anabaena complex. Twenty-two primers were used and each primer gave 4–10 bands of different molecular weights for each accession. Bands were scored as present or absent for each accession and variation among accessions was quantified using Nei's genetic distances. A dendrogram summarizing phenetic relationships among the 25 accessions was generated using the unweighted pair-group method with arithmetic mean. Principal component analysis was also used to evaluate genetic similarities. Three distinct groups were identified: group 1 contains five species, group 2 contains the pinnata species, and group 3 contains the nilotica species. The analysis demonstrates that the major groups of Azolla species can be easily distinguished from one an other and, in addition, that closely related accessions within species can be identified. We further found that using 10 primers, a phylogeny that is essentially the same as that derived from 22 primers can be constructed. Our results suggest that total DNA extracted from the Azolla–Anabaena symbionts is useful for classification and phylogenetic studies of Azolla.Key words: Azolla–Anabaena symbiosis, genetic distances, polymerase chain reaction, principal component analysis.

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HTLV-I-induced lymphoma mimicking Hodgkin's disease. Diagnosis by polymerase chain reaction amplification of specific HTLV-I sequences in tumor DNA

Blood ◽

10.1182/blood.v71.4.1027.1027 ◽

1988 ◽

Vol 71 (4) ◽

pp. 1027-1032 ◽

Cited By ~ 87

Author(s):

DB Duggan ◽

GD Ehrlich ◽

FP Davey ◽

S Kwok ◽

J Sninsky ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Hodgkin's Disease ◽

Polymerase Chain Reaction Amplification ◽

Hodgkin’S Disease ◽

Dna Amplification ◽

Disease Diagnosis ◽

Lymphoproliferative Disease ◽

Enzyme Linked Immunosorbent Assay ◽

Chain Reaction ◽

Polymerase Chain

Abstract A patient with a localized HTLV-I-associated lymphoproliferative disease that was misdiagnosed as Hodgkin's disease is presented. The patient's serum was negative for HTLV-I antibodies by enzyme-linked immunosorbent assay (ELISA), Western blot, and radioimmunoprecipitation. Tumor tissue DNA was negative for HTLV-I by Southern blotting but was positive for distinct HTLV-I sequences when subjected to DNA amplification using the polymerase chain reaction. We conclude that the clinical and pathologic diagnosis of HTLV-I-related lymphoma can be difficult and can be confused with Hodgkin's disease. Extremely sensitive molecular biological techniques may be required to establish a diagnosis of HTLV-I-induced lymphoma.

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How prevalent is Plasmodium malariae in Rondônia, Western Brazilian Amazon?

Revista da Sociedade Brasileira de Medicina Tropical ◽

10.1590/s0037-86822000000500011 ◽

2000 ◽

Vol 33 (5) ◽

pp. 489-492 ◽

Cited By ~ 32

Author(s):

Marisa Torres Vidal Cavasini ◽

Weber Luidi Ribeiro ◽

Fumihiko Kawamoto ◽

Marcelo Urbano Ferreira

Keyword(s):

Polymerase Chain Reaction ◽

Plasmodium Species ◽

Brazilian Amazon ◽

Plasmodium Malariae ◽

Mixed Species ◽

Chain Reaction ◽

Nested Polymerase Chain Reaction ◽

Polymerase Chain ◽

Potential Impact ◽

And Control

We have compared results of Plasmodium species identification obtained with conventional on-site microscopy of Giemsa-stained thick smears (GTS) and a semi-nested polymerase chain reaction (PCR) in 96 malaria patients from Rondônia, Western Brazilian Amazon. Mixed-species infections were detected by PCR in 30% patients, but no such case had been found on GTS. Moreover, P. malariae infections were detected in 9 of 96 patients (10%) by PCR, but were not identified by local microscopists. The potential impact of species misidentification on malaria treatment and control is discussed.

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Methods for identification of causative agents of dangerous and particularly dangerous infections based on the analysis of nucleic acids

Journal of NBC Protection Corps ◽

10.35825/2587-5728-2018-2-4-22-35 ◽

2018 ◽

Vol 2 (4) ◽

pp. 22-35

Keyword(s):

Nucleic Acids ◽

Dna Amplification ◽

Rapid Identification ◽

Chain Reaction ◽

Biological Contamination ◽

Laboratory Facilities ◽

Trained Personnel ◽

Causative Agents ◽

Polymerase Chain ◽

Goals And Objectives

One of the main tasks of the NBC Protection Troops is accurate and rapid identification of infectious disease causative agents in case of establishing the fact of biological contamination. Different methods based on the analysis of nucleic acids are most preferred for this purpose. Most of them are based on DNA amplification by polymerase chain reaction (PCR). The result is detected by electrophoretic separation of amplification products, as well as by registration of endpoint fluorescent signal (FLASH modification) or in real time (PCR-RT). Other methods of DNA amplification, such as ligase chain reaction (LCR) and isothermal amplification, are also applicable in practice. The article also describes some identification methods based on nucleic acid sequencing: multilocus sequence typing (MLST) method, sequencing of individual genes and complete genome sequencing. It is concluded that the choice of identification method should be based on the goals and objectives, laboratory facilities, availability of trained personnel and funding levels. Despite the fact that the most informative are methods based on sequencing nucleotide sequences, their implementation in the field is difficult so far due to technological requirements

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Novel DNA amplification on chromosomes 2p25.3 and 7q11.23 in cholangiocarcinoma identified by arbitrarily primed polymerase chain reaction

Journal of Cancer Research and Clinical Oncology ◽

10.1007/s00432-005-0031-2 ◽

2005 ◽

Vol 131 (12) ◽

pp. 821-828 ◽

Cited By ~ 5

Author(s):

S. Chariyalertsak ◽

T. Khuhaprema ◽

V. Bhudisawasdi ◽

B. Sripa ◽

S. Wongkham ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Dna Amplification ◽

Chain Reaction ◽

Polymerase Chain

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Epidemiology of Blackberry yellow vein associated virus

Plant Disease ◽

10.1094/pdis-01-13-0018-re ◽

2013 ◽

Vol 97 (10) ◽

pp. 1352-1357 ◽

Cited By ~ 28

Author(s):

Bindu Poudel ◽

William M. Wintermantel ◽

Arturo A. Cortez ◽

Thien Ho ◽

Archana Khadgi ◽

...

Keyword(s):

The United States ◽

Yellow Vein ◽

Chain Reaction ◽

Efficient Detection ◽

Blackberry Yellow Vein Disease ◽

Polymerase Chain ◽

Multiple Levels ◽

And Control ◽

Trialeurodes Abutilonea ◽

Vein Disease

Blackberry yellow vein disease is one of the most important diseases of blackberry in the United States. Several viruses are found associated with the symptomology but Blackberry yellow vein associated virus (BYVaV) appears to be the most prevalent of all, leading to the need for a better understanding of its epidemiology. Efficient detection protocols were developed using end-point and quantitative reverse-transcription polymerase chain reaction. A multi-state survey was performed on wild and cultivated blackberry to assess the geographical distribution of the virus. Two whitefly species, Trialeurodes abutilonea and T. vaporariorum, were identified as vectors and 25 plant species were tested as potential BYVaV hosts. The information obtained in this study can be used at multiple levels to better understand and control blackberry yellow vein disease.

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