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Parasitic infections, including avian chronic haemosporidian infection, have been proven to be a major selection force affecting birds on a global scale including closely related bird species. To date, there has been limited information about haemosporidian infections in the red junglefowl (Gallus gallus) as compared to the domestic chicken (G. gallus domesticus). In this study, we collected blood samples of 39 wild red junglefowls and 122 domestic chickens to test for the presence of haemosporidian infections and various parasitic lineages. The PCR product of positive samples was sequenced, and their lineage was identified using the GenBank database. The result showed that all sampled red junglefowls tested positive for haemosporidian infection with 100% of parasite prevalence, while 104 domestic chickens tested positive (85%). Furthermore, parasite lineages were more diverse in red junglefowls compared to domestic chickens. We recommend that further research should be conducted on more populations of wild red junglefowls in comparison to the domestic chickens to ascertain the prevalence of haemosporidian parasites in association with vectors and other risk factors.

Reportar una experiencia piloto de atención por telemedicina en la especialidad de oftalmología, en el periodo de confinamiento por la pandemia por COVID-19.

Analysis of the vibration responses of a fruit has been suggested as a non-destructive measure of its elastic properties (firmness). In this study, 'Huang gua' melons were excited using three types of balls (wooden, steel and rubber) and the vibration was detected by an accelerometer. The modulus of elasticity of the inner, middle and outer portions of melon flesh were determined using flat plate compression of cylindrical samples. The Instron device was used to measure the static elastic modulus and the Finite Element (FE) technique was used to determine the optimum location of the excitation on fruits. Four types of mode shapes were found: torsional or flexural mode shape, first-type of longitudinal mode shape, second-type of longitudinal mode shape and breathing mode shape. The results from FM simulation were in good agreement with experimental results and there was good correlation between the fruit firmness and its resonant frequency.

Adenoviral vectors are attractive for the delivery of transgenes into mammalian cells because of their efficient transduction, high titer, and stability. The major concerns with using E1-deleted adenoviral vectors in gene therapy are the pathogenic potential of the virus backbone and the leaky viral protein synthesis that leads to host immune responses and a short duration of transgene expression. Helper-dependent (HD) adenoviral vectors that are devoid of all viral protein-coding sequences have significantly increased the safety and reduced the immunogenicity of these vectors. Currently available HD vectors depend on an E1-deleted adenovirus as a helper to provide viral proteins in trans. As a consequence, contamination with helper virus cannot be avoided in the HD vector preparation though it can be decreased to 0.01% using a Cre/loxP mechanism. Since the presence of E1-deleted helper virus may have substantial unwanted effects, we have developed a new Cre-expressing cell line based on an E1- and E2a-complementing cell. This new cell line can efficiently cleave the packaging region in the helper virus genome. We have also developed an E1 and E2a double-deleted helper virus. By using the CreE cell with the helper virus deleted in both the E1 and the E2a genes it may be possible to further improve the safety of the vectors.Molecular Therapy (2001) 3, 613–622; doi: 10.1006/mthe.2001.0288

Vaccination against Helicobacter pylori using DNA sequences encoding Urease A and B subunits was compared to immunization with urease antigen and MTP-PE in a liposome formulation. To determine the effectiveness of a vaccine against H. pylori in a mouse model it is essential to quantify the number of H. pylori remaining in the stomachs following challenge with an inoculum of live bacteria. Culture assays and enzymatic assays produce inconsistent results often unsuitable to conclude if vaccine candidates are protective. To overcome this problem, we developed two assays: 1) a competitive quantitative PCR using a colorimetric readout and 2) a non-competitive direct quantitative PCR using a highly sensitive bioluminescent readout. The competitive PCR requires coamplification of a segment of the urease C sequence and an internal control standard in a competitive manner using a single set of primers. PCR products were quantified colorimetrically by an enzyme-linked immunosorbent assay and compared with known quantities of the internal control standard added to the PCR reaction. The highly sensitive, bioluminescent assay measures the amplified DNA directly using a flash-type luminescent tag and a specific probe. The Sydney strain of H. pylori was used for the mouse infection model. Quantification of H. pylori by either the bioluminescent assay or the competitive PCR was reliable, specific and sensitive compared to quantitative growth assays which often gave false results. The bioluminescent assay was much more sensitive and less labor/time intensive than the competitive PCR. The bioluminescent assay was able to quantitate as few as 100 bacteria, while the competitive assay could not detect less than 103 bacteria per mouse stomach. Quantification of H. pylori by bioluminescent assay was superior to the competitive assay and may be used for research applications, such as the development of vaccines, pathogenesis of gastric disease and monitoring of antibiotic treatment.

This paper reports the anomalous behavior of unloaded quality factor (Qu) of high Tcsuperconducting (HTSC) microstrip resonator in weak dc magnetic field (Bdc). The Qubehavior increases with the elevated applied Bdc, but beyond the certain Bdcvalue, decreases linearly with Bdc. We speculate that this behavior may be caused by edge effect. The behavior is modeled both by the coupled-grain model accounting for a distribution of the grain dimension and Coffey-Clem model.

Cardiovascular disease is rare in China, but there are few data on the prevalence of electrocardiographic (ECG) abnormalities in Chinese populations.

Conjugal transfer of the broad-host-range plasmid R1162 is initiated and terminated at the nic site within the 38-bp origin of transfer (oriT). Termination involves ligation of the transferred single strand by the plasmid-encoded MobA protein. Several different assays were used to identify the oriT DNA required for termination. For plasmids containing two oriTs, with transfer initiated at one and terminated at the other, the inverted repeat within oriT is important for termination. Deletion of the outer arm reduces the termination frequency; those terminations that do occur probably depend upon nicking at this oriT prior to transfer. The locations of second-site suppressor mutations indicate that base pairing between the arms of the inverted repeat is important for termination. In vitro, the inverted repeat is not required for specific cleavage of single-stranded DNA at nic, but competition experiments indicate that oriTs with the inverted repeat are preferentially cleaved. We propose that the function of the oriT inverted repeat is to trap the plasmid-encoded MobA protein at the end of a round of strand transfer, thus ensuring that the protein is available for the ligation step.

Given the lack of general mathematical model for the parameters of the globoidal indexing cam (GIC) mechanism, a method of modeling the contour for the GIC based on the unified mathematical expression is proposed by applying the envelope theory and the matrix transformation of the homogeneous coordinates. Taking the globoidal cams with cylindrical, conical, and hyperbolic meshing turret-rollers as the research object, a unified mathematical model of profile model for the GIC is derived. On this foundation, the general analytic expression of pressure angle and principal curvature is further obtained, which provides a theoretical basis for the precise design and manufacture of the GIC and provides a mathematical basis for the fatigue strength analysis of the GIC material.

Hydrogen decrepitation of Sm2Fe17followed by treatment in ammonia produces interstitial nitrides with nitrogen concentrations greater than three per formula unit. Measurements of the lattice parameters and magnetic properties are consistent with interstitial nitrogen occupation of the 9e and either the 3b or 18g sites. The effect of the extra nitrogen on the iron sublattice is to reduce the overall moment, particularly of the 18h sites. The magnetocrystalline anisotropy constants K1and K2indicate a significant decrease in the easy-axis character compared to Sm2Fe17N3material.