RESUMO
Orthopoxvirus infections appear to be rare in South American Camelids, because only a few cases have been reported in the literature. Based on a generalized infection with cowpox virus in an alpaca, the clinical symptoms, laboratory diagnostic findings and the pathological changes are described. The case history showed a long treatment because of chronic skin lesions. The main clinical symptom was miliary papules over the entire skin. Furthermore, a bilateral mucopurulent conjunctivitis occurred as well as excessive salivation due to a severe erosive-ulcerative stomatitis. Although the animal received intensive treatment, it died 8 days after admission to the clinic. During necropsy, an erosive-ulcerative laryngitis as well as a necrotising pneumonia and lymphadenitis were observed. Histopathological examination of representative organ samples led to the diagnosis of a suspected orthopoxvirus infection. Electron microscopy and quantitative polymerase chain reaction (qPCR) of tissue samples confirmed this diagnosis. The virus could be isolated in tissue culture and a PCR with subsequent nucleotide sequencing identified cowpox virus as the causative agent for this generalised infection.
Assuntos
Camelídeos Americanos/virologia , Vírus da Varíola Bovina/isolamento & purificação , Varíola Bovina/veterinária , Animais , Varíola Bovina/virologiaRESUMO
We report on the generation of 250mW of coherent 460-nm light by single-pass frequency doubling of the mode-locked picosecond pulses emitted by an InGaAs diode master oscillator power amplifier in periodically poled KTP.
RESUMO
Blue 465-nm radiation is generated by frequency doubling of the output of an InGaAs diode-laser oscillator-amplifier system in critically phase-matched LiB(3)O(5) (LBO). The diode-laser system emitted 4 W of single-frequency 930-nm radiation in a near-diffraction-limited beam (M(2)<1.2) . The laser power is enhanced to values of up to 150 W in a resonant external ring cavity. The LBO crystal is placed at a resonator internal focus. The frequency doubling in the LBO crystal generates blue radiation at 465 nm with a power of 1 W. The spectral width of the blue radiation is less than 3 MHz, and the value of the M(2) beam parameter is less than 1.2.
RESUMO
We report on the fabrication and characterization of quasi-phase-matched potassium niobate crystals for second-harmonic generation. Periodic 30-mum -pitch antiparallel ferroelectric domains are fabricated by means of poling in an electrical field. Both birefrigence and periodic phase shift of the generated second harmonic contribute to phase matching when the d(31) nonlinear optical tensor element is used. 3.8 mW of second-harmonic radiation at 463 nm is generated by frequency doubling of the output of master-oscillator power-amplifier diode laser in a 5-mm-long crystal. The measured effective nonlinear coefficient is 3.7pm/V. The measured spectral acceptance bandwidth of 0.25 nm corresponds to the theoretical value.
RESUMO
We report continuous-wave single-pass second-harmonic generation (SHG) in 4-mum -period 0.5-mm-thick backswitch-poled lithium niobate. Pump sources at 920-930 nm include both Ti:sapphire and diode-oscillator-amplifier lasers. SHG of a Ti:sapphire laser at 6.1%/W efficiency, producing 61 mW of power at 460 nm, is demonstrated in 50-mm-long periodically poled lithium niobate samples with a nonlinear coefficient d(eff) approximately 9pm/V, and 60 mW at 465 nm and 2.8%/W efficiency is obtained by SHG of a laser-diode source.
RESUMO
The presence of p24 core antigen in the serum of individuals with human acquired immunodeficiency syndrome has been used as one of the important prognostic markers of HIV-1 infection and also as an end point in evaluating antiviral drugs and vaccines. Unfortunately the majority of p24 antigen present in serum exists as an antigen-antibody complex and is not detected with the commercial kits currently available to measure p24 antigen. In this study, we report a simple procedure utilizing treatment of serum samples with glycine buffer (pH 1.85) to dissociate antigen-antibody complexes prior to assaying for p24 antigen. A 300% increase in the number of p24-reactive samples and a 3- to 12-fold increase in the quantity of antigen detected were observed when samples were pretreated with 1.5 M glycine buffer (pH 1.85) for 1 hr. Glycine treatment of samples did not result in non-specific positive tests and samples previously shown to be reactive remained positive. In reconstruction experiments the release of antigen was found to be inversely proportional to the amount of p24 antibody present in the serum. The percentage of HIV-1-infected patients positive for p24 antigen was clearly a function of CD4 count. Forty-nine percent of patients with more than 500 CD4 cells and 100% of patients with less than 200 CD4 were p24 positive.(ABSTRACT TRUNCATED AT 250 WORDS)