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1.
Pediatr Infect Dis J ; 40(11): e427-e433, 2021 11 01.
Article in English | MEDLINE | ID: mdl-34609109

ABSTRACT

BACKGROUND: We assessed nasopharyngeal pneumococcal carriage in Andean Kichwa children, the largest Amerindian indigenous population in the Ecuadorian Andes. All children in our study had been vaccinated with the 10-valent pneumococcal vaccine (PCV10). METHODS: Nasopharyngeal swabs from 63 families, 100 children <10 years old including 38 children under 5 years and 63 adult caregivers, from 5 different communities, were cultivated for Streptococcus pneumoniae and isolates were serotyped and antibiotic susceptibility testing was performed. RESULTS: Respectively, 67% of the 38 children under 5 years old, 49% of the 62 children between 6 and 10 years old and 16% of the 100 adults were colonized with S. pneumoniae. Of these, 30.9% carried a vaccine serotype, 5.4% a serotype shared by the PCV10/13-valent pneumococcal vaccine (PCV13) vaccine and 25.5% a PCV13 serotype or PCV13 vaccine-related serotype, with 19A (10.9%) and 6C (10.9%) as the most prominent. Drug susceptibility testing revealed that 46% of the S. pneumoniae strains were susceptible to 6 tested antibiotics. However, 20.3% of the strains were multidrug-resistant or extensively drug-resistant strains, including 82% of the vaccine (-related) serotype 19A and 6C strains. CONCLUSIONS: Kichwa children, vaccinated with PCV10, were highly colonized with pneumococci and should be considered a high-risk group for pneumococcal disease. Twenty-five percent of the colonizing S. pneumoniae strains were PCV13-only vaccine-targeted serotypes, and in addition to that, most were multidrug-resistant or extensively drug-resistant strains. The vaccine benefits for this population possibly will significantly increase with the introduction of PCV13.


Subject(s)
Carrier State/epidemiology , Carrier State/microbiology , Indigenous Peoples/statistics & numerical data , Nasopharynx/microbiology , Pneumococcal Infections/prevention & control , Pneumococcal Vaccines/administration & dosage , Streptococcus pneumoniae/isolation & purification , Adolescent , Adult , Anti-Bacterial Agents/pharmacology , Caregivers/statistics & numerical data , Child , Child, Preschool , Drug Resistance, Multiple, Bacterial , Ecuador/epidemiology , Female , Humans , Male , Microbial Sensitivity Tests , Middle Aged , Pneumococcal Infections/epidemiology , Serogroup , Streptococcus pneumoniae/classification , Streptococcus pneumoniae/drug effects , Vaccination , Young Adult
2.
Avian Pathol ; 50(4): 339-349, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34126819

ABSTRACT

Avian trichomonosis is a parasitic disease that affects wild birds. The objective of this work was to determine the importance of avian trichomonosis in Bonelli's eagles to improve conservation measures in this population. One hundred and eighty-eight birds were studied: 181 chicks, two juveniles, one subadult and four adults. The birds were externally examined and gross lesions at the oropharynx registered. Samples from the oropharyngeal cavity were obtained for Trichomonas spp. detection by culture and PCR, and positive samples were subjected to a multilocus sequence typing approach, including the ITS1/5.8S/ITS2 region (ITS), ribosomal RNA small subunit (18S) and Fe-hydrogenase gene (FeHyd). Global prevalence of T. gallinae infection was 37.8% in total, 45.5% in nestlings. Thirty-three percent of the birds developed lesions that ranged from mild (n = 41) to moderate (n = 14) or severe (n = 7). Multilocus sequence typing analysis showed five different MLS types, ITS-A/18S-VI/FeHyd-A1 and ITS-D/18S-II/Fe-C4 being the most frequent. An association between ITS-A/18S-VI/FeHyd-A1 and moderate or severe lesions was observed, but birds with type ITS-A/18S-VI/FeHyd-A2 also developed lesions. On the contrary, birds with MLS type ITS-D/18S-II/FeHyd-C4 displayed only a low proportion of mild lesions. Chicks raised in nests were at higher risk for T. gallinae infection and development of lesions than chicks raised in captivity. Discordances between samples cultured in TYM and samples subjected to PCR from oropharyngeal swabs were observed, swab-ITS-PCR being more sensitive.RESEARCH HIGHLIGHTS 45.5% of Bonelli's eagles in the nest carried T. gallinae and 39.4% showed lesions.PCR from oral swabs showed higher sensitivity than culture in TYM for detection of T. gallinae.MLS types ITS-A/18S-VI/Fe-A1 (and A2) are a risk factor for the development of lesions.


Subject(s)
Eagles , Trichomonas , Animals , Eagles/parasitology , Trichomonas/genetics , Trichomonas Infections/veterinary
3.
Appl Opt ; 51(21): 5161-7, 2012 Jul 20.
Article in English | MEDLINE | ID: mdl-22858958

ABSTRACT

In this work, the surface plasmon resonance (SPR) technique is used to determine the quality or adulteration of tequila beverages. Graphic analyses of the position and width of the SPR curve are related to the complex refractive index of the sample, showing differentiated regions where one can easily and unambiguously identify white, aged, or extra-aged tequilas, and even adulterated or low quality tequilas. The curves generated by aged and extra-aged tequilas, with respect to those obtained from white tequilas, are wider, while the resonant peak shifts towards larger angles. This behavior should be attributed to the aging process. The resonance curve is generated in 20 s, minimizing the variations of the SPR curve parameters due to temperature fluctuations.

4.
Opt Lett ; 27(8): 646-8, 2002 Apr 15.
Article in English | MEDLINE | ID: mdl-18007890

ABSTRACT

A new sensor based on optical surface waves in truncated one-dimensional photonic crystals is proposed for use in determining the optical properties of metallic or dielectric thin films and bulk media. Specifically, the method of optical characterization takes into account the changes that the surface waves of a layered structure undergo when either a thin film of arbitrary material is added at the surface or the optical properties of transmission medium change. For the surface-wave excitation the Kretschmann configuration used in attenuated total reflectance is employed.

5.
Circulation ; 104(6): 648-52, 2001 Aug 07.
Article in English | MEDLINE | ID: mdl-11489769

ABSTRACT

BACKGROUND: Adjunctive unfractionated heparin (UFH) during thrombolytic therapy for acute myocardial infarction (AMI) promotes the speed and magnitude of coronary artery recanalization and reduces reocclusion. Low-molecular-weight heparins offer practical and potential pharmacological advantages over UFH in multiple applications but have not been systematically studied as adjuncts to fibrinolysis in AMI. METHODS AND RESULTS: Four hundred patients undergoing reperfusion therapy with an accelerated recombinant tissue plasminogen activator regimen and aspirin for AMI were randomly assigned to receive adjunctive therapy for at least 3 days with either enoxaparin or UFH. The study was designed to show noninferiority of enoxaparin versus UFH with regard to infarct-related artery patency. Ninety minutes after starting therapy, patency rates (thrombolysis in myocardial infarction [TIMI] flow grade 2 or 3) were 80.1% and 75.1% in the enoxaparin and UFH groups, respectively. Reocclusion at 5 to 7 days from TIMI grade 2 or 3 to TIMI 0 or 1 flow and TIMI grade 3 to TIMI 0 or 1 flow, respectively, occurred in 5.9% and 3.1% of the enoxaparin group versus 9.8% and 9.1% in the UFH group. Adverse events occurred with similar frequency in both treatment groups. CONCLUSIONS: Enoxaparin was at least as effective as UFH as an adjunct to thrombolysis, with a trend toward higher recanalization rates and less reocclusion at 5 to 7 days.


Subject(s)
Anticoagulants/therapeutic use , Aspirin/therapeutic use , Enoxaparin/therapeutic use , Heparin/therapeutic use , Myocardial Infarction/drug therapy , Tissue Plasminogen Activator/therapeutic use , Anticoagulants/adverse effects , Coronary Angiography , Coronary Circulation/drug effects , Enoxaparin/adverse effects , Female , Heparin/adverse effects , Heparin, Low-Molecular-Weight/adverse effects , Heparin, Low-Molecular-Weight/therapeutic use , Humans , Intracranial Hemorrhages/chemically induced , Male , Middle Aged , Myocardial Infarction/mortality , Myocardial Infarction/physiopathology , Myocardial Reperfusion , Recombinant Proteins/therapeutic use , Survival Rate , Thrombolytic Therapy , Treatment Outcome
6.
Appl Opt ; 39(10): 1602-10, 2000 Apr 01.
Article in English | MEDLINE | ID: mdl-18345058

ABSTRACT

Experimental results from the emission of vapor sources are considered in designing correcting diaphragms to achieve a uniform thickness distribution during evaporation of thin films mounted on large-area substrate holders, in different geometric configurations.

7.
Appl Opt ; 35(28): 5595-9, 1996 Oct 01.
Article in English | MEDLINE | ID: mdl-21127562

ABSTRACT

The transmitted scattered energy of plane electromagnetic waves from a thin metallic film with shallow rough interfaces bounded by two semi-infinite media is calculated. Both interfaces are modeled as independent stationary random processes with a Gaussian roughness spectrum. Scattering of light is calculated for both TM (p) or TE (s) polarizations for normal and oblique angles of incidence. An integral equation is obtained for the transmitted field based on the Rayleigh method and their solution involves Fourier coefficients, depending on the roughness profiles. We present some results for the case of a single thin metallic film in the attenuated total reflection configuration for s and p polarization around the angle of the excitation of surface-plasma waves θ(sp). The transmitted scattered intensity shows a maximum at the resonant angle θ(sp) in the case of p polarization.

8.
Appl Opt ; 33(13): 2672-7, 1994 May 01.
Article in English | MEDLINE | ID: mdl-20885623

ABSTRACT

Admittance diagrams are used to analyze qualitatively and quantitatively the behavior of inhomogeneous thin films with an arbitrary refractive-index function. From this study it follows that one can treat the behavior of rugate filters by using the concept of effective refractive indices, which are associated with the phase integral in a simple way. These results are applied to the study of periodic systems, and, as expected, one can consider high and low effective refractive indices to determine the important parameters of these stop bands. With these ideas it is possible that one can deal with rugate filters more closely as homogeneous periodic systems by taking advantage of the existing theory.

9.
Appl Opt ; 32(28): 5677-82, 1993 Oct 01.
Article in English | MEDLINE | ID: mdl-20856386

ABSTRACT

The reflectivity R of a multilayer stack and its first and second derivatives with respect to the phase change are derived here by a recursive method. These equations improve the determination of stability conditions for coatings and widen the applications to treatments other than antireflection coatings, as reported by Mouchart [Appl. Opt. 16, 2486 (1977)]. Some calculations are performed on grazing incidence antireflection coatings, all-dielectric mirrors, and bandpass filters with non-quarter-wave layers.

10.
Appl Opt ; 30(19): 2778-81, 1991 Jul 01.
Article in English | MEDLINE | ID: mdl-20700274

ABSTRACT

The optical properties of a commercial parylene pellicle are obtained using a classical oscillator model with a single oscillator. Using a standard design antireflection stack and beam-splitter multilayer films coated on this pellicle, its performance is greatly improved, flattening the curve and increasing its useful spectral range.

11.
Appl Opt ; 30(22): 3176-80, 1991 Aug 01.
Article in English | MEDLINE | ID: mdl-20706371

ABSTRACT

In a glass-metal-dielectric system, it is normally impossible to determine simultaneously the complex dielectric constant, the thickness of the metal, and the corresponding parameters of a dielectric overlayer. We propose the use of the pseudo-Brewster or Abelés angle as an additional parameter to characterize simultaneously a dielectric thin-film overcoating and the metal surface parameters. We use a Kretschmann attenuated-total-reflection configuration. An admittance diagram is used to illustrate graphically the role of an absentee layer at this angle. A study of the limitations of the method is also presented.

12.
Appl Opt ; 27(12): 2549-53, 1988 Jun 15.
Article in English | MEDLINE | ID: mdl-20531790

ABSTRACT

The values of the optical constants of magnesium fluoride (MgF(2)) and zinc sulfide (ZnS) thin films are obtained using a classical oscillator model and the experimental values of their spectral transmittance. Auger electron spectroscopy was performed on the samples to determine the chemical composition of the films. These materials are important in the design of filters, mirrors, and antireflection coatings for optical instrumentation. Unfortunately their properties strongly depend on evaporation conditions. The procedure described here allows direct measurement of the dispersive refractive index of the film after deposition.

13.
Appl Opt ; 27(20): 4260-4, 1988 Oct 15.
Article in English | MEDLINE | ID: mdl-20539554

ABSTRACT

We propose a method for determination of the complex refractive index of absorbing materials either in bulk or film geometry by measuring its reflectivity when coated with a well-characterized transparent dielectric at two specific optical thicknesses: n(1)d(1) = lambda(0)/4 and n(1)d(1) = lambda(0)/2. The complex refractive index of the sample ñ = (n,k) is calculated for the monitoring wavelength lambda(0). The selected optical thicknesses of the coating allow the calculation of its geometrical thickness, therefore the variation of ñ with wavelength in the region where the reflectivity is measured can be determined.

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