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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 311: 123977, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38310743

RESUMO

A rapid, simple, sensitive, and selective point-of-care diagnosis tool kit is vital for detecting the coronavirus disease (COVID-19) based on the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strain. Currently, the reverse transcriptase-polymerase chain reaction (RT-PCR) is the best technique to detect the disease. Although a good sensitivity has been observed in RT-PCR, the isolation and screening process for high sample volume is limited due to the time-consuming and laborious work. This study introduced a nucleic acid-based surface-enhanced Raman scattering (SERS) sensor to detect the nucleocapsid gene (N-gene) of SARS-CoV-2. The Raman scattering signal was amplified using gold nanoparticles (AuNPs) possessing a rod-like morphology to improve the SERS effect, which was approximately 12-15 nm in diameter and 40-50 nm in length. These nanoparticles were functionalised with the single-stranded deoxyribonucleic acid (ssDNA) complemented with the N-gene. Furthermore, the study demonstrates method selectivity by strategically testing the same virus genome at different locations. This focused approach showcases the method's capability to discern specific genetic variations, ensuring accuracy in viral detection. A multivariate statistical analysis technique was then applied to analyse the raw SERS spectra data using the principal component analysis (PCA). An acceptable variance amount was demonstrated by the overall variance (82.4 %) for PC1 and PC2, which exceeded the desired value of 80 %. These results successfully revealed the hidden information in the raw SERS spectra data. The outcome suggested a more significant thymine base detection than other nitrogenous bases at wavenumbers 613, 779, 1219, 1345, and 1382 cm-1. Adenine was also less observed at 734 cm-1, and ssDNA-RNA hybridisations were presented in the ketone with amino base SERS bands in 1746, 1815, 1871, and 1971 cm-1 of the fingerprint. Overall, the N-gene could be detected as low as 0.1 nM within 10 mins of incubation time. This approach could be developed as an alternative point-of-care diagnosis tool kit to detect and monitor the COVID-19 disease.


Assuntos
COVID-19 , Nanopartículas Metálicas , Nanotubos , Ácidos Nucleicos , Humanos , Análise Espectral Raman/métodos , Ouro , Análise de Componente Principal , SARS-CoV-2/genética , COVID-19/diagnóstico , Nucleocapsídeo
2.
Ticks Tick Borne Dis ; 13(3): 101942, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35339917

RESUMO

Heartwater, Ehrlichia ruminantium infection in cattle, sheep, goats, and some wild ruminants, is an economically important disease in Africa characterized by high mortality rates in susceptible populations. In South Africa, the current commercial heartwater vaccine is an infection and treatment type of immunization using virulent live E. ruminantium organisms generated from blood of infected sheep with subsequent treatment of the animals with antibiotics at specific times during the course of infection. This vaccine has several inherent problems preventing its wide use as the vaccine must be administered intravenously and it does not protect against all the South African field isolates. A vaccine based on inactivation of Zimbabwean E. ruminantium Mbizi strain organisms produced in endothelial cell cultures can be a sustainable option because it will not require antibiotic treatment and will be safe as there is no potential for reversion to virulence. Previous data generated in laboratory trials and under natural field setting provides support for this vaccine approach. Four inactivated vaccine formulations using the E. ruminantium Mbizi strain were tested for their efficacy in Merino sheep compared to an unvaccinated control group (11 sheep per group). Two vaccines were prepared by beta-propiolactone (BPL) inactivation, and two were inactivated with binary ethylenimine (BEI) while purification was done with both percoll and polyethylene glycol (PEG). The four vaccine preparations were formulated with Montanide ISA 50V2 adjuvant and administered twice subcutaneously (2 ml per dose) at an interval of 4 weeks. All groups were challenged with a virulent homologous cell-cultured E. ruminantium inoculated via the intra-venous route on day 56. The primary variable of efficacy was measured by the percentage survival rate or mortality between the Controls and Vaccine Groups. Three vaccine formulations (BEI/Percoll (Group 3), BEI/PEG (Group 4), BPL/Percoll, (Group 1) had a significantly higher percent of animal surviving challenge compared to the unvaccinated control (p-values 0.001, 0.035, 0.030, respectively). The highest number of survivors was obtained in Group 3 BEI/Percoll; 10/11 (91%). Groups 4 (BEI/PEG) and Group 1 (BPL/Percoll) produced similar percentage of survivals of 64%. In contrast, the lowest survival rate of 50% was observed in Group 2 (BPL/PEG) which was numerically different but not significantly different from the unvaccinated control which had an 18% survival rate (2/11). The inactivated vaccine using BEI or BPL as inactivating agents blended with ISA 50 adjuvant induced protective immunity against challenge. The BEI/Percoll (Group 3) vaccination regimen was most efficacious against a lethal heartwater challenge as it significantly protected sheep against mortality which is the most important aspect of heartwater infections. Future work should be directed towards improvement of this vaccine formulation especially from the down-stream processing point of view as the percoll method is not scalable for commercialization purposes.


Assuntos
Ehrlichia ruminantium , Hidropericárdio , Animais , Vacinas Bacterianas , Bovinos , Hidropericárdio/prevenção & controle , Óleo Mineral , Ovinos , África do Sul
3.
Arch. Soc. Esp. Oftalmol ; 96(12): 640-648, dic. 2021. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-218360

RESUMO

Objetivo Evaluar la eficacia y seguridad de la terapia láser transescleral MicroPulse® (TLT) en el tratamiento de pacientes con glaucoma. Métodos Se llevó a cabo una serie de casos prospectiva, intervencionista y no comparativa en el Servicio de Oftalmología del Hospital Universitario Ain Shams en 61 ojos de 46 pacientes con diversos tipos de glaucoma y de gravedad, de leves a graves. Además de la agudeza visual mejor corregida, se registraron la presión intraocular (PIO) y el número de medicamentos para el glaucoma antes y después del tratamiento, junto con la necesidad postoperatoria de inhibidores sistémicos de la anhidrasa carbónica, las tasas de éxito, el número de sesiones de tratamiento y las complicaciones postoperatorias. El éxito se definió como una PIO de 6-18mmHg o una disminución de al menos el 30% de la PIO preoperatoria en ausencia de complicaciones que amenazaran la visión durante el periodo de seguimiento de 6 meses. Resultados Se realizó la TLT MicroPulse® en 61 ojos glaucomatosos. Se repitió la sesión de TLT MicroPulse® en 11 de los 61 ojos (18%) que no alcanzaron una PIO entre 6 y 18mmHg, o una disminución de al menos el 30% con respecto al valor inicial a los 6 meses. A los 6 meses de seguimiento tras una única sesión de TLT MicroPulse® la reducción media de la PIO fue del 35,9%±14,2%, y 6 meses después de la segunda sesión fue del 36,2%±17,5% (p<0,001). La tasa de éxito tras la primera sesión fue del 73,8%, que aumentó al 78,7% tras la segunda sesión. La reacción celular media de la cámara anterior fue de+1,9±0,8 al primer día,+1,0±0,7 a la primera semana y+0,2±0,4 al primer mes del postoperatorio. No se detectaron células en ninguno de los casos a los 3 y 6 meses de seguimiento (p<0,001). El número medio de colirios antiglaucomatosos antes del TLT MicroPulse® fue de 2,6±1,0 (AU)


Objective To evaluate the efficacy and safety of MicroPulse® transscleral laser therapy (TLT) in the management of glaucoma patients. Methods A prospective, interventional, non-comparative case series was conducted in the department of ophthalmology, Ain Shams University Hospital on 61 eyes of 46 patients with various glaucoma types and of severity, ranging from mild to severe. In addition to best-corrected visual acuity (BCVA), intraocular pressure (IOP) and the number of glaucoma medications were recorded before and after treatment, along with the postoperative need for systemic carbonic anhydrase inhibitors (CAI), success rates, number of treatment sessions and postoperative complications. Success was defined as an IOP of 6-18mmHg or at least a 30% decrease from preoperative IOP in the absence of any vision-threatening complications during the 6-month follow-up period. Results MicroPulse TLT was performed on 61 glaucomatous eyes. Eleven of the 61 eyes (18%) that did not achieve IOP between 6-18mmHg, or at least a 30% decrease from baseline at 6 months, had a repeat MicroPulse TLT session. At 6 months follow-up post a single MicroPulse TLT session, the mean IOP reduction was 35.9±14.2%; and 6 months after the second session, it was 36.2±17.5% (P<.001). The success rate after the first session was 73.8% which increased to 78.7% after the second session. The mean anterior chamber (AC) cell reaction was+1.9±.8 at 1 day,+1.0±.7 at 1 week, and+.2±.4 at 1 month postoperatively. No cells were detected in any of the cases at 3 and 6 months follow-up (P<.001). The average number of anti-glaucoma eye drops before MicroPulse TLT was 2.6±1.0. Postintervention, the average number of anti-glaucoma eye drops was 1.7±1.2, and sustained at 6 months follow-up after the last treatment session (P<.001). There were no significant complications were noted. One eye developed transient hypotony for 3 months after MicroPulse TLT (AU)


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Glaucoma/cirurgia , Estudos Prospectivos , Resultado do Tratamento , Acuidade Visual , Corpo Ciliar , Pressão Intraocular , Fotocoagulação a Laser , Terapia a Laser
4.
Arch Soc Esp Oftalmol (Engl Ed) ; 96(12): 640-648, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34844684

RESUMO

PURPOSE: To evaluate the efficacy and safety of MicroPulse® transscleral laser therapy (TLT) in the management of glaucoma patients. METHODS: A prospective, interventional, non-comparative case series was conducted in the department of ophthalmology, Ain Shams University Hospital on 61 eyes of 46 patients with various glaucoma types and of severity, ranging from mild to severe. In addition to best-corrected visual acuity (BCVA), intraocular pressure (IOP) and the number of glaucoma medications were recorded before and after treatment, along with the postoperative need for systemic carbonic anhydrase inhibitors (CAI), success rates, number of treatment sessions and postoperative complications. Success was defined as an IOP of 6-18 mmHg or at least a 30% decrease from preoperative IOP in the absence of any vision-threatening complications during the 6-month follow-up period. RESULTS: MicroPulse TLT was performed on 61 glaucomatous eyes. Eleven of the 61 eyes (18%) that did not achieve IOP between 6-18 mmHg, or at least a 30% decrease from baseline at 6 months, had a repeat MicroPulse TLT session. At 6 months follow-up post a single MicroPulse TLT session, the mean IOP reduction was 35.9 ± 14.2%; and 6 months after the second session, it was 36.2 ± 17.5% (p < 0.001). The success rate after the first session was 73.8% which increased to 78.7% after the second session. The mean anterior chamber (AC) cell reaction was +1.9 ± 0.8 at 1 day, +1.0 ± 0.7 at 1 week, and +0.2 ± 0.4 at 1 month postoperatively. No cells were detected in any of the cases at 3 and 6 months follow-up (p < 0.001). The average number of anti-glaucoma eye drops before MicroPulse TLT was 2.6 ± 1.0. Postintervention, the average number of anti-glaucoma eye drops was 1.7 ± 1.2, and sustained at 6 months follow-up after the last treatment session (p < 0.001). There were no significant complications were noted. One eye developed transient hypotony for 3 months after MicroPulse TLT. CONCLUSIONS: MicroPulse TLT is safe and effective in lowering IOP in a variety of glaucoma types and severity.


Assuntos
Glaucoma , Terapia a Laser , Corpo Ciliar , Glaucoma/cirurgia , Humanos , Pressão Intraocular , Fotocoagulação a Laser , Estudos Prospectivos , Resultado do Tratamento , Acuidade Visual
5.
Climacteric ; 23(4): 397-403, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32299254

RESUMO

Objective: This study aimed to compare efficacy and safety of lidocaine versus tramadol versus placebo in reducing the pain of diagnostic outpatient hysteroscopy (OH) in postmenopausal women.Materials and methods: This randomized double-blinded study included 156 menopausal women who received intrauterine lidocaine infusion or oral tramadol (50 mg) or placebo before diagnostic OH (52 women/group). Primary outcome was pain severity during the procedure using a 10-cm visual analog scale. Secondary outcomes were pain scores 10 and 30 min post procedure, satisfaction level, and ease of cervical entry.Results: Lidocaine had lower pain scores compared to placebo during and 10 min after the procedure (p < 0.001). Tramadol had lower pain scores than placebo during the procedure (p = 0.04), 10 min after the procedure (p = 0.03), and 30 min after the procedure (p = 0.04). Both lidocaine and tramadol resulted in an easier procedure than placebo (p < 0.001 and p = 0.04, respectively). Lidocaine had an easier cervical entry compared to tramadol (p = 0.004). Satisfaction scores in the lidocaine and tramadol groups were significantly higher than in the placebo group (p < 0.001).Conclusions: Lidocaine and tramadol were effective in reducing postmenopausal women-reported pain during and after diagnostic OH. However, lidocaine was better than tramadol in facilitating hysteroscope passage through the cervical canal and the reduction in pain levels with lidocaine was clinically relevant.Trial registration number: NCT03701984.


Assuntos
Analgésicos/uso terapêutico , Lidocaína/uso terapêutico , Dor Pós-Operatória/tratamento farmacológico , Dor Processual/tratamento farmacológico , Tramadol/uso terapêutico , Procedimentos Cirúrgicos Ambulatórios/efeitos adversos , Procedimentos Cirúrgicos Ambulatórios/métodos , Método Duplo-Cego , Feminino , Humanos , Histeroscopia/efeitos adversos , Histeroscopia/métodos , Pessoa de Meia-Idade , Manejo da Dor/métodos , Medição da Dor , Dor Pós-Operatória/etiologia , Dor Processual/etiologia , Pós-Menopausa , Estudos Prospectivos , Resultado do Tratamento
6.
Egypt J Occup Med ; 43(3): 331-343, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32194314

RESUMO

BACKGROUND: Adolescent females living in agricultural areas where crops are routinely sprayed by pesticides are expected to be environmentally exposed to pesticides' health hazards partially as those occupationally exposed. OBJECTIVE: to assess menstrual and neurobehavioral disorders among adolescent females environmentally exposed to pesticides. METHODS: This was a cross-sectional study conducted on 100 pesticide exposed adolescent females who had one or more of family members are pesticides' seasonal applicators and 50 non- exposed adolescent females matched for age and education, served as controls at Menoufia governorate, Egypt during the period of pesticide application season of cotton crop from the first days of May to the end of September 2017. A self-administered and a series of neurobehavioral tests were administered and serum Acetylcholinesterase (AChE) activity was assessed. RESULTS: A significant lower AChE activity levels were found in the exposed group than controls (Mean±SD=238.49± 23.83 vs 303.35±78.54 IU/L; respectively). There were significant higher mean scores of trail making test (parts 1 and 2) and significant lower mean scores of (similarities test, Benton visual retention test, block design test, Santa Ana dexterity test (dominant and non-dominant hands) and Beery visuo-motor imitation test in the exposed group than the controls (P<0.05). Also, the exposed group reported more prevalent irregular menstrual cycle (26.8%) and intermenstrual bleeding (28.2%) compared to the control participants (8.1% and 8.1%; respectively). CONCLUSION: Adolescent females living in agricultural areas and from families whose one or more members are pesticides' applicators have significantly lower neurobehavioral performance, report more prevalent menstrual irregularities and have lower levels of serum AChE compared to a control group. The neurobehavioral deficits demonstrated a dose-response relationship AChE levels in the exposed participants. This necessitates the need for implementation of health education programs to prevent or reduce health effects associated with pesticide exposure to adolescent females.

7.
Phys Chem Chem Phys ; 20(33): 21447-21456, 2018 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-30087964

RESUMO

The reversibility of current Li-O2 batteries suffers from high charging overpotentials. To address this problem, the use of redox mediators has been proposed, which are supposed to improve the sluggish reaction kinetics of the oxygen evolution reaction via a solution mediated oxidation of lithium peroxide. In this study, we present a new thin layer cell for battery related differential electrochemical mass spectrometry (DEMS) experiments, which exhibits a high electrode surface area to electrolyte volume ratio which is closer to the situation in batteries other approaches/cells with their usually large electrolyte excess. The confined volume also allows a better distinction between the mediating activity of a redox system and a near continuous electrochemical reaction of this species. One further benefit of the new thin layer cell is that experiments can easily be performed under different O2-partial pressures. This new set-up allows the highly sensitive detection of volatile species formed during the OER. Therefore, small changes in the number of electrons transferred per oxygen molecule are observable. These changes help to identify side reactions and possible decomposition of the reaction products. During our experiments, we investigated the impact of TTF, TMPD, Fc and TEMPO on the oxidation of Li2O2. Within our experiments, we are able to precisely determine the potential at which the catalytic activity of the redox mediation starts. A comparison between the potential at which we observe the activity of the redox mediator to the half wave potential of the redox system could be explained with an outer sphere electron transfer for the oxidation of Li2O2 by a redox mediator. This observation is confirmed by a theoretical treatment of the redox mediation mechanism. Moreover, insights into the number of transferred electrons per oxygen molecule during the activity of the different redox mediators reveal the presence of side reactions. This finding is also underlined by an unexpected shift of the CO2 evolution onset for the redox mediator containing electrolytes. Our experiments also reveal that a Li-O2 cell, which contains a redox mediator, undergoes less fluctuation in its reversibility compared to a cell without a redox mediator.

8.
Opt Express ; 26(10): 12790-12800, 2018 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-29801314

RESUMO

Mode-locked fiber laser incorporating a saturable absorber is an attractive configuration due to its stability and simple structure. In this work, we demonstrate a dual-wavelength passively mode-locked erbium-doped fiber laser employing a graphene/polymethyl-methacrylate saturable absorber. A laser resonator is developed based on dual cavity architecture with unidirectional signal oscillation, which is connected by a fiber branch sharing a common gain medium and saturable absorber. Dual wavelength mode-locked fiber lasers are observed at approximately 1530 and 1560 nm with 22.6 mW pump power threshold. Soliton pulse circulates in the laser cavity with pulse duration of 900 and 940 fs at shorter and longer wavelengths, respectively. This work presents a viable option in developing a low threshold mode-locked laser source with closely spaced dual wavelength femtosecond pulses in the C-band wavelength region.

9.
Ticks Tick Borne Dis ; 8(4): 671-674, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28499721

RESUMO

A high-passage Babesia bovis vaccine containing only one genotype population was, although protective, inferior compared to the immunity afforded by a lower passage of the same strain containing two populations. The 24 times serially passaged South African B. bovis S vaccine strain contain only a single parasite population (Bv80 allele A 558bp). Forty-four field isolates sampled were all found different with regard to the number and composition of the parasite populations present in each isolate. The extensive genotypic diversity in South Africa and the limited genotypic diversity observed in the S24 vaccine, raised the question on its ability to protect against such diverse populations. The 6 isolates selected for challenge in the current study originated from geographically distinct populations that also possessed thirteen unique genotypes based on the Bv80 gene and included strains that resulted in clinical disease. The strain coverage was therefore much greater than in previous studies on the protective ability of the S24 vaccine. Challenge of vaccinated cattle indicated that the vaccine gave adequate protection against 5/6 isolates. Protection against the remaining isolate proved inadequate. However, field observations in the region where this isolate originated from, showed only minor mortalities in vaccinated animals compared to losses experienced in unvaccinated herds. This study demonstrated the ability of the South African B. bovis S24 vaccine to protect cattle against challenge from local field isolates containing single or multiple parasite populations.


Assuntos
Babesia bovis/imunologia , Babesiose/prevenção & controle , Doenças dos Bovinos/prevenção & controle , Vacinas Protozoárias/imunologia , Animais , Bovinos , África do Sul
10.
Phys Chem Chem Phys ; 17(43): 29394, 2015 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-26484887

RESUMO

Correction for 'Oxygen reduction and oxygen evolution in DMSO based electrolytes: the role of the electrocatalyst' by C. J. Bondue et al., Phys. Chem. Chem. Phys., 2015, 17, 25593-25606.

11.
Phys Chem Chem Phys ; 17(38): 25593-606, 2015 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-26371703

RESUMO

In the present paper the role of the electrode material in oxygen reduction in DMSO based electrolytes is elucidated using DEMS. We have found, employing platinum, gold, ruthenium rhodium, selenium decorated rhodium and boron doped diamond (BDD) as electrode materials, that the actual mechanism of oxygen reduction largely depends on the electrode material. At platinum, rhodium and selenium decorated rhodium the final reduction product, peroxide, is formed electrochemically. At gold and at low overpotentials oxygen is reduced to superoxide and peroxide is only formed by disproportionation of the latter. No oxygen reduction takes place at the diamond surface of the BDD-electrode, hence, showing unambiguously that oxygen reduction is an inner sphere reaction. Also, the rate of oxygen evolution varies with the electrode material, although the onset potential of oxygen evolution is not influenced. The amount of peroxide formed is limited to 1-2 monolayers. Contrary to intuition oxygen reduction and oxygen evolution from peroxide, therefore, are heterogeneous, electrocatalytic reactions. The finding of such an electrocatalytic effect is of great importance for the development and optimization of lithium-air batteries. Aside from the electrode material there are also effects of water as well as of the cation used in the electrolyte. This suggests an influence of the double layer at the interface between the electrode and the electrolyte on oxygen reduction in addition to the well-known higher stability of Na2O2 and K2O2. Electrospray ionization (ESI) results show that any effect of water in the Li(+) containing electrolyte is not due to an altered solvation of the cation.

12.
Ticks Tick Borne Dis ; 6(2): 158-63, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25544307

RESUMO

The South African Babesia bovis live blood vaccine, originating from a field isolate attenuated by 23 serial syringe passages in splenectomized calves, has lost the ability to infect the natural vector Rhipicephalus (Boophilus) microplus. In this study, infection with mixed parasites from the vaccine strain and a field isolate, resulted in transmission of both genotype populations. Comparing the field isolate and transmitted combination indicated no significant difference in their virulence, while challenge of vaccinated cattle with these isolates showed the ability of the vaccine to protect against both. Limiting dilution of the transmitted combination, followed by infection of splenectomized cattle (n=34) yielded no single infections for the vaccine strain genotype, seven clonal lines of the field isolate and one mixture of vaccine strain and field isolate. Only one of two field isolate clonal lines selected for vector transmission study was transmitted. Showing that B. bovis isolates can contain both tick transmissible and non-transmissible subpopulations. The findings of this study also indicate the probability of vaccine co-infection transmission occurring in the field, which may result in new genotype populations of B. bovis. However, the impact of this recombination with field isolates is considered negligible since a genotypically diverse population of B. bovis is already present in South Africa.


Assuntos
Vetores Aracnídeos/parasitologia , Babesia bovis/fisiologia , Babesiose/transmissão , Doenças dos Bovinos/transmissão , Rhipicephalus/parasitologia , Animais , Babesia bovis/patogenicidade , Babesiose/parasitologia , Bovinos , Doenças dos Bovinos/parasitologia , Coinfecção/veterinária , Feminino , Genótipo , África do Sul , Vacinas , Virulência
13.
Vet Parasitol ; 199(3-4): 144-52, 2014 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-24231390

RESUMO

Genotypic diversity in Babesia bovis (cause of Asiatic redwater in cattle) vaccine strains and field isolates from South Africa were investigated using the Bv80 gene as well as microsatellites. The S11 vaccine strain possessed both A and B alleles of the Bv80 gene, as well as genotypic diversity within each allele type as defined by repeat variation resulting in different amplicon sizes. Rapid serial passage of vaccine strain from passage S10 to S24 resulted in loss of genotypic diversity that yielded a single allele A genotype with an amplicon size of 558 bp. This suggested that clonal selection occurred during rapid passaging. Extensive genotypic diversity exists in 44 field isolates characterized with both Bv80 A and B alleles, but can be readily distinguished from the S24 vaccine strain using either the Bv80 allele specific PCR assays or using multi-locus micro-satellite typing. This indicated that no recent documented clinical cases of Asiatic redwater were caused by the reversion to virulence of the current vaccine strain.


Assuntos
Babesia bovis/genética , Babesiose/veterinária , Doenças dos Bovinos/parasitologia , Variação Genética , Alelos , Sequência de Aminoácidos , Animais , Babesia bovis/classificação , Babesia bovis/isolamento & purificação , Babesiose/parasitologia , Bovinos , Genótipo , Repetições de Microssatélites/genética , Filogenia , Vacinas Protozoárias/genética , Alinhamento de Sequência , Inoculações Seriadas , África do Sul
14.
Vet Parasitol ; 170(1-2): 30-6, 2010 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-20207488

RESUMO

Serological responses of field cattle (260) on a farm in KwaZulu-Natal, South Africa were determined before and after vaccination with the commercial Babesia bovis live-blood vaccine, using the indirect fluorescent antibody test (IFAT). All the cattle tested negative for B. bovis antibodies before vaccination while 83% of them had significant antibody titres (>or=1/80) to Babesia bigemina, indicating a high degree of natural exposure to the latter parasite. By Day 60 post-vaccination only 53% of the cattle had seroconverted to B. bovis. This raised the question as to why only half of the vaccinated cattle had seroconverted. The possibility of previous exposure to B. bigemina infection interfering with the development of detectable antibodies to B. bovis was therefore investigated under controlled conditions. It was found that simultaneous vaccination with B. bigemina and B. bovis (n=6), and B. bigemina vaccination followed by B. bovis vaccination (n=12), had no effect on the animals' immune responses to B. bovis vaccination. All of these cattle developed a significant antibody response. However, only 58% of cattle (n=12) which had previously been inoculated with the B. bigemina field isolate, obtained from the trial farm, seroconverted (>or=1/80) after B. bovis vaccination, yet parasites for B. bovis could be demonstrated microscopically in all of the animals in this group. These findings confirmed the serology results from the field trial. When challenged with a B. bovis field isolate, cattle in this group did not show clinical reactions compared with an unvaccinated control group. The judicious use of IFAT to establish vaccination success obtained with the current South African B. bovis vaccine is indicated.


Assuntos
Babesia bovis/imunologia , Babesiose/veterinária , Doenças dos Bovinos/parasitologia , Imunização/veterinária , Vacinas Protozoárias/imunologia , Animais , Anticorpos Antiprotozoários/sangue , Babesiose/imunologia , Babesiose/parasitologia , Babesiose/prevenção & controle , Temperatura Corporal/fisiologia , Bovinos , Doenças dos Bovinos/imunologia , Doenças dos Bovinos/prevenção & controle , Hematócrito/veterinária , Imunização/normas , Distribuição Aleatória
15.
Acta Anaesthesiol Scand ; 54(5): 549-56, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19919581

RESUMO

BACKGROUND: This double-blinded study aimed at evaluating and comparing the effects of magnesium and lidocaine on pain, analgesic requirements, bowel function, and quality of sleep in patients undergoing a laparoscopic cholecystectomy (LC). METHODS: Patients were randomized into three groups (n=40 each). Group M received magnesium sulfate 50 mg/kg intravenously (i.v.), followed by 25 mg/kg/h i.v., group L received lidocaine 2 mg/kg i.v., followed by 2 mg/kg/h i.v., and group P received saline i.v. Bolus doses were given over 15 min before induction of anesthesia, followed by an i.v. infusion through the end of surgery. Intraoperative fentanyl consumption and averaged end-tidal sevoflurane concentration were recorded. Abdominal and shoulder pain were evaluated up to 24 h using a visual analog scale (VAS). Morphine consumption was recorded at 2 and 24 h, together with quality of sleep and time of first flatus. RESULTS: Lidocaine or magnesium reduced anesthetic requirements (P<0.01), pain scores (P<0.05), and morphine consumption (P<0.001) relative to the control group. Lidocaine resulted in lower morphine consumption at 2 h [4.9 + or - 2.3 vs. 6.8 + or - 2.8 (P<0.05)] and lower abdominal VAS scores compared with magnesium (1.8 + or - 0.8 vs. 3.2 + or - 0.9, 2.2 + or - 1 vs. 3.6 + or - 1.6, and 2.1 + or - 1.4 vs. 3.3 + or - 1.9) at 2, 6, and 12 h, respectively (P<0.05). Lidocaine was associated with earlier return of bowel function and magnesium was associated with better sleep quality (P<0.05). CONCLUSION: I.v. lidocaine and magnesium improved post-operative analgesia and reduced intraoperative and post-operative opioid requirements in patients undergoing LC. The improvement of quality of recovery might facilitate rapid hospital discharge.


Assuntos
Anestésicos/administração & dosagem , Colecistectomia Laparoscópica/métodos , Lidocaína/administração & dosagem , Sulfato de Magnésio/administração & dosagem , Dor Pós-Operatória/prevenção & controle , Adulto , Analgésicos Opioides/administração & dosagem , Anestésicos Inalatórios , Protocolos Clínicos , Método Duplo-Cego , Feminino , Fentanila/administração & dosagem , Humanos , Masculino , Éteres Metílicos , Medição da Dor , Estudos Prospectivos , Sevoflurano , Fatores de Tempo , Resultado do Tratamento
16.
J S Afr Vet Assoc ; 79(1): 31-5, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18678189

RESUMO

Theileria parva causes widespread morbidity and mortality in cattle in endemic regions. An outbreak of theileriosis occurred on a farm near Ladysmith in KwaZulu-Natal, South Africa, which is not a declared Corridor disease-infected area. A survey of Red Brangus cattle from all age groups and areas of the farm was performed. Transmission of the parasite from infected animals on the farm to susceptible animals by tick transmission and tick-stabilate injection, was attempted. The survey indicated high numbers of animals with antibody titres to T. parva but only 6 infected animals, based on real-time PCR and RLB analysis. The transmission experiments failed to transmit the parasite. The study shows the difficulty in elucidating a source of infection and determining the dynamics of new infections in a herd where multiple possible sources are present and treatment with tetracyclines has taken place.


Assuntos
Anticorpos Antiprotozoários/sangue , Vetores Aracnídeos/parasitologia , Theileria parva/imunologia , Theileriose/epidemiologia , Carrapatos/parasitologia , Animais , Bovinos , Surtos de Doenças/veterinária , Feminino , Masculino , Reação em Cadeia da Polimerase/métodos , Reação em Cadeia da Polimerase/veterinária , Prevalência , África do Sul/epidemiologia , Theileria parva/isolamento & purificação , Theileriose/transmissão
17.
J S Afr Vet Assoc ; 79(3): 116-20, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19244819

RESUMO

The purpose of this study was to determine the species spectrum of ticks infesting goats owned by resource-limited farmers in the state-owned communal land areas of Zimbabwe. Ticks were collected from goats at a single locality within each of 5 communal land areas, and a total of 14 ixodid tick species was recovered. The most numerous tick was Rhipicephalus evertsi evertsi, which was present in all areas at each sampling, and a Rhipicephalus sp. (near R. punctatus), which was most abundant on goats in the central regions of Zimbabwe during the March rainy season. Amblyomma hebraeum was present on goats in all areas sampled. In the eastern central region its distribution overlapped that of Amblyomma variegatum, while in the northwest it overlapped those of both Amblyomma marmoreum and A. variegatum. Hyalomma truncatum was present at all localities, whereas only a single Hyalomma rufipes was recovered. Rhipicephalus appendiculatus was collected from goats in the moist, slightly cooler regions, while the few Rhipicephalus zambeziensis recovered were present in the hotter, drier regions. Species recorded in lower numbers were Rhipicephalus (Boophilus) decoloratus, Rhipicephalus lunulatus, Rhipicephalus simus, Rhipicephalus tricuspis and Rhipicephalus turanicus. Attachment in the inter-digital space of adult A. hebreaum and H. truncatum was sometimes associated with lameness.


Assuntos
Doenças das Cabras/parasitologia , Ixodidae/classificação , Filogenia , Infestações por Carrapato/veterinária , Animais , Feminino , Doenças das Cabras/epidemiologia , Cabras , Ixodidae/crescimento & desenvolvimento , Masculino , Estações do Ano , Controle de Ácaros e Carrapatos , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/parasitologia , Zimbábue/epidemiologia
18.
Zoonoses Public Health ; 54(1): 23-30, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17359443

RESUMO

Bovine anaplasmosis, caused by the tick-borne rickettsia Anaplasma marginale, is endemic in South Africa and results in considerable economic loss to the cattle industry. This study was designed to characterize strains of A. marginale at the molecular level from cattle raised in communal and commercial farms in the north-eastern and south-western regions of the Free State Province, South Africa, that varied in rainfall and vegetation. Seroprevalence to A. marginale was determined in 755 cattle by an Anaplasma spp. competitive enzyme-linked immunosorbent assay and ranged from 44% to 98% and was similar in both regions. While Anaplasma centrale was not targeted in this study, A. marginale infections were identified by species-specific msp1alpha polymerase chain reaction in 129 of 215 of the samples studied. Similar genetic diversity of A. marginale strains was found in both the north-eastern and south-western regions. The sequences of 29 A. marginalemsp1alpha amplicons from South African strains revealed considerable genetic diversity providing 14 new repeat sequences. However, 42% of MSP1a repeat sequences were not unique to this region. These results indicated the presence of common genotypes between South African, American and European strains of A. marginale. Cattle movement between different parts of South Africa was suggested by the presence of identical A. marginale MSP1a genotypes in north-eastern and south-western regions of the Free State Province. Control strategies for anaplasmosis in South Africa should therefore be designed to be protective against genetically heterogeneous strains of A. marginale.


Assuntos
Anaplasma marginale/genética , Anaplasma marginale/imunologia , Anaplasmose/epidemiologia , Doenças dos Bovinos/epidemiologia , Variação Genética , Anaplasma marginale/isolamento & purificação , Anaplasmose/microbiologia , Animais , Anticorpos Antibacterianos/sangue , Sequência de Bases , Bovinos , Doenças dos Bovinos/microbiologia , DNA Bacteriano/análise , Feminino , Genótipo , Masculino , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase/métodos , Reação em Cadeia da Polimerase/veterinária , Estudos Soroepidemiológicos , África do Sul/epidemiologia , Especificidade da Espécie
19.
Artigo em Inglês | MEDLINE | ID: mdl-15589399

RESUMO

There is evidence from our own laboratory and that of others that EP-receptor ligands are strong contractile agonists in bovine iris sphincter and that FP-receptor agonists are strong contractile agonists in cat iris sphincter. Here, we have investigated the effects of prostaglandin (PG) receptor agonists of the FP-, EP-, TP- and DP-class on myosin light chain (MLC) phosphorylation, p42/p44 MAP kinase phosphorylation and contraction in the iris sphincter of bovine and cat. Using three signal transduction mechanism assays, namely MLC phosphorylation, MAP kinase phosphorylation and contraction, we demonstrated that in bovine iris sphincter the rank order of potency of the PG agonists in the contractile and MLC phosphorylation assays is as follows: E2>U46619>F2alpha>D2, and in cat F2alpha>D2>E2>U46619. In the MAP kinase assay, in bovine iris sphincter the rank order of potency is E2>F2alpha and in cat F2alpha>E2. These conclusions are supported by the following findings: (1) In the contractile assay, in the bovine sphincter the EC50s for PGF2alpha, PGE2, U46619 and PGD2 were found to be 1.4x10(-7), 5.0x10(-9), 9.0x10(-9) and 1.3x10(-6)M, respectively, and the corresponding values in the cat were 1.9x10(-8), 2.3x10(-7), 1.5x10(-6) and 6.9x10(-8)M, respectively. (2) In the MLC phophorylation assay, in the bovine sphincter PGF2alpha, PGE2, U46619 and PGD2 increased MLC phophorylation by 118%, 165%, 153% and 72%, respectively, and the corresponding values in cat were 175%, 99%, 90% and 95%, respectively. (3) In the MAP kinase assay, in the bovine iris sphincter PGF2alpha and PGE2, increased MAP kinase phosphorylation by 276% and 328%, respectively, and the corresponding values in cat were 308% and 245%, respectively. The data presented demonstrate pronounced species differences in the effects of the prostanoids on the MLC kinase signaling pathway in bovine and cat irides and furthermore confirm the existence of FP-receptors in that of the bovine.


Assuntos
MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Iris/fisiologia , Cadeias Leves de Miosina/metabolismo , Prostaglandinas/farmacologia , Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/farmacologia , Animais , Gatos , Bovinos , Dinoprosta/farmacologia , Dinoprostona/farmacologia , Iris/efeitos dos fármacos , Latanoprosta , Contração Muscular/efeitos dos fármacos , Contração Muscular/fisiologia , Músculo Liso/efeitos dos fármacos , Músculo Liso/fisiologia , Fosforilação , Prostaglandinas F Sintéticas/farmacologia , Especificidade da Espécie
20.
Australas Phys Eng Sci Med ; 27(1): 11-5, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15156702

RESUMO

It is known that movements of the right side of the body are controlled by the left motor cortex of the brain. The aim of this study is to evaluate the contribution of right motor cortex of the brain in the central motor control of right-sided muscle contraction. EEG/EEG coherence analysis has been used to determine the functional coupling between the right and left motor cortical areas in twenty normal volunteers, during maximum voluntary contraction (MVC) and 50% MVC of right Adductor Pollicis muscle (APM). It shows that the maximum mean coherence values were: 0.751 during MVC at 10 and 12 Hz, and 0.274 during 50% of MVC at 22 Hz. The minimum mean coherence values were: 0.716 during MVC at 48 and 50 Hz, and 0.242 during 50% MVC at 34 Hz. The high coherence values obtained during MVC, and to a lesser extent during 50% of MVC, could be attributed to the need of recruitment of both motor cortical areas during the decision phase of central motor control of voluntary muscular contraction. The "will" to perform maximum voluntary contraction could be a major factor, which contribute to the higher coherence values obtained during MVC than these associated with 50% of MVC.


Assuntos
Diagnóstico por Computador/métodos , Eletroencefalografia/métodos , Contração Isométrica/fisiologia , Córtex Motor/fisiologia , Movimento/fisiologia , Músculo Esquelético/fisiologia , Esforço Físico/fisiologia , Volição/fisiologia , Adulto , Algoritmos , Mapeamento Encefálico/métodos , Feminino , Humanos , Masculino , Estatística como Assunto , Polegar/fisiologia
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