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1.
Malays J Pathol ; 45(3): 397-403, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38155381

RESUMO

A rapid and accurate diagnosis of invasive fungal infections (IFIs) has been a great challenge particularly in cases requiring prompt antifungal treatment. In this study, four primer pairs were designed for a quadruplex PCR assay, which was developed for detection of four fungal species simultaneously. DNA extraction of cultured colonies and spiked blood samples were performed using conventional (phenol-chloroform) techniques and commercial DNA extraction kit. The optimum annealing temperature for this assay was 60°C. The assay was able to amplify all four genes and showed 100% specificity. No amplification of any genes was obtained against other species (n=14), which included two bacteria species. In conclusion, this quadruplex PCR assay is specific, rapid and reliable to detect A. fumigatus, A. terreus, C. albicans and C. glabrata simultaneously.


Assuntos
Aspergillus fumigatus , Infecções Fúngicas Invasivas , Humanos , Aspergillus fumigatus/genética , Candida albicans/genética , Candida glabrata/genética , Candida/genética , Reação em Cadeia da Polimerase/métodos , DNA , Sensibilidade e Especificidade
2.
ISA Trans ; 141: 470-481, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37507325

RESUMO

In this paper, the energy efficiency of the widespread application of backstepping control to a class of nonlinear motion systems is investigated. A Switched Step Integral Backstepping Control (SSIBC) scheme is introduced to improve immunity to measurement noise and to increase the energy efficiency of conventional backstepping in practice. The SSIBC is realized by switching between two candidate controllers obtained at different steps of the iterative backstepping design process. A bi-state dependent hysteresis rule is developed to supervise stable switching between the different regimes in the presence of noise. The proposed method is experimentally verified on a MIMO twin rotor laboratory helicopter involving coupled nonlinear dynamics, inaccessible states and uncertainties. Experimental results show that in addition to a reduction in power consumption, the SSIBC reduces saturation of the control signal and visible motor jerking in contrast with conventional backstepping. Additional comparisons with a previously proposed optimized decoupling PID controller also show significant improvement in precision achieved with higher energy efficiency. Experimental results obtained with the introduction of an external disturbance into the system also show the robustness of the proposed SSIBC.

3.
West Afr J Med ; 40(6): 581-589, 2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37384609

RESUMO

BACKGROUND: Typical ageing changes and the associated health concerns frequently manifest themselves as reduction in their efficiency and functional capacity. OBJECTIVE: To identify the socioeconomic and lifestyle determinants of the functional capacity of elderly patients. METHODS: A cross-sectional study involving 329 patients aged ≥ 60 years who presented to the General Outpatient Clinic. Data on socioeconomic, lifestyle, and functional capacity were collected. The functional capacity was assessed by the self-reported questionnaires: the Lawton and Katz indexes for the activity of daily living (ADL) and instrumental activity of daily living (IADL) respectively. The chi-square test and logistic regression analysis were used to determine associations between the variables. The level of significance was set at a p-value ≤ 0.05. RESULTS: A total of 312 respondents completed the study, with 59.6% females and a mean age of 67.67 ± 7.69 years. The majority of the respondents (76.3%) belong to the low socioeconomic status (classes V and VI). The prevalence of functional dependence was 21.5% and 44.2% for ADL and IADL respectively. The disability in continence and food preparation had the highest prevalence among the components of ADL and IADL respectively. Advancing age, Hausa/Fulani tribe, polygamy, poor social support, and chronic pain were the determinants of functional dependence in ADL while age, female gender, marital status, and Fulani tribe were the determinants of functional dependence in IADL among the respondents.CONCLUSION: The identified determinants of functional capacity among the older persons should be considered when assessing their functional capacity in the primary care or similar settings.


CONTEXTE: Les changements typiques liés au vieillissement et les problèmes de santé qui y sont associés se manifestent souvent par une réduction de l'efficacité et de la capacité fonctionnelle. OBJECTIFS: Identifier les déterminants socio-économiques et le mode de vie de la capacité fonctionnelle des patients âgés. MÉTHODES: Étude transversale portant sur 329 patients âgés de ≥ 60 ans qui se sont présentés à la consultation externe générale. Des données sur la situation socio-économique, le mode de vie et la capacité fonctionnelle ont été recueillies. La capacité fonctionnelle a été évaluée à l'aide de questionnaires autodéclarés : les indices de Lawton et de Katz pour l'activité de la vie quotidienne (ADL) et l'activité instrumentale de la vie quotidienne (IADL) respectivement. Le test du chi carré et l'analyse de régression logistique ont été utilisés pour déterminer les associations entre les variables. Le niveau de signification a été fixé à une valeur p ≤ 0,05. RÉSULTATS: Au total, 312 personnes ont répondu à l'étude, dont 59,6 % de femmes et un âge moyen de 67,67 ±7,69 ans. La majorité des personnes interrogées (76,3 %) appartiennent à un statut socioéconomique faible (classes V et VI). La prévalence de la dépendance fonctionnelle était de 21,5 % et 44,2 % pour les AVQ et les AIVQ respectivement. Les incapacités liées à la continence et à la préparation des repas ont la prévalence la plus élevée parmi les composantes des AVQ et des AIVQ respectivement. L'âge avancé, la tribu Hausa/Fulani, la polygamie, le manque de soutien social et la douleur chronique étaient les déterminants de la dépendance fonctionnelle dans les AVQ, tandis que l'âge, le sexe féminin, l'état matrimonial et la tribu Fulani étaient les déterminants de la dépendance fonctionnelle dans les AIVQ parmi les personnes interrogées. CONCLUSION: Les déterminants identifiés de la capacité fonctionnelle chez les personnes âgées devraient être pris en compte lors de l'évaluation de leur capacité fonctionnelle dans le cadre des soins primaires ou dans des contextes similaires. Mots clés: Capacité fonctionnelle, Socio-économie, Mode de vie, Personnes âgées et nord du Nigeria.


Assuntos
Instituições de Assistência Ambulatorial , Estilo de Vida , Idoso , Humanos , Feminino , Idoso de 80 Anos ou mais , Pessoa de Meia-Idade , Masculino , Estudos Transversais , Nigéria/epidemiologia , Baixo Nível Socioeconômico
4.
Trop Biomed ; 39(1): 11-16, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35225295

RESUMO

Trimethoprim-sulfamethoxazole is an active agent against Burkholderia pseudomallei and is being used in intensive and maintenance phases of melioidosis therapy. In this study, we evaluated the bactericidal activities of ß-lactams (imipenem, ceftazidime and amoxicillin- clavulanate) alone and in combinations with trimethoprim-sulfamethoxazole against B. pseudomallei . Four clinical strains of B. pseudomallei were selected based on different genotypes that are frequently found in Malaysia. The minimum inhibitory concentrations of trimethoprim-sulfamethoxazole, ceftazidime, imipenem and amoxicillin-clavulanate were determined using microdilution broth method. The bactericidal activities and synergy effects of ß-lactams and/or trimethoprim-sulfamethoxazole were evaluated by checkerboard and static time-kill analyses at 1×MIC concentration of each antibiotic. Using checkerboard method, the ß-lactam/trimethoprim-sulfamethoxazole combinations exhibited ΣFIC of 0.75-4.00. In time-kill analysis, ceftazidime/trimethoprim-sulfamethoxazole combination demonstrated synergy against three strains (less 2.25-2.41 log 10 CFU/mL compared to the most active antibiotic monotherapy) whereas imipenem/trimethoprim-sulfamethoxazole combination regimen showed synergy against one strain (less 3.32 log 10 CFU/mL). No antagonist effect or major re-growth was observed in all combination regimens, whereas 11 out of 12 of ß-lactam monotherapy regimens were associated with re-growth of bacteria. However, all ß-lactam monotherapy regimens exhibited rapid and stronger killing activities against BUPS/07/14, in the initial 12 hours compared to ß-lactam/ trimethoprim- sulfamethoxazole combination regimens. The combination of ß-lactams with trimethoprim- sulfamethoxazole demonstrated better killing effect at 24 hours compared to monotherapy and no major bacterial regrowth was observed. Nevertheless, delay in killing activities of ß-lactam/trimethoprim-sulfamethoxazole combination regimens against BUPS/07/14 need further examination because this phenomenon can lead to treatment failure in some patients.


Assuntos
Antibacterianos , Burkholderia pseudomallei , Combinação Trimetoprima e Sulfametoxazol , Amoxicilina/farmacologia , Antibacterianos/farmacologia , Burkholderia pseudomallei/efeitos dos fármacos , Ceftazidima/farmacologia , Ácido Clavulânico/farmacologia , Imipenem/farmacologia , Malásia , Testes de Sensibilidade Microbiana , Combinação Trimetoprima e Sulfametoxazol/farmacologia
5.
Tropical Biomedicine ; : 11-16, 2022.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-936392

RESUMO

@#Trimethoprim-sulfamethoxazole is an active agent against Burkholderia pseudomallei and is being used in intensive and maintenance phases of melioidosis therapy. In this study, we evaluated the bactericidal activities of β-lactams (imipenem, ceftazidime and amoxicillinclavulanate) alone and in combinations with trimethoprim-sulfamethoxazole against B. pseudomallei. Four clinical strains of B. pseudomallei were selected based on different genotypes that are frequently found in Malaysia. The minimum inhibitory concentrations of trimethoprim-sulfamethoxazole, ceftazidime, imipenem and amoxicillin-clavulanate were determined using microdilution broth method. The bactericidal activities and synergy effects of β-lactams and/or trimethoprim-sulfamethoxazole were evaluated by checkerboard and static time-kill analyses at 1×MIC concentration of each antibiotic. Using checkerboard method, the β-lactam/trimethoprim-sulfamethoxazole combinations exhibited ΣFIC of 0.75-4.00. In time-kill analysis, ceftazidime/trimethoprim-sulfamethoxazole combination demonstrated synergy against three strains (less 2.25-2.41 log10CFU/mL compared to the most active antibiotic monotherapy) whereas imipenem/trimethoprim-sulfamethoxazole combination regimen showed synergy against one strain (less 3.32 log10CFU/mL). No antagonist effect or major re-growth was observed in all combination regimens, whereas 11 out of 12 of β-lactam monotherapy regimens were associated with re-growth of bacteria. However, all β-lactam monotherapy regimens exhibited rapid and stronger killing activities against BUPS/07/14, in the initial 12 hours compared to β-lactam/ trimethoprimsulfamethoxazole combination regimens. The combination of β-lactams with trimethoprimsulfamethoxazole demonstrated better killing effect at 24 hours compared to monotherapy and no major bacterial regrowth was observed. Nevertheless, delay in killing activities of β-lactam/trimethoprim-sulfamethoxazole combination regimens against BUPS/07/14 need further examination because this phenomenon can lead to treatment failure in some patients.

6.
Carbohydr Res ; 509: 108436, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34507178

RESUMO

Two new glucosamines, Microphyllose A and B were isolated from the chloroform fraction of Neocarya macrophylla fruit using flash column chromatography. The structures of these compounds were elucidated based on chemical tests and the analysis of their spectral data (IR, 1D- & 2D-NMR). The compounds have demonstrated significant (p < 0.05) antivenom activity against Naja nigricollis venom with 60 and 80% protection, respectively. When subjected to molecular docking, the compounds have demonstrated different binding affinities against three toxins (phospholipase A2, neurotoxin and cardiotoxin) from Naja nigricollis venom and they were further screened for ADMET analysis based on Lipinski's and Veber's rule and the compounds have failed absorptivity for oral medications. To the best of our knowledge, this is the first report of isolation and molecular docking analysis of these compounds from medicinal plants.


Assuntos
Frutas
8.
Trop Biomed ; 38(1): 183-186, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33797544

RESUMO

Spontaneous bacterial peritonitis caused by Vibrio cholerae non-O1/ non-O139 is a rare phenomenon. V. cholerae is known as a common aetiology of epidemic diarrheal disease and rarely causes extra-gastrointestinal infections. In this report, a 52-year-old man presented to our hospital with a clinical scenario for chronic liver cirrhosis with low grade fever and loose stools. V. cholerae was isolated from peritoneal fluid culture, which was further confirmed as non-O1/ non-O139 strain by multiplex polymerase chain reaction. The patient was successfully treated with antimicrobial therapy and peritoneal drainage. This case represents the first isolation of V. cholerae non-O1/ non-O139 strain from peritoneal fluid.


Assuntos
Cólera/microbiologia , Cirrose Hepática/complicações , Peritonite/microbiologia , Vibrio cholerae não O1 , Cólera/complicações , Humanos , Masculino , Pessoa de Meia-Idade
9.
Phys Med ; 82: 163-170, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33640836

RESUMO

Hard X-ray radiation with high brightness and high fluxes is nowadays available on the fourth generation of synchrotrons and X-FELs, but the large size and complexity of these sources makes its use difficult for widespread applications. New table top X-ray sources driven by ultrashort high power lasers offer a compelling route to expand the availability of hard X-ray sources. They can be used for advanced imaging techniques, due to its small source size and spatial coherence. We present in this paper the validation of a compact laser-driven X-ray microfocus source for high-resolution radiography imaging. This novel device was built at the Laser Laboratory for Acceleration and Applications (L2A2) at the University of Santiago de Compostela. This paper describes the laser-plasma X-ray source with improved stability and characterize some of its properties. We demonstrate the high-contrast and resolution of the images obtained with this source by using masks with well known geometries, and detailed analysis by using the modulation transfer function. Finally, we discuss the properties of this source in comparison to other compact microfocus X-ray sources.


Assuntos
Lasers , Luz , Radiografia , Síncrotrons , Raios X
10.
J Clin Hypertens (Greenwich) ; 23(4): 785-792, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33471442

RESUMO

A chronic disease management model of care (Empower Health) was launched in rural and urban areas of Ghana and Kenya in 2018. The goal was to improve disease awareness, reduce the burden of disease, and improve the clinical effectiveness and efficiency of managing hypertension. Leveraging the model, clinicians provide patients with tailored management plans. Patients accessed regular blood pressure checks at home, at the clinic, or at community-partner locations where they received real-time feedback. On the mobile application, clinicians viewed patient data, provided direct patient feedback, and wrote electronic prescriptions accessible through participating pharmacies. To date, 1266 patients had been enrolled in the "real-world" implementation cohort and followed for an average of 351 ± 133 days across 5 facilities. Average baseline systolic blood pressure (SBP) was 145 ± 21 mmHg in the overall cohort and 159 ± 16 mmHg in the subgroup with uncontrolled hypertension (n = 743) as defined by baseline SBP ≥ 140 mmHg. SBP decreased significantly through 12 months in both the overall cohort (-9.4 mmHg, p < .001) and in the uncontrolled subgroup (-17.6 mmHg, p < .001). The proportion patients with controlled pressure increased from 46% at baseline to 77% at 12 months (p < .001). In summary, a new chronic disease management model of care improved and sustained blood pressure control to 12 months, especially in those with elevated blood pressure at enrollment.


Assuntos
Hipertensão , Pressão Sanguínea , Gerenciamento Clínico , Gana/epidemiologia , Humanos , Hipertensão/diagnóstico , Hipertensão/tratamento farmacológico , Hipertensão/epidemiologia , Resultado do Tratamento
11.
Tropical Biomedicine ; : 183-186, 2021.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-886634

RESUMO

@#Spontaneous bacterial peritonitis caused by Vibrio cholerae non-O1/ non-O139 is a rare phenomenon. V. cholerae is known as a common aetiology of epidemic diarrheal disease and rarely causes extra-gastrointestinal infections. In this report, a 52-year-old man presented to our hospital with a clinical scenario for chronic liver cirrhosis with low grade fever and loose stools. V. cholerae was isolated from peritoneal fluid culture, which was further confirmed as non-O1/ non-O139 strain by multiplex polymerase chain reaction. The patient was successfully treated with antimicrobial therapy and peritoneal drainage. This case represents the first isolation of V. cholerae non-O1/ non-O139 strain from peritoneal fluid.

12.
PLoS Med ; 17(9): e1003218, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32903257

RESUMO

BACKGROUND: A decade of Boko Haram insurgency brought conflict, mass displacement, and the destruction of basic infrastructure to Northeast Nigeria. Over 2 million internally displaced persons (IDPs) suffering from lack of basic hygienic conditions, malnutrition, and disease live in camps or are hosted by communities in the region, where the conflict has contributed to a massive destruction of health facilities. Infectious diseases like tuberculosis (TB) and HIV are especially difficult to address under such conditions, and IDPs are vulnerable to both. Although international investment supports some health interventions among IDPs, locally sourced solutions are lacking. METHODS AND FINDINGS: We evaluated the impact of an active case finding (ACF) intervention for TB and testing for HIV in IDP communities and provided linkages to treatment in 3 states in Northeast Nigeria: Adamawa, Gombe, and Yobe. The ACF was a component of a multistakeholder collaboration between government, civil society, and IDP community partners, which also included mapping of IDP populations and health services, supporting existing health facilities, developing a sample transport network, and organizing community outreach to support ACF. Between July 1, 2017, and June 30, 2018, ACF was conducted in 26 IDP camps and 963 host communities in 12 local government areas (LGAs) with another 12 LGAs serving as a control population. Outreach efforts resulted in 283,556 screening encounters. We screened 13,316 children and 270,239 adults including 150,303 (55.6%) adult women and 119,936 (44.4%) men. We tested 17,134 people for TB and 58,976 for HIV. We detected 1,423 people with TB and 874 people living with HIV. We linked 1,419 people to anti-TB treatment and 874 people with HIV to antiretroviral treatment sites. We evaluated additional TB cases notified and conducted comparative interrupted time series (ITS) analyses to assess the impact of ACF on TB case notifications. Through our efforts, bacteriologically confirmed TB notifications increased by 847 (45.1%) during the intervention period, with IDPs accounting for 46% of these notifications. The ITS analyses detected significant positive postintervention trend differences in TB notification rates between the intervention and control areas in all forms TB (incidence rate ratio [IRR] = 1.136 [1.072, 1.204]; p ≤ 0.001) and bacteriologically positive TB (IRR = 1.141 [1.058, 1.229]; p = 0.001). The TB prevalence (502 cases per 100,000 screening encounters) was 10 times the national notification rates and 2.3 times the estimated national incidence. Rates of HIV infection (1.8%) were higher than HIV prevalence estimates in the 3 states. Our study was limited by the nonrandom selection of LGAs. Furthermore, we did not use sensitive screening tools like chest X-ray and likely missed people with TB. CONCLUSIONS: In this study, we observed a burden of TB in IDP populations of Northeast Nigeria many times higher than national rates and HIV rates higher than state level estimates. The impact of the intervention showed that ACF can greatly increase TB case notifications. Engaging IDP communities, local governments, and civil society organizations is essential to ensuring the success of interventions targeting TB and HIV, and such approaches can provide sustained solutions to these and other health crises among vulnerable populations.


Assuntos
Intervenção Médica Precoce/métodos , Infecções por HIV/epidemiologia , Tuberculose/epidemiologia , Adolescente , Adulto , Criança , Relações Comunidade-Instituição , Feminino , Instalações de Saúde , Humanos , Incidência , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Nigéria/epidemiologia , Prevalência , Refugiados , Adulto Jovem
13.
Sci Rep ; 10(1): 3931, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32127554

RESUMO

Understanding and extending the predictability of El Niño‒Southern Oscillation (ENSO) has been an important research topic because of ENSO's large influence on global weather and climate. Here, we develop an empirical model of tropical atmosphere-ocean interactions that has high ENSO prediction skill, comparable to the skills of well performing dynamical models. The model is used to investigate the effects of the main atmosphere-ocean interaction processes-thermocline and zonal wind feedbacks and zonal wind forcing-on its ENSO predictability. We find that all these processes significantly affect ENSO predictability and extend the predictability limit by up to four months, with the largest effect coming from the thermocline feedback followed by the total zonal wind forcing. The other processes with progressively smaller effects are the external zonal wind forcing and zonal wind feedback. The two most influential processes, however, affect ENSO predictability in the VAR model differently. The thermocline feedback improves the forecast skill by predominantly maintaining the correct phase, whereas the total zonal wind forcing improves the skill by maintaining the correct amplitude of the forecast ENSO events. This result suggests that the dynamical seasonal prediction models must have good representations of the major ENSO processes to make skilful ENSO predictions.

14.
Heliyon ; 6(1): e03237, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32042971

RESUMO

The studies of advanced materials in environmental remediation and degradation of pollutants is rapidly advancing because of their wide varieties of applications. BiFeO3 (BFO), a perovskite nanomaterial with a rhombohedral R3c space group, is currently receiving tremendous attention in photodegradation of dyes. The photocatalytic activity of BFO nanoparticle is a promising field of research in photocatalysis. BFO nanomaterial is a photocatalyst enhanced by doping because of its reduce bandgap energy (2.0-2.77 eV), multiferroic property, strong photoabsorption and crystal structure. The material has proven to be very useful for the degradation of dyes under visible light irradiation among other photocatalysts. Its exceptional nontoxicity, suitability, low cost and long term excellent stability makes it an efficient photocatalyst for the degradation of effluents from textile and pharmaceutical industries which ended-up in the environment and now a major concern of the modern world. This mini-review attempts to provide some detailed synthetic routes of BFO and BFO related nanomaterials and the notable achievements so far on the effect of doping the material. It also discusses the effect of crystallite size of the material and other photophysical properties and how they influence the photocatalytic process of model organic dye pollutants, to date.

15.
Trop Biomed ; 37(4): 903-910, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33612744

RESUMO

Candida parapsilosis is an important pathogen of healthcare-associated bloodstream infections (BSI) causing high mortality and morbidity in immunocompromised patients in addition to other Candida species including C. albicans, C. tropicalis, C. glabrata, and C. krusei. Knowledge on recent local species distribution and trend is essential. An increase in the proportion of C. parapsilosis candidemia has been recently observed as a result of many risk factors. The distribution of candidemia has been changing in the last three decades. To determine the proportion of different Candida species causing candidemia in a tertiary-care hospital during January 2001 - December 2018, a retrospective study performed in a 853-bedded tertiary-care hospital in north-eastern Malaysia. All cases of candidemia from January-2001 to December-2018 were included, and the review was performed based on patients' medical records and laboratory database. The frequency of different Candida species was determined. This study showed that out of 1175 patients with candidemia, C. parapsilosis was the most common species contributing to 29.2% (343/1175) of candidemia, followed by C. albicans 20.1% (236/1175), C. tropicalis 18.7% (220/1175), C. glabrata 6.0% (71/1175), C. guilliermondii 3.7% (43/1175), C. rugosa 1.9% (22/1175), C. famata 1.7% (20/1175), C. krusei 1.4% (16/1175), C. dubliniensis 0.8% (9/1175), C. lusitaniae 0.7% (8/1175), C. lipolytica 0.3% (4/1175), C. pelliculosa 0.3% (4/1175), C. haemulonii, C. kefyr, C. utilis and C. inconspicua (1/1175 each). In addition, 14.9% (175/1175) belonged to Candida spp. which were not identified to species level. In conclusion, a different scenario for the proportion of Candida species with C. parapsilosis predominates over C. albicans as a nosocomial pathogen leading to candidemia has been shown in this study.


Assuntos
Candida parapsilosis/isolamento & purificação , Candidemia/epidemiologia , Candida/classificação , Candida/isolamento & purificação , Candidemia/microbiologia , Estudos Transversais , Humanos , Malásia/epidemiologia , Estudos Retrospectivos , Centros de Atenção Terciária
16.
Trop Biomed ; 37(3): 783-790, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33612791

RESUMO

Reduced susceptibility in Burkholderia pseudomallei during carbapenem therapy may lead to treatment failure. We isolated a clinical strain that had developed reduced susceptibility to carbapenems while on treatment. After reviewing the patient's clinical notes, the initial isolate (BUPS01/14) was exposed to carbapenem in vitro to mimic the clinical scenario. The stability of susceptibility of the carbapenem-exposed strain (BUPS01/14R) was examined by serial subculture in antibiotic-free broth. Biochemical and morphological comparison was performed by the VITEK® system and electron microscopy. MICs increased 32-fold following carbapenem exposure and became stable in the antibiotic-free environment. On electron microscopic examination, the BUPS01/14R cells were smoother and less wrinkled compared to BUPS01/14 cells. This report highlights a potential anti-melioidosis treatment failure due to the emergence of resistance while on carbapenem monotherapy. Further study of this strain is necessary to understand the mechanism of resistance at a molecular level.


Assuntos
Burkholderia pseudomallei/efeitos dos fármacos , Carbapenêmicos/farmacologia , Farmacorresistência Bacteriana , Carbapenêmicos/uso terapêutico , Evolução Fatal , Humanos , Masculino , Melioidose/tratamento farmacológico , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade
17.
ISA Trans ; 97: 1-13, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31327468

RESUMO

This paper proposes an improved method of integral backstepping for real time control of a laboratory helicopter with variable speed rotors known as the Two-Rotor Aero-dynamic System (TRAS). The coupled system is decomposed into the horizontal subsystem (HS) and the vertical subsystem (VS) and traditional backstepping, augmented with direct integral action is designed for each subsystem. The transient response to both constant and time varying references is then simultaneously improved by modifying an already proposed method called dual boundary conditional integration. A switching technique is also employed to enhance the tracking response of the undamped HS for its bi-directional motor which exhibits jerking effects. Experimental results show that the proposed approach yields improved transient and tracking performance when compared to previously proposed methods exploiting conditional integration earlier proposed for improving the transient response of controlled nonlinear systems with integral action. The results also show the robustness of the proposed method in the presence of the coupling effects and additional external disturbance applied to the system in the form of a wind gust.

18.
Tropical Biomedicine ; : 783-790, 2020.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-825632

RESUMO

@#Reduced susceptibility in Burkholderia pseudomallei during carbapenem therapy may lead to treatment failure. We isolated a clinical strain that had developed reduced susceptibility to carbapenems while on treatment. After reviewing the patient’s clinical notes, the initial isolate (BUPS01/14) was exposed to carbapenem in vitro to mimic the clinical scenario. The stability of susceptibility of the carbapenem-exposed strain (BUPS01/14R) was examined by serial subculture in antibiotic-free broth. Biochemical and morphological comparison was performed by the VITEK® system and electron microscopy. MICs increased 32-fold following carbapenem exposure and became stable in the antibiotic-free environment. On electron microscopic examination, the BUPS01/14R cells were smoother and less wrinkled compared to BUPS01/14 cells. This report highlights a potential anti-melioidosis treatment failure due to the emergence of resistance while on carbapenem monotherapy. Further study of this strain is necessary to understand the mechanism of resistance at a molecular level.

19.
Tropical Biomedicine ; : 903-910, 2020.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-862403

RESUMO

@#. Candida parapsilosis is an important pathogen of healthcare-associated bloodstream infections (BSI) causing high mortality and morbidity in immunocompromised patients in addition to other Candida species including C. albicans, C. tropicalis, C. glabrata, and C. krusei. Knowledge on recent local species distribution and trend is essential. An increase in the proportion of C. parapsilosis candidemia has been recently observed as a result of many risk factors. The distribution of candidemia has been changing in the last three decades. To determine the proportion of different Candida species causing candidemia in a tertiary-care hospital during January 2001 – December 2018, a retrospective study performed in a 853-bedded tertiary-care hospital in north-eastern Malaysia. All cases of candidemia from January-2001 to December-2018 were included, and the review was performed based on patients’ medical records and laboratory database. The frequency of different Candida species was determined. This study showed that out of 1175 patients with candidemia, C. parapsilosis was the most common species contributing to 29.2% (343/1175) of candidemia, followed by C. albicans 20.1% (236/1175), C. tropicalis 18.7% (220/1175), C. glabrata 6.0% (71/1175), C. guilliermondii 3.7% (43/1175), C. rugosa 1.9% (22/1175), C. famata 1.7% (20/1175), C. krusei 1.4% (16/1175), C. dubliniensis 0.8% (9/1175), C. lusitaniae 0.7% (8/1175), C. lipolytica 0.3% (4/1175), C. pelliculosa 0.3% (4/1175), C. haemulonii, C. kefyr, C. utilis and C. inconspicua (1/1175 each). In addition, 14.9% (175/1175) belonged to Candida spp. which were not identified to species level. In conclusion, a different scenario for the proportion of Candida species with C. parapsilosis predominates over C. albicans as a nosocomial pathogen leading to candidemia has been shown in this study

20.
Heliyon ; 5(7): e01927, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31317078

RESUMO

This research is aimed at delineating the groundwater potential zones in Gombe and environs using Dar Zarrouk parameters. The study area is located within longitudes 11°7'0″E to 11°14'0″E, and latitudes 10°15'0″N to 10°21'0″N, it is basically underlain by basement Complex rocks represented by Diorite and Granites, and Cretaceous sedimentary rocks represented by Bima, Yolde, Fika and Gombe Formations. Thirty two (32) vertical electric soundings (VES) using Schlumberger array method with the aid of ABEM Signal Averaging System (SAS) Terrameter was used for the data acquisition. The result of the interpretation shows four to six geo-electric layers. The geo-electric section revealed the major aquifers to be confined and semi confined and consist of Medium grain sandstones, with varying thicknesses. The aquifer hydraulic characteristics indicated that the transverse resistance, ranges from 235.2Ωm2 to 6317.87Ωm2 with an average value of 1789.50Ωm2. The Longitudinal conductance, S, ranges from 0.1415Ωm to 31.933Ωm with an average of 2.002Ωm. The Hydraulic conductivity value range from 2.62m/day to 138.66 m/day with a mean value of 20.662 m/day. The transmissivity values obtained for the various layers range from 78.34 m2/day to 13284.02m2/day, with the average value been 893.57 m2/day. Four groundwater potential zones were delineated including medium grain sandstones, Sandstones, clayey sand and shaly sand.

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