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1.
JAMA Netw Open ; 7(6): e2413004, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38833253

RESUMEN

Importance: It is essential to identify inequitable cancer care for ethnic minority groups, which may allow policy change associated with improved survival and decreased mortality and morbidity. Objective: To investigate ethnic disparities in survival and mortality among New Zealand (NZ) patients with head and neck cancer (HNC) and the association of other variables, including socioeconomic status, tumor stage, and age at diagnosis, with survival rates. Design, Setting, and Participants: This retrospective cohort study was conducted among NZ patients diagnosed with specific HNCs from 2010 to 2020. Anonymized data were obtained from the NZ Cancer Registry, including patients diagnosed from International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10) codes C00-C14 and C30-C32. Data were analyzed from July 2020 through January 2024. Main Outcomes and Measures: Censored Kaplan-Meier estimates were used to analyze survival distribution. Cox regression models were used to estimate the association of age, tumor stage at diagnosis, and socioeconomic status with survival rates. Age-standardized mortality rates were assessed. Results: Among 6593 patients with HNCs (4590 males [69.6%]; 4187 patients aged 51-75 years [63.5%]), there were 706 Maori individuals (10.7%) and 5887 individuals with other ethnicity (89.3%), including 4327 NZ European individuals (65.6%; defined as New Zealanders of European descent). Maori individuals had a decreased survival proportion at all years after diagnosis compared with individuals with other ethnicity (eg, 66.1% [95% CI, 62.6%% to 69.8%] vs 71.2% [95% CI, 70.0% to 72.4%] at 2 years). At 1 year after diagnosis, Maori individuals did not have a significantly increased mortality rate compared with 5795 individuals with other ethnicity with data (193 deaths [27.3%] vs 1400 deaths [24.2%]; P = .06), but the rate was significantly increased at 5 years after diagnosis (277 deaths [39.3%] vs 2034 deaths [35.1%]; P = .03); there was greater disparity compared with NZ European individuals (1 year: 969 deaths [22.4%]; P = .003; 5 years: 1441 deaths [33.3%]; P = .002). There were persistent age-adjusted mortality rate disparities: 40.1% (95% CI, -25.9% to 71.2%) for Maori individuals and 18.8% (95% CI, -15.4% to 24.4%) for individuals with other ethnicity. Maori individuals were diagnosed at a mean age of 58.0 years (95% CI, 57.1-59.1 years) vs 64.3 years. (95% CI, 64.0-64.7 years) for individuals with other ethnicity, or 5 to 7 years younger, and died at mean age of 63.5 years (95% CI, 62.0-64.9 years) compared with 72.3 years (95% CI, 71.8-72.9 years) for individuals with other ethnicity, or 7 to 10 years earlier. Maori individuals presented with proportionally more advanced disease (only localized disease, 102 patients [14.5%; 95% CI, 12.0%-17.4%] vs 1413 patients [24.0%; 95% CI, 22.9%-25.1%]; P < .001) and showed an increase in regional lymph nodes (276 patients [39.1%; 95% CI, 35.5%-42.9%] vs 1796 patients [30.5%; 95% CI, 29.3%-31.8%]; P < .001) at diagnosis compared with individuals with other ethnicity. Socioeconomic status was not associated with survival. Conclusions and Relevance: This study found that Maori individuals experienced worse survival outcomes and greater mortality rates from HNC in NZ and presented with more advanced disease at a younger age. These findings suggest the need for further research to alleviate these disparities, highlight the importance of research into minority populations with HNC globally, and may encourage equity research for all cancers.


Asunto(s)
Neoplasias de Cabeza y Cuello , Humanos , Nueva Zelanda/epidemiología , Masculino , Femenino , Persona de Mediana Edad , Neoplasias de Cabeza y Cuello/mortalidad , Neoplasias de Cabeza y Cuello/etnología , Neoplasias de Cabeza y Cuello/terapia , Anciano , Estudios Retrospectivos , Etnicidad/estadística & datos numéricos , Adulto , Tasa de Supervivencia , Disparidades en el Estado de Salud , Disparidades en Atención de Salud/estadística & datos numéricos , Disparidades en Atención de Salud/etnología
2.
J Bacteriol ; 206(4): e0009524, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38564677

RESUMEN

Bacterial communities exhibit complex self-organization that contributes to their survival. To better understand the molecules that contribute to transforming a small number of cells into a heterogeneous surface biofilm community, we studied acellular aggregates, structures seen by light microscopy in Pseudomonas aeruginosa colony biofilms using light microscopy and chemical imaging. These structures differ from cellular aggregates, cohesive clusters of cells important for biofilm formation, in that they are visually distinct from cells using light microscopy and are reliant on metabolites for assembly. To investigate how these structures benefit a biofilm community we characterized three recurrent types of acellular aggregates with distinct geometries that were each abundant in specific areas of these biofilms. Alkyl quinolones (AQs) were essential for the formation of all aggregate types with AQ signatures outside the aggregates below the limit of detection. These acellular aggregates spatially sequester AQs and differentiate the biofilm space. However, the three types of aggregates showed differing properties in their size, associated cell death, and lipid content. The largest aggregate type co-localized with spatially confined cell death that was not mediated by Pf4 bacteriophage. Biofilms lacking AQs were absent of localized cell death but exhibited increased, homogeneously distributed cell death. Thus, these AQ-rich aggregates regulate metabolite accessibility, differentiate regions of the biofilm, and promote survival in biofilms.IMPORTANCEPseudomonas aeruginosa is an opportunistic pathogen with the ability to cause infection in the immune-compromised. It is well established that P. aeruginosa biofilms exhibit resilience that includes decreased susceptibility to antimicrobial treatment. This work examines the self-assembled heterogeneity in biofilm communities studying acellular aggregates, regions of condensed matter requiring alkyl quinolones (AQs). AQs are important to both virulence and biofilm formation. Aggregate structures described here spatially regulate the accessibility of these AQs, differentiate regions of the biofilm community, and despite their association with autolysis, correlate with improved P. aeruginosa colony biofilm survival.


Asunto(s)
Infecciones por Pseudomonas , Quinolonas , Humanos , Quinolonas/metabolismo , Biopelículas , Infecciones por Pseudomonas/microbiología , Virulencia , Pseudomonas aeruginosa/metabolismo
3.
ACS Appl Bio Mater ; 6(11): 4914-4921, 2023 11 20.
Artículo en Inglés | MEDLINE | ID: mdl-37878954

RESUMEN

Rhamnolipids are surfactants produced by many Pseudomonad bacteria, including the species Pseudomonas aeruginosa. These rhamnolipids are known to aid and enable numerous phenotypic traits that improve the survival of the bacteria that make them. These surfactants are also important for industrial products ranging from pharmaceuticals to cleaning supplies to cosmetics, to name a few. Rhamnolipids have structural diversity that leads to an array of congeners; however, little is known about the localization and distribution of these congeners in two-dimensional space. Differential distribution of congeners can reduce the uniformity of applications in industrial settings and create heterogeneity within biological communities. We examined the distribution patterns of combinations of rhamnolipids in commercially available mixtures, cell-free spent media, and colony biofilms using mass spectrometry. We found that even in the absence of cells, congeners exhibit different distribution patterns, leading to different rhamnolipid congener distributions on a surface. Congeners with shorter fatty acid chains were more centrally located, while longer chains were more heterogeneous and distally located. We found that congeners with similar structures can distribute differently. Within developing colony biofilms, we found rhamnolipid distribution patterns differed from cell-free environments, lacking simple trends noted in cell-free environments. Most strikingly, we found the distribution patterns of individual congeners in the colony biofilms to be diverse. We note that the congener distribution is far from homogeneous but composed of numerous local microenvironments of varied rhamnolipid congener composition.


Asunto(s)
Glucolípidos , Pseudomonas aeruginosa , Glucolípidos/química , Biopelículas , Bacterias , Tensoactivos/química
4.
PLoS Pathog ; 19(9): e1011676, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37747933

RESUMEN

Sustainable HIV remission after antiretroviral therapy (ART) withdrawal, or post-treatment control (PTC), remains a top priority for HIV treatment. We observed surprising PTC in an MHC-haplomatched cohort of MHC-M3+ SIVmac239+ Mauritian cynomolgus macaques (MCMs) initiated on ART at two weeks post-infection (wpi). None of the MCMs possessed MHC haplotypes previously associated with SIV control. For six months after ART withdrawal, we observed undetectable or transient viremia in seven of the eight MCMs, despite detecting replication competent SIV using quantitative viral outgrowth assays. In vivo depletion of CD8α+ cells induced rebound in all animals, indicating the observed PTC was mediated, at least in part, by CD8α+ cells. With intact proviral DNA assays, we found that MCMs had significantly smaller viral reservoirs two wpi than a cohort of identically infected rhesus macaques, a population that rarely develops PTC. We found a similarly small viral reservoir among six additional SIV+ MCMs in which ART was initiated at eight wpi, some of whom exhibited viral rebound. These results suggest that an unusually small viral reservoir is a hallmark among SIV+ MCMs. By evaluating immunological differences between MCMs that did and did not rebound, we identified that PTC was associated with a reduced frequency of CD4+ and CD8+ lymphocyte subsets expressing exhaustion markers. Together, these results suggest a combination of small reservoirs and immune-mediated virus suppression contribute to PTC in MCMs. Further, defining the immunologic mechanisms that engender PTC in this model may identify therapeutic targets for inducing durable HIV remission in humans.


Asunto(s)
Infecciones por VIH , Síndrome de Inmunodeficiencia Adquirida del Simio , Virus de la Inmunodeficiencia de los Simios , Humanos , Animales , Macaca mulatta , Linfocitos T CD8-positivos , Infecciones por VIH/tratamiento farmacológico , Macaca fascicularis , Carga Viral , Replicación Viral , Antirretrovirales/uso terapéutico , Antirretrovirales/farmacología
5.
bioRxiv ; 2023 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-36909458

RESUMEN

Sustainable HIV remission after antiretroviral therapy (ART) withdrawal, or post-treatment control (PTC), remains a top priority for HIV treatment. We observed surprising PTC in an MHC-haplomatched cohort of MHC-M3+ SIVmac239+ Mauritian cynomolgus macaques (MCMs) initiated on ART at two weeks post-infection (wpi). For six months after ART withdrawal, we observed undetectable or transient viremia in seven of eight MCMs. In vivo depletion of CD8α+ cells induced rebound in all animals, indicating the PTC was mediated, at least in part, by CD8α+ cells. We found that MCMs had smaller acute viral reservoirs than a cohort of identically infected rhesus macaques, a population that rarely develops PTC. The mechanisms by which unusually small viral reservoirs and CD8α+ cell-mediated virus suppression enable PTC can be investigated using this MHC-haplomatched MCM model. Further, defining the immunologic mechanisms that engender PTC in this model may identify therapeutic targets for inducing durable HIV remission in humans.

6.
J Virol ; 96(23): e0142422, 2022 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-36377872

RESUMEN

Vaccine strategies aimed at eliciting human immunodeficiency virus (HIV)-specific CD8+ T cells are one major target of interest in HIV functional cure strategies. We hypothesized that CD8+ T cells elicited by therapeutic vaccination during antiretroviral therapy (ART) would be recalled and boosted by treatment with the interleukin 15 (IL-15) superagonist N-803 after ART discontinuation. We intravenously immunized four simian immunodeficiency virus-positive (SIV+) Mauritian cynomolgus macaques receiving ART with vesicular stomatitis virus (VSV), modified vaccinia virus Ankara strain (MVA), and recombinant adenovirus serotype 5 (rAd-5) vectors all expressing SIVmac239 Gag. Immediately after ART cessation, these animals received three doses of N-803. Four control animals received no vaccines or N-803. The vaccine regimen generated a high-magnitude response involving Gag-specific CD8+ T cells that were proliferative and biased toward an effector memory phenotype. We then compared cells elicited by vaccination (Gag specific) to cells elicited by SIV infection and unaffected by vaccination (Nef specific). We found that N-803 treatment enhanced the frequencies of both bulk and proliferating antigen-specific CD8+ T cells elicited by vaccination and the antigen-specific CD8+ T cells elicited by SIV infection. In sum, we demonstrate that a therapeutic heterologous prime-boost-boost (HPBB) vaccine can elicit antigen-specific effector memory CD8+ T cells that are boosted by N-803. IMPORTANCE While antiretroviral therapy (ART) can suppress HIV replication, it is not a cure. It is therefore essential to develop therapeutic strategies to enhance the immune system to better become activated and recognize virus-infected cells. Here, we evaluated a novel therapeutic vaccination strategy delivered to SIV+ Mauritian cynomolgus macaques receiving ART. ART was then discontinued and we delivered an immunotherapeutic agent (N-803) after ART withdrawal with the goal of eliciting and boosting anti-SIV cellular immunity. Immunologic and virologic analysis of peripheral blood and lymph nodes collected from these animals revealed transient boosts in the frequency, activation, proliferation, and memory phenotype of CD4+ and CD8+ T cells following each intervention. Overall, these results are important in educating the field of the transient nature of the immunological responses to this particular therapeutic regimen and the similar effects of N-803 on boosting T cells elicited by vaccination or elicited naturally by infection.


Asunto(s)
Linfocitos T CD8-positivos , Vacunas contra el SIDAS , Síndrome de Inmunodeficiencia Adquirida del Simio , Virus de la Inmunodeficiencia de los Simios , Animales , Proliferación Celular , Macaca mulatta/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Vacunación , Virus Vaccinia
7.
J Chem Phys ; 154(20): 204201, 2021 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-34241187

RESUMEN

Pseudomonas aeruginosa is an opportunistic human pathogen implicated in both acute and chronic diseases, which resists antibiotic treatment, in part by forming physical and chemical barriers such as biofilms. Here, we explore the use of confocal Raman imaging to characterize the three-dimensional (3D) spatial distribution of alkyl quinolones (AQs) in P. aeruginosa biofilms by reconstructing depth profiles from hyperspectral Raman data. AQs are important to quorum sensing (QS), virulence, and other actions of P. aeruginosa. Three-dimensional distributions of three different AQs (PQS, HQNO, and HHQ) were observed to have a significant depth, suggesting 3D anisotropic shapes-sheet-like rectangular solids for HQNO and extended cylinders for PQS. Similar to observations from 2D imaging studies, spectral features characteristic of AQs (HQNO or PQS) and the amide I vibration from peptide-containing species were found to correlate with the PQS cylinders typically located at the tips of the HQNO rectangular solids. In the QS-deficient mutant lasIrhlI, a small globular component was observed, whose highly localized nature and similarity in size to a P. aeruginosa cell suggest that the feature arises from HHQ localized in the vicinity of the cell from which it was secreted. The difference in the shapes and sizes of the aggregates of the three AQs in wild-type and mutant P. aeruginosa is likely related to the difference in the cellular response to growth conditions, environmental stress, metabolic levels, or other structural and biochemical variations inside biofilms. This study provides a new route to characterizing the 3D structure of biofilms and shows the potential of confocal Raman imaging to elucidate the nature of heterogeneous biofilms in all three spatial dimensions. These capabilities should be applicable as a tool in studies of infectious diseases.


Asunto(s)
Biopelículas/efectos de los fármacos , Pseudomonas aeruginosa/efectos de los fármacos , Quinolonas/farmacología , Biopelículas/crecimiento & desarrollo , Microscopía Confocal , Quinolonas/química , Espectrometría Raman
8.
Appl Environ Microbiol ; 87(8)2021 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-33579687

RESUMEN

There are many hydrated surface niches that are neither static nor continuously flowing that are colonized by microbes such as bacteria. Such periodic hydrodynamic regimes are distinct from aquatic systems where microbial dissemination is reasonably predicted by assuming continuous flow or static systems where motile microbes largely control their own fate. Here we show how non-motile bacteria exhibit rapid, dispersive bursts of movement over surfaces using transient confluent hydration from the environment, which we term "surface hydrodispersion" where cells traverse thousands of cell lengths within minutes. The fraction of the population disseminated by surface hydrodispersion is small-on order of 1 cell per million. Thus, surface hydrodispersion can promote isolated distribution of single cells, which is unlike other characterized active and passive surface motilities. We describe this translocation using a continuous time random walk modeling approach and find in computational simulations that transient fluid accumulation, dilution, and gravitational pull are the contributing factors. Surface hydrodispersion, consistent with advection, is unlike simple colony expansion as it dramatically alters spatial relationships, shown here with Staphylococcus aureus, which becomes increasingly virulent when isolated from Corynebacterium striatum Surface hydrodispersion of non-motile bacteria exploiting transient fluid availability and gravity is a mechanism that can result in sporadic and sudden shifts in microbial community behavior. To better understand how this movement can impact biogeography on the millimeter scale, this work describes a system for study of primary factors behind this movement as well as a stochastic model describing this dispersal.Importance: Understanding the dynamics within microbiome communities is a challenge. Knowledge of phylogeny and spatial arrangement has led to increased understanding of numerous polymicrobial communities yet, these snapshots do not convey the dynamics of populations over time. The actual biogeography of any microbiome controls the potential interactions, governing any possible antagonistic or synergistic behavior. Accordingly, a shift in biogeography can enable new behavior. Little is known about the movement mechanisms of "non-motile" microbes. Here we characterize a universal means of movement we term hydrodispersion where non-motile bacteria are transported thousands of cell lengths in minutes. We show that only a small fraction of the population is translocated by hydrodispersion and describe this movement further using a random-walk mathematical model approach in silico We demonstrate the importance of hydrodispersion by showing that Staphylococcus aureus can separate from a coculture inoculation with Corynebacterium striatum thus permitting transition to a more virulent state.

9.
Obes Surg ; 31(1): 111-116, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32734567

RESUMEN

BACKGROUND: Laparoscopic sleeve gastrectomy (LSG) is the most common bariatric surgical procedure worldwide. Educational videos of LSGs are available from online sources with YouTube® being the most popular online video repository. However, due to the unrestricted and uncontrolled nature of YouTube®, anyone can upload videos without peer review or standardization. The LAP-VEGaS guidelines were formed to guide the production of high-quality surgical videos. The aim of this study is to use the LAP-VEGaS guidelines to determine if videos of LSGs available on Youtube® are of an acceptable standard for surgical educational purposes. METHODS: A YouTube® search was performed using the term laparoscopic sleeve gastrectomy. Appropriate videos were analysed by two individuals using the sixteen LAP-VEGaS guidelines. RESULTS: A total of 575 videos were found, of which 202 videos were included and analysed using the LAP-VEGaS guidelines. The median video guideline score was 6/16 with 89% of videos meeting less than half of all guidelines. There was no correlation between the LAP-VEGaS score and view count. CONCLUSIONS: There is an abundance of laparoscopic sleeve gastrectomy educational videos available on YouTube®; however, when analysed using the LAP-VEGaS guidelines, the majority do not meet acceptable educational standards for surgical training purposes.


Asunto(s)
Laparoscopía , Obesidad Mórbida , Medios de Comunicación Sociales , Gastrectomía , Humanos , Obesidad Mórbida/cirugía , Grabación en Video
10.
J Chem Educ ; 97(3): 786-792, 2020 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-32174646

RESUMEN

A two to three period analytical chemistry experiment has been developed which allows second year students to explore chemical color tests used to detect adulterated pharmaceuticals. Students prepare several paper analytical devices (PADs) to generate positive and negative controls antibiotics, along with cutting agents such as starch and chalk. These PADs are used to identify the active ingredients and excipients in mystery tablets prepared by their classmates. In the second part of the lab, the students select an individual color test and design an experiment to quantify their mystery pill's active pharmaceutical ingredient (API). Nearly all of the student groups were able to successfully identify adulterants present in their mystery tablets. The quantification of the mystery tablets was also successful with all but one group calculating the correct concentration within 6%. In a postlab assessment, the students identified their largest gains in their ability to analyze data and other information, skill in science writing, and learning of laboratory techniques.

11.
J Med Microbiol ; 68(10): 1507-1516, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31460858

RESUMEN

Introduction. Prosthetic joint infections (PJIs) are challenging to treat therapeutically because the infectious agents often are resistant to antibiotics and capable of abundant growth in surface-attached biofilms. Though infection rates are low, ca. 1-2 %, the overall increase in the sheer number of joint replacement surgeries results in an increase in patients at risk.Aims. This study investigates the consensus of microbial species comprising PJI ecology, which is currently lacking.Methodology. In this study, PJI populations from seven patients were analysed using combined culturing and whole-genome shotgun sequencing (WGSS) to establish population profiles and compare WGSS and culture methods for detection and identification of the PJI microbiome.Results. WGSS detected strains when culture did not, notably dormant, culture-resistant and rare microbes. The CosmosID algorithm was used to predict micro-organisms present in the PJI and discriminate contaminants. However, culturing indicated the presence of microbes falling below the WGSS algorithm threshold. In these instances, microbes cultured are believed to be minor species. The two strategies were combined to build a population profile.Conclusions. Variability between and among PJIs showed that most infections were distinct and unique. Comparative analysis of populations revealed PJIs to form clusters that were related to, but separate from, vaginal, skin and gut microbiomes. Fungi and protists were detected by WGSS, but the role of fungi is just beginning to be understood and for protists it is unknown. These micro-organisms and their novel and strain-specific microbial interactions remain to be determined in current clinical tests.


Asunto(s)
Bacterias/genética , Bacterias/aislamiento & purificación , Hongos/aislamiento & purificación , Artropatías/microbiología , Microbiota , Infecciones Relacionadas con Prótesis/microbiología , Bacterias/clasificación , Femenino , Hongos/clasificación , Hongos/genética , Humanos , Articulaciones/microbiología , Articulaciones/cirugía , Masculino , Prótesis e Implantes/efectos adversos , Prótesis e Implantes/microbiología , Infecciones Relacionadas con Prótesis/etiología , Estudios Retrospectivos , Secuenciación Completa del Genoma
12.
J Bacteriol ; 200(11): e00014-18, 2018 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-29555698

RESUMEN

The degree to which surface motile bacteria explore their surroundings is influenced by aspects of their local environment. Accordingly, regulation of surface motility is controlled by numerous chemical, physical, and biological stimuli. Discernment of such regulation due to these multiple cues is a formidable challenge. Additionally inherent ambiguity and variability from the assays used to assess surface motility can be an obstacle to clear delineation of regulated surface motility behavior. Numerous studies have reported single environmental determinants of microbial motility and lifestyle behavior but the translation of these data to understand surface motility and bacterial colonization of human host or environmental surfaces is unclear. Here, we describe the current state of the field and our understanding of exogenous factors that influence bacterial surface motility.

14.
Am J Trop Med Hyg ; 92(6 Suppl): 17-23, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25897064

RESUMEN

Carrying out chemical analysis of antimalarials to detect low-quality medications before they reach a patient is a costly venture. Here, we show that a library of chemical color tests embedded on a paper card can presumptively identify formulations corresponding to very low quality antimalarial drugs. The presence or absence of chloroquine (CQ), doxycycline (DOX), quinine, sulfadoxine, pyrimethamine, and primaquine antimalarial medications, in addition to fillers used in low-quality pharmaceuticals, are indicated by patterns of colors that are generated on the test cards. Test card sensitivity for detection of these pure components ranges from 90% to 100% with no false positives in the absence of pharmaceutical. The color intensities from reactions characteristic of CQ or DOX allowed visual detection of formulations of these medications cut with 60% or 100% filler, although samples cut with 30% filler could not be reliably detected colorimetrically. However, the addition of unexpected fillers, even in 30% quantities, or substitute pharmaceuticals, could sometimes be detected by other color reactions on the test cards. Tests are simple and inexpensive enough to be carried out in clinics, pharmacies, and ports of entry and could provide a screening method to presumptively indicate very low quality medicines throughout the supply chain.


Asunto(s)
Antimaláricos/química , Antimaláricos/normas , Papel , Tiras Reactivas/química , Colorimetría/instrumentación , Colorimetría/métodos , Medicamentos Falsificados/química , Países en Desarrollo , Reacciones Falso Positivas , Control de Calidad , Tiras Reactivas/economía , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
15.
Anal Bioanal Chem ; 407(2): 615-9, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25381614

RESUMEN

Paper-based devices serve to address many analytical questions both inside and outside of the laboratory setting. For the first time, yeast is used to construct a whole-cell, paper-based biosensor device. This biologically based paper analytical device (BioPAD) is sensitive to antibiotics in the tetracycline family, and it could potentially address questions of pharmaceutical quality as well as antibiotic contamination in liquids. Our BioPAD can qualitatively discriminate the presence/absence of doxycycline over a range of 30-10,000 µg/mL. In an analysis of a doxycycline dosage form (tablet) commonly used for malaria prophylaxis, BioPADs identified the presence of antibiotic with 92 and 95 % sensitivity, evaluated by eye and computer-assisted image analysis, respectively, with no false positives by either method. BioPADs were found to remain viable for at least 415 days when stored at 4 °C. This research demonstrates the utility of whole yeast cells in paper-based pharmaceutical testing, and it highlights the potential for the development of yeast-based BioPADs to address a range of qualitative analytical questions, especially in low resource settings.


Asunto(s)
Técnicas Biosensibles/instrumentación , Técnicas Biosensibles/métodos , Química Farmacéutica/métodos , Papel , Saccharomyces cerevisiae , Células Inmovilizadas , Química Farmacéutica/instrumentación , Doxiciclina/análisis , Diseño de Equipo , Reacciones Falso Positivas , Procesamiento de Imagen Asistido por Computador/métodos , Límite de Detección , Saccharomyces cerevisiae/efectos de los fármacos , Saccharomyces cerevisiae/crecimiento & desarrollo
16.
Anal Chem ; 85(13): 6453-60, 2013 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-23725012

RESUMEN

Reports of low-quality pharmaceuticals have been on the rise in the past decade, with the greatest prevalence of substandard medicines in developing countries, where lapses in manufacturing quality control or breaches in the supply chain allow substandard medicines to reach the marketplace. Here, we describe inexpensive test cards for fast field screening of pharmaceutical dosage forms containing beta lactam antibiotics or combinations of the four first-line antituberculosis (TB) drugs. The devices detect the active pharmaceutical ingredients (APIs) ampicillin, amoxicillin, rifampicin, isoniazid, ethambutol, and pyrazinamide and also screen for substitute pharmaceuticals, such as acetaminophen and chloroquine that may be found in counterfeit pharmaceuticals. The tests can detect binders and fillers such as chalk, talc, and starch not revealed by traditional chromatographic methods. These paper devices contain 12 lanes, separated by hydrophobic barriers, with different reagents deposited in the lanes. The user rubs some of the solid pharmaceutical across the lanes and dips the edge of the paper into water. As water climbs up the lanes by capillary action, it triggers a library of different chemical tests and a timer to indicate when the tests are completed. The reactions in each lane generate colors to form a "color bar code" which can be analyzed visually by comparison with standard outcomes. Although quantification of the APIs is poor compared with conventional analytical methods, the sensitivity and selectivity for the analytes is high enough to pick out suspicious formulations containing no API or a substitute API as well as formulations containing APIs that have been "cut" with inactive ingredients.


Asunto(s)
Antituberculosos/análisis , Química Farmacéutica/métodos , Cromatografía en Papel/métodos , beta-Lactamas/análisis , Antituberculosos/normas , Química Farmacéutica/normas , Cromatografía en Papel/normas , Países en Desarrollo , Evaluación Preclínica de Medicamentos/métodos , Evaluación Preclínica de Medicamentos/normas , Control de Calidad , Reproducibilidad de los Resultados , beta-Lactamas/normas
17.
PLoS Negl Trop Dis ; 5(2): e1005, 2011 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-21347443

RESUMEN

The World Health Organization has called for an effort to eliminate Lymphatic Filariasis (LF) around the world. In regions where the disease is endemic, local production and distribution of medicated salt dosed with diethylcarbamazine (DEC) has been an effective method for eradicating LF. A partner of the Notre Dame Haiti program, Group SPES in Port-au-Prince, Haiti, produces a medicated salt called Bon Sel. Coarse salt is pre-washed and sprayed with a solution of DEC citrate and potassium iodate. Iodine levels are routinely monitored on site by a titrimetric method. However, the factory had no method for monitoring DEC. Critical analytical issues include 1) determining whether the amount of DEC in each lot of Bon Sel is within safe and therapeutically useful limits, 2) monitoring variability within and between production runs, and 3) determining the effect of a common local practice (washing salt before use) on the availability of DEC. This paper describes a novel titrimetric method for analysis of DEC citrate in medicated salt. The analysis needs no electrical power and requires only a balance, volumetric glassware, and burets that most salt production programs have on hand for monitoring iodine levels. The staff of the factory used this analysis method on site to detect underloading of DEC on the salt by their sprayer and to test a process change that fixed the problem.


Asunto(s)
Técnicas de Química Analítica , Dietilcarbamazina/análisis , Filaricidas/análisis , Yodo/química , Haití , Humanos , Cloruro de Sodio Dietético
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