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1.
Opt Express ; 30(25): 45824-45831, 2022 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-36522978

RESUMEN

There are limited fiber-based single-mode laser sources over the visible and near infrared range. Nonlinear conversion through four-wave mixing in photonic crystal fibers allows for the generation of new wavelengths far from a pump wavelength. Utilizing an all-fiber spliced configuration, we convert 1064 nm light into a W-level signal in the 750 nm - 820 nm spectral region. We demonstrate over 7.9 watts in the signal band, out of a custom photonic crystal fiber with M2 < 1.15. The input peak power as well as fiber length can be selected to keep the converted power in a 0.6 nm narrow emission band or broaden the output to 45 nm spectral band with spectral density greater than 50 mW/nm by pumping with higher peak powers.

2.
Malar J ; 21(1): 259, 2022 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-36071520

RESUMEN

BACKGROUND: Anti-malarial resistance remains an important public health challenge in Cambodia. The effectiveness of three therapies for uncomplicated falciparum malaria was evaluated in Oddar Meanchey province in Northern Cambodia from 2009 to 2011. METHODS: In this randomized, open-label, parallel group-controlled trial, 211 subjects at least 5 years old with uncomplicated falciparum malaria were treated with 3 days of directly observed therapy: 63 received artesunate-mefloquine (AS/MQ), 77 received dihydroartemisinin-piperaquine (DHA/PPQ), and 71 received atovaquone-proguanil (ATQ/PG). The subjects were followed for 42 days or until recurrent parasitaemia. Genotyping of msp1, msp2, and glurp among individual parasite isolates distinguished recrudescence from reinfection. Pfmdr1 copy number was measured by real-time PCR and half-maximal parasite inhibitory concentrations (IC50) were measured in vitro by 48-h isotopic hypoxanthine incorporation assay. RESULTS: The per-protocol PCR-adjusted efficacy (95% confidence interval) at 42 days was 80.6% (70.8-90.5%) for AS/MQ, 97.2% (93.3-100%) for DHA/PPQ, and 92.9% (86.1-99.6%) for ATQ/PG. On day 3, 57.9% remained parasitaemic in the AS/MQ and DHA/PPQ arms. At baseline, 46.9% had microscopic Plasmodium falciparum gametocytaemia. Both recurrences in the DHA/PPQ arm lost Pfmdr1 copy number amplification at recrudescence. All four recurrences in the ATQ/PG arm were wild-type for cytochrome bc1. One subject withdrew from the ATQ/PG arm due to drug allergy. CONCLUSIONS: This study was conducted at the epicentre of substantial multi-drug resistance that emerged soon thereafter. Occurring early in the national transition from AS/MQ to DHA/PPQ, both DHA/PPQ and ATQ/PG had acceptable efficacy against uncomplicated falciparum malaria. However, efficacy of AS/MQ was only 80% with apparent mefloquine resistance based on elevated Pfmdr1 copy number and IC50. By 2009, there was already significant evidence of artemisinin resistance not previously reported at the Northern Cambodia-Thai border. This study suggests the basis for early development of significant DHA/PPQ failures within 3 years of introduction. Artemisinin resistance likely occurred on the Northern border concurrently with that reported along the Western border in Pailin. Trial registration This legacy trial was conducted prior to International Committee of Medical Journal Editors' requirements for preregistration on ClinicalTrials.gov. The full protocol has been provided.


Asunto(s)
Antimaláricos , Artemisininas , Malaria Falciparum , Antimaláricos/farmacología , Antimaláricos/uso terapéutico , Artemisininas/farmacología , Artemisininas/uso terapéutico , Artesunato/uso terapéutico , Cambodia , Preescolar , Humanos , Malaria Falciparum/tratamiento farmacológico , Malaria Falciparum/parasitología , Mefloquina/farmacología , Mefloquina/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto , Recurrencia
3.
J Pharmacol Exp Ther ; 379(2): 175-181, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34433578

RESUMEN

Cefazolin is a first-line antibiotic to treat infection related to deployment-associated blast injuries. Prior literature demonstrated a 331% increase cefazolin liver area under the curve (AUC) in mice exposed to a survivable blast compared with controls. We repeated the experiment, validated the findings, and established a semimechanistic two-compartment pharmacokinetic (PK) model with effect compartments representing the liver and skin. We found that blast statistically significantly increased the pseudo-partition coefficient to the liver by 326% (95% confidence interval: 76-737%), which corresponds to the observed 331% increase in cefazolin liver AUC described previously. To a lesser extent, plasma AUC in blasted mice increased 14-45% compared with controls. Nevertheless, the effects of blast on cefazolin PK were transient, normalizing by 10 hours after the dose. It is unclear as to how this blast effect t emporally translates to humans; however, given the short-lived effect on PK, there is insufficient evidence to recommend cefazolin dosing changes based on blast overpressure injury alone. Clinicians should be aware that cefazolin may cause drug-induced liver injury with a single dose and the risk may be higher in patients with blast overpressure injury based on our findings. SIGNIFICANCE STATEMENT: Blast exposure significantly, but transiently, alters cefazolin pharmacokinetics in mice. The questions of whether other medications or potential long-term consequences in humans need further exploration.


Asunto(s)
Antibacterianos/farmacocinética , Traumatismos por Explosión/metabolismo , Cefazolina/farmacocinética , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Modelos Biológicos , Animales , Antibacterianos/toxicidad , Traumatismos por Explosión/complicaciones , Traumatismos por Explosión/patología , Cefazolina/toxicidad , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Masculino , Ratones , Ratones Endogámicos BALB C , Presión
4.
Front Endocrinol (Lausanne) ; 15: 1444568, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39149118

RESUMEN

The Food and Drug Administration's (FDA) obesity drug guidance is set on the basis of body mass index (BMI), with thresholds of either BMI ≥30 or BMI ≥27 kg/m2 with weight-related comorbidities. While BMI is associated with obesity-related health outcomes, there are known limitations to use as a direct measure of body fat or metabolic health, and the American Medical Association has highlighted limitations of BMI in assessing individual obesity risks. BMI thresholds impose a barrier to treatment. In a sample from the NHANES dataset (n=6,646 men and women), 36% of individuals with metabolic syndrome (MetS) may not be eligible for obesity pharmacotherapy. This analysis provides quantifiable justification for refinement of the BMI treatment criteria with a more holistic assessment of individual obesity-related disease risk.


Asunto(s)
Índice de Masa Corporal , Síndrome Metabólico , Obesidad , Humanos , Masculino , Femenino , Encuestas Nutricionales , Adulto , Persona de Mediana Edad
5.
Artículo en Inglés | MEDLINE | ID: mdl-38747476

RESUMEN

OBJECTIVE: Thresholds for overweight and obesity are currently defined by body mass index (BMI), a poor surrogate marker of actual adiposity (percent body fat, %BF). Practical modern technologies provide estimates of %BF but medical providers need outcome-based %BF thresholds to guide patients. This analysis determines %BF thresholds based on key obesity-related comorbidities, exhibited as metabolic syndrome (MetSyn). These limits were compared to existing BMI thresholds of overweight and obesity. DESIGN: Correlational analysis of data from cross sectional sampling of 16,918 adults (8,734 men and 8,184 women) from the US population, accessed by the National Health and Nutrition Examination Survey (NHANES) public use datasets. RESULTS: Individuals measured by BMI as overweight (BMI>25 kg/m2) and with obesity (BMI>30 kg/m2) included 5% and 35% of individuals with MetSyn, respectively. For men, there were no cases of MetSyn below 18%BF, %BF equivalence to "overweight" (i.e., 5% of MetSyn individuals) occurred at 25%BF, and "obesity" (i.e., 35% of MetSyn individuals) corresponded to 30%BF. For women, there were no cases of MetSyn below 30%BF, "overweight" occurred at 36%BF, and "obesity" corresponded to 42%BF. Comparison of BMI to %BF illustrates the wide range of variability in BMI prediction of %BF, highlighting the potential importance of using more direct measures of adiposity to manage obesity-related disease. CONCLUSIONS: Practical methods of body composition estimation can now replace the indirect BMI assessment for obesity management, using threshold values provided from this study. Clinically relevant "overweight" can be defined as 25 and 36% BF for men and women, respectively, and "obesity" is defined as 30 and 42% BF for men and women.

6.
Mil Med ; 187(Suppl 1): 1-8, 2021 12 30.
Artículo en Inglés | MEDLINE | ID: mdl-34967404

RESUMEN

Pharmacogenomics (PGx) plays a fundamental role in personalized medicine, providing an evidence-based treatment approach centered on the relationship between genomic variations and their effect on drug metabolism. Cytochrome P450 (CYP450) enzymes are responsible for the metabolism of most clinically prescribed drugs and a major source of variability in drug pharmacokinetics and pharmacodynamics. To assess the prevalence of PGx testing within the Military Health System (MHS), testing of specific CYP450 enzymes was evaluated. Data were retrospectively obtained from the Military Health System Management Analysis and Reporting Tool (M2) database. Patient demographics were identified for each test, along with TRICARE status, military treatment facility, clinic, and National Provider Identifier. A total of 929 patients received 1,833 PGx tests, predominantly composed of active duty/guard service members (N = 460; 49.5%), with highest testing rates in the army (51.5%). An even distribution in testing was observed among gender, with the highest rates in Caucasians (41.7%). Of the CYP enzymes assessed, CYP2C19 and CYP2D6 accounted for 87.8% of all PGx CYP testing. The majority of patients were tested in psychiatry clinics (N = 496; 53.4%) and primary care clinics (N = 233; 25.1%), accounting for 56.4% and 24.8% of all tests, respectively. Testing was found to be provider driven, suggesting a lack of a standardized approach to PGx and its application in patient care within the MHS. We initially recommend targeted education and revising testing labels to be more uniform and informative. Long-term recommendations include establishing pharmacy-driven protocols and point-of-care PGx testing to optimize patient outcomes.


Asunto(s)
Servicios de Salud Militares , Farmacogenética , Citocromo P-450 CYP2D6/genética , Sistema Enzimático del Citocromo P-450/genética , Humanos , Estudios Retrospectivos
7.
Mil Med ; 187(Suppl 1): 9-17, 2021 12 30.
Artículo en Inglés | MEDLINE | ID: mdl-34967405

RESUMEN

INTRODUCTION: Clinical utilization of pharmacogenomics (PGx) testing is highly institutionally dependent, and little information is known about provider practices of PGx testing in the Military Health System (MHS). In this study, we aimed to characterize Clinical Pharmacogenetics Implementation Consortium (CPIC) actionable prescription (Rx) patterns and their temporal relationship with PGx testing in the MHS. METHODS: Using data from the Military Health System Management Analysis and Reporting Tool (M2) database, this retrospective cohort study included all patients receiving at least one PGx test and at least one CPIC actionable Rx from January 2015 to August 2020 (845 patients, 1,471 PGx, 7,725 index CPIC actionable Rxs). Rx patterns and temporal relationships with PGx testing were characterized via descriptive statistics. Binomial regression was used to determine which patient and provider characteristics were associated with a patient receiving a PGx test within 30 days of an index Rx. RESULTS: Patients had a median of 9 index CPIC actionable Rx's (range 1-26). Pain medications were most commonly prescribed (N = 794, 94% patients with at least 1 Rx). However, pain medication had the lowest Rx-PGx match rate (40%) compared to an average of 62% Rx-PGx match rate for all CPIC drugs. Antidepressants were also commonly prescribed (N = 668, 79.1% patients with at least 1 Rx), and antidepressants had the highest Rx-PGx match rate of 86.7%. A minority of providers (20%, N = 249) ordered the majority of PGx tests (86.1%, N = 1,266) and only 8.3% of PGx tests (N = 398) matched to a CPIC actionable drug within 30 days of the test (defined by Rxs ordered within 30 days before or after the PGx test). However, approximately 39.8% of patients (N = 317) had at least one drug match to a PGx test within 30 days. The largest predictor of whether a patient received a PGx test within 30 days of any index Rx was whether or not a specific psychiatry provider ordered the PGx test (odds ratio; OR 3.7, 95% CI 2.13-6.54, P < 0.001). Neither the CPIC level of evidence nor FDA PGx actionable or informative labels had a significant effect on PGx test timing. CONCLUSIONS: PGx testing was generally limited to high Rx-drug users and was found to be an under-utilized resource. PGx testing did not typically follow CPIC guidelines. Implementing PGx testing protocols, simplifying PGx test-ordering by incorporating at minimum CYP2D6, CYP2C19, and CYP2C9 into PGx-testing panels, and unifying providers' PGx knowledgebase in the MHS are feasible and would improve the clinical utilization of PGx tests in the MHS.


Asunto(s)
Servicios de Salud Militares , Farmacogenética , Citocromo P-450 CYP2D6 , Prescripciones de Medicamentos , Humanos , Estudios Retrospectivos
9.
Med Decis Making ; 28(5): 713-22, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18378939

RESUMEN

OBJECTIVE: To analyze the relative influence of factors in decisions for public insurance coverage of new drugs in Australia. DATA SOURCES: Evidence presented at meetings of the Australian Pharmaceutical Benefits Advisory Committee (PBAC) that makes recommendations on coverage of drugs under Pharmaceutical Benefits Scheme. STUDY SELECTION: All major submissions to the PBAC between February 1994 and December 2004 (n = 858) if one of the outcomes measured was life year gained (n=138) or quality-adjusted life years (QALYs) gained (n=116). RESULTS: Clinical significance, cost-effectiveness, cost to government, and severity of disease were significant influences on decisions. Compared to the average submission, clinical significance increased the probability of recommending coverage by 0.21 (95% confidence interval [CI] 0.02 to 0.40), whereas a drug in a life-threatening condition had an increased probability of being recommended for coverage of 0.38 (0.06 to 0.69). An increase in $A10,000 from a mean incremental cost per QALY of $A46,400 reduced the probability of listing by 0.06 (95% CI 0.04 to 0.1). CONCLUSIONS: The PBAC provides an example of the long-term stability and coherence of evidence-based coverage and pricing decisions for drugs that weighs up the evidence on clinical effectiveness, clinical need, and value for money. There is no evidence of a fixed public threshold value of life years or QALYs, but willingness to pay is clearly related to the characteristics of the clinical condition, perceived confidence in the evidence of effectiveness and its relevance, as well as total cost to government.


Asunto(s)
Cobertura del Seguro/economía , Preparaciones Farmacéuticas/economía , Australia , Toma de Decisiones , Seguro de Servicios Farmacéuticos , Modelos Estadísticos , Programas Nacionales de Salud , Años de Vida Ajustados por Calidad de Vida , Estudios Retrospectivos
11.
Opt Express ; 14(24): 11687-93, 2006 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-19529589

RESUMEN

A modified Barium Gallo-Germanate glass has been developed as an exit window for high energy lasers operating in the mid-infrared wavelength region. All the physical properties, for application as a window for high energy laser systems have been measured. Absorption loss and thermo-optic coefficient were identified as key in developing the Barium Gallo-Germanate glass for high energy laser applications. A purification method was developed to reduce the absorption loss of the glass from 6x10(-2) cm(-1) to 2x10(-3) cm(-1) at 3.8 mum. Manufacturability in large size windows has been demonstrated with the fabrication of an 18" diameter prototype window. Modified Barium Gallo-Germanate glasses have also been developed with lower thermo-optic coefficient resulting in lower optical path distortion.

12.
Artículo en Inglés | MEDLINE | ID: mdl-25938794

RESUMEN

BACKGROUND: Orphan medicines used to treat patients with rare diseases often come at high costs with lower levels of clinical evidence. We compared the likelihood and timeliness of reimbursement for orphan medicines with non-orphan medicines in Australia between 2005 and 2012. METHODS: We developed two key assessment metrics to compare submissions and outcomes for new orphan medicines with those for new non-orphan medicines, viz., the likelihood of submissions being recommended by the Pharmaceutical Benefits Advisory Committee (PBAC) (success rate) and the time from Therapeutic Goods Administration registration to reimbursement (overall timeliness). RESULTS: Thirty eight out of 95 outcomes for orphan medicines (40%) received a PBAC recommendation compared to 257/481 (53%) for non-orphan medicines (p = 0.17). The PBAC recommendations that resulted in listings were comparable between the orphan and non-orphan categories (33/38 [87%] vs 218/257 [85%], respectively, p = 0.74). CONCLUSION: The results suggested orphan medicines were not accorded any special status for reimbursement.


Asunto(s)
Accesibilidad a los Servicios de Salud/economía , Seguro de Servicios Farmacéuticos/economía , Producción de Medicamentos sin Interés Comercial/economía , Enfermedades Raras/economía , Australia , Humanos , Enfermedades Raras/tratamiento farmacológico , Mecanismo de Reembolso/economía , Factores de Tiempo
13.
Appl Opt ; 46(32): 7889-91, 2007 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-17994140

RESUMEN

Barium gallogermanate (BGG) glasses are currently being explored as a viable low cost material for numerous U.S. defense and commercial visible-infrared window applications. These glasses are transparent from 0.4 mum to beyond 5.0 mum and can be easily made in large optics and complex shapes with high index homogeneity. For high-energy laser (HEL) applications, knowledge of the thermo-optic coefficient (dn/dT) of the window material is important in determining the optical path distortion. The dn/dT measurements were made on BGG glass at 633 and 3390 nm and compared with the values for multispectral ZnS. The dn/dT for BGG glass was approximately 1/5 the value for multispectral ZnS, giving BGG glass a clear advantage for HEL applications.

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