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1.
PLoS One ; 18(10): e0290702, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37812611

RESUMEN

INTRODUCTION: Interleukin 6 (IL-6) activates cells through its unique heterodimeric signaling complex of IL-6 receptor (IL6R) subunit and interleukin 6 signal transducer ß-subunit glycoprotein 130 (gp130). The objective of this study was to investigate associations among serum levels of IL-6, sIL-6R, sgp130 and relative fluorescence intensity (RFI) of the α-subunit of the IL-6 receptor (CD126) on T-cells of HIV-1 infected and uninfected men. METHODS: Blood samples were obtained from 69 HIV-1-infected men on Highly Active Antiretroviral Therapy (HAART) with mean age of 49.1 and 52 HIV-1-uninfected with mean age of 54.3 years -. All men were participating in the Los Angeles Multi-Center AIDS Cohort Study (MACS). Serum levels of IL-6, sIL-6R, sgp130 were measured by enzyme-linked immunoassays and T-cell phenotypic analysis and RFI of CD126 on CD4+ and CD8+ by flow cytometry. RESULTS: Mean serum levels of IL-6, sIL6R, sgp130 and of CD126 RFI on CD4+ were 4.34 pg/mL, 39.3 ng/mL, 349 ng/mL and 526 RFI respectively for HIV-1-infected men and 2.74 pg/mL, 41.9 ng/mL, 318 ng/mL and 561 RFI respectively for HIV-1-uninfected men. The mean serum concentrations of IL-6, sIL-6R in HIV-1-infected and uninfected men were not significantly different (p>0.05). There was a positive correlation between plasma HIV-1 RNA and the levels of IL-6 (p<0.001), sIL6R (p = 0.002) but no correlation with sgp130 (p = 0.339). In addition, there was a negative correlation between serum levels of IL-6 with RFI of CD126 on CD4+ (p = 0.037) and a positive correlation between serum levels of sgp130 (p = 0.021) and sIL-6R in HIV-1-infected men. CONCLUSION: Knowledge of biological variation, differences in the blood levels of biomarkers among healthy individuals and individuals experiencing illness, are very important for selection of appropriate tests for stage and progression of disease. Our data suggest no correlation among IL-6, and sIL-R6, in the treated phase of HIV-1 infection. The action and blood level of IL-6 and its receptors may be different at each stage of a disease progression.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida , VIH-1 , Masculino , Humanos , Persona de Mediana Edad , Receptor gp130 de Citocinas , Interleucina-6 , Estudios de Cohortes , Los Angeles , Linfocitos T , Receptores de Interleucina-6 , Glicoproteínas
3.
PLoS One ; 17(12): e0278749, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36542608

RESUMEN

The Democratic Republic of the Congo (DRC) has a high measles incidence despite elimination efforts and has yet to introduce rubella vaccine. We evaluated the performance of a prototype rapid digital microfluidics powered (DMF) enzyme-linked immunoassay (ELISA) assessing measles and rubella infection, by testing for immunoglobulin M (IgM), and immunity from natural infection or vaccine, by testing immunoglobulin G (IgG), in outbreak settings. Field evaluations were conducted during September 2017, in Kinshasa province, DRC. Blood specimens were collected during an outbreak investigation of suspected measles cases and tested for measles and rubella IgM and IgG using the DMF-ELISA in the field. Simultaneously, a household serosurvey for measles and rubella IgG was conducted in a recently confirmed measles outbreak area. DMF-ELISA results were compared with reference ELISA results tested at DRC's National Public Health Laboratory and the US Centers for Disease Control and Prevention. Of 157 suspected measles cases, rubella IgM was detected in 54% while measles IgM was detected in 13%. Measles IgG-positive cases were higher among vaccinated persons (87%) than unvaccinated persons (72%). In the recent measles outbreak area, measles IgG seroprevalence was 93% overall, while rubella seroprevalence was lower for children (77%) than women (98%). Compared with reference ELISA, DMF-ELISA sensitivity and specificity were 82% and 78% for measles IgG; 88% and 89% for measles IgM; 85% and 85% for rubella IgG; and 81% and 83% for rubella IgM, respectively. Rubella infection was detected in more than half of persons meeting the suspected measles case definition during a presumed measles outbreak, suggesting substantial unrecognized rubella incidence, and highlighting the need for rubella vaccine introduction into the national schedule. The performance of the DMF-ELISA suggested that this technology can be used to develop rapid diagnostic tests for measles and rubella.


Asunto(s)
Sarampión , Rubéola (Sarampión Alemán) , Niño , Humanos , Femenino , República Democrática del Congo/epidemiología , Estudios Seroepidemiológicos , Microfluídica , Anticuerpos Antivirales , Rubéola (Sarampión Alemán)/diagnóstico , Rubéola (Sarampión Alemán)/epidemiología , Rubéola (Sarampión Alemán)/prevención & control , Sarampión/diagnóstico , Sarampión/epidemiología , Sarampión/prevención & control , Vacuna contra la Rubéola , Inmunoglobulina M , Inmunoglobulina G , Técnicas para Inmunoenzimas , Brotes de Enfermedades
4.
iScience ; 25(7): 104488, 2022 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-35880029

RESUMEN

Living with HIV infection is associated with early onset of aging-related chronic conditions, sometimes described as accelerated aging. Epigenetic DNA methylation patterns can evaluate acceleration of biological age relative to chronological age. The impact of initial HIV infection on five epigenetic measures of aging was examined before and approximately 3 years after HIV infection in the same individuals (n=102). Significant epigenetic age acceleration (median 1.9-4.8 years) and estimated telomere length shortening (all p≤ 0.001) were observed from pre-to post-HIV infection, and remained significant in three epigenetic measures after controlling for T cell changes. No acceleration was seen in age- and time interval-matched HIV-uninfected controls. Changes in genome-wide co-methylation clusters were also significantly associated with initial HIV infection (p≤ 2.0 × 10-4). These longitudinal observations clearly demonstrate an early and substantial impact of HIV infection on the epigenetic aging process, and suggest a role for HIV itself in the earlier onset of clinical aging.

5.
Cureus ; 13(10): e18462, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34650839

RESUMEN

Syphilis is a multi-organ system bacterial infection caused by the bacterium Treponema pallidum. Syphilis can advance through four clinical stages: primary, secondary, latent, and tertiary. Once in the tertiary stage, mortality is seen in up to 58% of individuals. Here, we present a case of latent neurosyphilis manifesting after initiation of the immunosuppressive medication secukinumab, a monoclonal antibody that antagonizes interleukin-17A. A 66-year-old male with type II diabetes mellitus, hyperlipidemia, and rheumatoid arthritis presented to the emergency department for a right lower quadrant abdominal cellulitis at the site of his insulin pump. On examination, a non-blanching papular rash on the palms and soles with several scaling papules was discovered. No visible pustules, oral lesions, or perirectal lesions were seen. Neurological examination was noncontributory. His past medical history revealed initiation of secukinumab for the management of rheumatoid arthritis two months prior to presentation. The rash developed six weeks after starting secukinumab. Basic laboratory tests, including a complete blood count, thyroid panel, renal function panel, fasting blood glucose, electrolytes, and C-reactive protein, were within normal limits. A hepatic panel revealed mildly elevated alkaline phosphatase, alanine transaminase, and erythrocyte sedimentation rate Westergren level. Laboratory tests for hepatitis B, hepatitis C, HIV-1, Chlamydia trachomatis, and Neisseria gonorrhoeae all returned negative. A rapid plasma reagin (RPR) titer returned positive at 1:128, and a serum Treponema pallidum Ab returned reactive. Lumbar puncture serologies demonstrated a positive Venereal Disease Research Laboratory (VDRL) test. The patient was diagnosed with latent neurosyphilis and started on intravenous crystalline penicillin G for three weeks. A thorough history, comprehensive physical examination, and basic workup should be performed in any individual prior to immunosuppressive medication initiation. On initial presentation, our patient had an isolated rash on the palms and soles, which is classical for secondary syphilis. The specific manifestations seen in syphilis depend upon the timing, site, and immune status of the individual. Due to its ability to have a variety of presentations, syphilis should always remain on the differential for any physician caring for immunocompromised individuals. Again, initiation of immunosuppressive medications, such as the monoclonal antibody secukinumab, can result in the reactivation of previously dormant infections. As physicians, we must carefully screen our patients prior to initiating immunosuppressive agents to prevent disease reactivation.

6.
Front Genet ; 12: 796547, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35295196

RESUMEN

Background: Epigenetic aging is accelerated in tissues of persons living with HIV (PLWH) and may underlie the early onset of age-related illnesses. This study examines the rate-of-change in epigenetic age in PLWH following HIV infection but before HAART, using archived longitudinal samples from the Multicenter AIDS Cohort Study. Methods: DNA was isolated from cryopreserved peripheral blood mononuclear cells from 101 men living with HIV, with baseline visit <2.5 years after HIV seroconversion (Visit 1) and follow-up visit <1.5 years before the initiation of HAART (Visit 2), and 100 HIV-uninfected men matched on age and visits with comparable time intervals. DNA methylation (DNAm) age was estimated for five clocks (Pan-tissue, Extrinsic, Phenotypic, Grim, and Skin & Blood age), and a DNAm-based estimate of telomere length (DNAmTL). Multivariate linear regression models were used to examine baseline factors associated with rate-of-aging, defined as (DNAm age visit 2-DNAm age visit 1)/(age visit 2-age visit 1). Results: Epigenetic age increased approximately twice as fast in PLWH as uninfected controls (Pan-tissue, Extrinsic, and Phenotypic clocks). Shortening of DNAmTL was nearly 3-fold faster in PLWH than controls. Faster rate-of-aging was associated with HIV status (Pan-Tissue, Extrinsic, Phenotypic, and DNAmTL), white race (Extrinsic, DNAmTL), higher cumulative HIV viral load (Grim), and lower baseline DNAm age (Phenotypic, Skin & Blood). Conclusion: Epigenetic rates-of-aging were significantly faster for untreated PLWH. Our findings expand on the important impact of HIV infection on biologic aging, both in elevating epigenetic age and increasing the rate-of-aging in the years following infection.

7.
Pathog Immun ; 5(1): 291-311, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33501399

RESUMEN

BACKGROUND: HIV-1 infection is associated with acceleration of age-related methylation patterns in peripheral blood and brain of infected individuals although the relative contributions of HIV-1 infection versus its treatment to the observed accelerations in biological aging have not yet been investigated. METHODS: In this longitudinal study of the effects of antiretroviral therapy (ART) on epigenetic aging patterns, we extracted DNA from peripheral blood mononuclear cells from 15 HIV-1-infected individuals infected at three time points: 6 months-1year pre-ART, 6-12 months post-initiation of ART, and 18-24 months after initiating ART. We compared these trajectories with those of 15 age-matched uninfected control participants at three time points with similar intervals. Methylation studies were performed using the Infinium methylation 450 arrays. We examined four epigenetic clock measurements: Age acceleration residual (AAR), Extrinsic (EEAA), Phenotypic (PEAA), and Grim (GEAA) epigenetic age acceleration. Weighted correlation network (WGCNA) analysis was used to identify clusters of highly co-methylated CpGs. RESULTS: We found that prior to the initiation of ART all four epigenetic measures were significantly higher in HIV-1-infected individuals compared with uninfected individuals (P<0.001 for AAR, P=0.008 for EEAA, P=0.012 for GEAA, P<0.001 for PEAA using Wilcoxon rank sum tests between serostatus groups). These effects persisted after the initiation of ART, although the magnitude of these differences diminished. At 18-24 months post-ART initiation (time point 3), PEAA and GEAA were no longer significantly different between HIV-1-infected and uninfected individuals (P=0.059 for PEAA, P=0.11 for GEAA), while AAR and EEAA remained significantly higher in HIV-1-infected individuals compared with uninfected individuals. We further examined for global patterns of methylation differences between HIV-1-infected and uninfected at each time point, and found 14 groups of co-methylated CpGs that were significantly different between groups at baseline, and remained different after the initiation of ART. Conclusion: We confirm that epigenetic age acceleration associated with HIV-1 infection is most dramatic before ART initiation, and this observation is consistent across four epigenetic clock measurements, as well as in additional groups of co-methylated CpGs identified using WGCNA. Following initiation of ART, there is a partial reduction in age acceleration in all measures, with loss of any significant difference in PEAA and GEAA between serostatus groups. Our findings support the need for future studies examining for a link between epigenetic age acceleration and clinical outcomes in HIV-1-infected individuals.

8.
Anal Chem ; 91(3): 2506-2515, 2019 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-30676737

RESUMEN

Digital microfluidics (DMF) is a platform that enables highly reconfigurable and automated fluidic operations using a generic device architecture. A unique hallmark of DMF is its "flexibility": a generic device design can be used and reused for many different, divergent fluidic operations. The flexibility of DMF is compromised when devices are permanently modified with embedded sensors. Here we introduce a solution to the "flexibility gap" between fluidic operations in digital microfluidics and embedded sensors: "plug-n-play DMF" (PnP-DMF). In PnP-DMF, devices are designed to allow for rapid and seamless exchange of sensors depending on the application needs. This paper provides "proof of concept" for PnP-DMF using commercial biosensors for glucose and ß-ketone, a custom paper-based electrochemical sensor for lactate, and a generic screen-printed electroanalytical cell. We demonstrate that hot-swapping sensors between experiments allows for convenient implementation of complex processes such as automated analysis of blood samples by standard addition. Finally, we explored the suitability for using PnP sensors in tandem with other sensing modalities, combining biosensor-based electrochemical measurement of glucose with a chemiluminescent magnetic bead-based sandwich immunoassay for insulin. The latter is notable, as it constitutes the first report of an analysis of different analytes in both the supernatant and precipitate from a single sample-aliquot in a microfluidic device. The results presented here highlight the versatility of PnP-DMF, illustrating how it may be useful for a wide range of applications in diagnostics and beyond.

10.
J Glob Radiol ; 4(1)2018.
Artículo en Inglés | MEDLINE | ID: mdl-31633008

RESUMEN

PURPOSE: Training medical providers of different backgrounds the "focused assessment with sonography for HIV-associated TB" (FASH) exam to expand the availability of ultrasound for TB diagnosis in resource poor settings in the central region of Malawi. METHODS AND MATERIALS: A survey was completed by the 19 eligible participants before and after a 4-day training course regarding the utility of the FASH exam. A six-question quiz was used to assess knowledge of the use of ultrasound in the FASH exam before and after the course. RESULTS: Participants' knowledge of the FASH technique significantly improved after the four-day course with a 32% increase in total quiz questions answered correctly (p<0.001).Ninety-five percent (n= 18) of participants answered that they would "likely" incorporate FASH in their clinical practice. Furthermore, 100% (n=19) of participants agreed that the FASH exam would improve their ability to diagnose TB and 95% (n=18) agreed that FASH would improve patient care in their clinic. CONCLUSIONS: After completing a 4-day training course, medical providers were more knowledgeable about the FASH exam and its findings, and felt more comfortable using ultrasound for the diagnosis of TB. Participants were also unanimous in opinion that the FASH ultrasound exam would improve their ability to diagnose TB.

11.
Langmuir ; 32(8): 1939-46, 2016 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-26820229

RESUMEN

Medical ultrasound imaging often employs ultrasound contrast agents (UCAs), injectable microbubbles stabilized by shells or membranes. In tissue, the compressible gas cores can strongly scatter acoustic signals, resonate, and emit harmonics. However, bubbles generated by conventional methods have nonuniform sizes, reducing the fraction that resonates with a given transducer. Microfluidic flow-focusing is an alternative production method which generates highly monodisperse bubbles with uniform constituents, enabling more-efficient contrast enhancement than current UCAs. Production size is tunable by adjusting gas pressure and solution flow rate, but solution effects on downstream stable size and lifetime have not been closely examined. This study therefore investigated several solution parameters, including the DSPC/DSPE-PEG2000 lipid ratio, concentration, viscosity, and preparation temperature to determine their effects on stabilization. It was found that bubble lifetime roughly correlated with stable size, which in turn was strongly influenced by primary-lipid-to-emulsifier ratio, analogous to its effects on conventional bubble yield and Langmuir-trough compressibility in existing studies. Raising DSPE-PEG2000 fraction in solution reduced bubble surface area in proportion to its reduction of lipid packing density at low compression in literature. In addition, the surface area was found to increase proportionately with lipid concentration above 2.1 mM. However, viscosities above or below 2.3-3.3 mPa·s seemed to reduce bubble size. Finally, lipid preparation at room temperature led to smaller bubbles compared to preparation near or above the primary lipid's phase transition point. Understanding these effects will further improve on postformation control over microfluidic bubble production, and facilitate size-tuning for optimal contrast enhancement.


Asunto(s)
Microburbujas , Fosfatidilcolinas/química , Fosfatidiletanolaminas/química , Polietilenglicoles/química , Fluorescencia , Microfluídica , Tamaño de la Partícula , Temperatura de Transición , Viscosidad
12.
PLoS One ; 9(2): e88621, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24558403

RESUMEN

UNLABELLED: Mucosal immunity is central to sexual transmission and overall pathogenesis of HIV-1 infection, but the ability of vaccines to induce immune responses in mucosal tissue compartments is poorly defined. Because macaque vaccine studies suggest that inguinal (versus limb) vaccination may better target sexually-exposed mucosa, we performed a randomized, double-blinded, placebo-controlled Phase I trial in HIV-1-uninfected volunteers, using the recombinant Canarypox (CP) vaccine vCP205 delivered by different routes. 12 persons received vaccine and 6 received placebo, divided evenly between deltoid-intramuscular (deltoid-IM) or inguinal-subcutaneous (inguinal-SC) injection routes. The most significant safety events were injection site reactions (Grade 3) in one inguinal vaccinee. CP-specific antibodies were detected in the blood of all 12 vaccinees by Day 24, while HIV-1-specific antibodies were observed in the blood and gut mucosa of 1/9 and 4/9 evaluated vaccinees respectively, with gut antibodies appearing earlier in inguinal vaccinees (24-180 versus 180-365 days). HIV-1-specific CD8(+) T lymphocytes (CTLs) were observed in 7/12 vaccinees, and blood and gut targeting were distinct. Within blood, both deltoid and inguinal responders had detectable CTL responses by 17-24 days; inguinal responders had early responses (within 10 days) while deltoid responders had later responses (24-180 days) in gut mucosa. Our results demonstrate relative safety of inguinal vaccination and qualitative or quantitative compartmentalization of immune responses between blood and gut mucosa, and highlight the importance of not only evaluating early blood responses to HIV-1 vaccines but also mucosal responses over time. TRIAL REGISTRATION: ClinicalTrials.gov NCT00076817.


Asunto(s)
Vacunas contra el SIDA/administración & dosificación , Vacunas contra el SIDA/uso terapéutico , Virus de la Viruela de los Canarios , Inmunidad Mucosa/inmunología , Vacunas Sintéticas/administración & dosificación , Vacunas Sintéticas/uso terapéutico , Adulto , Linfocitos T CD8-positivos/virología , Músculo Deltoides , Método Doble Ciego , Femenino , Anticuerpos Anti-VIH/sangre , VIH-1 , Humanos , Inmunidad Humoral , Conducto Inguinal , Leucocitos Mononucleares/citología , Masculino , Persona de Mediana Edad , Membrana Mucosa/patología
13.
Lab Chip ; 13(24): 4816-26, 2013 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-24162868

RESUMEN

Ultrasound imaging often calls for the injection of contrast agents, micron-sized bubbles which echo strongly in blood and help distinguish vascularized tissue. Such microbubbles are also being augmented for targeted drug delivery and gene therapy, by the addition of surface receptors and therapeutic payloads. Unfortunately, conventional production methods yield a polydisperse population, whose nonuniform resonance and drug-loading are less than ideal. An alternative technique, microfluidic flow-focusing, is able to produce highly monodisperse microbubbles with stabilizing lipid membranes and drug-carrying oil layers. However, the published 1 kHz production rate for these uniform drug bubbles is very low compared to conventional methods, and must be improved before clinical use can be practical. In this study, flow-focusing production of oil-layered lipid microbubbles was tested up to 300 kHz, with coalescence suppressed by high lipid concentrations or inclusion of Pluronic F68 surfactant in the lipid solution. The transition between geometry-controlled and dripping production regimes was analysed, and production scaling was found to be continuous, with a power trend of exponent ~5/12 similar to literature. Unlike prior studies with this trend, however, scaling curves here were found to be pressure-dependent, particularly at lower pressure-flow equilibria (e.g. <15 psi). Adjustments in oil flow rate were observed to have a similar effect, akin to a pressure change of 1-3 psi. This analysis and characterization of high-speed dual-layer bubble generation will enable more-predictive production control, at rates practical for in vivo or clinical use.


Asunto(s)
Medios de Contraste/química , Portadores de Fármacos/química , Microburbujas , Técnicas Analíticas Microfluídicas/métodos , Gases , Presión , Factores de Tiempo
14.
Bubble Sci Eng Technol ; 4(1): 12-20, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-23049622

RESUMEN

The production of uniform-sized and multilayer microbubbles enables promising medical applications that combine ultrasound contrast and targeted delivery of therapeutics, with improvements in the consistency of acoustic response and drug loading relative to non-uniform populations of microbubbles. Microfluidics has shown utility in the generation of such small multi-phase systems, however low production rates from individual devices limit the potential for clinical translation. We present scaled-up production of monodisperse dual-layered microbubbles in a novel multi-array microfluidic module containing four or eight hydrodynamic flow-focusing orifices. Production reached 1.34 × 10(5) Hz in the 8-channel configuration, and microbubble diameters in the high-speed regime (> 5 × 10(4) Hz) ranged between 18.6-22.3 µm with a mean pooled polydispersity index under 9 percent. Results demonstrate that microfluidic scale-up for high-output production of multilayer bubbles is possible while maintaining consistency in size production, suggesting that this method may be appropriate for future clinical applications.

15.
J Virol ; 86(19): 10505-16, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22811521

RESUMEN

Although HLA-B*57 (B57) is associated with slow progression to disease following HIV-1 infection, B57 heterozygotes display a wide spectrum of outcomes, including rapid progression, viremic slow progression, and elite control. Efforts to identify differences between B57-positive (B57(+)) slow progressors and B57(+) rapid progressors have largely focused on cytotoxic T lymphocyte (CTL) phenotypes and specificities during chronic stages of infection. Although CTL responses in the early months of infection are likely to be the most important for the long-term rate of HIV-1 disease progression, few data on the early CTL responses of eventual slow progressors have been available. Utilizing the Multicenter AIDS Cohort Study (MACS), we retrospectively examined the early HIV-1-specific CTL responses of 14 B57(+) individuals whose time to development of disease ranged from 3.5 years to longer than 25 years after infection. In general, a greater breadth of targeting of epitopes from structural proteins, especially Gag, as well as of highly conserved epitopes from any HIV-1 protein, correlated with longer times until disease. The single elite controller in the cohort was an outlier on several correlations of CTL targeting and time until disease, consistent with reports that elite control is typically not achieved solely by protective HLA-mediated CTLs. When targeting of individual epitopes was analyzed, we found that early CTL responses to the IW9 (ISPRTLNAW) epitope of Gag, while generally subdominant, correlated with delayed progression to disease. This is the first study to identify early CTL responses to IW9 as a correlate of protection in persons with HLA-B*57.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Regulación Viral de la Expresión Génica , VIH-1/metabolismo , Antígenos HLA-B/genética , Síndrome de Inmunodeficiencia Adquirida/sangre , Linfocitos T CD8-positivos/virología , Estudios de Cohortes , Progresión de la Enfermedad , Epítopos/química , Humanos , Masculino , Modelos Estadísticos , Péptidos/química , Fenotipo , Linfocitos T Citotóxicos/citología , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/metabolismo
16.
Lab Chip ; 11(23): 3990-8, 2011 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-22011845

RESUMEN

In this study we report on a microfluidic device and droplet formation regime capable of generating clinical-scale quantities of droplet emulsions suitable in size and functionality for in vivo therapeutics. By increasing the capillary number-based on the flow rate of the continuous outer phase-in our flow-focusing device, we examine three modes of droplet breakup: geometry-controlled, dripping, and jetting. Operation of our device in the dripping regime results in the generation of highly monodisperse liquid perfluoropentane droplets in the appropriate 3-6 µm range at rates exceeding 10(5) droplets per second. Based on experimental results relating droplet diameter and the ratio of the continuous and dispersed phase flow rates, we derive a power series equation, valid in the dripping regime, to predict droplet size, D(d) approximately equal 27(Q(C)/Q(D))(-5/12). The volatile droplets in this study are stable for weeks at room temperature yet undergo rapid liquid-to-gas phase transition, and volume expansion, above a uniform thermal activation threshold. The opportunity exists to potentiate locoregional cancer therapies such as thermal ablation and percutaneous ethanol injection using thermal or acoustic vaporization of these monodisperse phase-change droplets to intentionally occlude the vessels of a cancer.


Asunto(s)
Fluorocarburos/química , Técnicas Analíticas Microfluídicas/métodos , Dimetilpolisiloxanos/química , Técnicas Analíticas Microfluídicas/instrumentación , Tamaño de la Partícula , Transición de Fase , Temperatura
17.
AIDS Res Hum Retroviruses ; 27(4): 391-8, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21087140

RESUMEN

Early HIV-1 infection is marked by rapid evolution of both CD8(+) T lymphocyte (CTL) epitope targeting and viral sequences, while chronic infection demonstrates relative stability of these parameters. To examine the interactions of changing CTL targeting and viremia in early infection, we assessed CTL targeting and viremia levels in persons during early HIV-1 infection (estimated 15-271 days post-infection) who were placed on effective antiretroviral therapy. Pre-therapy, CTL targeting of viral proteins varied between persons depending on time after infection. Across individuals, increasing time after infection was associated with increasing Gag and Pol targeting, suggesting increasing targeting of conserved sequences. The intensity of Gag targeting correlated to lower viremia levels, while Env targeting correlated to higher viremia levels during early infection. This suggested that shifted targeting towards more conserved sequences is involved with the drop of viremia during early infection, consistent with prior observations of correlation between Gag targeting and lower viremia during chronic infection. After suppressive antiretroviral therapy, CTL targeting was generally static, indicating that HIV-1 replication and evolution drives the evolution of CTL targeting in early infection. Overall, these data suggest that early CTL targeting is directed towards more variable epitopes, causing escape and re-targeting until more conserved epitopes are recognized stably in chronic infection. Circumventing this natural history by pre-targeting CTL against more conserved epitopes with a vaccine could minimize the initial period of viral escape and immune damage during acute infection, improving long-term containment of HIV-1.


Asunto(s)
Secuencia Conservada/inmunología , Infecciones por VIH/inmunología , Infecciones por VIH/virología , VIH-1/inmunología , VIH-1/aislamiento & purificación , Linfocitos T Citotóxicos/inmunología , Viremia , Linfocitos T CD8-positivos/inmunología , Epítopos de Linfocito T/inmunología , Humanos , Masculino , Productos del Gen env del Virus de la Inmunodeficiencia Humana/inmunología , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/inmunología , Productos del Gen pol del Virus de la Inmunodeficiencia Humana/inmunología
18.
Endocr Pract ; 15(6): 567-72, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19491073

RESUMEN

OBJECTIVE: To report the case of a patient with multiple endocrine neoplasia type 1 (MEN 1) syndrome with con-comitant parathyroid carcinoma and a classic MEN1 germline mutation. METHODS: We present the clinical findings, laboratory results, imaging studies, and surgical histopathologic features in a woman with MEN 1 syndrome and concomitant parathyroid carcinoma. We also review the literature regarding patients with similar clinical entities and the use of adjuvant radiotherapy for parathyroid carcinoma. RESULTS: A 53-year-old woman presented with nausea and severe primary hyperparathyroidism. Computed tomography revealed parathyroid masses, shown later to be bilateral parathyroid carcinomas and adenomas. Magnetic resonance imaging demonstrated a pituitary macroadenoma, and gastrinomas were confirmed by computed tomography and a secretin stimulation test. She was successfully treated with total thyroidectomy, subtotal parathyroidectomy, and adjuvant radiotherapy. Genetic analysis revealed a classic MEN1 germline mutation. CONCLUSION: This report describes a patient with parathyroid carcinoma occurring in conjunction with MEN 1, further characterizing this rare condition. In contrast to previously described patients, our patient is the first with a classic MEN1 germline mutation, confirming that parathyroid cancer can occur in association with classic MEN 1 genetics.


Asunto(s)
Adenocarcinoma , Gastrinoma , Mutación de Línea Germinal , Neoplasia Endocrina Múltiple Tipo 1 , Neoplasias de las Paratiroides , Adenocarcinoma/genética , Adenocarcinoma/cirugía , Adenocarcinoma/terapia , Femenino , Gastrinoma/genética , Gastrinoma/terapia , Hispánicos o Latinos , Humanos , Hiperparatiroidismo Primario/etiología , Persona de Mediana Edad , Neoplasia Endocrina Múltiple Tipo 1/genética , Neoplasia Endocrina Múltiple Tipo 1/cirugía , Neoplasia Endocrina Múltiple Tipo 1/terapia , Neoplasias de las Paratiroides/genética , Neoplasias de las Paratiroides/cirugía , Neoplasias de las Paratiroides/terapia , Paratiroidectomía , Radioterapia Adyuvante , Tiroidectomía
19.
Cell ; 134(1): 97-111, 2008 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-18614014

RESUMEN

Cholesterol is essential for membrane synthesis; however, the mechanisms that link cellular lipid metabolism to proliferation are incompletely understood. We demonstrate here that cellular cholesterol levels in dividing T cells are maintained in part through reciprocal regulation of the LXR and SREBP transcriptional programs. T cell activation triggers induction of the oxysterol-metabolizing enzyme SULT2B1, consequent suppression of the LXR pathway for cholesterol transport, and promotion of the SREBP pathway for cholesterol synthesis. Ligation of LXR during T cell activation inhibits mitogen-driven expansion, whereas loss of LXRbeta confers a proliferative advantage. Inactivation of the sterol transporter ABCG1 uncouples LXR signaling from proliferation, directly linking sterol homeostasis to the antiproliferative action of LXR. Mice lacking LXRbeta exhibit lymphoid hyperplasia and enhanced responses to antigenic challenge, indicating that proper regulation of LXR-dependent sterol metabolism is important for immune responses. These results implicate LXR signaling in a metabolic checkpoint that modulates cell proliferation and immunity.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo , Transducción de Señal , Esteroles/metabolismo , Linfocitos T/inmunología , Envejecimiento , Animales , Proliferación Celular , Proteínas de Unión al ADN/genética , Humanos , Receptores X del Hígado , Activación de Linfocitos , Ratones , Ratones Endogámicos C57BL , Receptores Nucleares Huérfanos , Receptores Citoplasmáticos y Nucleares/genética , Proteína 2 de Unión a Elementos Reguladores de Esteroles , Linfocitos T/metabolismo
20.
Vaccine ; 26(35): 4617-23, 2008 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-18621451

RESUMEN

Mucosal immune responses induced by HIV-1 vaccines are likely critical for prevention. We report a Phase 1 safety and immunogenicity trial in eight participants using the vaccinia-based TBC-3B vaccine given subcutaneously to determine the relationship between HIV-1 specific systemic and gastrointestinal mucosal responses. Across all subjects, detectable levels of blood vaccinia- and HIV-1-specific antibodies were elicited but none were seen mucosally. While the vaccinia component was immunogenic for CD8(+) T lymphocyte (CTL) responses in both blood and mucosa, it was greater in blood. The HIV-1 component of the vaccine was poorly immunogenic in both blood and mucosa. Although only eight volunteers were studied intensively, the discordance between mucosal and blood responses may highlight mechanisms contributing to recent vaccine failures.


Asunto(s)
Vacunas contra el SIDA/inmunología , Sangre/inmunología , VIH-1/inmunología , Mucosa Intestinal/inmunología , Virus Vaccinia/inmunología , Vacunas contra el SIDA/administración & dosificación , Vacunas contra el SIDA/efectos adversos , Adulto , Anticuerpos Antivirales/análisis , Anticuerpos Antivirales/sangre , Linfocitos T CD8-positivos/inmunología , Femenino , Humanos , Inyecciones Subcutáneas , Masculino , Vacunas Sintéticas/efectos adversos , Vacunas Sintéticas/inmunología
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