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1.
EMBO J ; 41(14): e109958, 2022 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-35670129

RESUMEN

The number of meiotic crossovers is tightly controlled and most depend on pro-crossover ZMM proteins, such as the E3 ligase HEI10. Despite the importance of HEI10 dosage for crossover formation, how HEI10 transcription is controlled remains unexplored. In a forward genetic screen using a fluorescent crossover reporter in Arabidopsis thaliana, we identify heat shock factor binding protein (HSBP) as a repressor of HEI10 transcription and crossover numbers. Using genome-wide crossover mapping and cytogenetics, we show that hsbp mutations or meiotic HSBP knockdowns increase ZMM-dependent crossovers toward the telomeres, mirroring the effects of HEI10 overexpression. Through RNA sequencing, DNA methylome, and chromatin immunoprecipitation analysis, we reveal that HSBP is required to repress HEI10 transcription by binding with heat shock factors (HSFs) at the HEI10 promoter and maintaining DNA methylation over the HEI10 5' untranslated region. Our findings provide insights into how the temperature response regulator HSBP restricts meiotic HEI10 transcription and crossover number by attenuating HSF activity.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas Cromosómicas no Histona/genética , Intercambio Genético , Proteínas de Choque Térmico/metabolismo , Respuesta al Choque Térmico/genética , Meiosis/genética , Ubiquitina-Proteína Ligasas/metabolismo
2.
N Engl J Med ; 387(4): 299-309, 2022 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-35939577

RESUMEN

BACKGROUND: Vitamin D supplements are widely recommended for bone health in the general population, but data on whether they prevent fractures have been inconsistent. METHODS: In an ancillary study of the Vitamin D and Omega-3 Trial (VITAL), we tested whether supplemental vitamin D3 would result in a lower risk of fractures than placebo. VITAL was a two-by-two factorial, randomized, controlled trial that investigated whether supplemental vitamin D3 (2000 IU per day), n-3 fatty acids (1 g per day), or both would prevent cancer and cardiovascular disease in men 50 years of age or older and women 55 years of age or older in the United States. Participants were not recruited on the basis of vitamin D deficiency, low bone mass, or osteoporosis. Incident fractures were reported by participants on annual questionnaires and adjudicated by centralized medical-record review. The primary end points were incident total, nonvertebral, and hip fractures. Proportional-hazards models were used to estimate the treatment effect in intention-to-treat analyses. RESULTS: Among 25,871 participants (50.6% women [13,085 of 25,871] and 20.2% Black [5106 of 25,304]), we confirmed 1991 incident fractures in 1551 participants over a median follow-up of 5.3 years. Supplemental vitamin D3, as compared with placebo, did not have a significant effect on total fractures (which occurred in 769 of 12,927 participants in the vitamin D group and in 782 of 12,944 participants in the placebo group; hazard ratio, 0.98; 95% confidence interval [CI], 0.89 to 1.08; P = 0.70), nonvertebral fractures (hazard ratio, 0.97; 95% CI, 0.87 to 1.07; P = 0.50), or hip fractures (hazard ratio, 1.01; 95% CI, 0.70 to 1.47; P = 0.96). There was no modification of the treatment effect according to baseline characteristics, including age, sex, race or ethnic group, body-mass index, or serum 25-hydroxyvitamin D levels. There were no substantial between-group differences in adverse events as assessed in the parent trial. CONCLUSIONS: Vitamin D3 supplementation did not result in a significantly lower risk of fractures than placebo among generally healthy midlife and older adults who were not selected for vitamin D deficiency, low bone mass, or osteoporosis. (Funded by the National Institute of Arthritis and Musculoskeletal and Skin Diseases; VITAL ClinicalTrials.gov number, NCT01704859.).


Asunto(s)
Colecalciferol , Suplementos Dietéticos , Ácidos Grasos Omega-3 , Fracturas Óseas , Anciano , Colecalciferol/uso terapéutico , Método Doble Ciego , Ácidos Grasos Omega-3/uso terapéutico , Femenino , Fracturas Óseas/epidemiología , Fracturas Óseas/prevención & control , Fracturas de Cadera/epidemiología , Fracturas de Cadera/prevención & control , Humanos , Masculino , Persona de Mediana Edad , Osteoporosis , Deficiencia de Vitamina D
3.
Proc Natl Acad Sci U S A ; 119(35): e2006487119, 2022 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-35998218

RESUMEN

Recent studies have revealed that normal human tissues accumulate many somatic mutations. In particular, human skin is riddled with mutations, with multiple subclones of variable sizes. Driver mutations are frequent and tend to have larger subclone sizes, suggesting selection. To begin to understand the histories encoded by these complex somatic mutations, we incorporated genomes into a simple agent-based skin-cell model whose prime directive is homeostasis. In this model, stem-cell survival is random and dependent on proximity to the basement membrane. This simple homeostatic skin model recapitulates the observed log-linear distributions of somatic mutations, where most mutations are found in increasingly smaller subclones that are typically lost with time. Hence, neutral mutations are "passengers" whose fates depend on the random survival of their stem cells, where a rarer larger subclone reflects the survival and spread of mutations acquired earlier in life. The model can also maintain homeostasis and accumulate more frequent and larger driver subclones if these mutations (NOTCH1 and TP53) confer relatively higher persistence in normal skin or during tissue damage (sunlight). Therefore, a relatively simple model of epithelial turnover indicates how observed passenger and driver somatic mutations could accumulate without violating the prime directive of homeostasis in normal human tissues.


Asunto(s)
Evolución Clonal , Epidermis , Homeostasis , Queratinocitos , Carcinogénesis/genética , Evolución Clonal/genética , Epidermis/metabolismo , Humanos , Queratinocitos/citología , Queratinocitos/fisiología , Mutación , Receptor Notch1/genética , Proteína p53 Supresora de Tumor/genética
4.
J Med Virol ; 96(4): e29558, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38533898

RESUMEN

Human papillomavirus (HPV) infection poses a significant risk to women's health by causing cervical cancer. In addition to HPV, cervical cancer incidence rates can be influenced by various factors, including human immunodeficiency virus and herpes, as well as screening policy. In this study, a mathematical model with stochastic processes was developed to analyze HPV transmission between genders and its subsequent impact on cervical cancer incidence. The model simulations suggest that both-gender vaccination is far more effective than female-only vaccination in preventing an increase in cervical cancer incidence. With increasing stochasticity, the difference between the number of patients in the vaccinated group and the number in the nonvaccinated group diminishes. To distinguish the patient population distribution of the vaccinated from the nonvaccinated, we calculated effect size (Cohen's distance) in addition to Student's t-test. The model analysis suggests a threshold vaccination rate for both genders for a clear reduction of cancer incidence when significant stochastic factors are present.


Asunto(s)
Infecciones por Papillomavirus , Vacunas contra Papillomavirus , Neoplasias del Cuello Uterino , Humanos , Femenino , Masculino , Vacunación , Modelos Biológicos , Virus del Papiloma Humano , Procesos Estocásticos
5.
J Nutr ; 154(4): 1404-1413, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38432561

RESUMEN

BACKGROUND: Blueberries and anthocyanins, their key bioactive component, may improve eye health. However, few long-term studies have examined blueberries and anthocyanins with cataract and age-related macular degeneration (AMD). OBJECTIVES: To investigate the prospective association between blueberry and anthocyanin intake with incident cataract, total AMD, and visually significant AMD among middle-aged and older women. METHODS: A total of 36,653 and 35,402 women initially free of AMD and cataract, respectively, aged ≥45 y from the Women's Health Study provided semiquantitative food frequency questionnaire data on blueberry intake categorized as none, 1-3 servings/mo, 1 serving/wk, or ≥2 servings/wk, plus a combined category of ≥1 serving/wk. Total anthocyanin intake and major subclasses were energy-adjusted and categorized into quintiles. Self-reported risk factors of eye disease were adjusted in multivariable hazard ratios (HRs) (95% confidence intervals [CIs]) of confirmed cataract, AMD, and visually significant AMD with mean follow-up of 11 y. RESULTS: Among the participants, 10.5% consumed ≥1 serving/wk of blueberries, with mean total anthocyanin intake of 11.2 mg/d. Compared to no blueberry intake, women consuming 1-3 servings/mo, 1 serving/wk, and ≥2 servings/wk had corresponding multivariable HRs of total AMD of 0.90 (95% CI: 0.73, 1.11), 0.71 (95% CI: 0.50, 1.00), and 0.36 (95% CI: 0.14, 0.93) (Ptrend = 0.011); those consuming ≥1 servings/wk had an HR of 0.68 (95% CI: 0.47, 0.98). A similar magnitude of HRs were found for visually significant AMD (Ptrend = 0.012) but not for cataract. There were no significant associations between increasing total anthocyanin quintiles and total and visually significant AMD, but there was a modest inverse association with cataract (Ptrend = 0.022), driven by a 10% reduction in cataract in the upper 2 quintiles. CONCLUSIONS: Greater blueberry intake significantly reduced total AMD, but not visually significant AMD or cataract. However, the magnitude of effect for visually significant AMD was similar to total AMD. There was a modest but significant inverse association between dietary anthocyanin intake with cataract but not AMD.


Asunto(s)
Arándanos Azules (Planta) , Catarata , Persona de Mediana Edad , Humanos , Femenino , Anciano , Antocianinas , Estudios de Seguimiento , Factores de Riesgo , Catarata/epidemiología , Catarata/prevención & control
6.
Cell Commun Signal ; 22(1): 8, 2024 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-38167009

RESUMEN

BACKGROUND: Cancer-associated fibroblasts (CAFs) are key components of the tumor microenvironment (TME) that play an important role in cancer progression. Although the mechanism by which CAFs promote tumorigenesis has been well investigated, the underlying mechanism of CAFs activation by neighboring cancer cells remains elusive. In this study, we aim to investigate the signaling pathways involved in CAFs activation by gastric cancer cells (GC) and to provide insights into the therapeutic targeting of CAFs for overcoming GC. METHODS: Alteration of receptor tyrosine kinase (RTK) activity in CAFs was analyzed using phospho-RTK array. The expression of CAFs effector genes was determined by RT-qPCR or ELISA. The migration and invasion of GC cells co-cultured with CAFs were examined by transwell migration/invasion assay. RESULTS: We found that conditioned media (CM) from GC cells could activate multiple receptor tyrosine kinase signaling pathways, including ERK, AKT, and STAT3. Phospho-RTK array analysis showed that CM from GC cells activated PDGFR tyrosine phosphorylation, but only AKT activation was PDGFR-dependent. Furthermore, we found that connective tissue growth factor (CTGF), a member of the CCN family, was the most pronouncedly induced CAFs effector gene by GC cells. Knockdown of CTGF impaired the ability of CAFs to promote GC cell migration and invasion. Although the PDGFR-AKT pathway was pronouncedly activated in CAFs stimulated by GC cells, its pharmacological inhibition affected neither CTGF induction nor CAFs-induced GC cell migration. Unexpectedly, the knockdown of SRC and SRC-family kinase inhibitors, dasatinib and saracatinib, significantly impaired CTGF induction in activated CAFs and the migration of GC cells co-cultured with CAFs. SRC inhibitors restored the reduced expression of epithelial markers, E-cadherin and Zonula Occludens-1 (ZO-1), in GC cells co-cultured with CAFs, as well as CAFs-induced aggregate formation in a 3D tumor spheroid model. CONCLUSIONS: This study provides a characterization of the signaling pathways and effector genes involved in CAFs activation, and strategies that could effectively inhibit it in the context of GC. Video Abstract.


Asunto(s)
Fibroblastos Asociados al Cáncer , Factor de Crecimiento del Tejido Conjuntivo , Neoplasias Gástricas , Humanos , Fibroblastos Asociados al Cáncer/metabolismo , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Factor de Crecimiento del Tejido Conjuntivo/metabolismo , Fibroblastos/metabolismo , Proteínas Tirosina Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal , Neoplasias Gástricas/metabolismo , Microambiente Tumoral
7.
Support Care Cancer ; 32(3): 156, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38349581

RESUMEN

PURPOSE: Despite proven benefits, few cancer patients exercise during chemotherapy. The American College of Sports Medicine's Exercise is Medicine® (EIM) initiative describes a model to integrate exercise into oncology care, based upon assessing patients' ability to exercise safely, advising on exercise benefits, and referring patients to exercise. We developed and tested a strategy to implement EIM in a community-based oncology clinic, to assess-advise-refer 20 patients undergoing chemotherapy to a 3-month online exercise class, and measured implementation outcomes. METHODS: Using a community-based provider participation in research (CBPPR) model, researchers and staff co-designed and tested a 4-level implementation strategy, with a goal of assessing-advising-referring 20 cancer patients to exercise. Surveys and interviews were conducted with 12 (100%) staff at baseline and post-implementation on acceptability/appropriateness/feasibility, perceptions of individual implementation roles, and organizational strengths/conditions. Data were analyzed using correlations, t-tests, and content analysis. RESULTS: The proposed strategy was revised in collaboration with staff who requested assistance for recruitment and data collection. EIM was successfully implemented with 41 (92%) patients assessed, 37 (90%) advised, and 22 (60%) referred to exercise classes. Barriers to implementation were staff shortages and time constraints; facilitators included research team supports. Staff's perceived organizational strengths were positively correlated with exercise promotion acceptability, appropriateness, and feasibility. There were no statistically significant changes in implementation outcomes (acceptability/appropriateness/feasibility) post-implementation. CONCLUSIONS: Using a collaborative model, EIM was successfully implemented in a community oncology clinic; however, the clinic required significant support from the research team. Adaptations to the EIM process may be required to improve implementation outcomes.


Asunto(s)
Neoplasias , Medicina Deportiva , Deportes , Humanos , Ejercicio Físico , Oncología Médica , Neoplasias/terapia
8.
J Arthroplasty ; 39(8): 2068-2073, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38492823

RESUMEN

BACKGROUND: Long-term (minimum 19-year) outcome data on clinical results and patient satisfaction after posterior-stabilized total knee arthroplasties (TKAs) are missing in the literature. The purpose of the study was to evaluate the clinical and radiographic results as well as patient satisfaction at a mean of 21.2 years after posterior-stabilized TKAs. METHODS: This study included 756 patients (1,350 knees) who had undergone TKAs. There were 96 men and 660 women (mean age, 58 years; range, 40 to 84). The mean follow-up was 21.2 years (range, 19 to 23). At each follow-up visit, the patients were assessed radiographically and clinically. Furthermore, patient satisfaction was determined. RESULTS: The Knee Society total, pain, function, and deformity scores were 42, 18, 33, and 5 points, respectively, at the final follow-up. The mean Western Ontario and McMaster Universities Arthritis Index score was 25 points at the final follow-up. With revision or aseptic loosening as the end point, the 23-year intimated survival for the implant was 96% (95% confidence interval, 91 to 100%). The overall patient satisfaction score at the final follow-up was 83.3 points (range, 81 to 86). Patient satisfaction scores with regard to pain, housework, recreation, and surgery were 84, 81, 82, and 86 points, respectively. CONCLUSIONS: The findings of the present, mean 21-year follow-up clinical study suggest excellent results with regard to the revision rates and survivorship of the posterior-stabilized total knee implants. However, consistent with the literature, we found that about 80% of patients expressed overall satisfaction with their primary TKAs. About 8% of patients were either somewhat or very dissatisfied with the procedure.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Satisfacción del Paciente , Humanos , Femenino , Masculino , Persona de Mediana Edad , Adulto , Anciano , Estudios de Seguimiento , Anciano de 80 o más Años , Resultado del Tratamiento , Articulación de la Rodilla/cirugía , Radiografía , Prótesis de la Rodilla , Falla de Prótesis , Reoperación/estadística & datos numéricos
9.
Gerodontology ; 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38720436

RESUMEN

BACKGROUND AND OBJECTIVES: Poor oral health disproportionately affects low-income older adults, for whom food insecurity and poor mental health may affect dental health. We explored the associations between food insecurity, mental health, and dental health. Furthermore, we examined whether mental health impacted the associations between food insecurity and dental health. MATERIALS AND METHODS: We conducted a cross-sectional study with a convenience sample of 226 older adults (aged 50+), employing survey and dental screening data. Participants were recruited from seven community-based organisations in Washington State, USA. We calculated descriptive statistics and conducted Chi-square tests, t tests, and logistic regression analyses to assess the associations between aspects of dental health (untreated decay, gum disease, and unmet dental needs), mental health (depression and cognitive function), and food insecurity. RESULTS: In our sample, food insecurity was observed in 28.4%, 40.6% had untreated decay, 31.6% gum disease, and 42.5% unmet dental needs. Food insecurity was associated with a higher occurrence of untreated decay and unmet dental needs. Participants experiencing food insecurity had higher odds of gum disease (aOR = 2.3; 95% CI: 1.1, 5.2) and unmet dental needs (aOR = 3.2; 95% CI:1.4, 7.6). Greater gum disease due to food insecurity was observed among individuals with lower levels of cognitive impairment. CONCLUSION: Food insecurity is associated with poorer oral health among older adults and cognitive function may modify this relationship. These findings underscore the importance of addressing both food insecurity and cognitive impairment as integral components of efforts to improve the oral health of older adults.

10.
Small ; 19(26): e2207117, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36960666

RESUMEN

African swine fever virus (ASFV) is a severe and persistent threat to the global swine industry. As there are no vaccines against ASFV, there is an immense need to develop easy-to-use, cost-effective, and rapid point-of-care (POC) diagnostic platforms to detect and prevent ASFV outbreaks. Here, a novel POC diagnostic system based on affinity column chromatography for the optical detection of ASFV is presented. This system employs an on-particle hairpin chain reaction to sensitize magnetic nanoclusters with long DNA strands in a target-selective manner, which is subsequently fed into a column chromatography device to produce quantitatively readable and colorimetric signals. The detection approach does not require expensive analytical apparatus or immobile instrumentation. The system can detect five genes constituting the ASFV whole genome with a detection limit of ≈19.8 pm in swine serum within 30 min at laboratory room temperature. With an additional pre-amplification step using polymerase chain reaction (PCR), the assay is successfully applied to detect the presence of ASFV in 30 suspected swine samples with 100% sensitivity and specificity, similar to quantitative PCR. Thus, this simple, inexpensive, portable, robust, and customizable platform for the early detection of ASFV can facilitate the timely surveillance and implementation of control measures.


Asunto(s)
Virus de la Fiebre Porcina Africana , Fiebre Porcina Africana , Porcinos , Animales , Virus de la Fiebre Porcina Africana/genética , Fiebre Porcina Africana/diagnóstico , Reacción en Cadena de la Polimerasa/métodos , Cromatografía de Afinidad , Sensibilidad y Especificidad , Fenómenos Magnéticos
11.
J Urol ; 209(1): 243-252, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36067369

RESUMEN

PURPOSE: Our goal was to evaluate vitamin D supplementation for preventing or treating overactive bladder and urinary incontinence in men. MATERIALS AND METHODS: Ancillary study of men aged ≥55 years in VITAL (VITamin D and OmegA-3 TriaL). Randomized treatments included: vitamin D3 (cholecalciferol), marine omega-3 fatty acids, or matching placebo. Structured urinary incontinence questions measured the prevalence of overactive bladder at year 5 and urinary incontinence at years 2 and 5, along with incidence and progression of urinary incontinence from years 2 to 5. Prespecified subgroup analyses examined men with low baseline serum 25-hydroxyvitamin D (<20 ng/mL). RESULTS: Among the 11,486 men who provided data at year 2 and 10,474 at year 5, mean age was 68 years at year 2, with 23% racial/ethnic minorities. In primary analyses, vitamin D supplementation compared to placebo did not lower odds of overactive bladder at year 5 (OR 0.97, 95% CI 0.87-1.08) or weekly urinary incontinence at year 2 (OR 0.94, 95% CI 0.83-1.05) or year 5 (OR 0.98, 95% CI 0.88-1.09). We found interactions of baseline serum 25-hydroxyvitamin D level with vitamin D supplementation for overactive bladder (P value for interaction = .001), and secondarily, for any urinary incontinence at year 2 (P value for interaction = .05). Men with baseline 25-hydroxyvitamin D <20 ng/mL, who were assigned to vitamin D supplements, had lower odds of overactive bladder (OR 0.51, 95% CI 0.35-0.76) compared to placebo, yet higher odds of any urinary incontinence (OR 1.24, 95% CI 0.93-1.64). CONCLUSIONS: Overall, vitamin D supplementation did not improve overactive bladder or urinary incontinence compared to placebo. However, specific use of vitamin D in men with lower 25-hydroxyvitamin D levels had inconsistent findings.


Asunto(s)
Vejiga Urinaria Hiperactiva , Incontinencia Urinaria , Humanos , Anciano , Vejiga Urinaria Hiperactiva/tratamiento farmacológico , Vejiga Urinaria Hiperactiva/epidemiología , Incontinencia Urinaria/epidemiología , Incontinencia Urinaria/etiología , Incontinencia Urinaria/prevención & control , Vitamina D/uso terapéutico
12.
Nat Chem Biol ; 17(1): 104-112, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33139950

RESUMEN

Tyrian purple, mainly composed of 6,6'-dibromoindigo (6BrIG), is an ancient dye extracted from sea snails and was recently demonstrated as a biocompatible semiconductor material. However, its synthesis remains limited due to uncharacterized biosynthetic pathways and the difficulty of regiospecific bromination. Here, we introduce an effective 6BrIG production strategy in Escherichia coli using tryptophan 6-halogenase SttH, tryptophanase TnaA and flavin-containing monooxygenase MaFMO. Since tryptophan halogenases are expressed in highly insoluble forms in E. coli, a flavin reductase (Fre) that regenerates FADH2 for the halogenase reaction was used as an N-terminal soluble tag of SttH. A consecutive two-cell reaction system was designed to overproduce regiospecifically brominated precursors of 6BrIG by spatiotemporal separation of bromination and bromotryptophan degradation. These approaches led to 315.0 mg l-1 6BrIG production from tryptophan and successful synthesis of regiospecifically dihalogenated indigos. Furthermore, it was demonstrated that 6BrIG overproducing cells can be directly used as a bacterial dye.


Asunto(s)
Proteínas de Escherichia coli/genética , Escherichia coli/genética , FMN Reductasa/genética , Regulación Bacteriana de la Expresión Génica , Indoles/metabolismo , Oxidorreductasas/genética , Oxigenasas/genética , Triptófano/metabolismo , Triptofanasa/genética , Materiales Biocompatibles/química , Materiales Biocompatibles/metabolismo , Clonación Molecular , Colorantes/aislamiento & purificación , Colorantes/metabolismo , Escherichia coli/enzimología , Proteínas de Escherichia coli/metabolismo , FMN Reductasa/metabolismo , Flavina-Adenina Dinucleótido/análogos & derivados , Flavina-Adenina Dinucleótido/metabolismo , Expresión Génica , Vectores Genéticos/química , Vectores Genéticos/metabolismo , Halogenación , Carmin de Índigo/aislamiento & purificación , Carmin de Índigo/metabolismo , Indoles/aislamiento & purificación , Ingeniería Metabólica/métodos , Oxidorreductasas/metabolismo , Oxigenasas/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Semiconductores , Estereoisomerismo , Triptofanasa/metabolismo
13.
PLoS Comput Biol ; 18(3): e1009919, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35263336

RESUMEN

A long-standing practice in the treatment of cancer is that of hitting hard with the maximum tolerated dose to eradicate tumors. This continuous therapy, however, selects for resistant cells, leading to the failure of the treatment. A different type of treatment strategy, adaptive therapy, has recently been shown to have a degree of success in both preclinical xenograft experiments and clinical trials. Adaptive therapy is used to maintain a tumor's volume by exploiting the competition between drug-sensitive and drug-resistant cells with minimum effective drug doses or timed drug holidays. To further understand the role of competition in the outcomes of adaptive therapy, we developed a 2D on-lattice agent-based model. Our simulations show that the superiority of the adaptive strategy over continuous therapy depends on the local competition shaped by the spatial distribution of resistant cells. Intratumor competition can also be affected by fibroblasts, which produce microenvironmental factors that promote cancer cell growth. To this end, we simulated the impact of different fibroblast distributions on treatment outcomes. As a proof of principle, we focused on five types of distribution of fibroblasts characterized by different locations, shapes, and orientations of the fibroblast region with respect to the resistant cells. Our simulation shows that the spatial architecture of fibroblasts modulates tumor progression in both continuous and adaptive therapy. Finally, as a proof of concept, we simulated the outcomes of adaptive therapy of a virtual patient with four metastatic sites composed of different spatial distributions of fibroblasts and drug-resistant cell populations. Our simulation highlights the importance of undetected metastatic lesions on adaptive therapy outcomes.


Asunto(s)
Neoplasias , Simulación por Computador , Fibroblastos , Humanos , Dosis Máxima Tolerada , Neoplasias/tratamiento farmacológico , Neoplasias/patología
14.
Analyst ; 148(2): 316-327, 2023 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-36484412

RESUMEN

Most nucleic acid biosensors employ nucleic acid-processing enzymes to bind, degrade, splice, synthesize, and modify nucleic acids. Utilizing their unique substrate preference, binding mode, and catalytic activity is of great importance in designing nucleic acid biosensors. Combination with DNA-processing enzymes enables them to transform into a new generation of molecular diagnostics tools with enhanced selectivity and sensitivity and reduced reaction time. Here, we report an isothermal amplification strategy by coemploying a structure-specific endonuclease (flap endonuclease 1, FEN1) and a strand-displacing DNA polymerase (Bst DNA polymerase) to detect long RNA targets. This approach couples the FEN1-driven invasive cleavage reaction with toehold-mediated rolling circle amplification (iFEN-tRCA), enabling the highly selective and rapid detection of long RNA targets and offering a detection limit below 10 pM within 1 h. We used two targets, such as human epidermal growth factor receptor 2 (HER2, encoded by ERBB2) and dopamine- and cyclic AMP-regulated phosphoprotein (DARPP, encoded by PPP1R1B), associated with prognosis or response to anticancer therapy. We demonstrated the feasibility and quantitative capability of the iFEN-tRCA assay by assessing the expression of two RNA transcripts (ERBB2 and PPP1R1B) with total RNA extracts purified from human breast cancer cells. Therefore, we envision that the developed assay will provide a suitable prognostic and diagnostic tool for identifying appropriate patients for HER2-targeted therapy and predicting the clinical outcome and occurrence of metastasis relapse in breast cancer.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/genética , Transcriptoma , Técnicas de Amplificación de Ácido Nucleico , ADN/genética , ADN/metabolismo , ADN Polimerasa Dirigida por ADN/química , ARN
15.
Hum Resour Health ; 21(1): 89, 2023 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-37990265

RESUMEN

BACKGROUND: Achieving the targeted organizational goals through effective training can increase employee satisfaction. Since 2015, the Supranational Reference Laboratory Uganda (SRL Uganda) has trained National Tuberculosis Reference Laboratories (NTRLs) from 21 countries in a variety of areas that cover both technical and programmatic aspects pertinent to TB laboratories. The Laboratory Quality Management System (LQMS) under SRL coordinates actions intended to ensure sustained quality of the laboratory services offered by the National TB Reference Laboratories. In order for laboratory results to be helpful in a clinical or public health setting, they must be accurate, reliable, and timely. The LQMS course aims to provide learners with knowledge on how to attain and maintain this quality. Prior to this study, there was hardly any data available on the effectiveness of LQMS trainings provided by SRL Uganda; using Kirkpatrick model, which is popular among researchers for evaluating the efficacy of the training program, this paper seeks to establish the effectiveness of the LQMS training offered by the SRL Uganda. METHOD: We evaluated the effectiveness of LQMS training within the Uganda's SRL network for courses offered during the period 2017 and 2021 for participants from the Southern and East African sub-Saharan region. RESULTS: In 2017 and 2021, respectively, test results from 10/17 and 9/17 showed overall post-test scores above 80%. Of the 18 labs evaluated, 14 showed improvement; of these, 7 labs were from the Eastern region and the other 7 were from Southern Africa; one facility in this region also maintained its accreditation. In the post-evaluation assessment, attendees of the LQMS course gave feedback of strongly agree and agree variety. CONCLUSION: More SRL Uganda network laboratories in the regions achieved a 5-star SLIPTA level rating and among these, 5 NTRLs got ISO 15189:2012 accredited by the end of 2021, while one maintained its accreditation status. This proves that the Laboratory Quality Management System training program was an effective tool in improving the quality of laboratory services, work practices, and processes.


Asunto(s)
Laboratorios , Tuberculosis , Humanos , Uganda , Tuberculosis/diagnóstico , Tuberculosis/tratamiento farmacológico , Encuestas y Cuestionarios , África del Norte
16.
BMC Anesthesiol ; 23(1): 132, 2023 04 22.
Artículo en Inglés | MEDLINE | ID: mdl-37085760

RESUMEN

BACKGROUND: Remimazolam is a recently approved, ultra-short-acting benzodiazepine. However, few studies have investigated remimazolam in relation to postoperative nausea and vomiting (PONV). This study aimed to compare the effects of remimazolam and propofol on PONV in patients undergoing oral and maxillofacial surgery. METHODS: Patients (n = 206) aged 19-65 years who were scheduled for oral and maxillofacial surgery were randomized into two groups, the remimazolam (R) and propofol group (P). In the R group (n = 94), remimazolam was used to induce anesthesia at 12 mg/kg/h and to maintain anesthesia at 1-2 mg/kg/h. In the P group (n = 95), anesthesia was induced and maintained with propofol (target effect-site concentration: 3-5 µg/ml). In both groups, remifentanil was administered at a target effect-site concentration of 2.5-4 ng/ml. The primary outcome was the overall incidence of PONV during the first 24 h after surgery. Secondary outcomes included the severity of nausea, use of rescue antiemetics, severity of postoperative pain, use of rescue analgesia, and quality of recovery. RESULTS: The incidence of PONV during the first 24 h after surgery was 11.7% and 10.5% in the R group and P group, respectively, and there was no significant difference in the severity of nausea (P > 0.05). Ten patients in the R group and ten patients in the P group required rescue antiemetics during the first 24 h after surgery (P = 0.98). No inter-group differences were observed in terms of postoperative pain score, use of rescue analgesia, and quality of recovery (P > 0.05). CONCLUSIONS: In this study, remimazolam did not increase the incidence and severity of PONV compared with propofol. TRIAL REGISTRATION: KCT0006965, Clinical Research Information Service (CRIS), Republic of Korea. Registration date: 26/01/2022.


Asunto(s)
Antieméticos , Propofol , Cirugía Bucal , Humanos , Náusea y Vómito Posoperatorios/inducido químicamente , Náusea y Vómito Posoperatorios/epidemiología , Propofol/efectos adversos , Antieméticos/efectos adversos , Estudios Prospectivos , Benzodiazepinas , Dolor Postoperatorio/inducido químicamente
17.
Biotechnol Lett ; 45(5-6): 589-600, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36971774

RESUMEN

OBJECTIVES: S100A8 is highly expressed in several inflammatory and oncological conditions. To address the current lack of a reliable and sensitive detection method for S100A8, we generated a monoclonal antibody with a high binding affinity to human S100A8 to enable early disease diagnosis. RESULTS: A soluble recombinant S100A8 protein with a high yield and purity was produced using Escherichia coli. Next, mice were immunized with recombinant S100A8 to obtain anti-human S100A8 monoclonal antibodies using hybridoma technology. Lastly, the high binding activity of the antibody was confirmed and its sequence was identified. CONCLUSIONS: This method, including the production of antigens and antibodies, will be useful for the generation of hybridoma cell lines that produce anti-S100A8 monoclonal antibodies. Moreover, the sequence information of the antibody can be used to develop a recombinant antibody for use in various research and clinical applications.


Asunto(s)
Anticuerpos Monoclonales , Calgranulina A , Animales , Ratones , Anticuerpos Monoclonales/química , Hibridomas , Línea Celular , Proteínas Recombinantes/genética , Biomarcadores
18.
Altern Ther Health Med ; 29(2): 50-57, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36525354

RESUMEN

Background: Electroacupuncture (EA) has been known to exert analgesic effects according to several reports, but studies investigating the analgesic effect of EA using the quantitative sensory test (QST) are rare. Primary Study Objective: To investigate the analgesic effects of electroacupuncture through changes in thermal thresholds measured using the QST. Design: Pilot, randomized, single-blind, parallel design. Setting: The study was conducted at Dongguk University Bundang Oriental Hospital (DUBOH) in South Korea. Participants: We included 40 healthy participants age 20 to 40 years. Intervention: The EA group received EA for 30 minutes at 6 acupuncture points (LI4, PC6, LI10, LI11, ST36, and SP6) and the control group just rested. Outcome measures: The primary outcome measure was 4 thermal thresholds including warm detection (WDT), cold detection (CDT), hot pain (HPT), and cold pain (CPT) measured using QST at baseline and after 15, 30 and 60 minutes. The secondary outcomes were the intensity of acupuncture sensation (visual analogue scale [VAS]) and De-qi (Massachusetts General Hospital Acupuncture Sensation Scale [MASS]). Results: The EA group showed significant changes in HPT (P < .001) and CPT (P = .049) compared with the control group, whereas WDT and CDT did not significantly differ. Furthermore, the changes in thermal thresholds were more pronounced in the higher intensity acupuncture sensation group (VAS ≥40) than in the lower intensity group (VAS < 40), although not significantly. The high De-qi group presented greater changes in WDT, CDT, HPT and CPT than the low De-qi group, as measured using MASS. It was especially statistically significant at HPT a feeling of "heaviness" and "dull pain" and at CDT of "tingling." We observed no adverse events related to the study. Conclusion: The change in thermal pain thresholds effected by EA supports the analgesic effect of EA reported in previous studies. The underlying mechanisms need to be holistically considered, and further studies are needed for definitive evidence.


Asunto(s)
Electroacupuntura , Adulto , Humanos , Adulto Joven , Puntos de Acupuntura , Analgésicos , Dolor , Método Simple Ciego
19.
J Arthroplasty ; 38(5): 873-879, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36410630

RESUMEN

BACKGROUND: The rate of failure of cemented and cementless total hip arthroplasty (THA) in younger patients is higher than that in elderly patients. The purpose of this study is to document the long-term clinical results of THA with the so-called third-generation cementing and the results of second-generation cementless THA in patients <50 years of age. METHODS: This study included 106 patients who had had bilateral THA with a cemented stem in one hip and a cementless stem in the other. There were 78 men and 28 women. Their mean age was 47 years (range, 21-49). The average follow-up duration was 31 years (range, 30-32.5). RESULTS: There were similar mean Harris Hip Scores (90 versus 91 points) between the groups at the final follow-up. Forty-six acetabular components (43%) in the cemented group and 48 acetabular components (45%) in the cementless group were revised. Five femoral components (5%) in the cemented group and 4 femoral components (4%) in the cementless group were revised. Survivorship of the acetabular component at 30.8 years was similar in both groups (57% in the cemented group versus 55% in the cementless group). Survivorship of the femoral component at 30.8 years was also similar in both groups (95% in the cemented group versus 96% in the cementless group). CONCLUSION: Long-term fixation of the cemented or cementless femoral stem was outstanding. There was a high rate of the acetabular component revision due to conventional polyethylene wear and periacetabular osteolysis in both hybrid and fully cementless THA groups.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Prótesis de Cadera , Masculino , Humanos , Femenino , Anciano , Persona de Mediana Edad , Artroplastia de Reemplazo de Cadera/métodos , Resultado del Tratamiento , Estudios de Seguimiento , Falla de Prótesis , Cementos para Huesos , Polietileno , Reoperación , Diseño de Prótesis
20.
J Arthroplasty ; 38(2): 286-292, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36028177

RESUMEN

BACKGROUND: Application of highly cross-linked polyethylene (HXLPE) to a posterior cruciate-substituting total knee arthroplasty (TKA) might add the risk of fracture and failure of the tibial polyethylene insert. The purpose of this study is to evaluate the long-term (up to 19 years) clinical and radiographic results of posterior cruciate-substituting TKAs with HXLPE or conventional polyethylene. METHODS: This study analyzed the results of 1,217 patients (444 men and 773 women; mean age of 65 ± 7 years, range, 31-85) (2,434 knees) who had received a NexGen LPS-Flex prosthesis with a conventional tibial insert in one knee and the same prosthesis with an HXLPE tibial insert in the contralateral knee. The mean duration of follow-up was 17 years (range, 15-19). RESULTS: The 2 groups did not differ significantly (P > .05) with regard to the clinical and radiographic results. No knee in either group had a fracture of the tibial polyethylene post or failure of the locking mechanism of the tibial polyethylene insert or osteolysis. Twenty-eight knees (2.3%) in the HXLPE group and 26 knees (2.1%) in the conventional polyethylene group were revised. The estimated survival rate at 17 years was 97.7% in the HXLPE group and 97.9% in the conventional polyethylene group. CONCLUSION: The data suggest that clinical and radiographic findings at a mean of 17 years after posterior cruciate-substituting TKA are the same for patients treated with HXLPE and those treated with conventional polyethylene.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Fracturas Óseas , Prótesis de la Rodilla , Masculino , Humanos , Femenino , Persona de Mediana Edad , Anciano , Artroplastia de Reemplazo de Rodilla/métodos , Polietileno , Diseño de Prótesis , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/cirugía , Fracturas Óseas/cirugía , Falla de Prótesis
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