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1.
Pathogens ; 12(8)2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37623966

RESUMEN

The presence of fungi in the indoor environment is associated with allergies and other respiratory symptoms. The aim of this study was to use sequencing and molecular methods, including next-generation sequencing (NGS) approaches, to explore the bacterial and fungal communities and their abundance in the indoor environment of houses (n = 20) with visible "moldy" (HVM) and nonvisible "non-moldy" (HNM) in Memphis, TN, USA. Dust samples were collected from air vents and ground surfaces, and the total DNA was analyzed for bacteria and fungi by amplifying 16S rRNA and ITS genes on the Illumina Miseq. Results indicated that Leptosphaerulina was the most abundant fungal genus present in the air vent and ground samples from HNM and HVM. At the same time, the most abundant bacterial genera in the air vent and ground samples were Propionibacterium and Streptococcus. The fungi community diversity was significantly different in the air vent samples. The abundance of fungal species known to be associated with respiratory diseases in indoor dust samples was similar, regardless of the visibility of fungi in the houses. The existence of fungi associated with respiratory symptoms was compared with several parameters like dust particulate matter (PM), CO2 level, temperature, and humidity. Most of these parameters are either positively or negatively correlated with the existence of fungi associated with respiratory diseases; however, none of these correlations were significant at p = 0.05. Our results indicate that implementing molecular methods for detecting indoor fungi may strengthen common exposure and risk assessment practices.

2.
Front Microbiol ; 14: 1275374, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38179448

RESUMEN

The composition of resident microbes in the human body is linked to various diseases and their treatment outcomes. Although studies have identified pancreatic ductal adenocarcinoma (PDAC)-associated bacterial communities in the oral and gut samples, herein, we hypothesize that the prevalence of microbiota in pancreatic tumor tissues is different as compared with their matched adjacent, histologically normal appearing tissues, and these microbial molecular signatures can be highly useful for PDAC diagnosis/prognosis. In this study, we performed comparative profiling of bacterial populations in pancreatic tumors and their respective adjacent normal tissues using 16S rRNA-based metagenomics analysis. This study revealed a higher abundance of Proteobacteria and Actinomycetota in tumor tissues compared with adjacent normal tissues. Interestingly, the linear discriminant analysis (LDA) scores unambiguously revealed an enrichment of Delftia in tumor tissues, whereas Sphingomonas, Streptococcus, and Citrobacter exhibited a depletion in tumor tissues. Furthermore, we analyzed the microbial composition between different groups of patients with different tumor differentiation stages. The bacterial genera, Delftia and Staphylococcus, were very high at the G1 stages (well differentiated) compared with G2 (well to moderate/moderately differentiated) and G3/G4 (poorly differentiated) stages. However, the abundance of Actinobacter and Cloacibacterium was found to be very high in G2 and G3, respectively. Additionally, we evaluated the correlation of programmed death-ligand (PDL1) expression with the abundance of bacterial genera in tumor lesions. Our results indicated that three genera such as Streptomyces, Cutibacterium, and Delftia have a positive correlation with PD-L1 expression. Collectively, these findings demonstrate that PDAC lesions harbor relatively different microbiota compared with their normal tumor adjacent tissues, and this information may be helpful for the diagnosis and prognosis of PADC patients.

3.
ACS Omega ; 8(42): 38839-38848, 2023 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-37901538

RESUMEN

Aberrant regulation of ß-catenin signaling is strongly linked with cancer proliferation, invasion, migration, and metastasis, thus, small molecules that can inhibit this pathway might have great clinical significance. Our molecular modeling studies suggest that ormeloxifene (ORM), a triphenylethylene molecule that docks with ß-catenin, and its brominated analogue (Br-ORM) bind more effectively with relatively less energy (-7.6 kcal/mol) to the active site of ß-catenin as compared to parent ORM. Herein, we report the synthesis and characterization of a Br-ORM by NMR and FTIR, as well as its anticancer activity in cervical cancer models. Br-ORM treatment effectively inhibited tumorigenic features (cell proliferation and colony-forming ability, etc.) and induced apoptotic death, as evident by pronounced PARP cleavage. Furthermore, Br-ORM treatment caused cell cycle arrest at the G1-S phase. Mechanistic investigation revealed that Br-ORM targets the key proteins involved in promoting epithelial-mesenchymal transition (EMT), as demonstrated by upregulation of E-cadherin and repression of N-cadherin, Vimentin, Snail, MMP-2, and MMP-9 expression. Br-ORM also represses the expression and nuclear subcellular localization of ß-catenin. Consequently, Br-ORM treatment effectively inhibited tumor growth in an orthotopic cervical cancer xenograft mouse model along with EMT associated changes as compared to vehicle control-treated mice. Altogether, experimental findings suggest that Br-ORM is a novel, promising ß-catenin inhibitor and therefore can be harnessed as a potent anticancer small molecule for cervical cancer treatment.

4.
J Appl Clin Med Phys ; 12(1): 3311, 2010 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-21330977

RESUMEN

We report on our initial experience with daily image guidance for the treatment of a patient with a basal cell carcinoma of the nasal dorsum using bolus electron conformal therapy. We describe our approach to daily alignment using treatment machine-integrated megavoltage (MV) planar imaging in conjunction with cone beam CT (CBCT) volumetric imaging to ensure the best possible setup reproducibility. Based on MV imaging, beam aperture misalignment with the intended treatment region was as large as 0.5 cm in the coronal plane. Four of the five fractions analyzed show induced shifts when compared to digitally reconstructed radiographs (DRR), in the range of 0.2-0.5 cm. Daily inspection of CBCT images show that the bolus device can have significant tilt in any given direction by as much as 13° with respect to beam axis. In addition, we show that CBCT images reveal air gaps between bolus and skin that vary from day to day, and can potentially degrade surface dose coverage. Retrospective dose calculation on CBCT image sets shows that when daily shifts based on MV imaging are not corrected, geometrical miss of the planning target volume (PTV) can cause an underdosing as large as 14% based on DVH analysis of the dose to the 90% of the PTV volume.


Asunto(s)
Tomografía Computarizada de Haz Cónico/métodos , Neoplasias Nasales/radioterapia , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia Conformacional/métodos , Algoritmos , Electrones/uso terapéutico , Humanos , Dosificación Radioterapéutica
5.
Pract Radiat Oncol ; 10(5): e425-e431, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32004703

RESUMEN

PURPOSE: Treating critically ill patients in radiation oncology departments poses multiple safety risks. This study describes a method to improve the speed of radiation treatment for patients in the intensive care unit by eliminating the need for computed tomography (CT) simulation or on-table treatment planning using patients' previously acquired diagnostic CT scans. METHODS AND MATERIALS: Initially, a retrospective planning study was performed to assess the applicability and safety of diagnostic scan-based planning (DSBP) for 3 typical indications for radiation therapy in patients in the intensive care unit: heterotopic ossification (10), spine metastases (cord compression; 10), and obstructive lung lesions (5). After identification of an appropriate diagnostic CT scan, treatment planning was performed using the diagnostic scan data set. These treatment plans were then transferred to the patients' simulation scans, and a dosimetric comparison was performed between the 2 sets of plans. Additionally, a time study of the first 10 patients treated with DSBP in our department was performed. RESULTS: The retrospective analysis demonstrated that DSBP resulted in treatment plans that, when transferred to the CT simulation data sets, provided excellent target coverage, a median D95% of 96% (range, 86%-100%) of the prescription dose with acceptable hot spots, and a median Dmax108% (range, 102%-113%). Subsequently, DSBP has been used for 10 critically ill patients. The patients were treated without CT simulation, and the median time between patient check-in to the department and completion of radiation therapy was 28 minutes (range, 18-47 minutes.) CONCLUSIONS: This study demonstrates that it is possible to safely use DSBP for the treatment of critically ill patients. This method has the potential to simplify the treatment process and improve the speed and safety of treatment.


Asunto(s)
Enfermedad Crítica , Humanos , Radiometría , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador , Estudios Retrospectivos , Tomografía Computarizada por Rayos X
6.
Cells ; 9(1)2019 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-31906106

RESUMEN

Pancreatic cancer (PanCa) is one of the leading causes of death from cancer in the United States. The current standard treatment for pancreatic cancer is gemcitabine, but its success is poor due to the emergence of drug resistance. Natural products have been widely investigated as potential candidates in cancer therapies, and cucurbitacin D (Cuc D) has shown excellent anticancer properties in various models. However, there is no report on the therapeutic effect of Cuc D in PanCa. In the present study, we investigated the effects of the Cuc D on PanCa cells in vitro and in vivo. Cuc D inhibited the viability of PanCa cells in a dose and time dependent manner, as evident by MTS assays. Furthermore, Cuc D treatment suppressed the colony formation, arrest cell cycle, and decreased the invasion and migration of PanCa cells. Notably, our findings suggest that mucin 13 (MUC13) is down-regulated upon Cuc D treatment, as demonstrated by Western blot and qPCR analyses. Furthermore, we report that the treatment with Cuc D restores miR-145 expression in PanCa cells/tissues. Cuc D treatment suppresses the proliferation of gemcitabine resistant PanCa cells and inhibits RRM1/2 expression. Treatment with Cuc D effectively inhibited the growth of xenograft tumors. Taken together, Cuc D could be utilized as a novel therapeutic agents for the treatment/sensitization of PanCa.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Triterpenos/farmacología , Animales , Antineoplásicos Fitogénicos/administración & dosificación , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/farmacocinética , Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacología , Modelos Animales de Enfermedad , Resistencia a Antineoplásicos , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Ratones , Modelos Moleculares , Mucinas/genética , Mucinas/metabolismo , Neoplasias Pancreáticas , Relación Estructura-Actividad , Triterpenos/administración & dosificación , Triterpenos/química , Triterpenos/farmacocinética , Ensayos Antitumor por Modelo de Xenoinjerto , Gemcitabina
7.
Phys Med Biol ; 53(24): 7073-86, 2008 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-19015580

RESUMEN

The dosimetric impact of intrafraction prostate motion was investigated for helical tomotherapy treatments. Measured motion tracks were used to calculate the dosimetric impact on delivered target dose distributions. A dynamic dose calculation engine was developed to facilitate this evaluation. It was found that the D95% (minimum dose to 95% of the volume) changes in the prostate were well correlated with D95% changes in the PTV. This means that the dosimetric impact of intrafraction motion is not restricted to the periphery of the target. The amount of motion was not well correlated with the dosimetric impact (measured in target D95% changes) of motion. The relationship between motion and its dosimetric impact is complex and depends on the timing and direction of the movement. These findings have implications for motion management techniques. It appears that the use of target margins is not an effective strategy to protect the prostate from the effects of observed intrafraction motion. The complex relationship between motion and its dosimetric effect renders simple threshold-based intervention schemes inefficient. Monitoring of actual prostate motion would allow the documentation of the dosimetric impact and implementation of corrective action if needed. However, when motion management techniques are evaluated, it should be kept in mind that the dosimetric impact of observed prostate motion is small for the majority of fractions.


Asunto(s)
Neoplasias de la Próstata/radioterapia , Radiometría/métodos , Radioterapia de Intensidad Modulada/instrumentación , Relación Dosis-Respuesta en la Radiación , Humanos , Masculino , Modelos Teóricos , Movimiento (Física) , Movimiento , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia de Intensidad Modulada/métodos , Reproducibilidad de los Resultados , Factores de Tiempo
8.
Int J Radiat Oncol Biol Phys ; 65(1): 284-90, 2006 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-16618583

RESUMEN

PURPOSE: To evaluate two different techniques for whole-breast treatments delivered using the Hi-ART II tomotherapy device. METHODS AND MATERIALS: Tomotherapy uses the standard rotational helical delivery. Topotherapy uses a stationary gantry while delivering intensity-modulated treatments. CT scans from 5 breast cancer patients were used. The prescription dose was 50.4 Gy. RESULTS: On average, 99% of the target volume received 95% of prescribed dose with either technique. If treatment times are restricted to less than 9 min, the average percentage ipsilateral lung receiving > or =20 Gy was 22% for tomotherapy vs. 10% for topotherapy. The ipsilateral lung receiving > or =50.4 Gy was 4 cc for tomotherapy vs. 27 cc for topotherapy. The percentage of left ventricle receiving > or =30 Gy was 14% with tomotherapy vs. 4% for topotherapy. The average doses to the contralateral breast and lung were 0.6 and 0.8 Gy, respectively, for tomotherapy vs. 0.4 and 0.3 Gy for topotherapy. CONCLUSIONS: Tomotherapy provides improved target dose homogeneity and conformality over topotherapy. If delivery times are restricted, topotherapy reduces the amount of heart and ipsilateral lung volumes receiving low doses. For whole-breast treatments, topotherapy is an efficient technique that achieves adequate target uniformity while maintaining low doses to sensitive structures.


Asunto(s)
Neoplasias de la Mama/radioterapia , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia de Intensidad Modulada/métodos , Mama/efectos de la radiación , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/patología , Femenino , Humanos , Pulmón/efectos de la radiación , Traumatismos por Radiación/prevención & control , Dosificación Radioterapéutica , Factores de Tiempo , Tomografía Computarizada Espiral/métodos
9.
PLoS One ; 11(12): e0167353, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27936055

RESUMEN

Haiti endures the poorest water and sanitation infrastructure in the Western Hemisphere, where waterborne diseases cause significant morbidity and mortality. Most of these diseases are reported to be caused by waterborne pathogens. In this study, we examined the overall bacterial diversity of selected source and point-of-use water from rural areas in Central Plateau, Haiti using pyrosequencing of 16s rRNA genes. Taxonomic composition of water samples revealed an abundance of Firmicutes phyla, followed by Proteobacteria and Bacteroidetes. A total of 38 bacterial families and 60 genera were identified. The presence of several Klebsiella spp. (tentatively, K. pneumoniae, K. variicola and other Klebsiella spp.) was detected in most water samples. Several other human pathogens such as Aeromonas, Bacillus, Clostridium, and Yersinia constituted significantly higher proportion of bacterial communities in the point-of-use water samples compared to source water. Bacterial genera traditionally associated with biofilm formation, such as Chryseobacterium, Fusobacterium, Prevotella, Pseudomonas were found in the point-of-use waters obtained from water filters or domestic water storage containers. Although the pyrosequencing method utilized in this study did not reveal the viability status of these pathogens, the abundance of genetic footprints of the pathogens in water samples indicate the probable risk of bacterial transmission to humans. Therefore, the importance of appropriate handling, purification, and treatment of the source water needed to be clearly communicated to the communities in rural Haiti to ensure the water is safe for their daily use and intake.


Asunto(s)
Bacterias/aislamiento & purificación , Metagenómica , ARN Ribosómico 16S/aislamiento & purificación , Microbiología del Agua , Bacterias/clasificación , Bacterias/genética , Bacteroidetes/clasificación , Bacteroidetes/genética , Bacteroidetes/aislamiento & purificación , Biodiversidad , Firmicutes/clasificación , Firmicutes/genética , Firmicutes/aislamiento & purificación , Haití , Humanos , Proteobacteria/clasificación , Proteobacteria/genética , Proteobacteria/aislamiento & purificación , ARN Bacteriano/genética , ARN Bacteriano/aislamiento & purificación , ARN Ribosómico 16S/genética
10.
Int J Radiat Oncol Biol Phys ; 84(5): 1220-5, 2012 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-22483699

RESUMEN

PURPOSE: To determine the daily and cumulative dosimetric effects of intrafraction prostate motion on step-and-shoot (SNS) intensity-modulated radiation therapy (IMRT) plans, to evaluate the correlation of dosimetric effect with motion-based metrics, and to compare on a fraction-by-fraction basis the dosimetric effect induced in SNS and helical tomotherapy plans. METHODS AND MATERIALS: Intrafraction prostate motion data from 486 fractions and 15 patients were available. A motion-encoded dose calculation technique was used to determine the variation of the clinical target volume (CTV) D(95%) values with respect to the static plan for SNS plans. The motion data were analyzed separately, and the correlation coefficients between various motion-based metrics and the dosimetric effect were determined. The dosimetric impact was compared with that incurred during another IMRT technique to assess correlation across different delivery techniques. RESULTS: The mean (±1 standard deviation [SD]) change in D(95%) in the CTV over all 486 fractions was 0.2 ± 0.5%. After the delivery of five and 12 fractions, the mean (±1 SD) changes over the 15 patients in CTV D(95%) were 0.0 ± 0.2% and 0.1 ± 0.2%, respectively. The correlation coefficients between the CTV D(95%) changes and the evaluated motion metrics were, in general, poor and ranged from r = -0.2 to r = -0.39. Dosimetric effects introduced by identical motion in SNS and helical tomotherapy IMRT techniques were poorly correlated with a correlation coefficient of r = 0.32 for the CTV. CONCLUSIONS: The dosimetric impact of intrafraction prostate motion on the CTV is, in general, small. In only 4% of all fractions did the dosimetric consequence exceed 1% in the CTV. As expected, the cumulative effect was further reduced with fractionation. The poor correlations between the calculated motion parameters and the subsequent dosimetric effect implies that motion-based thresholds are of limited value in predicting the dosimetric impact of intrafraction motion. The dosimetric effects between the two evaluated delivery techniques were poorly correlated.


Asunto(s)
Fraccionamiento de la Dosis de Radiación , Movimiento , Neoplasias de la Próstata/radioterapia , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia de Intensidad Modulada/métodos , Humanos , Masculino , Movimiento (Física) , Aceleradores de Partículas , Próstata , Radioterapia de Intensidad Modulada/instrumentación
11.
Int J Radiat Oncol Biol Phys ; 74(4): 1134-42, 2009 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-19231105

RESUMEN

PURPOSE: To assess the dosimetric consequence of intrafraction prostate motion on helical tomotherapy plans. METHODS AND MATERIALS: An electromagnetic tracking device was used to measure real-time prostate motion for 515 fractions (16 patients). Motion tracks were used to retrospectively recalculate dose distributions using a four-dimensional calculation engine. The minimum dose (D(min)), maximum dose (D(max)), and dose to 95% of the volume (D(95%)) were calculated for target volumes and compared with respective values from the treatment plan. The dosimetric effect was evaluated for each fraction. For each patient, the running cumulative effect was assessed throughout the course of treatment. Calculations were repeated assuming a time delay between initial patient setup and start of treatment. RESULTS: Averaged over all fractions, the mean change in target D(95%) was <1% (SD, 3-4%). Reductions in target D(95%) of up to 20% were seen in individual fractions. Changes in prostate D(95%) were similar in frequency and magnitude to D(95%) changes in the planning target volume. The cumulative effect on target D(95%) was approximately 1% (SD, 1%). The average cumulative effect after five fractions was 1% (SD, 1.5%). CONCLUSIONS: In general, the dosimetric effect of observed prostate motion on target D(95%)was small. Infrequently severe D(95%) degradations were observed for individual fractions, but their effect on the cumulative dose distribution was quickly reduced with minimal fractionation.


Asunto(s)
Movimiento , Próstata , Neoplasias de la Próstata/radioterapia , Radioterapia Conformacional , Fraccionamiento de la Dosis de Radiación , Campos Electromagnéticos , Humanos , Masculino , Modelos Estadísticos , Próstata/diagnóstico por imagen , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Prótesis e Implantes , Radiografía , Recto/diagnóstico por imagen , Vesículas Seminales , Vejiga Urinaria/diagnóstico por imagen
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