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1.
Artículo en Inglés | MEDLINE | ID: mdl-37847234

RESUMEN

Background: The efficacy of cannabis treatment is determined by the active pharmaceutical ingredients (APIs) of the ingested composition. Despite smoking predominancy in cannabis treatment, very little is known regarding its yield and provision rate of cannabis APIs. Material and Methods: Ten experiments were performed, studying changes in APIs content during smoking, using a designated smoking machine. APIs content was evaluated via analysis of a cigarette's residuals and of the smoke composition; cannabinoid and terpene content were assessed. Results: Results demonstrated increased cannabinoid content in the cigarette sections closer to the mouth, as compared with those closer to the lit end. Similarly, cannabinoid content in the inhaled smoke increases as smoking progresses. Similar results are found for sesquiterpenes. Monoterpenes, having lower boiling points reach the smoke before the sesquiterpenes and cannabinoids do. Conclusion: A mechanism is proposed, including: (i) decarboxylation and evaporation of APIs adjacent to the lit end, (ii) transition of API vapors away from the hot zone, (iii) condensation of APIs in cigarette's sections closer to the mouth, and (iv) re-evaporation of APIs as the hot zone approaches, thereby reaching the smoke. Differences in the boiling points between the various APIs result in varying composition along the cigarette and in the inhaled smoke. The main implications are: (i) APIs delivery through smoking cannot be uniform, (ii) APIs amount per puff increases as smoking progresses, and (iii) terpenes are inhaled before the cannabinoids are. Thus, in addition to its known health-threatening hazards, smoking entails nonuniform provision of APIs, even within the same cigarette.

2.
Cannabis Cannabinoid Res ; 8(3): 414-425, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-35442765

RESUMEN

Medical cannabis products contain dozens of active pharmaceutical ingredients (APIs) derived from the cannabis plant. However, their actual compositions and relative doses significantly change according to the production methods. Product compositions are strongly dependent on processing step conditions and on components' evaporation during those steps. Review of the documentation presented to caregivers and to patients show erroneous data or misinterpretation of data related to the evaporation, for example, cannabinoids' boiling points, as well as confusions between terms, such as boiling, vaporization, and evaporation. Clarifying these aspects is essential for caregivers, for researchers, and for developers of manufacturing processes. Original and literature data were analyzed, comparing composition changes during various processing steps and correlating the extent of change to components' vapor pressures at the corresponding temperature. Evaporation-related composition changes start at temperatures as low as those of drying and curing and become extensive during decarboxylation. The relative rate of components' evaporation is determined by their relative vapor pressure and monoterpenes are lost first. On vaping, terpenes are inhaled before cannabinoids do. Commercial medical cannabis products are deficient in terpenes, mainly monoterpenes, compared with the cannabis plants used to produce them. Terms, such as "whole plant" and "full spectrum," are misleading since no product actually reflects the original cannabis plant composition. There are important implications for medical cannabis manufacturing and for the ability to make the most out of the terpene API contribution. Medical cannabis products' composition and product delivery are controlled by the relative vapor pressure of the various APIs. Quantitative data provided in this study can be used for improvement to reach better accuracy, reproducibility, and preferred medical cannabis compositions.


Asunto(s)
Cannabinoides , Cannabis , Marihuana Medicinal , Vapeo , Humanos , Marihuana Medicinal/uso terapéutico , Presión de Vapor , Preparaciones Farmacéuticas , Reproducibilidad de los Resultados , Terpenos , Monoterpenos
3.
Front Pharmacol ; 13: 979403, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36386202

RESUMEN

Cannabidiol (CBD) rich products are successfully used in some countries for treating symptoms associated with autism spectrum disorder (ASD). Yet, CBD provides insufficient intervention in some individuals, or for some characterizing symptoms of ASD, raising the need for improved compositions. The current study presents a case wherein pure CBD was sufficient for treating ASD during childhood and early adolescence. However, it became insufficient during puberty accompanied by increased hyperactivity, agitation, and frequent severe aggressive behavior. Increasing the CBD dose did not result in significant improvement. Enriching the pure CBD with a carefully selected blend of anxiolytic and calming terpenes, resulted in gradual elimination of those aggressive events. Importantly, this was achieved with a significantly reduced CBD dose, being less than one-half the amount used when treating with pure CBD. This case demonstrates a strong improvement in efficacy due to terpene enrichment, where pure CBD was not sufficient. Combined with terpenes' high safety index and the ease with which they can be incorporated into cannabinoid-containing products, terpene-enriched CBD products may provide a preferred approach for treating ASD and related conditions. The careful selection of terpenes to be added enables maximizing the efficacy and tailoring the composition to particular and changing needs of ASD subjects, e.g., at different times of the day (daytime vs nighttime products).

4.
Molecules ; 27(20)2022 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-36296511

RESUMEN

Differences between therapeutic effects of medical cannabis inflorescences and those of their extracts are generally attributed to the differences in administration form and in the resultant pharmacokinetics. We hypothesized that difference may further extend to the composition of the actually consumed drug. Cannabinoid and terpene contents were compared between commercial cannabis inflorescences (n = 19) and decarboxylated extracts (n = 12), and between inflorescences and decarboxylated extracts produced from them (n = 10). While cannabinoid content was preserved in the extracts, a significant loss of terpenes was evident, mainly in the more volatile monoterpenes and monoterpenoids (representing a loss of about 90%). This loss changes the total terpene content, the proportion of monoterpenes out of the total terpenes, and the monoterpene/cannabinoid ratio. Terpene deficiency might impair extracts' pharmacological efficacy and might contribute to the patients' preference to inflorescences-smoking. This argues against the validity of terms such as "whole plant" and "full spectrum" extracts and creates a misleading assumption that extracts represent the pharmacological profile of the sourced inflorescences. Furthermore, it reduces the diversity in extracts, such as loss of differences between sativa-type and indica-type. Enriching cannabis extracts with selected terpenes may provide a suitable solution, generating a safe, precise, and reproducible drug with tailored cannabinoid and terpene contents. Careful selection of terpenes to be added enables tailor-made extracts, adjusted for various medicinal aims and for different populations.


Asunto(s)
Cannabinoides , Cannabis , Alucinógenos , Marihuana Medicinal , Humanos , Terpenos , Monoterpenos , Agonistas de Receptores de Cannabinoides , Extractos Vegetales
5.
Adv Radiat Oncol ; 6(6): 100815, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34934866

RESUMEN

PURPOSE: To analyze clinical toxicity and quality-of-life (QOL) outcomes among patients with stage I non-small cell lung cancer (NSCLC) after stereotactic body radiation therapy (SBRT) as a function of radiation dose and volume parameters. METHODS AND MATERIALS: In this institutional review board-approved study, 55 patients with stage I NSCLC who received SBRT (12 Gy × 4) and completed QOL forms were analyzed. Clinical symptoms and QOL outcomes were measured at baseline and at 3, 6, 12, 18, 24, and 36 months after SBRT. Clinical toxicity was graded using the Common Terminology Criteria for Adverse Events, version 4.0. Quality of life was followed using the validated Functional Assessment of Cancer Therapy-Lung-Trial Outcome Index (FACT-L-TOI) instrument. Dosimetric parameters including the mean lung radiation dose and the volume of normal lung receiving greater than 5, 10, 13, or 20 Gy (V5, V10, V13, and V20) were measured from the radiation treatment plan. Student t tests and Pearson correlation analyses were used to examine the relationships between radiation lung metrics and clinically meaningful changes in QOL and/or clinical toxic effects. The Kaplan-Meier method was used to estimate rates of local control (LC), disease-free survival (DFS), and overall survival (OS). RESULTS: With a median follow-up of 24 months, the 3-year LC, DFS, and OS were 93%, 65%, and 84%, respectively, with a 5.5% rate of grade-3 toxic effects and no grade 4 or 5 toxic effects. Clinically meaningful declines in patient-reported QOL (FACT-L-TOI, lung cancer subscale, physical well-being, and/or functional well-being) posttreatment significantly correlated with increased dosimetric parameters such as V10, V13, and V20. CONCLUSION: Although lung SBRT was associated with excellent LC and minimal clinical toxic effects for early-stage NSCLC, clinically meaningful declines in QOL were significantly correlated with increasing lung dose and volume parameters.

6.
JAMA Surg ; 156(10): 988-989, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-34132761

Asunto(s)
Cannabis , Analgésicos , Humanos
7.
Cureus ; 12(11): e11477, 2020 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-33329973

RESUMEN

World Health Organization (WHO) grade I meningiomas are slow-growing and typically benign brain tumors that can often be easily removed by surgery and rarely become malignant. We report the case of a WHO grade I meningioma in a 67-year-old man with multiple extracranial metastases.

8.
Curr Opin Anaesthesiol ; 33(6): 832-840, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33093301

RESUMEN

PURPOSE OF REVIEW: Growing numbers of patients, consuming cannabinoids admitted to surgery, create a challenge to anesthesia providers. This review provides a summary of recent literature related to cannabis and anesthesia, with specific recommendations to the anesthetic management of medical cannabis consumers. RECENT FINDINGS: At present, cannabis has found its way to public consensus in many countries and is penetrating slower to different medical fields. We relate and discuss recent findings investigating effects of cannabis consumption on the various aspects including perioperative measures, post-operative pain, PONV, cardiovascular stability, and anesthesia monitoring. SUMMARY: Recent surveys estimate that 10-20% of adult populations have consumed cannabis in the past year. Medical cannabis consumers are a newer group of cannabis users. Anesthesia providers have to update their knowledge on cannabis and possible anesthetic interaction. It is unreasonable to make recommendations that apply to the whole heterogeneous group of cannabis users, but is easier with the more homogenous group of Medical cannabis users, characterized by frequent use and relatively high cannabis doses, combined with good knowledge of administered composition and protocol, as well as adverse and withdrawal effects. Anesthesia providers have to know the effects and modify anesthetic plan accordingly. We provide perioperative anesthetic recommendations related to medical cannabis consumers. Collecting information of the effects of medical cannabis use in perioperative setting will further create a highly useful database for anesthetics in the close future.


Asunto(s)
Anestésicos , Cannabinoides/uso terapéutico , Cannabis/efectos adversos , Marihuana Medicinal/uso terapéutico , Adulto , Analgésicos , Anestésicos/administración & dosificación , Anestésicos/efectos adversos , Cannabinoides/efectos adversos , Humanos , Marihuana Medicinal/efectos adversos
9.
Med Phys ; 47(9): 4077-4086, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32449176

RESUMEN

PURPOSE: Deep learning models have had a great success in disease classifications using large data pools of skin cancer images or lung X-rays. However, data scarcity has been the roadblock of applying deep learning models directly on prostate multiparametric MRI (mpMRI). Although model interpretation has been heavily studied for natural images for the past few years, there has been a lack of interpretation of deep learning models trained on medical images. In this paper, an efficient convolutional neural network (CNN) was developed and the model interpretation at various convolutional layers was systematically analyzed to improve the understanding of how CNN interprets multimodality medical images and the predictive powers of features at each layer. The problem of small sample size was addressed by feeding the intermediate features into a traditional classification algorithm known as weighted extreme learning machine (wELM), with imbalanced distribution among output categories taken into consideration. METHODS: The training data collection used a retrospective set of prostate MR studies, from SPIE-AAPM-NCI PROSTATEx Challenges held in 2017. Three hundred twenty biopsy samples of lesions from 201 prostate cancer patients were diagnosed and identified as clinically significant (malignant) or not significant (benign). All studies included T2-weighted (T2W), proton density-weighted (PD-W), dynamic contrast enhanced (DCE) and diffusion-weighted (DW) imaging. After registration and lesion-based normalization, a CNN with four convolutional layers were developed and trained on tenfold cross validation. The features from intermediate layers were then extracted as input to wELM to test the discriminative power of each individual layer. The best performing model from the tenfolds was chosen to be tested on the holdout cohort from two sources. Feature maps after each convolutional layer were then visualized to monitor the trend, as the layer propagated. Scatter plotting was used to visualize the transformation of data distribution. Finally, a class activation map was generated to highlight the region of interest based on the model perspective. RESULTS: Experimental trials indicated that the best input for CNN was a modality combination of T2W, apparent diffusion coefficient (ADC) and DWIb50 . The convolutional features from CNN paired with a weighted extreme learning classifier showed substantial performance compared to a CNN end-to-end training model. The feature map visualization reveals similar findings on natural images where lower layers tend to learn lower level features such as edges, intensity changes, etc, while higher layers learn more abstract and task-related concept such as the lesion region. The generated saliency map revealed that the model was able to focus on the region of interest where the lesion resided and filter out background information, including prostate boundary, rectum, etc. CONCLUSIONS: This work designs a customized workflow for the small and imbalanced dataset of prostate mpMRI where features were extracted from a deep learning model and then analyzed by a traditional machine learning classifier. In addition, this work contributes to revealing how deep learning models interpret mpMRI for prostate cancer patient stratification.


Asunto(s)
Imágenes de Resonancia Magnética Multiparamétrica , Imagen de Difusión por Resonancia Magnética , Humanos , Masculino , Redes Neurales de la Computación , Próstata/diagnóstico por imagen , Estudios Retrospectivos
10.
Cureus ; 11(9): e5774, 2019 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-31723533

RESUMEN

Background Stereotactic body radiation therapy (SBRT) is a proven and effective modality for treatment of hepatic primary and metastatic tumors. However, these lesions are challenging for planning and treatment execution due to natural anatomic changes associated with respiration. Magnetic resonance imaging (MRI) offers superior soft tissue contrast resolution and the ability for real-time image-guided treatment delivery and lesion tracking. Objective To evaluate the plan quality, treatment delivery, and tumor response of a set of liver SBRT cancer treatments delivered with magnetic resonance (MR)-guided radiotherapy on a MR-linear accelerator (MR-linac). Methods Treatment data from 29 consecutive patients treated with SBRT were reviewed. All treatments were performed using a step and shoot technique to one or more liver lesions on an MR-linac platform. Patients received 45 to 50 Gy prescribed to at least 95% of the planning target volume (PTV) in five fractions except for two patients who received 27-30 Gy in three fractions. Computed tomography and MRI simulation were performed in the supine position prior to treatment in the free-breathing, end exhalation, and end inhalation breath-hold positions to determine patient tolerability and potential dosimetric advantages of each technique. Immobilization consisted of using anterior and posterior torso MRI receive coils embedded in a medium-sized vacuum cushion. Gating was performed using sagittal cine images acquired at 4 frames/second. Gating boundaries were defined in the three major axes to be 0.3 to 0.5 cm. An overlapping region of interest, defined as the percentage volume allowed outside the boundary for beam-on to occur, was set between 1 and 10%. The contoured target was assigned a 5-mm PTV expansion. Organs at risk constraints adopted by the American Association of Physicists in Medicine Task Group 101 were used during optimization. Results Twenty-nine patients, with a total of 34 lesions, successfully completed the prescribed treatment with minimal treatment breaks or delays. Twenty-one patients were treated at end-exhale, and six were treated at end-inhale. Two patients were treated using a free-breathing technique due to poor compliance with breath-hold instructions. The reported mean liver dose was 5.56 Gy (1.39 - 10.43; STD 2.85) and the reported mean liver volume receiving the prescribed threshold dose was 103.1 cm3 (2.9 - 236.6; STD 75.2). Follow-up imaging at one to 12 months post treatment confirmed either stable or decreased size of treated lesions in all but one patient. Toxicities were mild and included nausea/vomiting, abdominal pain and one case of bloody diarrhea. Four patients died due to complications from liver cirrhosis unrelated to radiation effect. Conclusion SBRT treatment using a gated technique on an MR-linac has been successfully demonstrated. Potential benefits of this modality include decreased liver dose leading to decreased toxicities. Further studies to identify the benefits and risks associated with MR-guided SBRT are necessary.

11.
J Obstet Gynaecol ; 37(1): 5-10, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27760483

RESUMEN

In contrast to multiple myeloma (MM) which exhibits diffuse bone marrow and other organ involvement, solitary plasmacytomas carry a favourable prognosis. Extramedullary plasmacytomas (EMP) are a unique form of plasma cell neoplasms. These tumours are rare in the female reproductive tract. Only 24 cases of gynaecologic plasmacytomas were reported to date (7 cases were solitary plasmacytomas and 17 cases were either part of disseminated MM with involvement of a gynaecologic organ or were lacking complete work-up to rule out MM). The standard care of gynaecologic solitary EMP is surgical resection alone when feasible. Adjuvant radiation therapy may be considered for adverse prognostic factors such as positive resection margins. MM with gynaecologic organ involvement should be managed with systemic therapy and defer local therapies to symptomatic progression.


Asunto(s)
Neoplasias de los Genitales Femeninos/terapia , Mieloma Múltiple/terapia , Plasmacitoma/terapia , Femenino , Humanos
12.
Anticancer Res ; 15(5B): 2071-6, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8572604

RESUMEN

The effect of various tyrosine protein kinase inhibitors on processes involved in the antiproliferative effect of interferon-gamma on WISH cells was studied. Following 24 hr treatment interferon-gamma inhibited thymidine incorporation into DNA and thymidine kinase activity, but no significant effect on cell number was observed. The isoflavonoid, genistein, which is a specific inhibitor of tyrosine protein kinase, reversed the inhibition in thymidine incorporation caused by the cytokine in a dose dependent manner. Prunetin, a member of the same group, did not significantly antagonize this effect. N alpha-tosyl-L-lysyl-chloromethane, a serine protease inhibitor which also serves as a tyrosine protein kinase inhibitor, partially reversed the effect of interferon-gamma at a concentration of 100 microM. The bioflavonoid, quercetin, a non-specific tyrosine protein kinase inhibitor, at a concentration of 30 microM completely abolished the action of interferon-gamma on thymidine incorporation. Genistein completely reversed the inhibition of thymidine kinase exerted by interferon, while quercetin had only a slight effect. However, the drugs could not antagonize the antiproliferative effect of interferon following 48 hr incubation, as measured by reduction of cell number. The results indicate that tyrosine protein kinase may play a role in the effects of interferon on thymidine metabolism and thymidine kinase activity. The differential effects of the inhibitors on thymidine metabolism and cell proliferation could support dissociation between the effect of interferon-gamma on these processes. Alternatively, this dissociation of effects could point to the limited use of inhibitors in clarifying modes of action as described.


Asunto(s)
Interferón gamma/farmacología , Proteínas Tirosina Quinasas/antagonistas & inhibidores , División Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Genisteína , Isoflavonas/farmacología , Proteínas Tirosina Quinasas/fisiología , Quercetina/farmacología , Timidina/metabolismo
13.
Transfusion ; 32(3): 210-4, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1557800

RESUMEN

The present study describes the use of a new polyacrolein microsphere (acrobead) protein A column. This method enables immunomodulation by the perfusion of whole blood. The efficacy of the column and its adverse effects following perfusion of blood of patients with immune thrombocytopenic purpura (ITP) or malignancies were investigated. Concurrent experiments in which blood was perfused through an acrobead lactoglobulin column were carried out. Cellular blood components were mildly affected during the procedure. A moderate decrease in platelet number, to a nadir of 90 x 10(3) per microL (90 x 10(9)/L), was documented. During the hemoperfusion of ITP patients' blood, plasma hemoglobin reached levels of 25 to 40 mg per dL, a level similar to that found in banked blood during storage. Plasma tumor necrosis factor level, which serves as an indicator of monocytic activation, increased after 90 minutes of hemoperfusion. IgG and immune complexes were removed. The specific activities (removal of mg Ig/mL bead) of acrobead protein A columns, using blood from patients with ITP or malignancies, were 4.9 and 4.5 mg IgG per mL of bead, respectively. The diminution of platelet-specific IgG in the plasma of patients with ITP was documented as well. There was no activation of the fibrinolytic system as examined by D-dimers. The use of this new technique, which incorporates the method of direct hemoperfusion, is suggested for future clinical studies.


Asunto(s)
Hemoperfusión/métodos , Complejo Antígeno-Anticuerpo/sangre , Cromatografía/métodos , Estudios de Evaluación como Asunto , Humanos , Microesferas , Neoplasias/sangre , Púrpura Trombocitopénica Idiopática/sangre , Proteína Estafilocócica A
14.
J Clin Ultrasound ; 9(1): 11-5, 1981 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-6792224

RESUMEN

Five cases of gastrointestinal leiomyosarcoma were studied by ultrasound. Sonographic features of a huge mass with a thick echogenic rim and central sonolucent cavitation were seen in four cases with presenting symptoms of an abdominal mass. In a fifth case necrotic metastasis was seen in the liver after removal of a leiomyosarcoma. Although not pathognomonic, such features should strongly suggest the diagnosis of leiomyosarcoma.


Asunto(s)
Neoplasias Gastrointestinales/diagnóstico , Leiomiosarcoma/diagnóstico , Ultrasonografía , Anciano , Neoplasias Duodenales/diagnóstico , Neoplasias Duodenales/cirugía , Femenino , Humanos , Leiomiosarcoma/cirugía , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/cirugía , Masculino , Persona de Mediana Edad , Neoplasias del Recto/complicaciones , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/cirugía
15.
Acta Endocrinol (Copenh) ; 93(4): 475-8, 1980 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6247868

RESUMEN

Cyclic AMP levels in liver slices of hamsters exposed to 35 degrees C for 21 days and controls maintained at 22 degrees C was found to be similar in basal conditions. Glucagon (10 microgram/ml) caused 3.5 times elevation of cyclic AMP levels in control hamsters and 9 times elevation in 35 degrees C exposed hamsters, thus a difference of 150% of the nucleotide concentration was found between the two experimental groups. When 10(-2)M theophylline was added, the cyclic AMP levels were 80% higher in 35 degrees C exposed hamsters both in the presence and absence of 10 microgram/ml glucagon. The difference between controls and heat exposed animals was found to be the same when various concentrations of both glucagon or prostaglandin E1 were added to the liver slices. Adenylate cyclase activity was similar in both experimental groups, while low Km phosphodiesterase was significantly less active in the liver of 35 degrees C exposed animals when compared to the controls.


Asunto(s)
AMP Cíclico/metabolismo , Glucagón/farmacología , Hígado/metabolismo , Prostaglandinas E/farmacología , Adenilil Ciclasas/metabolismo , Animales , Cricetinae , Calor , Técnicas In Vitro , Hígado/efectos de los fármacos , Masculino , Mesocricetus , Hidrolasas Diéster Fosfóricas/metabolismo , Teofilina/farmacología
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