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1.
Int J Pharm ; 661: 124357, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38897490

RESUMO

When tablets are manufactured on a rotary tablet press and the throughput is increased, it leads to changes in powder dynamics during die filling due to formulation characteristics and changing powder flow in the feed frame. This may result, a.o. in increased tablet weight variability, poorer content uniformity, capping and lamination. This research focuses on explaining the die filling performance depending on material properties and process settings, including throughput for small and large tablets. It was concluded that throughput had a negative impact on die filling variability, which is related to reduced residence time and lower fill fraction of the feed frame and dies. Furthermore, the die filling mechanism was inherently different for large tablets in comparison to small tablets. Higher die filling consistency was observed for dense, less porous, less compressible and better flowing powders. As a result of this work, a model was developed to predict the impact of formulation properties and process settings on die filling variability and its dependency on changes in throughput. This model will benefit formulation development at an early stage when active ingredient availability may be challenging as it will avoid the need to conduct experiments at high throughputs.

2.
Int J Pharm ; 631: 122534, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36563797

RESUMO

The importance of residence time distribution modeling is acknowledged as a tool for enabling material tracking and control within a continuous manufacturing line in order to safeguard both product quality and production efficiency. One of the first unit-operations into a continuous direct compression line (i.e. CDC-line) worthwhile doing extensive RTD-analysis upon are the LIW-feeders since they dose the ingredients in a controlled way following the label claim and hence can directly influence critical quality attributes like content uniformity. An NIR measurement method was developed determining the RTD of selected powders at specific feeder settings. Step-change experiments using sodium saccharin as a tracer were conducted. In order to gain and in depth understanding of the material flow, spatial samples throughout the hopper were taken at predefined timepoints during the step change experiments. This revealed the presence of a bypass trajectory along the edges of the agitator, while in the center of the agitator an inner mixing volume in which the tracer concentration lags behind seemed to be present. Finally, a model based on a plug flow and continuous stirred tank reactor was evaluated. The fitted model was not able to capture this complex flow behavior and shows the need for an extended compartmental model distinguishing between a bypass trajectory formed by the agitator and an inner mixing volume.


Assuntos
Química Farmacêutica , Tecnologia Farmacêutica , Tecnologia Farmacêutica/métodos , Química Farmacêutica/métodos , Pós , Veículos Farmacêuticos , Pressão
3.
Curr Oncol ; 26(4): e541-e550, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31548823

RESUMO

Background: For patients who are diagnosed with early-stage cutaneous melanoma, the principal therapy is wide surgical excision of the primary tumour and assessment of lymph nodes. The purpose of the present guideline was to update the 2010 Cancer Care Ontario guideline on wide local excision margins and sentinel lymph node biopsy (slnb), including treatment of the positive sentinel node, for melanomas of the trunk, extremities, and head and neck. Methods: Using Ovid, the medline and embase electronic databases were systematically searched for systematic reviews and primary literature evaluating narrow compared with wide excision margins and the use of slnb for melanoma of the truck and extremities and of the head and neck. Search timelines ran from 2010 through week 25 of 2017. Results: Four systematic reviews were chosen for inclusion in the evidence base. Where systematic reviews were available, the search of the primary literature was conducted starting from the end date of the search in the reviews. Where systematic reviews were absent, the search for primary literature ran from 2010 forward. Of 1213 primary studies identified, 8 met the inclusion criteria. Two randomized controlled trials were used to inform the recommendation on completion lymph node dissection.Key updated recommendations include:■ Wide local excision margins should be 2 cm for melanomas of the trunk, extremities, and head and neck that exceed 2 mm in depth.■ slnb should be offered to patients with melanomas of the trunk, extremities, and head and neck that exceed 0.8 mm in depth.■ Patients with sentinel node metastasis should be considered for nodal observation with ultrasonography rather than for completion lymph node dissection. Conclusions: Recommendations for primary excision margins, sentinel lymph node biopsy, and completion lymph node dissection in patients with cutaneous melanoma have been updated based on the current literature.


Assuntos
Excisão de Linfonodo/métodos , Metástase Linfática/patologia , Melanoma/cirurgia , Neoplasias Cutâneas/cirurgia , Intervalo Livre de Doença , Medicina Baseada em Evidências , Humanos , Margens de Excisão , Melanoma/patologia , Ontário , Guias de Prática Clínica como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Biópsia de Linfonodo Sentinela , Neoplasias Cutâneas/patologia , Revisões Sistemáticas como Assunto , Resultado do Tratamento , Melanoma Maligno Cutâneo
4.
Curr Oncol ; 24(5): e403-e422, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29089811

RESUMO

BACKGROUND: This clinical practice guideline was developed to determine the level of evidence supporting the clinical utility of commercially available multigene profiling assays and to provide guidance about whether certain breast cancer patient populations in Ontario would benefit from alternative tests in addition to Oncotype dx (Genomic Health, Redwood City, CA, U.S.A.). METHODS: A systematic electronic Ovid search of the medline and embase databases sought out systematic reviews and primary literature. A systematic review and practice guideline was written by a working group and was then reviewed and approved by Cancer Care Ontario's Molecular Oncology Advisory Committee. RESULTS: Twenty-four studies assessing the clinical utility of Oncotype dx, Prosigna (NanoString Technologies, Seattle, WA, U.S.A.), EndoPredict (Myriad Genetics, Salt Lake City, U.S.A.), and MammaPrint (Agendia, Irvine, CA, U.S.A.) were included in the evidence base. CONCLUSIONS: The clinical utility of multigene profiling assays is currently established for an appropriate subset of patients with estrogen receptor-positive, her2-negative, node-negative breast cancer for whom a decision to give chemotherapy is difficult to make. For patients with estrogen receptor-positive tumours who receive tamoxifen alone, Oncotype dx, Prosigna, and EndoPredict validly identify a low-risk population with favourable outcomes, indicating that a low-risk assay result is actionable and the decision to withhold chemotherapy is supported. Clinical evidence indicates that a high Oncotype dx recurrence score can predict for chemotherapy benefit, but a high Prosigna or EndoPredict score, although prognostic, is not, based on clinical trial evidence, directly actionable. Prosigna and EndoPredict are statistically more likely to identify a population at risk for recurrence beyond 5 years, but that information is currently not actionable because of a lack of interventional studies.

5.
Clin Oncol (R Coll Radiol) ; 29(11): 711-717, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28928084

RESUMO

AIMS: This clinical practice guideline was developed to provide evidence-based guidance on the frequency by which prostate-specific antigen (PSA) levels should be tested in men after curative-intent treatment for prostate cancer and to define the most appropriate diagnostic testing if biochemical recurrence occurs. MATERIALS AND METHODS: An electronic search using OVID was used to systematically search the MEDLINE and EMBASE databases for systematic reviews and primary literature. A systematic review and practice guideline was written, reviewed and approved by the Guideline Development Group (GDG) and Program in Evidence-Based Care Report Approval Panel. External review by three prostate experts was completed, as well as an online consultation with healthcare professionals who were intended users of the guideline. RESULTS: Three systematic reviews and seven primary studies were included in the evidence base. All identified literature reported on diagnostic imaging properties of diagnostic tests following biochemical recurrence. CONCLUSIONS: Due to a lack of empirical research, few evidenced-based recommendations could be made with respect to a follow-up schedule of PSA testing for prostate cancer survivors following curative-intent treatment, or detailing diagnostic testing upon detection of biochemical recurrence. Accordingly, the GDG focused substantial effort on critical examination of the identified evidence, existing clinical practice guidelines and on obtaining clinical expertise consensus using a modified Delphi method. Overall, the recommendations embedded in this guideline reflect the best practice to date for the efficient and effective clinical follow-up care of prostate cancer survivors.


Assuntos
Assistência ao Convalescente/métodos , Prática Clínica Baseada em Evidências/métodos , Neoplasias da Próstata/terapia , Guias como Assunto , Humanos , Masculino , Neoplasias da Próstata/mortalidade , Sobreviventes
6.
Facts Views Vis Obgyn ; 9(4): 189-193, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30250652

RESUMO

OBJECTIVE: This study aims to identify geographical disparities in perinatal mortality and morbidity in the province of Antwerp, Belgium. We performed a retrospective cohort study from an existing database. Data included from 1 January , 2000 to 31 December, 2009 and including all deliveries in the Province of Antwerp, Belgium. Collected outcome measures : fetal death, early and late neonatal death, preterm birth, low birth weight. Outcomes were analyzed according to postal code of the pregnant women's address. RESULTS: A total of 167.246 deliveries in sixty postal codes were analyzed and statistically significant differences (p<0.001) between postal codes for all outcome measures except for early and late neonatal death were detected. Generally postal codes tend to have either high or low prevalences for all perinatal outcomes and two postal code zones had a significantly worse perinatal outcome on all fields. Major differences in perinatal outcome exist within the well-defined area of the relatively small province of Antwerp, Belgium. CONCLUSION: Perinatal outcome is strongly influenced by maternal postal code even within a relatively affluent European region demonstrating persistent health inequalities and suggesting further research is necessary to explain these differences and create interventions to diminish inequalities.

7.
J Steroid Biochem Mol Biol ; 100(4-5): 129-40, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16806904

RESUMO

Recent evidence indicates that progesterone metabolites play important roles in regulating breast cancer. Previous studies have shown that breast carcinoma and tumorigenic breast cell lines have higher 5alpha-reductase and lower 3alpha-hydroxysteroid oxidoreductase (3alpha-HSO) and 20alpha-HSO activities and mRNA expression levels than normal tissue and non-tumorigenic cell lines. The 5alpha-reduced progesterone metabolites such as 5alpha-dihydroprogesterone (5alphaP) promote both mitogenic and metastatic activity in breast cell lines in culture, whereas the 4-pregnene metabolites, 4-pregnen-3alpha-ol-20-one (3alphaHP) and 4-pregnen-20alpha-ol-3-one (20alphaHP) have the opposite (anti-cancer-like) effects. The 5alpha-reductase inhibitor dutasteride has been shown to inhibit 5alpha-reduction of testosterone to 5alpha-dihydrotestosterone in prostate tissue, resulting in decreased prostate volume. The aim of this study was to determine if dutasteride is an effective inhibitor of progesterone 5alpha-reduction in human breast cell lines and if such inhibition reduces mammary cell proliferation and detachment. The effect of dutasteride on progesterone metabolizing enzyme activities and mRNA expression were examined in tumorigenic MCF-7 and non-tumorigenic MCF-10A human breast cell lines. Dutasteride (10(-6)M) inhibited progesterone conversion to 5alpha-pregnanes by >95% and increased 4-pregnene production. The results indicated that effects of dutasteride on the progesterone metabolizing enzymes are due to direct inhibition of 5alpha-reductase activity and to altered levels of expression of 5alpha-reductase and HSO mRNAs. Treatment of cells with progesterone without medium change for 72 h resulted in significant conversion to 5alpha-pregnanes and increases in cell proliferation and detachment. The increases in proliferation and detachment were blocked by dutasteride and were reinstated by concomitant treatment with 5alphaP, providing proof-of-principle that the effects were due not to progesterone but to the 5alpha-reduced metabolites. This study provides the first evidence that dutasteride is a potent progesterone 5alpha-reductase inhibitor and that such inhibition may be beneficial in breast cancer.


Assuntos
3-Oxo-5-alfa-Esteroide 4-Desidrogenase/metabolismo , Azasteroides/metabolismo , Mama/citologia , Adesão Celular/fisiologia , Proliferação de Células , Inibidores Enzimáticos/metabolismo , Progesterona/metabolismo , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/genética , Inibidores de 5-alfa Redutase , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular , Dutasterida , Feminino , Humanos , Estrutura Molecular , Oxirredutases/genética , Oxirredutases/metabolismo , Pregnanos/química , Pregnanos/metabolismo , Pregnenos/metabolismo , RNA Mensageiro/metabolismo
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