Use of Computational Fluid Dynamics for improving freeze-dryers design and understanding. Part 1: Modelling the lyophilisation chamber

This manuscript shows how computational models, mainly based on Computational Fluid Dynamics (CFD), can be used to simulate different parts of an industrial freeze-drying equipment and to properly design them; in particular, the freeze-dryer chamber and the duct connecting the chamber with the condenser, with the valves and vanes eventually present are analysed in this work. In Part 1, it will be shown how CFD can be employed to improve specific designs, to perform geometry optimization, to evaluate different design choices and how it is useful to evaluate the effect on product drying and batch variance. Such an approach allows an in-depth process understanding and assessment of the critical aspects of lyophilisation. This can be done by running either steady-state or transient simulations with imposed sublimation rates or with multi-scale approaches. This methodology will be demonstrated on freeze-drying equipment of different sizes, investigating the influence of the equipment geometry and shelf inter-distance. The effect of valve type (butterfly and mushroom) and shape on duct conductance and critical flow conditions will be instead investigated in Part 2

Identification of calcium sensing receptor (CaSR) mRNA-expressing cells in normal and injured rat brain

Calcium sensing receptor (CaSR), isolated for the first time from bovine and human parathyroid, is a G-protein-coupled receptors that has been involved in diverse physiological functions. At present a complete in vivo work on the identification of CaSR mRNA-expressing cells in the adult brain lacks and this investigation was undertaken in order to acquire more information on cell type expressing CaSR mRNA in the rat brain and to analyse for the first time its expression in different experimental models of brain injury. The expression of CaSR mRNAs was found mainly in scattered cells throughout almost all the brain regions. A double labeling analysis showed a colocalization of CaSR mRNA expression in neurons and oligodendrocytes, whereas it was not found expressed both in the microglia and in astrocytes. One week after kainate-induced seizure CaSR was found in the injured CA3 region of the hippocampus and very interestingly it was found up-regulated in the neurons of CA1-CA2 and dentate gyrus. Similarly, 1 week following ibotenic acid injection in the hippocampus, CaSR mRNA expression was increased in oligodendrocytes both in the lesioned area and in the contralateral CA1-CA3 pyramidal cell layers and dentate gyrus. One week after needle-induced mechanical lesion an increase of labeled cells expressing CaSR mRNA was observed along the needle track. In conclusion, the present results contribute to extend available data on cell type-expressing CaSR in normal and injured brain and could spur to understand the role of CaSR in repairing processes of brain injury

Poorly differentiated clusters (PDC) in colorectal cancer: what is and ought to be known.

The counting of poorly differentiated clusters of 5 or more cancer cells lacking a gland-like structure in a tumor mass has recently been identified among the histological features predictive of poor prognosis in colorectal cancer. Poorly differentiated clusters can easily be recognized in the histological sections of colorectal cancer routinely stained with haematoxylin and eosin. Despite some limitations related to specimen fragmentation, counting can also be assessed in endoscopic biopsies. Based on the number of poorly differentiated clusters that appear under a microscopic field of a ×20 objective lens (i.e., a microscopic field with a major axis of 1 mm), colorectal cancer can be graded into malignancies as follows: tumors with <5 clusters as grade 1, tumors with 5 to 9 clusters as grade 2, and tumors with ≥10 clusters as grade 3. High poorly differentiated cluster counts are significantly associated with peri-neural and lympho-vascular invasion, the presence of nodal metastases or micrometastases, as well as shorter overall and progression free survival to colorectal cancer. The morphological aspects and clinical relevance of poorly differentiated clusters counting in colorectal cancer are discussed in this review

HER2 Status in Premalignant, Early, and Advanced Neoplastic Lesions of the Stomach

Objectives. HER2 expression in gastric cancer (GC) has received attention as a potential target for therapy with Trastuzumab. We reviewed the current knowledge on HER2 status in premalignant gastric lesions and in early (EGC) and advanced (AGC) GC to discuss the possible pathogenetic and prognostic roles of HER2 overexpression in GC. Results. HER2 overexpression was documented in gastric low-grade (LG) and high-grade intraepithelial neoplasia (HG-IEN), with higher frequency in gastric type dysplasia. HER2 overexpression was significantly associated with disease recurrence and poor prognosis in EGC representing an independent risk factor for lymph node metastases. HER2 overexpression was more frequent in AGC characterized by high grade, advanced stage, and high Ki-67 labeling index. The discordance in HER2 status was evidenced between primitive GC and synchronous or metachronous metastases. Conclusions. HER2 overexpression in premalignant gastric lesions suggests its potential involvement in the early steps of gastric carcinogenesis. The assessment of HER2 status in EGC may be helpful for the identification of patients who are at low risk for developing nodal metastases. Finally, the possible discordance in HER2 status between primary GC and its synchronous metastases support routine assessment of HER2 both in the primary GC and in its metastatic lesions

Clinical impact and prognostic role of KRAS/BRAF/PIK3CA mutations in stage I colorectal cancer

Stage I colorectal carcinoma has excellent prognosis, with 5-year survival rate up to 95%. The occurrence of lymphovascular invasion, tumor budding, high number of PDC, or lymph node micrometastases is associated with tumor progression. The aim of this study was to evaluate the mutational status of 62 stage I colorectal carcinomas (CRC) (taken from 37 patients surviving more than five years since the initial diagnosis and from 25 patients who died of disease) and to correlate it with histopathological features and the clinical outcome. Mutations of KRAS, NRAS, BRAF, and PIK3CA genes were analyzed through Myriapod Colon Status Kit, using the high-throughput genotyping platform Sequenom MassARRAY System. Mutations in those genes were found in 31 cases (50%) and mainly in those with poor prognosis. The most frequent mutations occurred at codons 12 and 13 of the KRAS gene (40% of cases). We found concomitant PIK3CA mutations in 5 cases (8%). The presence of PIK3CA mutations was mainly observed in tumors with poor prognosis and with unfavorable histopathological prognostic features. High PDC grade (P = 0 0112), the presence of tumor budding (P = 0 0334), LVI (P < 0 0001), KRAS mutations (P = 0 0228), PIK3CA mutations (P = 0 0214), multiple genetic mutations in KRAS and PIK3CA genes (P = 0 039), and nodal micrometastases (P < 0 0001) were significant prognostic variables for CSS. The presence of LVI was the only independent and statistically significant prognostic variable for CSS in our cohort of pTNM stage I CRCs. The analysis of KRAS/PIK3CA mutational status may be used to identify patients with stage I CRC at high risk of bad outcome and who may need additional treatments, including biological therapies

Human Epidermal Growth Factor Receptor 2 Status in Gastric Carcinomas with Distinctive Prevalent Cribriform Component

A cribriform architectural pattern has been reported in 9% of one unselected consecutively collected series of gastric carcinomas (GC) with unfavourable prognostic outcome. Taking into consideration the biological relevance of the human epidermal growth factor receptor 2 (HER2) status, we have analyzed a cohort of GC with a cribriform component more than 40% (CGC) to evaluate the HER2 amplification rate as a potential target for therapy with trastuzumab

Synthesis, spectroscopic characterization and in vitro antitumor activity of new trans 1-heteroaryl-2-(1-methylpyridinium-2-yl) ethylenes

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