Establishing a Multi-Vial Design Space for the Freeze-Drying Process by Means of Mathematical Modeling of the Primary Drying Stage.

Primary drying is the most critical stage of the freeze-drying process. This work aimed to establish a design space for this process by means of mathematical modeling of the primary drying stage, capable of addressing the thermal characteristics of distinct vial suppliers. Modeling of primary drying was implemented on Microsoft Excel using steady-state heat and mass transfer equations at two extreme conditions as assessed by risk analysis, to predict product temperature and primary-drying time. The heat transfer coefficients (Kv) of four different vial suppliers were experimentally determined, both, at the center and edge of the freeze-dryer's shelf. Statistically significant differences (ANOVA p<0.05) were observed between suppliers throughout the assessed pressure range. Overall, the average Kve/Kvc (edge/center) ratio was higher than 1.6 for all suppliers due to the radiation effect. A design space for the drying process was established using mathematical modeling taking into account the Kv of the worst-case supplier, in the shelf edge. A primary drying cycle was carried out at a shelf temperature of -25 °C and a chamber pressure of 45 mTorr for 8 % sucrose and at -10 °C and 75 mTorr for 5 % NaCl. Freeze-dried products with good cosmetic appearance were obtained for the four vial suppliers both, in the shelf center and edge. The results show that it is possible to predict and establish the critical parameters for the primary drying stage, under a design space concept, considering the differences in the Kv of vial suppliers without adverse consequences on the quality of the finished freeze-dried product.

Evaluation of an educational telephone intervention strategy to improve non-screening colonoscopy attendance: A randomized controlled trial.

BACKGROUND: Colonoscopy attendance is a key quality parameter in colorectal cancer population screening programmes. Within these programmes, educative interventions with bidirectional contact carried out by trained personnel have been proved to be an important tool for colonoscopy attendance improvement, and because of its huge clinical and economic impact, they have been widely implemented. However, outside of this population programmes, educative measures to improve colonoscopy attendance have been poorly studied and no navigation interventions are usually performed. AIM: To investigate the clinical and economic impacts of an educational telephone intervention on colonoscopy attendance outside colorectal cancer screening programmes. METHODS: This randomized controlled trial included consecutive patients referred to colonoscopy from primary care centres from November 2017 to May 2018. The intervention group (IG) received a telephone intervention, while the control group (CG) did not. Patients assigned to the IG received an educational telephone call 7 d before the colonoscopy appointment. The intervention was carried out by two nurses with deep endoscopic knowledge who were previously trained for a telephone educational intervention for colonoscopy. The impact on patient compliance with preparedness protocols related to bowel cleansing, anti-thrombotic management, and sedation scheduling was also evaluated. A second call was conducted to assess patient satisfaction. Intention-to-treat (ITT) and per-protocol (PP) analyses were performed. RESULTS: A total of 738 and 746 patients were finally included in the IG and CG respectively. Six hundred thirteen (83%) patients were contacted in the IG. The non-attendance rate was lower in the IG, both in the ITT analysis (IG 8.4% vs CG 14.3%, P < 0.001) and in the PP analysis (4.4% vs 14.3%, P < 0.001). In a multivariable analysis, belonging to the control group increased the risk of non-attendance in both, the ITT analysis (OR 1.81, 95%CI: 1.27 to 2.58, P = 0.001) and the PP analysis (OR 3.56, 95%CI: 2.25 to 5.64, P < 0.001). There was also a significant difference in compliance with preparedness protocols [bowel cleansing: IG 61.7% vs CG 52.6% (P = 0.001), antithrombotic management: IG 92.5% vs CG 62.8% (P = 0.001), and sedation scheduling: IG 78.8% vs CG 0% (P ≤ 0.001)]. We observed a net benefit of €55600/year after the intervention. The information given before the procedure was rated as excellent by 26% (CG) and 51% (IG) of patients, P ≤ 0.001. CONCLUSION: Educational telephone nurse intervention improves attendance, protocol compliance and patient satisfaction in the non-screening colonoscopy setting and has a large economic impact, which supports its imple-mentation and maintenance over time.

Distributed Fast Self-Organized Maps for Massive Spectrophotometric Data Analysis †.

Analyzing huge amounts of data becomes essential in the era of Big Data, where databases are populated with hundreds of Gigabytes that must be processed to extract knowledge. Hence, classical algorithms must be adapted towards distributed computing methodologies that leverage the underlying computational power of these platforms. Here, a parallel, scalable, and optimized design for self-organized maps (SOM) is proposed in order to analyze massive data gathered by the spectrophotometric sensor of the European Space Agency (ESA) Gaia spacecraft, although it could be extrapolated to other domains. The performance comparison between the sequential implementation and the distributed ones based on Apache Hadoop and Apache Spark is an important part of the work, as well as the detailed analysis of the proposed optimizations. Finally, a domain-specific visualization tool to explore astronomical SOMs is presented.

A novel and highly regioselective synthesis of new carbamoylcarboxylic acids from dianhydrides.

A regioselective synthesis has been developed for the preparation of a series of N,N'-disubstituted 4,4'-carbonylbis(carbamoylbenzoic) acids and N,N'-disubstituted bis(carbamoyl) terephthalic acids by treatment of 3,3',4,4'-benzophenonetetracarboxylic dianhydride (1) and 1,2,4,5-benzenetetracarboxylic dianhydride (2) with arylalkyl primary amines (A-N). The carbamoylcarboxylic acid derivatives were synthesized with good yield and high purity. The specific reaction conditions were established to obtain carbamoyl and carboxylic acid functionalities over the thermodynamically most favored imide group. Products derived from both anhydrides 1 and 2 were isolated as pure regioisomeric compounds under innovative experimental conditions. The chemo- and regioselectivity of products derived from dianhydrides were determined by NMR spectroscopy and confirmed by density functional theory (DFT). All products were characterized by NMR, FTIR, and MS.

Predictive factors of radiation dose in ERCP: a prospective study in 2 tertiary centers.

BACKGROUND: The use of fluoroscopy to aid endoscopic retrograde cholangiopancreatography (ERCP) places both the patient and the endoscopy staff at the risk of radiation-induced injury. Previous reports have demonstrated a linear relationship between radiation dose and fluoroscopy duration. AIM: To identify predictive factors of fluoroscopy time and radiation exposure to patients undergoing ERCP by using pulsed fluoroscopy. METHODS: Four hundred and four consecutive ERCPs performed from January 2010 to November 2010 at 2 tertiary centers in Spain were prospectively studied. Patients and procedural variables were analyzed. Philips BV Pulsera mobile fluoroscopy system was used on the endoscopy unit. Entrance surface dose, dose-area product, and fluoroscopy time were recorded for each patient. RESULTS: A total of 404 ERCPs on 404 consecutive patients were studied (mean age 73 y). The average entrance surface dose and dose-area product were 12.0 mGy and 0.37 mGy/m2, respectively. Mean fluoroscopy time was 2.31 minutes. The biliary ducts were adequately visualized in 371 (92%) cases. After analysis with a univariable model, the factors found to significantly increase the radiation dose (P75>19.6 mGy) were as follows: alkaline phosphatase serum levels (P=0.047), balloon dilation (P=0.005), biliary stent placement (P=0.001), and ERCP diagnosis (P=<0.0001). In a multivariate analysis, only stent insertion significantly increased the radiation dose (risk ratio 4.75; 95% confidence interval, 1.84-7.63). CONCLUSIONS: In this prospective analysis, multiple factors affected the radiation dose. Stent insertion was the only independent predictor significantly associated with prolonged fluoroscopy.

A new protein graph model for function prediction.

As several structural proteomic projects are producing an increasing number of protein structures with unknown function, methods that can reliably predict protein functions from protein structures are in urgent need. In this paper, we present a method to explore the clustering patterns of amino acids on the 3-dimensional space for protein function prediction. First, amino acid residues on a protein structure are clustered into spatial groups using hierarchical agglomerative clustering, based on the distance between them. Second, the protein structure is represented using a graph, where each node denotes a cluster of amino acids. The nodes are labeled with an evolutionary profile derived from the multiple alignment of homologous sequences. Then, a shortest-path graph kernel is used to calculate similarities between the graphs. Finally, a support vector machine using this graph kernel is used to train classifiers for protein function prediction. We applied the proposed method to two separate problems, namely, prediction of enzymes and prediction of DNA-binding proteins. In both cases, the results showed that the proposed method outperformed other state-of-the-art methods.

A graph-based semantic similarity measure for the gene ontology.

Existing methods for calculating semantic similarities between pairs of Gene Ontology (GO) terms and gene products often rely on external databases like Gene Ontology Annotation (GOA) that annotate gene products using the GO terms. This dependency leads to some limitations in real applications. Here, we present a semantic similarity algorithm (SSA), that relies exclusively on the GO. When calculating the semantic similarity between a pair of input GO terms, SSA takes into account the shortest path between them, the depth of their nearest common ancestor, and a novel similarity score calculated between the definitions of the involved GO terms. In our work, we use SSA to calculate semantic similarities between pairs of proteins by combining pairwise semantic similarities between the GO terms that annotate the involved proteins. The reliability of SSA was evaluated by comparing the resulting semantic similarities between proteins with the functional similarities between proteins derived from expert annotations or sequence similarity. Comparisons with existing state-of-the-art methods showed that SSA is highly competitive with the other methods. SSA provides a reliable measure for semantics similarity independent of external databases of functional-annotation observations.

A shortest-path graph kernel for estimating gene product semantic similarity.

BACKGROUND: Existing methods for calculating semantic similarity between gene products using the Gene Ontology (GO) often rely on external resources, which are not part of the ontology. Consequently, changes in these external resources like biased term distribution caused by shifting of hot research topics, will affect the calculation of semantic similarity. One way to avoid this problem is to use semantic methods that are "intrinsic" to the ontology, i.e. independent of external knowledge. RESULTS: We present a shortest-path graph kernel (spgk) method that relies exclusively on the GO and its structure. In spgk, a gene product is represented by an induced subgraph of the GO, which consists of all the GO terms annotating it. Then a shortest-path graph kernel is used to compute the similarity between two graphs. In a comprehensive evaluation using a benchmark dataset, spgk compares favorably with other methods that depend on external resources. Compared with simUI, a method that is also intrinsic to GO, spgk achieves slightly better results on the benchmark dataset. Statistical tests show that the improvement is significant when the resolution and EC similarity correlation coefficient are used to measure the performance, but is insignificant when the Pfam similarity correlation coefficient is used. CONCLUSIONS: Spgk uses a graph kernel method in polynomial time to exploit the structure of the GO to calculate semantic similarity between gene products. It provides an alternative to both methods that use external resources and "intrinsic" methods with comparable performance.

Efecto cardíaco del extracto de epitelio pigmentado de la retina (melanina), del globo ocular de embrión de pollo “in vivo” e “in vitro” / Cardiac effect of the extract of retinal pigment epithelium (melanin) of the eyeball chick embryo

La melanina y su participación en la génesis de ciertas patologías cardíacas, ha sido revisada recientemente. Sin embargo, la expresión funcional y celular del efecto sobre el corazón no ha sido claramente establecida. En el presente trabajo se hizo uso del extracto de epitelio pigmentado de la retina del globo ocular de embrión de pollo, contentivo de melanina, para estudiar "in vivo" el patrón de contracción del corazón y la frecuencia cardíaca por videocardiograma, un método semi-invasivo en embriones de pollo de 3d-4d días de incubación, e "in vitro", su efecto sobre el patrón mitocondrial de mioblastos cardíacos en cultivo primario de Gota pendiente, incubados con el fluorocromo catiónico, 3,3´-dimetiloxicabonocianida (DiOC1 [3]). El tratamiento promovió una disfunción de la contracción peristáltica del corazón embrionario, con un incremento en el llenado auricular y una reducción de llenado ventricular durante las diástoles. Se determinó una reducción significativa de frecuencia cardíaca del 18,73 por ciento, luego de una hora de tratamiento. A diferencia de los controles, con un patrón homogéneo de fluorescencia verde emitido por las mitocondrias de forma alargada, la población de mioblastos tratados mostró un patrón de fluorescencia difusa, mitocondrias redondeadas y se observó la presencia de blebs a nivel de la superficie celular. Los resultados sugieren que el extracto de epitelio pigmentado de retina, contentivo de melanina, altera la contracción peristáltica e induce una reducción de la frecuencia cardíaca en modelo experimental de embrión de pollo, acompañada con un daño en las mitocondrias, probablemente vinculado a la activación de un proceso de muerte celular mediado por factores apoptoticos mitocondriales que podrían estar asociados a tales efectos

Melanin and its involvement in the genesis of certain cardiac diseases, has recently been revised. However, the expression of functional and cellular effects on the heart has not been clearly established. In this paper we made use of the extract of the retinal pigmented epithelium of the eyeball of the chick embryo, containing melanin, to study "in vivo" the pattern of contraction of the heart and the heart rate by Videocardiograma semi-invasive method in embryos of 3d-4d days of incubation, and in vitro, their effect on the pattern of mitochondrial using Hanging drop method, to primary culture of cardiac myoblasts, incubated with the cationic fluorochrome, 3,3-dimetiloxicabonocianida (DiOC1 [3]). The treatment promoted a malfunction of the peristaltic contraction of the embryonic heart, with an increase in atrial filling and reduced ventricular filling during diastole. We determined a significant reduction in heart rate of 18.73 percent, after an hour of treatment. The population of myoblasts showed a diffuse pattern of fluorescence, mitochondria were rounded and the cytoplasm showed the presence of blebs at the surface unlike controls with a uniform pattern of green fluorescence emitted by the elongated shape of mitochondria. The results suggested that the extract of retinal pigmented epithelium, melanin containing, alters the peristaltic contraction and decrease the heart rate in experimental model of chick embryo, together with mitochondrial damage, probably linked to the activation of a process of cell death mediated by factors apoptotic mitochondria, which could be associated with such effects

Cyclosporin A promotes mineralization by human cementoblastoma-derived cells in culture.

OBJECTIVE: The immunosuppressive drug cyclosporin A has been shown to induce cementum deposition in vivo in experimental animals. Using cementoblastoma-derived cells, we have studied whether this drug will be useful to study cementum mineralization and differentiation in vitro. METHODS: Human cementoblastoma cells and gingival fibroblasts (controls) were cultured and treated with 0.5, 1.0 and 5.0 microg/ml of cyclosporin A. Cell proliferation was evaluated by MTT (tetrazolium) assay and cell number, and cell viability was assessed by trypan blue dye exclusion. Induction of mineralization was evaluated by alizarin red S staining to detect mineralized nodules and by reverse transcription-polymerase chain reaction (RT-PCR) to assess the expression of bone differentiation markers alkaline phosphatase, osteocalcin, bone sialoprotein and core-binding factor a1 (Cbfa1). RESULTS: Cyclosporin A at 5.0 microg/ml concentration reduced significantly the increase in the number of cementoblastoma cells. A dose-dependent increase in the number of mineralized nodules occurred in cultures of cementoblastoma-derived cells treated with cyclosporin A, and RT-PCR analyses showed significantly higher levels of expression of alkaline phosphatase, bone sialoprotein, type I collagen, matrix metalloproteinase-1, osteocalcin, osteopontin, and Cbfa1. Human gingival fibroblast proliferation and cell number were not affected. Mineralized nodules were not detected in gingival fibroblasts and bone specific proteins were not expressed. CONCLUSIONS: Presence of cyclosporin A during 14-day culture period appears to suppress the proliferation of cementoblastoma cells and induce the formation mineralized-like tissue by these cells.

Combining steroids with enteral nutrition: a better therapeutic strategy for severe alcoholic hepatitis? Results of a pilot study.

BACKGROUND: Results of a previous randomized controlled trial comparing the outcome of patients with severe alcoholic hepatitis treated with total enteral nutrition (TEN) or corticosteroids suggest that these treatments act through different mechanisms and may be complementary. We report a pilot study of combined treatment with TEN and a shorter course of steroids in patients with severe alcoholic hepatitis. METHODS: Thirteen patients with severe alcoholic hepatitis were treated with systemic steroids and TEN. Steroid therapy started with 40 mg oral prednisolone daily, and was progressively tapered as soon as both serum bilirubin and prothrombin time decreased below 50% of their baseline values. TEN (2000 kcal, or 8374 kJ, daily) was administered throughout the hospital stay. Patients were followed for at least 12 months or until death. RESULTS: Tapering of prednisolone dose could be started after a mean (SD) of 15.4 (3.8) days, whereas TEN was maintained for 22 (3.8) days. TEN was tolerated in 10 of the 13 patients. The major adverse event attributable to therapy was hyperglycemia requiring insulin therapy, which occurred in 12 of 13 patients. Only two patients (15%) died during the treatment period. Another patient died within the first 2 months of follow-up. In no case was the death due to infectious complications, despite two-thirds of patients developing infections during the treatment period. Infections during follow-up occurred only in three patients. CONCLUSION: This pilot study suggests that TEN associated with a short course of steroids could be a good therapeutic strategy for severe alcoholic hepatitis. This possibility deserves investigation in a randomized controlled trial.

Oral bile acids reduce bacterial overgrowth, bacterial translocation, and endotoxemia in cirrhotic rats.

Experiments were performed to test whether conjugated bile acid administration would decrease bacterial overgrowth, bacterial translocation, and endotoxemia in ascitic cirrhotic rats. Cholylsarcosine, a deconjugation-dehydroxylation resistant and cholylglycine, a deconjugation-dehydroxylation susceptible bile acid were used. Rats with CCl(4)-induced cirrhosis and ascites were fed cholylsarcosine, cholylglycine (both at 70 mg/kg/d), or placebo for 2 weeks. Healthy rats, as controls, were treated similarly. In cirrhotic rats receiving placebo, bile secretion from an acute biliary fistula was lower than in healthy rats (27.2 +/- 6.5 vs. 53.0 +/- 3.1 microL/kg/min; mean +/- SE, P<.05). The administration of conjugated bile acids to cirrhotic rats normalized bile secretion (cholylsarcosine, 51.8 +/- 6.29; cholylglycine, 52.72 +/- 8.9 microL/kg/min). Total ileal bacterial content was 6-fold higher in ascitic cirrhotic rats than in healthy rats. Conjugated bile acid administration reduced bacterial content to normal levels. Bacterial translocation was less in cirrhotic animals receiving conjugated bile acids (cholylsarcosine, 33%; cholylglycine, 26%) than in animals receiving placebo (66%). Endotoxemia was decreased in cirrhotic rats by conjugated bile acid feeding (cholylsarcosine, 0.098 +/- 0.002; cholylglycine 0.101 +/- 0.007 EU/mL) compared with placebo (0.282 +/- 0.124, P <.001). Survival was greater in animals receiving conjugated bile acids (cholylsarcosine, 10/15; cholylglycine, 11/15; placebo, 5/15). In conclusion, the administration of conjugated bile acids to ascitic cirrhotic rats increased bile acid secretion, eliminated intestinal bacterial overgrowth, decreased bacterial translocation, decreased endotoxemia, and increased survival. Oral conjugated bile acids may be useful in preventing bacterial translocation, endotoxemia, and spontaneous bacterial perotonitis in cirrhotic patients.