Tunable Surface Patterning of Azopolymer by Vectorial Holography: The Role of Photoanisotropies in the Driving Force.

The capability to pattern polymer surfaces at different length scales is an important goal in different research fields, including display technologies, microelectronics, optics, as well as biorelated and medical science. However, the ability to optically and dynamically manipulate topography is a key feature enabling remote control of associated effects/processes mediated by the surface. Azopolymers are largely investigated to this aim based on their sensitivity to optical fields and reconfigurability capabilities. In this work, surface relief formation induced by polarization patterns on an amorphous azopolymer structurally engineered to have large photoinduced birefringence has been investigated both experimentally and theoretically. Based on the different light polarization patterns, depth and shape of the relief grating can be controlled. An optically induced gradient force model that includes both the spatial distribution and the anisotropy of the material permittivity has been theoretically analyzed. The proposed approach is able to explain the experimental results and to overcome the limitation of existing models.

Clinical results of infrared coagulation as a treatment of high-grade anal dysplasia: a systematic review.

BACKGROUND: Anal intraepithelial neoplasia (AIN) (or low/high grade squamous intraepithelial neoplasia (L/HSIL)) is the precursor of anal of early invasive anal cancer. Different treatment options for local ablation of localized lesions have been reported. The aim of this study was to analyze the clinical efficacy and safety of infrared coagulation for the treatment of anal dysplasia. METHODS: A search of the literature was performed in 2019 using PubMed and Cochrane to identify all eligible trials published reporting data on the treatment of anal dysplasia with infrared coagulation. The percentage of squamous cell carcinoma of the the anus that developed in the follow-up and results on major complications after treatment were the primary outcomes. RESULTS: Twenty-four articles were identified from which 6 were selected with a total of 360 patients included, with a median age of 41.8 years. Three studies were prospective and 3 retrospective, only one was a randomized trial. All articles included males, 4 articles included HIV-positive women and only one article included non HIV infected males. No patient developed major complications after infrared coagulation therapy. Pain was the most common symptom found after the procedure in the different series and mild bleeding that did not require transfusion was the most common complication occurring in 4 to 78% of patients. Median follow-up was between 4.7 and 69 months. No patient developed squamous cell carcinoma after infrared treatment. Recurrent HSIL varied from 10 to 38%. Two studies reported results from follow-up of untreated patients showing that between 72 and 93% of them had persistent HSIL at last follow-up and 4.8% developed squamous cell carcinoma. CONCLUSIONS: Infrared coagulation is a safe and effective method for ablation of high-grade anal dysplasia that could help prevent anal cancer. Continued surveillance is recommended due to the risk of recurrence.

Silver-embedded screens in the intensive care unit. A new tool to control multi-drug resistant bacterial cross-transmission.

The purpose of this study was to assess the effectiveness of silver-embedded surfaces (BactiBlock®) to prevent surface colonization by multi-resistant bacteria (MRB) and to reduce the incidence of MRB colonization and infection in patients admitted to an intensive care unit (ICU). A 6-month prospective observational study in a 24-bed mixed ICU divided into two identical subunits (12 beds each) was designed. Seven solid mobile screens were placed in one of the subunits while in the other cloth screens remained. Solid screens were constructed with high-density polyethylene embedded in Bactiblock®. To evaluate the effectiveness of screens coated with Bactiblock®, number of MRB isolates on screens were compared for 6 months. Likewise, numbers of new patients and ICU-stays with MRB colonization in the two subunits were compared. One hundred forty screen samples were collected in 10-point prevalent days. MRB were detected on 28 (20.0%) samples. Over the 70 samples taken on cloth folding screens, MRB were detected in 25 (35.7%), while only 3 (4.3%) of the 70 samples taken on Bactiblock® screens were positive for MRB (p < 0.001). The unit with Bactiblock® screens presented fewer number of ICU stays with MRB colonization (27.8% vs 47.1%; p < 0.001). No significant differences were found in the global incidence of MRB nosocomial infection. The presence of Bactiblock® embedded in solid folding screens avoided MRB surface colonization and reduced MRB transmission to patients admitted to critical care units, proving to be an useful tool in the control of MRB.

Condylomata, cytological abnormalities and human papillomavirus infection in the anal canal in HIV-infected men.

BACKGROUND: Genital infections with low-risk (LR) and high-risk (HR) human papillomavirus (HPV) genotypes are associated with ano-genital condylomata and anal squamous cell cancer. HPV-related pathologies in HIV-infected men are a serious concern. In this study, the prevalence of anal condylomata and their association with cytological abnormalities and HPV infection in the anal canal in HIV-infected men [men who have sex with men (MSM) and heterosexuals] were estimated. METHODS: This was a cross-sectional study based on the first visits of patients in the Can Ruti HIV-positive Men (CARH·MEN) cohort. Anal condylomata were assessed by clinical and proctological examination. Samples from the anal canal were collected for HPV genotyping and cytological diagnoses. RESULTS: A total of 640 HIV-infected men (473 MSM and 167 heterosexuals) were included in the study. The overall prevalence of anal condylomata was 25% [157 of 640; 95% confidence interval (CI) 21-28%]; in MSM it was 28% and in heterosexuals it was 15% [odds ratio (OR) 2.2; 95% CI 1.4-3.5]. In patients with anal condylomata, HPV infection in the anal canal was more prevalent (92% vs. 67% in those without anal condylomata; OR 8.5; 95% CI 3.2-22). This higher HPV prevalence involved at least two HPV genotypes (OR 4.0; 95% CI 2.2-7.1), mainly HR genotypes (OR 3.3; 95% CI 1.7-6.4). Similarly, the cumulative prevalence of HPV-6 and HPV-11 was higher in patients with anal condylomata (63% vs. 19% in those without anal condylomata). Having anal condylomata was associated with higher prevalences of cytological abnormalities (83% vs. 32% in those without anal condylomata; OR 6.9; 95% CI 3.8-12.7) and high-grade squamous intraepithelial lesions (HSILs) (9% vs. 3% in those without anal condylomata; OR 9.0; 95% CI 2.9-28.4) in the anal canal. CONCLUSIONS: HIV-infected men with anal condylomata were at risk of presenting HSILs and harbouring multiple HR HPV infections in the anal canal. Although MSM presented the highest prevalence of anal condylomata, heterosexual men also had a clinically important prevalence. Our findings emphasize the importance of screening and follow-up for condylomata in the anal canal in HIV-infected men.

Human papillomavirus HPV-16, 18, 52 and 58 integration in cervical cells of HIV-1-infected women.

BACKGROUND: Genomic integration of high-risk human papillomavirus into the cellular genome is considered an important event in the pathogenesis of cervical cancer related to the progression from premalignant cervical lesions to invasive cervical carcinoma. OBJECTIVE: This cross-sectional study was aimed to characterize the viral integration of HPV-16, HPV-18, HPV-52 and HPV-58 in cervical cells. STUDY DESIGN: HPV genotypes were determined by PCR and HPV integration by multiplex PCR in HIV-1-infected women without a background of HPV-related pathology. RESULTS: This study included 251 cervical cells samples of consecutive HIV-positive women who were visited between 1999 and 2003. The overall prevalence of HPV infection was 53% (133/251, 95%CI: 47-59%). The most prevalent genotypes were HPV-16 (27%), HPV-33 (15%), HPV-52 (8%) and HPV-58 (8%). The prevalence of abnormal cervical cytology was 33% (83/251, 95%CI: 27-39%). The overall prevalence of HPV integration was 11% (27/251, 95%CI: 7-15%), and the prevalence of HPV-16 integration was 33% (22/67, 95%CI: 22-45%), HPV-18 integration was 30% (3/10, 95%CI: 7-65%) and HPV-52 integration was 10% (2/19, 95%CI: 1-32%). No HPV-58 integration was detected. The percentage of HPV-16 and HPV-18 integration increased with the severity of the cervical lesions, HPV-16 integration was almost 70% and HPV-18 integration was 50% in high-grade squamous intraepithelial lesions. Integration was the most important risk factor associated with cervical dysplasia (OR=30.6, 95%CI: 3.5-270.6). CONCLUSION: HPV integration might represent a good biomarker of the evolution from HPV infection to cervical cancer. Further prospective studies are required to validate our findings.

Effect of taxol feeding on taxol and related taxane production in Taxus baccata suspension cultures.

To achieve a better understanding of taxol metabolism and accumulation in Taxus cell cultures, a T. baccata cell line growing for 20 days in a selected growth medium was treated at the beginning of the experiment with several concentrations of taxol (25, 50, 100 and 200mgL(-1)). Compared with an untreated control, all these taxol concentrations stimulated cell-associated taxol content (up to 32.7 times in the presence of 200mgL(-1) exogenous taxol), although higher concentrations significantly depressed cell viability. DNA laddering analysis revealed that the viability reduction was not related to apoptosis, suggesting that taxol itself was the primary responsible factor. On the basis of RT-PCR expression analysis of genes encoding taxadiene synthase (ts) and 1-deoxy-d-xylulose-5-phosphate synthase (dxs) from treated and nontreated T. baccata cell line cultures, it was observed that exogenous taxol clearly induced the mRNA levels of both taxane-related enzymes. Additionally, we found that exogenous taxol caused a considerable increase in taxadiene synthase activity, although in no case did this coincide with the highest levels of taxol observed at the end of the culture. The effect of exogenous taxol on the content of other related taxanes was also considered.

Personal and organizational determinants of well-being at work: the case of Swedish physicians.

PURPOSE: The traditional perspective in the occupational and organizational psychology literature aimed at understanding well-being, has focused almost exclusively on the "disease" pole. Recently, however, new concepts focusing on health are emerging in the so-called "positive psychology" literature. The purpose of this paper is to test multiple possible linkages (or profiles) between certain personal, organizational, and cultural variables that affect both burnout and vigor. Burnout (disease) and vigor (health) are assumed to represent two extreme poles of the well-being phenomenon. DESIGN/METHODOLOGY/APPROACH: An innovative statistical treatment borrowed from data mining methodology was used to explore the conceptual model that was utilized. A self-administered questionnaire from a sample of 1,022 physicians working in Swedish public hospitals was used. Standardized job/work demands with multiple items were employed in conjunction with the Uppsala Burnout scale, which was dichotomized into high (burnout) and low (vigor) score. A combination of ANOVAs and "classification and regression tree analyses" was utilized to test the relationships and identify profiles. FINDINGS: Results show an architecture that predicts 59 percent of the explained variance and also reveals four "tree branches" with distinct profiles. Two configurations indicate the determinants of high-burnout risk, while two others indicate the configurations for enhanced health or vigor. ORIGINALITY/VALUE: In addition to their innovative-added value, the results can also be most instrumental for individual doctors and hospitals in gaining a better understanding of the aetiology of burnout/vigor and in designing effective preventative measures for reducing risk factors for burnout, and enhancing well-being (vigor).

Immobilization of Galphimia glauca plant cell suspensions for the production of enhanced amounts of Galphimine-B.

We tested the capacity of Galphimia glauca cells to produce galphimine-B (G-B) when under the effects of a two-stage culture system: cell immobilization in Ca2+-alginate beads and culture scale-up from shake-flask to two different types of bioreactor (stirred and airlift). In the shake-flask culture, using optimum media for cell growth (first stage) and G-B production (second stage), the G-B yield was similar in both immobilised and free cells. However, while the free cells accumulated G-B within cytoplasmatic compartments, where it could not be recovered without cell disruption, immobilized cells excreted up to 100 % of the G-B produced. Immobilized cells grown in bioreactors running for 14 days with growth medium and an additional 26 days with production medium in batch mode showed a high G-B yield. The stirred bioreactor was the most efficient with a G-B content in the culture medium of 1381 microg.L (-1) at day 24 of culture.

Biotransformation of hyoscyamine into scopolamine in transgenic tobacco cell cultures.

Hyoscyamine-6beta-hydroxylase (H6H) catalyses the conversion of hyoscyamine into its epoxide scopolamine, a compound with a higher added value in the pharmaceutical market than hyoscyamine. We report the establishment of tobacco cell cultures carrying the Hyoscyamus muticus h6h gene under the control of the promoter CAMV 35S. The cell cultures were derived from hairy roots obtained via genetically modified Agrobacterium rhizogenes carrying the pRi and pLAL21 plasmids. The cultures were fed with hyoscyamine, and 4 weeks later the amount of scopolamine produced was quantified by HPLC. The transgenic cell suspension cultures showed a considerable capacity for the bioconversion of hyoscyamine into scopolamine, and released it to the culture medium. Although the scale-up from shake-flask to bioreactor culture usually results in reduced productivities, our transgenic cells grown in a 5-L turbine stirred tank reactor in a batch mode significantly increased the scopolamine accumulation.

The effect of methyl jasmonate on triterpene and sterol metabolisms of Centella asiatica, Ruscus aculeatus and Galphimia glauca cultured plants.

Considering that exogenously applied methyl jasmonate can enhance secondary metabolite production in a variety of plant species and that 2,3-oxidosqualene is a common precursor of triterpenes and sterols in plants, we have studied Centella asiatica and Galphimia glauca (both synthesizing triterpenoid secondary compounds) and Ruscus aculeatus (which synthesizes steroidal secondary compounds) for their growth rate and content of free sterols and respective secondary compounds, after culturing with or without 100 microM methyl jasmonate. Our results show that elicited plantlets of G. glauca and to a higher degree C. asiatica (up to 152-times more) increased their content of triterpenoids directly synthesized from 2,3-oxidosqualene (ursane saponins and nor-seco-friedelane galphimines, respectively) at the same time as growth decreased. In contrast, the free sterol content of C. asiatica decreased notably, and remained practically unaltered in G. glauca. However, in the case of R. aculeatus, which synthesizes steroidal saponins (mainly spirostane type) indirectly from 2,3-oxidosqualene after the latter is converted to the plant phytosterol-precursor cycloartenol, while the growth rate and free sterol content clearly decreased, the spirostane saponine content was virtually unchanged (aerial part) or somewhat lower (roots) in presence of the same elicitor concentration. Our results suggest that while methyl jasmonate may be used as an inducer of enzymes involved in the triterpenoid synthesis downstream from 2,3-oxidosqualene in both C. asiatica and G. glauca plantlets, in those of C. asiatica and R. aculeatus it inhibited the enzymes involved in sterol synthesis downstream from cycloartenol.

Effect of organogenesis on steroidal saponin biosynthesis in calli cultures of Ruscus aculeatus.

Calli cultures derived from Ruscus aculeatus rhizomes were investigated for their potential to biosynthesize saponins. The capacity of undifferentiated tissues to form steroidal saponins is very limited, but when the calli developed organogenesis, mainly aerial shoots and roots, the saponin production increased significantly. Plantlets regenerated from aerial shoots of Ruscus calli showed a saponin pattern similar to that of the callus cultures but the levels of saponins found in the aerial part and roots were significantly greater.

Identification of triterpenoid compounds of Centella asiatica by thin-layer chromatography and mass spectrometry.

The identification of the four principal triterpenoid components of Centella asiatica has been achieved by TLC on silica gel plates and mass spectrometry, as a modification of the method described in the European Pharmacopoeia (5th edn). A combination of ethyl acetate and methanol as the mobile phase was found to be successful in separating these compounds from the rest of the main components of the extract. The spots were detected with anisaldehyde solution. The separated compounds were confirmed by MALDI -TOF mass spectrometry.

Enhanced secretion of tropane alkaloids in Nicotiana tabacum hairy roots expressing heterologous hyoscyamine-6beta-hydroxylase.

Hyoscyamine-6beta-hydroxylase (H6H; EC 1.14.11.11) catalyses oxidative reactions in the biosynthetic pathway leading from hyoscyamine to the more pharmaceutically valuable tropane alkaloid scopolamine. The h6h gene encoding H6H from Hyoscyamus niger was introduced, under the control of the CaMV 35S promoter, into non-hyoscyamine-producing Nicotiana tabacum and hyoscyamine-producing Hyoscyamus muticus. The transformation was performed using a binary vector system based on Agrobacterium rhizogenes. Production of scopolamine in hairy roots was clearly correlated with the 35S-h6h transcript expression. The engineered N. tabacum and H. muticus hairy roots were studied for the production of scopolamine and other tropane and nicotine alkaloids after feeding the cultures with exogenous hyoscyamine. N. tabacum hairy roots carrying the 35S-h6h transgene showed a more efficient uptake of hyoscyamine from the culture medium and a higher rate of bioconversion of hyoscyamine to scopolamine than those of H. muticus. In particular, the secretion of scopolamine in N. tabacum hairy roots was remarkably high, up to 85% of the total scopolamine being released to the culture medium. Exogenous hyoscyamine also caused changes in nicotine alkaloid accumulation in N. tabacum hairy roots.

Effects of immobilization by entrapment in alginate and scale-up on paclitaxel and baccatin III production in cell suspension cultures of Taxus baccata.

Paclitaxel and baccatin III-producing cells of Taxus baccata were immobilized within Ca(2+)-alginate beads. Under established optimum conditions for the biosynthesis of both taxanes, the yields of paclitaxel and baccatin III in shake-flask cultures of free cells increased by factors of up to 3 and 2, respectively, in the corresponding cultures of immobilized cells. Although the scale-up from shake-flask to bioreactor culture usually results in reduced productivities when both free and immobilized cells were grown in the same optimum conditions in three different bioreactor types (Stirred, Airlift, and Wave) running for 24 days in a batch mode and with the system optimized in each case, there was a considerable increase in the yields of paclitaxel and baccatin III. Among the reactors, the Stirred bioreactor was the most efficient in promoting immobilized cell production of paclitaxel, giving a content of 43.43 mg.L(-1) at 16 days of culture, equivalent to a rate of 2.71 mg.L(-1).day(-1). To our knowledge, the paclitaxel productivity obtained in this study is one of the highest reported so far by academic laboratories for Taxus species cultures in bioreactors.

[Azathioprine and mesalazine in the prevention of postsurgical recurrence of Crohn's disease: a retrospective study]. / Azatioprina y mesalazina en la prevención de la recurrencia posquirúrgica en la enfermedad de Crohn: estudio retrospectivo.

OBJECTIVES: Surgical resection is still a mainstay of the treatment of Crohn's disease (CD). However, recurrence is the rule. The aim of the present study was to evaluate CD recurrence in a series of patients who underwent surgical resection with subsequent treatment with azathioprine (AZA) or mesalazine (5-ASA) and to identify the factors associated with recurrence. METHODS: The medical records of patients with CD who underwent bowel resection during a 4-year period were reviewed. Only patients who received AZA or 5-ASA as prophylaxis for recurrence were included. RESULTS: Thirty-three patients treated with AZA and 16 treated with 5-ASA were included. Endoscopic recurrence was found in 8.6% of the AZA group and in 87.5% of the 5-ASA group (p <0.001). Clinical recurrence occurred in 31.2% of patients in the 5-ASA group and in none in the AZA group (p=0.004). The accumulated probability of both clinical and endoscopic recurrence was significantly lower in the AZA group (p=0.0025 and p=0.005, respectively). Factors associated with a greater risk of endoscopic recurrence were termino-terminal anastomosis and 5-ASA treatment. The only factor associated with clinical recurrence was 5-ASA treatment. CONCLUSION: AZA seems to be more effective than 5-ASA in the prevention of postsurgical endoscopic recurrence of CD. Prospective studies with long-term follow-up are required to establish the true utility of AZA in the prophylaxis of CD recurrence.

Tratamiento farmacológico de la taquicardia supraventricular paroxística en una mujer embarazada / Pharmacologic treatment of paroxysmal supraventricular tachycardia in pregnancy

Los cambios fisiológicos que se producen en el sistema cardiovascular durante el embarazo son los que justifican que se produzca un estado proarritmógeno característico, siendo la taquicardia paroxística supraventricular (TSV) una de las arritmias más frecuentes durante el embarazo. Presentamos una embarazada de 15 semanas con TSV, que fue tratada con adenosina, revirtiendo a ritmo sinusal. Revisamos los tratamientos de la TSV en la gestante. Debemos hacer hincapié en la falta de estudios serios que valoren el empleo de uno u otro fármaco. Los artículos hacen referencia a casos aislados o series cortas en los que cuentan la experiencia obtenida en el uso de estos fármacos. Se ha venido empleando el propanolol, el verapamilo y la adenosina, siendo esta última la que se considera actualmente de elección frente a la taquicardia paroxística supraventricular en la embarazada. Ello se debe a las características farmacodinámicas de las que goza este fármaco, que hace que sea seguro tanto para la madre como para el feto (AU)

Growth and ginsenoside production in hairy root cultures of Panax ginseng using a novel bioreactor.

We tested the effect of three variables: the bioreactor system (Wave or Spray reactor), medium exchange and culture period, on the capacity of a selected hairy root line of Panax ginseng to produce ginsenosides. Among the reactors, the Wave bioreactor appeared to be the most efficient in promoting hairy root line growth. Periodic exchanges of the medium and a longer culture period increased the growth rate of cultured hairy root line and, consequently, its capacity to produce ginsenosides. Under established optimum conditions (medium exchange every 14 days over a culture period of 56 days using the Wave bioreactor), the initial root fresh weight was enhanced more than 28-fold, giving a root biomass of 284.9 g L(-1) and a ginsenoside content of 145.6 mg L(-1). It is noteworthy that this ginsenoside production exceeded by almost 3-fold that obtained during the shake flask culture of our hairy root line, although it often happens that the scale-up from shake flask to a bioreactor culture results in reduced productivities. To our knowledge this is the first time that a Wave bioreactor has been used for hairy root culture.

Inhibition of paclitaxel and baccatin III accumulation by mevinolin and fosmidomycin in suspension cultures of Taxus baccata.

To achieve a better understanding of the metabolism and accumulation of paclitaxel and baccatin III in cell cultures of Taxus, inhibitors of the early steps in the terpenoid pathway were applied to a cell suspension culture of Taxus baccata: fosmidomycin as an inhibitor of the non-mevalonate branch of the pathway, and mevinolin as an inhibitor of the mevalonate branch. Synthesis of both taxanes in the cell suspension was first increased when cultured in the product formation medium supplemented with methyljasmonate (100 microM). The product formation medium was selected after assaying 24 different culture media. When fosmidomycin (200 microM) was added to the product formation medium together with the elicitor, the accumulation of paclitaxel and baccatin III was reduced by up to 3.0 and 1.5 times, respectively, whereas the inhibitory effect of mevinolin (1 microM) was only clearly exerted in the case of paclitaxel. Under the conditions of our experiment, we conclude that in the synthesis of both taxanes, the non-mevalonate pathway is the main source of the universal terpenoid precursor isopentenyl diphosphate (IPP).

Effect of pmt gene overexpression on tropane alkaloid production in transformed root cultures of Datura metel and Hyoscyamus muticus.

In order to increase the production of the pharmaceuticals hyoscyamine and scopolamine in hairy root cultures, a binary vector system was developed to introduce the T-DNA of the Ri plasmid together with the tobacco pmt gene under the control of CaMV 35S promoter, into the genome of Datura metel and Hyoscyamus muticus. This gene codes for putrescine:SAM N-methyltransferase (PMT; EC. 2.1.1.53), which catalyses the first committed step in the tropane alkaloid pathway. Hairy root cultures overexpressing the pmt gene aged faster and accumulated higher amounts of tropane alkaloids than control hairy roots. Both hyoscyamine and scopolamine production were improved in hairy root cultures of D. metel, whereas in H. muticus only hyoscyamine contents were increased by pmt gene overexpression. These roots have a high capacity to synthesize hyoscyamine, but their ability to convert it into scopolamine is very limited. The results indicate that the same biosynthetic pathway in two related plant species can be differently regulated, and overexpression of a given gene does not necessarily lead to a similar accumulation pattern of secondary metabolites.