Sentinel Lymph Node Mapping in Prostate Cancer:Magnetic Route

Purpose: Prostate cancer is the predominant cancer type among Western men. Despite the application of radical treatments, a notable recurrence risk is linked to metastatic lymph nodes (LNs) beyond the standard resection area. Consequently, the concept of sentinel LN biopsy (SLNB) was introduced to pinpoint LNs draining from the primary tumor. The magnetic nanoparticles (MNPs) as a tracer facilitating SLNB hold promise for preoperative LN staging. Therefore, the primary objective of this pilot study was to explore the potential of MNPs in aiding preoperative LN staging and detecting perioperative LNs.Materials and Methods: One day before the surgery, patients received ultrasound-guided transrectal injection of a magnetic tracer. MRI was acquired 1 hour after the injection. Magnetic measurements were conducted using 2 handheld probes on the resected material, following laparoscopic radical prostatectomy. Follow-up MRI was acquired 12 weeks postsurgery.Results: Two of the 12 patients had histopathologic-confirmed metastatic lymph nodes. Magnetic detectors identified a total of 113 lymph nodes, with 105 containing magnetic tracer at histopathology. Both magnetic detectors exhibited similar performance. Preoperative MNP-enhanced MRI revealed 166 lymph nodes, with 104 within and 62 outside the extended pelvic lymph node dissection (ePLND) area. Postoperative MRI displayed 95 lymph nodes, with 48 within and 47 outside the ePLND.Conclusions: This pilot study has proven the feasibility of a thorough magnetic procedure, evaluating its essential components: tracer injection, dispersion of sentinel lymph nodes in the pelvic region, identification of lymph nodes by magnetic nanoparticle MNP-enhanced MRI, and magnetic lymph node detection using two distinct devices

Continence improvement after urethral preserving robot assisted laparoscopic prostatectomy

Incontinence is a common complication after robot assisted laparoscopic prostatectomy (RALP) that can have major impact on quality of life. Urethral preserving surgery could possibly reduce the risk of incontinence in this patient group. The aim of this study is to investigate the effect of the urethral preserving RALP technique (URALP) on incontinence rates. All conventional RALP and urethral preserving RALP were included in this study from May 2014 till January 2019. Continence was postoperatively observed after 6 weeks, 3, 6, 9 and 12 months and was defined as maximal use of 1 safety pad per day. After 6 weeks significantly more URALP patients were continent (82.1% URALP vs. 42.5% RALP, p &lt; 0.001), and this difference remained significant after 12 months (98.4% URALP vs. 87.5% RALP, p &lt; 0.001). Based on our promising findings we suggest incorporating the urethral preserving method as the first choice RALP technique to improve incontinence after RALP.</p

Ductoscopic Detection of Intraductal Lesions in Cases of Pathologic Nipple Discharge in Comparison with Standard Diagnostics: The German Multicenter Study

SummaryBackground: According to the literature, ductoscopy is gaining increasing importance in the diagnosis of intraductal anomalies in cases of pathologic nipple discharge. In a multicenter study, the impact of this method was assessed in comparison with that of standard diagnostics. Patients and Methods: Between 09/2006 and 05/2009, a total of 214 patients from 7 German breast centers were included. All patients underwent elective ductoscopy and subsequent ductal excision because of pathologic nipple discharge. Ductoscopy was compared with the following standard diagnostics: breast sonography, mammography, magnetic resonance imaging (MRI), galactography, cytologic nipple swab, and ductal lavage cytology. The histological and imaging results were compared and contrasted to the results obtained from the nipple swab and cytologic assessment. Results: Sonography had the highest (82.9%) sensitivity, followed by MRI (82.5%), galactography (81.3%), ductoscopy (71.2%), lavage cytology (57.8%), mammography (57.1%), and nipple swab (22.8%). Nipple swabs had the highest (85.5%) specificity, followed by lavage cytology (85.2%), ductoscopy (49.4%), galactography (44.4%), mammography (33.3%), sonography (17.9%), and MRI (11.8%). Conclusion: Currently, ductoscopy provides a direct intraoperative visualization of intraductal lesions. Sensitivity and specificity are similar to those of standard diagnostics. The technique supports selective duct excision, in contrast to the unselective technique according to Urban. Therefore, ductoscopy extends the interventional/diagnostic armamentarium

The effect of office based flexible and rigid cystoscopy on pain experience in female patients

Purpose: Rigid and flexible cystoscopies are both routinely used in female patients. Literature is conflicting whether flexible cystoscopy is less painful compared to rigid cystoscopy. The aim of this study was therefore to investigate whether using flexible cystoscopy leads to less discomfort and pain compared to rigid cystoscopy in female patients who underwent first time cystoscopy. Materials and Methods: One hundred eighty-nine female patients, who never had undergone cystoscopy, were randomized into 2 groups: 92 patients underwent rigid cystoscopy and 97 patients flexible cystoscopy. Directly after the cystoscopy procedure all patients were asked to fill out their pain experience on a 100-mm visual analogue pain scale (VAS). Results: Median VAS score was significantly lower for women undergoing flexible cystoscopy (0 [0–20]) compared to rigid cystoscopy (15 [0–38], p<0.001). In addition, age was inversely associated with VAS score, indicating that younger females experienced more pain (R=−0.30, p=0.001). The use of flexible cystoscopy was associated with a decrease in VAS score and remained significant after adjustment for age, sex of urologist, performing urologist and indication (standardized β =−0.17, p=0.048). Conclusions: The use of flexible cystoscopy resulted in a significantly lower pain experience compared to rigid cystoscopy. Based on patient’s pain experience during cystoscopy, this study implicates to use flexible cystoscopy in female patients who undergo first time cystoscopy

Development of a Direct in vitro Plant Regeneration Protocol From Cannabis sativa L. Seedling Explants: Developmental Morphology of Shoot Regeneration and Ploidy Level of Regenerated Plants

[EN] In vitro shoot regeneration can efficiently contribute to the improvement of recalcitrant Cannabis sativa L. We aimed at developing a highly efficient protocol for in vitro direct regeneration of C. sativa plants from different explants (cotyledon, hypocotyl, and true leaf) from seedlings of monoecious C. sativa short-day varieties Ferimon, Felina32, Fedora17, and USO31, together with dioecious neutral-day variety Finola. Ten regeneration media, including already published protocols, and self-designed combinations of plant growth regulators were tested. The developmental morphology since germination of seeds to the development of rooted plantlets was followed. Additionally, the ploidy level of explants and in vitro regenerants was analyzed. We concluded that hypocotyl is the best explant for in vitro direct regeneration of C. sativa plants with 49.45% of responding explants, while cotyledon and true leaf had a poor response with, respectively, 4.70 and 0.42% of explants developing plantlets. In terms of shoot regeneration, we found significant differences among the culture media evaluated and the varieties studied. Overall, the best regeneration media were ZEARIB 2.0 (mg/L) and ZEARIB 1.0 (mg/L) C NAA 0.02 (mg/L) with 66.67% of responding hypocotyls. Amazingly, hypocotyls cultured in medium without plant growth regulators showed an excellent response (61.54% of responding hypocotyls) and spontaneous rooting of regenerants (17.94%). In vitro regenerated plants were acclimatized just 6 weeks after culture initiation. The developmental morphology study suggests that regenerated shoots originate from pericycle cells adjacent to xylem poles. Polysomaty was detected in hypocotyls and cotyledons of all varieties studied, and diploid (>80%) and mixoploid (with diploid and tetraploid cells) plants were regenerated. Our protocol allows a high shoot organogenesis efficiency in different C. sativa varieties. The fact that a significant percentage of plants are mixoploid may provide an alternative way to develop polyploids in C. sativa. Our results show that direct in vitro regeneration may make a significant contribution to the development of improved C. sativa materials for medical applications.Galán-Ávila, A.; García-Fortea, E.; Prohens Tomás, J.; Herraiz García, FJ. (2020). Development of a Direct in vitro Plant Regeneration Protocol From Cannabis sativa L. Seedling Explants: Developmental Morphology of Shoot Regeneration and Ploidy Level of Regenerated Plants. Frontiers in Plant Science. 11:1-15. https://doi.org/10.3389/fpls.2020.00645S11511Adelberg, J. W., Rhodes, B. B., & Skorupska, H. T. (1993). 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Phage therapy as an approach to prevent Vibrio anguillarum infections in fish larvae production

Fish larvae in aquaculture have high mortality rates due to pathogenic bacteria, especially the Vibrio species, and ineffective prophylactic strategies. Vaccination is not feasible in larvae and antibiotics have reduced efficacy against multidrug resistant bacteria. A novel approach to controlling Vibrio infections in aquaculture is needed. The potential of phage therapy to combat vibriosis in fish larvae production has not yet been examined. We describe the isolation and characterization of two bacteriophages capable of infecting pathogenic Vibrio and their application to prevent bacterial infection in fish larvae. Two groups of zebrafish larvae were infected with V. anguillarum (∼106 CFU mL-1) and one was later treated with a phage lysate (∼108 PFU mL-1). A third group was only added with phages. A fourth group received neither bacteria nor phages (fish control). Larvae mortality, after 72 h, in the infected and treated group was similar to normal levels and significantly lower than that of the infected but not treated group, indicating that phage treatment was effective. Thus, directly supplying phages to the culture water could be an effective and inexpensive approach toward reducing the negative impact of vibriosis in larviculture

Metallkatalysierte Hydrogenolyse von biogenen Butandiolen

The hydrogenolysis of butanediols was investigated and heterogeneous noble metal catalysts were synthesized for this reaction. Based on the model reaction of 2,3-butanediol to 2-butanol, the commercially available catalyst ruthenium on carbon (Ru/C) was used to determine reaction parameters that allowed a kinetic analysis of the system without the influence of mass-transfer limitations. Subsequently, a kinetic investigation of the dehydration/hydrogenation sequence leading to the desired product 2-butanol was performed. In addition to the rate constants, the reaction enthalpy was determined using the Eyring–Polanyi equation. The substrate scope was then expanded to include 1,2-, 1,3-, and 1,4-butanediol. In contrast to 2,3-butanediol, those substrates favored the C-C-bond cleavage by decarbonylation, leading to the various isomers of propanol. Additionally, in the case of 1,3-butanediol it was possible to strongly influence the selectivity of the hydrogenolysis by changing the metal component of the catalyst to nickel or copper. For 1,4-butanediol, cyclodehydration to tetrahydrofuran occurred in addition to the decarbonylation but could be suppressed by using a basic support material such as ceria. For the decarbonylation of the three additional butanediols, a kinetic analysis was also performed, as well as a reaction network analysis of all four butanediols. Deuteration experiments allowed the investigation of the reactivity of the different positions on the carbon chain. The experiments showed that the terminal positions possess a higher reactivity than the internal positions, and carbon atoms bearing a hydroxyl substituent are considerably more reactive than unsubstituted ones. The second part of this work was focused on the development of ruthenium catalysts for the hydrogenolysis, once again using 2,3-butanediol as a model substrate. Different classes of support materials were investigated. Carbon-based materials such as activated carbons, covalent triazine frameworks, and carbon nanotubes showed mostly low activities as well as low selectivities to the target product 2-butanol. Moreover, several of them suffered from leaching of the catalytically active species during the reaction. Another group of support materials that were investigated are oxides. Acidic oxides such as alumina, silica, or zirconia afforded moderate conversions but led to the formation of side products. Basic oxides such as hydrotalcites were virtually inactive and mainly promoted the retro-aldol reaction. Only the catalyst based on amphoteric ceria showed high activity as well as ca. 80% selectivity to 2-butanol, and consequently an improved performance compared to the commercially available Ru/C. Therefore, Ru/CeO2 was characterized using TPD, DRIFTS, TPR, and TEM to reach an insight into structure–activity relations. The good performance of the catalyst likely depends on two factors. One is the special interaction between support and metal species, the other a combination of basic and weakly acidic centers on the surface of the support material. For Ru/CeO2, a kinetic analysis was performed as well as recycling experiments to investigate the long-term stability of the catalytic system. In these experiments, Ru/CeO2 demonstrated good stability over several runs, which in addition to its high activity and selectivity makes it a promising catalyst for hydrogenolysis