A regional strategy to decrease the time to thrombectomy in patients with low probability of treatment by thrombolysis

BACKGROUND AND PURPOSE

The best transportation strategy for patients with suspected large vessel occlusion (LVO) is unknown. Here, we evaluated a new regional strategy of direct transportation to a Comprehensive Stroke Center (CSC) for patients with suspected LVO and low probability of receiving intravenous thrombolysis (IVT) at the nearest Primary Stroke Center (PSC).

METHODS

Patients could be directly transported to the CSC (bypass group) if they met our pre-hospital bypass criteria: high LVO probability (i.e., severe hemiplegia) with low IVT probability (contraindications) and/or travel time difference between CSC and PSC<15 minutes. The other patients were transported to the PSC according to a "drip-and-ship" strategy. Treatment time metrics were compared in patients with pre-hospital bypass criteria and confirmed LVO in the bypass and drip-and-ship groups.

RESULTS

In the bypass group (n=79), 54/79 (68.3%) patients met the bypass criteria and 29 (36.7%) had confirmed LVO. The positive predictive value of the hemiplegia criterion for LVO detection was 0.49. In the drip-and-ship group (n=457), 92/457 (20.1%) patients with confirmed LVO met our bypass criteria. Among the 121 patients with bypass criteria and confirmed LVO, direct routing decreased the time between symptom discovery and groin puncture by 55 minutes compared with the drip-and-ship strategy (325 vs. 229 minutes, P<0.001), without significantly increasing the time to IVT (P=0.19).

CONCLUSIONS

Our regional strategy led to the correct identification of LVO and a significant decrease of the time to mechanical thrombectomy, without increasing the time to IVT, and could be easily implemented in other territories.

Genotypic and phenotypic diversity of Lactobacillus rossiae isolated from beer

AIMS

Over the past few years, the lactic acid bacteria (LAB) species Lactobacillus rossiae has appeared on occasion as a beer spoiler, in addition to its role as an inhabitant of sourdough and other foods. Many authors have described the L. rossiae sourdough isolates as phenotypically and genotypically extremely versatile. This characterization was confirmed in a comprehensive genotypic and phenotypic study based on 11 beer-related L. rossiae isolates.

MATERIALS AND METHODS

The beer-related isolates and the L. rossiae type strain were classified in a polyphasic approach applying 16S rRNA, rpoA and pheS housekeeping gene sequence comparisons, DNA-DNA hybridization and rep-PCR technique. Additionally, carbohydrate fermentation and amino-acid metabolism were examined. In terms of the beer-spoilage ability, the growth in two different beer types was examined and the presence of three prominent hop resistance genes (horA, horC and hitA) and of one gene presumably responsible for the production of exopolysaccharides (gtf) was checked.

CONCLUSION

The carbohydrate fermentation pattern (GTG)₅ rep-PCR and the pheS gene sequence comparison showed deviations between sourdough and beer-related isolates. DNA-DNA hybridization values and the pheS gene sequence comparison between beer-related isolates point towards the need for expansion of the limits for species description.

SIGNIFICANCE AND IMPACT OF THE STUDY

Lactobacillus rossiae shows great phenotypic and genotypic variability stretching the limits of species description. The correlation between pheS gene sequence and the presence of the horC gene is important for brewing microbiologists and the search for beer-spoilage prediction methods.

Endovascular stent-based revascularization of malignant superior vena cava syndrome with concomitant implantation of a port device using a dual venous approach

PURPOSE

The aim of this paper is to evaluate the safety and efficacy of endovascular revascularization of malignant superior vena cava syndrome (SVCS) and simultaneous implantation of a totally implantable venous access port (TIVAP) using a dual venous approach.

MATERIALS AND METHODS

Retrospectively, 31 patients (mean age 67 ± 8 years) with malignant CVO who had undergone revascularization by implantation of a self-expanding stent into the superior vena cava (SVC) (Sinus XL®, OptiMed, Germany; n = 11 [Group1] and Protégé ™ EverFlex, Covidien, Ireland; n = 20 [Group 2]) via a transfemoral access were identified. Simultaneously, percutaneous access via a subclavian vein was used to (a) probe the lesion from above, (b) facilitate a through-and-through maneuver, and (c) implant a TIVAP. Primary endpoints with regard to the SVC syndrome were technical (residual stenosis < 30%) and clinical (relief of symptoms) success; with regard to TIVAP implantation technical success was defined as positioning of the functional catheter within the SVC. Secondary endpoints were complications as well as stent and TIVAP patency.

RESULTS

Technical and clinical success rate were 100% for revascularization of the SVS and 100% for implantation of the TIVAP. One access site hematoma (minor complication, day 2) and one port-catheter-associated sepsis (major complication, day 18) were identified. Mean catheter days were 313 ± 370 days. Mean imaging follow-up was 184 ± 172 days. Estimated patency rates at 3, 6, and 12 months were 100% in Group 1 and 84, 84, and 56% in Group 2 (p = 0.338).

CONCLUSION

Stent-based revascularization of malignant SVCS with concomitant implantation of a port device using a dual venous approach appears to be safe and effective.

Letrozole may be a valuable maintenance treatment in high-grade serous ovarian cancer patients

OBJECTIVES

Endocrine therapy is used as maintenance in estrogen receptor (ER) positive breast cancers and has been proposed in low-grade serous ovarian cancers (LGSOC). Here we examine a rationale for its use as maintenance in high-grade serous ovarian cancers (HGSOC).

METHODS

We accessed the TCGA PANCAN dataset to evaluate the expression of ESR1. ESR1 expression data on all cancers (n=8901) and HGSOC (n=527) were followed by investigation of ER expression via immunohistochemistry (IHC) (n=4071). The same was performed in an independent cohort for matched primary and recurrent HGSOC (n=80). Finally, newly diagnosed ER+ HGSOC patients were offered a maintenance therapy with Letrozole.

RESULTS

ESR1 was strongly expressed in similar levels in HGSOC as in breast cancer. We found a strong ER expression via IHC in both the primary and matched recurrent HGSOC, particularly in the Platinum-resistant subgroup. The additional use of Letrozole as maintenance treatment was associated with a significantly prolonged recurrence free interval (after 24months 60% when taking Letrozole versus 38.5% in the control group; p=0.035; RFS: IC₅₀ reached by one subject versus 13.2months). This effect was also present in patients treated additionally with Bevacizumab; 20.8% of patients had no recurrence after 12months compared to 87.5% when taking Letrozole in addition to Bevacizumab (p=0.026).

CONCLUSIONS

Primary HGSOC have a slightly higher ESR1 than and a similar ER expression breast cancer where aromatase inhibitor maintenance is routine for decades. Here we demonstrate evidence for the usefulness of Letrozole in HGSOC, particularly in patients with chemotherapy resistance or residual disease.

Hot spots become cold spots: coevolution in variable temperature environments

Antagonistic coevolution between hosts and parasites is a key process in the genesis and maintenance of biological diversity. Whereas coevolutionary dynamics show distinct patterns under favourable environmental conditions, the effects of more realistic, variable conditions are largely unknown. We investigated the impact of a fluctuating environment on antagonistic coevolution in experimental microcosms of Pseudomonas fluorescens SBW25 and lytic phage SBWΦ2. High-frequency temperature fluctuations caused no deviations from typical coevolutionary arms race dynamics. However, coevolution was stalled during periods of high temperature under intermediate- and low-frequency fluctuations, generating temporary coevolutionary cold spots. Temperature variation affected population density, providing evidence that eco-evolutionary feedbacks act through variable bacteria-phage encounter rates. Our study shows that environmental fluctuations can drive antagonistic species interactions into and out of coevolutionary cold and hot spots. Whether coevolution persists or stalls depends on the frequency of change and the environmental optima of both interacting players.

[Neoadjuvant chemotherapy in muscular invasive bladder cancer: Complications and consequences with cystectomy]

INTRODUCTION

The fear of the deterioration of the patient's condition related to the toxicity of neoadjuvant chemotherapy is a barrier to its development. This multicenter retrospective study aims to present the secondary effects of neoadjuvant chemotherapy and its impact on the achievement of cystectomy.

MATERIALS AND METHODS

Patients with urothelial carcinoma classified cT2 to cT4a N0M0 were included. Chemotherapy with 6 cycles of MVAC (methotrexate, vinblastine, adriamycin, and cisplatin) followed by a cysto-prostatectomy or anterior pelvectomy was scheduled.

RESULTS

A total 32 patients were included. Six cycles of neoadjuvant chemotherapy were performed in all 11 patients. Shutdown causes were toxicity in 85% of cases. Cystectomy was performed in 86.6% of patients. Surgery was not performed in 6 patients. The reasons were the alteration of the general condition in 2 cases, 2 patients had advanced cancers diagnosed intraoperatively, and 2 refused surgery. Complications of grades 3 and 4 according to the classification of Clavien and Dindo had occurred respectively in 15.3% and 11.5%.

DISCUSSION

This study reports results close to what is found in the literature on the effects of neoadjuvant chemotherapy on achieving cystectomy, but it has some limitations: the retrospective analysis of data on surgery and the lack of control group. In addition, the short follow-up does not yet allow to know the long-term oncological results.

CONCLUSION

This study supports the fact that the toxicity of neoadjuvant chemotherapy does not seem to cause a significant risk of non-completion of cystectomy.

LEVEL OF EVIDENCE

4.

324 TESTIS-SPECIFIC EXPRESSION OF Oct4-EGFP TRANSGENE IN PIG

Oct4 is a transcription factor essential for establishment and maintenance of pluripotency in mammalian stem cells. Oct4 expression was found in early embryos and germ cells throughout fetal development. In male mice, Oct4 expression is found in mitotically arrested prospermatogonia until birth. After onset of spermatogenesis, expression is maintained in type A spermatogonia, but is downregulated in type B spermatogonia and in spermatocytes (Pesce et al. 1998 Mech. Dev). Previously, we successfully generated Oct4-EGFP reporter pigs carrying the entire 18-kb genomic sequence of the murine Oct4 gene fused to the enhanced green fluorescent protein (EGFP) cDNA (Nowak-Imialek et al. 2011 Stem Cells Dev.). This animal model is unique because it allows in vivo and in vitro visualisation of Oct4-positive cells. Germ line specific Oct4-EGFP expression was analysed in testis isolated from young (<1 week) and adult (>7 months) pigs. Squash preparation of testicular tissue isolated from adult transgenic boars revealed high amounts of EGFP-positive cells compared to young piglets. We confirmed Oct4 and EGFP expression in the testis from young and adult transgenic animals using Northern blot analysis. Specific expression of Oct4 and EGFP in testis could be observed in blots as a single band of 1.5 kb. As a loading control, the blot was rehybridized with a β-actin probe. Mammalian testes contain different cell types, including germ cells, Sertoli cells, Leydig cells, and peritubular cells. To define the cellular origin of EGFP-expressing cells, we isolated these cells from adult transgenic testis using fluorescence-activated cell sorting (FACS)-based techniques. Analysis of isolated EGFP positive cells with qRT-PCR demonstrated the presence of marker genes specific for undifferentiated (Oct4, UTF1, FGFR3, PGP 9.5, THY-1, SALL4, and GFRα1) and differentiated (BOLL and PRM2) germ cells. Markers specific for Sertoli cells (vimentin) and Leydig cells (LHCGR) were not observed. To verify the localization of EGFP-positive cells in seminiferous tubules, we performed immunohistochemical detection of GFP in adult pig testis. Unlike the Oct4-EGFP reporter mouse model, GFP protein was not found in spermatogonia attached to the basement membrane of seminiferous tubules, but instead were found in differentiated germ cells, including spermatocytes and spermatids. These results show that the Oct4-EGFP expression in testis differs between mouse and porcine Oct4-EGFP transgenic models. To verify that the EGFP expression driven by the mouse Oct4 promoter in porcine testis reflects the endogenous Oct4 expression profile, Western blot and histochemical analyses are currently underway.

192 IDENTIFICATION AND CHARACTERIZATION OF Oct4-EGFP EXPRESSING CELLS IN TRANSGENIC PIG TESTIS

We have produced germ line transgenic pigs carrying the entire 18-kb genomic sequence of the murine Oct4 gene fused to the enhanced green fluorescent protein (EGFP) cDNA (OG2 construct; Nowak-Imialek et al., 2011 Stem Cells Dev.). Expression of the EGFP reporter construct is confined to germ line cells, the inner cell mass, and trophectoderm of blastocysts, and testicular germ cells, including putative spermatogonial stem cells (SSC). SSC are unique among stem cells because they can both self-renew and differentiate into spermatozoa. In-depth knowledge on porcine SSC has been hampered by the inability to isolate these cells from the complex cell population of the testis. In the Oct4-EGFP transgenic mouse, SSC are the only adult stem cells that express Oct4. Fluorescence microscopy of testicular tissue isolated from transgenic piglets revealed minimum numbers of EGFP-positive cells, whereas testicular tissue isolated from adult transgenic boars contained a high amount of EGFP fluorescent cells. Northern blot analysis confirmed stronger EGFP expression in the testis of adult transgenic pigs than in the testis from transgenic piglets. Time course and the signal intensity of EGFP expression in Oct4-EGFP testis paralleled mRNA expression of the endogenous Oct4 gene. Here, we used adult Oct4-EGFP transgenic pigs as a model for fluorescence-activated cell sorting (FACS)-based isolation of EGFP-expressing cells from testes. To obtain a single-cell suspension, the testes were enzymatically dissociated using two digestion steps. Thereafter, FACS based on EGFP expression was successfully used to purify specific testicular cell populations. Two cell populations, i.e. EGFP+ (14%) and EGFP– (45%) could be isolated. Subsequently, qualitative PCR analyses were performed on EGFP+, EGFP–, and unsorted cell populations using marker genes specific for pluripotency and undifferentiated germ cells (OCT4, FGFR3, UTF1, PGP9.5, GFRα1, CD90, SALL4), differentiating germ cells (c-KIT), meiosis (BOLL), spermatids (PRM2), and somatic cells (VIM, LHCGR). All of the genes, including OCT4, UTF1, FGFR3, PGP9.5, CD90, SALL4, and GFRα1 were expressed at least 3-fold and up to 12-fold greater in the EGFP-positive population. Vimentin, which is mainly expressed in Sertoli cells and LHCGR, which is mainly expressed in Leydig cells, were expressed in unsorted and EGFP– cell populations and at very low level in EGFP+ cells. Moreover, expression of the c-KIT and PRM2 markers were detected also in EGFP+ cell population, indicating that these cells contain also differentiating spermatogonia. To explore the characteristics of the Oct4-EGFP expressing cells in greater detail, localization in the porcine testis sections and analysis of co-expression with germ cell markers using immunohistochemistry is currently underway.

The genetics of teratocarcinoma transplantation: tumor formation in allogeneic hosts by the embryonal carcinoma cell lines F9 and PCC3

Two cultured lines of murine embryonal carcinoma, F9 and PCC3, have been grafted to a variety of allogeneic hosts. The host strains have been classified by their resistance or sensitivity to these carcinomas. Resistance seems to be immunological in nature.Allograft rejection does not correlate withH-2 haplotype, and seems to be controlled by a limited number of recessive factors, presumably histocompatibility genes. We infer that these factors have limited polymorphism in the mouse species. Recombinational analysis of strain A/He has revealed the presence of a recessive factor linked to theH-2 locus. Tumor resistance of strains C57BL/6 and AKR appears to result from the interaction of dominant or semi-dominant factors in theH-2 region with other recessive elements in the genetic background.Though F(1) hybrids between resistant mouse strains and the syngeneic strain 129 are largely tumor-sensitive, a low level of hybrid resistance to F9 has been observed and shown to be eliminated by X-irradiation.

Expression of embryonic characters by malignant cells

While the expression of fetal characters by malignant cells is now well-documented, the mechanism involved and the nature of the cells that are the target of malignant transformation remain controversial. It has often been assumed that carcinogenesis results in 'dedifferentiation' of specialized cells. The alternative hypothesis is that neoplasia results from a disorder of some normal stem cells. This view is discussed in relation to several examples, in particular teratocarcinomas.

Large-area electro-optic ZnTe terahertz emitters

We present a detailed experimental and theoretical study of terahertz (THz) generation and beam propagation in an optoelectronic THz system consisting of a large-area (ZnTe) electro-optic emitter and a standard electro-optic detector, and provide a comparison to typical biased GaAs emitters. As predicted by theory, in the absence of saturation the generated THz pulse energy is inversely proportional to the area of the optical pump beam incident on the emitter, although the detected on-axis electric field amplitude of the subsequently focused THz beam is practically independent of this area. This latter result promotes the use of larger emitter crystals in amplifier-laser-based THz systems in order to minimize saturation effects. Moreover, the generation of an initially larger THz beam also provides improved spatial resolution at intermediate foci between emitter and detector.

Cationic disorder, microstructure and dielectric response of ferroelectric SBT ceramics

Polycrystalline samples of SrBi2Ta2O9(acronym SBT) have been prepared by means of solid-state reaction either using a classical route or by mechanochemical activation. For each compound, a structural analysis of the ferroelectric orthorhombic phase (space groupA21am) has been performed from the fitting of neutron and/or X-ray powder diffraction data using the Rietveld method. A cationic disorder on Bi3+and Sr2+crystallographic sites has been revealed, the Sr atoms occupying the Bi sites andvice versa. From diffraction peak broadening analyses of high-resolution synchrotron X-ray diffraction data, it has been shown that the two grinding methods (manual or mechanical) induce local strains, the average apparent strain being three times larger for the mechanically ground sample. In order to link microstructure and ferroelectric properties, the dielectric constant has been measured as a function of the temperature. It appears that the position and the shape of the dielectric anomaly strongly depend upon the composition and the route used to elaborate the powders. More exactly, for the mechanically ground powder, the large apparent strain, probably correlated to the strong cation exchange revealed by the structural refinement, leads to a significantly enhanced dielectric response.

Complexity and tinkering

All recent results in the fields of development and evolution point to a role of regulatory circuits as a major cause of evolutionary changes.

Cytotoxicity assessment of latex urinary catheters on cultured human urothelial cells

PURPOSE

To study the toxicity of latex urinary catheters on cultured human urothelial cells (HUC).

MATERIALS AND METHODS

We exposed monolayers of HUC (well characterized for their proliferation, qualitative evaluation and quantitative measurement of cytokeratins) to either pure or diluted liquid latex extracts, obtained under standard conditions or by direct contact with materials.

RESULTS

The latex urinary catheter appears to be highly toxic since cell viability and metabolic activity were about 10% of those of negative controls for original extracts. Concerning direct contact, latex reduced cell viability, metabolic activity and cell proliferation of HUC on days 1, 3 and 8.

CONCLUSION

The high toxicity of latex on HUC is confirmed for extracts and direct contact. Therefore, it should no longer be used for urinary catheters.

Dietary management of feline chronic renal failure: where are we now? In what direction are we headed?

Dietary modification is of primary importance in managing cats with chronic renal failure. Diets designed for cats with chronic renal failure are typically formulated to be pH neutral and contain reduced quantities of protein, phosphorus and sodium and an increased quantity of potassium. These changes in diet formulation are designed to ameliorate clinical signs of renal failure by adapting dietary intakes to meet the limited ability of failing kidneys to adapt to the normal range of dietary intakes. Important recent clinical trials support the therapeutic value of dietary therapy in cats with chronic renal failure.

Laparoscopic radical prostatectomy: preliminary results

BACKGROUND

Retropubic and perineal radical prostatectomy are used for curative treatment of localized prostate cancer. More complex urological procedures are now being done with laparoscopy. We present our initial results of transperitoneal laparoscopic radical prostatectomy.

MATERIALS AND METHODS

Twenty laparoscopic radical prostatectomies were performed between May 1998 and May 1999. The mean age at the time of surgery was 64.2 years. There were 14 stage T1c, 5 stage T2a and 1 stage T2b tumors. The preoperative PSA was 9. 3 ng/ml (normal <4 ng/ml). The Gleason score for positive specimens in 6 random echo-guided endorectal biopsies was 5.7. Four trocars were used. Insufflation pressure was 15 mmHg. The seminal vesicles were first dissected. The prostate was dissected free from the anterior face of the rectum to the prostate apex. Then the peritoneum was incised to find the apex of the prostate. The puboprostatic ligaments were isolated and cut, and the dorsal vein complex was ligated and cut to expose the urethra. The bladder neck was opened and dissected free from the prostate. The lateral pedicles were coagulated before sectioning the urethra. The radical prostatectomy specimen was left along the sigmoid colon, the bladder neck was reconstructed, and a urethrovesical anastomosis was performed with 6 interrupted sutures. The prostatectomy specimen was removed intact in a sack by enlarging the umbilical trocar port. All the prostatectomy specimens were processed according to the Standford protocol. Prostate weight, tumor weight, the Gleason score, and the tumor status of the capsule, seminal vesicles, lymph nodes and surgical margins were studied.

RESULTS

The operating time was 385 min. Two patients were transfused. The mean hospital stay was 7. 8 days. The Foley catheter was removed 10.7 days after the operation. Specimen weight was 61 (28-126) g, the Gleason score was 5.9, and tumor volume was 1.4 ml. There were 18 stage pT2, 1 stage pTa (capsular effraction) and 1 stage pT3b (seminal vesicle invasion) tumors. There were four positive surgical margins (2 at the apex and 2 at the bladder neck). All the patients had a postoperative PSA level <0.1 ng/ml at 1 month. The first patient had urethrovesical anastomotic leakage, and required Foley catheterization for 21 days. There was 1 colostomy for rectal injury and 1 urinoma because of urethrovesical anastomotic leakage that required an open surgical procedure. One month after surgery, 15 (75%) patients were fully continent. Six patients had erections, and 5 stated having sexual intercourse.

CONCLUSION

These preliminary results show that radical prostatectomy can be performed laparoscopically. Laparoscopy offered excellent vision of all the anatomical structures of the pelvis, permitting precise dissection. Long-term follow-up and further studies are required to confirm and improve these results.

Analytical and prospective evaluation of urinary cytokeratin 19 fragment in bladder cancer

PURPOSE

We evaluated CYFRA 21-1, an immunoradiometric assay, developed to detect soluble cytokaratin 19 fragment, for its diagnostic performance in bladder transitional cell carcinoma as well as its analytical performance.

MATERIALS AND METHODS

We assessed CYFRA 21-1 in the serum and urine of 182 patients, including 66 with bladder transitional cell carcinoma (group 1), 66 with another urological pathology (group 2) and 50 free of urothelial disease (group 3). The power of urinary CYFRA as a diagnostic test for bladder transitional cell carcinoma was evaluated by receiver operating characteristics curve analysis. Analytical performance was assessed by determining intra-assay and interassay precision, and accuracy by dilution testing and recovery of supplemented analyte.

RESULTS

Mean urinary CYFRA plus or minus standard deviation was 154.39+/-49.00, 22.6+/-8.9 and 2.40+/-0.14 ng./ml. in groups 1 to 3, respectively (significantly different). Receiver operating characteristics curve analysis revealed optimal 96.9% sensitivity and 67.2% specificity for a threshold value of 4 ng./ml. Analytical determination showed that intra-assay and interassay precision provides a satisfactory coefficient of variation. The assay for accuracy had acceptable recovery in diluted samples as well as in those with supplemented analyte.

CONCLUSIONS

The urinary immunoradiometric CYFRA 21-1 assay performs well analytically. Urinary CYFRA 21-1 is a useful marker for diagnosing transitional cell carcinoma and provides sensitivity in low grade disease.

[Gynecomastia]

Gynaecomastia is the least rare manifestation of the male breast disease. Urologists must therefore be able to distinguish the various forms of gynaecomastia, eliminate a testicular tumour and identify the main causes by performing a simple but complete assessment. Medical treatment is fairly disappointing. Surgical treatment is required in patients presenting with complications or when persistent gynaecomastia is aesthetically bothersome.