Retrograde Research Articles

Fission-independent compartmentalization of mitochondria during budding yeast cell division.

Lateral diffusion barriers compartmentalize membranes to generate polarity or asymmetrically partition membrane-associated macromolecules. Budding yeasts assemble such barriers in the endoplasmic reticulum (ER) and the outer nuclear envelope at the bud neck to retain aging factors in the mother cell and generate naïve and rejuvenated daughter cells. However, little is known about whether other organelles are similarly compartmentalized. Here, we show that the membranes of mitochondria are laterally compartmentalized at the bud neck and near the cell poles. The barriers in the inner mitochondrial membrane are constitutive, whereas those in the outer membrane form in response to stresses. The strength of mitochondrial diffusion barriers is regulated positively by spatial cues from the septin axis and negatively by retrograde (RTG) signaling. These data indicate that mitochondria are compartmentalized in a fission-independent manner. We propose that these diffusion barriers promote mitochondrial polarity and contribute to mitochondrial quality control.

Assessment of knee pain and knee range of motion (ROM) in distal third femur shaft fractures managed with retrograde (RG) intramedullary locking nail: A Retrospective study.

Objective: To assess knee pain and ROM in distal third femoral Fracture managed with RG intramedullary nailing technique. Study Design: Retrospective study. Setting: Ghurki Trust Teaching Hospital, Lahore. Period: November 2020 to March 2021. Material & Methods: 38 patients with extra-articular distal femoral Fracture were surgically treated in our center with an RG IM nail. The functional Outcome of the knee for knee pain and knee ROM was assessed using a modified Hospital for Special Surgery (HSS) Knee Score. Results: In this study, a total of 38 patients were diagnosed with distal third femur shaft fractures managed with retrograde (RG) intramedullary locking nail; among these, 31(81.6%) were males, and 7(18.4%) were females. The mean age of patients was 29.76±11.87, ranging from (16-50) years. In more than half of the cases, 30(78.9%) had a history of injury as RTA and 8(21.1%) sustained fall. The right side effected 65.8% of cases compared to the left side. 60.53% of cases had excellent functional Outcomes due to HSS sore between 85-100, 7.89% had good Outcomes because of scores ranging from 70-84, 26.32 had fair, and 5.285 had poor outcomes, respectively. There was no case with extension lag. Conclusion: Based on this study, RG IM nail fixation of distal extra-articular femur fracture can be safely performed, and improved knee function score can be anticipated with meticulous patient selection and adherence to proper postoperative physical therapy protocol.

Inactivation of HAP4 Accelerates RTG-Dependent Osmoadaptation in Saccharomyces cerevisiae.

Mitochondrial RTG (an acronym for ReTroGrade) signaling plays a cytoprotective role under various intracellular or environmental stresses. We have previously shown its contribution to osmoadaptation and capacity to sustain mitochondrial respiration in yeast. Here, we studied the interplay between RTG2, the main positive regulator of the RTG pathway, and HAP4, encoding the catalytic subunit of the Hap2-5 complex required for the expression of many mitochondrial proteins that function in the tricarboxylic acid (TCA) cycle and electron transport, upon osmotic stress. Cell growth features, mitochondrial respiratory competence, retrograde signaling activation, and TCA cycle gene expression were comparatively evaluated in wild type and mutant cells in the presence and in the absence of salt stress. We showed that the inactivation of HAP4 improved the kinetics of osmoadaptation by eliciting both the activation of retrograde signaling and the upregulation of three TCA cycle genes: citrate synthase 1 (CIT1), aconitase 1 (ACO1), and isocitrate dehydrogenase 1 (IDH1). Interestingly, their increased expression was mostly dependent on RTG2. Impaired respiratory competence in the HAP4 mutant does not affect its faster adaptive response to stress. These findings indicate that the involvement of the RTG pathway in osmostress is fostered in a cellular context of constitutively reduced respiratory capacity. Moreover, it is evident that the RTG pathway mediates peroxisomes-mitochondria communication by modulating the metabolic function of mitochondria in osmoadaptation.

P78 AN ANTEGRADE RECANALIZATION OF LEFT ANTERIOR DESCENDING CHRONIC TOTAL OCCLUSION WITH ORBITAL ATHERECTOMY IN PATIENT WITH SEVER LEFT VENTRICULAR DISFUNCTION

Abstract We share the case of a 71–year old man, affected by hypertension, presented in Emergency Room (ER) with chest pain. No clinical evidence of heart failure. EKG showed fast atrial fibrillation with QS complex and ST elevation in precordial leads. Echocardiogram confirmed sept and apex akinesia. Troponin I peak was 72pg/ml. In ER electrical cardioversion was efficacy performed. He was referred for invasive coronary angiography, that showed a left anterior descending (LAD) chronic total occlusion (CTO), with Rentrop grade 2 collaterals providing retrograde flow from the right coronary artery (RCA), a severe stenosis of ramus intermedius (RI) and a moderate stenosis of circumflex. A stress–echocardiogram demonstrated vitality of medio–basal anterior wall. Subsequent, recanalization procedure of LAD CTO was planned. J–CTO score was 1 (tapered calcific, lesion, <20mm). double radial access and ante grade approach was chosen. An EBU3.5 guiding catheter was engaged in the left coronary artery, and 8000 units of heparin administered. The iFR of Cx was 0.99, indicative of non significant myocardial ischemia. During hemodynamic evaluation of RI, a ventricular fibrillation occurred, treated by DC–SHOCK and PCI with stenting with no polymer, eluted with Biolimus A9 (3.0x24mm) with good result. The occlusion was crossed via an antegrade approach with an Asahi Gaia II wire and with microcatheter support. Gaia II was changed in favor of Asai Sion blu, and the IVUS catheter was enable of cross the lesion. Efficacy orbital atherectomy with Diamondback 260 was performed (5 ante and retro grade run at 80Krpm and a retro grade run at 120 Krpm. Ivus was able to cross the lesion. Efficacy pre–dilatation with semi and non compliant balloon (2.5–3.5mm) was performed and then stented with a 3.0 × 36 mm Bioloimu A9–eluting stent. Finally, IVUS confirmed correct stent expansion, achieving an excellent angiographic result. Patient was discharged with triple anti–thrombotic therapy, with indication to “life jacket” till the assessment at 1 month.

Vascular Access Flow during Dialysis: Does Needle Orientation Matter?

Background: Monitoring of vascular access outflow (VAO) in dialysis is based on the indicator dilution method by ultrasound (UD). The role of arterial needle orientation in VAO measurement is not clear. We compared the impact of the retrograde (RET) versus the antegrade orientation (ANT) in terms of (a) VAO (UD) and (b) dialysis adequacy. Moreover, we compared VAO (UD ANT and RET orientation) with VAO measured by Doppler ultrasound. Methods: 22 patients participated in the study. Inclusion criteria: Dialysis > 6 months with a functioning AVF, no stenosis, no active infection, EF > 45% and informed consent. 4 flow measurements were taken on the same dialysis day (4 consecutive weeks). To account for blood pressure variation, we “corrected” VAO for a mean arterial pressure of 100 mmHg. Doppler VAO was measured just before dialysis. Means were compared by the paired t-test. For correlation and agreement, linear regression and Bland-Altman analysis were performed respectively. Results: Mean VAO (UD) was higher in the (ANT) versus the (RET) orientation: 1286.17 mL/min (SD = 455.78, 95%CI = 1084–1488) versus 1189.96 mL/min (SD = 401.05, 95%CI = 1012–1368) (p = 0.013) with a mean difference of 96.21 mL/min (5.66%). Mean Kt/V (RET orientation) was 1.57 (SD = 0.10, 95%CI = 1.52–1.61) versus 1,55 (SD = 0.10, 95%CI = 1.50–1.60) (ANT) orientation (p = 0.062). Recirculation was always 0%. The mean VAO (Doppler) was 1079.54 mL/min (SD = 356.04, 95%CI = 922–1237), 16% lower than VAO measured by UD with (ANT) orientation (p = 0.009) and 9.3% lower than the VAO in the (RET) orientation (p = 0.113). Linear regression analysis showed that VA flows (ANT versus RET) orientation of the needle correlates well between them (r = 0.93, p < 0.001) but show poor agreement (Bland–Altman analysis). Conclusion: VAO (UD) in the RET orientation was significantly lower than VAO in the ANT orientation and more consistent with VAO assessed by Doppler without influencing dialysis adequacy. Therefore, when using UD for VAO surveillance, the RET orientation should be used.

Mitochondrial Retrograde Signaling Contributes to Metabolic Differentiation in Yeast Colonies.

During development of yeast colonies, various cell subpopulations form, which differ in their properties and specifically localize within the structure. Three branches of mitochondrial retrograde (RTG) signaling play a role in colony development and differentiation, each of them activating the production of specific markers in different cell types. Here, aiming to identify proteins and processes controlled by the RTG pathway, we analyzed proteomes of individual cell subpopulations from colonies of strains, mutated in genes of the RTG pathway. Resulting data, along with microscopic analyses revealed that the RTG pathway predominantly regulates processes in U cells, long-lived cells with unique properties, which are localized in upper colony regions. Rtg proteins therein activate processes leading to amino acid biosynthesis, including transport of metabolic intermediates between compartments, but also repress expression of mitochondrial ribosome components, thus possibly contributing to reduced mitochondrial translation in U cells. The results reveal the RTG pathway’s role in activating metabolic processes, important in U cell adaptation to altered nutritional conditions. They also point to the important role of Rtg regulators in repressing mitochondrial activity in U cells.

Influence of normograde versus retrograde catheterization of bile ducts in dogs treated for gallbladder mucocele.

To determine the influence of normograde (NG) versus retrograde (RG) catheterization of the cystic duct and common bile duct (CBD) in dogs with gallbladder mucoceles (GBM) treated with open cholecystectomy. Retrospective study. Dogs (n = 117) with GBM. Medical records were reviewed for signalment, history, clinical laboratory and diagnostic imaging findings, details of surgery including catheterization method, complications, and outcome. Long-term follow-up data were obtained by telephone or electronic communication. Relationships between catheterization method and clinical variables and outcome were evaluated. Dogs catheterized RG were more likely to experience any postoperative complication (p = .0004) including persistence of gastrointestinal signs (p = .0003). Survival to discharge and long-term survival did not differ by group (p = .23 and p = .49). Total bilirubin (TB) decreased by 70.3% after NG catheterization compared to 39.1% after RG catheterization (p = .03) and increased in 14.9% dogs catheterized NG and 38.0% dogs catheterized RG (p = .004). The presence of a diplomate surgeon at surgery resulted in decreased incidences of any perioperative or postoperative complication (p = .003 and p = .05). Retrograde catheterization was associated with more postoperative concerns than NG catheterization, but similar survival times. Surgery should be performed by diplomates experienced in biliary surgery to minimize complications. Although both NG and RG techniques to catheterize the cystic duct and CBD are options for treatment of GBM with low mortality, results of this study provide some evidence to recommend NG over RG catheterization.

The perplexity of catheter-directed thrombolysis for deep venous thrombosis: the approaches play an important role.

The recent adjunctive catheter-directed thrombolysis (ATTRACT) trial rose a controversy about the treatment effect of catheter-directed thrombolysis (CDT) in deep venous thrombosis (DVT). In fact, most studies including the ATTRACT trial did not perform subgroup analysis of catheterization approaches. Different approaches would confound the conclusions. Therefore, a single-center retrospective analysis was performed to compare the differences between the antegrade (AGA) and retrograde (RGA) approaches. Total 217 DVT patients treated with CDT were enrolled from January 2010 to December 2017, with mean age of 55.3years (67 received antegrade approach, 150 received retrograde approach). The clot burden reduction by segment was evaluated. The mean access establishment time and thrombolytic time were compared. The patency of the iliofemoral vein at 6months was evaluated. The rate of PTS, quality of life and venous insufficiency were assessed at 1year. AGA group showed better thrombolytic effect in popliteal and femoral vein than RGA group. The rate of iliofemoral clot burden reduction in RGA group was mostly at Grade II, while most were at Grade III in AGA group. The retrograde approach showed better thrombolysis effect in iliofemoral DVT than popliteal to iliac DVT. The RGA group reported longer mean access establishment time (5.4 ± 1.8 vs 27.0 ± 7.5min, p < 0.001) and thrombolytic time (6.9 ± 1.5 days vs 6.8 ± 1.5 days, p = 0.586). At 6months, RGA group had a lower rate of femoral vein patency (52.0% vs 89.6%, p < 0.001) and a higher rate of venous insufficiency (52.0% vs 29.9%, p < 0.001), compared with AGA group. Although there was no difference in the rate of PTS, the RGA group showed higher Villalta scores in the free and mild PTS. The antegrade approach was preferably recommended over the retrograde approach for CDT treatment.

Extension of Cellular Lifespan by Methionine Restriction Involves Alterations in Central Carbon Metabolism and Is Mitophagy-Dependent.

Methionine restriction (MR) is one of only a few dietary manipulations known to robustly extend healthspan in mammals. For example, rodents fed a methionine-restricted diet are up to 45% longer-lived than control-fed animals. Tantalizingly, ongoing studies suggest that humans could enjoy similar benefits from this intervention. While the benefits of MR are likely due, at least in part, to improved cellular stress tolerance, it remains to be determined exactly how MR extends organismal healthspan. In previous work, we made use of the yeast chronological lifespan (CLS) assay to model the extension of cellular lifespan conferred by MR and explore the genetic requirements for this extension. In these studies, we demonstrated that both dietary MR (D-MR) and genetic MR (G-MR) (i.e., impairment of the cell’s methionine biosynthetic machinery) significantly extend the CLS of yeast. This extension was found to require the mitochondria-to-nucleus retrograde (RTG) stress signaling pathway, and was associated with a multitude of gene expression changes, a significant proportion of which was also dependent on RTG signaling. Here, we show work aimed at understanding how a subset of the observed expression changes are causally related to MR-dependent CLS extension. Specifically, we find that multiple autophagy-related genes are upregulated by MR, likely resulting in an increased autophagic capacity. Consistent with activated autophagy being important for the benefits of MR, we also find that loss of any of several core autophagy factors abrogates the extended CLS observed for methionine-restricted cells. In addition, epistasis analyses provide further evidence that autophagy activation underlies the benefits of MR to yeast. Strikingly, of the many types of selective autophagy known, our data clearly demonstrate that MR-mediated CLS extension requires only the autophagic recycling of mitochondria (i.e., mitophagy). Indeed, we find that functional mitochondria are required for the full benefit of MR to CLS. Finally, we observe substantial alterations in carbon metabolism for cells undergoing MR, and provide evidence that such changes are directly responsible for the extended lifespan of methionine-restricted yeast. In total, our data indicate that MR produces changes in carbon metabolism that, together with the oxidative metabolism of mitochondria, result in extended cellular lifespan.

Retrograde signaling disruption influences ABC superfamily transporter, ergosterol and chitin levels along with biofilm formation in Candida albicans

ObjectiveThe rise in fungal infections is alarming due to emergence of multidrug drug resistance (MDR). Hence elucidating novel drug targets to circumvent the problem of MDR warrants immediate attention. This study analyzes the effect of retrograde (RTG) signaling disruption on major MDR mechanisms and virulence of the human pathogenic fungal species Candida albicans. Material and methodsDrug transporter activity was measured by rhodamine 6G (R6G) efflux. Membrane damage was studied by propidium iodide intake and ergosterol level determination. Cell wall effect was estimated by quantifying chitin levels and cell sedimentation rate. Biofilm formation was visualized by calcoflour white and crystal violet staining and measured by dry mass and MTT assay. Cell adherence to buccal epithelial cell was determined by trypan blue staining and MTT assay. Virulence was studied using nematode model Caenorhabditis elegans. ResultWe demonstrated that mutant of transcription factor CaRTG3 leads to impaired efflux activity of ATP Binding Cassette (ABC) superfamily multidrug transporters. We further uncover that rtg3 mutant exhibited a disrupted membrane, decreased ergosterol levels and increased chitin content. Furthermore, RTG signaling disruption leads to inhibited biofilm formation and cell adherence to buccal epithelial cells. Lastly, rtg3 mutant displayed a reduced infectivity in C. elegans illustrating its vulnerability as antifungal target. Interestingly, all the abrogated phenotypes could be rescued in the revertant strain of rtg3 mutant. ConclusionPresent study establishes a link between RTG signaling, drug efflux and biofilm formation and validates CaRTG3 as antifungal target. Intricate studies are needed to further understand and exploit this therapeutic opportunity.

Using Continuous And Interval Exercise To Manipulate Shear Rate Patterns In The Common Femoral Artery

Vascular shear rate (SR) assessed via ultrasound represents frictional force of blood flowing over the endothelium. Low and oscillatory shear confers a pro-inflammatory phenotype, whereas greater shear has an anti-inflammatory phenotype decreasing CVD risk. Exercise increases SR, however the impact of continuous (CON) and interval (INT) exercise upon the balance of anterograde (ANT) and retrograde (RET) SR and thus the oscillatory shear index (OSI) is unknown. PURPOSE: To examine the impact of acute CON and INT (no active recovery) exercise on SR patterns and OSI in the common femoral artery (CFA) during exercise. METHODS: 10 healthy individuals (25±3 years, n=5 male) underwent two work-matched exercise sessions (CON and INT) on a supine cycle ergometer at 125% lactate threshold. In each protocol repetitive ultrasound scans were taken of the CFA during a brief cessation in exercise to determine in-exercise shears. Flow mediated dilatation (FMD) was measured before and after exercise to assess acute changes in endothelial function. RESULTS: FMD did not differ after exercise in either protocol (CON: 9.9±8.1% vs 8.4±6.2%; INT: 9.1±5.9% vs 6.6±3.4%: P>0.05). ANT and RET SR reached a plateau in each protocol. Total ANT SR was lower in CON than INT (CON: 861540±291534 vs INT: 1955615±674594 s-1: P<0.05), however total RET SR did not differ between protocols (CON: 76625±89390 vs INT: 78126±78697 s-1: P>0.05). Peak and mean SR were similar in CON and INT, respectively (peak ANT: 1258±403 vs 1480±510 s-1; RET: 107±123 vs 108±75 s-1: P>0.05; meanANT: 1171±372 vs 1358±469 s-1; RET: 61±81 vs 54±55 s-1: P>0.05). Mean and peak OSI were also similar in both types of exercise (peak CON: 0.07±0.08 vs INT: 0.08±0.0.06 AU; mean CON: 0.05±0.06 vs INT: 0.04±0.04 AU; P>0.05). No time was spent in pure oscillatory shear (>0.5 AU). CONCLUSION: During exercise matched for intensity and the duration of muscular work, using an INT approach ensured a similar OSI but a greater total ANT SR compared to CON. This would suggest that in the exercising limb INT exercise does not confer a negative oscillatory profile. GRANT FUNDING: Medical Research Council

Tu1050 ANTEGRADE VERSUS RETROGRADE SINGLE BALLOON ENTEROSCOPY- IS THERE A DIFFERENCE IN PERFORMANCE?

Single balloon enteroscopy (SBE) is a widely used method of examining the portion of small bowel where conventional upper endoscopy and colonoscopy fail to reach. There are 2 major approaches of single balloon enteroscopy- through mouth or ante-grade approach (AG) or through anus or retrograde (RG)approach. Aim of this study was to assess the differences in performance and complications of both these approaches.

Filamentation Regulatory Pathways Control Adhesion-Dependent Surface Responses in Yeast.

Signaling pathways can regulate biological responses by the transcriptional regulation of target genes. In yeast, multiple signaling pathways control filamentous growth, a morphogenetic response that occurs in many species including fungal pathogens. Here, we examine the role of signaling pathways that control filamentous growth in regulating adhesion-dependent surface responses, including mat formation and colony patterning. Expression profiling and mutant phenotype analysis showed that the major pathways that regulate filamentous growth [filamentous growth MAPK (fMAPK), RAS, retrograde (RTG), RIM101, RPD3, ELP, SNF1, and PHO85] also regulated mat formation and colony patterning. The chromatin remodeling complex, SAGA, also regulated these responses. We also show that the RAS and RTG pathways coregulated a common set of target genes, and that SAGA regulated target genes known to be controlled by the fMAPK, RAS, and RTG pathways. Analysis of surface growth-specific targets identified genes that respond to low oxygen, high temperature, and desiccation stresses. We also explore the question of why cells make adhesive contacts in colonies. Cell adhesion contacts mediated by the coregulated target and adhesion molecule, Flo11p, deterred entry into colonies by macroscopic predators and impacted colony temperature regulation. The identification of new regulators (e.g., SAGA), and targets of surface growth in yeast may provide insights into fungal pathogenesis in settings where surface growth and adhesion contributes to virulence.

The Goldilocks effect of respiration on canavanine tolerance in Saccharomyces cerevisiae.

When glucose is available, Saccharomyces cerevisiae prefers fermentation to respiration. In fact, it can live without respiration at all. Here, we study the role of respiration in stress tolerance in yeast. We found that colony growth of respiratory-deficient yeast (petite) is greatly inhibited by canavanine, the toxic analog of arginine that causes proteotoxic stress. We found lower amounts of the amino acids involved in arginine biosynthesis in petites compared with WT. This finding may be explained by the fact that petite cells exposed to canavanine show reduction in the efficiency of targeting of proteins required for arginine biosynthesis. The retrograde (RTG) pathway signals mitochondrial stress. It positively controls production of arginine precursors. We show that canavanine abrogates RTG signaling especially in petite cells, and mutants in the RTG pathway are extremely sensitive to canavanine. We suggest that petite cells are naturally ineffective in production of some amino acids; combination of this fact with the effect of canavanine on the RTG pathway is the simplest explanation why petite cells are inhibited by canavanine. Surprisingly, we found that canavanine greatly inhibits colony formation when WT cells are forced to respire. Our research proposes a novel connection between respiration and proteotoxic stress.

Cardiolipin-deficient cells depend on anaplerotic pathways to ameliorate defective TCA cycle function

Previous studies have shown that the cardiolipin (CL)-deficient yeast mutant, crd1Δ, has decreased levels of acetyl-CoA and decreased activities of the TCA cycle enzymes aconitase and succinate dehydrogenase. These biochemical phenotypes are expected to lead to defective TCA cycle function. In this study, we report that signaling and anaplerotic metabolic pathways that supplement defects in the TCA cycle are essential in crd1Δ mutant cells. The crd1Δ mutant is synthetically lethal with mutants in the TCA cycle, retrograde (RTG) pathway, glyoxylate cycle, and pyruvate carboxylase 1. Glutamate levels were decreased, and the mutant exhibited glutamate auxotrophy. Glyoxylate cycle genes were up-regulated, and the levels of glyoxylate metabolites succinate and citrate were increased in crd1Δ. Import of acetyl-CoA from the cytosol into mitochondria is essential in crd1Δ, as deletion of the carnitine-acetylcarnitine translocase led to lethality in the CL mutant. β-oxidation was functional in the mutant, and oleate supplementation rescued growth defects. These findings suggest that TCA cycle deficiency caused by the absence of CL necessitates activation of anaplerotic pathways to replenish acetyl-CoA and TCA cycle intermediates. Implications for Barth syndrome, a genetic disorder of CL metabolism, are discussed.

Antegrade versus Retrograde Single Balloon Enteroscopy - Which Is Better?

Introduction: There are 2 major approaches of single balloon enteroscopy- through mouth or ante-grade approach (AG), or through anus or retrograde (RG)approach. Aim of this study was to assess the differences in performance and complications of both these approaches. Methods: A retrospective cohort study was conducted using a registry of consecutive cases of single balloon enteroscopy at the Cleveland Clinic over 8 years from January 1, 2008- December 31,2016. Electronic medical records were utilized to collect variables including patient demographic, status of antiplatelet agents (at time of procedure), and coexisting comorbid diseases (cardiovascular, renal, and hepatic). Data on endoscopic findings, intervention (if received) was also obtained. Performance of procedures was assessed on the basis of scope time (in minutes), extent reached and need for repeat procedures within 30 days. Numerical values were assigned based on the depth of scope insertion to assess extent reached: 1 = unable to reach small bowel, 2 = proximal jejunum for ante-grade and distal ileum for retro-grade, 3 = mid jejunum for ante-grade and mid ileum for retro-grade, and 4 = distal jejunum for ante-grade and proximal ileum for retro-grade studies. Results: Of 510 patients who underwent SBE, 124 386 (75.7%) patients underwent AG procedures. At baseline patients in both groups were similar, except for older age (68.5 for RG vs 71 for AG, p=0.043) and higher antiplatelet use (34.7% for RG vs 42.5% for AG, p=0.042) in AG group. Deeper scope insertion depth (depth level 3 for AG vs 1 for RG, p < 0.001) and lesser scope time (37.4 mins in AG vs 48.9 mins in RG, p<0.001) was observed with AG procedures. On multivariate analysis AG procedures were found to have 118 higher odds (95% CI 60.5-229.9, p <0.001) of having a deeper scope insertion than RG, and RG procedures had 11.9 higher odds (95% CI 6.7-17, p <0.001) of longer scope time compared to AG. No difference in the rates of adverse outcomes including, bleeding, perforation, aspiration and change in level of care were noted between the two modalities. (Table 1&2)2793_A Figure 1 No Caption available.Conclusion: AG approach is less time consuming and more likely to have a deeper extent of insertion compared to RG approach, with similar rates of complications. Unless the lesion of interest is in close proximity to the ileo-cecal valve, it may be more prudent to proceed with AG approach rather than RG approach.2793_B Figure 2 No Caption available.

Antegrade (AG) Versus Retrograde (RG) Stents for Ureteral Obstruction (UO) In Locally Advanced Cervical Cancer (CC) [3J

INTRODUCTION: UO is common in patients with newly diagnosed CC. Management of UO commonly occurs with stent or nephrostomy placement (NT). The success rates for AG and RG stents amongst this group have not been reported. We sought to document performance of these procedures to inform comparative effectiveness studies. METHODS: Medical records of patients with locally advanced CC and UO treated at our institution between 2000 - 2009 were reviewed. Failure of a procedure was defined as worsening hydronephrosis on imaging, rising creatinine, or need for an alternate method of management. RESULTS: 55 patients with stage IIIA-IVA CC were identified. Stages at presentation were 13% (IIIA), 60% (IIIB), and 27% (IVA). Fifty-one percent of patients presented with UO and 93% of these underwent a procedure. Fifty-four percent had attempted AG stent placement while 46% had attempt at RG stent. Thirty-eight percent of patients failed initial stent attempt: 50% failed via AG approach and 20% via RG. Amongst successful placement, mean number of follow up procedures secondary to stent failure was 3. Median stent survival was 120 days. Thirty percent of patients required long term management of UO with NT placement. Failure of UO management following NT placement was 0%. CONCLUSION: High short and long-term failure rates were seen with both AG and RG approaches and required multiple follow up procedures to manage UO. NT was most successful for long term management of UO. Given this, NT may be a reasonable initial management strategy for advanced stage CC with UO.

Role of Mitochondrial Retrograde Pathway in Regulating Ethanol-Inducible Filamentous Growth in Yeast.

In yeast, ethanol is produced as a by-product of fermentation through glycolysis. Ethanol also stimulates a developmental foraging response called filamentous growth and is thought to act as a quorum-sensing molecule. Ethanol-inducible filamentous growth was examined in a small collection of wine/European strains, which validated ethanol as an inducer of filamentous growth. Wine strains also showed variability in their filamentation responses, which illustrates the striking phenotypic differences that can occur among individuals. Ethanol-inducible filamentous growth in Σ1278b strains was independent of several of the major filamentation regulatory pathways [including fMAPK, RAS-cAMP, Snf1, Rpd3(L), and Rim101] but required the mitochondrial retrograde (RTG) pathway, an inter-organellar signaling pathway that controls the nuclear response to defects in mitochondrial function. The RTG pathway regulated ethanol-dependent filamentous growth by maintaining flux through the TCA cycle. The ethanol-dependent invasive growth response required the polarisome and transcriptional induction of the cell adhesion molecule Flo11p. Our results validate established stimuli that trigger filamentous growth and show how stimuli can trigger highly specific responses among individuals. Our results also connect an inter-organellar pathway to a quorum sensing response in fungi.

Clinical Correlation and MRI Finding in the Management of Fistula in Ano

Fistula is considered to be any abnormal passage which connects two epithelial surfaces. Parks fistula classification demonstrates the biggest practical significance and divides fistulae into inter-sphincteric, trans-sphincteric, supra-sphincteric, and extra-sphincteric. Diagnostic method options are retrograde (RTG) fistulography, computed tomography (CT) fistulography, and magnetic resonance imaging (MRI) of pelvic organs. The purpose of the study is to correlate clinical examination and operative findings with the findings of MRI and to draw efficacy of MRI as a preoperative diagnostic tool in the management of fistula in ano. This study was performed at the Surgery Department and MRI unit of the Radiology Department of JLNH and RC, Bhilai, from January 2014 to July 2015. Patients with perianal fistulae were included in our prospective study. All patients underwent high-spatial resolution MR imaging. MR imaging findings were correlated with the intraoperative surgical finding. MR imaging shows 7 fistulous patients with side branching and 16 with abscess cavity which was 100% intraoperatively correlated. Fifty-six patients out of 60 completely correlated with MRI for primary track which was clinically significant. MRI had 96% sensitivity and 100% specificity for primary tract and internal opening and 100% sensitivity and specificity for abscess and multiple tracks. MRI is useful in successful treatment of perianal fistulae by providing more accurate anatomical information about the amount of sphincter above the track and the position and level of the internal opening, thereby increasing the likelihood of successful surgical treatment. So, MRI is the very important preoperative investigation tool for fistula in ano.

Ejaculation and sperm characteristics in men with cauda equina and conus medullaris syndromes

Retrospective. The objective of the study was to describe the type of ejaculation in patients with cauda equina (CE) and conus medullaris (CM) lesions, and to analyse sperm quality. France. One hundred sixty-six patients with CE and CM lesions were included. Diagnosis was based on clinical (no motor responses, sensation or sacral reflexes) and urodynamic assessments (no detrusor activity). Vibromassage (VM) was used to induce ejaculation according to the recommendations for patients with spinal cord injury. If ejaculation did not occur, oral midodrine was administered in progressive doses. Retrograde ejaculation was systematically sought. Sperm parameters were analysed according to World Health Organisation recommendations (2010). Eighty-nine patients were included. Eleven ejaculated on the first VM trial (four anterograde (AE), six retrograde (RE) and one antero-retrograde (ARE)). Five patients continued trials of VM alone, two of whom ejaculated following a mean 1.9 trials (one RE, one ARE). Twenty-six patients underwent trials of VM+ midodrine, 18 of whom ejaculated following a mean 4.4 trials with a mean dose of 22.5 g of midodrine (2 AE, 13 RE and 5 ARE). Fifty-three ejaculates from 26 patients were analysed. Sperm concentration was low in 90.6% of samples; total necrospermia was found in 65% and asthenospermia in 95% of samples. Ejaculation is difficult to induce using VM in patients with CE and CM lesions, and requires high doses of midodrine. Sperm counts were generally low, and asthenospermia and necrospermia were found in the majority of specimens. Cryopreservation of sperm should be systematic in case of medically assisted procreation.