Evaluation of a new packaging process for non-autoclavable endoscopes: results for the first 100 microbiological samples.

BACKGROUND: A new process for packaging endoscopes (SureStore®, Medical Innovations Group) immediately after they exit from washing and disinfection in an automated endoscope reprocessor (AER) allows for endoscopes to be stored for up to 15 days. AIM: To describe the microbiological quality of samples from gastrointestinal endoscopes following this process. METHODS: Three-month prospective study using microbiological sampling from a stock of 38 gastrointestinal endoscopes carried out in a French University Hospital. The compliance rate (proportion of samples ≤25 cfu with no pathogenic micro-organisms) and the rate of sterile samples (proportion of germ-free samples) were calculated. We then used multivariate analysis to determine the factors associated with the maintenance of sterility. FINDINGS: One hundred samples were taken from stored endoscopes: 31 stored for ≤3 days, 34 stored between 3 and 7 days, and 35 after storage between 7 and 15 days. The compliance rate was 98% and the sterile sample rate was 60%. Only the time between leaving the AER and packaging was significantly associated with the sterility of samples (P = 0.02). The probability of having a sterile sample decreased 17-fold when the endoscope was packaged >2 h after leaving the AER (P = 0.04) compared to an endoscope packaged within 1 h after leaving the AER. CONCLUSION: The SureStore process seems capable of satisfactorily maintaining compliance (98%) of samples taken from endoscopes stored for up to 15 days. The delay in packaging should not exceed 1 h, as the rate of sterile samples decreases thereafter.

Surgical Decisions in Primary Open Angle Glaucoma with Low or Normal Tension.

Glaucoma, given its insidious nature, is often coined 'the sneak thief of sight'. Following this trail of thought, primary open angle glaucoma with low or normal tension (POAGLNT) could be coined 'the king of thieves'. The lack of a compelling red fag of high intraocular pressure (IOP), together with the diurnal fuctuation of the deceptively low baseline IOP, POAGLNT poses a therapeutic challenge in terms of judging when to intervene, and how. In this review article, we will outline the considerations before undergoing surgery: risk stratification, defining goal in terms of target pressure and IOP modulation. We will also review the strengths, weaknesses and pearls of available options. How to cite this article: Shum JW, Leung DY. Surgical Decisions in Primary Open Angle Glaucoma with Low or Normal Tension. J Current Glau Prac 2013;7(3):121-127.

Multidetector CT and MRI of ostial atresia of the coronary sinus, associated collateral venous pathways and cardiac anomalies.

AIM: To analyse the multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI) findings in patients with atresia of the coronary sinus orifice (CSA). MATERIALS AND METHODS: MDCT findings of 15 consecutive adult patients with CSAs were retrospectively analysed. The patients underwent contrast-enhanced electrocardiography-gated MDCT (n = 13) or both CT and MRI (n = 2). RESULTS: The mean size of the coronary sinus (CS) was 14.2 mm (range 5.5-24 mm) and 11 patients (73.3%) showed CS dilatation (diameter ≥12 mm). The mean length of the atretic CS segment was 2.9 mm (range 0-8 mm). Different forms of venous collateral pathways were observed in the CSA patients. Nine (60%) of the 15 CSA patients had communication between the right atrium (RA; n = 6) or LA (n = 5) and CS via intraseptal veins; six patients (40%) had persistent left superior caval veins; communications were also observed between the CS and RA (n = 4) or LA (n = 4); two patients had collateral venous pathways between dilated cardiac veins with RA; two patients had unroofing of the CS as outlet channels. Nine patients (60%) had cardiac anomalies: coronary artery fistula to the pulmonary artery (n = 6) or left ventricular base and CS (n = 1), atrial septal defects (n = 2), and a ventricular septal defect (n = 1). CONCLUSION: CSA patients have venous collateral pathways and a high incidence of associated cardiovascular anomalies such as coronary artery fistulae and atrial septal defects.

Angiographic and histologic comparison of experimental aneurysms embolized with hydrogel filaments.

BACKGROUND AND PURPOSE: The embolization of aneurysms with hydrogel filaments allow postprocedural CT and MR imaging studies without artifacts. We compared the performance of 3 hydrogel filament formulations in rabbit experimental aneurysms by using angiography and histologic samples. MATERIALS AND METHODS: Embolization of 35 rabbit elastase or bifurcation aneurysms was performed with 3 different formulations of detachable hydrogel filaments, including 1) polyethylene glycol opacified with aromatic iodine (PEG-I; n = 12), 2) polyethylene glycol opacified with barium sulfate (PEG-B; n = 12), or 3) polypropylene glycol opacified with barium sulfate (PPG-B; n = 11). Follow-up angiography was performed before the rabbits were killed at 2 (n = 7), 6 (n = 9), 10 (n = 8), or 26 (n = 11) weeks. Angiographic occlusion was scored according to the Raymond scale, and interval changes were assessed. The harvested aneurysms were evaluated on histologic examination. From the sections, we determined the percentage of the sac excluded from the vasculature and occupied by embolic devices by using image analysis. We compared results using the analysis of variance/t test or chi(2) test. RESULTS: The mean number of devices used to treat aneurysms in the PPG-B group was significantly greater than that used for the other 2 groups, though aneurysm volumes were similar among groups. Compared with immediate posttreatment occlusion scores, mean angiographic occlusion at follow-up was increased for all 3 hydrogel filament groups. On histologic examination, thrombus organization, neointima formation, and inflammation were similar to that observed in rabbit experimental aneurysms with other embolic devices containing platinum coils. CONCLUSIONS: The embolization of experimental aneurysms with hydrogel filaments resulted in durable angiographic and histologic occlusion from 2 to 26 weeks. With improvements, hydrogel filaments free from metallic coils show promise for endovascular use.

[Results of 4 years of microbiological testing of bronchoscopes]. / Endoscopes bronchiques: bilan de quatre années de contrôles microbiologiques.

INTRODUCTION: In the context of reducing endoscopy-related infectious risk and new national guidelines on microbiological samples from bronchoscopy, the results of a surveillance program set up in a hospital center were analyzed. METHODS: Over 4 years, scheduled samples were taken from disinfected bronchoscopes. Bacteriology and mycology tests were used to search for microorganisms. The results were interpreted as falling within three levels: target, alert, and action. Factors that could explain the contamination were studied: age of the bronchoscope, number of uses per year, brand, and model. RESULTS: Out of 96 scheduled samples taken, the compliance rate for the period was 83% and increased (p=0.06) over the 4 years. We identified 15 Pseudomonas (six aeruginosa and nine other species), one Stenotrophomonas, one enterobacterium, and two filamentous fungi. None of the factors studied had a significant effect on sample contamination. CONCLUSION: The microbiological surveillance of bronchoscopes is an indispensable part of the quality assurance of bronchoscope maintenance. It can lead to maintenance of the bronchoscope when a noncompliant result is found.

Cartilage and bone neoformation in rabbit carotid bifurcation aneurysms after endovascular coil embolization.

Occurrence and histomorphology of cartilage and bone neoformations was retrospectively evaluated in rabbit experimental aneurysms after endovascular coil embolization. During product development, 115 carotid bifurcation aneurysms were treated with hydrogel-containing devices (HydroCoil or target, n=77; HydroSoft or target, n=28; prototype Hydrogel-only, n=10; MicroVentionTerumo, Aliso Viejo, CA). Additional 29 aneurysms were treated with standard (n=22) or with degradable polymer-covered (n=7) platinum coils. After 4 to 52 weeks, the retrieved aneurysms were methylmethacrylate embedded, and ground sections were surface-stained with Rapid Bone Stain and Giemsa solution. Cartilage and/or bone tissue was assessed by light microscopy; respective tissue areas in the aneurysms were determined by computerized histomorphometry. Cartilage neoformation was observed from 26 to 52 weeks. Single chondrocytes to hyaline or fibrous cartilage areas, occupying up to 29% of the aneurysm cavity, were found in 6 aneurysms, treated with HydroCoil (n=4), Hydrogel-only (n=1), and resorbable polymer (n=1) devices. Chondral ossification associated cartilage neoformation in 2 of these 4 HydroCoil-treated aneurysms. Membranous woven and lamellar bone ossicles were observed from 13 to 52 weeks in 7 aneurysms, treated with HydroCoil (n=3) and platinum coil (n=4) devices. Altogether, cartilage and/or bone neoformation was observed in 13 (9%) of 144 rabbit bifurcation aneurysms treated with various embolic devices. Incidence was low until 26 weeks, but increased at 52 weeks in both, HydroCoil and standard platinum coil treated aneurysms. As the neoformations were predominantly located in proximity to the aneurysm neck, they could be related to the long-term mechanobiology of cell differentiation during fibrovascular healing of blood flow-exposed embolized aneurysms.

[Single-use laryngoscope blade assessment]. / Evaluation des lames de laryngoscopes à usage unique.

OBJECTIVES: To assess the feasibility of switching disposable laryngoscope blades and to compare the disposable blades available on the market to reusable blades within the context of a new variant of Creutzfeldt-Jakob disease. STUDY DESIGN: Comparative prospective study. MATERIAL AND METHODS: Study conducted on patients intubated for surgical procedures in all operating theatres of a university hospital. The anaesthetic practitioner filled in an assessment form giving a score on nine criteria for each blade used. Data were recorded on Epi Info software. Satisfaction scores of each criterion were compared for both disposable blades and reusable blades. RESULTS: Six brands of blades were tested with 225 blades. Disposable blades were evaluated as inferior to the reusable blades in 62% of cases. Two blades were reported as more satisfactory: the 670166 Rusch-Pilling and Vital View blades. CONCLUSION: The disposable blades were not easily accepted by the anaesthetists particularly for difficult intubations, which is why reusable blades should not be totally removed from practice. Single-use blades proposed by different manufacturers are not identical. We chose 670166 Rusch-Pilling blades, the best adapted to our institution. The switch to disposable blades would require that blade manufacturers improve the quality of the blades.

Regulation of osteoclasts by calcitonin and amphiphilic calcitonin conjugates: role of cytosolic calcium.

The peptide hormone calcitonin is a potent inhibitor of osteoclastic resorption, but it is unstable and poorly absorbed following oral administration. Conjugates of salmon calcitonin covalently linked to low-molecular-weight amphiphilic polymers show improved stability and absorption. The purpose of this study was to investigate the biological activity of these conjugates in vitro using rat osteoclasts and HEK-293 cells transfected with the C1a isoform of the calcitonin receptor. Salmon calcitonin or its conjugates (10 pM-10 nM) caused rapid arrest of osteoclast membrane ruffling and subsequent retraction. The same amphiphilic polymer attached to an unrelated protein had no effect on osteoclast morphology or motility. Since calcitonin-induced retraction of osteoclasts is thought to be mediated by Ca2+ signaling, we investigated the effects of calcitonin and its conjugates on cytosolic free Ca2+ concentration ([Ca24]i). In HEK-293 cells transfected with the calcitonin receptor, these agents induced transient elevations of [Ca2+]i. However, the rise of [Ca2+]i in HEK-293 cells occurred at concentrations 100-1000-fold higher than those required to elicit osteoclast retraction. To investigate the role of Ca2+ in osteoclast retraction, we preloaded cells with BAPTA to buffer changes in [Ca2+]i. BAPTA decreased the initial rate of calcitonin-induced osteoclast retraction, but it did not affect the degree of retraction 2-3 hours following calcitonin, indicating that retraction is mediated primarily by Ca(2+)-independent processes. We conclude that calcitonin conjugates cause osteoclast retraction and [Ca2+]i signaling in a manner similar to that elicited by calcitonin. Thus, orally bioavailable calcitonin conjugates show potential for use as antiresorptive agents.

The human chemoattractant complement C5a receptor inhibits cyclic AMP accumulation through Gi and Gz proteins.

The human C5a receptor is known to signal through Gi proteins. The ability of the cloned C5a receptor to inhibit adenylyl cyclase or to stimulate phospholipase C through Gi proteins was examined in transfected cells. Activation of recombinant C5a receptors resulted in the stimulation of phospholipase C in Ltk- cells and inhibition of adenylyl cyclase in 293 cells. Pertussis toxin potently abolished both responses indicating the involvement of Gi proteins. Previous studies have shown that Gi-mediated inhibition of adenylyl cyclase can be similarly regulated by the pertussis toxin-insensitive GZ. In 293 cells co-transfected with the alpha subunit of GZ, the C5a-mediated inhibition of cAMP accumulation became pertussis toxin-resistant, signifying functional coupling between the C5a receptor and GZ. However, GZ cannot substitute for Gi in the C5a-induced stimulation of phospholipase C or inhibition of adenylyl cyclase in Ltk- cells.

The N-terminal 96 residues of MCM1, a regulator of cell type-specific genes in Saccharomyces cerevisiae, are sufficient for DNA binding, transcription activation, and interaction with alpha 1.

MCM1 performs several functions necessary for its role in regulating cell type-specific gene expression in the yeast Saccharomyces cerevisiae: DNA binding, transcription activation, and interaction with coregulatory proteins such as alpha 1. We analyzed a set of MCM1 deletion derivatives using in vivo reporter gene assays and in vitro DNA-binding studies to determine which regions of MCM1 are important for its various activities. We also analyzed a set of LexA-MCM1 hybrids to examine the ability of different segments of MCM1 to activate transcription independent of MCM1's DNA-binding function. The first third of MCM1 [MCM1(1-96)], which includes an 80-residue segment homologous to the mammalian serum response factor, was sufficient for high-affinity DNA binding, for activation of reporter gene expression, and for interaction with alpha 1 in vitro and in vivo. However, the ability of MCM1(1-96) to activate transcription and to interact with alpha 1 was somewhat reduced compared with wild-type MCM1 [MCM1(1-286)]. Optimal interaction with alpha 1 required residues 99 to 117, in which 18 of 19 amino acids are acidic in character. Optimal transcription activation required a segment from residues 188 to 286, in which 50% of the amino acids are glutamine. Deletion of this segment from MCM1 reduced expression of reporter genes by about twofold. Moreover, LexA-MCM1 hybrids containing this segment were able to activate expression of reporter genes that rely on LexA binding sites as potential upstream activation sequences. Thus, glutamine-rich regions may contribute to the activation function of yeast transcription activators, as has been suggested for glutamine-rich mammalian proteins such as Sp1.

Relative contributions of MCM1 and STE12 to transcriptional activation of a- and alpha-specific genes from Saccharomyces cerevisiae.

We have examined the relative contributions of MCM1 and STE12 to the transcription of the a-specific STE2 gene by using a 367 bp fragment from the STE2 5'-noncoding region to drive expression of a reporter lacZ gene. Mutation of the MCM1 binding site destroyed MCM1.alpha 2-mediated repression in alpha cells and dramatically reduced expression in a cells. The residual expression was highly stimulated by exposure of cells to pheromone. Likewise, the loss of STE12 function reduced lacZ expression driven by the wild-type STE2 fragment. In the absence of both MCM1 and STE12 functions, no residual expression was observed. Thus, the STE2 fragment appears to contain two distinct upstream activation sequences (UASs), one that is responsible for the majority of expression in cells not stimulated by pheromone, and one that is responsible for increased expression upon pheromone stimulation. In further support of this idea, a chemically synthesized version of the STE2 MCM1 binding site had UAS activity, but the activity was neither stimulated by pheromone nor reduced in ste12 mutants. Although transcription of alpha-specific genes also requires both MCM1 and STE12, these genes differ from a-specific genes in that they have a single, MCM1-dependent UAS system. The activity of the minimal 26 bp UAS from the alpha-specific STE3 gene was both stimulated by pheromone and reduced in ste12 mutants. These data suggest that at alpha-specific genes STE12 and MCM1 exert their effects through a single UAS.

Central nervous system involvement in non-Hodgkin's lymphoma.

Fifty-eight Hong Kong Chinese patients with CNS lymphoma were reviewed (primary seven, secondary 51). The incidence of secondary CNS lymphoma in patients with non-Hodgkin's lymphoma was estimated to be 9.4%. The Working Formulation separated subtypes which had a special propensity to involve the CNS. Significant proportions of our patients with secondary CNS lymphoma had other features which were known to be associated with a high risk of CNS disease including stage IV (48/51, 91.4%), bone marrow (26/51, 50.9%), peripheral blood (7.51, 13.7%), nasal (7/51, 13.7%), orbital (3/51, 5.9%), testicular (2/51, 3.9%) and bulky retroperitoneal (6/51, 11.8%) disease. 82% of patients with secondary CNS lymphoma had concurrent systemic disease and a further 12% had systemic relapse shortly afterward. CNS lymphoma is associated with poor prognosis and only 29% and 14% of the patients with primary and secondary CNS lymphoma respectively survived beyond 1 year. Patients responding to therapy had significantly better survival. 69.9% of the deaths were related to progressive systemic disease.

Operative cholangiography: evaluation of its routine use in 569 cholecystectomies.

From 1974 till 1979, 569 cholecystectomies with routine operative cholangiography were performed in the university surgical unit, Kwong Wah Hospital, Hong Kong, for non-malignant disease of the gallbladder. Gallstones were present in 522 cases. Acalculous cholecystitis occurred in 47 cases. At least one of the clinical or operative indications to explore the common bile duct was present in 312 of the patients. However, in this group of patients in whom routine operative cholangiography was done, exploration of the common bile duct was performed in only 147, thus avoiding unnecessary exploration of the duct in 165 cases (52.8%). In the remaining 257 patients in whom there was no indication to explore the common bile duct, operative cholangiography revealed unexpected stones in the common bile duct in 14 (5.5%). After choledochotomy, post exploratory operative T-tube cholangiography was performed to rule out overlooked stones, which were present in six cases (6/161, i.e., 3.7%). Postoperative T-tube cholangiography performed on the 12th to the 14th postoperative day showed retained stones in 17 cases, giving an incidence of known retained stones of 11% (17/161) of cholecystectomies with exploration of the common bile ducts, or 3% (17/569) in the whole series of cholecystectomies.