The switch from an outcrossing mode of mating enforced by self-incompatibility to self-fertility in the Arabidopsis thaliana lineage was associated with mutations that inactivated one or both of the two genes that comprise the self-incompatibility (SI) specificity-determining S-locus haplotype, the S-locus receptor kinase (SRK) and the S-locus cysteine-rich (SCR) genes, as well as unlinked modifier loci required for SI. All analyzed A. thaliana S-locus haplotypes belong to the SA, SB, or SC haplotypic groups. Of these three, the SC haplotype is the least well characterized. Its SRKC gene can encode a complete open-reading frame, although no functional data are available, while its SCRC sequences have not been isolated. As a result, it is not known what mutations were associated with inactivation of this haplotype. Here, we report on our analysis of the Lz-0 accession and the characterization of its highly rearranged SC haplotype. We describe the isolation of its SCRC gene as well as the subsequent isolation of SCRC sequences from other SC-containing accessions and from the A. lyrata S36 haplotype, which is the functional equivalent of the A. thaliana SC haplotype. By performing transformation experiments using chimeric SRK and SCR genes constructed with SC-and S36-derived sequences, we show that the SRKC and SCRC genes of Lz-0 and at least a few other SC-containing accessions are nonfunctional, despite SCRC encoding a functional full-length protein. We identify the probable mutations that caused the inactivation of these genes and discuss our results in the context of mechanisms of S-locus inactivation in A. thaliana.T HE switch from an outcrossing mode of mating to selffertility was a major transition in the evolutionary history of Arabidopsis thaliana. Recent studies have shown that this switch was accompanied by multiple independent losses of self-incompatibility (SI), the major mechanism that promotes outcrossing in the Brassicaceae Shimizu et al. 2008; Boggs et al. 2009a). In this family, SI is controlled by numerous haplotypes of the S locus. Within each S-locus haplotype (hereafter S haplotype), are two genes that determine specificity in the SI response: one gene encodes the stigma-expressed S-locus receptor kinase (SRK) and the other encodes the pollen coat-localized ligand for SRK, the S-locus cysteine-rich (SCR) protein. The SRK and SCR proteins are highly polymorphic and co-evolving proteins (Sato et al. 2002) and their haplotype-specific interaction is responsible for the specific recognition and inhibition by the stigma epidermis of self-related pollen (i.e., pollen derived from the same flower, other flowers on the same plant, or plants expressing the same S haplotype) (reviewed in Rea and Nasrallah 2008). Consequently, an understanding of the genetic events associated with the switch to self-fertility in the A. thaliana lineage was sought through analysis of SRK and SCR sequences harbored by various A. thaliana geographical accessions (Kusaba et al. 2001;Shimizu et al. 2004Shimizu et al....
Cryptococcal meningitis is an uncommon and severe infection that tends to affect immunocompromised hosts worldwide and in the United States. Annually it is estimated that there are 200 000 cases of cryptococcal meningitis, with the most recent estimate of 3400 cases per year in the United States alone. However, despite the low incidence, 1-year mortality is estimated at 20% to 30% even with long-term consolidation antifungal therapy. A 37-year-old man presented to the emergency department with headaches, dysarthria, hallucinations, and acute worsening of altered mental status, and he was found to have increased intracranial pressure, cerebrospinal fluid leukocytosis, and few encapsulated yeasts consistent with Cryptococcus neoformans meningitis in addition to radiologic evidence consistent with a cryptococcoma of the lungs. This report highlights the occurrence of Cryptococcus neoformans meningitis in a presumed immunocompetent host. The clinician should be aware of sources of minor immunosuppression, as they may contribute to development of Cryptococcus neoformans meningitis. Mortality in this condition remains high due to subacute presentations and delayed diagnosis in non-immunocompromised patients.
Purpose -In today's globally competitive environment, customers only want to pay for value-added activity. They are not willing to pay for inefficiencies, such as those incurred through extra motion, or time spent searching for data, information, or tools. Although these wastes may be transparent to customers, they usually manifest themselves in the company's market share and bottom line. The purpose of this paper is to describe how the visual workplace helps increase efficiency by eliminating non-value added activities. The visual workplace improves performance by providing information, enabling workers through self-direction and empowerment to quickly make decisions without requiring oversight. While its practice in the office environment is increasing, it is still not as consistently practiced as it is in the manufacturing environment. Design/methodology/approach -Utilizing benchmarking, a case study approach and analysis was conducted. Findings -Visual workplace practices are very common in manufacturing environments. While the practices and usefulness are just as useful in business process environments, there is found to be a reluctance to fully embrace the practices. Practical implications -The application of visual work practices requires business leaders to create, utilize, and support visual communication tools to manage their business. Its usage can be effectively applied to business processes to eliminate inefficiencies and decrease lost time. Originality/value -The usefulness of visual workplace practices, once embraced by business leaders, will increase business performance by increasing efficiency and reducing waste.
Background and Aims Walled-off pancreatic necrosis is a well-known serious adverse event of severe acute pancreatitis. EUS-guided transluminal access followed by direct endoscopic necrosectomy is increasingly used to remove necrosis, with good efficacy and a superior safety profile when compared with surgery. However, a percentage of patients is too critically ill to undergo this procedure or lack an appropriate transluminal window for access. Here we describe the use of percutaneous flexible endoscopic necrosectomy (PEN) with use of standard-sized upper endoscopes and accessories in a retrospective single-institution experience with a video demonstration of 1 patient in the series. Methods The authors present a 23-patient retrospective case series of PEN with standard-sized endoscopes. The series includes 12 patients from a previously published analysis in 2016 and 11 additional patients from 2013 to 2018. A representative case illustrates the described technique in a patient with severe acute pancreatitis complicated by multisystem organ failure who required immediate drainage of a pancreatic fluid collection and placement of a percutaneous drain into the collection for decompression. The drain was serially upsized to 28F, and its tract was used for PEN. Results A total of 23 patients have undergone PEN at our institution. On average, the size of the pancreatic fluid collection was 11.6 cm in cross-sectional diameter. Of those 23 patients, 11 presented with symptoms of severe disease. The median time from onset of symptoms to PEN was 84 days. The median number of procedures per patient was 2.1. The median time to complete resolution of symptoms and fluid collections was 67 days. In total, resolution was reached in 22 of 23 patients. Two patients died of unrelated causes. Conclusion PEN is a minimally invasive and effective treatment approach to walled-off pancreatic necrosis in patients who are not amenable to transluminal drainage and in whom percutaneous drains have been successfully placed. This case series demonstrates the efficacy and safety of this approach. A randomized prospective trial would be warranted to validate these results.
Acute, high-grade esophageal perforation and postoperative leak after esophagogastrostomy are associated with high morbidity and mortality due to the development of mediastinitis and thoracic contamination. Endoscopic vacuum therapy has proven to be a feasible, safe therapy for management of esophageal wall defects, but with limited success. We describe a retrospective single-center analysis of two patients who underwent endoscopic vacuum therapy for significant esophageal disruptions with a median cross-sectional diameter of 10.7 cm. The technique involved the use of a standard upper video endoscope, nasogastric tube, and vacuum-assisted closure dressing kit, with endoscopic placement of a polyurethane sponge and nasogastric tube assembly into the mediastinal or thoracic cavity. Serial washout and debridement were performed prior to each sponge insertion. Data were collected on indication, size of the cavities, time to intervention, number of procedures, time to resolution, outcomes, and adverse events. Two patients underwent therapy with a mean age of 69.5. The median size of the collections via longest cross-sectional diameter was 10.7 cm. The average number of endoscopic vacuum therapy performed was six and average duration of therapy was 49 days. Complete resolution was achieved in both patients. One patient died 6 weeks later due to severe sepsis from aspiration pneumonia. Endoscopic washout and debridement followed by endoscopic vacuum therapy can be effective for large, even multiple, thoracic and mediastinal contaminations following esophageal perforation and gastroesopagheal anastomotic dehiscence and leaks in appropriately selected patients.
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