Background
Previous studies comparing early laparoscopic cholecystectomy (ELC) with delayed laparoscopic cholecystectomy (DLC) for acute cholecystitis were incomplete. A meta‐analysis was undertaken ...to compare the cost‐effectiveness, quality of life, safety and effectiveness of ELC versus DLC.
Methods
PubMed, Embase, the Cochrane Library and Web of Science were searched for randomized clinical trials (RCTs) that compared ELC (performed within 7 days of symptom onset) with DLC (undertaken at least 1 week after symptoms had subsided) for acute cholecystitis.
Results
Sixteen studies reporting on 15 RCTs comprising 1625 patients were included. Compared with DLC, ELC was associated with lower hospital costs, fewer work days lost (mean difference (MD) –11·07 (95 per cent c.i. –16·21 to −5·94) days; P < 0·001), higher patient satisfaction and quality of life, lower risk of wound infection (relative risk 0·65, 95 per cent c.i. 0·47 to 0·91; P = 0·01) and shorter hospital stay (MD −3·38 (−4·23 to −2·52) days; P < 0·001), but a longer duration of operation (MD 11·12 (4·57 to 17·67) min; P < 0·001). There were no significant differences between the two groups in mortality, bile duct injury, bile leakage, conversion to open cholecystectomy or overall complications.
Conclusion
For patients with acute cholecystitis, ELC appears as safe and effective as DLC. ELC might be associated with lower hospital costs, fewer work days lost, and greater patient satisfaction.
The sooner the better
A repeated challenge in launching a two-sided market platform is how to ignite the cross-side network effects to jump-start adoption. This research note studies “piggybacking”—expanding the focal ...market to recruit exclusive users from external networks—as a new and nonpricing control to launch platforms in conjunction with pricing controls. We first consider consumer-side piggybacking. Our results provide a rich set of novel insights into strategies that platforms use to monetize exclusive access to external users with nontrivial characterizations of the interplay among piggybacking, cross-side network effects, and price competition. We identify conditions when piggybacking is profit improving and when it leads to a prisoner’s dilemma, depending on the piggybacking cost and strengths of cross-side network effects. Among others, we show that piggybacking may intensify rather than ease price competition. We then consider provider-side piggybacking, and we show that the insights are qualitatively the same as consumer-side piggybacking except that the prisoner’s dilemma disappears if piggybacking providers multihome.
A repeated challenge in launching a two-sided market platform is how to ignite the cross-side network effects to jump-start adoption. Prior literature often addresses this issue by using pricing controls—a high price on one side to raise the margin and a low price on the other to attract users—or the “seesaw principle.” More recently, platforms are increasingly embracing nonpricing controls to accelerate user adoptions. Little is known, however, about the role of nonpricing controls and their interplay with pricing controls. In this research note, using a game-theoretic framework, we study “piggybacking”—that is, expanding the focal market to recruit exclusive users from external networks—as a new and nonpricing control to launch platforms in conjunction with pricing controls. We first consider consumer-side piggybacking. In a standard “competitive bottlenecks” setting in which consumers single home and providers multihome, we provide a rich set of novel insights into strategies that platforms use to monetize exclusive access to external users with nontrivial characterizations of the interplay among piggybacking, cross-side network effects, and price competition. We identify necessary and sufficient conditions when piggybacking is profit improving and when it leads to a prisoner’s dilemma, depending on the piggybacking cost and strengths of cross-side network effects. Among others, we show that, if the platforms’ equilibrium strategies were to subsidize consumers (when provider-side network effects are stronger than consumer-side network effects), piggybacking may intensify rather than ease price competition. In contrast, if the platforms’ equilibrium strategies were to subsidize providers (when provider-side network effects are weaker than consumer-side network effects), piggybacking may ease price competition. Interestingly, piggybacking reinforces the seesaw principle for the piggybacking platform. We provide a full characterization on such nontrivial equilibrium outcomes. We then consider provider-side piggybacking, and we show that the insights are qualitatively the same as consumer-side piggybacking except that the prisoner’s dilemma disappears if piggybacking providers multihome. Managerial implications for platform practitioners are also discussed.
As a generic property, all substances transfer heat through microscopic collisions of constituent particles
. A solid conducts heat through both transverse and longitudinal acoustic phonons, but a ...liquid employs only longitudinal vibrations
. As a result, a solid is usually thermally more conductive than a liquid. In canonical viewpoints, such a difference also serves as the dynamic signature distinguishing a solid from a liquid. Here, we report liquid-like thermal conduction observed in the crystalline AgCrSe
. The transverse acoustic phonons are completely suppressed by the ultrafast dynamic disorder while the longitudinal acoustic phonons are strongly scattered but survive, and are thus responsible for the intrinsically ultralow thermal conductivity. This scenario is applicable to a wide variety of layered compounds with heavy intercalants in the van der Waals gaps, manifesting a broad implication on suppressing thermal conduction. These microscopic insights might reshape the fundamental understanding on thermal transport properties of matter and open up a general opportunity to optimize performances of thermoelectrics.
Gut microbiota and IBD: causation or correlation? Ni, Josephine; Wu, Gary D; Albenberg, Lindsey ...
Nature reviews. Gastroenterology & hepatology,
10/2017, Letnik:
14, Številka:
10
Journal Article
Recenzirano
Odprti dostop
A general consensus exists that IBD is associated with compositional and metabolic changes in the intestinal microbiota (dysbiosis). However, a direct causal relationship between dysbiosis and IBD ...has not been definitively established in humans. Findings from animal models have revealed diverse and context-specific roles of the gut microbiota in health and disease, ranging from protective to pro-inflammatory actions. Moreover, evidence from these experimental models suggest that although gut bacteria often drive immune activation, chronic inflammation in turn shapes the gut microbiota and contributes to dysbiosis. The purpose of this Review is to summarize current associations between IBD and dysbiosis, describe the role of the gut microbiota in the context of specific animal models of colitis, and discuss the potential role of microbiota-focused interventions in the treatment of human IBD. Ultimately, more studies will be needed to define host-microbial relationships relevant to human disease and amenable to therapeutic interventions.
Motivation: Next-generation sequencing captures sequence differences in reads relative to a reference genome or transcriptome, including splicing events and complex variants involving multiple ...mismatches and long indels. We present computational methods for fast detection of complex variants and splicing in short reads, based on a successively constrained search process of merging and filtering position lists from a genomic index. Our methods are implemented in GSNAP (Genomic Short-read Nucleotide Alignment Program), which can align both single- and paired-end reads as short as 14 nt and of arbitrarily long length. It can detect short- and long-distance splicing, including interchromosomal splicing, in individual reads, using probabilistic models or a database of known splice sites. Our program also permits SNP-tolerant alignment to a reference space of all possible combinations of major and minor alleles, and can align reads from bisulfite-treated DNA for the study of methylation state. Results: In comparison testing, GSNAP has speeds comparable to existing programs, especially in reads of ≥70 nt and is fastest in detecting complex variants with four or more mismatches or insertions of 1–9 nt and deletions of 1–30 nt. Although SNP tolerance does not increase alignment yield substantially, it affects alignment results in 7–8% of transcriptional reads, typically by revealing alternate genomic mappings for a read. Simulations of bisulfite-converted DNA show a decrease in identifying genomic positions uniquely in 6% of 36 nt reads and 3% of 70 nt reads. Availability: Source code in C and utility programs in Perl are freely available for download as part of the GMAP package at http://share.gene.com/gmap. Contact: twu@gene.com
Background and purpose
Restless legs syndrome (RLS) is an underestimated movement disorder in patients with end‐stage renal disease (ESRD). Several clinical and laboratory factors were inconsistently ...reported to associate with RLS. We aim to perform a large‐scale multicenter study to investigate the possible associated risk factors of RLS in patients with ESRD in Taiwan, a country with the highest incidence of uremia in the world.
Methods
From October 2009 to October 2011, we constitutively recruited 1130 patients with ESRD from 17 hemodialysis centers. Demographic, laboratory data, presence and severity of RLS were collected. Odds ratios (ORs) were estimated by logistic regression models.
Results
We found the prevalence of RLS to be 25.3% in patients with ESRD. Having type 2 diabetes OR = 3.61 (2.27–5.77), P < 0.01, low serum transferrin saturation OR = 1.42 (1.01–2.03), P < 0.05 and duration of dialysis OR = 1.09 (1.03–1.14), P < 0.01 were associated with RLS. In contrast, high serum hemoglobin level was inversely associated with RLS OR = 0.61 (0.40–0.89), P < 0.05. RLS has a significant impact on sleep quality in dialysis patients. Among patients with RLS, history of type 2 diabetes OR = 4.04 (1.65–10.79), P < 0.05, low serum hemoglobin level OR = 5.41 (2.43–13.12), P < 0.01 and duration of dialysis OR = 1.01 (1.01–1.02), P < 0.01 were associated with increased severity of RLS.
Conclusions
Our findings demonstrated that RLS is common in Taiwanese dialysis patients. Clinicians should have a high suspicion for the presence of RLS symptoms in patients with ESRD, especially those with type 2 diabetes, anemia, low serum iron status and long duration of dialysis.
The Color of Successtells of the astonishing transformation of Asians in the United States from the "yellow peril" to "model minorities"--peoples distinct from the white majority but lauded as ...well-assimilated, upwardly mobile, and exemplars of traditional family values--in the middle decades of the twentieth century. As Ellen Wu shows, liberals argued for the acceptance of these immigrant communities into the national fold, charging that the failure of America to live in accordance with its democratic ideals endangered the country's aspirations to world leadership.
Weaving together myriad perspectives, Wu provides an unprecedented view of racial reform and the contradictions of national belonging in the civil rights era. She highlights the contests for power and authority within Japanese and Chinese America alongside the designs of those external to these populations, including government officials, social scientists, journalists, and others. And she demonstrates that the invention of the model minority took place in multiple arenas, such as battles over zoot suiters leaving wartime internment camps, the juvenile delinquency panic of the 1950s, Hawaii statehood, and the African American freedom movement. Together, these illuminate the impact of foreign relations on the domestic racial order and how the nation accepted Asians as legitimate citizens while continuing to perceive them as indelible outsiders.
By charting the emergence of the model minority stereotype,The Color of Successreveals that this far-reaching, politically charged process continues to have profound implications for how Americans understand race, opportunity, and nationhood.
Although the use of sorafenib appears to increase the survival rate of renal cell carcinoma (RCC) patients, there is also a proportion of patients who exhibit a poor primary response to sorafenib ...therapy. It is therefore critical to elucidate the mechanisms underlying sorafenib resistance and find representative biomarkers for sorafenib treatment in RCC patients. Herein, we identified a long non-coding RNA referred to as lncRNA-SRLR (sorafenib resistance-associated lncRNA in RCC) that is upregulated in intrinsically sorafenib-resistant RCCs. lncRNA-SRLR knockdown sensitized nonresponsive RCC cells to sorafenib treatment, whereas the overexpression of lncRNA-SRLR conferred sorafenib resistance to responsive RCC cells. Mechanistically, lncRNA-SRLR directly binds to NF-κB and promotes IL-6 transcription, leading to the activation of STAT3 and the development of sorafenib tolerance. A STAT3 inhibitor and IL-6-receptor antagonist both restored the response to sorafenib treatment. Moreover, a clinical investigation demonstrated that high levels of lncRNA-SRLR correlated with poor responses to sorafenib therapy in RCC patients. Collectively, lncRNA-SRLR may serve as not only a predictive biomarker for inherent sorafenib resistance but also as a therapeutic target to enhance responses to sorafenib in RCC patients.
The mutual relationship between the intestinal microbiota and its mammalian host is influenced by diet. Consumption of various nutrients affects the structure of the microbial community and provides ...substrates for microbial metabolism. The microbiota can produce small molecules that are absorbed by the host and affect many important physiological processes. Age-dependent and societal differences in the intestinal microbiota could result from differences in diet. Examples include differences in the intestinal microbiota of breastfed vs formula-fed infants or differences in microbial richness in people who consume an agrarian plant-based vs a Western diet, which is high in meat and fat. We review how diet affects the structure and metabolome of the human intestinal microbiome and may contribute to health or the pathogenesis of disorders such as coronary vascular disease and inflammatory bowel disease.
It has been argued that platform technology owners cocreate business value with other firms in their platform ecosystems by encouraging complementary invention and exploiting indirect network ...effects. In this study, we examine whether participation in an ecosystem partnership improves the business performance of small independent software vendors (ISVs) in the enterprise software industry and how appropriability mechanisms influence the benefits of partnership. By analyzing the partnering activities and performance indicators of a sample of 1,210 small ISVs over the period 1996-2004, we find that joining a major platform owner ' s platform ecosystem is associated with an increase in sales and a greater likelihood of issuing an initial public offering (IPO). In addition, we show that these impacts are greater when ISVs have greater intellectual property rights or stronger downstream capabilities. This research highlights the value of interoperability between software products, and stresses that value cocreation and appropriation are not mutually exclusive strategies in interfirm collaboration.