Free radicals have long been studied as a contributor to aging and disease processes. Endogenous production of radicals from cellular metabolism and exogenous sources from ultraviolet radiation and ...pollution can damage the skin on the cellular and tissue levels. Although the body possesses an elegant defense system to prevent radical damage, this innate system can be overwhelmed and lead to a state of oxidative stress or immunosuppression, and can even trigger carcinogenesis. Topical supplementation of antioxidants can provide additional protection to neutralize reactive oxygen species from both endogenous and exogenous sources. This review will discuss our current understanding of the mechanisms of free radical damage and evaluate the potential benefit of topical antioxidants in sunscreens and skin care products.
Background
Utility of robotic over laparoscopic approach has been an area of debate across all surgical specialties over the past decade. The fragility index (FI) is a metric that evaluates the ...frailty of randomized controlled trials (RCTs) findings by altering the status of patients from an event to non-event until significance is lost. This study aims to evaluate the robustness of RCTs comparing laparoscopic and robotic abdominopelvic surgeries through the FI.
Methods
A search was conducted in MEDLINE and EMBASE for RCTs with dichotomous outcomes comparing laparoscopic and robot-assisted surgery in general surgery, gynecology, and urology. The FI and reverse fragility Index (RFI) metrics were used to assess the strength of findings reported by RCTs, and bivariate correlation was conducted to analyze relationships between FI and trial characteristics.
Results
A total of 21 RCTs were included, with a median sample size of 89 participants (Interquartile range IQR 62–126). The median FI was 2 (IQR 0–15) and median RFI 5.5 (IQR 4–8.5). The median FI was 3 (IQR 1–15) for general surgery (
n
= 7), 2 (0.5–3.5) for gynecology (
n
= 4), and 0 (IQR 0–8.5) for urology RCTs (
n
= 4). Correlation was found between increasing FI and decreasing
p
-value, but not sample size, number of outcome events, journal impact factor, loss to follow-up, or risk of bias.
Conclusion
RCTs comparing laparoscopic and robotic abdominal surgery did not prove to be very robust. While possible advantages of robotic surgery may be emphasized, it remains novel and requires further concrete RCT data.
This paper studies the impact of supply chain power structure on firms' profitability in an assembly system with one assembler and two suppliers. Two power regimes are investigated—in a Single Power ...Regime, a more powerful firm acts as the Stackelberg leader to decide the wholesale price but not the quantity whereas in a Dual Power Regime, both the price and quantity decisions are granted to the more powerful firm. Tallying the power positions of the three firms, for each power regime we study three power structures and investigate the system's as well as the firms' preference of power. We find that when the assembler is the most powerful firm among the three, the system‐wide profit is the highest and so is the assembler's profit. The more interesting finding is that, if the assembler is not the most powerful player in the system, more power does not necessarily guarantee her a higher profit. Similarly, a supplier's profit can also decrease with the power he has. These results contrast with the conclusion for serial systems, where a firm always prefers more power. We also find that when both suppliers are more (less) powerful than the assembler, it can be beneficial (indifferent) for everyone if the two suppliers merge into a mega supplier to make decisions jointly. When the assembler is more powerful than one supplier and less so than the other, it is always better for the system to have the two suppliers merge, and for each individual firm, merging is preferred if the firm becomes the more powerful party after merging.
Buprenorphine-naloxone (bup/nal in 4:1 ratio; Suboxone; Reckitt Benckiser Pharmaceuticals Incorporation, Richmond, VA) is approved by the Food and Drug Administration for outpatient office-based ...addiction treatment. In the past few years, bup/nal has been increasingly prescribed off-label for chronic pain management. The current data suggest that bup/nal may provide pain relief in patients with chronic pain with opioid dependence or addiction. However, the unique pharmacological profile of bup/nal confers it to be a weak analgesic that is unlikely to provide adequate pain relief for patients without opioid dependence or addiction. Possible mechanisms of pain relief by bup/nal therapy in opioid-dependent patients with chronic pain may include reversal of opioid-induced hyperalgesia and improvement in opioid tolerance and addiction. Additional studies are needed to assess the implication of bup/nal therapy in clinical anesthesia and perioperative pain management.
Randomized controlled trials (RCTs) are regarded as high-level evidence, but the strength of their P values can be difficult to ascertain. The Fragility Index (FI) is a novel metric that evaluates ...the frailty of trial findings. It is defined as the minimum number of patients required to change from a non-event to event for the findings to lose statistical significance. This study aims to characterize the robustness of bariatric surgery RCTs by examining their FIs.
A search was conducted in MEDLINE, EMBASE, and CENTRAL from January 2000 to February 2022 for RCTs comparing two bariatric surgeries with statistically significant dichotomous outcomes. Bivariate correlation was conducted to identify associations between FI and trial characteristics.
A total of 35 RCTs were included with a median sample size of 80 patients (Interquartile range IQR 58-109). The median FI was 2 (IQR 0-5), indicating that altering the status of two patients in one treatment arm would overturn the statistical significance of results. Subgroup analyses of RCTs evaluating diabetes-related outcomes produced a FI of 4 (IQR 2-6.5), while RCTs comparing Roux-en-Y gastric bypass and sleeve gastrectomy had an FI of 2 (IQR 0.5-5). Increasing FI was found to be correlated with decreasing P value, increasing sample size, increasing number of events, and increasing journal impact factor.
Bariatric surgery RCTs are fragile, with only a few patients required to change from non-events to events to reverse the statistical significance of most trials. Future research should examine the use of FI in trial design.
Desmoplastic melanoma: A review Chen, Lucy L., BA; Jaimes, Natalia, MD; Barker, Christopher A., MD ...
Journal of the American Academy of Dermatology,
05/2013, Letnik:
68, Številka:
5
Journal Article
Recenzirano
Odprti dostop
Desmoplastic melanoma (DM) is a variant of spindle cell melanoma typically found on chronically sun-damaged skin of older individuals. Early diagnosis can be challenging because it is often ...amelanotic and has a predominantly dermal component. DM can be difficult to diagnose not only clinically but also histologically, and can be mistaken for a variety of benign and malignant nonmelanocytic spindle cell tumors when viewed on prepared histopathology slides. Pathologists have observed that DMs can manifest significant variation with respect to the extent of intratumoral cellularity, fibrosis, and/or perineural invasion. Furthermore, some tumors present with a pure desmoplastic invasive component (>90%) while other tumors display mixed features of DM and nondesmoplastic melanoma. This has led to the separation of DM into 2 histologic subtypes, pure and mixed. With a focus on the distinction between pure and mixed DM, this review will detail what is currently known about the diagnostic features of DM, discuss risk and prognostic factors, and examine the current literature on disease progression and management.
The current decolonizing global health movement is calling us to take a post-colonial perspective at the research and practice of global health, an area that has been re-defined by contemporary ...scholars and advocates with the purpose of promoting equity and justice. In this article, we summarize the main points of discussion from the Symposium organized by the editorial board of Global Health Research and Policy, convened in July 2021 in Wuhan, China. Experts participating in the symposium discussed what decolonizing global health means, how to decolonize it, and what criteria to apply in measuring its completion. Through the meeting, a consensus was reached that the current status quo of global health is still replete with various forms of colonial vestiges-ideologies and practices-, and to fully decolonize global health, systemic reforms must be taken that target the fundamental assumptions of global health: does investment in global health bring socioeconomic development, or is it the other way around? Three levels of colonial vestiges in global health were raised and one guiding principle was proposed when thinking of solutions for them. More theoretical discussion needs to be explored to guide practices to decolonize global health.
Numerous preclinical studies support the role of spinal neuroimmune activation in the pathogenesis of chronic pain, and targeting glia (eg, microglia/astrocyte)- or macrophage-mediated ...neuroinflammatory responses effectively prevents or reverses the establishment of persistent nocifensive behaviors in laboratory animals. However, thus far, the translation of those findings into novel treatments for clinical use has been hindered by the scarcity of data supporting the role of neuroinflammation in human pain. Here, we show that patients suffering from a common chronic pain disorder (lumbar radiculopathy), compared with healthy volunteers, exhibit elevated levels of the neuroinflammation marker 18 kDa translocator protein, in both the neuroforamina (containing dorsal root ganglion and nerve roots) and spinal cord. These elevations demonstrated a pattern of spatial specificity correlating with the patients' clinical presentation, as they were observed in the neuroforamen ipsilateral to the symptomatic leg (compared with both contralateral neuroforamen in the same patients as well as to healthy controls) and in the most caudal spinal cord segments, which are known to process sensory information from the lumbosacral nerve roots affected in these patients (compared with more superior segments). Furthermore, the neuroforaminal translocator protein signal was associated with responses to fluoroscopy-guided epidural steroid injections, supporting its role as an imaging marker of neuroinflammation, and highlighting the clinical significance of these observations. These results implicate immunoactivation at multiple levels of the nervous system as a potentially important and clinically relevant mechanism in human radicular pain, and suggest that therapies targeting immune cell activation may be beneficial for chronic pain patients.
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