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The biological effects of camphorquinone (CQ), an initiator for light-polymerized resins, have been reported to relate to its ability to generate free radicals and cause radical-induced membrane damage via lipid peroxidation. However, the effects of CQ on lipids other than peroxidation may result in unfavorable tissue responses especially at concentrations that are not overtly toxic to cells. The purpose of the current study was to examine the effects of CQ on cell lipid metabolism at subtoxic concentrations, with or without visible light irradiation. HCP and THP-1 cells were exposed to CQ with or without light irradiation under clinically relevant conditions and lipid metabolism was analyzed using 14C-labeling and thin-layer chromatography. We found that CQ increased synthesis of neutral lipids, such as triglycerides, from 7 to nearly 15% of the total and diglycerides from 2% to about 3% of the total in HCP cells, while synthesis of phospholipids, such as sphingomyelin, was decreased by 1-1.5%. In THP-1 cells cholesterol synthesis increased more than 2-fold and cholesterol ester synthesis increased more than 5-fold. Light-activated CQ did not differ significantly in terms of its bioactivity compared to no-light conditions. We conclude that CQ significantly altered the metabolism of several important structural lipids in two cell types at sub-toxic concentrations that are clinically relevant. These changes in lipid metabolism may in turn affect membrane integrity and permeability and possibly lead to significant changes in cell responses.  相似文献   
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Accumulating evidence suggests that presence of macrophages in the tumor microenvironment add to the invasive and tumor-promoting hallmarks of cancer cells by secreting angiogenic and growth factors. RKIP is a known metastasis suppressor and interferes with several steps of metastasis. However, the mechanistic underpinnings of its function as a broad metastasis suppressor remain poorly understood. Here, we establish a novel pathway for RKIP regulation of metastasis inhibition through the negative regulation of RANTES/CCL5 thereby limiting tumor macrophage infiltration and inhibition of angiogenesis. Using a combination of loss- and gain-of-function approaches, we show that RKIP hinders breast cancer cell invasion by inhibiting expression of the CC chemokine CCL5 in vitro. We also show that the expression levels of RKIP and CCL5 are inversely correlated among clinical human breast cancer samples. Using a mouse allograft breast cancer transplantation model, we highlight that ectopic expression of RKIP significantly decreases tumor vasculature, macrophage infiltration and lung metastases. Mechanistically, we demonstrate that the inhibition of the CCL5 expression is the cause of the observed effects resulting from RKIP expression. Taken together, our results underscore the significance of RKIP as important negative regulator of tumor microenvironment.  相似文献   
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BackgroundMechanical low back pain (MLBP) is a commonly encountered entity in clinical practice. Pain relief and restoration of functional capacity are management goals.Aims and objectivesTo compare the efficacy and tolerability of flupirtine, a selective neuronal potassium channel-opener (SNEPCO), with tramadol, a widely-used opioid analgesic, in MLBP.MethodsThis randomized, single-blinded, intention to treat (ITT) trial started with 240 non-steroidal anti-inflammatory drug (NSAID) intolerant patients who were prescribed either tablet flupirtine (100 mg twice daily) or capsule tramadol (50 mg twice daily), for 4 weeks. Follow-up was done on days 14, 28 and 4 weeks after treatment completion. Assessment of improvements in Indian Health Assessment Questionnaire Disability Index (Indian HAQ-DI), Visual Analogue Scale (VAS), Numerical Rating Scale (NRS) and measurement of Pain Relief Rate (PRR) were performed. Adverse events were recorded.ResultsOne hundred and seven patients receiving flupirtine and 103 receiving tramadol were analyzed on an ITT basis. Scores in Indian HAQ-DI, VAS and NRS improved significantly in both groups in the last visit, but more so with flupirtine. PRR was reasonably higher with flupirtine, [59 (55.14%)] patients experiencing significant to complete pain relief at the end of the study, compared to tramadol [41 (39.81%)]. Adverse effects were less with flupirtine [26 (24.30%) versus 41 (39.81%), p < 0.05], minimizing drop-outs.ConclusionFlupirtine has better sustained efficacy and tolerability than tramadol in MLBP.  相似文献   
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Digestive Diseases and Sciences - Colectomy risk after acute severe ulcerative colitis (ASUC) has not been compared between Eastern and Western countries. We compared the 1-year colectomy risk...  相似文献   
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BackgroundThe impact of race and socioeconomic status on clinical outcomes has not been quantified in patients hospitalized with coronavirus disease 2019 (COVID-19).ObjectiveTo evaluate the association between patient sociodemographics and neighborhood disadvantage with frequencies of death, invasive mechanical ventilation (IMV), and intensive care unit (ICU) admission in patients hospitalized with COVID-19.DesignRetrospective cohort study.SettingFour hospitals in an integrated health system serving southeast Michigan.ParticipantsAdult patients admitted to the hospital with a COVID-19 diagnosis confirmed by polymerase chain reaction.Main MeasuresPatient sociodemographics, comorbidities, and clinical outcomes were collected. Neighborhood socioeconomic variables were obtained at the census tract level from the 2018 American Community Survey. Relationships between neighborhood median income and clinical outcomes were evaluated using multivariate logistic regression models, controlling for patient age, sex, race, Charlson Comorbidity Index, obesity, smoking status, and living environment.Key ResultsBlack patients lived in significantly poorer neighborhoods than White patients (median income: $34,758 (24,531–56,095) vs. $63,317 (49,850–85,776), p < 0.001) and were more likely to have Medicaid insurance (19.4% vs. 11.2%, p < 0.001). Patients from neighborhoods with lower median income were significantly more likely to require IMV (lowest quartile: 25.4%, highest quartile: 16.0%, p < 0.001) and ICU admission (35.2%, 19.9%, p < 0.001). After adjusting for age, sex, race, and comorbidities, higher neighborhood income ($10,000 increase) remained a significant negative predictor for IMV (OR: 0.95 (95% CI 0.91, 0.99), p = 0.02) and ICU admission (OR: 0.92 (95% CI 0.89, 0.96), p < 0.001).ConclusionsNeighborhood disadvantage, which is closely associated with race, is a predictor of poor clinical outcomes in COVID-19. Measures of neighborhood disadvantage should be used to inform policies that aim to reduce COVID-19 disparities in the Black community.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11606-020-06527-1.KEY WORDS: COVID-19, disparities, disadvantage, socioeconomic status, race  相似文献   
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Hepatitis E virus (HEV) is implicated in many outbreaks of viral hepatitis in the Indian subcontinent. The conventional diagnosis of such outbreaks rests on the detection of anti‐HEV IgM antibodies. However, IgM antibodies develop after 4–5 days of infection. An early‐diagnostic marker is imperative for timely diagnosis of the outbreak and also initiation of control measures. This study aimed to determine the use of hepatitis E virus antigen detection as an early diagnostic marker in an outbreak in comparison to anti‐HEV IgM and RT‐PCR analyses. Forty samples were collected during a suspected outbreak of viral hepatitis due to HEV. A total of 36 samples were positive for one or more HEV markers. The positivity for anti‐HEV IgM, HEV antigen, and RT‐PCR was 91.6%, 69.4%, and 47.2% respectively. RT‐PCR and HEV antigen detection gave the highest positive results (100%) in the first 3 days of illness. Positive HEV PCR declined to 54% by Days 4–7, whereas HEV antigen and IgM detection were 88% and 100%, respectively. Sequencing of representative HEV samples indicated that the strains responsible for this outbreak belonged to genotype I, subtype 1a. HEV antigen was found to be an early diagnostic marker of acute infection. HEV antigen was detected in three additional cases in the early phase (1–3 days), and they had no detectable anti‐HEV IgM antibodies. These three samples were also positive for HEV RNA. After Day 7, anti‐HEV IgM was the main diagnostic indicator of infection. J. Med. Virol. 85:823–827, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
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Background

Retroclival hematoma (RCH) is a rare occurrence. The hemorrhage is usually small and hidden and can be easily missed on CT scan. Here, we report the association of a RCH with an odontoid fracture.

Methods

Case report and review of the literature.

Results

We describe a case of a 75-year-old man with a history of squamous cell carcinoma of the tongue base, treated with chemo-radiation. He was on warfarin for atrial fibrillation. He presented to the hospital 6 weeks after falling from standing height, with headache, neck pain, and stiffness. Clinical examination did not show any focal neurologic deficits. INR measured 4 days before admission was 6.0, but therapeutic at 2.4 on the day of admission. CT scan of the head showed a RCH. CT angiogram of the neck unexpectedly showed a type II odontoid fracture with instability of the upper cervical spine and extension of the hematoma to the upper cervical spine. Anticoagulation was reversed with factor IX complex (Bebulin). He underwent C1–C2 fusion without any complications. The immediate post-operative period was unremarkable. Unfortunately, he succumbed to airway obstruction due to mucus plugging 14 days into hospitalization.

Conclusions

In the appropriate clinical setting, when a RCH is found, further imaging should be considered to rule out fracture of the cervical spine. Odontoid fractures can lead to compression of the spinal cord or lower medulla. To prevent neurologic injury and subsequent complications, prompt recognition of type II odontoid fracture should lead to immediate spine stabilization.  相似文献   
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