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Background The patient interval—the time patients wait before consulting their physician after noticing cancer symptoms—contributes to diagnostic delays. We compared anticipated help-seeking times for cancer symptoms and perceived barriers to help-seeking before and after the coronavirus pandemic.Methods Two waves (pre-Coronavirus: February 2020, N = 3269; and post-Coronavirus: August 2020, N = 1500) of the Spanish Onco-barometer population survey were compared. The international ABC instrument was administered. Pre–post comparisons were performed using multiple logistic and Poisson regression models.Results There was a consistent and significant increase in anticipated times to help-seeking for 12 of 13 cancer symptoms, with the largest increases for breast changes (OR = 1.54, 95% CI 1.22–1–96) and unexplained bleeding (OR = 1.50, 1.26–1.79). Respondents were more likely to report barriers to help-seeking in the post wave, most notably worry about what the doctor may find (OR = 1.58, 1.35–1.84) and worry about wasting the doctor’s time (OR = 1.48, 1.25–1.74). Women and older individuals were the most affected.Conclusions Participants reported longer waiting times to help-seeking for cancer symptoms after the pandemic. There is an urgent need for public interventions encouraging people to consult their physicians with symptoms suggestive of cancer and counteracting the main barriers perceived during the pandemic situation.Subject terms: Cancer epidemiology, Cancer screening, Signs and symptoms, Public health, Diagnosis  相似文献   
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Background: Fungi growing on wood cause deterioration of stored food materials or discoloration of the wood itself, and the search for new and safe bioagents is recently needed. Methods: Essential oils (EOs) from aerial parts from Mentha longifolia L. and Citrus reticulata L., analyzed by gas chromatography-mass spectrometry (GC-MS), were tested for their antifungal activity by the vapor method against four common fungi, Aspergillus flavus, A. niger, A. fumigatus, and Fusarium culmorum, and confirmed by SEM examination as the oils applied on wood samples. Results: The most abundant compounds identified in the EO from M. longifolia were menthone and eucalyptol; in C. reticulata EO, they were β-caryophyllene, β-caryophyllene oxide, and β-elemene. EOs from M. longifolia and C. reticulata, at 500 and 250 µL/mL, showed potent antifungal activity against A. flavus and A. fumigatus, with 100% fungal mycelial inhibition growth (FMIG). C. reticulata and M. longifolia EOs, at 125 µL/mL, observed FMIG values of 98% and 95%, respectively, against A. fumigatus. M. longifolia EO, at 500 and 250 µL/mL, showed potent activity against A. niger, with 100% FMIG. F. culmorum completely inhibited (100% FMIG) EOs from M. longifolia and C. reticulata applied at 500 µL/mL. Pinus roxburghii Sarg. Wood, treated with M. longifolia at 125 µL/mL, showed inhibition zone values of 7.33 and 21.33 mm against A. flavus and A. niger, respectively. Conclusions: Both oils possessed good wood-biofungicide activity with the vapor method, as clearly shown by the SEM examination. These activities suggest their possible use as natural wood preservatives.  相似文献   
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BACKGROUND: Esophagoscopy with a portable battery-powered endoscope could provide a safe, inexpensive, and minimally invasive way to screen for Barrett's esophagus or esophageal varices. The use of such an instrument in an unsedated fashion has not been previously evaluated. METHODS: Patients referred for an EGD were recruited to undergo an additional examination with the battery-powered endoscope before EGD. In phase 1, (n = 42) patients received conscious sedation before the battery-powered endoscopic examination. In phase 2, (n = 56) patients were not sedated and were given the option of a peroral (n = 43) or transnasal (n = 13) endoscopy. Examiners were blinded to patient history and procedure indications. Esophageal findings, ease of intubation, optical quality, and patient comfort for the battery-powered endoscope and standard EGD were recorded by the endoscopist. RESULTS: Ninety-eight patients (60 men, 38 women, mean age 53 years) were recruited. The sensitivity for detecting Barrett's esophagus, esophageal tumors, and esophageal varices was 54.5%, 66.7%, and 80%, respectively. Ease of intubation and patient comfort as perceived by the endoscopist were not significantly different between the battery-powered endoscope and EGD. Optical quality was ranked as less than 4 (on a 5-point scale with 5 = standard EGD and 1 = poor) in 42% of battery-powered endoscopic examinations. There were no complications. CONCLUSION: The accuracy of esophageal examination with a 3.1-mm endoscope is substantially inferior to standard EGD. Thus, the battery-powered endoscope would not be useful for screening patients for Barrett's esophagus or varices unless improvements in optical quality and visualization are made.  相似文献   
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Development of Junctions During Differentiation of Lens Fibers   总被引:15,自引:1,他引:15       下载免费PDF全文
Throughout the differentiation of eye lens epithelium into fibers, an extensive system of intercellular junctions develops. The junctional assembly is initially characterized by the accumulation of 9.0-nm intramembranous particles, forming linear rows in the matching plasma membranes of adjoining fibers. At the final stage of the fiber differentiation, the junctional particles are assembled in geometrically packed arrays. The formation of linear rows and bidimensional lattices of intramembranous particles probably favors reciprocal recognition of cell surfaces and specific cell-to-cell interlocking. Moreover, the existence of a rather rigid lipid core of the plasma membrane of eye lens fiber may promote the clustered distribution of intramembranous particles and facilitate the junctional assembly.  相似文献   
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The aims of this study were to evaluate the clinical characteristics of HIV-negative patients affected by lymphoproliferative disorders (LPD) who developed progressive multifocal leukoencephalopathy (PML), to delineate the risk factors, and to analyze whether the new antineoplastic therapies are changing the natural history of this infectious disease. We retrospectively analyzed 46 cases with confirmed LPD-associated PML published from 1958 to 2004. Patients were stratified according to two different time periods: group A included patients diagnosed before 1989, and group B included patients diagnosed since 1990, after introduction of purine analogues. Group A patients (n = 22) had received alkylating agents and/or radiotherapy, and the majority (63.6%) had advanced Hodgkin disease. At univariate analysis, uncontrolled Hodgkin disease was the only risk factor for PML. In group B patients (n = 24), the most frequent treatments received were purine analogues (58.3%) and high-dose therapy with hematopoietic stem cell transplantation (33.3%; HDT/HSCT). B-cell chronic lymphocytic leukemia (45.8%) and aggressive non-Hodgkin lymphoma (24.9%) were the most frequent underlying LPDs. Patients treated with purine analogues were more likely to have active LPD, lower CD4 cell counts, and to be older and male than were HSCT recipients. The median interval from purine analogues or HDT/HSCT to PML was 11 months. In HDT/HSCT recipients, this interval was delayed for 10 months when peri-transplantation rituximab was used. Univariate analysis identified age >55 years, male sex, and CD4 cell counts 相似文献   
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Neonatal lupus erythematosus (NLE) is an infrequent disease in newborns caused by the transplacental passage of maternal Anti-Ro/SSA, Anti-La/SSB and/or Anti-U1 RNP antibodies. The most common manifestations are cutaneous and cardiac. We carried out a retrospective study of cases of NLE diagnosed in the last 10 years at the Hospital Universitario Insular in Gran Canaria. Complete data was obtained for 4 patients. Three cases had circulating Anti-Ro antibodies in the mother and in the newborns, while in the fourth case they were Anti-RNP. Two mothers were diagnosed with systemic lupus, one with mixed connective tissue disease and the other with leucocytoclastic vasculitis. The skin lesions consisted of urticaria-like and desquamative lesions. One patient presented with ulceration. The histological study of the urticaria-like lesions showed a non-specific perivascular infiltrate; the desquamative lesions were consistent with subacute lupus erythematosus.  相似文献   
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BACKGROUND: Unsedated esophagoscopy with small-diameter endoscopes is generally well tolerated but of limited sensitivity for the diagnosis of esophageal mucosal disease. This study evaluated the sensitivity of esophagoscopy performed with new 4-mm diameter prototype battery-powered and video endoscopes. Patient tolerance for an unsedated examination with the 4-mm endoscopes was assessed and the performance characteristics of the battery-powered and video 4-mm endoscopes were compared. METHODS: Patients referred for EGD were recruited to undergo an additional examination with a 4-mm endoscope. A prototype 60-cm long, 4-mm diameter battery-powered fiberoptic esophagoscope was used in the first 24 patients and a prototype 60-cm long, 4-mm diameter video esophagoscope in the next 27 patients. Examiners who were unaware of patient history and procedure indications recorded esophageal findings, ease of intubation, optical quality (5-point visual scale), and time for examination of the esophagus and then recorded esophageal findings after the standard EGD. RESULTS: The sensitivity, specificity, and accuracy for identification of Barrett's esophagus was 100%; overall sensitivity, accuracy, and specificity for detecting esophageal lesions were, respectively, 91%, 98%, and 99%. Patient tolerance (assessed by symptom scores for choking, pain, and discomfort) and acceptability of unsedated esophagoscopy with the 4-mm diameter instruments were significantly better than in a historical group of patients examined with a 3-mm diameter endoscope. The optical quality of video endoscope was rated as superior to that of battery-powered endoscope, and esophageal examination was performed significantly quicker with the video versus the battery-powered endoscope (68 vs. 137 seconds; p = 0.001). CONCLUSIONS: Unsedated esophagoscopy with 4-mm diameter endoscopes may be an alternative to EGD for screening for Barrett's esophagus. Given the current state of endoscopic technology, a minimum diameter of 4 mm is required for satisfactory esophageal imaging.  相似文献   
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The aim of the present study is the design and development of thermoresponsive nanogels based on ulvan, a sulphated heteropolysaccharide of algal origins with unique biological and chemical properties. Hybrid nanogels are successfully synthesized by means of UV‐initiated radical copolymerization of N‐vinylcaprolactam with an ulvan derivate as a novel crosslinker. In nanogels, the ulvan‐grafted poly(N‐vinylcaprolactam) chains represent the thermoresponsive component. The most promising candidates, selected after a thorough physical–chemical characterization of nanogels in terms of size and responsivity to thermal variation at physiological conditions, are loaded with bovine serum albumin (BSA) as model bioactive compound. The developed nanogels display BAS loading efficiency values similar to those obtained by using synthetic crosslinkers, and thus indicating the suitability of the developed ulvan‐acrylate to act as novel macromolecular crosslinker for thermoresponsive nanogels preparation.  相似文献   
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