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1.
Epithelial hyperplasia and metaplasia are common features of inflammatory and neoplastic disease, but the basis for the altered epithelial phenotype is often uncertain. Here we show that long-term ciliated cell hyperplasia coincides with mucous (goblet) cell metaplasia after respiratory viral clearance in mouse airways. This chronic switch in epithelial behavior exhibits genetic susceptibility and depends on persistent activation of EGFR signaling to PI3K that prevents apoptosis of ciliated cells and on IL-13 signaling that promotes transdifferentiation of ciliated to goblet cells. Thus, EGFR blockade (using an irreversible EGFR kinase inhibitor designated EKB-569) prevents virus-induced increases in ciliated and goblet cells whereas IL-13 blockade (using s-IL-13Ralpha2-Fc) exacerbates ciliated cell hyperplasia but still inhibits goblet cell metaplasia. The distinct effects of EGFR and IL-13 inhibitors after viral reprogramming suggest that these combined therapeutic strategies may also correct epithelial architecture in the setting of airway inflammatory disorders characterized by a similar pattern of chronic EGFR activation, IL-13 expression, and ciliated-to-goblet cell metaplasia.  相似文献   
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We studied a group of six patients with clinical, radiological, and/or manometric features of severely abnormal gastrointestinal motility. Symptoms suggestive of esophageal, small bowel, or colonic involvement were present from 1 1/2 to 40 years. All patients had elevated antinuclear antibody (ANA) titers. None had clinical or radiographic features suggestive of progressive systemic sclerosis or other connective tissue diseases. Two patients had pathologic examinations of intestinal specimens, and these did not show changes suggestive of progressive systemic sclerosis. We conclude that patients with severe gastrointestinal motility disorders can have elevated ANA titers without features of progressive systemic sclerosis or other connective tissue diseases.This study was supported by the National Institutes of Health grant AM 25965 and grant RR 59 from the General Research Centers Program, Division of Research Resources, National Institutes of Health.  相似文献   
4.

Aims/Introduction

The purpose of the present study was to examine glycemic control in suboptimally controlled type 2 diabetes provided by a structured education group using the Diabetes Conversation Map™ (CM™) vs usual care in a university-based hospital primary care clinic.

Materials and Methods

This was a randomized, pragmatic clinical trial. Patients with type 2 diabetes were randomly assigned to structured education or usual care groups. The primary outcome was the difference in the mean change of glycated hemoglobin (HbA1c) from baseline to 12 months. Secondary outcomes included the percentage achieving therapeutic HbA1c goal and self-behavioral changes.

Results

A total of 245 patients were randomly assigned to two groups (CM™ group n = 121; usual care group, n = 116). The absolute reduction of HbA1c was significantly greater in the CM™ group at 3 and 6 months (Δ = −0.59% and Δ = −1.13%, P < 0.01), but the difference was no longer statistically significant at 9 and 12 months (Δ = −0.43% and Δ = −0.49%), based on an intention-to-treat analysis. A per-protocol analysis showed the significant change was maintained at 12 months (Δ = −0.67%). In the intervention group, greater percentages of patients achieved their American Association of Diabetes Educators Self-Care Behaviours™ framework (AADE7) behavioral goals at 3 months, in particular being active, problem-solving, reducing risk and health coping.

Conclusions

In type 2 diabetic patients with suboptimally controlled glucose, there were greater improvements in glucose control and self-care behavioral goals in those who underwent the CM™ education program compared with outcomes achieved in patients receiving usual care.  相似文献   
5.
BACKGROUND: The clinical significance of colorectal wall thickening (CRWT) in patients undergoing abdominal computed tomography (CT) has not yet been definitively established. OBJECTIVES: To compare alleged findings on abdominal CT with those of a follow-up colonoscopy. METHODS: Ninety-four consecutive patients found to have large-bowel abnormalities on abdominal CT were referred for colonoscopy. Of these patients, 48 were referred for a suspected colorectal tumour and 46 for CRWT. Colonoscopy was performed and findings were compared. RESULTS: Of the 48 suspected colorectal tumours, 34 were determined to be neoplastic lesions on colonoscopy. Of these, 26 were malignant and eight were benign. Colonoscopy revealed no abnormality in 30 of 46 patients with CRWT as a solitary finding, and revealed some abnormality in 16 patients (12 had diverticular disease, four had benign neoplastic lesions). CONCLUSIONS: CRWT as an incidental and solitary finding on CT should not be regarded as a pathology prompting a colonoscopy. Approximately two-thirds of the patients had a normal colonoscopy and the remaining patients had benign lesions (12 had diverticular disease and four had benign neoplastic lesions). However, many of these patients seem to warrant colonoscopy regardless of CT findings, particularly patients who have a family history of colorectal cancer, have positive fecal occult blood test results or who are older than 50 years of age.  相似文献   
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Despite the high clinical impact of established and emerging respiratory viruses, some critical aspects of the host response to these pathogens still need to be defined. In that context, we aimed at two major issues: first, what are the innate immune mechanisms that control common respiratory viral infections; and second, whether these mechanisms also cause long-term airway disease. Using a mouse model of viral bronchiolitis, we found that antiviral defense depends at least in part on a network of mucosal epithelial cells and macrophages specially programmed for immune-response gene expression. When this network is compromised, the host is highly susceptible to infection, but network components can be engineered to provide increased resistance to infection. Similar alterations appear in asthma and chronic bronchitis/chronic obstructive pulmonary disease, suggesting that evolving attempts to improve antiviral defense may also lead to inflammatory airway disease. Indeed, in genetically susceptible mice, respiratory paramyxoviruses cause a "hit and run" phenomenon that is manifested by the development of a permanent airway disease phenotype long after the infection has cleared. The phenotype can be segregated into individual traits to achieve more precise definition of just how viruses reprogram host behavior. Identifying specific components of the mucosal immune system that manifest an aberrant antiviral response may thereby allow for adjusting this response to improve acute and chronic outcomes after viral infection.  相似文献   
8.
Cancer is often accompanied by worsening of the patient’s iron profile, and the resulting anemia could be a factor that negatively impacts antineoplastic treatment efficacy and patient survival. The first line of therapy is usually based on oral or intravenous iron supplementation; however, many patients remain anemic and do not respond. The key might lie in the pathogenesis of the anemia itself. Cancer-related anemia (CRA) is characterized by a decreased circulating serum iron concentration and transferrin saturation despite ample iron stores, pointing to a more complex problem related to iron homeostatic regulation and additional factors such as chronic inflammatory status. This review explores our current understanding of iron homeostasis in cancer, shedding light on the modulatory role of hepcidin in intestinal iron absorption, iron recycling, mobilization from liver deposits, and inducible regulators by infections and inflammation. The underlying relationship between CRA and systemic low-grade inflammation will be discussed, and an integrated multitarget approach based on nutrition and exercise to improve iron utilization by reducing low-grade inflammation, modulating the immune response, and supporting antioxidant mechanisms will also be proposed. Indeed, a Mediterranean-based diet, nutritional supplements and exercise are suggested as potential individualized strategies and as a complementary approach to conventional CRA therapy.  相似文献   
9.

Background

Electrical stimulation of the lower esophageal sphincter (LES) has been shown to improve outcomes in patients with gastroesophageal reflux disease (GERD) at 2 years. The aim of the study was to evaluate the safety and efficacy of LES stimulation in the same cohort at 3 years.

Methods

GERD patients with partial response to PPI, with % 24-h esophageal pH < 4.0 for >5 %, with hiatal hernia <3 cm and with esophagitis ≤LA grade C were treated with LES stimulation in an open-label 2-year trial. All patients were on fixed stimulation parameter of 20 Hz, 220 μs, 5 mA delivered in twelve, 30-min sessions. After completing the 2-year open-label study, they were offered enrollment into a multicenter registry trial and were evaluated using GERD-HRQL, symptom diaries and pH testing at their 3-year follow-up.

Results

Fifteen patients completed their 3-year evaluation [mean (SD) age = 56.1 (9.7) years; men = 8] on LES stimulation. At 3 years, there was a significant improvement in their median (IQR) GERD-HRQL on electrical stimulation compared to both their on PPI [9 (6–10) vs. 1 (0–2), p = 0.001] and off PPI [22 (21–24) vs. 1 (0–2), p < 0.001]. Median 24-h distal esophageal acid exposure was significantly reduced from [10.3 (7.5–11.6) % at baseline vs. 3 (1.9–4.5) %, p < 0.001] at 3 years. Seventy-three % (11/15) patients had normalized their distal esophageal acid exposure at 3 years. Remaining four patients had improved their distal esophageal acid exposure by 39–48 % from baseline. All but four patients reported cessation of regular PPI use (>50 % of days with PPI use); three had normal esophageal pH at 3 years. There were no unanticipated device- or stimulation-related adverse events or untoward sensation reported during the 2- to 3-year follow-up.

Conclusion

LES-EST is safe and effective for treating patients with GERD over long-term, 3-year duration. There was a significant and sustained improvement in esophageal acid exposure and reduction in GERD symptoms and PPI use. Further, no new GI side effects or adverse events were reported.
  相似文献   
10.
4‐Alkyloxy‐3,5‐bis(hydroxymethyl)phenylacetylenes with eight types of alkyl groups were synthesized and polymerized with a chiral catalytic system. We found that the length of the alkyl groups played a very important role in achieving helix‐sense‐selective polymerization. Five helix‐sense‐selective polymerizations were achieved resulting in polymers with alkyl groups whose chain length was longer than six. We think that the longer ‐ chain alkyl groups prevented the polymers from becoming insoluble by forming intermolecular hydrogen bonds between the hydroxyl groups, and stabilized their one‐handed helical structure by promoting the formation of intramolecular hydrogen bonds.

  相似文献   

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