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41.
Although the mechanisms of nocturnal worsening of pulmonary function in asthmatics have not been entirely established, airway inflammation is felt to be a major factor in disease severity. Consequently, to determine whether changes in bronchoalveolar lavage (BAL) fluid cellular components and their functions are related to nocturnal airway obstruction, we performed BAL at 4:00 A.M. and at 4:00 P.M. in asthma subjects with (n = 5) and without (n = 10) nocturnal asthma. No significant changes were observed from 4:00 P.M. to 4:00 A.M. in the concentration of total cells or the percentage or concentration of eosinophils or neutrophils in BAL fluid from subjects with or without nocturnal asthma. However, superoxide anion generation by air-space cells from subjects with nocturnal asthma was significantly greater at 4:00 A.M. than at 4:00 P.M. (6.9 +/- 1.7 versus 1.8 +/- 0.5 nmol/500K cells/h, p less than 0.05). Moreover, superoxide production at 4:00 A.M. was greater in subjects with than in those without nocturnal asthma (6.9 +/- 1.7 versus 2.2 +/- 0.6, p less than 0.02). Furthermore, in our group of asthmatics, the change in generation of superoxide anion from 4:00 P.M. to 4:00 A.M. was significantly correlated with the change in FEV1 (r = -0.71, p less than 0.01). We conclude that the development of nocturnal airway obstruction in asthma is associated with enhanced production of oxygen radicals by air-space cells. Because oxygen radicals can cause airway injury and thus enhance bronchial obstruction, it is possible that the release of these reactive compounds is causally associated with nocturnal asthma. 相似文献
42.
Aldosterone antagonists have been available for many decades for the treatment of hypertension, but their use has been mostly
limited to patients with classic primary aldosteronism or to combination products with hydrochlorothiazide to minimize risk
for hypokalemia. Recently, indications for aldosterone antagonists have been expanded to include congestive heart failure
and first-line treatment of mild-to-moderate hypertension. In addition, we have reported that spironolactone has significant
antihypertensive benefit when added to existing regimens in patients with resistant hypertension. This benefit was present
in patients with and without hyperaldosteronism and was additive to chronic renin-angiotensin blockade with angiotensin-converting
enzyme (ACE) inhibitors or angiotensinreceptor blockers (ARBs). Eplerenone, a selective aldosterone antagonist, avoids the
androgen and progesterone receptor-related adverse events that sometimes occur with spironolactone, such as breast tenderness,
gynecomastia, sexual dysfunction, and menstrual irregularities. In clinical trials, eplerenone has been shown to have antihypertensive
benefit in treating mild-to-moderate hypertension similar to other widely used classes of agents. With recent demonstrations
of benefit in multiple segments of the hypertensive population, aldosterone antagonists represent emerging opportunity for
controlling high blood pressure. 相似文献
43.
Patricia C. McMullen William O. Howie Nayna Philipsen Virletta C. Bryant Patricia D. Setlow Mona Calhoun Zakevia D. Green 《Archives of physical medicine and rehabilitation》2021,102(1):660-665
Electronic medical records (EMRs) and electronic health records (EHRs) have become essential systems by which nurse practitioners (NPs) communicate vital patient information to other members of the health care team as well as to patients. In this article we examine the important distinctions between EMRs and EHRs; review the genesis of these types of records; summarize applicable provisions of the Health Insurance Portability and Accountability Act from a recent legal case centered around NP utilization of EMRs and EHRs; address open patient access to medical information; and examine threats to security. Suggestions are offered on ways in which NPs can safeguard confidential patient information. 相似文献
44.
45.
Julio Fernandez-Mendoza Fan He Kristina Puzino Gregory Amatrudo Susan Calhoun Duanping Liao Alexandros N Vgontzas Edward Bixler 《Sleep》2021,44(1)
Study ObjectivesInsomnia with objective short sleep duration has been previously associated with adverse cardiometabolic health outcomes as well as poorer cognitive performance in otherwise noncognitively impaired adults. However, studies demonstrating an increased prevalence of cognitive impairment (CI) in this insomnia phenotype are lacking.MethodsWe analyzed data from Penn State Adult Cohort (N = 1,524; 48.9 ± 13.4 years; 53.4% women). Self-reported sleep difficulty was defined as normal sleep (n = 899), poor sleep (n = 453), and chronic insomnia (n = 172). Objective short sleep duration was defined as less than 6-h of sleep, based on in-lab, 8-h polysomnography. CI (n = 155) and possible vascular cognitive impairment (pVCI, n = 122) were ascertained using a comprehensive neuropsychological battery. Analyses adjusted for age, sex, race, education, body mass index, apnea/hypopnea index, smoking, alcohol, psychoactive medication, and mental and physical health problems.ResultsParticipants who reported poor sleep or chronic insomnia and slept objectively less than 6 hours were associated with a 2-fold increased odds of CI (OR = 2.06, 95% confidence limits [CL] = 1.15–3.66 and OR = 2.18, 95% CL = 1.07–4.47, respectively) and of pVCI (OR = 1.94, 95% CL = 1.01–3.75 and OR = 2.33, 95% CL = 1.07–5.06, respectively). Participants who reported poor sleep or chronic insomnia and slept objectively more than 6 hours were not associated with increased odds of either CI (OR = 0.72, 95% CL = 0.30–1.76 and OR = 0.75, 95% CL = 0.21–2.71, respectively) or pVCI (OR = 1.08, 95% CL = 0.42–2.74 and OR = 0.76, 95% CL = 0.16–3.57, respectively).ConclusionsInsomnia with objective short sleep duration is associated with an increased prevalence of CI, particularly as it relates to cardiometabolic health (i.e. pVCI). These data further support that this insomnia phenotype may be a more biologically severe form of the disorder associated with cardiovascular, cerebrovascular, and neurocognitive morbidity. 相似文献
46.
Nadimul Hoda Rajani BC Subhabrata Ghosh Sabitha KS Vasantha Dhara B Jayesh Nathani 《Medicina oral, patología oral y cirugía bucal》2021,26(1):e84
Background The study was performed with an aim to map the pattern of metastasis of squamous cell carcinomas of buccal mucosa to various cervical lymph node levels and analyze its correlation with primary tumor size and histo-pathological grading. Material and Methods 254 patients with squamous cell carcinoma of the buccal mucosa treated with surgery first approach were analyzed retrospectively. The tumor size was noted from pre-operative CT Scans and were divided into early and advanced tumors. The resected specimen was studied to note the histo-pathological grading of the squamous cell carcinoma and the metastatic deposits at various lymph node levels. Results Out of 254 patients (149 females, 105 males), 145 patients showed histo-pathologically proven metastatic deposits in one or more lymph nodes out of which there were 56 patients showing occult metastasis. 78/145 patients showed metastatic involvement of level IB and/or IA lymph nodes, 31 showed involvement of level II and/or I lymph nodes, 27 showed involvement of level III with or without involvement of level I and II and 9 showed metastasis to level IV and V lymph nodes with or without level I, II or III lymph nodes. Cervical lymph node metastasis had statistically significant association with tumor size with advanced tumors showing worse pattern of metastatic spread beyond level I and II lymph nodes. As the degree of differentiation of squamous cell carcinoma reduced, they were more prone for cervical metastasis with moderately and poorly differentiated squamous cell carcinoma showing higher involvement of level III, IV and V lymph nodes. Conclusions The majority of buccal mucosa cases showed metastasis to level I, II and III lymph nodes out of which level IB and/or IA was most frequently involved. Metastasis to level IV and V lymph nodes was rare and was seen especially in patients with advanced primary tumor and poor histo-pathologic differentiation. Key words:Oral squamous cell carcinoma (OSCC), cervical lymph node metastasis, histologic differentiation, locally advanced disease. 相似文献
47.
Eosinophils stimulate fibroblast DNA synthesis 总被引:9,自引:0,他引:9
Fibrosis complicates a number of chronic inflammatory diseases and occurs in some conditions following chronic hypereosinophilic syndromes. We assessed whether eosinophils might be a source of fibrogenic factors. Extracts of human and guinea pig cell populations enriched for eosinophils contained substances that stimulated tritiated thymidine incorporation by human fibroblasts. Supernatants derived from resting eosinophils and extracts prepared from eosinophil granules also contained fibrogenic factors. Our findings demonstrate a new potential role for eosinophils and suggest a causal relationship between tissue eosinophilia and scar formation in certain parasitic conditions. 相似文献
48.
Akagawa KS; Takasuka N; Nozaki Y; Komuro I; Azuma M; Ueda M; Naito M; Takahashi K 《Blood》1996,88(10):4029-4039
We previously showed that granulocyte-macrophage colony-stimulating factor (GM-CSF) and macrophage colony-stimulating factor (M-CSF) stimulate the differentiation of human monocytes into two phenotypically distinct types of macrophages. However, in vivo, not only CSF but also many other cytokines are produced under various conditions. Those cytokines may modulate the differentiation of monocytes by CSFs. In the present study, we showed that CD14+ adherent human monocytes can differentiate into CD1+relB+ dendritic cells (DC) by the combination of GM-CSF plus interleukin-4 (IL-4) and that they differentiate into tartrate-resistant acid phosphatase (TRAP)-positive osteoclast-like multinucleated giant cells (MGC) by the combination of M-CSF plus IL-4. However, the monocyte-derived DC were not terminally differentiated cells; they could still convert to macrophages in response to M-CSF. Tumor necrosis factor-alpha (TNF-alpha) stimulated the terminal differentiation of the DC by downregulating the expression of the M-CSF receptor, cfms mRNA, and aborting the potential to convert to macrophages. In contrast to IL-4, interferon-gamma (IFN-gamma) had no demonstrable effect on the differentiation of monocytes. Rather, IFN- gamma antagonized the effect of IL-4 and suppressed the DC and MGC formation induced by GM-CSF + IL-4 and M-CSF + IL-4, respectively. Taken together, these results provide a new aspect to our knowledge of monocyte differentiation and provide evidence that human monocytes are flexible in their differentiation potential and are precursors not only of macrophages but also of CD1+relB+DC and TRAP-positive MGC. Such a diverse pathway of monocyte differentiation may constitute one of the basic mechanisms of immune regulation. 相似文献
49.
Calhoun DA Jones D Textor S Goff DC Murphy TP Toto RD White A Cushman WC White W Sica D Ferdinand K Giles TD Falkner B Carey RM 《Hypertension》2008,51(6):1403-1419
Resistant hypertension is a common clinical problem faced by both primary care clinicians and specialists. While the exact prevalence of resistant hypertension is unknown, clinical trials suggest that it is not rare, involving perhaps 20% to 30% of study participants. As older age and obesity are 2 of the strongest risk factors for uncontrolled hypertension, the incidence of resistant hypertension will likely increase as the population becomes more elderly and heavier. The prognosis of resistant hypertension is unknown, but cardiovascular risk is undoubtedly increased as patients often have a history of long-standing, severe hypertension complicated by multiple other cardiovascular risk factors such as obesity, sleep apnea, diabetes, and chronic kidney disease. The diagnosis of resistant hypertension requires use of good blood pressure technique to confirm persistently elevated blood pressure levels. Pseudoresistance, including lack of blood pressure control secondary to poor medication adherence or white coat hypertension, must be excluded. Resistant hypertension is almost always multifactorial in etiology. Successful treatment requires identification and reversal of lifestyle factors contributing to treatment resistance; diagnosis and appropriate treatment of secondary causes of hypertension; and use of effective multidrug regimens. As a subgroup, patients with resistant hypertension have not been widely studied. Observational assessments have allowed for identification of demographic and lifestyle characteristics associated with resistant hypertension, and the role of secondary causes of hypertension in promoting treatment resistance is well documented; however, identification of broader mechanisms of treatment resistance is lacking. In particular, attempts to elucidate potential genetic causes of resistant hypertension have been limited. Recommendations for the pharmacological treatment of resistant hypertension remain largely empiric due to the lack of systematic assessments of 3 or 4 drug combinations. Studies of resistant hypertension are limited by the high cardiovascular risk of patients within this subgroup, which generally precludes safe withdrawal of medications; the presence of multiple disease processes (eg, sleep apnea, diabetes, chronic kidney disease, atherosclerotic disease) and their associated medical therapies, which confound interpretation of study results; and the difficulty in enrolling large numbers of study participants. Expanding our understanding of the causes of resistant hypertension and thereby potentially allowing for more effective prevention and/or treatment will be essential to improve the long-term clinical management of this disorder. 相似文献
50.
Emma Sprooten Cota Navin Gupta Emma E.M. Knowles D. Reese McKay Samuel R. Mathias Joanne E. Curran Jack W. Kent Jr Melanie A. Carless Marcio A. Almeida Thomas D. Dyer Harald H.H. Göring Rene L. Olvera Peter Kochunov Peter T. Fox Ravi Duggirala Laura Almasy Vince D. Calhoun John Blangero Jessica A. Turner David C. Glahn 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2015,168(8):678-686