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Cough and paradoxical vocal fold motion 总被引:8,自引:0,他引:8
Kenneth W. Altman MD PhD C. Blake Simpson MD Milan R. Amin MD Mona Abaza MD Ron Balkissoon MD Roy R. Casiano MD 《Otolaryngology--head and neck surgery》2002,127(6):501-511
OBJECTIVES: The differential diagnosis and treatment of patients with chronic cough, paradoxical vocal fold motion, and disordered breathing can be a challenge to most practicing otolaryngologists. Tracheobronchial (ie, asthma, bronchitis, and tracheal stenosis), laryngeal (ie, vocal fold paralysis and neoplasms), and rhinologic (ie, allergies and rhinosinusitis) etiologies are commonly diagnosed and treated effectively. However, occasionally one is faced with patients who are refractory to medical treatment and have no obvious rhinologic, laryngeal or pulmonary cause. STUDY DESIGN AND SETTING: We conducted a review of the literature. METHODS: We present a thorough review of the current medical literature exploring the complex neurologic mechanisms involved in the production of cough and the relationship between gastroesophageal reflux disease, vagal neurapathy, and paradoxical vocal fold motion. RESULTS: The diagnosis and successful treatment of chronic cough can be complex. It requires a thorough understanding of the neurologic mechanisms behind cough excitation and suppression. Successful treatment strategies include aggressive management of the patient's reactive airway disease, gastroesophageal reflux disease, and, in select cases, paradoxical vocal fold motion. This may involve a well-coordinated effort among pulmonologists, otolaryngologists, gastroenterologists, and speech pathologists. CONCLUSION: Gastroesophageal reflux disease, vagal neuropathy, and paradoxical vocal fold motion are additional causes of chronic cough and disordered breathing that need to be considered, in the absence of obvious laryngotracheal and/or rhinologic pathology. A high index of suspicion is essential in making the diagnosis and formulating an effective multidisciplinary treatment plan for these patients. 相似文献
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Enyioma N OBINECHE Michael PT GILLETT Abdishakur ABDULLE Mustapha SULAIMAN Mona AL-ROKHAIMI 《Nephrology (Carlton, Vic.)》2002,7(3):115-120
SUMMARY: In patients with chronic renal failure (CRF), hyperleptinaemia has been widely reported, but the exact mechanisms leading to elevated leptin levels are unclear. Impaired renal clearance of leptin and the influence of other hormones may be important. In this study, we measured serum leptin levels in 150 patients on haemodialysis, peritoneal dialysis or in the predialysis phase of CRF. Furthermore, we measured plasma levels of insulin, growth hormone (GH) and insulin-like growth factor 1 (IGF-1), as well as plasma levels of triacylglycerols and total low density lipoprotein (LDL)- and high density lipoprotein (HDL)-cholesterol. We observed significantly elevated levels of leptin, particularly in female patients, and leptin was shown to correlate significantly with insulin, total and LDL-cholesterol and log triacylglycerols. Leptin was inversely correlated with GH concentrations, but was not correlated with IGF-1 levels. Despite the multiple correlations established between leptin levels and other variables, only hyperinsulinaemia in CRF seems to be important as a determinator of leptin levels. 相似文献
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Moussa Ndong Machiko Kazami Tsukasa Suzuki Mariko Uehara Shin-ichi Katsumata Hirohumi Inoue Ken-Ichi Kobayashi Tadahiro Tadokoro Kazuharu Suzuki Yuji Yamamoto 《Nutrition Research》2009,29(9):640-647
Iron deficiency (ID) is one of the most commonly known forms of nutritional deficiencies. Low body iron is thought to induce neurologic defects but may also play a protective role against cancer development by cell growth arrest. Thus, ID may affect cellular pathways controlling cell growth and proliferation, the mechanism of which is still not fully understood. The serine/threonine protein kinase Akt and its downstream target, the mammalian Target of Rapamycin (mTOR), is known to play a crucial role in the regulation of cell growth and survival. Therefore, we hypothesized that Akt/mTOR pathway could be influenced by ID. Three-week-old male Wistar-strain rats were divided into 3 groups and the 2 groups had free access to a control diet (C group) or an iron-deficient diet (D group). The third group (PF group) were pair-fed the control diet to the mean intake of the D group. After 4 weeks, rats were killed and their brains were sampled. In separate experiments, COS-1 cells were cultured with or without the iron chelator deferoxamine. Western blots of brain samples and COS-1 lysates were used to analyze the expression and phosphorylation state of Akt, TSC2, mTOR, and S6 kinase proteins implicated in the Akt/mTOR pathway. Using 2 different ID models, we show for the first time that iron deficiency depresses Akt activity in rats and in COS-1 cells, leading to a decrease in mTOR activity. 相似文献
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Interactions Between Cytomegalovirus, Human Herpesvirus-6, and the Recurrence of Hepatitis C After Liver Transplantation 总被引:1,自引:0,他引:1
Atul Humar Deepali Kumar Janet Raboud Angela M. Caliendo George Moussa Gary Levy Tony Mazzulli 《American journal of transplantation》2002,2(5):461-466
Recurrence of hepatitis C (HCV) following liver transplantation is common. Herpesvirus reactivation following transplant may have an immunomodulatory effect resulting in increased HCV replication. We studied whether cytomegalovirus (CMV) and human herpesvirus-6 (HHV-6) may be associated with HCV recurrence and viral load after transplant. We prospectively followed 66 HCV liver-transplant recipients with serial viral load testing for CMV and HHV-6. Infection and viral load were correlated with the development of biopsy-proven HCV recurrence and HCV viral loads. Histologic recurrence of HCV occurred in 41/66 (62.1%) patients. In the primary analysis, CMV infection and disease, and HHV-6 infection were not associated with HCV recurrence. Peak CMV and HHV-6 viral loads were not significantly different in patients with and without recurrence. No correlation was observed between HCV viral loads at 1 and 3 months post-transplant and peak HHV-6 or CMV viral loads. In a subgroup analysis, HHV-6 infection was associated with the development of more severe recurrence (hepatitis and/or fibrosis score > or = 2) (p = 0.01). Also, fibrosis scores at last follow up were higher in patients with CMV disease (1.67 vs. 0.56; p = 0.016) and in patients with HHV-6 infection (1.18 vs. 0.55; p = 0.031). In conclusion, HHV-6 and CMV infection and viral load were not associated with increased overall rates of HCV recurrence or HCV viral load after liver transplantation but may be associated with more severe forms of recurrence. 相似文献
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M. Sand T. Gambichler G. Moussa F. G. Bechara D. Sand P. Altmeyer K. Hoffmann 《Skin research and technology》2006,12(2):114-118
BACKGROUND/AIMS: It has recently been proposed that the refractive index (RI) measured by means of optical coherence tomography (OCT) may be a valid measure for hydration of skin. In this pilot study, using OCT in vivo, we aimed to investigate the interday variability of RI measurements and acute changes of RI following the application of a moisturizer. METHODS: Twenty healthy Caucasian volunteers were investigated on their forearms using a commercially available OCT system (SkinDex 300, ISIS optronics GmbH, Mannheim, Germany) fitted with an integrated algorithm for the evaluation of the RI. The interday repeatability of the OCT method was determined performing symmetrical measurements on both forearms on day 1, 5, 9, and 13. In order to investigate the acute effect of a moisturizer on RI, OCT assessments were performed before and 10 min after the application of an aqueous lotion with a lipophilic phase. As a control, the contralateral site was investigated in the same way, except for the use of distilled water instead of the lotion. RESULTS: Assessments of interday variability revealed insignificant (P>0.05) variances between the four measurement times as expressed in very small repeatability coefficients (right arm: 0.039; left arm 0.053) and small coefficients of variance (right arm: 1.02%; left arm: 1.38%). With regard to the RIs measured over time, we could not observe significant (P>0.05) differences between the two symmetrical anatomic sites (mean+/-SD of RI: 1.3893+/-0.0142 (right arm); 1.3875+/-0.0192 (left arm)). The acute effect of the moisturizer was indicated by a significant decrease of the RI 5 min after the application of the lotion (1.399+/-0.01 vs. 1.387+/-0.02; difference between means: 0.012; P=0.033; 95% confidence interval: 0.001-0.0023). However the control site treated with distilled water did not show significant differences between the two measurement times (1.387+/-0.013 vs. 1.391+/-0.023; difference between means: -0.004; P=0.57; 95% confidence interval: -0.019-0.011). CONCLUSIONS: In this pilot study, we have demonstrated that RI evaluation via OCT is a promising technique that may be used for the assessment of skin hydration in vivo. However, the direct comparison of OCT with standard methods, ideally such as nuclear magnetic resonance spectroscopy, is necessary. 相似文献
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Kiran Chang Mona Sarkiss Kyoung Sook Won Joseph Swafford Lyle Broemeling Isis Gayed 《Journal of nuclear medicine》2007,48(3):344-348
Cancer patients frequently have anemia or an altered coagulation state that may affect their risk stratification for perioperative cardiac events. We performed this study to investigate the incidence of perioperative cardiac events in cancer patients who had abnormal stress myocardial perfusion imaging (MPI) results versus cancer patients with normal MPI results. METHODS: We included 394 consecutive cancer patients with normal (n = 201) or abnormal (n = 193) results on MPI studies performed for preoperative risk stratification. MPI was performed within 6 mo before each patient's scheduled operation. All the patients had surgical procedures requiring general anesthesia, except for 18 who had endoscopic or colonoscopic procedures. We retrospectively reviewed their data for the incidence of major cardiac events intraoperatively and for 1 mo postoperatively. We collected data on their cancer type, risk factors for coronary artery disease, MPI findings, risk of operation, and intraoperative or postoperative major cardiac events, which included death, myocardial infarction (MI), and congestive heart failure (CHF). RESULTS: The patients with abnormal MPI results included 97 with ischemia, 80 with scarring, and 16 with mixed scarring and ischemia. The mean left ventricular ejection fraction and end-diastolic volume were 63.8% +/- 9.8% and 82.0 +/- 53.5 mL in the normal MPI group versus 52.1% +/- 13.1% and 118.1 +/- 53.4 mL in the abnormal-MPI group (P < 0.001). There were 9 major intraoperative or postoperative cardiac events (4.7%) in the patients with abnormal MPI results and none in the patients with normal MPI results (P = 0.001). These major events consisted of 3 deaths, 2 acute MIs, 1 non-Q-wave MI, and 3 cases of CHF. Four of these patients had only scarring on their MPI studies, 3 had ischemia, and 2 had scarring and ischemia. CONCLUSION: Normal MPI results have a high negative predictive value for perioperative cardiac events in cancer patients. Abnormal MPI results, whether demonstrating scarring or ischemia, should prompt appropriate perioperative management in patients with cancer to minimize major cardiac events. 相似文献