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21.

PURPOSE

We aimed to determine the prevalence of paratracheal air cysts (PTACs) and the relationship of PTACs with emphysema and bronchiectasis through retrospective analysis of multidetector computed tomography (MDCT) findings.

METHODS

MDCT findings of 1027 consecutive patients who underwent routine thorax examination between January 2012 and January 2013 were evaluated retrospectively for the presence of PTACs. Localization of the PTACs, as well as their size, shape, and relationship with the trachea were examined. Presence of emphysema and bronchiectasis was recorded, and bronchiectasis severity index was calculated when present. We randomly selected 80 patients who had no visible PTACs as the control group. The findings of patients with and without PTACs were compared.

RESULTS

PTACs were determined in 82 of 1027 patients (8%), in 8.8% of females and 7.3% of males. The presence of PTACs was determined to be independent of gender (P = 0.361). Eighty-one PTACs (98.8%) were located in the right side of the trachea and 56.1% had a tracheal connection. The presence of PTACs significantly correlated with the presence and severity of bronchiectasis (P = 0.001 and P = 0.005 respectively). There was no significant relationship between the presence of PTACs and the presence of emphysema on CT images (P = 0.125).

CONCLUSION

The prevalence of PTACs was determined as 8% in this study. There was significant association between PTACs and bronchiectasis.Paratracheal air cysts (PTACs) are small collections of air adjacent to the trachea at the level of the thoracic inlet (1). Pathological diagnosis of PTACs in surgically confirmed cases includes tracheal diverticulum, lymphoepithelial cyst, and bronchogenic cyst (13). These cysts are covered with ciliary columnar epithelium and connected with the trachea (4). The majority of PTACs are reported as tracheal diverticula in the literature, due to their connection with the trachea (2). The thoracic inlet between the cartilage and muscle layers in right posterolateral wall of the trachea is the most common location for PTACs. A relationship may be seen between an isolated PTAC and the trachea l lumen (5). These lesions may cause recurrent infections by acting as a reservoir for secretions.Occasionally, PTACs can be confused with other causes of extraluminal air collections as laryngocele, pharyngocele, Zenker’s diverticulum, apical hernia of the lung, mediastinal air, apical paraseptal blebs, or bullae. To distinguish PTACs from other pathologies, its typical location in the right posterior paratracheal region at the thoracic inlet can be helpful: PTACs locate away from the lung pleura, communicate with the trachea and have rounded margins that can be differentiated from emphysematous changes (6).PTACs are usually discovered incidentally on thorax computed tomography (CT). They may be associated with a chronic cough or chronic obstructive pulmonary diseases (COPD). The reported prevalence of PTACs ranges from 0.75% to 8.1% (4, 68). There have been a limited number of studies reporting the incidence of PTACs related to COPD or emphysema as detected by CT, and the reported results are variable (4, 6, 811). The relationship between PTACs and pulmonary emphysema or bronchiectasis is still unclear. To our knowledge, no published study has evaluated the relationship between PTACs and bronchiectasis, using a bronchiectasis severity index and objective measures to determine the extent of bronchiectasis on CT images.The purpose of our study was to evaluate the prevalence and characteristics of PTACs, as well as their relationship with bronchiectasis and emphysema, on thorax CT scans.  相似文献   
22.
Chronic renal failure (CRF) is associated with oxidative stress that promotes production of reactive oxygen species (ROS). Melatonin, the chief secretory product of the pineal gland, was recently found to be a potent free radical scavenger and antioxidant. The aim of this study was to examine the role of melatonin in protecting the aorta, heart, corpus cavernosum, lung, diaphragm, and kidney tissues against oxidative damage in a rat model of CRF, which was induced by five of six nephrectomy. Male Wistar albino rats were randomly assigned to either the CRF group or the sham-operated control group, which had received saline or melatonin (10 mg/kg, i.p.) for 4 wk. CRF was evaluated by serum blood urea nitrogen (BUN) level and creatinine measurements. Aorta and corporeal tissues were used for contractility studies, or stored along with heart, lung, diaphragm, and kidney tissues for the measurement of malondialdehyde (MDA, an index of lipid peroxidation), protein carbonylation (PC, an index for protein oxidation), and glutathione (GSH) levels (a key antioxidant). Plasma MDA, PC, and GSH levels and erythrocytic superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activities were studied to evaluate the changes of antioxidant status in CRF. In the CRF group, the contraction and the relaxation of aorta and corpus cavernosum samples decreased significantly compared with controls (P < 0.05-0.001). Melatonin treatment of the CRF group restored these responses. In the CRF group, there were significant increases in tissue MDA and PC levels in all tissues with marked reductions in GSH levels compared with controls (P < 0.05-0.001). In the plasma, while MDA and PC levels increased, GSH, SOD, CAT, and GSH-Px activities were reduced. Melatonin treatment reversed these effects as well. In this study, the increase in MDA and PC levels and the concomitant decrease in GSH levels of tissues and plasma and also SOD, CAT, GSH-Px activities of plasma demonstrate the role of oxidative mechanisms in CRF-induced tissue damage, and melatonin, via its free radical scavenging and antioxidant properties, ameliorates oxidative organ injury. CRF-induced dysfunction of the aorta and corpus cavernosum of rats was reversed by melatonin treatment. Thus, supplementing CRF patients with adjuvant therapy of melatonin may have some benefit.  相似文献   
23.
CASE: A 40-year-old female presented with primary amenorrhoea at 17 years of age. She was tall at 98th centile for height with eunuchoidal body habitus. Her breast development was Tanner stage 3, pubic and axillary hair Tanner stage 4 with normal external genitalia. Her bone age was 13.4 years at a chronological age of 17.8 years. Gonadotrophins were elevated indicating primary ovarian failure. A diagnostic laparotomy revealed hypoplastic, infantile uterus with bilateral streak gonads. Chromosomal analysis showed a balanced reciprocal translocation 46X, t(X; 2) (q22 p13). She became pregnant by in vitro fertilization with egg donation at the age of 36 years. At 13 weeks of gestation, she presented with intractable vomiting. She had raised corrected serum calcium and parathyroid hormone concentrations consistent with the diagnosis of primary hyperparathyroidism (PHPT). She underwent parathyroidectomy at 24 weeks of gestation with removal of a large left inferior parathyroid adenoma which normalized her serum calcium. Multipoint linkage from a genome-wide screen has identified a region of suggestive linkage on chromosome 2p13.3-14 in some cases of familial isolated hyperparathyroidism (FIHP). CONCLUSION: To our knowledge, this is the first case of primary amenorrhoea due to reciprocal translocation involving chromosome 2 and the X chromosome associated with PHPT. PHPT in this case is most likely to be as a result of chromosome 2 involvement where a locus for FIHP has been identified. Identification of the gene involved on chromosome 2p13.3-14 will be of considerable interest.  相似文献   
24.
25.
Non-dipper blood pressure (NDP) as an indicator of autonomic dysfunction could be associated with hypertensive response to exercise (HRE) in diabetic patients. HRE was determined as a predictor of development of unborn hypertension. We aimed to investigate if any correlation among NDP and HRE in normotensive type 2 diabetic patients. A total of 59 consecutive type 2 diabetic patients without history of hypertension and with normal blood pressure (BP) on ambulatory blood pressure monitoring (ABPM) were enrolled to the study. We divided the study population in to two groups depending on their BP on ABPM as dipper (group 1) or non-dipper (group 2). There were 22 patients (mean age 49.5?±?7 and 10 male) in group 1 and 37 patients (mean age 53.1?±?10 and 14 male) in group 2. Daytime diastolic and mean BP of dippers and night time systolic and mean BP of non-dippers were significantly higher. HRE was not significantly different between groups (59% vs. 62%, p?=?0.820). Hemodynamic parameters during the exercise test were similar. At multivariate linear regression analysis, resting office systolic blood pressure (SBP) (r?=?0.611, p?r?=?0.266, p?=?0.002) and age (r?=?0.321, p?=?0.010) were independently correlated with peak exercises SBP. Logistic regression analyses identified the resting office SBP (OR 1.191, 95% CI 1.080–1.313; p?p?=?0.012) were independent predictors of HRE. This study revealed that HRE is not related with non-dipper BP in diabetic patients. This study could inspire to further studies to explore the main reasons of HRE in diabetes mellitus.  相似文献   
26.
The objective was to investigate the predictive factors for avascular necrosis (AVN) of bone in patients with systemic lupus erythematosus (SLE). The records of 868 patients with SLE from four centers were reviewed retrospectively. Forty-nine patients with AVN were identified. A total of 154 patients with SLE who did not have clinically apparent AVN during the follow-up were evaluated as a control group. The demographic, clinical, laboratory and management characteristics of these two groups of patients were recorded according to predefined protocol and compared. The prevalence of AVN was detected 6% in our SLE population. The highest dose corticosteroid administered within 4?months and total cumulative prednisolone dose were significantly higher in the SLE patients with AVN. The use of cytotoxic agent significantly higher proportion of patients with AVN. AVN tends to develop more frequently in male gender and younger patients. Oral ulcer, pleuritis, Raynaud??s phenomenon, cutaneous vasculitis, lymphadenopathy, autoimmune thyroiditis, peripheral neuropathy and Sj?gren??s syndrome were higher incidence in SLE patients with AVN. The bilateral femoral heads were the commonest site of involvement of AVN in our patients with SLE.  相似文献   
27.
Primary malignant melanoma arising in the oesophagus is a rare condition with a dismal prognosis. The diagnosis is often made following surgical resection even though the endoscopic features may be pathognomonic. The classical treatment is oesophagectomy even though the advanced disease stage at the time of presentation and aggressive biological behaviour of the tumour usually results in a fatal outcome. We report the case of a male patient initially diagnosed with squamous oesophageal carcinoma and treated with conventional neo-adjuvant chemo-radiotherapy. Poor clinical and radiological response resulted in a review of the original histology confirming a diagnosis of primary malignant melanoma of the oesophagus. The subsequent alteration in management conferred the patient an improved quality of life. A short review of the literature on primary malignant melanoma of the oesophagus supplements this case report.  相似文献   
28.
Background and Aim: Nocturnal gastro‐esophageal reflux causes heartburn and sleep disturbances impairing quality of life. Lifestyle modifications, like bed head elevation during sleep, are thought to alleviate the symptoms of gastroesophageal reflux. We tested the hypothesis that bed head elevation might decrease recumbent acid exposure compared to sleeping in a flat bed. Methods: Patients of symptomatic nocturnal reflux and documented recumbent (supine) reflux verified by esophageal pH test entered the trial. On day 1, baseline pH was measured while the patient slept on a flat bed. Then patients slept on a bed with the head end elevated by a 20‐cm block for the next 6 consecutive days from day 2 to day 7. The pH test was repeated on day 2 and day 7. Each patient acted as his own control. Results: Twenty of 24 (83.3%) patients with mean age of 36 ± 5.5 years completed the trial. The mean (± SD) supine reflux time %, acid clearance time, number of refluxes 5 min longer and symptom score on day 1 and day 7 were 15.0 ± 8.4 and 13.7 ± 7.2; P = 0.001, 3.8 ± 2.0 and 3.0 ± 1.6; P = 0.001, 3.3 ± 2.2 and 1.0 ± 1.2; P = 0.001, and 2.3 ± 0.6 and 1.5 ± 0.6; P = 0.04, respectively. The sleep disturbances improved in 13 (65%) patients. Conclusions: Bed head elevation reduced esophageal acid exposure and acid clearance time in nocturnal (supine) refluxers and led to some relief from heartburn and sleep disturbance.  相似文献   
29.
Long-term anticoagulation in patients with metallic prosthetic valve disease is required according to current guidelines. We describe a patient with a functioning mitral mechanical valve without anticoagulation for 27 years. A 46-year-old man admitted to the emergency department with complains of palpitation. The patient had a mitral valve replacement because of severe mitral stenosis. He discontinued warfarin treatment 1 month after surgery because of the unavailability of this drug in Turkey. Transthoracic echocardiography revealed functioning metalic mitral valve with a mean gradient of 9 mm Hg. Fluoroscopy showed normal excursions of the mechanical mitral valve. Transesophageal echocardiography was performed and revealed fresh thrombus formation in the left atrial appendix. Admission international normalized ration (INR) level was 1.79. Due to the higher INR level and long-term survival, genetic analysis of warfarin polymorphism was performed. There was a homozygous mutation in the vitamin K epoxide reductase complex 1 (VKORC1) 1173C>T and 1639G>A genotypes. The possible explanations of long-term survival and baseline higher INR level were linked to the mutation in warfarin metabolism. We also briefly review the literature.  相似文献   
30.
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