Analysis of bronchial reactivity in epidemiological studies.

The measurement of bronchial reactivity in epidemiological studies has the advantage of quantifying an objective physiological feature of asthma. Bronchial reactivity was developed in a clinical setting and has been conventionally expressed as the dose of agonist producing a 20% fall in FEV1 (PD20). As PD20 can be estimated for less than 20% of subjects in general community surveys with the doses of agonist that are usually given, data from most subjects must be censored. Thus PD20 alone is a poor index of bronchial reactivity for epidemiological studies. Data from 809 aluminium smelter workers were used to evaluate alternative methods of analysing bronchial reactivity. Dose-response relationships were analysed by four methods: (1) PD20 by the conventional method of interpolating the dose on a logarithmic scale between the last two measurements of FEV1; (2) PD20 (with allowance for extrapolation), estimated by fitting an exponential curve to the dose-response data; (3) the linear regression slope between dose and FEV1 when significant; (4) the dose-response slope obtained in all subjects as the % change in FEV1 from baseline in response to total dose. When each of these measures was related to symptoms, diagnosis, and treatment of asthma, all differentiated between "asthmatic" and "non-asthmatic" subjects. The dose-response slope (method 4) had the advantages of simplicity and no censored data, and was shown to be clinically relevant. It is suggested that the dose-response slope should be used for the analysis of bronchial reactivity in epidemiological studies.     

Comparison of histamine and methacholine for use in bronchial challenge tests in community studies.

Measurement of bronchial reactivity is widely used in epidemiological surveys. Histamine has been compared with methacholine inhalation challenge in two samples of adults from a small town to determine which is the better agent for use in community studies. Increasing doses of histamine and methacholine were given, up to a maximum of 4 and 12 mumol respectively, according to the method of Yan et al, the provocative dose of agonist causing a 20% fall in FEV1 (PD20) being measured. More subjects had a measurable PD20 with methacholine than with histamine, both in a random sample of 108 subjects (25 v 11 subjects, p less than 0.01) and in an additional 95 subjects selected because of wheeze in the last 12 months (67 v 48 subjects, p less than 0.01). Side effects were mild with both agents but histamine caused voice change in more subjects (21% v 11%). Repeatability was assessed in a further group of subjects with wheeze in the last year. The 95% range for a single estimation of PD20 in subjects with a measured PD20 on at least one occasion was +/- 2.5 doubling doses for histamine (n = 25) and +/- 2.1 doubling doses for methacholine (n = 33). Thus methacholine has advantages over histamine for community studies of bronchial reactivity as it is possible to use doses that produce more PD20 measurements with fewer side effects.     

Reproducibility of DXA estimations of body fat in HIV lipodystrophy: implications for clinical research.

Dual-energy X-ray absorptiometry (DXA) estimates of body fat are increasingly used for the evaluation of human immunodeficiency virus lipodystrophy (HIV LD); however, limited data are available on their reproducibility. This information is essential for using this tool as an end point in treatment trials or as a diagnostic tool. This study evaluates the reproducibility of DXA body fat estimation in HIV-positive subjects with and without lipodystrophy. Thirty subjects representing a spectrum of severity of fat redistribution underwent same-day repeat whole-body DXA scans (Hologic QDR 4500A scanner). Root mean square coefficients of variation (RMS-CV) were used to estimate minimum detectable differences (MDDs) for body fat content in different regions. Absolute MDD was calculated by multiplying the MDD by the mean fat-mass value for each anatomical area. The RMS-CV ranged from 4.0% for arm fat to 1.6% for total fat. Relative and absolute MDD values ranged from 11.0% or 160 g for arm fat to 4.3% or 628 g for total fat. DXA measurements of regional body fat mass in subjects with HIV show similar reproducibility to other populations. Minimal detectable differences were smaller than differences observed in published studies for all measurements. DXA is a sensitive tool for detecting changes in peripheral fat among patients with HIV lipodystrophy.     

Secretory meningiomas: systematic analysis of epidemiological,clinical, and radiological features

Background  

Secretory meningiomas are known as a rare histological subtype within the meningioma family. In contrast to benign intracranial meningiomas, they are dreaded for causing an extensive perifocal cerebral tumor edema and life-threatening complications. The objective of the present study is a systematic, retrospective analysis of epidemiological, clinical, and radiological features of secretory meningiomas to predict potential patterns prior to surgery to reduce associated morbidity.     

Single semen analysis as a predictor of semen quality： clinical and epidemiological implications

It is generally thought that a single ejaculate is a bad predictor of semen quality of a subject, because of significant intra-individual variation. Therefore, we investigated the degree to which the results of a first semen analysis differ from that of a second analysis among men from a how the two different semen results mirrored the overall general population in Norway. In addition, we analysed semen quality assessment. A total of 199 volunteers participated in the study and delivered two semen samples with an interval of 6 months. The semen parameters were determined according to the World Health Organization （WHO） 1999 guidelines, which were also used to determine whether semen quality was normal or abnormal. In addition, the DNA fragmentation index （DFI） was determined using the Sperm Chromatin Structure Assay. The two samples from each individual were very similar with regard to standard semen parameters and DFI （rs： 0.67-0.72）, and there were no significant systematic differences between the two samples. The result of the first sample （normal/abnormal） was highly predictive of the overall conclusion based on the two samples （sperm concentration： in 93% of the cases （95% confidence interval [CI]： 89%-96%）; sperm motility： in 85% of the cases （95% CI： 79%-89%）; overall semen quality： in 85% of the cases （95% CI： 80%-90%）. In epidemiological studies, one ejaculate is a sufficient indicator of semen quality in a group of subjects. In a clinical situation, when the question is whether the semen quality is normal or not, the first ejaculate will, in at least 85% of cases, give a correct overall conclusion.     

Esophageal schwannoma: Case report and epidemiological,clinical, surgical and immunopathological analysis

IntroductionSchwannoma is a tumor of the peripheral nervous system originated in the Schwann cells of the neural sheath.Presentation of caseA 43-years-old male complained of odynophagia, dysphagia and hemoptysis. The upper gastrointestinal endoscopy showed a smooth elevated lesion, 20 cm from the incisor teeth, occupying the entire lumen of the esophagus. The chest computed tomography (CT) scan showed a lesion of 7 cm and superior mediastinal, lower paraesophageal and cardiac enlarged lymph nodes. A posterolateral thoracotomy was performed with total esophagectomy without intraoperative complications. The anatomopathological analysis revealed fusocellular mesenchymal neoplasia of low malignancy potential. The immunohistochemical study showed positivity for S-100 protein and KI67 antibodies and absence of staining for CD117, CD34, ALK protein, SMA and Desmin. Thus, the morphological and immunohistochemical findings pointed to the diagnosis of esophageal Schwannoma.DiscussionAlthough rare and indolent, Schwannoma occurs in the peripheral nervous system, being uncommon in the esophagus.ConclusionThe immunohistochemical study is essential for the diagnosis, which is based on the positivity for S-100 protein and absence of staining for CD34 and CD117.     

Pressure ulcers in cardiac surgery: Few clinical studies,difficult risk assessment,and profound clinical implications

Pressure ulcers (PUs) are a common complication after cardiac surgery, with almost one third of patients suffering from PUs during hospitalisation. Because of the burden that PUs exert on both the patients and the health care system, prevention is of utmost importance. The first step in successful prevention, however, includes the identification of the main features that render patients prone to PU development. Cardiac surgery population is not adequately addressed in current clinical trials and studies. Few studies focused specifically on cardiac surgery patients, but the majority included cardiac surgery patients within a heterogeneous population of acute or critical care patients. Therefore, additional research is warranted to understand the unique risk profile of patients undergoing cardiac surgery. Intraoperative risk factors that affect tissue tolerance have not been thoroughly investigated but are likely to play an important role, which might explain the epidemiology of a PU. Further research is also needed to better comprehend the risk of PUs among cardiac surgery patients and to design effective and tailored preventative measures with the help of newer tools for risk assessment.     

Histopathological analysis of intracerebral hemorrhage: implications for clinical management

Background  

The clinical impact of routine neuropathologic examination of samples from patients with intracerebral hemorrhage (ICH) is unclear.     

Biliary carcinoembryonic antigen, non-specific cross-reacting antigen and biliary glycoprotein--their analysis and clinical aspects

Bile sample were collected in 17 cases of choledocholithiasis, 28 of malignant obstructive jaundice and 7 of hepatolithiasis and biliary CEA levels were measured by the EIA method. In the malignant obstructive jaundice group, the biliary CEA level was higher than that in the choledocholithiasis group and the bile gave a positive test for CEA more frequently than the serum. As for the hepatolithiasis group, the biliary CEA level was higher than that in the malignant obstructive jaundice group. The EIA method, however, had a possibility that not only CEA but also CEA-related antigens were measured. Therefore, antigen for CEA, NCA and BGP were prepared, and biliary CEA, NCA and BGP levels were measured by the ELISA method. The biliary CEA level (mean +/- S.D.) was 0.086 +/- 0.26 for 21 cases of cholelithiasis, 0.119 +/- 0.24 for 15 of pancreatic carcinoma, and 0.117 +/- 0.016 for 17 cholangiocarcinoma, cholecystic carcinoma, being thus significantly (p less than 0.05) higher in malignant disease. In malignant disease, both biliary NCA and biliary BGP increased, though not so remarkable compared with CEA. Even in controls, the biliary NCA and BGP levels were not negligible.     

Vocal cords-carina distance in anaesthetised Caucasian adults and its clinical implications for tracheal intubation

Previous work has assessed vocal cords-carina distance in Chinese patients and compared it to commonly used tracheal tubes. In addition, an attempt was made to identify surface anatomy measurements with short tracheas. We have examined the length of tracheas in Caucasian patients and compared it with currently used tracheal tubes. We have investigated a wider range of surface anatomy measurements in an attempt to correlate measurements with vocal cords-carina distance and identifying patients who may be at risk of endobronchial intubation. In this study, the vocal cords-carina distance was measured in 150 anaesthetised Caucasian patients with a fibreoptic bronchoscope. We also attempted to correlate height and various surface anatomy measurements on the patients' chest, neck and limb regions to predict those patients at risk of endobronchial intubation. The mean vocal cords-carina distance was 12.7 cm (standard deviation 1.6 cm). The best predictors in our study of vocal cords-carina distance less than 11.3 cm were a height of < or = 182 cm, an ulnar length of < or = 31.2 cm or a thyroid to xiphisternum distance of < or = 31.8 cm. This correlation is poor however and prediction of vocal cords-carina distance remains difficult clinically. It was therefore concluded that surface anatomy measurements are a poor predictor of vocal cords-carina distance.     

原发性支气管肺淀粉样变性10例临床分析

目的探讨原发性支气管肺淀粉样变性临床表现、诊断、治疗及预后。方法回顾性分析10例原发性支气管肺淀粉样变性患者的临床特点。结果原发性支气管肺淀粉样变性患者临床表现为咳嗽、咳痰、咯血、气促,可经纤维支气管镜、肺穿刺或胸腔镜手术活检病理检查确诊,刚果红染色阳性为典型病理特征。结论本病临床少见,病理检查为确诊金标准。目前无疗效确切的治疗药物,气管受累及弥漫性病变者预后差。     

Correlates for nocturia: a review of epidemiological studies

Traditionally, nocturia was considered to be one of the symptoms of prostatism. However, this symptom has unusual characteristics compared with other lower urinary tract symptoms; for example, there is only a mild benefit for nocturia from treatment for benign prostatic hyperplasia. In the past decade, nocturia has been investigated as a separate symptom in epidemiological studies. These types of studies have shown various correlates for nocturia other than benign prostatic hyperplasia, as well as the prevalence of this symptom. These correlates include age, race/ethnicity, medical problems (such as hypertension, diabetes and stroke) psychological aspects, tasting habits, quality of life and even mortality. The cause-and-effect associations are not always obvious between nocturia and its correlates. In the present article, the author attempts to comprehensively review the correlates for nocturia shown by epidemiological studies.     

An epidemiological study of the prevalence and clinical aspects of oral mucosal lesions in adults

The frequency of the different lesions of oral mucosa detected in the patients presenting for outpatient dental care was 37.6%. Cheilitis, lesions in various areas of oral mucosa, and glossitis were prevalent. Generalized stomatitis accounted for only 3.7%. Except for few cases with stomatitis and glossitis, the clinical aspect of these lesions was benign, fact explaining why the patients have not been aware of and have not presented for dental care. As some of these lesions are believed to be precancerous states, thorough investigations are needed for understanding their etiology, relationship with odontic, periodontal and general disorders, and recurrent course.     

Chronic kidney disease in Cuba: epidemiological studies, integral medical care, and strategies for prevention

The experience of the Republic of Cuba regarding epidemiological studies, integral medical care, and strategies for the prevention of chronic kidney disease is summarized in this report. Cuba has a National Program for Chronic Renal Disease, Dialysis, and Renal Transplantation. There is a national nephrology net, integrated by the Institute of Nephrology as the coordinator center, that has 47 nephrology services with a hemodialysis unit (24 of them with peritoneal dialysis unit), 9 transplantation centers, 33 organ procurement hospitals, and 5 histocompatibility laboratories.In 2004, the incidence rate in dialysis patients was 111 pmp, and the prevalence rate was 149 pmp, demonstrating an increasing mean of 17.0% and 10.0% per year, respectively. Renal transplantation rate was 16.6 pmp. The detection, registration, and follow-up of patients with chronic kidney disease (serum creatinine > or =1.5 mg/dL or glomerular filtration rate <60 mL/min) by family doctors was 9,761 patients, 0.87 patients per 1,000 inhabitants.In the 1980s, three population-based screening studies were performed to define the burden of chronic renal failure in different regions of Cuba. The prevalence rate was 1.1, 3.3, and 3.5 per 1,000 inhabitants, respectively. At present, another three population-based screening studies are ongoing in order to detect the chronic kidney disease in earliest stages.The continuing medical education activities have been very useful in raising the awareness of medical doctors and the basic health staff about the threats posed by and the strategies to prevent, diagnose, and treat chronic kidney disease.     

Fibrodysplasia ossificans progressiva in Spain: epidemiological, clinical, and genetic aspects

We aimed to investigate the epidemiological determinants, clinical features, and genetic pattern of FOP in our country by evaluating the entire population of patients identified according to a combination of methods. To achieve this, 24 individuals were confirmed as FOP cases, 17 of whom were alive at the end of 2011 (point prevalence=0.36×10(-6)). The gender distribution (male/female ratio=13/11) and the concurrent range of ages (from 4 to 53years; mean±SD: 30.2±13.8) are in agreement with similar reports. Twenty-one (87.5%) had characteristic congenital malformations of the big toe, and short thumbs were found in 65.2% of cases. In addition, other skeletal malformations such us fusion of the posterior elements of the cervical spine (89.0%), knee osteochondromas (71%), scoliosis (54.5%), and short and broad femoral neck (52.6%) were observed. All had developed mature ossicles of heterotopic bone in typical anatomic and temporal patterns, ranging in number from 1 to 17 (9.5±3.9). Age at appearance of first ossifying lesion varied from 3months to 15years. Mean age at diagnosis was 7.3±5.1years and the average delay in reaching the correct diagnosis after the onset of heterotopic ossification was 2.7years (range=0-12years). Biopsy of the pre-osseous lesions was performed in 11 of 20 (55.0%), providing no useful information for the diagnosis of FOP. Seven of 18 (38.9%) reported some hearing loss, and 5 (27.8%) experienced diffuse thinning of the hair or were bald. No patient had relatives with a typical FOP clinical picture. Fourteen of the 16 cases which were genetically investigated displayed the single heterozygous mutation c.617G>A in exon 4 of the ACVR1 gene. One of the two patients who did not present with the canonical ACVR1 mutation showed a heterozygous mutation c.774G>C in exon 5 leading to the substitution of Arginine 258 with a serine. The other patient had a heterozygous c.774G>T substitution in exon 5 leading to the same amino acid change (p.Arg258Ser). These two patients had only nonspecific abnormalities of the great toe, lacked the typical anatomic and developmental pattern of heterotopic ossification, and shared a trend toward uncommon clinical features. These results provide new insight on the epidemiological and clinical traits of FOP, reinforcing the notion of its worldwide homogeneity. The molecular characterization of ACVR1 sequence variation will contribute to the understanding of the genetic profile of this devastating disease in different geographical areas.