Clinical and basic science research on allergic rhinitis and asthma from Nassau University Medical Center.

Allergic inflammatory disorders involved with the upper and lower airway are related to allergic rhinitis and asthma. The role of nasal provocation and airway epithelium as models to evaluate allergic rhinitis and asthma are illustrated in studies from our research center. New concepts related to the anti-inflammatory effect of nasal steroids, antihistamines, isomers of beta 2 agonists, cromolyn sodium, and enoxaparin sodium related to airway remodeling are addressed in this article.     

Clinical conference in pulmonary disease. Factors influencing upper airway closure

The factors which produce closure of the upper airway (UAW) in patients with the sleep apnea syndrome are still poorly understood. A distinction should be made between the factors which induce closure and those which reopen the UAW. Neurologic factors include arousal phenomena, the magnitude and timing of various motor outputs, and postsynaptic inhibition. Mechanical factors include the anatomy of the UAW, especially that above the tongue, the position of the neck and jaw, and mucosal adherence once occlusion has occurred. Muscle factors include the type of myosin isozyme, the forces generated by the large number of UAW muscles and the diaphragm, and the possibility of high-frequency fatigue occurring during occlusion. Hypoxia and acidosis probably play a critical role in making the UAW less stable. Currently, the best method to prevent UAW closure is by nasal CPAP. Patients with life-threatening arrhythmias due to sleep apnea should have a tracheostomy. The role of drugs is controversial. Respiratory or muscle stimulants should probably be avoided; oxygen, medroxyprogesterone, and protriptyline may be useful adjuncts.     

国家感染性疾病临床医学研究中心2021年度学术年会会议纪要

1 新冠疫情防控、疫苗研发进展 石正丽介绍了SARS相关冠状病毒(SARS related coronavirus, SARSr-CoV)遗传进化和跨种感染的最新研究进展.自然界野生动物(如蝙蝠和穿山甲)携带的SARSr-CoV存在丰富的遗传多样性,基因组序列分析显示这些病毒的基因组主要差异在囊膜蛋白S和附属蛋白.根据...     

Bronchiectasis, exacerbation indices, and inflammation in chronic obstructive pulmonary disease

Relationships between high-resolution computed tomography (HRCT) findings in chronic obstructive pulmonary disease (COPD) and bacterial colonization, airway inflammation, or exacerbation indices are unknown. Fifty-four patients with COPD (mean [SD]: age, 69 [7] years; FEV(1), 0.96 [0.33] L; FEV(1) [percent predicted], 38.1 [13.9]%; FEV(1)/forced vital capacity [percent predicted], 40.9 [11.8]%; arterial partial pressure of oxygen, 8.77 [1.11] kPa; history of smoking, 50.5 [33.5] smoking pack-years) underwent HRCT scans of the chest to quantify the presence and extent of bronchiectasis or emphysema. Exacerbation indices were determined from diary cards over 2 years. Quantitative sputum bacteriology and cytokine measurements were performed. Twenty-seven of 54 patients (50%) had bronchiectasis on HRCT, most frequently in the lower lobes (18 of 54, 33.3%). Patients with bronchiectasis had higher levels of airway inflammatory cytokines (p = 0.001). Lower lobe bronchiectasis was associated with lower airway bacterial colonization (p = 0.004), higher sputum interleukin-8 levels (p = 0.001), and longer symptom recovery time at exacerbation (p = 0.001). No relationship was seen between exacerbation frequency and HRCT changes. Evidence of moderate lower lobe bronchiectasis on HRCT is common in COPD and is associated with more severe COPD exacerbations, lower airway bacterial colonization, and increased sputum inflammatory markers.     

Energy expenditure and rib cage-abdominal motion in chronic obstructive pulmonary disease

The resting energy expenditure (REE) was measured by indirect calorimetry in 10 patients with chronic obstructive pulmonary disease (COPD) in stable clinical state and in 10 normal subjects. In order to avoid artefactually increased values, REE was obtained from prolonged measurements in steady state using a ventilated hood, without facial apparatus. The REE of COPD patients was significantly increased to 117% of predicted basal metabolic rate and to 125% of the control group values. Rib cage and abdominal movements were measured in COPD patients by inductance plethysmography and expressed with three indices: rib cage contribution to tidal volume (RC/VT), variability in compartmental contribution to tidal volume (SD RC/VT), and maximal compartmental amplitude/tidal volume ratio (MCA/VT). No correlation was found between REE and any of the indices of rib cage and abdominal motion. We conclude that the REE is increased in patients with COPD in stable clinical state, but is not related to the degree of abnormal rib cage-abdominal motion.     

Cases from the Osler Medical Service at Johns Hopkins University. Antiglomerular basement membrane disease

A 47-year-old Taiwanese man with no notable medical history was admitted with low-grade fevers and night sweats that had persisted for 5 to 6 weeks. An extensive investigation at another hospital could not determine the cause of the fevers, but documented acute renal failure with a blood urea nitrogen level of 60 mg/dL and a serum creatinine level of 5.6 mg/dL. He was admitted to the Johns Hopkins Hospital for further evaluation.The patient, who had been living in the United States for the past 20 years, reported no recent travel and no behaviors that are associated with transmission of human immunodeficiency virus. He was not taking any medications, and he denied using herbal or nutritional supplements. He had no recent weight loss. There were no specific complaints on review of systems. On physical examination, he was a thin, middle-aged man in no distress. Vital signs included a temperature of 37.5 degrees C, a blood pressure of 166/86 mm Hg, a pulse of 70 beats per minute, a respiratory rate of 16 breaths per minute, and 99% oxygen saturation on room air. Sclera were anicteric, and he had no palpable adenopathy. His lungs were clear, and his heart rate was regular without extra sounds. His abdomen was thin, nontender, and without masses or organomegaly. There was no edema or signs of embolism in the extremities. Laboratory studies revealed a white blood cell count of 14,200/mL(3), a hematocrit of 23.1%, and a platelet count of 456,000/mL(3). Blood chemistries were notable for a blood urea nitrogen level of 61 mg/dL and a serum creatinine level of 7.6 mg/dL. Levels of aminotransferases, total bilirubin, and alkaline phosphatase were within normal limits. Urinalysis revealed large hemoglobin, 1+ protein, numerous red blood cells, and 3 to 5 white blood cells. Numerous red blood cell casts were seen on microscopic examination of the urine sediment. The patient's erythrocyte sedimentation rate was >130 mm/h, and his C-reactive protein level was elevated at 12.6 mg/dL. Serologies were negative for antinuclear antibodies and antineutrophil cytoplasmic antibodies; serum complement levels were normal. What is the diagnosis?     

Infectious complications among 620 consecutive heart transplant patients at Stanford University Medical Center.

A total of 1073 infectious episodes (IEs) that occurred in 620 consecutive heart transplantation patients at Stanford Medical Center between 16 December 1980 and 30 June 1996 were reviewed. Infectious complications were a major cause of morbidity and mortality, second only to rejection as the cause of early deaths and the most common cause of late deaths. Of the IEs, 468 (43.6%) were caused by bacteria, 447 (41.7%) by viruses, 109 (10.2%) by fungi, 43 (4.0%) by Pneumocystis carinii, and 6 (0.6%) by protozoa. The largest number of IEs occurred in the lungs (301 [28.1%]). A significant reduction in the incidence of IEs and a delay in presentation after transplantation were observed; these were most likely related to the introduction of new chemoprophylactic regimens during the study period and prevention of significant disease caused by cytomegalovirus.     

Career choices of 135 cardiology trainees at Duke University Medical Center from 1970 to 1984

Alarm has been expressed at recently presented evidence showing that diminishing numbers of physicians are entering academic careers. The experience of the cardiology training program at a university medical center between 1970 and 1984 was reviewed to determine the career paths chosen by its trainees. During the study period, 135 physicians received training. Between 1970 and 1978 the percentage of trainees making academic medicine their initial career choice fluctuated considerably. Beginning in 1978, the percentage entering academic medicine steadily increased; in the most recent class, 8 of 9 trainees accepted academic faculty positions. Among 72 former trainees who joined an academic faculty after finishing training, approximately 7% per year left academic medicine for clinical practice. The median length of an academic career was 10 years. Individual institutions may be able to reverse the national trend of trainees making clinical practice their initial career choice. However, physicians who leave academic medicine for clinical practice may continue to deplete faculty ranks.