Erratum to: Specific stressors in endonasal skull base surgery with and without navigation

European Archives of Oto-Rhino-Laryngology -     

Current therapeutical strategies for allergic rhinitis

Introduction: Allergic rhinitis is a common condition with increasing prevalence and is associated with several comorbid disorders such as bronchial asthma and atopic dermatitis. If allergen avoidance is not possible, allergen-specific immunotherapy is the only causal treatment option.

Areas covered: This review focuses on current treatments and the future outlook for allergic rhinitis. Pharmacotherapy includes mast cell stabilizers, antihistamines, glucocorticosteroids (GCSs), leukotriene receptor antagonists, and nasal decongestants. Nasal GCSs are currently regarded as the most effective treatment and are considered first-line therapy together with non-sedating antihistamines. The new formulation MP29-02 combines the nasal GCS fluticasone propionate with azelastine in one single spray and has achieved greater improvements than those under monotherapy with modern GCSs or antihistamines. Furthermore, this review discusses allergen immunotherapy alone and in combination with modern monoclonal antibodies.

Expert opinion: Despite the variety of medications for allergic rhinitis, ranging from general symptomatic agents like GCSs or decongestants, to more specific ones like histamine receptor or leukotriene blockers, to causal therapy like immunotherapy, many patients still experience treatment failures or unsatisfactory results. The ultimate goal may be to endotype every downstream pathway separately in order to offer patients individualized, targeted therapy with specific antibodies against the respective pathway.     

Erythropoietin production in healthy volunteers subjected to controlled hypobaric hypoxia: further evidence against a role for adenosine

Aims Objective of this study was to investigate whether adenosine modulates renal erythropoietin production.
Methods In the present study erythropoietin production was stimulated by hypobaric hypoxia by subjecting healthy volunteers to a simulated altitude of 4000  m in a low pressure chamber for 5.5  h. During exposure to hypoxia the subjects received i.v. in a randomized, single-blind, cross-over fashion the non-specific adenosine antagonist theophylline, the adenosine reuptake inhibitor dipyridamole and placebo.
Results Contrary to the working hypothesis, theophylline did not decrease and dipyridamole did not further boost erythropoietin concentrations.
Conclusions The results are in agreement with our earlier study using haemorrhage as a controlled physiological stimulus of erythropoietin production, and would question a major role for adenosine as a mediator of renal erythropoietin production.     

The Resource-Based Relative Value Scale. Toward the development of an alternative physician payment system

This article describes the design and methods of a study currently under way to develop a Resource-Based Relative Value Scale (RBRVS); an alternative basis for establishing the payment rate for the services and procedures (S/Ps) of physicians in medical and surgical specialties. Physician resource inputs to be measured include (1) S/P time, (2) pre-S/P and post-S/P times, (3) intensity, (4) practice costs, including malpractice premiums, and (5) the cost of specialty training. These five factors will be combined to produce an RBRVS denominated in nonmonetary units. In the initial phase of the study, data on time and intensity will be obtained through a national survey of physicians who perform these S/Ps. In the second, consensus phase of the project, the investigators will convene a panel of representatives of the medical profession, third-party payers, consumers, and other interested parties to examine areas of agreement and disagreement as to how an RBRVS should be used for policy purposes. The final results of this study are expected by the summer of 1988.     

Relative effects of diarrhea, fever, and dietary energy intake on weight gain in rural Bangladeshi children

Quantitative studies of morbidity, food intake, and somatic growth were done prospectively during 14 mo for 70 children aged 5-18 mo in two Bangladeshi villages. When random-effect regression models were used, monthly changes in weight were inversely related to proportions of days in the month with fever and diarrhea and positively related to energy intake per kilogram body weight. Interestingly, weight changes did not vary with age in this interval. Estimates indicate that increasing energy intakes to the recommended World Health Organization level would have a significantly greater effect on weight gain than would the elimination of diarrhea and fever. With energy at recommended intake and diarrhea and fever prevalence as found in US children, weight gain is predicted to be near that of the international reference population. Therefore, interventions aimed at improving dietary intake may be as important as infection-control programs for improving growth of children in poor developing nations.     

Effect of different levels of oral pyridoxine supplementation on plasma pyridoxal-5'-phosphate and pyridoxal levels and urinary vitamin B-6 excretion

Plasma pyridoxal-5'-phosphate and pyridoxal levels increased significantly (p less than 0.05) when single, oral bolus doses of pyridoxine were increased from 10 to 25 and from 25 to 50 mg in nine female volunteers. However, when the dose was increased to 100 mg, plasma pyridoxal-5'-phosphate levels did not differ significantly from those recorded after the 50 mg dose. Within 3 h plasma pyridoxal levels rose with a factor of 3.85 compared with the 50 mg dose but high pyridoxal levels were eliminated from the circulation. Renal clearance of pyridoxal remained a constant, low percentage (less than 2.0%) of each pyridoxine supplement in spite of the observed very high circulating pyridoxal levels. Pyridoxine supplementation is discussed in relation to circulating pyridoxal-5'-phosphate and pyridoxal availability for cellular metabolism.     

Emergency orthodontic treatment after the traumatic intrusive luxation of maxillary incisors.

Treatment of traumatically intruded teeth is based largely on empirical clinical experience rather than on scientific data. The aim of this qualitative meta-analysis was to provide an evidence base to evaluate the orthodontic repositioning approach. In a MEDLINE search of the literature in English, 14 reported patients involving 22 teeth were found to have been treated by this modality. Additionally, 3 new patients, involving 9 intruded teeth and presented herein, were combined to form a total study sample of 17 subjects (7 girls, 10 boys, aged 8.9 +/- 1.2 years). Orthodontic extrusive forces were applied in the immediate posttrauma period (up to 3 months), with a variety of orthodontic appliances. Repositioning was achieved for 90.3% of the affected teeth but failed in 9.7% because of inflammatory resorption (2 teeth) or a misdiagnosis of root fracture (1 tooth). Early complications included loss of pulp vitality and external root resorption. All intruded teeth with closed root apices lost their vitality regardless of the degree of intrusion, whereas among those with incomplete apices, 45.5% that had been moderately intruded remained vital. External resorption was encountered in 54.8% of the teeth. Loss of marginal bone support was rarely encountered. Late complications included inflammatory root resorption in teeth with closed apices, in which endodontic treatment was not initially performed, and obliteration of the pulp tissue in teeth that remained vital. The results show that this method is superior to other treatment alternatives.     

Cytofluorometric analysis of thymic interdigitating cells from C57BL/6 mice prior and after leukemogenic X-irradiation

The thymus is populated by various Ia+ cell populations, including epithelial cells, macrophages and dendritic cells. Thymic cell suspensions were stained with an anti-Ia antibody and shown by cytofluorometry to contain a small number of strongly Ia+ cells characterized by a large diameter. The cell population was separated with the aid of the fluorescence-activated cell sorter (FACS) and characterized. They were shown to express high levels of membranal Ia antigens; they demonstrated ATPase activity and displayed the ultrastructural features characteristic of the previously described thymic interdigitating cells. C57BL/6 mice were submitted to various regimens of X-irradiation. Whereas exposure to a single dose of X-irradiation was followed by an increase in the percentage of strongly Ia+ cells, exposure to a leukemogenic regimen of fractionated X-irradiation led to a decrease in the percentage and absolute numbers of these cells in the thymus. Of the C57BL/6 mice that were irradiated with fractionated X-irradiation, 77% developed leukemia. Intravenous injection of syngeneic bone marrow one day following the last irradiation or protection of the femur during irradiation prevented both the appearance of leukemia and the disappearance of interdigitating cells. Therefore an inverse correlation between the presence of thymic dendritic cells and the incidence of leukemia in C57BL/6 mice could be demonstrated. These findings are discussed in relation to the putative role of dendritic cells in the thymus.