Effect of acute tobacco smoke inhalation on the mechanical responses of isolated rat cardiac muscle

To evaluate the effects of acute inhalation of tobacco smoke upon the intrinsic properties of cardiac muscle, rats were exposed to cigarette smoke from 2R1 Kentucky reference cigarettes in special smoking chambers for periods of 10Min/hr for 5 hr. Animals were sacrificed, and the mechanical properties of isolated left ventricular papillary and columnar carneae preparations were studied. Mean COHb concentration of animals exposed to tobacco smoke was 13.2 ± 0.9 vol%. No significant difference was found in rats exposed to tobacco smoke when compared to shams in (1) cardiac chamber weight or chamber wet-to-dry weight ratios, (2) cardiac muscle performance in oxygenated Krebs-Henseleit solution (95% O₂, 5% CO₂), (3) muscle performance during 60 min of hypoxia (95% N₂, 5% CO₂) followed by 30 min of reoxygenation, (4) muscle performance during graded hypoxia with and without glycolytic blockade (iodoacetic acid 10^?4m), or (5) sensitivity of myocardial performance to isoproterenol. Thus, after acute exposure to tobacco smoke, no effects on the intrinsic mechanical properties of rat cardiac muscle were demonstrable.     

Mycobacterium terrae synovitis and osteomyelitis

An immunocompromised patient with Mycobacterium terrae synovitis and osteomyelitis is presented. Therapeutic recommendations are made based upon existing knowledge of the pathogenesis, course, and outcome of similar infections with nontuberculous mycobacteria.     

Combination of external-beam radiotherapy with intraoperative electron-beam therapy is effective in incompletely resected pediatric malignancies

PURPOSE: Intraoperative electron-beam radiotherapy (IOERT) has been applied for local dose escalation in over 1,400 patients in Heidelberg since 1991. Among these were 30 children, in 18 of whom IOERT was employed in radiation treatment with external-beam radiotherapy (EBRT) on account of incomplete resection. We address the question whether IOERT is able to compensate for microscopic or macroscopic tumor residue if employed in the overall radiation regimen. METHODS AND MATERIALS: The data of the aforementioned 18 children were analyzed with regard to local recurrence, overall survival, and complication rates. All children suffered from either sarcomas or neuroblastomas. In all children, IOERT was employed for local dose escalation after or before EBRT. RESULTS: After a median follow-up of 60.5 months, 15 of the treated children are alive. One local failure has been observed. Six children show clinically significant late morbidity, including the loss of a treated limb (Radiation Therapy Oncology Group Grade 4 [RTOG 4]), a severe nerve lesion (RTOG 3), an orthopedic complication (RTOG 2), a ureteral stenosis (not clinically significant), and a kidney hypotrophy (not clinically significant). In 1 child a fracture due to radionecrosis (RTOG 4) was diagnosed; however, in the follow-up, local tumor relapse was diagnosed as another possible reason for the fracture. CONCLUSIONS: Regarding the low incidence of local failure, IOERT seems to be able to compensate incomplete tumor resection in childhood sarcoma and neuroblastoma patients. The incidence of late morbidity is low enough to justify the employment of IOERT as part of the radiation treatment regimen for pediatric patients.     

Stereotactic linac-based radiosurgery in the treatment of cerebral arteriovenous malformations located deep, involving corpus callosum, motor cortex, or brainstem

PURPOSE: To evaluate patient outcome and obliteration rates after radiosurgery (RS) for cerebral arteriovenous malformations (AVM) located deep, in the motor cortex or brainstem and those involving corpus callosum. METHODS AND MATERIALS: This analysis is based on 65 patients. AVM classification according to Spetzler-Martin was 13 patients Grade 2, 39 Grade 3, 12 Grade 4, and 1 Grade 5. Median RS-based AVM score was 1.69. Median single dose was 18 Gy. Mean treatment volume was 5.2 cc (range, 0.2-26.5 cc). Forty patients (62%) experienced intracranial hemorrhage before RS. Median follow-up was 3.0 years. RESULTS: Actuarial complete obliteration rate (CO) was 50% and 65% after 3 and 5 years, respectively. CO was significantly higher in AVM <3 cm (p < 0.02) and after doses >18 Gy (p < 0.009). Annual bleeding risk after RS was 4.7%, 3.4%, and 2.7% after 1, 2, and 3 years, respectively. AVM >3 cm (p < 0.01), AVM volume >4 cc (p < 0.009), and AVM score >1.5 (p < 0.02) showed a significant higher bleeding risk. Neurologic dysfunction improved, completely dissolved, or remained stable in 94% of patients. CONCLUSIONS: Surgically inaccessible AVM can be successfully treated using RS with acceptable obliteration rates and low risk for late morbidity. The risk of intracranial hemorrhage is reduced after RS and depends on RS-based AVM score.     

Intraoperative electron boost radiation followed by moderate doses of external beam radiotherapy in limb-sparing treatment of patients with extremity soft-tissue sarcoma

PURPOSE: To analyze long-term prognosis and morbidity after limb-sparing treatment of patients with extremity soft-tissue sarcoma, with intraoperative electron boost radiotherapy (IOERT) followed by a moderate dose of external beam radiotherapy (EBRT). METHODS AND MATERIALS: A total of 153 patients who were treated in a single center from 1991 to 2004 were evaluated. Median IOERT dose was 15 Gy, mean EBRT dose 43 Gy (range, 40-50.4 Gy) in conventional fractionation (1.8-2 Gy). Median duration of follow-up was 33 months. Acute toxicity was assessed with Common Toxicity Criteria; late toxic effects were scored according to European Organization for Research and Treatment of Cancer/Radiation Therapy Oncology Group criteria. RESULTS: Five-year overall survival and 5-year local control rates were 77% and 78%, respectively. Whereas tumor size, patient age, and EBRT dose did not significantly affect outcome, resection status and grading were significant for survival; resection status and IOERT dose were significant for local control. Extremity salvage until death or time of follow-up was achieved in 90% of our patients, 86% of whom showed excellent limb function without impairment in activities of daily life. Acute toxicity Grade 2-4 was observed in 23% and late toxicity Grade 2-4 in 17% of patients. CONCLUSIONS: Treatment with IOERT combined with moderate doses of external beam irradiation yields high local control and extremity preservation rates in resected extremity soft-tissue sarcoma.     

Antisense strategies in degenerative joint diseases: sense or nonsense?

Oligodeoxynucleotides, ribozymes, and RNA interference make part of the antisense strategy, a new tool proposed to conquer cancer, viral infections, as well as cardiovascular and rheumatic diseases. The silencing effect of antisense strategies is both highly specific and potent - and only requires that the sequence of the target RNA is known. However, so far neither RNAi nor ribozymes have been approved for clinical use and only a single antisense agent is on the market. In the context of degenerative joint diseases, experimental data in the field of antisense strategies are still rare. Several studies from rheumatoid arthritis (RA), an inflammatory condition that leads to the progressive destruction of cartilage and bone within affected joints, however revealed promising results and taught us important lessons that might also be useful in therapeutic approaches for osteoarthritis (OA). To introduce these therapies in clinical practice, however, several hurdles still have to be overcome.     

Bacterial decontamination of surgical wounds treated with Lavasept

In a prospective randomized controlled double-blind study in 50 acutely injured patients, bacterially contaminated type 2–4 soft tissue wounds were treated with moist dressings of 0.2% Lavasept^® (fractionated polyhexamethylenbiguanide and macrogolum 4000) solution (n=28) in comparison with Ringer solution (n=22). Standardized swabs were taken on days 0, 2, 8 and 15 and investigated for microorganisms. For a quantitative evaluation, the number of colony forming units (CFU) was determined by a serial dilution technique. The tissue compatibility and anti-inflammatory effect were rated on a scale of 0 (=bad) to 3 (=very good). The most frequently found microorganism was Staphylococcus aureus, which was isolated from 13 wounds. Use of Lavasept^® led to a faster and significant reduction in microorganisms on the wound surfaces. The number of CFU per wound remained constant or decreased, in contrast to the wounds treated with Ringer solution. This was true for both Gram-positive and Gram-negative bacteria. There was no evidence of impaired wound healing in either group. The anti-inflammatory effect and the tissue compatibility of Lavasept^® were rated significantly better than that of Ringer solution. It is concluded that Lavasept^® combines antiseptic action with good tissue compatibility.     

Health expenditure growth: reassessing the threat of ageing

In this paper we evaluate the respective effects of demographic change, changes in morbidity and changes in practices on growth in health care expenditures. We use microdata, i.e. representative samples of 3441 and 5003 French individuals observed in 1992 and 2000. Our data provide detailed information about morbidity and allow us to observe three components of expenditures: ambulatory care, pharmaceutical and hospital expenditures.We propose an original microsimulation method to identify the components of the drift observed between 1992 and 2000 in the health expenditure age profile. On the one hand, we find empirical evidence of health improvement at a given age: changes in morbidity induce a downward drift of the profile. On the other hand, the drift due to changes in practices is upward and sizeable. Detailed analysis attributes most of this drift to technological innovation.After applying our results at the macroeconomic level, we find that the rise in health care expenditures due to ageing is relatively small. The impact of changes in practices is 3.8 times larger. Furthermore, changes in morbidity induce savings which more than offset the increase in spending due to population ageing.