Cerebrovascular and metabolic perturbations in delayed heavy charged particle radiation injury

Focal heavy charged particle irradiation of the rabbit brain created defined lesions which were observable by nuclear magnetic resonance (NMR) and positron emission tomography (PET) imaging techniques. The lesions appeared approximately 9-11 months after left partial hemibrain irradiation with 30 Gy (230 MeV/u helium ions), and were restricted to the white matter tracts and deep perithalamic and thalamic regions. 82Rubidium PET and Gadolinium DTPA enhanced NMR imaging were used to detect blood-brain barrier perturbations. 18Fluordeoxyglucose PET studies demonstrated widespread decreases in cerebral glucose uptake in the cortex and thalamus of the irradiated hemisphere. NMR and PET imaging results correlated well with histological findings. Rabbits irradiated with 15 Gy did not demonstrate any abnormalities in the brain with sequential NMR scans through 14 months post-irradiation.     

Preparation and characterization of intelligent core-shell nanoparticles based on poly(D,L-lactide)-g-poly(N-isopropyl acrylamide-co-methacrylic acid).

New thermo-responsive, pH-responsive, and biodegradable nanoparticles comprised of poly(D,L-lactide)-graft-poly(N-isopropyl acrylamide-co-methacrylic acid) (PLA-g-P(NIPAm-co-MAA)) were developed by grafting biodegradable poly(D,L-lactide) onto N-isopropyl acrylamide and methacrylic acid. A core-shell type nano-structure was formed with a hydrophilic outer shell and a hydrophobic inner core, which exhibited a phase transition temperature above 37 degrees C suitable for biomedical application. Upon heating above the phase transition temperature, PLA-g-P(NIPAm-co-MAA) nanoparticle showed a polarity increase of pyrene in either buffer solution or intra-hepato-carcinoma cells as determined by fluorescence measurement, indicating that the structure of nanoparticles caused leakages from outer shell copolymers aggregation and collapsed. The drug loading level of 5-fluorouracil (5-FU) encapsulated in the PLA-g-P(NIPAm-co-MAA) nanoparticles can be as high as 20%. The release of 5-FU from nanoparticles was strongly controlled by the pH in the aqueous solution. Based on these results, PLA-g-P(NIPAm-co-MAA) nanoparticles can be used as a drug carrier for intracellular delivery of anti-cancer drug.     

Rhinitis Symptom Utility Index (RSUI) in Chinese Subjects: A Multiattribute Patient-preference Approach

Background: The Rhinitis Symptom Utility Index (RSUI), originally developed in the United States, consists of a patient-preference weighting scheme and a 10-item questionnaire measuring the severity and frequency of rhinitis related symptoms over a 14-day period. This study aimed to determine whether the Chinese RSUI could adopt the US-based multi-attribute utility function (MAUF) in scoring rhinitis symptoms. Methods: In a Hong Kong study, 116 Chinese adults with allergic rhinitis completed the RSUI questionnaire and 36-item Short-Form Health Survey (SF-36) after they had been seen by two otorhinolaryngologists for disease-severity ratings. Respondents then completed computer-administered direct preference measures, i.e., visual analogue scale (VAS) and standard gamble (SG) assessments. The VAS and SG data were used to estimate a MAUF for the Chinese-based RSUI. Results: The derived MAUF was somewhat different than the one developed for the US RSUI. Test–retest reliability for the Chinese RSUI was satisfactory (ICC = 0.71, p<0.001). Scores differentiated among cases with mild, moderate, and severe symptoms (p<0.001); and between those who did and did not require medications to control symptoms (p = 0.031). Findings were significantly correlated with SF-36 domain scores (r = 0.19 to 0.37; p=0.041 to <0.001). When the US-based scoring function was applied to the Chinese subjects, the resulting mean RSUI score was significantly lower (p<0.001). Comparisons between directly measured VAS and SG scores between the US and Chinese samples, demonstrated significant differences (all p<0.05), with the US subjects consistently rating rhinitis symptoms as worse than Chinese subjects. Conclusions: The Chinese RSUI has good measurement properties that reflect patient preferences from the Chinese. Results suggest that there are differences in preference rating between US and Chinese subjects and that use of the US-based preference function for the RSUI would bias the measurement of rhinitis symptom outcomes in Chinese subjects.     

Acromioclavicular joint dislocation: a comparative biomechanical study of the palmaris-longus tendon graft reconstruction with other augmentative methods in cadaveric models

Background  

Acromioclavicular injuries are common in sports medicine. Surgical intervention is generally advocated for chronic instability of Rockwood grade III and more severe injuries. Various methods of coracoclavicular ligament reconstruction and augmentation have been described. The objective of this study is to compare the biomechanical properties of a novel palmaris-longus tendon reconstruction with those of the native AC+CC ligaments, the modified Weaver-Dunn reconstruction, the ACJ capsuloligamentous complex repair, screw and clavicle hook plate augmentation.     

Early outcomes of surgery for small bowel obstruction: analysis of risk factors

OBJECTIVES: The study aimed to review the etiologies of patients who underwent surgery for small bowel obstruction (SBO) and to evaluate the risk factors affecting the early postoperative outcomes. MATERIALS AND METHODS: A case series of 430 patients (252 men) with a mean age of 64.5 years, who underwent 437 operations for SBO, were retrospectively reviewed. RESULTS: Peritoneal adhesions and hernia were the most common causes of SBO, contributing 42.3 and 26.8% of all cases, respectively. Strangulation occurred in 27.7% and caused nonviable bowel in 13.0% of obstructing episodes. Old age (age >/= 70 years), female patient, nonadhesive obstruction, and hernia were the independent significant factors associated with bowel strangulation. The 30-day mortality was 6.5%, and the median postoperative hospital stay was 8 days. Old age, the presence of premorbid pulmonary disease, and malignant obstruction were the independent factors associated with operative mortality. The overall complication rate was 35.5%, and old age was the only significant factor associated with postoperative complications. CONCLUSIONS: Surgery for SBO is still associated with significant mortality and morbidity. As old age is significantly associated with an increased incidence of strangulation, operative mortality, and complications, this group of patients should be managed with extra cautions to avoid unfavorable outcome of surgery.     

Prospective randomized trial of direct endomyocardial implantation of bone marrow cells for treatment of severe coronary artery diseases (PROTECT-CAD trial).

AIMS: Experimental studies have demonstrated that bone marrow (BM) cells can induce angiogenesis in ischaemic myocardium. Recently, several non-randomized pilot studies have also suggested that direct BM cells implantation appears to be feasible and safe in patients with severe coronary artery diseases (CAD). METHODS AND RESULTS: We performed a randomized, blinded, and placebo-controlled trial in 28 CAD patients. After BM harvesting, we assigned patients to receive low dose (1 x 10(6) cells/0.1 mL, n = 9), high dose (2 x 10(6) cells/0.1 mL, n = 10) autologous BM cells or control (0.1 mL autologous plasma/injection, n = 9) catheter-based direct endomyocardial injection as guided by electromechanical mapping. Our primary endpoint was the increase in exercise treadmill time and our secondary endpoints were changes in Canadian Cardiovascular Society (CCS) and New York Heart Association (NYHA) class, and myocardial perfusion and left ventricular ejection fraction (LVEF) assessed by single-photon emission computed tomography and magnetic resonance imaging, respectively. A total 422 injections (mean 14.6 +/- 0.7 per patient) were successfully performed at 41 targeted ischaemic regions without any acute complication. Baseline exercise treadmill time was 439 +/- 182 s in controls and 393 +/- 136 s in BM-treated patients, and changed after 6 months to 383 +/- 223s and 464 +/- 196 s [BM treatment effect +0.43 log seconds (+53%), 95% CI 0.11-0.74, P = 0.014]. Compared with placebo injection, BM implantation was associated with a significant increase in LVEF (BM treatment effect +5.4%, 95% CI 0.4-10.3, P = 0.044) and a lower NYHA class (odds ratio for treatment effect 0.12, 95% CI 0.02-0.73, P = 0.021) after 6 months, but CCS reduced similarly in both groups. We observed no acute or long-term complications, including ventricular arrhythmia, myocardial damage, or development of intramyocardial tumour or calcification associated with BM implantation. CONCLUSION: Direct endomyocardial implantation of autologous BM cells significantly improved exercise time, LVEF, and NYHA functional class in patients with severe CAD who failed conventional therapy.     

Results of irradiation in the squamous cell carcinomas of the anterior faucial pillar-retromolar trigone

Between January 1966 and August 1981, 159 patients with previously untreated squamous cell carcinomas of the anterior faucial pillar or retromolar trigone received definitive radiation therapy at The University of Texas M. D. Anderson Hospital and Tumor Institute. All except 11 patients were treated by external radiation including combination of electron beams with high-energy photons or 60Co to doses ranging from 60 Gy to 75 Gy. In the N0 patients, as a rule, only the ipsilateral subdigastric nodes were treated electively to a dose of 50 Gy. The 5-year determinate survival rate for the overall group was 83%. The cumulative recurrence rate showed that 92% of the patients had recurrence by 2 years. Therefore, all patients except those who died with no evidence of local disease less than 2 years after treatment were evaluated for local control. The failure rate for the evaluable patients was 29% for T1 lesions, 30% for T2 lesions, 24% for T3 lesions, and 40% for T4 lesions. After salvage surgery, which consisted of intraoral resection in one-third of the patients and of a composite operation in the other two-thirds, the ultimate failure rate was 0% for T1 lesions, 6% for T2 lesions, 8% for T3 lesions, and 20% for T4 lesions. Whereas stage was a poor indicator for treatment outcome, there was a significantly higher failure rate for infiltrative and/or ulcerated lesions (35%) than for exophytic or superficial lesions (15%). Histologic grade was of no prognostic significance, nor was there any significant difference in the failure rate for lesions originating on the anterior faucial pillar versus that for lesions on the retromolar trigone. Following radiotherapy, 30% of the patients developed some degree of bone exposure but only 5.6% (9 patients) required a segmental mandibular resection. The probability of bone exposure was not dose related and more likely reflected tumor location on the mucoperiosteum. Of the whole group, 16 patients (10%) experienced a neck failure with 8 ultimate failures after salvage surgery. Among the 16 patients who had neck failures, 13 were originally staged N0; 6 of these patients had failures that occurred in the electively treated ipsilateral subdigastric area, but the field was too small to cover the nodes adequately. Aspects of the radiotherapy techniques with combined electron and photon beams that may influence the treatment outcome are discussed.