Side effects of proton beam therapy of choroidal melanoma in dependence of the dose to the optic disc and the irradiated length of the optic nerve

Graefe's Archive for Clinical and Experimental Ophthalmology - To analyze the impact of the dose to the optic disc and the irradiated length of the optic nerve on radiation-induced optic...     

Genetic Background Modifies the Effects of Type 2 Cannabinoid Receptor Deficiency on Bone Mass and Bone Turnover

Cannabinoid receptors and their ligands play significant roles in regulating bone metabolism. Previous studies of type 1 cannabinoid receptor-deficient mice have shown that genetic background influences the skeletal phenotype. Here, we investigated the effects of genetic background on the skeletal phenotype of mice with type 2 cannabinoid receptor deficiency (Cnr2 ^?/?). We studied Cnr2 ^?/? mice on a CD1 background and compared the findings with those previously reported in Cnr2 ^?/? C57BL/6 mice. Young female Cnr2 ^?/? CD1 mice had low bone turnover and high trabecular bone mass compared with wild-type (WT), contrasting with the situation in Cnr2 ^?/? C57BL/6 mice where trabecular bone mass has been reported to be similar to WT. The Cnr2 ^?/? CD1 mice lost more trabecular bone at the tibia with age than WT due to reduced bone formation, and at 12 months there was no difference in trabecular bone volume between genotypes. This differs from the phenotype previously reported in C57BL/6 Cnr2 ^?/? mice, where bone turnover is increased and bone mass reduced with age. There were no substantial differences in skeletal phenotype between Cnr2 ^?/? and WT in male mice. Cortical bone phenotype was similar in Cnr2 ^?/? and WT mice of both genders. Deficiency of Cnr2 has site- and gender-specific effects on the skeleton, mainly affecting trabecular bone, which are influenced by genetic differences between mouse strains. Further evaluation of the pathways responsible might yield new insights into the mechanisms by which cannabinoid receptors regulate bone metabolism.     

Vertebral artery injuries in cervical spine surgery

Background contextVertebral artery injuries (VAIs) are rare but serious complications of cervical spine surgery, with the potential to cause catastrophic bleeding, permanent neurologic impairment, and even death. The present literature regarding incidence of this complication largely comprises a single surgeon or small multicenter case series.PurposeWe sought to gather a large sample of high-volume surgeons to adequately characterize the incidence and risk factors for VAI, management strategies used, and patient outcomes after VAI.Study designThe study was constructed as a cross-sectional study comprising all cervical spine patients operated on by the members of the international Cervical Spine Research Society (CSRS).Patient sampleAll patients who have undergone cervical spine surgery by a current member of CSRS as of the spring of 2012.Outcome measuresFor each surgeon surveyed, we collected self-reported measures to include the number of cervical cases performed in the surgeon's career, the number of VAIs encountered, the stage of the case during which the injury occurred, the management strategies used, and the overall patient outcome after injury.MethodsAn anonymous 10-question web-based survey was distributed to the members of the CSRS. Statistical analysis was performed using Student t tests for numerical outcomes and chi-squared analysis for categorical variables.ResultsOne hundred forty-one CSRS members (of 195 total, 72%) responded to the survey, accounting for a total of 163,324 cervical spine surgeries performed. The overall incidence of VAI was 0.07% (111/163,324). Posterior instrumentation of the upper cervical spine (32.4%), anterior corpectomy (23.4%), and posterior exposure of the cervical spine (11.7%) were the most common stages of the case to result in an injury to the vertebral artery. Discectomy (9%) and anterior exposure of the spine (7.2%) were also common time points for an arterial injury. One-fifth (22/111) of all VAI involved an anomalous course of the vertebral artery. The most common management of VAI was by direct tamponade. The outcomes of VAIs included no permanent sequelae in 90% of patients, permanent neurologic sequelae in 5.5%, and death in 4.5%. Surgeons at academic and private centers had nearly identical rates of VAIs. However, surgeons who had performed 300 or fewer cervical spine surgeries in their career had a VAI incidence of 0.33% compared with 0.06% in those with greater than 300 lifetime cases (p=.028).ConclusionsThe overall incidence of VAI during cervical spine surgery reported from this survey was 0.07%. Less experienced surgeons had a higher rate of VAI compared with their more experienced peers. The results of VAI are highly variable, resulting in no permanent harm most of the time; however, permanent neurologic injury or death occur in 10% of cases.     

Celecoxib and rofecoxib potentiate chronic colitis and premalignant changes in interleukin 10 knockout mice

Nonsteroidal anti-inflammatory drugs decrease sporadic colorectal carcinoma and adenomas in patients with familial adenomatous polyposis and in rodent models of sporadic colon cancer and familial adenomatous polyposis. Similarly, selective cyclooxygenase 2 inhibitors decrease adenomas in humans and rodents. However, their effects on chronic colitis and colitis-associated neoplasia are unknown. Interleukin 10-/- mice (C57/B6) were fed regular chow (n = 20) or chow with celecoxib (1,500 ppm, n = 18) or rofecoxib (75 ppm, n = 20) for 12 weeks. Twenty-eight percent of the celecoxib group died versus 5% of the control and rofecoxib groups (p < 0.05 compared with control). Celecoxib and rofecoxib increased the incidence of colitis (26% vs. 92% and 68%, p < 0.01), colitis score (0.4 +/- 0.2 vs. 2.5 +/- 0.3 and 2 +/- 0.4, p < 0.01), aberrant crypt foci (0.5 +/- 0.3 vs. 3.7 +/- 2.6 and 2.8 +/- 0.7, p < 0.01), aberrant crypts per mouse (4.11 +/- 2.1 vs. 41.2 +/- 9.7 and 27.1 +/- 7.5, p < 0.01) and dysplasia (11% vs. 54% and 42%, p < 0.01). Similarly, indomethacin (9 ppm, n = 15) increased colitis score, aberrant crypt foci, and dysplasia after 27 days of treatment. Two selective cyclooxygenase 2 inhibitors exacerbate colitis and premalignant changes in the interleukin 10-/- mouse model of chronic colitis and colitis-associated colon carcinoma.     

Worldwide trends in quantity and quality of published articles in the field of infectious diseases

Background  

Trying to confront with the widespread burden of infectious diseases, the society worldwide invests considerably on research. We evaluated the contribution of different world regions in research production in Infectious Diseases.