Ultrasound and Doppler findings in a rare case of Castleman's disease of the parotid

Castleman''s disease of the parotid gland is an extremely rare entity, with fewer than 20 cases reported in world literature so far and only 1 previous case report describing the ultrasound findings. The Doppler findings of parotid Castleman''s disease have never been described before to the best of the authors'' knowledge. This report describes the ultrasonographic and Doppler findings in a histopathologically proven case of Castleman''s disease of the left parotid gland in a young man.     

Platelet-activating factor receptor (PAF-R)-dependent pathways control tumour growth and tumour response to chemotherapy

Background  

Phagocytosis of apoptotic cells by macrophages induces a suppressor phenotype. Previous data from our group suggested that this occurs via Platelet-activating factor receptor (PAF-R)-mediated pathways. In the present study, we investigated the impact of apoptotic cell inoculation or induction by a chemotherapeutic agent (dacarbazine, DTIC) on tumour growth, microenvironmental parameters and survival, and the effect of treatment with a PAF-R antagonist (WEB2170). These studies were performed in murine tumours: Ehrlich Ascitis Tumour (EAT) and B16F10 melanoma.     

Evidence that fibrinogen γ′ directly interferes with protofibril growth: implications for fibrin structure and clot stiffness

Summary. Background: Fibrinogen contains an alternatively spliced γ‐chain (γ′), which mainly exists as a heterodimer with the common γA‐chain (γA/γ′). Fibrinogen γ′ has been reported to inhibit thrombin and modulate fibrin structure, but the underlying mechanisms are unknown. Objective: We aimed to investigate the molecular mechanism underpinning the influence of γ′ on fibrin polymerization, structure and viscoelasticity. Methods: γA/γA and γA/γ′ fibrinogens were separated using anion exchange chromatography. Cross‐linking was controlled with purified FXIIIa and a synthetic inhibitor. Fibrin polymerization was analyzed by turbidity and gel‐point time was measured using a coagulometer. We used atomic force microscopy (AFM) to image protofibril formation while final clot structure was assessed by confocal and scanning electron microscopy. Clot viscoelasticity was measured using a magnetic microrheometer. Results: γA/γ′ fibrin formed shorter oligomers by AFM than γA/γA, which in addition gelled earlier. γA/γ′ clots displayed a non‐homogenous arrangement of thin fibers compared with the uniform arrangements of thick fibers for γA/γA clots. These differences in clot structure were not due to thrombin inhibition as demonstrated in clots made with reptilase. Non‐cross‐linked γA/γA fibrin was approximately 2.7 × stiffer than γA/γ′. Cross‐linking by FXIIIa increased the stiffness of both fibrin variants; however, the difference in stiffness increased to approximately 4.6 × (γA/γA vs. γA/γ′). Conclusions: Fibrinogen γ′ is associated with the formation of mechanically weaker, non‐uniform clots composed of thin fibers. This is caused by direct disruption of protofibril formation by γ′.     

Mucositis: biology and management

PURPOSE OF REVIEW: Oral mucositis is a common regimen-limiting toxicity of radiation therapy and concomitant radiosensitizing chemotherapy for treatment of head and neck cancers. In addition to its symptomatic impact, oral mucositis increases the likelihood of unplanned breaks or delays in treatment, reduction in chemotherapy dose, use of feeding tube placement or total parenteral nutrition, the need for an intravenous line, opioid use and hospitalization. RECENT FINDINGS: Recent research has demonstrated that chemoradiation-induced mucosal injury is the result of a complex series of biological and cellular events that take place predominantly in the submucosa, with the epithelium being the target tissue. From these findings, novel biologically based preventive treatments are being developed, with a number of agents currently in clinical trials. The implications of recent advancements in radiation therapy treatment planning and delivery are also considered. SUMMARY: Mucositis is a common and serious complication secondary to chemoradiotherapy for head and neck cancer that has a profound effect on morbidity, compliance and treatment outcomes. Currently available interventions are directed at minimizing local radiation exposure and providing symptomatic relief. In the near future, a number of new treatment modalities can be expected to be introduced for reduction of severity and duration of mucositis.     

Age-related macular degeneration after retinal detachment surgery

We studied a group of 157 patients who had retinal detachment surgery in one eye with successful anatomical reattachment and a fellow eye without a retinal detachment. In a group of 7 out of 8 patients who had a retinal detachment that included the macula and who underwent surgery, we found that the development of macular degenerative changes was much less pronounced in the operated eye than in the fellow, control eye. In a group of 3 patients who had retinal detachment without macular involvement, the appearance of macular degenerative changes appeared to be rather symmetric in the operated and in the fellow eye. The presence of a circling buckle did not appear to have an influence on the ARMD changes. It appears that the presence of a macular detachment is a factor in modifying the natural history of age-related macular degeneration. The diminution of signs of ARMD could be related to a degree of atrophy in the retinal pigment epithelium occurring after a retinal detachment with the macula off.