Patient Outcomes and Cerebral Infarction after Ruptured Anterior Communicating Artery Aneurysm Treatment.

BACKGROUND AND PURPOSE: Anterior communicating artery aneurysm rupture and treatment is associated with high rates of dependency, which are more severe after clipping compared with coiling. To determine whether ischemic injury might account for these differences, we characterized cerebral infarction burden, infarction patterns, and patient outcomes after surgical or endovascular treatment of ruptured anterior communicating artery aneurysms. MATERIALS AND METHODS: We performed a retrospective cohort study of consecutive patients with ruptured anterior communicating artery aneurysms. Patient data and neuroimaging studies were reviewed. A propensity score for outcome measures was calculated to account for the nonrandom assignment to treatment. Primary outcome was the frequency of frontal lobe and striatum ischemic injury. Secondary outcomes were patient mortality and clinical outcome at discharge and at 3 months. RESULTS: Coiled patients were older (median, 55 versus 50 years; P = .03), presented with a worse clinical status (60% with Hunt and Hess Score >2 versus 34% in clipped patients; P = .02), had a higher modified Fisher grade (P = .01), and were more likely to present with intraventricular hemorrhage (78% versus 56%; P = .03). Ischemic frontal lobe infarction (OR, 2.9; 95% CI, 1.1-8.4; P = .03) and recurrent artery of Heubner infarction (OR, 20.9; 95% CI, 3.5-403.7; P < .001) were more common in clipped patients. Clipped patients were more likely to be functionally dependent at discharge (OR, 3.2; P = .05) compared with coiled patients. Mortality and clinical outcome at 3 months were similar between coiled and clipped patients. CONCLUSIONS: Frontal lobe and recurrent artery of Heubner infarctions are more common after surgical clipping of ruptured anterior communicating artery aneurysms, and are associated with poorer clinical outcomes at discharge.

Salivary gland adenoid cystic carcinoma: a review of chemotherapy and molecular therapies.

Adenoid cystic carcinoma (ACC) accounts for about 1% of all head and neck malignancies. It has a tendency for a prolonged clinical course, with local recurrences and distant metastases sometimes occurring many years after presentation. Standard treatment for salivary gland ACC is surgery and post-operative radiotherapy. The aim of this review was to examine the reported efficacy of various chemotherapy regimens and molecular therapies on recurrent/metastatic salivary gland ACC. One hundred and fourteen publications were reviewed on chemotherapy as well as possible molecular targets of therapy, including KIT, epidermal growth factor receptor (EGFR), human epidermal growth receptor-2 (HER-2), oestrogen and progesterone receptors, proliferating cell nuclear antigen (PCNA), Ki-67 and the p53, bcl-2 and SOX-4 genes. Reported response rates to combination chemotherapy are low and response duration generally short lived. The response to molecular therapies is low also. More research into novel molecular targets is needed.

Recoverin regulates light-dependent phosphodiesterase activity in retinal rods.

The Ca2+-binding protein recoverin may regulate visual transduction in retinal rods and cones, but its functional role and mechanism of action remain controversial. We compared the photoresponses of rods from control mice and from mice in which the recoverin gene was knocked out. Our analysis indicates that Ca2+-recoverin prolongs the dark-adapted flash response and increases the rod's sensitivity to dim steady light. Knockout rods had faster Ca2+ dynamics, indicating that recoverin is a significant Ca2+ buffer in the outer segment, but incorporation of exogenous buffer did not restore wild-type behavior. We infer that Ca2+-recoverin potentiates light-triggered phosphodiesterase activity, probably by effectively prolonging the catalytic activity of photoexcited rhodopsin.

Prolonged photoresponses in transgenic mouse rods lacking arrestin.

Arrestins are soluble cytoplasmic proteins that bind to G-protein-coupled receptors, thus switching off activation of the G protein and terminating the signalling pathway that triggers the cellular response. Although visual arrestin has been shown to quench the catalytic activity of photoexcited, phosphorylated rhodopsin in a reconstituted system, its role in the intact rod cell remains unclear because phosphorylation alone reduces the catalytic activity of rhodopsin. Here we have recorded photocurrents of rods from transgenic mice in which one or both copies of the arrestin gene were disrupted. Photoresponses were unaffected when arrestin expression was halved, indicating that arrestin binding is not rate limiting for recovery of the rod photoresponse, as it is in Drosophila. With arrestin absent, the flash response displayed a rapid partial recovery followed by a prolonged final phase. This behaviour indicates that an arrestin-independent mechanism initiates the quench of rhodopsin's catalytic activity and that arrestin completes the quench. The intensity dependence of the photoresponse in rods lacking arrestin further suggests that, although arrestin is required for normal signal termination, it does not participate directly in light adaptation.

Multiple visual pigments in a photoreceptor of the salamander retina.

Although a given retina typically contains several visual pigments, each formed from a retinal chromophore bound to a specific opsin protein, single photoreceptor cells have been thought to express only one type of opsin. This design maximizes a cell's sensitivity to a particular wavelength band and facilitates wavelength discrimination in retinas that process color. We report electrophysiological evidence that the ultraviolet-sensitive cone of salamander violates this rule. This cell contains three different functional opsins. The three opsins could combine with the two different chromophores present in salamander retina to form six visual pigments. Whereas rods and other cones of salamander use both chromophores, they appear to express only one type of opsin per cell. In visual pigment absorption spectra, the bandwidth at half-maximal sensitivity increases as the pigment's wavelength maximum decreases. However, the bandwidth of the UV-absorbing pigment deviates from this trend; it is narrow like that of a red-absorbing pigment. In addition, the UV-absorbing pigment has a high apparent photosensitivity when compared with that of red- and blue-absorbing pigments and rhodopsin. These properties suggest that the mechanisms responsible for spectrally tuning visual pigments separate two absorption bands as the wavelength of maximal sensitivity shifts from UV to long wavelengths.