Effect of various incremental techniques on the marginal adaptation of class II composite resin restorations.

The effects of various placement techniques on the formation of microgaps were compared at the gingival margins of class II composite resin restorations. Three incremental techniques (occlusogingival layering, oblique layering, and faciolingual layering) and two one-bulk techniques of placing composite resin were studied. In the first one-bulk placement technique the composite resin was photocured occlusally; in the second one-bulk technique the composite resin was irradiated from three directions; facial, lingual, and occlusal. None of the incremental placement techniques improved the adaptation at the gingival margin compared with a one-bulk technique irradiated occlusally. However, the one-bulk placement technique that was irradiated from three directions created a substantial marginal discrepancy.     

International validation of the prognostic value of lymphovascular invasion in patients treated with radical cystectomy

Study Type – Prognosis (retrospective cohort)
Level of Evidence 2b

OBJECTIVE

To externally validate the prognostic value of lymphovascular invasion (LVI) in a large international cohort of patients treated with radical cystectomy (RC) for urothelial carcinoma of the bladder (UCB).

PATIENTS AND METHODS

We collected data from 4257 patients treated with RC and pelvic lymphadenectomy for UCB, without neoadjuvant chemotherapy, at 12 centres. LVI was defined as presence of nests of tumour cells within an endothelium‐lined space.

RESULTS

LVI was detected in 1407 patients (33.1%); the proportion of LVI increased with advancing stage, higher grade, soft‐tissue surgical margin involvement, and lymph node metastasis (P < 0.001 for all). In standard multivariate models, LVI was associated with both disease recurrence (hazard ratio 1.43, P < 0.001) and cancer‐specific mortality (1.45, P < 0.001). In the entire cohort, adding LVI to a base model that included standard features improved only minimally its predictive accuracy for both recurrence and cancer‐specific mortality (by 1.1% and 1.2%, respectively). In 3122 patients with negative lymph nodes, LVI remained independently associated with and improved the predictive accuracy of the standard predictors for recurrence (hazard ratio 1.68, P < 0.001; +2.3%) and cancer‐specific mortality (1.70, P < 0.001; +2.4%). By contrast, in 1071 node‐positive patients, LVI only marginally improved the prediction of cancer‐specific recurrence (hazard ratio 1.20, P < 0.001; +0.2%) and survival (1.23, P < 0.001; +0.5%).

CONCLUSIONS

LVI is strongly associated with clinical outcome in node‐negative patients treated with RC. The assessment of LVI might help to identify patients who could benefit from adjuvant therapy after RC. After confirmation in different populations, LVI should be included in the staging of UCB.     

Rodent Osteoblastic Cells Express Voltage-Sensitive Calcium Channels Lacking a γ Subunit

Voltage-sensitive calcium channels (VSCC) open in response to external stimuli, including calcitropic hormones, that alter plasma membrane calcium (Ca²⁺) permeability. Ca²⁺ that enters the cell through these channels serves a second messenger function, eliciting cellular responses that include secretion and changes in gene expression. In osteoblasts, VSCCs serve as key regulators of Ca²⁺ permeability and are a major class of calcitropic hormone-sensitive Ca²⁺ channels present in the plasma membrane. The members of the VSCC family exist as a complex of polypeptide subunits that are comprised of a pore-forming ₁ subunit, an intracellular subunit, a dimer of disulfide-linked ₂ and subunits, and in some tissues, a subunit. Previous studies in our laboratory have shown that the major functional ₁ subunit present in osteoblasts is the _1C (Ca_V1.2). To determine the complement of auxiliary subunits present in rodent osteoblastic cells, we employed RT-PCR using a battery of subunit specific primers and appropriate tissue controls. Immunohistochemistry also was performed, using available subunit specific antibodies, to measure protein expression and localization. Cell types examined included MC3T3-E1 at various stages of differentiation, ROS 17/2.8 osteosarcoma, and primary cultures of rat calvarial osteoblasts. The results indicate that all cells expressed multiple subunit classes and ₂ dimers, but no subunits, regardless of differentiation state. We propose a structure for the functional osteoblast VSCC that consists of ₁, , ₂ subunits and is devoid of a subunit.