Posterozentraler Zugang zum dorsalen Tibiakopf

Background

For surgical treatment of posterior shearing tibial plateau fractures and avulsion fractures of the posterior cruciate ligament (PCL) a posterocentral approach without dissection or separation of the heads of the gastrocnemius muscle is used. The aim of this study was an evaluation of this approach.

Patients and methods

From 2001-2012 a total of 33 patients were surgically treated using a posterocentral approach to the dorsal knee joint. Of these patients 22 had a posterior shearing tibial plateau fracture and 11 had an avulsion fracture of the PCL. The fracture type, complications, expertise of the surgeon, fracture healing, implant position and irritation, nerve lesions, scar tissue and range of motion were documented.

Results

Hypesthesia around the scar, at the lateral foot and lower lateral leg were observed in one each of three patients. Despite two ventral implant infections no infection of the dorsal implant occurred. All scar tissue was without pathological findings and scar contracture was not observed. In three cases the screw tips at the anterior proximal tibia were palpable but without complaints from the patients.

Conclusions

The posterocentral approach showed a low complication rate in the hands of experienced surgeons. The soft tissue cover seems to prevent implant infections.     

The 2011 Japanese earthquake: an overview of environmental health impacts

A magnitude 9.0 earthquake rupturing the Earth's crust nearly 130 km off the east coast of Japan on March 11, 2011, triggered a tsunami that reached the Japanese coast approximately 30 minutes later. The combined effects of the earthquake and tsunami (known as the Tohoku event) devastated the area of northeast Japan, resulting in widespread infrastructure destruction, loss of life, and environmental contamination. Perhaps the longest-lasting impact of the Tohoku event will result from the damage to the nuclear power plants along the coast and the subsequent release of radioactive elements into the environment. This article describes the environmental impacts of the disaster and highlights the interconnectedness among the core areas of environmental health including air quality, water quality, weather/climate change, food safety, healthy housing, waste/sanitation, infectious disease/vector control, radiation, injury prevention, emergency preparedness, and toxicology. The purpose of this article is to provide an overview of the spectrum of the natural disaster and its environmental health impact to the human population. Future scientific analysis may confirm or challenge the information presented here.     

Interaction of Chemokine Receptor CCR5 with its Ligands: Multiple Domains for HIV-1 gp120 Binding and a Single Domain for Chemokine Binding

CCR5 is a chemokine receptor expressed by T cells and macrophages, which also functions as the principal coreceptor for macrophage (M)-tropic strains of HIV-1. To understand the molecular basis of the binding of chemokines and HIV-1 to CCR5, we developed a number of mAbs that inhibit the various interactions of CCR5, and mapped the binding sites of these mAbs using a panel of CCR5/CCR2b chimeras. One mAb termed 2D7 completely blocked the binding and chemotaxis of the three natural chemokine ligands of CCR5, RANTES (regulated on activation normal T cell expressed and secreted), macrophage inflammatory protein (MIP)-1α, and MIP-1β, to CCR5 transfectants. This mAb was a genuine antagonist of CCR5, since it failed to stimulate an increase in intracellular calcium concentration in the CCR5 transfectants, but blocked calcium responses elicited by RANTES, MIP-1α, or MIP-1β. This mAb inhibited most of the RANTES and MIP-1α chemotactic responses of activated T cells, but not of monocytes, suggesting differential usage of chemokine receptors by these two cell types. The 2D7 binding site mapped to the second extracellular loop of CCR5, whereas a group of mAbs that failed to block chemokine binding all mapped to the NH₂-terminal region of CCR5. Efficient inhibition of an M-tropic HIV-1–derived envelope glycoprotein gp120 binding to CCR5 could be achieved with mAbs recognizing either the second extracellular loop or the NH₂-terminal region, although the former showed superior inhibition. Additionally, 2D7 efficiently blocked the infectivity of several M-tropic and dual-tropic HIV-1 strains in vitro. These results suggest a complicated pattern of HIV-1 gp120 binding to different regions of CCR5, but a relatively simple pattern for chemokine binding. We conclude that the second extracellular loop of CCR5 is an ideal target site for the development of inhibitors of either chemokine or HIV-1 binding to CCR5.