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Artificial insemination (AI) is widely used in livestock industries to breed for desirable characteristics and increase yields. The standard practice of storing and transporting bovine semen uses liquid nitrogen (LN), a scarce commodity in many regions of the world. This study explored the feasibility of using dry ice, a more readily available alternative. We developed equipment that dispenses dry ice from widely available liquid carbon dioxide (LCO2) tanks into an easily transportable device. In vivo fertility results with a dry ice cold chain showed no statistical difference to the conventional LN method. In vitro bovine semen analyses also showed that storage under these conditions minimally affects characteristics associated with fertility. A dry ice cold chain system could leverage the global availability of LCO2 to expand the reach of AI and other cold storage applications of biological materials in low-resource settings.

Central venous catheters (CVCs), placed in the Superior Vena Cava (SVC) for hemodialysis or chemotherapy, are routinely filled while not in use with heparin, an anticoagulant, to maintain patency and prevent thrombus formation at the catheter tip. The heparin-locking procedure, however, places the patient at risk for systemic bleeding, as heparin is known to leak from the catheter into the blood stream. We provide evidence from detailed in-vitro experiments that shows the driving mechanism behind heparin leakage to be convective-diffusive transport due to the pulsatile flow surrounding the catheter. This novel mechanism is supported by experimental planar laser induced fluorescence (PLIF) and particle image velocimetry (PIV) measurements of flow velocity and heparin transport from a CVC placed inside a model SVC inside a pulsatile flow loop. The results predict an initial, fast (< 10s), convection-dominated phase that rapidly depletes the concentration of heparin in the near-tip region, the region of the catheter with side holes. This is followed by a slow, diffusion-limited phase inside the catheter lumen, where the concentration is still high, that is insufficient at replenishing the lost heparin concentration in the near-tip region. The results presented here, which are consistent with previous in vivo estimates of 24-hour leakage rates, predict that the concentration of heparin in the near-tip region is essentially zero for the majority of the interdialytic phase, rendering the heparin locking procedure ineffective.

Developing countries are facing a significant challenge to sustain their healthcare in the face of changing diseases, as well as an overwhelming and difficult economic climate. In numerous countries, economic evaluation is increasingly advocated as a tool to ensure the efficient use of resources. Taking the use of the insulin analogue as an example of predominant disease, this chapter systematically reviewed the state-of-the-art publications of economic evaluation studies in developing countries. Economic evaluation studies published until September 30, 2015, were identified from major databases and Health Technology Assessment agency reports. Only six studies were included in the final analysis. They only evaluated biphasic and long-acting insulin analogues, covering seven developing countries. There is moderate evidence of cost-effectiveness regarding biphasic and long-acting insulin analogues for type 2 diabetic patients in developing countries. However, there is a substantial gap concerning the published studies and their reporting quality, which calls for concerted efforts for developing countries to improve their capacity of conducting and employing economic evaluation studies.