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Anuj Shrestha Zeeshan Jawa Kathryn L. Koch Amy B. Rankin Qun Xiang Anand Padmanabhan Matthew S. Karafin Joshua J. Field 《Journal of clinical apheresis》2015,30(6):353-358
Red cell exchange (RCE) is a common procedure in adults with sickle cell disease (SCD). Implantable dual lumen Vortex (DLV) ports can be used for RCE in patients with poor peripheral venous access. We performed a retrospective cohort study of RCE procedures performed in adults with SCD. The main objective of the study was to compare the inlet speed, duration of procedures and rate of complications performed through DLV ports to those performed through temporary central venous and peripheral catheters. Twenty‐nine adults with SCD underwent a total of 318 RCE procedures. Twenty adults had DLV ports placed and 218 procedures were performed using DLV ports. Mean length of follow‐up after DLV port placement was 397 ± 263 days. Six DLV ports were removed due to infection and 1 for malfunction after a mean of 171 ± 120 days. Compared to temporary central venous and peripheral catheters, DLV port procedures had a greater rate of procedural complications, a longer duration, and a lower inlet speed (all P < 0.01). When accounting for the maximum allowable inlet speed to avoid citrate toxicity, 40% of DLV port procedures were greater than 10% below maximum speed, compared to 7 and 14% of procedures performed through temporary central venous and peripheral catheters (P < 0.0001). In conclusion, DLV ports can be used for RCE in adults with SCD, albeit with more procedural complications and longer duration. The smaller internal diameter and longer catheter of DLV ports compared to temporary central venous catheters likely accounts for the differences noted. J. Clin. Apheresis 30:353–358, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
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Krishna Pillai Javid Akhter Terence C. Chua Mena Shehata Nayef Alzahrani Issan Al-Alem David L. Morris 《Medicine》2015,94(9)
Thermal ablation of liver tumors near large blood vessels is affected by the cooling effect of blood flow, leading to incomplete ablation. Hence, we conducted a comparative investigation of heat sink effect in monopolar (MP) and bipolar (BP) radiofrequency ablation (RFA), and microwave (MW) ablation devices.With a perfused calf liver, the ablative performances (volume, mass, density, dimensions), with and without heat sink, were measured. Heat sink was present when the ablative tip of the probes were 8.0 mm close to a major hepatic vein and absent when >30 mm away. Temperatures (T1 and T2) on either side of the hepatic vein near the tip of the probes, heating probe temperature (T3), outlet perfusate temperature (T4), and ablation time were monitored.With or without heat sink, BP radiofrequency ablated a larger volume and mass, compared with MP RFA or MW ablation, with latter device producing the highest density of tissue ablated. MW ablation produced an ellipsoidal shape while radiofrequency devices produced spheres.Percentage heat sink effect in Bipolar radiofrequency : Mono-polar radiofrequency : Microwave was (Volume) 33:41:22; (mass) 23:56:34; (density) 9.0:26:18; and (relative elipscity) 5.8:12.9:1.3, indicating that BP and MW devices were less affected.Percentage heat sink effect on time (minutes) to reach maximum temperature (W) = 13.28:9.2:29.8; time at maximum temperature (X) is 87:66:16.66; temperature difference (Y) between the thermal probes (T3) and the temperature (T1 + T2)/2 on either side of the hepatic vessel was 100:87:20; and temperature difference between the (T1 + T2)/2 and temperature of outlet circulating solution (T4), Z was 20.33:30.23:37.5.MW and BP radiofrequencies were less affected by heat sink while MP RFA was the most affected. With a single ablation, BP radiofrequency ablated a larger volume and mass regardless of heat sink. 相似文献
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Zaida Araujo Sietze Brandes Elena Pinelli María A. Bochichio Andrea Palacios Albina Wide Bruno Rivas-Santiago Juan Carlos Jiménez 《Revista do Instituto de Medicina Tropical de S?o Paulo》2015,57(1):47-55
The present study aimed at measuring seropositivities for infection by
Ascaris suum and Toxocara canis using the
excretory/secretory (E/S) antigens from Ascaris suum (AES) and
Toxocara canis (TES) within an indigenous population. In
addition, quantification of cytokine expressions in peripheral blood cells was
determined. A total of 50 Warao indigenous were included; of which 43 were adults and
seven children. In adults, 44.1% were seropositive for both parasites; whereas
children had only seropositivity to one or the other helminth. For ascariosis, the
percentage of AES seropositivity in adults and children was high; 23.3% and 57.1%,
respectively. While that for toxocariosis, the percentage of TES seropositivity in
adults and children was low; 9.3% and 14.3%, respectively. The percentage of
seronegativity was comparable for AES and TES antigens in adults (27.9%) and children
(28.6%). When positive sera were analyzed by Western blotting technique using AES
antigens; three bands of 97.2, 193.6 and 200.2 kDas were mostly recognized. When the
TES antigens were used, nine major bands were mostly identified; 47.4, 52.2, 84.9,
98.2, 119.1, 131.3, 175.6, 184.4 and 193.6 kDas. Stool examinations showed that
Blastocystis hominis, Hymenolepis nana and
Entamoeba coli were the most commonly observed intestinal
parasites. Quantification of cytokines IFN-γ, IL-2, IL-6, TGF-β, TNF-α, IL-10 and
IL-4 expressions showed that there was only a significant increased expression of
IL-4 in indigenous with TES seropositivity (p < 0.002).
Ascaris and Toxocara seropositivity was
prevalent among Warao indigenous. 相似文献
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Past research suggests that as many as 50% of onward human immunodeficiency virus (HIV) transmissions occur during acute and recent HIV infection. It is clearly important to develop interventions which focus on this highly infectious stage of HIV infection to prevent further transmission in the risk networks of acutely and recently infected individuals. Project Protect tries to find recently and acutely infected individuals and prevents HIV transmission in their risk networks. Participants are recruited by community health outreach workers at community-based HIV testing sites and drug users' community venues, by coupon referrals and through referrals from AIDS clinics. When a network with acute/recent infection is identified, network members are interviewed about their risky behaviors, network information is collected, and blood is drawn for HIV testing. Participants are also educated and given prevention materials (condoms, syringes, educational materials); HIV-infected participants are referred to AIDS clinics and are assisted with access to care. Community alerts about elevated risk of HIV transmission are distributed within the risk networks of recently infected. Overall, 342 people were recruited to the project and screened for acute/recent HIV infection. Only six index cases of recent infection (2.3% of all people screened) were found through primary screening at voluntary counseling and testing (VCT) sites, but six cases of recent infection were found through contact tracing of these recently infected participants (7% of network members who came to the interview). Combining screening at VCT sites and contact tracing the number of recently infected people we located as compared to VCT screening alone. No adverse events were encountered. These first results provide evidence for the theory behind the intervention, i.e., in the risk networks of recently infected people there are other people with recent HIV infection and they can be successfully located without increasing stigma for project participants. 相似文献