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Trong nghiên cứu này, vật liệu nghiên cứu là than bùn được hoạt hóa bằng H3PO4 ở nồng độ 2,0 M. Các mẫu sau khi tổng hợp được đặc trưng bởi một số phương pháp như EDX, XRD, SEM, BET và FTIR. Tính chất hấp phụ của vật liệu được đánh giá thông qua khả năng loại bỏ ion Cd2+ trong dung dịch nước. Đặc trưng vật liệu cho thấy mẫu than bùn sau khi hoạt hóa có diện tích bề mặt riêng và độ xốp cao hơn so với mẫu than bùn thô. Nghiên cứu cho thấy dữ liệu thực nghiệm hấp phụ ion Cd2+ trên than bùn được hoạt hóa được mô tả tốt đồng thời bởi cả hai mô hình đẳng nhiệt Langmuir và Freundlich, tuy nhiên mô hình đẳng nhiệt Langmuir tỏ ra phù hợp hơn. Vật liệu than bùn được hoạt hóa đạt dung lượng hấp phụ cực đại qm 29,07 mg/g. Ngoài ra nghiên cứu còn cho thấy sự hấp phụ ion Cd2+ trên than bùn hoạt hóa tuân theo mô hình động học biểu kiến bậc 2. Từ những kết quả nghiên cứu trên cho thấy vật liệu hấp phụ từ than bùn có nhiều tiềm năng trong việc loại bỏ các ion kim loại nặng trong dung dịch nước.

Although it is known that MEKK4 regulates MKK6, and p38 MAP kinase, extracellular stimuli that activate the serine/threonine kinase, MEKK4, are unknown. The aim of this study was then to identify stimuli that regulate MEKK4. By using recombinant MEKK4, as bait to attract interacting proteins, the calcium binding protein, annexin II, was identified by mass spectrometry as interacting with MEKK4, suggesting that MEKK4 might be regulated by calcium. A calcium-dependent interaction between MEKK4 and annexin II was observed when MEKK4 was immunoprecipitated from rat aortic smooth muscle cells that were treated with angiotensin II. Additional studies using recombinant MEKK4 in a Far-Western immunoblot identified a protein of 120 kDa as interacting directly with MEKK4. Prior studies indicated that MEKK4 was phosphorylated on tyrosine in vivo, and in fact, Pyk2 interacts with MEKK4 in an angiotensin II dependent manner in rat aortic smooth muscle cells. Pyk2 phosphorylates MEKK4 in vitro and Pyk2-dependent phosphorylation further regulates MEKK4-dependent phosphorylation of MKK6. Finally, dominant-negative MEKK4 inhibits angiotensin II mediated transcription of a luciferase reporter construct containing the cyclooxygenase II promoter, demonstrating that MEKK4 functions in a calcium-dependent manner as a substrate for Pyk2 and regulates transcription of cyclooxygenase II.

From 1996 onward, a pandemic spread of Vibrio parahaemolyticus infections due to one clone has been reported in several Asian countries. During a population-based study that relied on passive surveillance, 548 cases of V. parahaemolyticus infection were detected between 1997 and 1999 in the Khanh Hoa province of Vietnam. Detection of cases of V. parahaemolyticus infection abruptly stopped in November 1999, although Vibrio species other than V. parahaemolyticus continued to be isolated throughout 2000. Of the infections, 90% occurred in individuals >5 years old; 53% of the patients presented with watery stools, and 6% reported blood in their stools. All patients had recovered by the time of discharge. A surprising risk factor for V. parahaemolyticus infections was high socioeconomic status. Like the interruption of the transmission of V. cholerae infections that had been observed earlier, the transmission of V. parahaemolyticus came to a halt without meteorological changes or changes in water supply and sanitation.

Policy decisions regarding whether to incorporate new vaccines into routine public health practice in developing countries will depend in part on the costs of vaccine purchase and of vaccine delivery. In March, 1997, a large-scale effectiveness trial of a locally produced, orally administered bivalent vaccine against Vibrio cholerae 01 and 0139 began in Viet Nam. Empirical data obtained from the trial was used to determine the costs of the immunization campaign from the government perspective. The study population, including the children less than one year of age and pregnant women who were ineligible for immunization, was 353926. A total of 289041 persons received two doses of vaccine, and 13340 persons received one dose of vaccine. Two-dose vaccine coverage was 83.4%. The total cost of vaccine delivery during the immunization campaign was $66527. The cost of each dose of vaccine was $0.31. Therefore, the total cost of the immunization campaign was $0.44 per dose administered, and $0.91 per fully immunized person. Attempts to reduce the cost per dose of vaccine (e.g. the use of a monovalent vaccine against serogroup 01) are likely to have a large impact on the cost of future similar immunization campaigns.