The early response to a novel coronavirus in the Middle East.

The detection of a novel coronavirus in patients from the Arabian Peninsula in late 2012 raised serious concerns of a possible international outbreak. Ministries of health of the three affected countries invited missions from the World Health Organization to participate in a review of data and capacity to detect and respond to further cases. Recommendations were made for investigations to answer critical questions about human-to-human transmission and the geographic extent of the virus. Additional recommendations were made to improve surveillance capacity by acquiring the capacity to test for the virus and enhance syndromic surveillance. Available evidence continues to suggest an unknown animal reservoir for the virus with sporadic zoonotic transmission the primary epidemiological pattern of transmission. Human-to-human transmission, while it can occur, does not appear to be sustained in the community.

The early response to a novel coronavirus in the Middle East

The detection of a novel coronavirus in patients from the Arabian Peninsula in late 2012 raised serious concerns of a possible international outbreak. Ministries of health of the three affected countries invited missions from the World Health Organization to participate in a review of data and capacity to detect and respond to further cases. Recommendations were made for investigations to answer critical questions about human-to human transmission and the geographic extent of the virus. Additional recommendations were made to improve surveillance capacity by acquiring the capacity to test for the virus and enhance syndromic surveillance. Available evidence continues to suggest an unknown animal reservoir for the virus with sporadic zoonotic transmission as the primary epidemiological pattern of transmission. Human-to-human transmission, while it can occur, does not appear to be sustained in the community

Implications of the International Health Regulations (2005) for communicable disease surveillance systems: Tunisia's experience.

BACKGROUND: In May 2005, the revised International Health Regulations, known as IHR (2005), were adopted in response to the evolving nature of communicable diseases (CD) and the rapid increase in global trade and travel. CD surveillance is an integral part of a country's core requirements under the regulations. METHODS: The implications of these requirements were assessed as part of a review of the national CD surveillance system of Tunisia using a qualitative methodology of strengths, weaknesses, opportunities and threats (SWOT). RESULTS: Tunisia is some way towards meeting the requirements of IHR (2005) while some specific areas that need to be addressed are highlighted for improvement: standardization of surveillance documents, strengthening the role of the laboratory in surveillance, increased human resources and training. CONCLUSIONS: Tunisia's experience can offer some lessons to other countries in this process. While meeting the capacity obligations of IHR (2005) requires investment and commitment, this investment will enable countries to better protect themselves against public health emergencies arising within their borders and threatening from elsewhere in the world.

Injection practices in Burkina Faso in 2000.

BACKGROUND: Unsafe delivery and overuse of injections can result in the spread of hepatitis B virus, hepatitis C virus, and HIV. The aim of the present survey was to estimate the frequency of safe injection practices in Burkina Faso. METHOD: Using the new standardized World Health Organization tool to assess injection practices, we selected 80 primary health facilities with a two-stage cluster sampling method, collected information using structured observations and provider interviews, and analyzed the data using Epi-Info software. RESULTS: We observed 116 injections in 52 facilities. In 50 facilities [96%; 95% confidence interval (CI) 85-99%] injections were given with a new, single-use syringe and needle. In 29 facilities (56%; 95% CI 36-74%), staff recapped needles using two hands. All 80 facilities visited had a stock in the community to provide new, single-use syringes and needles. In 61% (95% CI 54-79%) of facilities, staff reported needlestick injuries in the last 12 months. Used needles were discarded in open containers in 66 facilities (83%; 95% CI 55-96%) and observed in the surroundings of 46 facilities (57%; 95% CI 32-80%). CONCLUSIONS: In 2000, most of the health facilities in Burkina Faso were using sterile injection equipment. However, practices were still observed that could expose patients, health care workers, and communities to risks, and that required specific interventions.

Development of a surveillance system for nosocomial infections: the component for neonatal intensive care units in Germany.

Neonates are at high risk of nosocomial infections and surveillance has been shown to be valuable for the reduction of nosocomial infections. The National Nosocomial Infections Surveillance (NNIS) system established in the US has a special surveillance component for neonatal intensive care units (NICUs) with some fairly specific methods. However, there are no specific definitions of nosocomial infections in this patient group. When creating a surveillance component for NICUs in Germany we therefore decided not to adopt merely all Centers for Disease Control and Prevention definitions and NNIS methods, but also to develop our own surveillance methods for this patient group. For this process four steps became necessary: (1)development of modified definitions for nosocomial infections and their evaluation; (2)testing the NNIS method in three NICUs with infection control nurses; (3)a pilot project for a surveillance component within the national surveillance system in Germany; and (4)establishment of a surveillance component within our national surveillance system. The system is now established in 33 hospital departments and 66 NICUs participate in the surveillance system. We have an overview of 3357 neonates in three birthweight groups. This article explains the reasons for the various steps, and the advantages and disadvantages of modification of the original NNIS methods and definitions.

An essential role for ectodomain shedding in mammalian development.

The ectodomains of numerous proteins are released from cells by proteolysis to yield soluble intercellular regulators. The responsible protease, tumor necrosis factor-alpha converting enzyme (TACE), has been identified only in the case when tumor necrosis factor-alpha (TNFalpha) is released. Analyses of cells lacking this metalloproteinase-disintegrin revealed an expanded role for TACE in the processing of other cell surface proteins, including a TNF receptor, the L-selectin adhesion molecule, and transforming growth factor-alpha (TGFalpha). The phenotype of mice lacking TACE suggests an essential role for soluble TGFalpha in normal development and emphasizes the importance of protein ectodomain shedding in vivo.

Crystal structure of the catalytic domain of human tumor necrosis factor-alpha-converting enzyme.

Tumor necrosis factor-alpha (TNFalpha) is a cytokine that induces protective inflammatory reactions and kills tumor cells but also causes severe damage when produced in excess, as in rheumatoid arthritis and septic shock. Soluble TNFalpha is released from its membrane-bound precursor by a membrane-anchored proteinase, recently identified as a multidomain metalloproteinase called TNFalpha-converting enzyme or TACE. We have cocrystallized the catalytic domain of TACE with a hydroxamic acid inhibitor and have solved its 2.0 A crystal structure. This structure reveals a polypeptide fold and a catalytic zinc environment resembling that of the snake venom metalloproteinases, identifying TACE as a member of the adamalysin/ADAM family. However, a number of large insertion loops generate unique surface features. The pro-TNFalpha cleavage site fits to the active site of TACE but seems also to be determined by its position relative to the base of the compact trimeric TNFalpha cone. The active-site cleft of TACE shares properties with the matrix metalloproteinases but exhibits unique features such as a deep S3' pocket merging with the S1' specificity pocket below the surface. The structure thus opens a different approach toward the design of specific synthetic TACE inhibitors, which could act as effective therapeutic agents in vivo to modulate TNFalpha-induced pathophysiological effects, and might also help to control related shedding processes.

Simplified preformed chelate protein radiolabeling with technetium-99m mercaptoacetamidoadipoylglycylglycine (N3S-adipate).

A simplified kiet has been developed for 99mTc protein radiolabeling using an N3S triamide mercaptide bifunctional chelating agent and the preformed chelate approach. The process combined N3S chelating agent, gluconate intermediate transfer agent, stannous reducing agent, and gentisic acid stabilizer into a lyophilized formulation. With sulfur donor atom hemithioacetal protection of the ligand, delta-2,3,5,6-tetrafluorothiophenyl alpha-S-(1-ethoxyethyl)mercaptoacetamido-L-adipoylglycylglycine , optimum 99mTc chelation was achieved in a single step. Subsequent reaction with NR-LU-10 antibody Fab fragment followed by purification via QAE Sephadex anion exchange resin filter afforded 99mTc-N3S-NR-LU-10 Fab conjugate with retained immunoreactivity and effective tumor targeting properties.

A metalloproteinase disintegrin that releases tumour-necrosis factor-alpha from cells.

Mammalian cells proteolytically release (shed) the extracellular domains of many cell-surface proteins. Modification of the cell surface in this way can alter the cell's responsiveness to its environment and release potent soluble regulatory factors. The release of soluble tumour-necrosis factor-alpha (TNF-alpha) from its membrane-bound precursor is one of the most intensively studied shedding events because this inflammatory cytokine is so physiologically important. The inhibition of TNF-alpha release (and many other shedding phenomena) by hydroxamic acid-based inhibitors indicates that one or more metalloproteinases is involved. We have now purified and cloned a metalloproteinase that specifically cleaves precursor TNF-alpha. Inactivation of the gene in mouse cells caused a marked decrease in soluble TNF-alpha production. This enzyme (called the TNF-alpha-converting enzyme, or TACE) is a new member of the family of mammalian adamalysins (or ADAMs), for which no physiological catalytic function has previously been identified. Our results should facilitate the development of therapeutically useful inhibitors of TNF-alpha release, and they indicate that an important function of adamalysins may be to shed cell-surface proteins.

Further evidence for a common mechanism for shedding of cell surface proteins.

Pro-TNF alpha, Steel factor, type II IL-1R and IL-2R alpha were expressed in COS-7 cells and the generation of their soluble forms was examined. The release of all four proteins was strongly stimulated by the phorbol ester PMA and completely blocked by a hydroxamate-based inhibitor of metalloproteases. COS-7 cell membranes were found to cleave various synthetic pro-TNF alpha peptides with the same specificity as a partially purified TNF alpha converting enzyme purified from human monocytic cells, suggesting that the same enzyme may be responsible for at least some of the COS-7 cell shedding activity.

Protection against a lethal dose of endotoxin by an inhibitor of tumour necrosis factor processing.

Tumour necrosis factor (tumour necrosis factor-alpha/cachectin) plays a critical role in certain physiological defensive responses but causes severe damage to the host organism when produced in excess. There are two forms of tumour necrosis factor, a type II membrane protein of relative molecular mass 26,000 (26K) and a soluble, 17K form generated from the cell-bound protein by proteolytic cleavage. The two forms of tumour necrosis factor and lymphotoxin-alpha (tumour necrosis factor-beta/lymphotoxin), a related protein, have similar but apparently not identical biological activities. A therapeutic agent which inhibited the release of tumour necrosis factor, but did not reduce the cell-associated activity or the level of lymphotoxin-alpha, might preserve the benefits of these cytokines while preventing tumour necrosis factor-induced damage. Here we describe a potent inhibitor of tumour necrosis factor processing and report that it protects mice from a lethal dose of endotoxin.

Development and biologic evaluation of a kit for preformed chelate technetium-99m radiolabeling of an antibody Fab fragment using a diamide dimercaptide chelating agent.

A kit has been developed for 99mTc antibody radiolabeling via defined chemistry using an N2S2 diamide dimercaptide bifunctional chelating agent and the performed chelate method. The process involved efficient transchelation of 99mTc from gluconate to 2,3,5,6-tetrafluorophenyl 4,5-bis-S-(1-ethoxyethyl) mercaptoacetamidopentanoate as an active ester ligand and subsequent conjugation to antibody lysine amine functional groups. The use of the ethoxyethyl group for sulfur protection allowed optimum yields of 99mTc N2S2 chelate formation with complete retention of the active ester. Subsequent addition of antibody Fab fragment gave 99mTc chelate conjugates indistinguishable from the stepwise in situ esterification and purification of the 99mTc N2S2 complex followed by conjugation as previously shown to give stable 99mTc antibody fragments with retained immunoreactivity and tumor-targeting properties.