FA), silica fume (SF), ground granulated blast furnace slag (GGBS), metakaolin (MK), and rice husk ash (RHA). Comparison of normal and high-strength concrete in which cement has been partially supplemented by mineral admixture has been considered. It has been concluded that mineral admixtures may be categorized into two groups: chemically active mineral admixtures and microfiller mineral admixtures. Chemically active mineral admixtures decrease workability and setting time of concrete but increase the heat of hydration and reactivity. On the other hand, microfiller mineral admixtures increase workability and setting time of concrete but decrease the heat of hydration and reactivity. In general, small particle size and higher specific surface area of mineral admixture are favourable to produce highly dense and impermeable concrete; however, they cause low workability and demand more water which may be offset by adding effective superplasticizer.This paper presents a review of the properties of fresh concrete including workability, heat of hydration, setting time, bleeding, and reactivity by using mineral admixtures fly ash ( FA), silica fume (SF), ground granulated blast furnace slag (GGBS), metakaolin (MK), and rice husk ash (RHA) which possess certain characteristics through which they influence the properties of concrete differently. The reported benefits of mineral admixtures are often associated with the harden properties of concrete; however, mineral admixtures may also influence the properties of wet concrete between the time of mixing and hardening in one or more of the following ways such as they may affect water demand, heat of hydration, setting time, bleeding, and reactivity. In the authors' view, there is no literature that summarizes the effect of these mineral admixtures on the properties of fresh concrete. Moreover, effect of mineral admixtures on the durability and on the mechanical properties of concrete remained a focus of interest. Nevertheless, effect of mineral admixtures on the properties of fresh concrete is very important as these properties may affect the durability and mechanical properties of concrete. Comparative studies have been done such as the effect of blast furnace slag and fly ash on the hydration of fresh cement paste [SF), metakaolin (MK), fly ash (FA), and ground granulated blast furnace slag (GGBS) on the setting times of high-strength concrete [FA), silica fume (SF), ground granulated blast furnace slag (GGBS), metakaolin (MK), and rice husk ash (RHA) on the fresh concrete has been reviewed.Admixtures are added in concrete to improve the quality of concrete. Mineral admixtures include fly ash  from coal is a pozzolan, which results in low-permeable and more durable concrete, which is able to resist the ingress of deleterious chemicals. This pozzolan was first reported as a controller of damaging alkali-silica reaction (ASR) in 1949 by Blanks [FA concrete are usually higher than the concrete without FA which confirms that FA plays a preventive role against ASR that is an added advantage of FA [FA concrete. These structures were inspected in 1991 after about 35–40 years of their construction. The conditional survey, petrographic examination, and damage rating index (DRI) showed no symptoms of ASR [FA [McMillan and powers were the first who used coal nditions . FA or Py Blanks . Alkaliss of ASR . In 2010GGBS was first discovered in Germany by Emil Langen; however, commercial production of lime-activated GGBS was started in 1865 in Germany [GGBS has been named in the literature as slag concrete, which is being used successfully in many countries due to accepted benefits of this material and the use of slag concrete has been recommended in their national standards [GGBS was first used with Portland cement (PC). Since then it has been used extensively in many European countries. In the UK, the first British standard for Portland blast furnace cement (PBFC) was introduced in 1923 [In 1862, SF was first obtained in Norway, during filtration of the exhaust gases from furnaces as fumes. The large portion of these fumes contained very fine powder of high percentage of silicon dioxide. Since the 1970s, filtration of gases has started at large scale and, in 1976, first standard NS 3050 was granted to use SF in factory-produced cement, extensive literature is available on SF and SF concrete [SF of 8–10% by weight of cement is added in concrete, then its effect is between 50,000 and 100,000 microspheres percent particle; that is, concrete mix will be denser and cohesive due to fine particles of SF [In 1947, MK is a processed amorphous silica material and it is obtained from calcination of kaolin to a temperature between 600 and 850°C (1112 to 1562°F) [MK in concrete has no drawbacks; however, in 1995, Martin [MK in concrete increases the compressive strength up to 110 MPa (16 ksi) with superplasticizer to overcome the higher water requirement in MK concrete. In 1996, Wild et al. [MK is 20% by weight with superplasticizer of 2.4% of binder weight. Recently, Duan et al., 2013 [GGBS, SF, and MK and it has been found that MK has positive effects on pore structure and ITZ enhancement of concrete higher than SF and GGBS [ 1562°F) ; Larbi,  1562°F) ; Halliwe 1562°F)  reported, Martin  reportedd et al.  found thRHA has high pozzolanic activity due to noncrystalline silica and high specific surface area. RHA has been used in lime pozzolan mixes for partly replacement of Portland cement [Rice husk is the outer skin of the rice grain with a high concentration of silica, generally more than 80–85% . It occud cement –27.FA is produced when coal is burnt during power generation about 1600°C (2912°F) [2), alumina (Al2O3), iron oxide (Fe2O3), and other minor constituents. According to ASTM C 618-05, there are two classes of FA based on the types of coal from which it originates. The Class F is produced by burning anthracites which is mainly a siliceous and possesses pozzolanic characteristics. The Class C contains lime and higher MgO content and it is produced by burning lignite and subbituminous coal. Class C fly ash is lighter in colour in comparison with other ashes and may cause expansion and their strength behaviour at high temperature is not apparent [2912°F) . This bu12°F . Thapparent .GGBS contains silicates and alumino-silicates of calcium and is a by-product of iron manufactured in a blast furnace. There are two techniques, granulation and pelletization, through which GGBS is produced. In granulation technique, molten slag is forced over a weir into high pressure water jets which rapidly cools the slag as granules of 5 mm (0.197 in.) diameter; however, in pelletization technique, molten slag is poured into cold water rotating drum. The fins inside the rotating drum throw molten slag in the air towards the walls of the drum where water is sprayed to cool it rapidly. This process produces particles of size 100 mm (3.94 in.) to dust, out of which particle size of less than 6 mm (0.236 in.) in size is used to manufacture the GGBS. The materials produced from these two techniques can be used as raw material for glass structured GGBS [SF is a by-product obtained after reducing high-purity quartz with coal in electric arc furnace by heating up to 2000°C (3632°F) during the production of silicon. By oxidation and condensation of exhaust gas SiO, very fine spherical particles of SF are obtained which are highly reactive with the Ca(OH)2 produced during hydration of cement [SF consists of extremely fine particles of average diameters 0.1 μm (0.00000394 in.), having pozzolanic characteristics and tendency to develop plastic shrinkage cracks [f cement . SF conse cracks , 30.MK when it is heated to the temperature between 600 and 850°C (1112 to 1562°F) [MK is a very reactive pozzolan, but its physical and chemical characteristics greatly depend on the raw material used, the temperature during calcination and finishing process  [MK with a highly disorganized structure has been produced by normal cooling as well [Kaolin is converted into  as well , 11.RHA is produced by slow burning of rice husk at a temperature between 500 and 700°C (932 to 1292°F) [RHA may produce about 20% by weight of rice husk after incineration [Rice husk is produced in millions of tons per year as a waste material in agricultural and industrial processes.  1292°F) . RHA mayneration .FA reaction with ordinary Portland cement (OPC) is a two-stage process. In the first stage, during the early curing, the primary reaction is with CaOH2; however, the reaction rate depends on the curing temperature. At room temperature, the slower CaOH2 activation minimizes the reaction rate. The effectiveness of the use of fly ash in concrete depends on many factors including the following:FA and OPC;the chemical and phase composition of 2 concentration of the reaction system;Ca(OH)FA particles;the morphology of FA and OPC;the fineness of the development of heat during the early age of hydration process;FA.the reduction in mixing water requirements with FA affect early stage properties and the rheology of concrete [FA through trial mixes by considering workability, strength development, and durability [FA and produces additional hydration products of a fine pore structure.Variations in chemical composition and reactivity of concrete . It is arability . In the The pozzolanic reaction may be represented asFA concrete as compared to ordinary Portland cement concrete; however, despite this reduction, there is sufficient lime to maintain a high pH. It is important to mention that the resulting products due to the addition of FA are different from the resultant products formed in OPC concrete. FA produces very much finer pore structure with time presuming there is reached to water to maintain the hydration process [FA [Cabrera and Plowman (1987) showed that calcium hydroxide (lime) depletes with time and its reaction affects the long-term gain of strength in  process . A pH mocess [FA .FA in which Si–O–Si link has to break to make it reactive with lime, GGBS requires to be activated to react with lime. GGBS due to its glassy structure reacts very slowly with water in the presence of activators. Commonly, sulphates and/or alkalis act as activators, reacting chemically with the GGBS. These activators disturb the glassy structure and react to increase the pH of the system up to critical. In contrast to FA, GGBS only needs a pH level less than 12 and activators. In concrete, due to hydration of cement, Ca(OH)2 is produced and acts as an activator [Unlike ctivator .SF as a pozzolan reacts with Ca(OH)2 and about 25% of SF can consume most of the Ca(OH)2 at 28 days. This is very important as the Ca(OH)2 crystals are relatively weak, brittle, and not cementitious and cracks can easily propagate through regions concentrated with Ca(OH)2 crystals, that is, the aggregate cement paste matrix interface [nterface .MK [2·2Al2O3·2H2O into SiO2·2Al2O3 [MK of amorphous phase content less than 20% can be considered as inert materials in pozzolanic activity viewpoint [MK have also influenced the activity strength index ; however, there is no increase in activity strength index by the increase of amorphous phase index above 55% [The calcination process (dehydroxylation) of kaolin is actually a transformation from crystalline to amorphous phase. The amount and type of amorphous phase influence the activity of the additives . There aMK . Dehydro2·2Al2O3 . It is a2·2Al2O3 . MK of aiewpoint . AmorphoRHA and Ca(OH)2 solution yields C–S–H gel. The morphology of C–S–H gel is like congregate, having a large specific area due to the higher porous structure. This C–S–H gel and its large specific area are the main reason improving the concrete properties with the addition of RHA [Yu et al., 1999 , found tn of RHA , 35.The physical and chemical properties of mineral admixtures and OPC have been presented in RHA and SF showing their reaction capability with the primary hydrate of cement to produce calcium silicate hydrate (CSH) which is strengthening gel in concrete; however, the content of alumina oxide is lesser in SF and RHA. On the other hand, MK has substantial contents of silica and alumina oxide showing its capability to produce calcium silicate hydrate (CSH) and calcium aluminate hydrate (CAH) which has also bonding characteristics in the concrete.The most important constituents for any mineral admixture are silica and alumina oxides. In comparison with OPC, the mineral admixtures presented in RHA, SF, and MK have the smaller particle size and greater surface area showing their capability to react more effectively with Ca(OH)2 in the concrete.The particle size and surface area are the utmost important for mineral admixtures. As reported in the literature, smaller particle size with greater surface area is favourable within concrete to be more reactive with the alkaline environment . In TablFA, GGBS, SF, MK, and RHA through field emission scanning electron microscope (FESEM) has been shown in Figures GGBS and RHA have most uneven particle size distribution even though these FESEM images are taken after grinding. Hence, it may infer that grinding procedure and duration are very important in case of GGBS and RHA. GGBS, MK, and RHA have particles of irregular shape having multiple layer structure. Whereas, the FA and SF have spherical shape particles showing a possible increase in flow ability by packing of material once used in the concrete.The microstructure of FA can be related to water demand and fineness. For a specific workability, water demand can be reduced by varying particle shape and using finer fractions of FA [FA and found that the higher strength of FA concrete depends on reducing the water content and pozzolanic performance of the cement/FA combination. It is generally believed that finer FA significantly improves strength with time [FA of 45 μm (0.0018 in.) residue > 12 percent, the water requirements are greatly reduced [FA.According to Owens, 1979 , strengtns of FA . Dewar, ns of FA , correlaith time . Monk, 1 reduced . The fluFA, less water content is required when GGBS is added. Generally, 25% to 70% of cement is replaced with GGBS in the concrete [GGBS requires about 3% lesser water content in comparison to OPC for the equal slump requirement. This is due to the smooth surface texture of the slag particles that delay the chemical reaction and increase the setting time [Similar to concrete . GGBS reSF as cement replacing by mass increased the cohesiveness of concrete and required higher water content to maintain workability; however, through vibration or pumping, SF due to spherical particles gives concrete greater flow ability as compared to ordinary concrete [SF concrete without increasing the water/binder ratio, as it is important to use SF without strength loss. As a thumb rule, one part of SF can replace 3 to 4 parts of the cement by mass without loss of strength, provided the water content remains constant [concrete . The cohconstant .MK increases the cohesiveness of concrete [SF and MK is that both mineral admixtures have high reactivity and consume water very early.concrete , 43. Theconcrete . The reaRHA has to be used; this is also due to the high specific area of finer RHA which increases the water demand. The superplasticizer content has to increase more than 2.0% for RHA having a particle size of 11.5 μm (0.00045 in.) and specific surface of 30.4 m2/g (148533.6 ft2/lb.) [The superplasticizer content needs to be increased if finer and higher percentage of ft2/lb.) .FA, SF, MK, and RHA with different water/binder ratios. Zhang and Malhotra, 1996 [RHA and SF as cement replacing material. From their experimental results, the slumps of concrete having water/binder ratio 0.4, maximum binder content 386 kg/m3 (24 lb/ft3), and 10% cement replacement have been taken [RHA of different particle size (fineness) as cement replacing material. From their experimental results, the slumps of concrete having water/binder ratio 0.53, maximum binder content 391 kg/m3 (24.4 lb/ft3), and 20% cement replacement have been used [FA and SF as cement replacing material. From their experimental results, the slumps of concrete having water/binder ratio 0.56, maximum binder content 360 kg/m3 (22.45 lb/ft3), and 10, 15, 20, 30, and 40% cement replacement with the FA or a combination of FA and SF have been plotted [SF and MK as cement replacing material. From their experimental results, the slumps of concrete having water/binder ratio 0.23, 0.3 and 0.33; maximum binder content 500 kg/m3 (31.18 lb/ft3); and 5, 10, and 15% cement replacement with SF and MK have been shown [SF and MK as cement replacing material with fixed water/binder ratio of 0.35. From their experimental results, the slumps of concrete having maximum binder content 462 kg/m3 (28.82 lb/ft3) and 5, 10, and 15% cement replacement with SF and MK have been used [In ra, 1996 , investi86 kg/m3  lb/ft3, en taken , investieen used . Nochaiyeen used , investikg/m3 22. lb/ft3,  plotted , investikg/m3 22. lb/ft3, en shown , also inkg/m3 22. lb/ft3, SF and MK is 15% maximum, whereas FA and RHA have 30% and 20% maximum replacement levels, respectively. With respect to water/binder ratio, at 5% replacement level, the maximum slump is with MK concrete having water/binder ratio 0.33 (Wong and Razak series). Similarly, the maximum slump of SF concrete is with the water/binder ratio of 0.3 (Wong and Razak series). Further increase in water/binder ratio caused reduction in slump. Moreover, MK concrete has better slump as compared to SF concrete as shown in MK concrete but with water/binder ratio 0.3 (Wong and Razak series). The maximum slump of SF concrete at this replacement level is with water/binder ratio of 0.4 . At this replacement level, FA and RHA concretes have the same slump having water/binder ratio of 0.4  and 0.56 , respectively. At 15% replacement level the maximum slump is again with MK concrete but with water/binder ratio 0.3 (Wong and Razak series). The slump of SF concrete at this replacement level is extraordinarily reduced. It is also evident from MK concrete is less affected; however, SF concrete is very susceptible with the increase in replacement level specifically from 10% to 15%. The slump of concrete having combination of FA and SF as cement replacement has also been influenced by the addition of SF and the slump is further reduced with the increase in SF content. Though increase in FA content increase the slump as shown in SF on the slump are not fully canceled by FA. From RHA caused reduction in slump (Habeeb and Fayyadh series) [SF and MK require more water content due to small particle sizes, higher specific surface area and high reactivity.From  series) . In geneFA is effective in reducing heat of hydration. The exothermic reaction during the hydration of OPC liberates energy of 500 J/g (10455.8 lb. ft./oz). Use of FA by replacing some content of cement influences temperature rise during hydration process and increases pozzolanic reaction with increasing temperature; however, the peak temperature in FA concrete is significantly lower than equivalent ordinary Portland cement concrete.According to Woolley and Conlin, 1989 , and KecFA, as the proportion of GGBS is increased, the heat of hydration is reduced. This is beneficial in large concrete pouring that enable reduced temperature rise which will reduce the probability of thermal cracking [SF by using conduction calorimetry. By increasing the content of SF, higher heat of hydration has been observed. The rate of heat liberation, expressed on a cement basis, is increased as the amount of SF increases, but the total heat liberated, expressed on a total solid basis in the mixture, somewhat is decreased as SF is substituted for cement [Similar to cracking . Cheng-ycracking , have str cement .MK mortars relative to the plain OPC mortar showing an accelerating effect of MK on OPC hydration. Note that the maximum observed temperature rise occurs at 10% replacement of OPC by MK. This temperature rise has also been confirmed by Zhang and Malhotra, 1995 [MK with Ca(OH)2 is the cause of increase in temperature.Ambroise et al., 1994 , pointedra, 1995 . The higFA and GGBS, partial replacement of cement with RHA in concrete slows down the rate of hydration in comparison with ordinary concrete. The rate of hydration remains slow during the initial three days and consequently affects the strength after 150 days [2 supply to early heat evolution, by accelerating the hydration of OPC [2 [Similar to 150 days . In genen of OPC , 57 and f OPC [2 .FA depends on ambient temperature, cement content, fineness, water content, dosages of chemical admixtures, content of FA, fineness, and chemical composition of FA [FA from 10 different sources have been conducted to estimate water requirement, setting time, and bleeding [FA. No steady water reduction was observed in Class F FA concrete. Minor increase in setting time was observed in FA concretes [The setting time of concrete in the context of on of FA . Tests obleeding . The watoncretes .GGBS slowly reacts with water as compared to Portland cement, therefore stiffening/setting time of concrete is high. The setting time will be greater at high replacement levels above 50% and at lower temperatures (below 10°C (50°F)) [SF, having a greater surface area and higher silicon dioxide content, is found to be more reactive than Pulverized fly ash (PFA) or GGBS. The high reactivity increases hydration rate of the C3S fraction of the cement in the first instance and thus decreases the setting time [Since MK are increased and are extended further with the increase in replacement level; however, by increasing the replacement level up to 15%, minor drop in initial setting time particularly is observed in comparison with 10% MK concrete [MK at the higher replacement level. With higher MK content, concrete due to higher binder phase becomes denser and results in accelerating the setting [Initial and final setting times of concrete containing 10% concrete . This mi setting ; however setting .SF concrete, the initial and final setting time of RHA concrete has been observed and initial and final setting time of RHA concrete is about 29 and 60 minutes longer than SF concrete, respectively [SF and MK concrete as compared to plain concrete. This may be due to the fact that SF and MK accelerate the hydration of cement after initial set [In comparison to ectively . Hence, tial set . In genetial set . Thus, otial set .FA showed less bleeding than plain concrete. Also, concrete with Class C FA showed lesser bleeding than concretes with Class F FA. The reduction in bleeding is due to greater surface area of particles of fly ash and lower water content with fly ash for a given workability [SF or RHA produces no bleeding water [MK as a partial replacement of cement in suitably designed concrete mixes improves cohesion and reduces bleeding of fresh concrete [Gebler and Klieger, 1986 , reportekability . On the ng water . Similarconcrete .MK is higher than the other pozzolan. The authors conducted the same test on SF and MK as shown in MK in a cement matrix eliminated the calcium hydroxide completely. Nevertheless, MK reduces the calcium hydroxide level in concrete but pH remains stable above 12.5 [Reactivity of pozzolan may be compared with the help of Chapelle test. This test is performed by the reaction of calcium hydroxide with the dilute slurry of the pozzolan at a temperature of 95°C (203°F) for 18 hours. After reaction, the consumed calcium hydroxide is determined. Largent, 1978 , reporteove 12.5 .SF and MK are chemically active mineral admixtures, whereas FA, GGBS, and RHA are microfiller mineral admixtures. Based on these two groups, the following generalized conclusions can be drawn on the properties of fresh concrete.Chemically active mineral admixtures (highly reactive pozzolan) increase the cohesiveness of concrete and require more water to maintain workability; however, the requirement of water may be offset by adding plasticizer. The water demand depends on the particle size, specific surface area, particle shape, replacement level, and reactivity of particular mineral admixture.The workability of concrete with microfiller mineral admixtures (low to moderate reactive pozzolan) greatly depends on the particle size, specific surface area, particle shape, and replacement level. In general, smaller the particle size and higher the specific surface of mineral admixture increases the water demands of concrete. The low to moderate reactivity and filler effect help to maintain the workability and sometimes increase the workability.Heat of hydration increases with the use of chemically active mineral admixtures and decreases with the use of microfiller mineral admixtures.Initial and final setting time of concrete depends on water content, initial and curing temperature, dosage of superplasticizer, and the reactivity of mineral admixture. Thus, on similar conditions, initial and final setting times of concrete decrease with the use of chemically active mineral admixtures and increase with the use of microfiller mineral admixtures.In general, setting time of concrete decreases with the increase in replacement levels of chemically active mineral admixtures and increases with the increase of microfiller mineral admixtures.All mineral admixtures studied reduce bleeding in concrete with correct proportion of all ingredients.MK > SF > FA > GGBS.Based on Chapelle test, the reactivity of mineral admixtures is of the order: Smaller particle size and higher specific surface area of mineral admixtures are favourable to produce highly dense and impermeable concrete; however, they cause low workability and more water demand which may be offset by adding effective superplasticizer.Based on the review, it is quite clear that mineral admixtures may be categorized into two groups, namely, chemically active mineral admixtures (highly reactive pozzolan) and microfiller mineral admixtures (low to moderate reactive pozzolan).


This paper examines the character of the response to HIV/AIDS in Trinidad and Tobago and assesses the impact of the response on reducing the spread of the epidemic. The launch of the National HIV/AIDS Strategic Plan in 2004 signalled the intent of the government to take the response to HIV/AIDS to a different level. This is seen by the sheer increase in the volume of resources allocated to the response from the levels of the 1980s and 1990s. The expectation was that there would be increased cohesiveness, which would allow for targeted interventions to be more effective. Though in 2009, there was a slight increase in the HIV prevalence rate to 1.5%, this was due mainly to improvements in access to antiretrovirals and same-day testing as well as improvements in data collection and analysis. The annual number of new infections fell from a high of 1709 in 2003 to 1154 in 2010. Additionally, great strides have been made in the prevention of mother-to-child transmission programme with some regions reporting 100% coverage of antenatal attendees. The study indicates that the country has responded relatively well in the areas of Strategic Planning, Care and Support, and Prevention and there has been involvement by both the public and private sector (NGOs in particular), in the response. However, there are gaps in the provision of social services and the implementing legislation to protect the rights of persons living with HIV/AIDS. Of note is the fact that a successful response to the HIV/AIDS epidemic is one that embraces all social groups, all spheres of activity and all areas of the country. In a region where the total population of the English-speaking countries is less than eight million and where some national populations are less than 100,000, the continued presence of HIV/AIDS can have a negative impact on development efforts. However, regionally there are encouraging signs that fewer people are becoming newly infected and dying from AIDS-related causes . Still, In Trinidad and Tobago, since the first diagnosis of eight cases of HIV in 1983, the cumulative number of new HIV-positive cases was reported at 22,829 by the end of 2010. Further, the number of AIDS cases and AIDS-related deaths had climbed to 6407 and 3999, respectively in 2010, based on public sector reporting . AvailabWith strong political support, active involvement of faith-based organizations, decentralized programmes and confidential voluntary counselling and testing (VCT), early successes in Uganda's fight against the epidemic influenced the structure of response programmes in other countries . TrinidaOne national AIDS coordinating authority with a broad-based multisectoral mandateOne AIDS action framework to coordinate the work of all partnersOne national monitoring and evaluation system .The government's initial response was grounded in the Ministry of Health and occurred at the time when prevention was the accepted wisdom on how to deal with the disease. Although HIV/AIDS is not solely a public health issue, the health sector's response is vital to any initiative aimed at reducing its spread, as this sector bears heavy responsibility for treatment, care and monitoring activities. It is in this regard that the configuration of the health sector – the interaction of its technical and systemic components – is critical to reducing incidence, morbidity and mortality associated with HIV/AIDS.In 1983 a National Surveillance Committee was created under the aegis of the Ministry of Health. This committee was charged with the responsibility of information gathering, surveillance, ensuring safe blood transfusion systems, and public education about HIV/AIDS itself as well as prevention methods. Meanwhile, in 1986 a Tobago AIDS Committee was formed and was succeeded in 1988 by the Tobago Hospital AIDS Committee. The main focus of this committee was the placement of patients at hospital.The National HIV/AIDS Strategic Plan (NSP) was launched in March 2004. This was the instrument for initiating the required expanded response to HIV/AIDS. Along with the launch of the NSP was the establishment of the National AIDS Coordination Committee (NACC), which had the mandate of implementing the NSP. Essentially, the NACC was created to pull together the disparate efforts of government, private sector, workplace, community, civil society and individuals. Catering to the specific needs of Tobago, the Tobago HIV/AIDS Coordinating Committee (THACC) was also established and operated under the ambit of the Tobago House of Assembly. The THACC had representation on the NACC. Due to implementation problems, the outer time bound of the NSP was extended from 2008 to 2010.Several technical and non-technical reports produced by the NACC and other agencies were reviewed and a general literature search was also conducted. Newsletters from Regional Health Authorities (RHAs) and unpublished reports from agencies involved in the fight against HIV/AIDS as well as legal documents were also perused. Additionally, discussions were held with key stakeholders located in various institutions. Most of the quantitative data were derived from technical reports of the NACC.In 1987, the National AIDS Committee (NAC) was created by the Cabinet and had the responsibility for policy formulation, programme monitoring and evaluation. The National AIDS Programme (NAP) functioned as its administrative arm. By June 1989, there were six subcommittees of the NAC, namely:Research and surveillance;Public education;Non-governmental organizations;Care and support;Legal and ethical; andTraining.The NAP carried out the policies and programmes of the various subcommittees, especially in the areas of information, education and communication. One of the major re-configurations of the NAP and NAC occurred in 1998, when the UN Theme Group on HIV/AIDS developed a proposal for the restructuring of the NAP and NAC under what became known as the National AIDS Programme Co-ordinating Unit (NAPCU). The UN Theme Group on HIV/AIDS, in facilitating UN's response to the epidemic in Trinidad and Tobago, assessed the activities of other agencies with a view to mainstreaming HIV into the country's social and economic programmes. It was also involved in resource mobilization and advocacy in the carrying out of HIV/AIDS programmes and made a key contribution in the formation of the NAPCU .In 2006 there was yet another restructuring and renaming to the HIV and AIDS Coordinating Unit (HACU), which was designed to be policy oriented. The HACU also had responsibility for funding as well as regulating, setting standards and coordinating the programmes of the five RHAs .Under the NAP, there were several initiatives. One of the main ones was Rap Port, a youth drop-in centre targeting the age group 13 – 25 years, created in response to the epidemic of HIV/AIDS/STIs affecting the youth population. The primary goal of Rap Port is ‘to promote healthy lifestyle practices among the youth by creating a supportive environment that would engender information flow, education, communication and counselling referral services’ :7. ActivIn October 2010, each drop-in centre of the Rap Port programme was re-assigned to operate under the auspice of the area RHA – Port of Spain, North West RHA; San Fernando, South-West RHA (SWRHA) and Arima, North Central Regional Health Authority (NCHR) . The proAnother important initiative, which has its beginnings in the NAP but is an independent NGO, is the National AIDS Hotline. Staffed by volunteers, this facility provides confidential and anonymous listening to persons living with HIV/AIDS (PLWHA) or persons affected by issues related to HIV/AIDS. The volunteers are carefully screened and are initially exposed to a 40-hour training programme comprising core information about the disease, basic knowledge of human behaviour, behavioural and emotional responses to the diagnosis, issues of death and dying, listening and counselling skills. Partially funded by the Ministry of Health, the Hotline is run by a board of management, and statistical data are compiled for submission to the Ministry of Health, HACU, CAREC, Joint United Nations Programme on HIV/AIDS (UNAIDS) and Pan American Health Organization (PAHO) .Through its varied health sector institutions, the state has been providing services in the areas of prevention, diagnostics, counselling, treatment and monitoring. Initially established to provide counselling and clinical care for clients presenting with STIs, the Queen's Park Counselling Centre and Clinic (QPCC&C) was subsequently given the responsibility to serve as the main referral centre for persons who were found to be HIV positive and required counselling .Concerns raised by the PLWHA community about QPCC&C indicate that breaches of confidentiality and lack of professionalism by the healthcare workers were problems. Further, the need for privacy at the Centre was also highlighted. In addition, due to its specialized character as an HIV/AIDS/STI clinic, it became a place that was largely shunned by the public. Many persons did not want to be seen at the clinic for fear of being marked with the stigma attached to the clinic.One way of addressing the stigma concerns was the integrating of the QPCC&C field services with Antenatal and Sexually Transmitted Diseases Clinics in health centres in Arima, San Fernando, Sangre Grande, Tobago, Couva, Chaguanas, Rio Claro, Princes Town and Siparia .All six secondary health institutions that are strategically located in each of the five health regions, deliver generalized palliative care and treatment for all opportunistic infections . PLWHA wWard 2 at the San Fernando General Hospital is a unit that provides specialized care for AIDS patients – an initiative spearheaded by the late Dr Edward Addo. Although the ward was closed after Dr Addo's death in 1999, the South AIDS Support, an NGO, campaigned to increase public awareness of HIV/AIDS and lobbied the South-West RHA to have the ward reopened. This was done in July 2002. The service has since expanded to include in-patient care and weekly outreach clinics in other areas of the country .The government's prevention of mother-to-child transmission (PMTCT) programme began with the first pilot in July 1999 in Tobago, while the Trinidad pilot was initiated in 2000. These pilots were a direct result of the development of a national policy for the reduction of perinatal transmission of HIV by the Ministry of Health. By 2009, approximately 96.7% of all women attending public antenatal clinics throughout Trinidad and Tobago participated in the programme . Table 1In 2008, dried blood spot testing for infants was introduced and in that year 98 infants were tested, with seven HIV-positive results. Of the 65 infants from January to September 2009, there were also seven positive results . Both thIn October 2001, the Government of Trinidad and Tobago, with assistance from UNAIDS, successfully negotiated an 85–90% reduction in the cost of antiretroviral (ARV) drugs from four leading drug companies, namely, Merck Sharpe & Dohme, GlaxoSmithKline, Boehringer-Ingelheim and Bristol-Myers Squibb . At the ARV therapy (ART) is now available free of charge at the government hospitals and at seven locations throughout the country. At the end 2009, there were an estimated 3592 patients receiving ART with the major provider being the MRF (one of the seven sites), under agreement with the MoH. Other providers include the Scarborough Regional Hospital in Tobago and the Sangre Grande Hospital. Additionally, the Eric Williams Medical Sciences Complex and the CRN were the main providers of paediatric treatment and care having 79 and 78 patients, respectively .Continuous training of the current pool of healthcare professionals is a major challenge, however, in order to maintain the service a reliable and widely available pool of trained staff will certainly be required.Rapid (same-visit) testing and VCT can be accessed at 28 sites throughout the country. Although the National HIV Testing and Counselling Policy gained approval in 2009 and was widely circulated, many persons are still not aware of their HIV status. In 2009, 295 HIV-positive cases were identified out of a total of 15,685. Of those tests that were positive, 52.5% were female and 47.5% were male .All the HIV testing in the public sector is done by the Trinidad Public Health Laboratory (TPHL). Up to the early to mid-2000s, the Caribbean Epdemiology Centre (CAREC) provided all the confirmatory testing for the TPHL. However, the TPHL currently carries out the confirmatory tests for the public sector and also provides confirmatory testing services for some private sector laboratories .The National Surveillance Unit (NSU) of the TPHL has responsibility for the surveillance of HIV/AIDS in the country. The Unit is responsible for tracking the burden of the disease, and for detecting changes in the epidemic and AIDS-related morbidity and mortality. These data are obtained mainly from the public health sector, but also include other sources such as the National Blood Transfusion Service, QPCC&C, private laboratories, private doctors, and registries of births and deaths . In ordemajor expenditure reallocation and fiscal adjustments in the name of HIV/AIDS. Expenditure in the name of HIV/AIDS remained under one million dollars annually and in 1999 amounted to TT$850,000, 16 years into the epidemic. In 2001 expenditure slightly exceeded one million (TT$1.2 million)  .In 2002, the government announced its intention to allocate TT$500 million to the fight against HIV/AIDS over the subsequent five-year period. Although there was a time lag, the NSP and the NACC were launched in March 2004. Between 2002 and 2009, there was an increase in total  expenditure from TT$25.2 million TT$98.95 million. Over the period, the total expended was TT$560 million. In 2009, the national recurrent budget for HIV was TT$39.2 million of which funding to the tune of TT$1.32 million was targeted to civil society organizations (CSOs). This was chiefly due to the increase in rapid testing facilities which grew from 5 in 2007 to 28 in 2008 . The yeaThe government's commitment to provide for the welfare of citizens has been expressed explicitly through its undertaking of wide-ranging social service programmes. In spite of this however, there is a general inadequacy of the social support system to deal with many of the social problems, some of which are directly or indirectly linked to HIV/AIDS .In addition to the National Family Services Division, which has a staff of social workers, there are also school Guidance Officers. The social worker plays a key role in prevention, through working with different community teams in the delivery of information and education programmes to the society. Institutions that are targeted include schools (children in classrooms and parent-teacher meetings), health centre clinics, NGOs and the wider community. Most social workers give voluntary service to NGOs such as the Rape Crisis Society, the Child Welfare League and CARe, a support group for PLWHA.The perception among many PLWHA is that the social services are often ad hoc and seriously under-resourced. However, in order to address the social problems comprehensively and to deal with the issues associated with HIV/AIDS, there is need for a vastly expanded cadre of social workers and counsellors.Public assistance is available to needy persons prevented by medical disability or other serious circumstance, from earning a living. Medical disability includes broken limbs and illnesses such as cardiac disease, end-stage renal failure and HIV/AIDS. Given their special nutritional and medical needs, many PLWHA who are not of independent means encounter problems meeting those needs. In addition, the need for housing in some cases as well as privacy and confidentiality when accessing the public assistance that is available make the need for reform all the more urgent. This is one challenge facing the public assistance and related-social sector agencies in Trinidad and Tobago today.Although the government's policy is that primary school education is compulsory and the constitution is intended to protect all citizens against discrimination, there have been instances of children who are HIV positive being refused admission into schools in Trinidad and Tobago. This is a violation of Article 28 of the United Nations Convention on the Rights of the Child, which the country has ratified. This ratification places an obligation on the government to address such discrimination in particular, and the overall stigmatization attached to HIV/AIDS.There have been moves by the Ministry of Education and the Ministry of Health towards incorporating a Health and Family Life Education Programme in schools. Additionally, the Adolescent Mothers Programme of the Ministry of Social Development has a component that addresses awareness and education to the target group of children with HIV/AIDS. The Draft National Plan of Action for Children also addresses issues related to HIV/AIDS.There have been three major initiatives with respect to HIV/AIDS-related legislation. sic].Employers shall not discriminate against an employee in hiring, firing and other terms and conditions of work and wages on grounds that the employee is infected with HIV and AIDS [sic], in circumstances where the information is not relevant to the type of employment offered to or performed by the employee.  (HIV) Bill was introduced in the House of Representatives on 29 October 2004. This Bill sought to amend the Offences Against the Persons Act, Chapter 11:08, in order to make it an offence to intentionally or recklessly expose another person to infection with the HIV. While there is every reason why the law should provide protection for uninfected persons, being infected with HIV should not cause any loss of equality before the law.The private health sector in Trinidad and Tobago has been a major provider of primary care health services and has emerged as a significant provider of secondary services. The sector became increasingly involved with HIV/AIDS prevention activities in private hospitals and clinics. One example is the Augustus Long Hospital, run by Petrotrin, a state-owned company. The hospital provides health education and health promotion and has a protocol in place for post-exposure prophylaxis (PEP) up to one month after exposure. A PMTCT Programme was introduced in 1998 at its antenatal clinics (ANCs) and, if found positive, mothers are offered ARV treatment for themselves and the unborn child.HIV/AIDS testing is available from three main private sector sources:at the offices or walk-in clinics of private medical practitioners who utilize the Spot or Quick Tests to obtain results;at private laboratories that conduct testing upon referral from a medical practitioner or private insurance company; andat private hospitals.It appears that unlike the situation in the public sector, private laboratories have no standard arrangements for confirmation of their screening tests. However, some do their confirmatory testing at the TPHL. This situation has serious implications for the efficiency of the national surveillance system, for when private sector data are not sent to the TPHL for confirmation, they do not enter the national surveillance network.false positive and false negative results. Second, since testing in the private sector is in a large part conducted without pre- and post-test counselling (approximately 30% provide these services), the psychological costs associated with a positive result are perhaps far greater for a private patient than for one using the public system.The current system of testing also raises several issues of equity. First, if private patients do not have the benefit of confirmation in each case, this subjects them to a greater risk of While a large percentage of the population (approximately 60%) uses the private sector for ambulatory services, private in-patient care is too expensive for the average client, unless he/she has private health insurance coverage. In cases where the client requires admission, definitive statements cannot be made about the willingness or ability of the private sector to accept HIV-positive in-patient except to say that they are dealt with on a case-by-case basis.Drugs for the treatment of opportunistic diseases related to HIV/AIDS are available through the private pharmacies when prescribed by the medical practitioner; however, private pharmacies do not routinely stock ART drugs.According to Several international agencies such as the PAHO, the International Labour Organization (ILO), the United Nations Population Fund, the UNAIDS, the European Union (EU) and the United Nations Development Programme (UNDP), among others, form part of the landscape of the social sector response to HIV/AIDS. It is of note that both PAHO and UNAIDS were actively involved with the Ministries of Health in the Caribbean region in negotiating for substantially reduced prices of ARVs in 2002. These drugs became one of the main components in the arsenal of weapons to fight the HIV virus and their availability resulted in a significant decrease in AIDS deaths as well as improved quality of life for PLWHA.The UNDP, in particular, is involved in efforts to mitigate the social, economic and human developmental repercussions of the HIV/AIDS epidemic. Its programmes place heavy emphasis on capacity building of both countries and organizations, to enable them to adequately respond to the epidemic.Similarly, UNAIDS, whose mandate is to facilitate the country's expanded response to the epidemic, played a key role in the development of several response programmes since its presence in the country from 1999 . UNAIDS The EU has been a key player in the social sector and signed a ‘Country Strategy’ with the Government of Trinidad and Tobago involving a ζ17.9 million co-operation programme for the period 2002–2007. An allocation of 80% of the resources was intended to cover the long-term development activities in the sector of tertiary education and 20% in health, more importantly for HIV/AIDS prevention. As a result of these efforts, some of the tertiary level personnel who benefitted from the programme were actively involved in crafting the strategic response, the development of the NACC as well as other initiatives.Also involved in the response to the epidemic has been the World Bank, which in 2003, approved a US$20 million loan for programmes aimed at providing treatment and care for PLWHA and reducing HIV infections. The Clinton Foundation and the United States Agency for International Development (USAID) have assisted in the area of capacity building for the clinical management of patients with HIV/AIDS.The ILO provided critical support for the development of a National Workplace Policy on HIV/AIDS . In 2007In the area of NGO participation in HIV/AIDS programmes, the need for coordination of activities is one of the main challenges. An umbrella organization, the Trinidad and Tobago HIV/AIDS Alliance, was established to address this issue. Several voluntary organizations that provide some degree of service to PLWHA are part of the alliance. They can be categorized as follows:Care and Support Groups;Faith-Based Organizations;Human Rights, Advocacy & at Risk Support Groups;Medical Community-Based Organizations;National Agencies;Reproductive Health and Rights Groups;Women's Organizations; andYouth Organizations.Some organizations keep a low profile because of homophobia and the discrimination and stigma associated with the disease. Other groups that provide various forms of support for PLWHA may not be officially recognized, nor are their efforts limited only to PLWHA. One example of this is Petals Foundation, which provides education and recreational programmes for children in the smaller care homes. Some of the organizations and services listed above operate outside of the framework of the state, whilst many are linked to the state through core financing and subventions, policy agreements and contracts. All however, must comply with the legislative and policy requirements established by government bodies. Some of the key NGO/CBO/Faith-based Organization (FBO) agencies are highlighted below.Prior to the introduction of the government's PMTCT programme, the MRF – an independent research institution headed by Professor Courtenay Bartholomew – initiated a PMTCT programme in June 1997 . WorkingThe MRF has also led to the development of the medical research programme in HIV/AIDS, conducting collaborative research studies with the National Cancer Institute and the National Institutes of Health, Maryland, USA. The Foundation was also responsible for the conducting of the HIV vaccine trials being carried out in Trinidad and Tobago.Providing emotional support to the PLWHA, CARe is a non-profit organization run by PLWHA. The organization offers professional counselling for both individuals and groups, and provides to its clients critical information on the management of HIV/AIDS, understanding medical terms, and other daily issues facing PLWHAs. The overarching goal of CARe is to empower PLWHA and improve their quality of life. Like other NGOs, CARe interacts closely with the Caribbean Regional Network of People Living with HIV/AIDS (CRN+), which was established in 1996.The PLWHA community has been very much involved in the response to HIV/AIDS, in the face of extreme odds. In June 2004, the CRN+ was awarded US$3 million in grant funding from the Global Fund to continue its work in the region and build the institutional capacity of local networks such as CARe.Established in November 2000, the Tobago Oasis Foundation provides services to PLWHA. The aim of the Foundation is to promote the welfare and dignity of persons with HIV/AIDS. This is done through a range of programmes involving treatment and care, prevention, health, education and spirituality, with a full awareness of the cultural traditions of the people. Some of the programmes include outreach to PLWHA and their families, working against stigma and discrimination, as well as fostering regional and international networking.This Society was founded in 1996 and has as one of its main objectives, assisting PLWHAs with the purchasing of drugs for the opportunistic diseases that result from HIV/AIDS. The Society also helps PLWHAs and their families with financial assistance for housing when they become homeless, and also gives support for school fees, uniforms, books and food to children whose parents are living with HIV, who may themselves be living with HIV or who are orphans. Home care is also provided for those who are ill.culturebase.netThe role of culture in the communication of health messages is critical. The Grassroots group such as Arts in Action has been involved in health education and promotion workshops for children aged 6 – 12 years, teenagers at secondary school and youth and adults in tertiary education, in the workplace and in communities . EstabliThe Toco Foundation, located in the north-east region of Trinidad, is a grassroots community enterprise that has achieved astounding success in its short existence. Established in 1994, the Foundation's activities are separated into three distinct units to streamline operations and make service delivery more efficient. The units are Communications, Social Services and Agro-Tourism.With the possible exception of Radio Toco, the Toco Youth Sexuality Project (TYSP), run by the Social Services Unit, is perhaps the most well known of the projects undertaken by the Toco Foundation. This project was awarded the Commonwealth Award, first place, for Youth and HIV/AIDS, 2002. The TYSP works with two thrusts. The in-school unit visits schools along the coast from Matura to Matelot, a distance of 38 miles (and goes to other counties if requested). The out-of-school arm visits prenatal and post-natal clinics, youth groups, village councils, church groups and popular liming spots; it also does house-to-house education. Both arms deliver a powerful message on all the issues surrounding HIV/AIDS, sexuality and STIs, establishing the facts and clearing up the myths that exist. They also cover topics like negotiation skills, nutrition and hygiene. These visits make use of dramatic presentations, role-playing techniques, interactive talks and condom demonstrations to deliver the message to the audiences.Presentations are also made via Radio Toco. On these programmes presentations are arranged thematically and the issues that are presented during the face-to-face sessions are covered in great depth; time is devoted to listeners who either call in or mail in their questions. From time to time, a forum is also given to presenters outside the TYSP who do work in the field to discuss their efforts and to answer questions.The CRN, a residential operated by the Society of St. Vincent De Paul, was opened in September 1994. It is the major FBO involved in the treatment and care of PLWHA. The Nursery cares for children with HIV/AIDS and is the first and only facility in the country to specialize in caring for children living with the virus. As its name suggests, it was originally intended for very young children, since prognosis for the disease at that time indicated such a shortened life span, that children were not expected to survive much beyond early childhood. The facility was originally designed to cater for 25 children, but has 35 children in its care, ranging from 1 to 18 years of age.Children are referred to the Nursery by Medical Social Workers who are in constant contact with hospitals, where babies born with HIV are sometimes abandoned by their parents. Children whose parents have died from AIDS and those whose parents are unable to provide adequate care for them are also admitted to the Nursery. The Nursery gets a subvention each year from the Ministry of Social Development and has also been a recipient of a number of grants from the NACC.The Nursery has a school within its compound that caters to the educational needs of the younger children. Most of the older children attend St. Mary's Anglican Primary School. A doctor provides his services free of charge and pays regular visits to the Nursery. The children also receive paediatric care at the Eric Williams Medical Sciences Complex. There is no social worker at the Nursery and social work services have been provided through the placement of students from the Social Work Unit of the University of the West Indies.This model can be duplicated in communities throughout Trinidad and Tobago, with NGOs providing the emotional and physical support needed by children living with HIV. However, it must be noted that homes like these were initially meant to be temporary, with the aim of reintroducing the children into their families and communities. To the extent that this aim is not accomplished, there is need to ensure that children will be cared for in familiar surroundings, attend district schools and churches and take part in local recreational activities, so that communities can become involved in their development.A National Policy on HIV/AIDS in the Workplace had its genesis in a National Consultation on HIV/AIDS in 1992 and benefited from dialogue among a varied cross-section of the society – business professionals, health experts, NGO representatives and the AIDS Programme Co-ordinator . The WorAdditionally, a post-exposure policy for healthcare workers has existed since 2000. The policy involves protocols for the use of ART, rapid HIV laboratory testing and counselling.The trade union movement has been relatively low-keyed in its response. A representative from one of the leading trade unions indicated that the union had participated in seminars where discussions were held on HIV/AIDS in the workplace, but had not on its own, initiated programmes for its membership. According to the Situation and Response Analysis of HIV/AIDS in Trinidad, 2001:Three areas were identified under which issues around HIV/AIDS can be addressed. These were through Occupational Health and Safety (OHS) programmes, Employees Assistance Programmes (EAP) and programmes geared to promote healthy lifestyles. It was felt that of the three, either the EAP or general wellness programme was better placed to address the issue of HIV/AIDS. It was not clear however, that the latter was as widely implemented as the former. The focus of the OHS programme has tended historically to focus on the areas around accidents and safety and less on general health components. (HEU 2001:64)The trade union movement has begun making small steps towards dealing with the issue of HIV/AIDS. One of the reasons put forward for the past lack of commitment is that persons have not come forward stating that they have been discriminated against in the workplace as a result of their positive HIV/AIDS status. Union officials indicated that it is difficult for trade unions to accomplish change in organizational policies unless they have the openings of negotiating collective agreements. It is common practice now that in every new agreement negotiated by the union, a clause is inserted against discrimination against PLWHA.Another large union, the Public Services Association (PSA), commissioned all its members with direct links to PLWHA and whose work entails dealing ‘hands on’ with HIV/AIDS – nurses, mental health workers, etc. – to formulate an internal policy for the Association. The union also provides monthly financial support to the South AIDS Support (SAS), which is a PLWHA support group. The SAS, in turn, does sensitization lectures for PSA members.Insurance companies offer no services to persons known to be PLWHA, even though they may be long-standing customers. Often, the HIV test is done on clients submitting to medical tests for insurance without their knowledge and with no prior counselling.given to insurance companies that do not discriminate against PLWHA. Further, in the face of reduced costs for, and improved access to, treatment for HIV/AIDS, as well as increased longevity associated with early treatment, insurance companies are presented with alternatives for coverage of PLWHA.In assessing the impact of the response, the status of the epidemic points to some measure of success, especially in the area of treatment. The data indicate that there has been a small but continuous increase in HIV prevalence rates from 1.2% to 1.5% between 2006 and 2009 . With thThe number of new infections reached a high of 1709 in 2003  but has The PMTCT programme is one of the more successful prevention strategies. An increasing number of antenatal clinic attendees are tested nationwide and in both Tobago and the county of Caroni-North, there has been the achievement of 100% testing of clinic attendees. Despite challenges such as inadequate follow up of mothers and babies, access to all babies who need to be tested and lack of testing of partners and other children, the programme has had a positive impact on reducing the transmission rates from mothers to their children.It would also be useful to contextualize the response based on the Millennium Development Goal indicators and those of , 2004b tSince HIV/AIDS affects all levels of humanity, whether as individuals, families, communities and countries, in our increasingly interdependent world, no class is immune from this epidemic. The NSP, which provides the blueprint for the coordinating function details in large measure, this very interconnectedness and the roles of the various agencies. within each county. These national groups have contributed greatly to the response, and their efforts should continue unabated.Although countries look to international experience to help in fashioning their response, the nature of the epidemic demands that actions be taken by the individuals, organizations, groups and communities From the experience of other countries, we may identify the ingredients for a successful response as follows:(1)Clear understanding by the community and the leaders of the nature of the phenomenon. This presumes that there is ample evidence/research, and that there is an effective machinery for disseminating information.(2)Appropriate technical inputs. This includes the identification of proper instruments and resource requirements, inclusive of existing agencies or institutions and policies/programmes.(3)A general commitment to initiate and sustain the response on a personal, social or community and political level. The needed adjustments in time and resources will depend on this commitment.Given the reality of objectively determined obstacles to the response, including a shortage of trained personnel in many areas and information systems in need of modernization, it becomes even more important that in Trinidad and Tobago, a conscious effort be made to speed up the implementation of measures to continue the fight against the spread of HIV/AIDS.


Hyper-IgG4 disease is a rare systemic disorder that usually affects middle age males. It is characterized by elevated serum IgG4 levels and infiltration of organs by IgG4 positive plasma cells associated with fibrosis. Patients usually present with mass or masses in the involved organ that mimic neoplasia. While initially described in the pancreas, IgG4-related inflammatory tumors have been now described in many organs. We describe an unusual case of an IgG4-related pseudotumor of the kidney. Hyper-IgG4 disease is one of the recently recognized systemic autoimmune disorders in which there is a patchy or diffuse infiltration of the organs with IgG4 positive plasma cells along with fibrosis. It tends to occur in middle-aged men. The pancreas is the most common organ that has been reported to be involved. These patients usually present with obstructive jaundice, a pancreatic mass or chronic pancreatitis. Individuals with hyper-IgG4 disease may have involvement of many different organs and even present with lymphadenopathy . The mosThe patient was a 71-year-old female with past history of pancreatoduodenectomy (Whipple) performed at an outside hospital for a pancreatic mass eleven years prior to the current report. A diagnosis of benign inflammatory pancreatic mass of undetermined etiology was made. She presented at our institution for evaluation of hypertension; her serum creatinine was within normal range at 0.56 mg/dL (0.4–0.9 mg/dL). Computed tomography showed a 2.5 cm, circumscribed, enhancing mass in the right mid kidney near the hilar. This mass was presumed to represent a renal carcinoma and a nephrectomy was performed. Gross examination revealed a well-circumscribed 3.5 cm firm white homogenous mass that was confined to the kidney . No hemoHyper-IgG4 disease or IgG4-related systemic disease is a recently described disease. It was first described by Kamisawa et al.  in 2003 The main characteristic features of this disease are the elevation of serum IgG4 and/or infiltration of different organ by IgG4 positive plasma cell along with tissue fibrosis and obliterative phlebitis. Over the past few years, the diagnostic criteria and the necessity to have tissue biopsy to confirm the diagnosis of IgG4-related pancreatitis have been debated . The intAlthough the pancreas is the most common reported organ to be involved, many patients with IgG4-related disease without pancreatic involvement have been reported , 8. HypeThe kidneys are not spared in IgG4-related system disease , 10. MosMost reported IgG4 kidney patients have been diagnosed with serologic studies showing a marked elevation of IgG4 and supportive radiographic imaging. Nephrectomy in these patients is uncommon and our knowledge of the gross findings of these lesions is limited. At gross examination, we found a firm, homogeneous white mass that was not associated with necrosis or hemorrhage; findings similar to those reported by Shoji et al. . The sizThe main pathologic finding in IgG4-related pseudotumor of the kidney includes a patchy or diffuse tubulointerstitial nephritis associated with storiform fibrosis . The infThere is no international consensus on the histopathologic diagnostic criteria for IgG4 disease of the kidney. Kawano et al. proposed diagnostic criteria for IgG4 kidney, disease that include serology, imaging, kidney function tests and histology. Two histologic criteria were proposed: (1) the presence of dense lymphoplasmacytic infiltration with more than ten IgG4 positive plasma cells/high-power field (HPF) and/or a ratio of IgG4+ to IgG+ plasma cells greater than 0.4; (2) characteristic fibrosis surrounding nests of lymphocytes and/or plasma cells. According to these criteria, tissue evaluation  was not necessary to render the diagnosis given the appropriate clinical criteria.N-acetyl-β-D-glucosaminidase, β2-microglobulin, and/or α1-microglobulin excretions in urinalysis) with characteristic radiologic findings with with either elevated serum IgG level, hypocomplementemia, or elevated serum IgE level. An algorithmic approach has been suggested by Kawano et al.  in whichThe current treatment of choice for IgG4-related disease is corticosteroids. In the few case reports and case series of renal involvement by IgG4 disease, the renal masses have been shown to decrease in size on therapy, with some disappearing and others recurring after cessation of therapy , 12. In In our patient, no preoperative biopsy was performed because the radiologic findings were felt to be consistent with a renal cell carcinoma . Nephrectomy was the only treatment she received because her renal function was normal and there was no evidence of IgG4 disease of the left kidney or other organs. This case highlights the importance of recognizing that IgG4-related diseases may involve the kidney and result in masses that can simulate a primary renal malignancy.


POSS-PCU has already been used in 3 first-in-man studies, as abypass graft, lacrimal duct and a bioartificial trachea. We therefore postulate that itssuperior biocompatibility and unique biophysical properties would render it an idealcandidate for coating medical devices, with stents as a prime example. Taken together,anti-CD34 functionalized POSS-PCU could form the basis of a nano-inspired polymer platformfor the next generation stent coatings.An unmet need exists for the development of next-generation multifunctional nanocompositematerials for biomedical applications, particularly in the field of cardiovascularregenerative biology. Herein, we describe the preparation and characterization of a novelpolyhedral oligomeric silsesquioxane poly(carbonate-urea) urethane (POSS-PCU)nanocomposite polymer with covalently attached anti-CD34 antibodies to enhance capture ofcirculating endothelial progenitor cells (EPC). This material may be used as a new coatingfor bare metal stents used after balloon angioplasty to improve re-endothelialization.Biophysical characterization techniques were used to assess POSS-PCU and its subsequentfunctionalization with anti-CD34 antibodies. Results indicated successful covalentattachment of anti-CD34 antibodies on the surface of POSS-PCU leading to an increasedpropensity for EPC capture, whilst maintaining  Cardiovascular disease is the number one cause of death in the world, and it is estimatedthat by 2030, 23 million people will succumb annually to cardiovascular-related diseases. AtherosTo this end, we have developed a proprietary nanocomposite polymer, polyhedral oligomericsilsesquioxane poly (carbonate-urea) urethane (POSS-PCU) for medical applications. POSS-PCUis a novel nanocomposite polymer, capable of functioning as a component of artificial organs, coatingPOSS® was initially developed by the United States Air Force as a new breed of material foraerospace engineering purposes , 12. WitWe therefore postulated that coating BMS with the highly biocompatible nanocompositepolymer, POSS-PCU, would prevent ISR. Furthermore, functionalizing POSS-PCU with endothelialprogenitor cell (EPC)-specific antibodies, (i.e. anti-CD34 antibodies), could attractcirculating EPC and thereby enhance endothelialization to prevent late ST Figure . Althouginvitro biocompatibility; atomic force microscopy (AFM) was used to visuallycharacterize surface topography and quantify surface roughness; Raman spectroscopy and Ramanintegration maps were used to identify POSS regions, PCU regions, and antibody regions ofthe polymer; X-ray photoelectron spectroscopy (XPS) was used to measure and quantify surfaceelemental composition; EPCs were cultured onto POSS-PCU films to assess the efficacy of EPCcapture; POSS-PCU-coated stents were placed in a flow circuit mimicking physiological flowconditions to assess the stability of antibody immobilization.This study attempted to assess the feasibility of using POSS-PCU as a polymer coating forcoronary stents, as well as its potential for being an endothelial progenitor cell (EPC)capture platform, when functionalized with anti-CD34 antibodies. Fourier transform infraredspectroscopy was used to detect chemical groups in POSS-PCU films; water contact angle wasused to measure surface wettability; quantum dots (QDs) tethered to secondary antibodieswere used as fluorophores to detect primary antibodies on POSS-PCU, thromboelastography(TEG) was used to assess hemocompatibility; Alamar Blue was used to assess Therefore, the aim of this study was to use biophysical techniques to assess the surfacemodifications of POSS-PCU after antibody attachment, and also to assess the feasibility ofusing POSS-PCU-CD34 as an EPC capture platform for stent coatings.All reagents were purchased from Sigma Aldrich UK, unless otherwise stated. For proceduresthat involved the use of human blood and tissue, informed consent was obtained from healthyvolunteers, and the Institutional Review Board (IRB) at the Division of Surgery &Interventional Science at University College London approved the study protocol. Allexperimental procedures were done in triplicates (n = 3) unless otherwise stated.Synthesis of POSS-PCU for peptide functionalization has been previously describedelsewhere . Briefly3, pH = 9) were added onto the different test samples. Themixture was transferred to a 96-well plate and left to stand for 2 hours. Thereafter,34 μl of OPA (10 mg/ml in ethanol) was added. The plate was placed in a Fluoroskan AscentFL microplate fluorometer/luminometer (Thermo Scientific). A 360 nm excitation filter, anda 460 nm emission filter were selected.OPA assay was used to detect the presence of primary amines on POSS-PCU that would befunctionalized with antibodies. 83 μl of 2-mercaptoethanol and 833 μl of borate buffer was added to 2 g of POSS-PCU.The parameters used for the polymer coating were written into the program of the MediCoatDES 1000 Ultrasonic Spray System (Sono-Tek Corporation USA). Polymer solutions were fedinto the nozzle, through a syringe, of the ultrasonic atomization spray system. Nitrogengas  pressure was set at 4.5 PSI. Ultrasonic power was set to0.24 W. Rate of syringe injection was set at 0.1 ml/min. Translational movement of mandrelwas set at 2.5 mm/sec, and rotational movement was set at 115 rpm.Platinum chromium intra-arterial stents (Boston Scientific USA) with diameters of 3.5 mmand lengths of 20 mm were placed on mandrels, in such a way that half of the stent length“overhangs” out from the mandrel, enabling it to be spray coated in both the luminal andabluminal area while the mandrel rotates. Drying gas was utilized during this procedure at1.0 PSI. The half-coated stent was then placed in a drying oven (Binder GmbH) at 65°C for3 hours to allow for solvent evaporation. The coating process was repeated for the otherhalf of the stent.Polymer films (for cell culture) were also fabricated a similar manner, and the rotatingmandrel was spray coated with the polymer using identical parameters mentioned above. Avertical incision was made lengthwise on the coated mandrel, and the polymer films werecarefully peeled off.N-(3-Dimethylaminopropyl)-N’-ethylcarbodiimidehydrochloride (EDC), 0.0115 g of N-hydroxysuccinimide (NHS), and 0.05 gof succinic acid were placed in a 50 ml conical tube. To this, 20 ml of phosphate-bufferedsolution (PBS) was added. The mixture was placed on a roller mixer (Stuart Equipment) for3 hours, to allow activation.The protocol for covalent bonding of peptide motifs on POSS-PCU was previously developedby de Mel in our lab, and in-depth discussion can be found elsewhere . BrieflyCircular-cut discs of polymer sheets were placed in a 24-well plate. 500 μl of theabove-mentioned EDC-NHS-PBS mixture was pipetted onto each polymer sheet in the wells. Thewell plate was wrapped in aluminium foil to avoid light, and placed on a Luckham R100Rotatest Shaker (Richmond Scientific Ltd.) for 3 hours.500 μl of PBS, and 5 μl of mouse anti-CD34 concentrate (2 μg/ml) (Life Technologies) werepipetted into an eppendorf tube. Equal amounts of the antibody solution were pipetted into24-well plates. The well plate was wrapped in aluminium foil and placed on a shaker for30 minutes. It was then transferred to a 4°C fridge and left for 24 hours. After 24 hours,the polymer discs were washed with PBS.POSS-PCU-coated stents were also covalently-bonded to anti-CD34 antibodies, using asimilar protocol as mentioned above.-1resolution, with a wavenumber range of 600 cm-1 to 4000 cm-1.Chemical groups were detected using ATR-FTIR with a Jasco FT/IR 4200 spectrometer . Parameters were set at 20 scans at a 4 cmRaman and AFM scanning were performed using NT-MDT NTEGRA Spectra® system with an uprightRaman microscope and a universal head. AFM scanning was done in semi-contact mode withcommercial rounded cantilevers for large scans, purchased from MicroMasch . Raman scanning was done in backscattering geometry with a Mitutoyolong-working distance objective . The excitation source was a 473 nmsolid-state Cobolt Blues® laser with power at the sample being 2 mW. Acquisition time perstep was 10s and step size was 0.5 microns. Optical images of the area were captured usingthe same objective.A KRÜSS DSA 100 (KRÜSS GmbH) system was used for static water contact angle measurement,using a sessile drop method. Sterile deionized water was used as a solvent, with dropletvolume of 3 μl. A highly hydrophobic material, Teflon® (DuPont USA) and a highlyhydrophilic material, Acuvue® (Johnson & Johnson) served as controls.The effect of polymer material on blood coagulation kinetics was assessed using a TEG®5000 Thromboelastograph® Hemostasis Analyzer System (Haemonetics Corporation USA).Cuvettes were spray coated with POSS-PCU and further conjugated with anti-CD34 antibodiesin the protocol mentioned above. Uncoated cuvettes served as controls. Whole blood wasobtained from healthy volunteers and 320 μl of whole blood were pipetted into eachcuvette.Samples were mounted on an aluminium stub and sputter-coated with gold via vapourdeposition using SC500 (EM Scope), and imaged using a Philips 501 SEM .The analysis of the samples was carried out using a Thermo Scientific Theta Probe XPSrecently calibrated in November 2012. Monochromatic Al Kα X-ray (hν = 1486.6 eV) wasemployed with an incident angle of 30° with respect to surface normal. Photoelectrons werecollected at a take-off angle of 50° with respect to surface normal. The analysis area wasapproximately 400 μm in diameter while the maximum analysis depth lies in the range of 4 -10 nm. Survey spectra and high-resolution spectra were acquired for surface elementalidentification and for chemical state identification, respectively. For chemical stateanalysis, a spectral deconvolution was performed by a curve-fitting procedure based on aLorentzian function, and broadened by a Gaussian function.Two cell lines were selected for this study: endothelial progenitor cells (EPCs) andhuman umbilical vein endothelial cells (HUVECs). EPCs were selected as we wanted to findout the capturing efficacy of CD34-POSS-PCU, while HUVECs were used to confirm thatCD34-POSS-PCU were able to support the growth and proliferation of endothelial cells. Bothcell lines were cultured in the same type of cell culture medium to ensure experimentalconsistency.g for 10 minutes. Thesupernatant was discarded and the pellet re-suspended in 5 ml HBSS and mixed gently. Thiscentrifugation and supernatant-discarding process was repeated 2 more times. The cellswere then re-suspended in 5 ml cell culture medium M199 (Life Technologies) with 10% FBS(Life Technologies), and 1% penicillin and streptavidin (Life Technologies). Cells werecounted using Trypan blue exclusion dye, using 10 μl Trypan blue, and 10 μl cellsuspension. Cells were seeded at a density of 1.0 × 106 cells per well in a24-well plate. It was then incubated at 37°C with 5% CO2 for 21 days. Culturemedium was replenished every 3 days, and cells were examined under light microscopy every3 days.Details of EPC extraction were reported previously by our group , 26. Who6 cells per well in a 24-well plate. It was then incubated at 37°Cwith 5% CO2 for 21 days. Culture medium was replenished every 3 days, and cellswere visualized every 3 days.HUVEC extraction was described extensively by our group in a previous report , 28. TheAlamarBlue® (Life Technologies) was added to the cell culture medium at a volume tovolume concentration of 10%. After 7 days, culture plates were washed with PBS and 1 mlwas added to each well. 100 μl was aspirated after 4 hours. Fluorescence was measuredusing a Fluoroskan Ascent FL microplate fluorometer/luminometer (Thermo Scientific). A360 nm excitation filter, and a 460 nm emission filter were selected.6) were usedin the flow circuit. Viscosity was approximated to that of blood, by adding 8% lowmolecular weight Dextran (77000 Da). Anti-CD34 POSS-PCU coated-stents, POSS-PCU-coatedstents, POSS-PCU films, anti-CD34 POSS-PCU films, and IgG-POSS-PCU films were placed in amicrotubule and subject to physiological flow conditions for 28 days.A home-built flow circuit was used to mimic physiological flow conditions in the humanbody. An electromagnetic pump and a variable height fluid reservoir maintained pressure ataround 120 mmHg / 80 mmHg, and “heart beat” at 84 beats per minute. An ultrasound Dopplerprobe was used to monitor and maintain flow conditions using a Light Patient Monitor(Datex Engstrom). Culture medium with peripheral blood cells (1× 10x solution (where x denotes the type of antibodyused) was added to the mixture and mixed for 1 hour at room temperature. To separate thereagent and unconjugated CdCoTe/MSA/ QDs, 100 kDa Amicon® Ultra-centrifugal filters(Millipore Corporation) with UV monitoring at 280 nm of the retained samples was used. Thepurified samples were collected and stored at 4°C until further use. The sample wasfurther characterized by NIR fluorescence and FTIR spectroscopy.Quantum dots (QDs) were manufactured in-house by our lab in a study described previously, and mod2) and greenQD –Ab (CD34) to each well and incubated for 2 hours in the dark at 4°C. Cells were thenvisualized and counted. Samples were washed with PBS-Tween 20 to remove unwanted QDs.300 μl of diluted DAPI was added to each well and incubated for 5 minutes. They were thenwashed with PBS-Tween 20.Cells were fixed with 2% formaldehyde (PFA) using the following method. Briefly, cellswere washed twice with 0.1% PBS-Tween 20 at room temperature. They were then treated with2% PFA for 20 minutes, and washed 3 times with 0.1% PBS-Tween 20 for 5 minutes per wash.Cells were permeabilized with 0.5% PBS-Tween 20 for 15 minutes. They were then furtherwashed 3 times with 0.1% PBS-Tween 20 for 5 minutes per wash. Cells were blocked andincubated with quantum dots using the following methods. PBS-Tween 20 was removed. Cellswere blocked with 500 μl of 1% BSA (in PBS-Tween 20) for 20 minutes at 4°C, and thenwashed with PBS-Tween 20. 500 μl of 0.25 μg/ml of red QD-Ab (VEGFRImages were acquired by a fluorescent microscopy unit (Nikon Eclipse TE 300). The PCMscanning head was mounted on an inverted optical microscope (Nikon Eclipse TE 300), whichcan operate in fluorescence, reflection and phase contrast modes, and it was fitted with aPlan Fluor dry objective (20×/NA = 0.5). Lasers at 488 nm and 543 nm were the sources,housed in a common module, providing the excitation beams that were delivered to thescanning head through a single-mode optical fiber. Photomultiplier (PMT) tubes were placedwithin the control unit, and the collected light arrived via high-transmission opticalfibers.t-test. p-values ofless than 0.05 were considered statistically significant.Curve fitting (least squares method) and statistical analyses were conducted at 95%confidence interval using MATLAB® (MathWorks Inc.). Statistical significance testing wasconducted using unpaired Student’s The OPA assay revealed a higher fluorescence signals from POSS-PCU-CD34 compared toPOSS-PCU Figure . This in-1 represents the Si-OR functional group in the POSSmolecule, as POSS has a chemical formula of (RSiO1.5)n and symmetric (1340 and 1464 cm-1) Si-C-H bending vibrations.The Si-O vibrations are clearly discernible from the spectrum, which results after thesubtraction of the PCU-rich domain spectrum from a POSS-rich one Figure C. Most pThe POSS-PCU-CD34 and POSS-PCU-CD34-QD samples did not show any significant differencesin their Raman spectra, however the former appeared to degrade faster under laser beamthan the control sample (POSS-PCU). This was not observed (or at least to a much lesserextent) with the latter sample (CD34-QD). There was a minimal gain, if any, of theintensity of those bands in the QD sample.-1 and result in an integration map with higher contrast.Raman AFM images also showed a cobblestone-like appearance, in agreement with opticalimages. Phase AFM images also showed the stiffness variability on the surface, and had asimilar pattern to Raman AFM and optical scans. Antibody-QDs were also mapped using Ramanaccording to their characteristic peaks  than that in POSS-PCU (0.5%) suggests successful graftingof antibody on the surface of POSS-PCU. Na and Cl were likely to be present as NaCl, whichwere present in the anti-CD34 concentrate. Literature has shown that XPS is a viabletechnique for detecting the attachment of antibodies on surfaces .Water contact angle measures the hydrophobicity/hydrophilicity of a material. POSS-PCUdisplayed a contact angle of 100.3° (± 2.7) suggesting a certain degree of hydrophobicity minutes; POSS-PCU coatedcups had an r-time of 14.36 (± 2.6) minutes; CD34-POSS-PCU coated cupshad an r-time of 16.57 (± 1.9) minutes. Tests were not statisticallysignificant from control (p > 0.05). k-time measuresthe speed at which the clot forms a size of 20 mm. Uncoated TEG cups had ak-time of 7.55 (± 1.0) minutes; POSS-PCU coated cups had ak-time of 6.9 (± 1.2) minutes; CD34-POSS-PCU had ak-time of 8.4 (± 1.4) minutes. Tests were not statistically significantfrom control (p > 0.05). Maximum amplitude (MA) is the width of thecurve at the widest point, and gives information about clot strength. Uncoated TEG cupshad an MA of 51.56 (± 3.1) mm; POSS-PCU coated cups had an MA of 49.67 (± 2.6) mm;CD34-POSS-PCU had an MA of 52.59 (± 3.5) mm. Tests were not statistically significant fromcontrol (p > 0.05). α-angle measures the rate of increase of elasticshear modulus. Uncoated TEG cups had an α-angle of 35.9° (± 2.3); POSS-PCU coated cups hadan α-angle of 33.2° (± 1.8); CD34-POSS-PCU coated cups had an α-angle of 31.7° (±2.5).Tests were not statistically significant from control (p > 0.05).These results collectively indicated that, as POSS-PCU and CD34-POSS-PCU coated cups didnot deviate significantly from uncoated TEG cups, therefore they had a negligible effecton coagulation kinetics, indicating high a degree of hemocompatibility.The TEG results revealed that POSS-PCU-coated TEG cups did not deviate significantly fromcontrol, suggesting that POSS-PCU did not adversely affect clotting kinetics of humanblood Figure . CD34-POTEG measures the coagulation kinetics of blood in real-time, and is used in cardiac andtransplant surgery to assess if patients have a clotting disorder. Therefore, we wanted toassess the suitability of POSS-PCU as a blood-contacting interface, testing it against theindustry-standard TEG cuvettes. Results of POSS-PCU and CD34-POSS-PCU did not deviatesignificantly from uncoated cups, indicating that they did not adversely interfere withnormal clotting kinetics.Endothelial progenitor cells were shown to adhere and differentiate on CD34-POSS-PCUpolymer films. In contrast, pure POSS-PCU films, and non-specific IgG-POSS-PCU films didnot show any EPC capture. Results indicated that only CD34-POSS-PCU were able to captureEPCs, and also to serve as a platform on which growth and proliferation were maintainedFigures  and 13. The AlamarBlue® assay was conducted to assess biocompatiblity, and it was shown thatcells attached to both POSS-PCU and CD34-POSS-PCU demonstrated a favourable level ofnormalized metabolic activity, similar to that of positive controls Figure . Cells gTherefore, results indicate that both pure POSS-PCU and POSS-PCU-CD34 were able tosupport the growth and proliferation of EPCs and HUVECs, with a level similar to positivecontrol.To evaluate the robustness and stability of the covalently-linked antibody on POSS-PCUsurfaces, antibody-POSS-PCU-coated stents were placed in a custom-built flow circuit tomimic physiological flow conditions in human arteries Figure . Stents The concept of EPC capture for accelerated endothelialization represents a novel method forrestoring vessel physiology in the field of regenerative medicine. This study has sought toassess the feasibility of functionalizing a POSS-PCU nanocomposite polymer with anendothelial progenitor cell-specific antibody. We selected anti-CD34 antibodies as we hadconducted preliminary work with other EPC-specific antibodies, including anti-CD133 and vWF,and found the capturing efficacy was not as potent as anti-CD34. Furthermore, anti-CD34antibodies are currently used commercially in an endothelial progenitor cell capturingstent, Genous™ Stent . Howeverinvitro rather than in vivo. Furthermore, it has been previouslyshown that the levels of circulating EPCs in peripheral blood are extremely low (<0.002%)[2O2/CoCl2 system); mechanical engineering aspects of POSS-PCU toshow robust integration and bonding to metal struts without cracks or fractures; invivo biostability of the entire system in an animal model.We recognize that a limitation of this study is that it is conducted <0.002%), and the<0.002%). HoweverAn ideal nanocomposite polymer material for coating stents for cardiovascular purposesshould be highly biocompatible, haemocompatible, and also non-biodegradable to preventparticles and by-products from leaching into biological systems. We have previouslydemonstrated POSS-PCU to be suitable for biomedical applications, and ideal for use asvarious cardiovascular devices such as cardiac valves  and vascOther studies have proposed the use of antibody-functionalized polymer platforms, such aspolyethylene glycol (PEG) , polylacTaken together, we have demonstrated a proof-of concept that anti-CD34antibody-functionalized POSS-PCU nanocomposite polymer can serve as a platform on which tosupport the growth and proliferation of EPCs with the aim of achieving a confluent layer ofendothelium to mimic native vessel physiology.


We assessed health-related quality of life (HRQOL), its associated factors, and examined measurement properties of the EuroQol - 5 Dimensions - 5 Levels (EQ-5D-5L) in HIV/AIDS patients.A cross-sectional multi-site survey was conducted in 1016 patients  in three epicenters of Vietnam. Internal consistency reliability, convergent validity, and discriminative validity of the EQ-5D-5L and a visual analogue scale (VAS) were evaluated. Tobit censored regression models were used to identify predictors of HRQOL in HIV/AIDS patients.The mean EQ-5D-5L single index and VAS were 0.65  = 0.63; 0.67) and 70.3 . Cronbach’s alpha of five dimensions was 0.85. EQ-5D-5L has a good convergent validity with VAS (0.73). It discriminated patients at different HIV/AIDS stages, duration of ART, and CD4 cell count. Predictors of poorer HRQOL included being female, lower education level, unemployment, alcohol and drug use, CD4<200 cells/mL, and advanced HIV/AIDS stages.The EQ-5D-5L has good measurement properties in HIV/AIDS patients and holds potentials for monitoring ART outcomes. Integration of HRQOL measurement using EQ-5D-5L in HIV/AIDS clinical practice could be helpful for economic evaluation of HIV/AIDS interventions. Health-related quality of life (HRQOL) has become an important indicator to assess outcomes of health interventions, as well as inform patient management and policy development. In HIV research, HRQOL measurement has advanced rapidly in recent years, especially since antiretroviral treatment (ART) services were scaled-up that transformed HIV/AIDS into a chronic illness . AssessmBasically, HRQOL can be assessed using generic or condition specific measures. Generic measure included health status profile or utility (preference-based) measures that provide a summary of HRQOL. Specific measures are those instruments which focus on problems associated with single disease states, patient groups, or areas of function . There hVietnam has one of the fastest growing HIV epidemics in Asia, which was largely driven by high-risk behaviors, including unsafe sex and drug injection ,16. CompA cross-sectional study was conducted in Hanoi, Hai Phong, and Ho Chi Minh City in 2012. These metropolitans represent different geographical areas with the largest HIV epidemics in Vietnam. Ha Noi is the capital of Vietnam with a population of 6 million, among those, 18,108 people living with HIV. Hai Phong is a port city in northern Vietnam of about 1.8 million citizens, among those, 6930 HIV-positive cases reported. Ho Chi Minh City is the biggest southern metropolitan centre, which has the largest HIV-positive population nationwide with 46,507 cases over 8 million residents . Seven hFace-to-face interviews using a structured questionnaire were carried out by well-trained health workers to collect information about patient’s socioeconomic, HIV-related characteristics, and HRQOL. The socioeconomic characteristics included age, gender, marital status, education level, employment, and income. Household’s monthly income was self-reported by summing up all sources of income from each member in 2011; and then stratified into five quintiles. Health behaviors of interest, including drug use, alcohol use, and adherence to ART, were also self-reported by patients during the interview. We used the Alcohol Use Disorders Identification Test - Consumption (AUDIT-C) to assess alcohol use disorders (AUD) in HIV/AIDS patients . It inclThe EuroQOL - 5 Dimensions (EQ-5D) was employed for measuring health-related quality of life of HIV/AIDS patients. It consisted of a weighted sum of five dimensions: Mobility, Self-care, Usual activities, Pain/Discomfort and Anxiety/Depression, which provided a simple descriptive profile and a single index value for health status [h status . The Vieh status . We usedh status . EQ-5D-5h status . Prior th status . BesidesDescriptive statistical analysis was used to describe the socio-demographics and HIV-related characteristics, and EQ-5D-5L health profile of respondents. ANOVA test was used to examine the differences between means of HRQOL of various patient groups.Psychometric properties of the EQ-5D-5L measurement: Internal consistency reliability of measurement was estimated using Cronbach’s alpha. Although EQ-5D consists of multiple dimensions with single items, the use of Cronbach’s alpha for evaluating its reliability has been reported in previous studies [ studies -32. Disc studies ,27,33-36Multivariable linear regression was used to determine factors associated with HRQOL domain’s scores. Since the range of EQ-5D-5L single index and VAS ranged at  and , these scales were left- and right censored. Censoring from above and below the HRQOL scores did not allow us to measure exactly the values which were higher or lower than the range thresholds. Therefore, in regression analysis, we employed censored regression models (Tobit models) to determined factors associated with EQ-5D-5L single index and VAS [ and VAS . Candida and VAS ,27,33. W and VAS ,27,33,38The use of survey data was approved by the Authority of HIV/AIDS Control, Ministry of Health of Vietnam. Ethical approvals granted by the University of Alberta’s Health Research Ethics Board. Written informed consent was obtained from all participants after clearly introduce the survey. Respondents could refuse to participate or withdraw from the interview at any time, and this did not affect their continuation of health care services. Confidentiality was assured using codes of patient’s information, and secured storage was prepared for both paper questionnaires and electronic data set.Of 1016 patients interviewed, 63.8% were male, average age was 35.4 (SD=7.0), 45% had high school education and above, and 20.4% had stable jobs. The average monthly income per capita of their households was roughly US$ 100 in 2011. As for HIV-related characteristics, Table Table Table nd year of treatment. Besides, health behaviors also predicted HRQOL in HIV/AIDS patients. Drug users reported lower VAS score than non-drug users. Patients who had AUD reported lower score in both VAS and EQ-5D-5L single index than others.The mean of EQ-5D-5L single index and VAS was 0.65  = 0.63; 0.67) and 70.3 , respectively  ,36,39. WCompared with previous studies, we found some similar influential factors of HRQOL in HIV/AIDS patients, for example, employment was positively associated with HRQOL ,33. As fst year ART is an important period when we observed a significant reduction in HRQOL. During this period, patients had to adapt with the strict compliance, residual opportunistic infections, and side effects of antiretroviral medications. The adherence should also be maintained during more stable periods of ART afterwards. In the Vietnamese settings, stigma and discrimination were found to be a significant barrier that affected adherence to and HRQOL outcomes of ART [This study has helpful implications for both HRQOL assessments and ART services. The measurement properties of the EQ-5D-5L holds potentials in monitoring changes in HRQOL, which are associated with meaningful clinical indicators, such as, CD4 thresholds, HIV/AIDS progression, or responses to ART treatment. Moreover, it helps identify areas for interventions to improve the health outcomes of patients. In this study, we observed a very high prevalence of reported problems in Anxiety/Depression that suggests the necessity of psychological support during ART for HIV/AIDS patients. As for the patient management, the 1s of ART . The reds of ART ,33,40-42The strengths of this study include the involvement of patients in three epicenters across levels of health systems and geographical areas of Vietnam. In addition, we employed the Thailand tariff for deriving the EQ-5D-5L index, which has close culture and other characteristics with Vietnam. Besides, there were some limitations that should be acknowledged. First, we did not have viral load assessments, a gold standard in monitoring ART outcomes, since viral load tests are costly and not regularly assessed for all HIV/AIDS patients in Vietnam. Second, tests of convergent validity compared only the measures derived from the same EQ-5D instrument. Moreover, the cross-sectional design might be less capable for causal inference as well as for assessing the responsiveness of the EQ-5D-5L in this measurement. In addition, patients at clinics were selected conveniently making the sample not representative for the population of HIV/AIDS patients and limiting the generalizability of study findings.In conclusion, the EQ-5D-5L showed good properties in measuring HRQOL of HIV/AIDS patients and has potentials for monitoring ART outcomes. Integration of HRQOL measurement using EQ-5D-5L in HIV/AIDS clinical practice could be helpful for economic evaluation of HIV/AIDS interventions. Further research to develop a scoring system of the Vietnamese population is recommended.The authors declare no funding support or conflicts of interest.BXT and LTN designed and implemented the survey. BXT and AO analyzed the data. BXT, AO, and LTN wrote the manuscript. All authors read and approved the final manuscript.