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41.

Background

Costs of tuberculosis diagnosis and treatment may represent a significant burden for the poor and for the health system in resource-poor countries.

Objectives

The aim of this study was to analyze patients'' costs of tuberculosis care and to estimate the incremental cost-effectiveness ratio (ICER) of the directly observed treatment (DOT) strategy per completed treatment in Rio de Janeiro, Brazil.

Methods

We interviewed 218 adult patients with bacteriologically confirmed pulmonary tuberculosis. Information on direct (out-of-pocket expenses) and indirect (hours lost) costs, loss in income and costs with extra help were gathered through a questionnaire. Healthcare system additional costs due to supervision of pill-intake were calculated considering staff salaries. Effectiveness was measured by treatment completion rate. The ICER of DOT compared to self-administered therapy (SAT) was calculated.

Principal Findings

DOT increased costs during the treatment phase, while SAT increased costs in the pre-diagnostic phase, for both the patient and the health system. Treatment completion rates were 71% in SAT facilities and 79% in DOT facilities. Costs per completed treatment were US$ 194 for patients and U$ 189 for the health system in SAT facilities, compared to US$ 336 and US$ 726 in DOT facilities. The ICER was US$ 6,616 per completed DOT treatment compared to SAT.

Conclusions

Costs incurred by TB patients are high in Rio de Janeiro, especially for those under DOT. The DOT strategy doubles patients'' costs and increases by fourfold the health system costs per completed treatment. The additional costs for DOT may be one of the contributing factors to the completion rates below the targeted 85% recommended by WHO.  相似文献   
42.
Olivia Oxlade and co-authors introduce a Collection on tuberculosis preventive therapy in people with HIV infection.

The most recent World Health Organization Global Tuberculosis (TB) Report suggests that 50% of people living with HIV (PLHIV) newly enrolled in HIV care initiated tuberculosis preventive treatment (TPT) in 2019 [1]. TPT is an essential intervention to prevent TB disease among people infected with Mycobacterium tuberculosis—some 25% of the world’s population [2]. Without TPT, it is estimated that up to 10% of individuals will progress to TB disease. Among PLHIV, the prognosis is worse. Of the approximately 1.4 million annual deaths from TB, 200,000 occur among PLHIV [1], who experience TB at rates more than 30 times [3] higher than people living without HIV.In 2018, governments at the United Nations High-Level Meeting (UNHLM) on TB committed to rapid expansion of testing for TB infection and provision of TPT [4]. The goal was the provision of TPT to at least 24 million household contacts of people with TB disease and 6 million PLHIV between 2018 and 2022. However, by the end of 2019, fewer than half a million household contacts had initiated TPT, well short of the pace needed to achieve the 5-year target [1]. On the other hand, approximately 5.3 million PLHIV have initiated TPT in the past 2 years [1], with particularly dramatic increases in countries supported by the President’s Emergency Plan for AIDS Relief (PEPFAR) [5]. Globally, among PLHIV entering HIV care programs, TPT initiation rose from 36% in 2017 to 49% in 2018 and 50% in 2019 [6,7].To provide insight into scaling up TPT for PLHIV, it is important to consider each of the many steps involved in the “cascade of care” for TPT. A previous systematic review of studies in several populations receiving TPT concluded that nearly 70% of all people who may benefit from TPT were lost to follow-up at cascade of care steps prior to treatment initiation [8]. To maximize the impact of TPT for TB prevention among PLHIV, the full TPT cascade of care must be assessed to identify problems and develop targeted solutions addressing barriers at each step. Until now, these data had not been synthesized for PLHIV.In order to address important research gaps related to TPT in PLHIV such as this one, we are now presenting a Collection in PLOS Medicine on TPT in PLHIV. In the first paper in this Collection, Bastos and colleagues performed a systematic review and meta-analysis of the TPT cascade of care in 71 cohorts with a total of 94,011 PLHIV [9]. This analysis highlights key steps in the cascade where substantial attrition occurs and identifies individual-level and programmatic barriers and facilitators at each step. In stratified analyses, they found that losses during the TPT cascade were not different in high-income compared to low- or middle-income settings, nor were losses greater in centers performing tests for TB infection (tuberculin skin test [TST] or interferon gamma release assay [IGRA]) prior to TPT initiation.The net benefits of TPT could potentially be increased through greater adoption of shorter rifamycin-based TPT regimens, for which there is increasing evidence of greater safety, improved treatment completion, and noninferior efficacy, compared to isoniazid regimens. Two reviews of rifamycin-based regimens in mostly HIV–negative adults and children concluded that they were as effective for prevention of TB as longer isoniazid-based regimens, with better treatment completion and fewer adverse events [10,11]. However, safety and tolerability of TPT regimens can differ substantially between people with and without HIV, and for rifamycin-based TPT regimens, safety outcomes were actually worse in people without HIV [12], plus there can be important drug–drug interactions between rifamycin-based regimens and antiretroviral drugs [13]. Reviews of studies focused on PLHIV concluded that TPT (regardless of regimen selected) significantly reduced TB incidence [14] and that the benefits of continuous isoniazid in high TB transmission settings outweighed the risks [15]. As part of this Collection, Yanes-Lane and colleagues conducted a systematic review and network meta-analysis of 16 randomized trials to directly and indirectly compare the risks and benefits of isoniazid and rifamycin-based TPT regimens among PLHIV [16]. Their findings highlight the better safety, improved completion, and evidence of efficacy, particularly reduced mortality, with rifamycin-based TPT regimens, while also noting improved TB prevention with extended duration mono-isoniazid regimens. Their review also revealed that few studies exist on some important at-risk populations, such was pregnant women and those with drug-resistant TB infection.In North America, recommendations changed in 2020 to favor shorter rifamycin-based regimens over isoniazid [17], but WHO still favors isoniazid [18], largely due to the lower drug costs. Although drug costs for rifamycins are typically higher than for isoniazid, their shorter duration and better safety profile mean that total costs for care (including personnel costs) may be lower for rifamycin-based regimens, even in underresourced settings [19]. The cost-effectiveness of different TPT regimens among PLHIV in underresourced settings remains uncertain, as well as the impact of antiretroviral therapy (ART), and the use of diagnostic tests for TB infection, such as TST or IGRA on cost efficiency. Uppal and colleagues, in the third paper in this Collection, performed a systematic review and meta-analysis of 61 published cost-effectiveness and transmission modeling studies of TPT among PLHIV [20]. In all studies, TPT was consistently cost-effective, if not cost saving, despite wide variation in key input parameters and settings considered.When comparing access to TPT among PLHIV to household contacts, many would consider the glass is half full, given that almost half of all PLHIV newly accessing care initiated TPT in 2018 and 2019, and the UNHLM goal of 6 million PLHIV initiating TPT was already nearly achieved by the end of 2020. This remarkable achievement is the result of strong recommendations from WHO for TPT among PLHIV for nearly a decade and strong donor support. These policies are, in turn, based on clear and consistent evidence of individual benefits from multiple randomized trials, plus consistent evidence of cost-effectiveness from many economic analyses as summarized in the papers in this Collection. These are useful lessons for scaling up TPT for other target populations, particularly household contacts, of whom less than half a million have initiated TPT, of the 24 million–person target set in 2018.However, the glass of TPT among PLHIV is also half empty. In contrast to the “90-90-90” targets, 50% of PLHIV newly enrolled in care do not initiate TPT, and PLHIV still bear a disproportionate burden of TB. Programmatic scale-up of TPT continues to encounter challenges that need to be overcome in order to translate individual-level success to population-level improvement. The study by Bastos and colleagues in this Collection has identified programmatic barriers including drug stockouts and suboptimal training for healthcare workers, but it also offers useful solutions, including integration of HIV and TPT services [9]. New evidence on the success of differentiated service delivery will also be invaluable to support programmatic scale-up in different settings [21]. Acting on this evidence will be essential to achieve the goal of full access to effective, safe, and cost-effective TPT for PLHIV.  相似文献   
43.
Rhizotoxic effects of many trace metals are known, but there is little information on recovery after exposure. Roots of 3-d-old cowpea (Vigna unguiculata (L.) Walp. cv. Caloona) seedlings were grown for 4 or 12 h in solutions of 960 μM Ca and 5 μM B at two concentrations (which reduce growth by 50 or 85%) of nine trace metals that rupture the outer layers of roots. Measured concentrations were 34 or 160 μM Al, 0.6 or 1.6 μM Cu, 2.2 or 8.5 μM ?Ga, 2.3 or 12 μM Gd, 0.8 or 1.9 μM Hg, 1.0 or 26 μM In, 2.4 or 7.3 μM La, 1.8 or 3.8 μM Ru, and 1.3 or 8.6 μM Sc. Roots were rinsed, transferred to solutions free of trace metals, and regrowth monitored for up to 48 h. Recovery from exposure to Hg occurred within 4 h, but regrowth was delayed for ≥?12 h with Al, Ga, or Ru. There was poor regrowth after 4 or 12 h exposure to Cu, Gd, In, La, or Sc. Roots recovered after being grown for 12 to 48 h in 170 μM Al, 5.1 μM? Ga, 2.0 μM Hg, or 1.4 μM Ru, but the extent of recovery was reduced with longer exposure time. Microscopy showed marked differences in symptoms on roots recovering from exposure to the various trace metals. Differences in (i) concentrations that are toxic, (ii) ability of roots to recover, (iii) time for recovery to occur, and (iv) symptoms that develop, suggest that each trace metal has a unique combination of rhizotoxic effects.  相似文献   
44.
Manganese (Mn) is an essential micronutrient for plant growth but is often toxic in acid or waterlogged soils. Using cowpea (Vigna unguiculata L. Walp.) grown with 0.05-1500 μM Mn in solution, two short-term (48 h) solution culture experiments examined if the effects of cations (Ca, Mg, Na, Al, or H) on Mn nutrition are related to the root cells' plasma membrane (PM) surface potential, ψ(0)(0). When grown in solutions containing levels of Mn that were toxic, both relative root elongation rate (RRER) and root tissue Mn concentration were more closely related to the activity of Mn(2+) at the outer surface of the PM, {Mn(2+)}(0)(0) (R(2)=0.812 and 0.871) than to its activity in the bulk solution, {Mn(2+)}(b) (R(2)=0.673 and 0.769). This was also evident at lower levels of Mn (0.05-10 μM) relevant to studies investigating Mn as an essential micronutrient (R(2)=0.791 versus 0.590). In addition, changes in the electrical driving force for ion transport across the PM influenced both RRER and the Mn concentration in roots. The {Mn(2+)}(b) causing a 50% reduction in root growth was found to be c. 500 to >1000 μM (depending upon solution composition), whilst the corresponding value was 3300 μM when related to {Mn(2+)}(0)(0). Although specific effects such as competition are not precluded, the data emphasize the importance of non-specific electrostatic effects in the Mn nutrition of cowpea seedlings over a 1×10(5)-fold range of Mn concentration in solution.  相似文献   
45.
The Indian black berry (Syzygium cumini Skeels) has a great nutraceutical and medicinal properties. As in other fruit crops, the fruit characteristics are important attributes for differentiation were also determined for different accessions of S. cumini. The fruit weight, length, breadth, length: breadth ratio, pulp weight, pulp content, seed weight and pulp: seed ratio significantly varied in different accessions. Molecular characterization was carried out using PCR based RAPD technique. Out of 80 RAPD primers, only 18 primers produced stable polymorphisms that were used to examine the phylogenetic relationship. A sum of 207 loci were generated out of which 201 loci found polymorphic. The average genetic dissimilarity was 97 per cent among jamun accessions. The phylogenetic relationship was also determined by principal coordinates analysis (PCoA) that explained 46.95 per cent cumulative variance. The two-dimensional PCoA analysis showed grouping of the different accessions that were plotted into four sub-plots, representing clustering of accessions. The UPGMA (r = 0.967) and NJ (r = 0.987) dendrogram constructed based on the dissimilarity matrix revealed a good degree of fit with the cophenetic correlation value. The dendrogram grouped the accessions into three main clusters according to their eco-geographical regions which given useful insight into their phylogenetic relationships.  相似文献   
46.
姬强  孙汉印  Taraqqi AK  王旭东   《生态学杂志》2014,25(4):1029-1035
在连续8年田间定位试验的基础上,分析了关中平原冬小麦 夏玉米复种连作系统2008—2009年连续两个生长季期间不同耕作措施(结合秸秆还田和不还田)对土壤有机碳和水分利用率的影响.结果表明: 相对于传统耕作,保护性耕作有利于土壤有机碳、水分利用效率和作物产量的提高,其中在“深松+秸秆还田”耕作模式下的增幅最高,土壤有机碳含量在0~30 cm土层增幅达到19.5%,水分利用效率和作物产量提高了16.9%和20.5%,而免耕模式则有效提高了0~10 cm土层有机碳含量.在该地区土壤和气候条件下,深松结合秸秆粉碎还田是最理想的耕作模式,最有利于土壤有机碳累积,并提高水分利用效率和作物产量.  相似文献   
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49.
Aquaporin 2 (AQP2) is a small, integral tetrameric plasma membrane protein that is expressed in mammalian kidneys. The specific constitution of this protein and its selective permeability to water means that AQP2 plays an important role in hypertonic urine production. Immunolocalization of AQP2 has been studied in humans, monkeys, sheep, dogs, rabbits, rats, mice and adult cattle. We analyzed the expression of AQP2 in kidneys of 7-month-old Polish-Friesian var. black and white male calves. AQP2 was localized in the principal cells of collecting ducts in medullary rays penetrating the renal cortex and in the collecting ducts of renal medulla. AQP2 was expressed most strongly in the apical plasma membrane, but expression was observed also in the intracellular vesicles and basolateral plasma membrane. Our study provides new information concerning the immunolocalization of AQP2 in calf kidneys.  相似文献   
50.
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