Comprehensive effect of increased calcium content in coal on the selenium emission from coal-fired power plants: Combined laboratory and field experiments

Coal combustion is the major contributor to global toxic selenium (Se) emissions. Inorganic elements in coals significantly affect Se partitioning during combustion. This work confirmed that the calcium (Ca) in ash had a stronger relationship with Se retention at 1300 °C than other major elements. Ca oxide chemically reacted with gaseous Se, and its sintering densification slightly affected Se adsorption capacities (44.45 -1840.71→35.17 -1540.15 mg/kg) at 300 - 1300 °C. Therefore, Ca in coals was identified as having potential for hindering gaseous Se emissions, and coals with increased Ca contents (2.74→5.19 wt%) were used in a 350 MW unit. The decreased Se mass distribution (3.54%→2.63%) in flue gas at air preheater inlet (320 -362 °C) confirmed the effectiveness of increased Ca content on gaseous Se emission reduction. More gaseous Se further condensed and was chemically adsorbed by fly ash when passed through an electrostatic precipitator, resulting in a significant increase in the Se content of fly ash. Additionally, the corresponding Se leaching ratio decreased from 4.88 - 35.74% to 1.87 - 26.31%, indicating enhanced stability of Se enriched in fly ash. This research confirmed the feasibility and environmental safety of sequestration of gaseous Se from flue gas to fly ash by increasing the Ca content in coals.

Density functional theory-based screening of Ti4C3O2-loaded single atoms for efficient selective catalytic oxidation of formaldehyde

Indoor formaldehyde (HCHO) pollution poses a major risk to human health. Low-temperature catalytic oxidation is an effective method for HCHO removal. The high activity and selectivity of single atomic catalysts provide a possibility for the development of efficient non-precious metal catalysts. In this study, the most stable single-atom catalyst Ti-Ti4C3O2 was screened by density functional theory among many single atomic catalysts with two-dimensional (2D) monolayer Ti4C3O2 as the support. The computational results show that Ti-Ti4C3O2 is highly selective to HCHO and O2 in complex environments. The HCHO oxidation reaction pathways are proposed based on the Eley-Rideal (E-R) and Langmuir-Hinshelwood (L-H) mechanisms. According to the reaction energy and energy span models, the E-R mechanism has a lower maximum energy barrier and higher catalytic efficiency than the L-H mechanism. In addition, the stability of the Ti-Ti4C3O2 structure and active center was verified by diffusion energy barrier and ab initio molecular dynamics simulations. The above results indicate that Ti-Ti4C3O2 is a promising non-precious metal catalyst. The present study provides detailed theoretical insights into the catalytic oxidation of HCHO by Ti-Ti4C3O2, as well as an idea for the development of efficient non-precious metal catalysts based on 2D materials.

Modeling of arsenic migration and emission characteristics in coal-fired power plants

After coal combustion, the minerals present in fly ash can adsorb arsenic (As) during flue gas cooling and reduce As emissions. However, a quantitative description of this adsorption behavior is lacking. Herein, the As adsorption characteristics of minerals (Al/Ca/Fe/K/Mg/Na/Si) were investigated, and a model was developed to predict As content in fly ash. Lab-scale experiments and density functional theory calculations were performed to obtain mineral As adsorption potential. Then, the model was established using lab-scale experimental data for 11 individual coals. The model was validated using lab-scale data from ten blended coals and demonstrated acceptable performance, with prediction errors of 2.83-11.45 %. The model was applied to a 350 MW coal-fired power plant (CFPP) with five blended coals, and As concentration in the flue gas was predicted from a mass balance perspective. The experimental and predicted As contents in fly ash were 11.92-16.15 and 9.61-12.55 μg/g, respectively, with a prediction error of 17.39-22.29 %, and those in flue gas were 11.52-16.58 and 5.37-34.04 μg/Nm3. Finally, As distribution in the CFPP was explored: 0.74-1.51 % in bottom ash, 74.05-82.70 % in electrostatic precipitator ash, 0.53-1.19 % in wet flue gas desulfurization liquid, and 0.13-0.73 % in flue gas at the stack inlet.

Effects of temperature on the migration behaviour of arsenic and chromium in tannery sludge under CO2 gasification

To reduce heavy metals (HMs) contamination from tannery sludge, this study investigated the migration behaviour of arsenic (As) and chromium (Cr) at 700-900 °C using CO2 gasification. The HMs enrichment results showed that As contents of ash decreased (6.42→1.87 mg/kg) while Cr contents increased (41.40→78.24 mg/kg) over 700-900 °C. More Si-O bonds and fewer Ca-O bonds with increasing temperature in ash primarily determined this migration behaviour of HMs. Meanwhile, the proportions of toxic As(III) and Cr(VI) declined from 96.02% and 64.26-76.96% and 21.24%, forming As(0) and Cr(III) with less toxicity. This reduction was conducted via two pathways: (i) carbon reduced As(III)/Cr(VI) and (ii) carbon reduced Fe(II)/Fe(III) to Fe(0), then Fe(0) reduced As(III)/Cr(VI) assisted with carbon via Fe(0)→Fe(II)→Fe(III). However, free calcium ions oxidized As(0)/Cr(III) to As(III)/Cr(VI) at 700 ○C. At higher temperatures, silicate glass conversion of ash immobilized free calcium ions and barely oxidized HMs. Furthermore, this study identified the positive effect of increasing temperature on enhancing the stability of HMs in ash by transforming bioavailable HMs into non-bioavailable HMs, which decreased the leaching toxicity and environmental risk. Regarding HMs emissions control and cold gas efficiency, CO2 gasification treatment of tannery sludge is most effective at 800 °C.

Reducing CO/NO and absorbing heavy metals in self-sustained smouldering of high-moisture sludge by regulating inert media with low-cost natural zeolite

Smouldering is a low-energy, low-cost, effective treatment technology for sludge with high moisture. However, combustible gas and pollution in the flue gas limit the low-cost operation. This work proposes a novel method to in-situ reduce gas emissions (CO, NO, VOCs) and absorb heavy metals by regulating inert media with low-cost natural zeolite in self-sustained smouldering of sludge, and the effect of natural zeolite blending ratio on the performance is deeply investigated by fixed-bed and smouldering experiments. Fixed-bed experiments show that adding natural zeolite contributes to the sludge reaction owning to the confined catalysis with porous structure, as observed by the more rapid oxygen consumption, lower CO/NO concentrations. Moreover, smouldering experiments demonstrate that the endothermic dehydroxylation and dehydroxylation processes of the pure natural zeolite decreases the smouldering temperature and the propagation velocity, reduces the pyrolysis layer, but adding natural zeolite significantly reduces the concentrations of CO/NO/VOCs in the flue gas. Furthermore, higher heavy element content in the post-reaction natural zeolite is observed, indicating that the inorganic minerals in natural zeolite can effectively absorb the heavy elements. Taking reaction intensity, CO/NO/VOCs reduction and heavy element absorption into account, adding a small amount of natural zeolite (Sand: Natural-zeolite = 2.90:0.10) may be reasonable with obtaining good performance. Finally, the organic components in condensable liquids of the smouldering flue gas are deeply analyzed, and the main components is 36.7% for amides and 23.41% for nitrogen-containing heterocyclic compounds. This work can provide a possible pathway and useful information for the low-cost application of the sludge smouldring technology.

Experimental investigation on self-sustained smouldering of food-processing sludge with extremely high moisture content: From laboratory-scale to pilot-scale volumetric scale-up

Although smouldering of solid waste with high moisture has shown strong promise in laboratory studies, there are fewer reports about the larger-scale device and continuous operation. This work studies a self-sustaining smouldering treatment of food-processing sludge (FPS) with extremely high moisture (over 85 %) in laboratory- and pilot-scale devices. Results from laboratory-scale experiments show that adding auxiliary fuel is necessary to maintain FPS self-sustaining smouldering, Sand: FPS: Sawdust = 25:5:1 is a reasonable mixing ratio. Then, the self-sustaining smouldering is volumetrically scaled up to the pilot-scale. The smouldering asynchrony in the feedstock is observed due to the non-uniform air flux. Compared to the laboratory-scale, the pilot-scale device presents a similar temperature level but a higher smouldering velocity. Furthermore, a continuous process in the pilot-scale device is successfully performed, and the flue gas concentrations are measured: 15.0 ∼ 16.5 % for O₂, 4000 ∼ 5500 ppm for CO, 155 ∼ 195 ppm for NO_x, 210 ∼ 250 ppm for VOC_s, 55 ∼ 70 ppm for SO₂, 0.0138 ∼ 0.0317 ngTEQ/m³ (at 11 % O₂) for dioxin. These studied results can provide useful information for continuous, low-energy solid waste treatment.

[Research advances on the techniques for diagnosing burn wound depth]

The accurate diagnosis of burn wound depth is particularly important for evaluating the disease prognosis of burn patients. In the past, the diagnosis of burn wound depth often relied on the subjective judgment of doctors. With the continuous development of diagnostic technology, the methods for judging the depth of burn wound have also been updated. This paper mainly summarizes the research progress in the applications of indocyanine green angiography, laser Doppler imaging, laser speckle contrast imaging, and artificial intelligence in the diagnosis of burn wound depth, and compares the advantages and disadvantages of these techniques, so as to provide ideas for accurate diagnosis of burn wound depth.

Nomogram to predict haemorrhagic transformation after stroke thrombolysis: a combined brain imaging and clinical study

AIM

To construct a novel nomogram by integrating computed tomography perfusion (CTP) and clinical parameters for individualised prediction of haemorrhagic transformation (HT) in intravenous thrombolysis (IVT)-treated acute ischaemic stroke (AIS) patients.

METHODS

Anterior circulation AIS patients who underwent IVT at a single centre from January 2018 to June 2020 were reviewed retrospectively. The CTP parameters of two regions of interest (ROI), the entire perfusion lesion areas, and the infract core areas, were assessed. HT was documented by follow-up CT 24 ± 2 h after IVT. Multivariable logistic regression was conducted by including clinical variables and CTP parameters to identify the independent predictors of HT. A nomogram was developed based on the independent predictors. The discriminative value and calibration of the nomogram were tested by concordance indexes (C-indexes) and calibration plots. Internal validation was performed using fivefold cross-validation.

RESULTS

The nomogram was generated using the complete data from 341 patients. Seven variables were included in the final nomogram, including: the relative cerebral blood volume (rCBV), permeability surface (PS), and relative PS (rPS) in infract core areas, the relative time to maximum (rTmax) and rPS in entire perfusion lesion areas, the National Institutes of Health Stroke Scale (NIHSS), and atrial fibrillation (AF). The C-indexes were 0.815 and 0.817 for the nomogram and internal validation. The calibration plots showed excellent agreement.

CONCLUSION

This is the first study establishing a nomogram based on CTP and clinical parameters to predict HT after stroke thrombolysis.

Stability of pacemaker parameters in cardiac amyloidosis patients

 

Cardiac amyloidosis is a rare disease due to the deposition of amyloid fibrils in the heart. Clinical manifestation of the heart includes restrictive heart failure and arrhythmia, when myocardium and conduction system are involved respectively. Arrhythmia can present as atrioventricular block (AVB), and sick sinus syndrome (SSS), therefore cardiac amyloidosis may require permanent pacemaker implantation. However, the stability of pacemaker parameters in cardiac amyloidosis patients remains unknown.

We conducted an observational retrospective study of patients diagnosed with cardiac amyloidosis who underwent permanent pacemaker implantation from January 1, 2011 to December 31, 2019. Base-line data were obtained via Medical Record System. Data of pacemaker parameters were obtained via pacemaker programming at the time of implantation and last follow-up at the clinic.

A total of 10 patients were included in our study, among which 5 patients underwent cardiac biopsy and showed positive result, 4 patients showed positive biopsy result of other tissue and characteristic echocardiography result of restrictive diastolic dysfunction, 1 patient was diagnosed with primary systematic amyloidosis (AL) involving kidney and advanced atrioventricular block. Amyloidosis type of the 10 patients were primary systemic amyloidosis (AL). Among the 10 patients, 3 were female (30.0%), and the mean age was 61.3±3.9. All patients met the indication for permanent pacemaker implantation, including 9 SSS and 1 advanced AVB. 9 patients were implanted with DDD, and 1 with VVI. The middle survival time was 446 (331, 728) days from the time of implantation to last follow-up (June 30, 2020). Two patients died due to disease progression. As for the 7 patients whose baseline and follow-up data were both obtained, pacemaker parameters at baseline were as followed: Atrial Impedance 477.8±115.0 Ω, Atrial P Wave 1.30±0.70 mV, Atrial Threshold 0.75±0.16 V@0.4ms, Ventricular Impedance 551.3±233.4 Ω, Ventricular R Wave 7.99±4.66 mV, Ventricular Threshold 0.76±0.15 V@0.4ms. Pacemaker parameters at follow-up were as followed: Atrial Impedance 426.2±93.2 Ω, Atrial P Wave 1.34±0.71 mV, Atrial Threshold 1.59±1.51 V@0.4ms, Ventricular Impedance 405.8±41.6 Ω, Ventricular R Wave 10.69±6.53 mV, Ventricular Threshold 1.80±1.88 V@0.4ms.

Most patients relieved from cardiac symptoms and severe cardiac complications. A relatively short-term follow-up indicated elevation of Ventricular Threshold (P=0.028), and analysis of other parameters showed insignificant results. Elevation of Ventricular Threshold may be explained by the progression of amyloid fibrils deposition in the heart. Ventricular Threshold of one patient significantly increased from 1.0 V to 6.0 V at 3-month follow-up. Since all patients underwent chemotherapy for the primary amyloidosis, stability of pacemaker parameters may be another way for evaluation. Long-term follow-up is needed for further evaluation.

Funding Acknowledgement

Type of funding sources: None.

[Epidemiological characteristics of local outbreak of COVID-19 caused by SARS-CoV-2 Delta variant in Liwan district, Guangzhou]

Objective: To analyze the epidemiological characteristics of a local outbreak of COVID-19 caused by SARS-CoV-2 B.1.617.2(Delta) variant in Liwan district, Guangzhou, and provide evidence for the further prevention and control of the Delta variant of COVID-19. Methods: From May 21 to June 18, 2021, the incidence data of COVID-19 caused by Delta variant were obtained from National Notifiable Disease Report System of Chinese Disease Prevention and Control Information System and Liwan District Center for Disease Control and Prevention of Guangzhou.Frequency analysis (proportions), histograms, and percentage stacked area plots were used to describe the epidemiological characteristics of the outbreaks. The incubation period and time-varying reproduction numbers (R_t) estimations were used for the further analysis. Results: By June 18, 2021, a total of 127 COVID-19 cases caused by Delta variant was reported in Liwan district. The youngest case was aged 2 years and the oldest was aged 85 years. There were 18.9% (24/127) aged <18 years, 43.3% (55/127) aged 18-59 years, and 37.8% (48/127) aged ≥60 years, the male to female ratio of the cases was 1∶1.35 (54∶73). The cases were mainly retired people (32.3%, 41/127), the jobless or unemployed (18.1%, 23/127), and students (16.5%, 21/127). The infections mainly occurred in Baihedong (70.1%, 89/127) and Zhongnan street (23.6%, 30/127) communities in the southern area of Liwan district. The median incubation period of the Delta variant infection was 6 days (range: 1-15 days). The clinical classification were mainly common type (64.6%, 82/127). The basic reproduction number (R₀) was 5.1, R_t which once increased to 7.3. The transmissions mainly occurred in confined spaces, such as home (26.8%), restaurant (29.1%), neighborhood (3.9%), and market (3.1%), the household clustering was predominant. Close contacts tracing (66.1%) and community screening (33.1%) were the main ways to find the infections. Conclusion: The COVID-19 outbreak caused by Delta variant in Liwan district of Guangzhou was highly contagious, with the obvious characteristics of household clustering and high proportions of cases in adults aged 18-59 years and elderly people aged ≥60 years.

Hydroxytyrosol inhibits apoptosis in ischemia/reperfusion-induced acute kidney injury via activating Sonic Hedgehog signaling pathway

OBJECTIVE

Acute kidney injury (AKI) is a common critical illness in clinic, which seriously threatens the life of patients. The aim of this study was to validate the anti-apoptotic effect of hydroxytyrosol (HT) in ischemia/reperfusion (I/R)-induced AKI.

MATERIALS AND METHODS

The cell model of AKI was established by hypoxia/reoxygenation (H/R), and the animal model of AKI was established by I/R. The apoptosis was observed by Caspase-3 activity assay, flow cytometry and terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) staining. Cell viability was detected by cell counting kit-8 (CCK-8) assay. Protein expression was measured by Western blot and mRNA level was analyzed by quantitative real-time polymerase chain reaction (RT-PCR). Renal function was assessed by measuring serum creatinine (Cr) and blood urea nitrogen (BUN).

RESULTS

H/R induced apoptosis of HK-2 cells and reduced cell viability. When HK-2 cells were pretreated with HT, apoptosis was markedly inhibited, and cell viability was greatly increased. In addition, HT could inhibit I/R-induced apoptosis of rat kidney cells and could notably improve rat kidney function. H/R promoted Sonic Hedgehog (SHH) expression in HK-2 cells, while HT treatment further enhanced SHH expression. Similarly, I/R induces SHH expression in kidney tissue, and HT could further promote SHH expression.

CONCLUSIONS

These results indicated that HT could inhibit apoptosis in I/R-induced AKI via activating SHH signaling pathway.

MiR-1231 enhances docetaxel sensitivity to gallbladder carcinoma cells by downregulating FOXC2

OBJECTIVE

To illustrate the role of microRNA-1231 (miR-1231) in regulating malignant proliferative potential and DTX sensitivity to gallbladder carcinoma (GBC) by regulating FOXC2 level.

PATIENTS AND METHODS

Expression levels of miR-1231 in GBC tissues and paracancerous ones were detected. The relationship between miR-1231 level and clinical parameters of GBC patients was analyzed. After overexpression of miR-1231, changes in proliferative and apoptotic potentials in GBC-SD and NOZ cells were examined by Cell Counting Kit-8 (CCK-8), colony formation assay and flow cytometry, respectively. Regulatory effects of miR-1231 on its downstream gene FOXC2 were determined by Luciferase assay. Finally, the role of miR-1231 in regulating DTX sensitivity to GBC cells was assessed.

RESULTS

MiR-1231 was downregulated in GBC tissues compared to paracancerous ones. GBC patients expressing lower level of miR-1231 had worse tumor staging and larger tumor size. Overexpression of miR-1231 attenuated proliferative potential, and induced apoptosis in GBC cells. FOXC2 was upregulated in GBC and negatively linked to miR-1231. Luciferase activity confirmed that FOXC2 was the target gene binding miR-1231. DTX treatment dose-dependently suppressed viability in GBC cells and overexpression of miR-1231 could enhance DTX sensitivity in GBC. Notably, overexpression of FOXC2 abolished regulatory effects of overexpressed miR-1231 on proliferative and apoptotic potentials in GBC cells.

CONCLUSIONS

MiR-1231 is downregulated in GBC species. Its level is closely linked to tumor staging and tumor size in GBC patients. By downregulating FOXC2, miR-1231 enhances DTX sensitivity to GBC cells and thus alleviates the malignant development of GBC.

Hsa-circ-0068566 inhibited the development of myocardial ischemia reperfusion injury by regulating hsa-miR-6322/PARP2 signal pathway

OBJECTIVE

In recent years, studies have shown that noncoding RNA (circRNA) is an important regulatory molecule involved in cell physiology and pathology. Herein, we analyzed the role of circRNA-68566 in the regulation of myocardial ischemia-reperfusion (I/R) injury by regulating miR-6322/PARP2 signaling pathway.

MATERIALS AND METHODS

Cell viability was checked by CCK-8; LDH concentration, ROS production, MDA, SOD and GSH-Px were measured by corresponding kits; QPCR was used to inspect the expression of circRNA-0068566 and miR-6322 in I/R injury and H9C2 cells; luciferase reporter assay confirmed the direct target effect of circRNA-0068566 and miR-6322; Western blot was used to investigate PARP2 protein expression in I/R injury and H9C2 cells.

RESULTS

We analyzed the regulatory effect of circRNA-68566 on I/R injury and found that circRNA-68566 promoted the proliferation of injured cardiomyocytes in vitro and in vivo. circRNA-68566 and miR-6322 were directly combined to regulate the development of I/R injury. We also confirmed that PARP2 was the target of miR-6322 in I/R injury.

CONCLUSIONS

We believed that circRNA-68566 participated in myocardial ischemia-reperfusion injury by regulating miR-6322/PARP2 signaling pathway, which provided a new possible strategy for the treatment of I/R injury.

Experimental and DFT studies on the characteristics of PbO/PbCl2 adsorption by Si/Al- based sorbents in the simulated flue gas

Mineral oxides are effective in-furnace sorbents used to control lead (Pb) emissions in flue gas at high temperatures. In this paper, the PbO/PbCl₂ adsorption characteristics of sorbents were investigated via experimental and density functional theory (DFT) methods. The results show that Si/Al-based compounds can chemically adsorb Pb, and the adsorption is related to the Si-O and Al-O bonds in the sorbents. Exposed Si and O atoms on SiO₂ surfaces and exposed Al and O atoms on Al₂O₃ surfaces are the active sites for Pb adsorption, and PbO is easier to remove than PbCl₂. Pb adsorption is promoted in a mixture of SiO₂ and Al₂O₃. Doping Si atoms into Al₂O₃(100) promotes PbO adsorption, and doped three-coordinate Si atoms have a more obvious promotion effect than doped two-coordinate Si atoms. Doping Al atoms into SiO₂(001) has no obvious effect on PbO adsorption. The effect of temperature on Pb adsorption was studied by thermodynamic analysis. The Gibbs free energy difference for PbO adsorption on SiO₂(001) increases from -373.04-32.42 kJ/mol as the temperature increases from 300 to 1800 K. High-temperature calcination changes the bond length and bond angle of the system, affecting the stabilities of atomic configurations and decreasing the Pb adsorption capacity.

Deep insight into the effect of NaCl/HCl/SO2/CO2 in simulated flue gas on gas-phase arsenic adsorption over mineral oxide sorbents

Coal combustion is one of the major pathways by which arsenic enters the ecological environment. An effective method to control arsenic emissions in-furnace is to transform the arsenic from a vapour to fly ash particles using mineral sorbents. However, flue gas components have a significant effect on gas-phase arsenic adsorption, which limits the industrial application of mineral sorbents. In this paper, the effect mechanism of flue gas components (NaCl/HCl/SO₂/CO₂) on gas-phase arsenic adsorption over different mineral oxide sorbents was investigated. The results demonstrate that the order of arsenic adsorption is CaO > MgO/Fe₂O₃> NaCl > Al₂O₃ > SiO₂. NaCl promotes the arsenic adsorption of CaO above 800 °C, and the arsenic removal efficiency of CaO with 5 % NaCl is 52.51 % at 900 °C. NaCl inhibits the arsenic adsorption of MgO and Fe₂O₃, and promotes arsenic adsorption by Al₂O₃ and SiO₂. Acid gases inhibit arsenic adsorption by the sorbents and the order of the inhibition intensity of acid gases at 700 °C is HCl > SO₂ > CO₂. The active sites (CaO, FeO, or AlO bonds) in the sorbents are the main reaction sites for arsenic adsorption, and captured arsenic is in the form of AsO₂^1- and AsO₄^3-.

Purification of Plasmodium and Babesia- infected erythrocytes using a non-woven fabric filter

The purification of parasite-infected erythrocytes from whole blood containing leucocytes is crucial for many downstream genetic and molecular assays in parasitology. Current methodologies to achieve this are often costly and time consuming. Here, we demonstrate the successful application of a cheap and simple Non-Woven Fabric (NWF) filter for the purification of parasitized red blood cells from whole blood. NWF filtration was applied to the malaria-parasitized blood of three strains of mice, and one strain of rat, and to Babesia gibsoni parasitized dog blood. Before and after filtration, the white blood cell (WBC) removal rates and red blood cell (RBC) recovery rates were measured. After NWF filter treatment of rodent malaria-infected blood, the WBC removal rates and RBC recovery rates were, for Kunming mice: 99.51%±0.30% and 86.12%±8.37%; for BALB/C mice: 99.61%±0.15% and 80.74%±7.11%; for C57 mice: 99.71%±0.12% and 84.87%±3.83%; for Sprague-Dawley rats: 99.93%±0.03% and 83.30%±2.96%. Microscopy showed WBCs were efficiently removed from infected dog blood samples, and there was no obvious morphological change of B. gibsoni parasites. NWF filters efficiently remove leukocytes from malaria parasite-infected mouse and rat blood, and are also suitable for filtration of B. gibsoni-infected dog blood.

[Immune characteristics of Plasmodium reinfections in mice following chloroquine cure of primary Plasmodium infections]

OBJECTIVE

To investigate the disease progression and immunoprotective characteristics in mice re-infected with homogeneous/heterogeneous Plasmodium strains following cure of Plasmodium infections with chloroquine at the peak of parasitemia.

METHODS

C57BL/6 mice were infected with the non-lethal P. yoelii 17XNL strain, and half of mice were given treatment with chloroquine at the peak of parasitemia (9 days post-infection), while the other mice were self-cured naturally. Then, all cured mice were re-infected with the equivalent lethal P. yoelii 17XL or P. berghei ANKA strain 90 days following primary Plasmodium infections. The parasitemia levels during primary infections and reinfections were measured by microscopic examinations of Giemsa-stained thin blood films, and the levels of the IgG antibody in sera and the percentages of memory T cell subsets in spleen cells were detected in mice using ELISA and flow cytometry before and after parasite reinfections, respectively.

RESULTS

Following primary infections with the P. yoelii 17XNL strain, the serum IgG antibody levels were (5.047 ± 0.924) pg/mL in the selfcured mice and (4.429 ± 0.624) pg/mL in the chloroquine-treated mice, respectively (t = 0.437, P > 0.05), which were both significantly higher than that in the uninfected mice (1.624 pg/mL ± 0.280 pg/mL) (F = 22.522, P < 0.01). There was no significant difference in the serum IgG antibody level among self-cured and chloroquine-treated mice re-infected with the P. yoelii 17XL strain or the P. berghei ANKA strain (F = 0.542, P > 0.05); however, the serum IgG antibody levels were all significantly higher in selfcured and chloroquine-treated mice re-infected with the P. yoelii 17XLstrain[(15.487±1.173)pg/mLand(15.965±1.150)pg/mL] or the P. berghei ANKA strain [(14.644 ± 1.523) pg/mL and (15.185 ± 1.333) pg/mL] relative to primary infections (F = 67.383, P < 0.01). There was no significant difference in the proportion of CD4⁺ [(34.208 ± 2.106), (32.820 ± 1.930), (34.023 ± 2.289), (35.608 ± 1.779) pg/mL] or CD8⁺ T memory cells [(17.935 ± 2.092), (18.918 ± 2.823), (17.103 ± 1.627), (17.873 ± 1.425) pg/mL] in self-cured and chloroquine-treated mice with primary infections with the P. yoelii 17XNL strain followed by re-infections with the P. yoelii 17XL strain or the P. berghei ANKA strain (F = 0.944 and 0.390, both P > 0.05); however, the proportions of the CD4⁺ or CD8⁺ T memory cells were significantly greater in self-cured and chloroquine-treated mice with primary infections with the P. yoelii 17XNL strain followed by re-infections with the P. yoelii 17XL strain or the P. berghei ANKA strain than in mice with primary infections (F = 50.532 and 21.751, both P < 0.01).

CONCLUSIONS

The cure of murine Plasmodium infections with chloroquine does not affect the production of effective immune protections in mice during parasite re-infections. Following a primary infection, mice show a protection against re-infections with either homogeneous or heterogeneous Plasmodium strains, and a higher-level resistance to re-infections with homogeneous parasite strains is found than with heterogeneous strains.

[Analysis of factors related to recanalization of intramural hematoma-type carotid artery dissection]

Objective: To investigate the factors related to recanalization of intramural hematoma-type carotid artery dissection (CAD). Methods: Retrospective analysis was performed on 56 patients (61 CADs) with intramural-hematoma type CAD confirmed by multimodal imaging examination based on cervical vascular ultrasound (CDU) in the Stroke Center of the First Affiliated Hospital of Suzhou University from August 2015 to May 2019. The clinical and imaging data were collected, and the time from onset to visit is bounded by 14 days. CDU follow-up was performed at 3, 6, and 12 months after the onset. According to the results of the 12-month follow-up, patients were divided into complete recanalization group and incomplete recanalization group. The clinical data, ultrasonic manifestations and drug treatment of patients between the two groups were compared. Multivariate logistic regression analysis was used to analyze the related factors affecting vascular recanalization. Results: Vascular recanalization: the rates of complete recanalization at 3, 6 and 12 months were 42.6% (26/61), 55.7% (34/61) and 59.0% (36/61), respectively. While among the 25 vessels in the incomplete recanalization group, 26.2% (16/61) showed residual stenosis and 14.8% (9/61) showed persistent occlusion. Comparison between the complete recanalization group and the incomplete recanalization group: the differences in the proportion of time from onset to visit ≤ 14 days, the echo type of intramural hematoma, and the proportion of vascular occlusion were statistically significant (all P<0.05). Multivariate logistic regression analysis showed that the time from onset to visit ≤14 days (OR=5.625, 95%CI: 1.302-24.293, P=0.021), and the hypoechoic intramural hematoma (OR=4.888, 95%CI: 1.304-18.320, P=0.019) were positively correlated with complete recanalization, while the dissection vascular occlusion (OR=0.234, 95%CI: 0.059-0.932, P=0.039) was negatively correlated with complete recanalization. Conclusions: CDU showed that hypoechoic intramural hematoma-type CAD treated with standard medications in the acute phase had a higher complete recanalization rate, while the recanalization rate of patients with dissecting vessel occlusion decreased. Early evaluation can provide a basis for clinical individualized treatment.

Big Data and Artificial Intelligence： New Insight into the Estimation of Postmortem Interval

Abstract

The estimation of postmortem interval （PMI） is a core issue in forensic practice. A large amount of time-dependent data can be produced in the decomposition process of a body, however, such multidimensional data cannot be comprehensively and effectively analyzed and utilized by any existing conventional PMI estimation method. As a rapidly developing information technology, artificial intelligence （AI） has significant advantages in big data processing, due to it's comprehensiveness, efficiency and automation. Some scholars have already applied it to researches on the estimation of PMI, showing it's significant advantages in terms of accuracy and development prospect. This article reviews the significance, mode and progress of application of AI in PMI estimation and provides some suggestions and prospects for future study.

Chromosomal abnormalities detected by karyotyping and microarray analysis in twins with structural anomalies

OBJECTIVES

To evaluate the incidence and types of chromosomal abnormalities detected in twins with structural anomalies and compare their distribution according to chorionicity and amnionicity and by structural-anomaly type. The added value of chromosomal microarray analysis (CMA) over conventional karyotyping in twins was also estimated.

METHODS

This was a single-center, retrospective analysis of 534 twin pregnancies seen over an 11-year period, in which one or both fetuses were diagnosed with congenital structural anomalies on ultrasound. The ultrasound findings and invasive prenatal diagnostic results were reviewed. Twin pregnancies were categorized as monochorionic monoamniotic (MCMA), monochorionic diamniotic (MCDA) or dichorionic diamniotic (DCDA). Chromosomal abnormalities detected by G-banding karyotyping and/or CMA were analyzed by chorionicity and amnionicity and by structural-anomaly type.

RESULTS

The 534 twin pairs analyzed comprised 25 pairs of MCMA, 112 pairs of MCDA and 397 pairs of DCDA twins. Of the 549 fetuses affected by structural anomalies, 432 (78.7%) underwent invasive prenatal testing and cytogenetic results were obtained. The incidence of overall chromosomal abnormalities in the DCDA fetuses (25.4%) was higher than that in the MCMA (3.7%) and MCDA (15.3%) fetuses. The incidence of aneuploidy was significantly higher in the DCDA group (22.8%) than in the MCMA (0.0%) and MCDA (12.4%) groups. The incidence of chromosomal abnormalities detected in fetuses, with anomalies of the cardiovascular, faciocervical, musculoskeletal, genitourinary and gastrointestinal systems, was higher in the DCDA group than in the MCDA group. In both the DCDA and MCDA groups, hydrops fetalis was associated with the highest incidence of chromosomal abnormality; of these fetuses, 67.6% had Turner syndrome (45,X). Pathogenic copy-number variations (CNVs) undetectable by karyotyping were identified by CMA in five (2.0%; 95% CI, 0.3-3.7%) DCDA fetuses. No pathogenic CNVs were found in MCMA and MCDA twins.

CONCLUSIONS

Dichorionic twins with structural anomalies have a higher risk of chromosomal abnormalities, especially aneuploidies, than do monochorionic twins. The incremental diagnostic yield of CMA over karyotyping seems to be lower (2.0%) in twins than that reported in singleton pregnancy. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

[Clinical application of HRCT three-dimensional reconstruction in traumatic ossicular chain interruption]

Objective:To investigate the clinical value of HRCT three-dimensional reconstruction technique in traumatic auditory chain traumatic fracture. Method:The clinical data of 14 patients with traumatic ear ossicular chain interruption were analyzed retrospectively. To evaluate the injury site and degree of the auditory chain before surgery, all the 14 patients underwent,HRCT scanning and three-dimensional reconstruction. The reconstructed auditory chain was observed from multiple angles and compared with the surgical exploration results under microscope. Result:The coincidence rate between ossicular chain injury observed by temporal bone HRCT scan before operation and ossicular chain injury observed during surgery was only 28.57%, the coincidence rate between ossicular chain injury observed during surgery and ossicular chain injury observed by three-dimensional reconstruction is 85.71%.Therefore, three-dimensional reconstruction imaging technique could give the doctor more clearly and stereoscopic images for the destruction of ossicular chain. Conclusion:Preoperative three-dimensional reconstruction can display and diagnosis of auditory ossicular chain destruction more clearly. It can be used to accurately evaluate auditory ossicular chain pathological changes, to develop individualized surgical plans and assess the risk of surgery.

Relationship between CT angiography-derived collateral status and CT perfusion-derived tissue viability

AIM

To explore the relationship between computed tomography (CT) angiography (CTA)-derived collateral status and CT perfusion (CTP)-derived tissue viability.

MATERIALS AND METHODS

Patients having middle cerebral artery (MCA) M1/M2 segment and/or internal carotid artery (ICA) occlusion and within 12 hours of onset were included. Collateral was graded from 0 to 3 on maximum intensity projection (MIP) images of CTA. The area with relative cerebral blood flow (rCBF) <30% or time-to-maximum (Tmax) >10 or >12 or >14 seconds was defined as the infarct core, and Tmax >6 seconds as the penumbra. Kruskal-Wallis and Spearman's correlation tests were performed to assess the correlation between collateral grade and infarct size or mismatch ratio.

RESULTS

Eighty-three patients were enrolled and 52 of them met the inclusion criteria. Infarct size defined by rCBF <30% or Tmax >10 or >12 or >14 seconds and mismatch ratios were significantly different among the four groups. The correlation between collateral grades and infarct core using rCBF <30% (ρ=-0.814, p<0.01) was better than that defined by Tmax >10s, >12s or >14s. Mismatch ratio for the infarct core defined by rCBF <30% (ρ=0.945, p<0.01) had the best correlation with collateral grades.

CONCLUSION

Patients with good collaterals show a smaller infarct core and higher mismatch ratio. Infarct size defined by rCBF <30% and mismatch ratio defined by rCBF <30% and Tmax >6 seconds appear to be more correlated with collaterals in AIS patients.

Decrease of FGF19 contributes to the increase of fasting glucose in human in an insulin-independent manner

PURPOSE

The ileum-derived fibroblast growth factor 19 (FGF19) plays key roles in hepatic glucose homeostasis in animals in an insulin-independent manner. Here, we analyzed the association of FGF19 with glucose effectiveness (GE, the insulin-independent glucose regulation), as well as hepatic glucose production (HGP) in Chinese subjects.

METHODS

GE was measured by frequently sampled intravenous glucose tolerance test (FSIVGTT) in normal glucose tolerance (NGT), isolated-impaired glucose tolerance (I-IGT), and isolated-impaired fasting glucose (I-IFG) subjects. The oral glucose tolerance test-derived surrogate of GE (oGE) was determined in NGT, I-IFG, combined glucose intolerance (CGI), and type 2 diabetes (T2DM) subjects. HGP was assessed by labeled ([3-³H]-glucose) hyperinsulinemic-euglycemic clamp in NGT subjects. Insulin secretion and sensitivity were calculated by the hyperglycemic and hyperinsulinemic-euglycemic clamps in a subgroup of NGT, I-IGT, and I-IFG subjects. Serum FGF19 levels were determined by ELISA.

RESULTS

FGF19 positively correlated with GE (r = 0.29, P = 0.004) as determined by FSIVGTT. The result was further confirmed by oGE (r = 0.261, P < 0.001). FGF19 was negatively associated with FPG (r = - 0.228, P = 0.025), but the association no longer existed after adjusting for GE (r = - 0.177, P = 0.086). FGF19 was negatively associated with basal HGP (r = - 0.697, P = 0.006). However, the correlation between FGF19 and insulin secretion and sensitivity were not found.

CONCLUSIONS

FGF19 levels are associated positively with GE and negatively with HGP. The increase of FPG in human is at least partially due to the decrease of FGF19 in an insulin-independent manner.

Effect of NT-3 on infection-induced memory impairment of neonatal rats

OBJECTIVE

To explore the effect of neurotrophin-3 (NT-3) messenger ribonucleic acid (mRNA) in the hippocampus on infection-induced memory impairment of neonatal rats.

MATERIALS AND METHODS

80 female Sprague-Dawley (SD) rats in the neonatal stage were selected to establish memory impairment model by bacterial meningitis infection. Rats were randomly divided into experimental group (n=40) and control group (n=40). Rats in experimental group were injected with β-amyloid precursor protein 319-335 peptide APP17p into brain tissue to up-regulate the expression of NT-3, and the rats in control group didn't receive treatment. Behavioral changes of rats were observed in Morris water maze and passive avoidance experiment. Apoptosis of nerve cells was detected by terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) method and Fluoro-Jade B method. NT-3 mRNA expression level was measured via reverse transcription polymerase chain reaction (RT-PCR).

RESULTS

NT-3 expression level in experimental group was higher than that in control group (p<0.05). Apoptosis rate of nerve cells in experimental group was lower than that in control group, but the learning and memory ability of rats in experimental group was better than that in control group (p<0.05).

CONCLUSIONS

Reduced NT-3 expression level may be correlated with the occurrence of meningitis because NT-3 can suppress nerve cell apoptosis and ameliorate learning and memory impairment to a certain extent to exert neuroprotective effects.

[Efficacy and mechanism of loading dose clopidogrel in patients with transient ischemic attack and minor stroke]

Objective: To assess outcome, safety and possible mechanism of loading dose clopidogrel in patients with transient ischemic attack (TIA) and minor stroke. Methods: We reviewed patients with confirmed TIA and minor stroke admitted between July 2016 and December 2017 into the First Affiliated Hospital of Soochow University. Loss-of-function allele carriers of CYP2C19 were included and randomly divided into loading dose group (first dose of 300 mg clopidogrel) and standard dose group (first dose of 75 mg clopidogrel), 100 mg aspirin was gave at the same time, followed by aspirin 100 mg/d plus clopidogrel 75 mg/d maintaining for 20 days. Platelet aggregation (maximum aggregation ratio, MAR) induced by Adenosine diphosphate (ADP) was examined before and 3 days after administration. The National Institutes of Health Stroke Scale (NIHSS) score method was employed to assess the NIHSS scores before and after treatment in each group of patients; the modified Rankin Scale (mRS) was used to assess the 3-month functional outcome. Results: There was no significant difference in baseline data between the two groups (P>0.05).The proportion of early neurological function improvement in the two groups was 75.0% and 54.8%, and the difference was statistically significant (χ(2)=4.498, P=0.034). The 3-month prognosis was 79.5% and 61.3%, and the difference was statistically significant (χ(2)=4.000, P=0.045). Adverse events: 1 case in the loading dose group, 1 case in the standard dose group, the difference was not statistically significant (2.3% vs 1.6%, χ(2)=0.061, P=0.806). After 3 days of antiplatelet therapy, the MAR of the loading dose group decreased (11%±8%), and the MAR of the standard dose group decreased (9%±4%), the difference was statistically significant (P=0.013).In the loading dose group, there were 32 (72.7%)CYP2C19*2 carriers and 42 (95.5%)CYP2C19*2+*3 carriers; early neurological function improvement in 33 cases, accounting for 93.8% and 76.2%, respectively, and the difference was statistically significant (χ(2)=4.122, P=0.042). There were 35 patients with good prognosis in 3 months, accounting for 96.9% and 81.0%, respectively. The difference was statistically significant (χ(2)=4.310, P=0.038); MAR of CYP2C19*2 carrier was decreased (15%±5%), and MAR of CYP2C19*2+*3 carrier was decreased (12%±8%). The difference was statistically significant (P=0.039). Conclusions: Loading dose clopidogrel can improve the clinical prognosis of minor stroke/TIA without increasing the risk of bleeding. Loading dose clopidogrel may improve the prognosis of minor stroke/TIA by decreasing MAR of CYP2C19*2 carriers.

[Association between the ratio of early diastolic transmitral velocity to early diastolic mitral annular velocity and invasive measured left atrial pressure in patients with atrial fibrillation and preserved left ventricular ejection fraction]

Objective: To evaluate the association between the ratio of early diastolic transmitral velocity to early diastolic mitral annular velocity (E/E') and left atrial pressure (LAP) estimated from invasive catheter measurements in patients with atrial fibrillation (AF). Methods: A total of 46 consecutive patients with non-valvular AF and preserved left ventricular ejection fraction (LVEF) admitted in our department to receive the first radiofrequency ablation from May to July 2017 were included. All patients underwent echocardiography at 24-48 hours before radiofrequency ablation, and LAP was invasively measured during the ablation procedure. According to mean LAP, patients were divided into 2 groups of normal LAP (LAP≤12 mmHg(1 mmHg=0.133 kPa, n=31) and elevated LAP (LAP>12 mmHg, n=15). Linear correlation analysis was used to evaluate the relationship between E/E' and LAP. Results: E/E' correlated well with LAP (septal E/E' (E/E'(sep)), r= 0.397, P=0.006; lateral E/E' (E/E'(lat)), r=0.433, P=0.003; mean E/E' (E/E'(mean)), r=0.431, P=0.003). Using receiver operating characteristic analysis, the optimal cut-off for E/E'(sep) was 12.5 (sensitivity 73.3%, specificity 67.7%), E/E'(lat) was 10.8 (sensitivity 80.0%, specificity 77.4%), E/E'(mean) was 11.0 (sensitivity 86.7%, specificity 64.5%) to predict mean LAP>12 mmHg. Conclusion: E/E', especially the E/E'(lat), is positively correlated with LAP in patients with AF and preserved LVEF, and may be used to estimate the diastolic function in AF patients with preserved LVEF.

Polydopamine–polyethylene glycol–albumin antifouling coatings on multiple substrates

Polydopamine–PEG coatings on different substrates: effects of PDA layer properties on PEG grafting and anti-biofouling properties.

Describing the quality of life of boys with haemophilia in China: Results of a multicentre study using the CHO-KLAT

INTRODUCTION

The treatment of haemophilia varies across countries and across regions within some countries. Similar variation has been observed in health-related quality of life (HR-QoL). Relatively little is known about the HR-QoL of boys with haemophilia in China.

AIM

The aim of this study was to describe the HR-QoL of boys with haemophilia in China using the Canadian Haemophilia Outcomes-Kids Life Assessment Tool (CHO-KLAT).

METHODS

Boys (4-18 years of age) with haemophilia and their parents were enroled in a cross-sectional study. All parents/guardians of study subjects were requested to complete a CHO-KLAT questionnaire during a clinic visit, and report on several other clinical and socioeconomic factors in the past year. Boys who were > 7 years also completed the CHO-KLAT.

RESULTS

A total of 269 parents of boys with haemophilia, from 13 hospitals in 12 provinces, were enroled during 2014. The boys ranged from 4.0 to 17.9 years of age; 91% had haemophilia A, most had moderate (52%) or severe (36%) disease, and most were receiving sub-optimal on-demand therapy or low-dose prophylactic therapy. Child self-report CHO-KLAT scores were available for 171 boys ≥7 years of age and ranged from 24.2 to 85.3 with a mean of 57.6 (n = 171). Parent proxy-reported CHO-KLAT scores ranged from 25.0 to 88.7 with a mean of 55.1 (n = 269).

CONCLUSION

HR-QoL scores in boys with haemophilia in China were substantially lower than reported from Canadian and European boys with haemophilia. Longer term prospective studies are required to examine the factors impacting the HR-QoL for boys with haemophilia in China.

[Effect of 21-gene recurrence score on chemotherapy decisions for patients with estrogen receptor-positive, epidermal growth factor receptor 2-negative and lymph node-negative early stage-breast cancer]

Objective: To investigate the effect of 21-gene recurrence score on adjuvant chemotherapy decisions for patients with estrogen receptor (ER)-positive, epidermal growth factor receptor 2 (HER-2)-negative and lymph node (LN)-negative early stage-breast cancer. Methods: One hundred and forty-eight patients with ER+ , HER-2- and LN- early stage breast cancer were recruited in the Ruijin hospital, Shanghai Jiao Tong University School of Medicine. The 21-gene recurrence score (RS)assay was performed and systemic therapeutic decisions were made before and after knowing the RS results under multidisciplinary discussion. The effects of RS assay and the other influential factors on adjuvant chemotherapy decision were further analyzed. Results: After knowing the RS results, treatment decisions were changed in 26 out of 148 patients(17.6%). Among them, 9 out of 26 patients were not recommended for chemotherapy; 16 of 26 had treatment recommendation changed to chemotherapy, and chemotherapy regimen was changed in the last one patient. Multivariate analysis showed that RS, age and histological grade were independent factors of decision-making for adjuvant chemotherapy. Conclusion: Our results suggest that 21-gene recurrence score significantly influences decision making for adjuvant chemotherapy in patients with ER+ , HER-2- and LN- early stage breast cancer.

[Analysis of the factors influencing adjuvant chemotherapy decisions for triple negative breast cancer]

Objective: To analyze adjuvant chemotherapy decisions for triple negative breast cancer (TNBC), and explore the influencing factors in the multidisciplinary treatment (MDT) modality. Methods: A retrospective analysis was performed. The cases with invasive TNBC who underwent surgery and MDT discussion for adjuvant treatment in Ruijin Hospital, from April 2013 to June 2015, were recruited. The patients' clinicopathological characteristics were analyzed and adjuvant treatment suggestions from MDT were obtained. Here the chemotherapy decision alteration was defined as a disagreement in chemotherapy or not, or inconsistence in regimens between the attending doctor and the multidisciplinary team. Results: A total of 194 patients aged ≤70 years old were enrolled in the multidisciplinary discussion, and 187 patients (96.4%) were suggested to receive chemotherapy. When compared the opinions of the attending doctor to suggestions of the multidisciplinary team, we found that the percentage of chemotherapy decision alteration reached 22.7% (39/172), of which 94.9% (37/39) were inconsistence in chemotherapy regimens. There were 119 patients who were recommended to receive epirubicin plus cyclophosphamide (EC) followed by docetaxel (T) or weekly paclitaxel (wP) regimens. Before the announcement of results for the E1199 trial, EC-T accounted for 62.5% (55/88), and EC-wP accounted for 37.5% (33/88) for this group of patients. After that, the proportion of EC-T was decreased to 22.6% (7/31) and proportion of EC-wP increased to 77.4%(24/31) (P<0.001). In addition, a total of 20 patients were suggested to receive platinum based chemotherapy. The proportions were 9.3% in cases with invasive ductal carcinoma, and 33.3% in cases with metaplastic carcinoma, respectively (P=0.016). Conclusions: The adjuvant chemotherapy decision for TNBC patients is altered in 22.7% of the patients after MDT discussion. After the announcement of SABCS E1199 results, more patients are suggested to receive EC followed by weekly paclitaxel. There is a lack of detailed evidence for platinum based adjuvant chemotherapy for TNBC, and more patients with metaplastic carcinoma receive platinum based adjuvant chemotherapy.

Monetary incentives for provision of syphilis screening, Yunnan, China

Problem

Early detection of syphilis-infected people followed by effective treatment is essential for syphilis prevention and control.

Approach

Starting in 2010 the local health authority in Yunnan province, China, developed a network of 670 service sites for syphilis testing, diagnosis and treatment or for testing-only with referral for further diagnosis and treatment. Point-of-care tests for syphilis and syphilis interventions were integrated into the existing human immunodeficiency virus (HIV) prevention and control programme. To improve the syphilis services, a pay-for-performance scheme was introduced in which providers were paid for testing and treating patients.

Local setting

Yunnan province is the region hardest hit by HIV infection and disproportionately burdened with syphilis cases in China.

Relevant changes

The proportion of attendees at voluntary counselling and testing clinics who were tested for syphilis increased from 46.2% (32 877/71 162) in 2010 to 98.2% (68 012/69 259) in 2015. Syphilis-infected cases treated with the recommended therapy increased from 26.6% (264/993) in 2010 to 82.5% (453/549) in 2015 at designated testing, diagnosis and treatment sites.

Lessons learnt

The strategy greatly increased the uptake of syphilis testing and treatment among people at risk. Introduction of point-of-care tests for syphilis increased coverage of the testing services. Introduction of a pay-for-performance scheme seemed to motivate health-care providers to undertake syphilis intervention services.