Targeted Anti-Cancer Provascular Therapy Using Ultrasound, Microbubbles, and Nitrite to Increase Radiotherapy Efficacy.

Hypoxia is an important mechanism of resistance to radiation therapy in many human malignancies including prostate cancer. It has been recently shown that ultrasound targeted microbubble cavitation (UTMC) can increase blood perfusion in skeletal muscle by triggering nitric oxide signaling. Interestingly, this effect was amplified with a sodium nitrite coinjection. Since sodium nitrite has been shown to synergize with radiotherapy (RT), we hypothesized that UTMC with a sodium nitrite coinjection could further radiosensitize solid tumors by increasing blood perfusion and thus reduce tumor hypoxia. We evaluated (1) the ability of UTMC with and without nitrite to increase perfusion in muscle (mouse hindlimbs) and human prostate tumors using different pulse lengths and pressure; (2) the efficacy of this approach as a provascular therapy given directly before RT in the human prostate subcutaneous xenografts PC3 tumor model. Using long pulses with various pressures, in muscle, the provascular response following UTMC was strong (6.61 ± 4.41-fold increase in perfusion post-treatment). In tumors, long pulses caused an increase in perfusion (2.42 ± 1.38-fold) at lower mechanical index (MI = 0.25) but not at higher MI (0.375, 0.5, and 0.750) when compared to control (no UTMC). However, when combined with RT, UTMC with long pulses (MI = 0.25) did not improve tumor growth inhibition. With short pulses, in muscle, the provascular response following UTMC (SONOS) + nitrite was strong (13.74 ± 8.60-fold increase in perfusion post-treatment). In tumors, UTMC (SONOS) + nitrite also caused a provascular response (1.94 ± 1.20-fold increase in perfusion post-treatment) that lasted for at least 10 min, but not with nitrite alone. Interestingly, the blunted provascular response observed for long pulses at higher MI without nitrite was reversed with the addition of nitrite. UTMC (SONOS) with and without nitrite caused an increase in perfusion in tumors. The provascular response observed for UTMC (SONOS) + nitrite was confirmed by histology. Finally, there was an improved growth inhibition for the 8 Gy RT dose + nitrite + UTMC group vs 8 Gy RT + nitrite alone. This effect was not significant with mice treated by UTMC + nitrite and receiving doses of 0 or 2 Gy RT. In conclusion, UTMC + nitrite increased blood flow leading to an increased efficacy of higher doses of RT in our tumor model, warranting further study of this strategy.

Mastomys natalensis (Smith, 1834) as a natural host for Schistosoma haematobium (Bilharz, 1852) Weinland, 1858 x Schistosoma bovis Sonsino, 1876 introgressive hybrids.

Cercarial emission of schistosomes is a determinant in the transmission to the definitive host and constitutes a good marker to identify which definitive host is responsible for transmission, mainly in introgressive hybridization situations. Our goal was to test the hypothesis that micro-mammals play a role in Schistosoma haematobium, S. bovis, and/or S. haematobium x S. bovis transmission. Small mammal sampling was conducted in seven semi-lacustrine villages of southern Benin. Among the 62 animals trapped, 50 individuals were investigated for Schistosoma adults and eggs: 37 Rattus rattus, 3 Rattus norvegicus, 9 Mastomys natalensis, and 1 Crocidura olivieri. Schistosoma adults were found in four R. rattus and two M. natalensis, with a local prevalence reaching 80% and 50%, respectively. Two cercarial chronotypes were found from Bulinus globosus experimentally infected with miracidia extracted from naturally infected M. natalensis: a late diurnal and nocturnal chronotype, and an early diurnal, late diurnal, and nocturnal chronotype. The cytochrome C oxidase subunit I mtDNA gene of the collected schistosomes (adults, miracidia, and cercariae) belonged to the S. bovis clade. Eleven internal transcribed spacer rDNA profiles were found; four belonged to S. bovis and seven to S. haematobium x S. bovis. These molecular results together with the observed multi-peak chronotypes add M. natalensis as a new host implicated in S. haematobium x S. bovis transmission. We discuss the origin of the new chronotypes which have become more complex with the appearance of several peaks in a 24-h day. We also discuss how the new populations of offspring may optimize intra-host ecological niche, host spectrum, and transmission time period.

[The optimal approach to severe facial trauma following a horse's kick]. / Optimale behandeling van ernstig aangezichtstrauma na trap van paard.

A 15-year-old girl was brought to the emergency department of a hospital by ambulance with extensive facial trauma following a horse's kick. The considerable impact resulted in a combination of injuries to the bone, teeth and soft tissue. Following the transfer from the ambulance, the AE physician immediately consulted an oral and maxillofacial surgeon. Consequently, the patient could be brought to the operating theatre almost straight after stabilisation. There, the oral and maxillofacial surgeon first repositioned her teeth in anatomical position, followed by repositioning and fixation of the mandibular fracture. Next, the teeth in the upper front were stabilised with an acid-etch composite splint and the lip was reconstructed.

Low Intensity Ultrasound Mediated Liposomal Doxorubicin Delivery Using Polymer Microbubbles.

Cardiotoxicity is the major dose-limiting factor in the chemotherapeutic use of doxorubicin (Dox). A delivery vehicle that can be triggered to release its payload in the tumoral microvasculature but not in healthy tissue would help improve the therapeutic window of the drug. Delivery strategies combining liposomal encapsulated Dox (LDox), microbubbles (MBs), and ultrasound (US) have been shown to improve therapeutic efficacy of LDox, but much remains to be known about the mechanisms and the US conditions that maximize cytotoxicity using this approach. In this study, we compared different US pulses in terms of drug release and acute toxicity. Drug uptake and proliferation rates using low-intensity US were measured in squamous cell carcinoma cells exposed to LDox conjugated to or coinjected with polymer MBs. The aims of this study were: (1) to compare the effects of low- and high-pressure US on Dox release kinetics; (2) to evaluate whether conjugating the liposome to the MB surface (DoxLPX) is an important factor for drug release and cytotoxicity; and (3) to determine which US parameters most inhibit cell proliferation and whether this inhibition is mediated by drug release or the MB/US interaction with cells. Low-pressure US (170 kPa) at high duty cycle (stable cavitation) released up to ∼ 70% of the encapsulated Dox from the DoxLPX, thus improving Dox bioavailability and cellular uptake and leading to a significant reduction in cell proliferation at 48 h. Flow cytometry showed that US generating stable oscillations of DoxLPX significantly increased cellular Dox uptake at 4 h after US exposure compared to LDox. Drug uptake was correlated with cytotoxicity at 48 h. Our results demonstrate that Dox-containing liposomes conjugated to polymer MBs can be triggered to release ∼ 70% of their payload using noninertial US. Following release, Dox became bioavailable to the cells and induced significantly higher cytotoxicity compared to nonreleased encapsulated drug. Our findings show promise for targeted drug delivery using this theranostic delivery platform at low US intensities.

[Is initial success after Monarc(®) suburethral sling durable at mid-term evaluation?]. / Le succès thérapeutique après bandelette Monarc(®) est-il durable à moyen terme ?

OBJECTIVES: Suburethral sling is the gold standard treatment for stress urinary incontinence (SUI). Short-term cure rates are high, but only few studies are available for longer assessment after transobturator tape procedure. The objectives of this study were to assess mid-term functional outcome for Monarc(®) transobturator tape after initial success, and to identify risk factors for recurrence. MATERIAL AND METHODS: We conducted a single centre retrospective study (2004-2013) on consecutive women with SUI who underwent Monarc(®) transobturator tape procedure and were initially cured at the postoperative medical consultation. Pre- and postoperative data (age, weight, height, body mass index, hormonal status, surgical history, associated organ prolapse [Baden and Walker], associated urinary symptoms, postoperative complications [Clavien-Dindo]) were extracted from the electronic medical record. Subjective cure was defined by a score of zero from the ICIQ-SF questionnaire, no second intervention for recurrent SUI and no need for pads at latest news. Statistical analysis was performed using SAS(®) v9.3 (P<0.05). RESULTS: One hundred and thirty-three consecutive women underwent TOT Monarc(®) procedure, and 125 women were cured in the short-term. Among these women, 103 (82%) were available for mid-term evaluation. Sixty-four women (62%) had pure stress urinary incontinence. The mean follow-up period was 51 months [2-119]. At last follow-up, cure rate was 61%. Seventy-eight percent of women with recurrent urinary incontinence had SUI. Other women had mixed urinary incontinence (3/40), or de novo urgency (6/40). In univariate analysis, we could not identify pejorative prognostic factors for mid-term failure. CONCLUSION: In our experience, mid-term functional outcome after Monarc(®) transobturator tape procedure seems to deteriorate. After 4 years of follow-up, 61% of the women who were initially cured were still free from any leakage. LEVEL OF EVIDENCE: 4.

[Prognostic factors for severe infection after flexible ureteroscopy: Clinical interest of urine culture the day before surgery?]. / Facteurs favorisants les infections sévères après urétéroscopie souple : intérêt de l'ECBU systématique la veille de l'intervention.

OBJECTIVES: The objectives of this study have been to determine prognostic factors for acute pyelonephritis (AP) after flexible ureteroscopy (FU), to assess the frequency of readmission for AP and to study the usefulness of urinalysis the day before surgery. METHODS: Between 2010 and 2013, 266 patients have had at least one ureteroscopy (n=325). All infectious complications and unplanned readmissions within the month after FU were retrospectively evaluated. Several data have been collected: age, sex, BMI, surgical indication (calculis or tumor), number of previous ureteroscopies, number of previous surgeries for calculis, stones number, size and location, bilateral interventions, operating time, preoperative ureteral stenting, postoperative stenting, hospitalization stay, urine culture the day before surgery (j-1) and prescription of antibiotic therapy the week before FU. Correlation between these variables and acute pyelonephritis (AP) the month following the USSR was tested (StatView 4.5, SAS Institute) (P<0.05 significant). RESULTS: We observed 24 postoperative APs (7.4%), 17 prior to hospital discharge and 7 requiring rehospitalization. In univariate analysis, the significant prognostic factors of postoperative AP have been: stone size (>14 mm) (P=0.03); operating time (70 minutes) (P<0.005); positive day - 1 urine culture (P<0.001); antibiotics treatment the week before FU (P<0.001). In multivariate analysis, antibiotics prescription during the week before USSR remained significant (P<0.002; RR 5.8 [1.9-15]). CONCLUSION: Acute pyelonephritis requiring unplanned admission after ureteroscopy is a rare complication (2.4%). Urinalysis one day before ureteroscopy could allow early antibiotic therapy and may reduce 63% of unplanned hospital admissions for acute pyelonephritis. LEVEL OF EVIDENCE: 5.

Oversized cups as a major risk factor of postoperative pain after total hip arthroplasty.

After total hip arthroplasty (THA) some patients have persistent postoperative pain (POP). Some of these POP are anterior and are caused by an anterior iliopsoas impingement (AIPI). We have hypothesized that oversized implanted cups could be responsible for POP and especially AIPI. We screened 237 patients who had a primary THA and compared the size difference (ΔS) between the native femoral head and the implanted cup, in patients with and without POP. Median ΔS was 2 mm [-6; 11 mm] and patients with POP had a significantly increased ΔS (P < 0.0001). The threshold above which pain was significantly more frequent was ΔS ≥ 6 mm. Odds ratio was 14.4 for POP and 26 for AIPI pain when ΔS ≥ 6 mm.

[Screening of prostate cancer seen by general practitioners]. / Le dépistage du cancer de la prostate vu par les médecins généralistes.

INTRODUCTION: The screening of prostate cancer was recently the subject of international studies and debates in France. We decided to study the vision of the screening, in particular by the PSA, which have the general practitioners. METHODS: We sent a questionnaire to 456 general practitioners of Oise (French department) to be returned in an anonymous way on the prostate cancer, PSA, the economic impact of the PSA and we asked whether the doctors realized the screening or not, if they were favorable to it and for which reasons. RESULTS: We received 38% of answers. Eighty-one percent of the general practitioners considered that prostate cancer is frequent, 72% that it evolved slowly and 55% that it affected old men. For 79% of the general practitioners, the patients were asking for a screening by PSA. Eighty-eight percent thought that they had to be in front line of the screening, 58% that the functional consequences of the screening were satisfactory. Fifty-seven percent of the general practitioners realized the screening in a systematic way and 88% were favorable to it. CONCLUSION: The general practitioners of Oise remained favorable for the greater part to the screening of prostate cancer and the patients applicants in spite of various debates.

Dynamic Behavior of Polymer Microbubbles During Long Ultrasound Tone-Burst Excitation and Its Application for Sonoreperfusion Therapy.

OBJECTIVE: Ultrasound (US)-targeted microbubble (MB) cavitation (UTMC)-mediated therapies have been found to restore perfusion and enhance drug/gene delivery. Because of the potentially longer circulation time and relative ease of storage and reconstitution of polymer-shelled MBs compared with lipid MBs, we investigated the dynamic behavior of polymer microbubbles and their therapeutic potential for sonoreperfusion (SRP) therapy. METHODS: The fate of polymer MBs during a single long tone-burst exposure (1 MHz, 5 ms) at various acoustic pressures and MB concentrations was recorded via high-speed microscopy and passive cavitation detection (PCD). SRP efficacy of the polymer MBs was investigated in an in vitro flow system and compared with that of lipid MBs. DISCUSSION: Microscopy videos indicated that polymer MBs formed gas-filled clusters that continued to oscillate, fragment and form new gas-filled clusters during the single US burst. PCD confirmed continued acoustic activity throughout the 5-ms US excitation. SRP efficacy with polymer MBs increased with pulse duration and acoustic pressure similarly to that with lipid MBs but no significant differences were found between polymer and lipid MBs. CONCLUSION: These data suggest that persistent cavitation activity from polymer MBs during long tone-burst US excitation confers excellent reperfusion efficacy.

Effect of Ultrasound Pulse Length on Sonoreperfusion Therapy.

In recent years, long- and short-pulse ultrasound (US)-targeted microbubble cavitation (UTMC) has been found to increase perfusion in healthy and ischemic skeletal muscle, in pre-clinical animal models of microvascular obstruction and in the myocardium of patients presenting with acute myocardial infarction. There is evidence that the observed microvascular vasodilation is driven by the nitric oxide pathway and purinergic signaling, but the time course of the response and the dependency on US pulse length are not well elucidated. Because our prior data supported that sonoreperfusion efficacy is enhanced by long-pulse US versus short-pulse US, in this study, we sought to compare long-pulse (5000 cycles) and short-pulse (500 × 10 cycles) US at a pressure of 1.5 MPa with an equivalent total number of acoustical cycles, hence constant acoustic energy, and at the same frequency (1 MHz), in a rodent hind limb model with and without microvascular obstruction (MVO). In quantifying perfusion using burst replenishment contrast-enhanced US imaging, we made three findings: (i) Long and short pulses result in different vasodilation kinetics in an intact hind limb model. The long pulse causes an initial spasmic reduction in flow that spontaneously resolved at 4 min, followed by sustained higher flow rates (approximately twofold) compared with baseline, starting 10 min after therapy (p < 0.05). The short pulse caused a short-lived approximately twofold increase in flow rate that peaked at 4 min (p < 0.05), but without the initial spasm. (ii) The sustained increased response with the long pulse is not simply reactive hyperemia. (iii) Both pulses are effective in reperfusion of MVO in our hindlimb model by restoring blood volume, but only the long pulse caused an increase in flow rate after treatment ii, compared with MVO (p < 0.05). Histological analysis of hind limb muscle post-UTMC with either pulse configuration indicates no evidence of tissue damage or hemorrhage. Our findings indicate that the microbubble oscillation induces vasodilation, and therapeutic efficacy for the treatment of MVO can be tuned by varying pulse length; relative to short-pulse US, longer pulses drive greater microbubble cavitation and more rapid microvascular flow rate restoration after MVO, warranting further optimization of the pulse length for sonoreperfusion therapy.

[Evolution of prostatic surgical interventions: analysis of French national coding database]. / Évolution de la prise en charge chirurgicale des pathologies prostatiques : analyse nationale du codage.

INTRODUCTION: Prostatic diseases are very important in urologist's practice. We wanted to study evolution of prostatic procedures using French national coding database. METHODS: We searched the Agence Technique d'Information sur l'Hospitalisation (ATIH) web server for prostatic procedures between 1997 and 2011 for both private and public sectors. RESULTS: The procedures were more often performed in private sector (up to 70%). There was a sustained increase (+332%) of the number of prostatectomies between 1997 and 2007 (more than 27,000 procedures), followed by a slight decrease. There is a rising use of laparoscopic approach from 35% in 2006 up to 58% in 2011. The use of brachytherapy and HIFU was marginal. Transurethral resection of the prostate number was stable between 56,000 and 60,000 procedures a year (for cancer for less than 7%). Adenomectomies number decreased from 9832 to 7963 procedures a year. CONCLUSION: The most noticeable data were upon prostatectomies number, with a peak effect in 2007. Laparoscopic procedures were more and more frequent. TURP number was stable, whereas adenomectomies number decreased.

The chemical dynamics of nanosensors capable of single-molecule detection.

Recent advances in nanotechnology have produced the first sensor transducers capable of resolving the adsorption and desorption of single molecules. Examples include near infrared fluorescent single-walled carbon nanotubes that report single-molecule binding via stochastic quenching. A central question for the theory of such sensors is how to analyze stochastic adsorption events and extract the local concentration or flux of the analyte near the sensor. In this work, we compare algorithms of varying complexity for accomplishing this by first constructing a kinetic Monte Carlo model of molecular binding and unbinding to the sensor substrate and simulating the dynamics over wide ranges of forward and reverse rate constants. Methods involving single-site probability calculations, first and second moment analysis, and birth-and-death population modeling are compared for their accuracy in reconstructing model parameters in the presence and absence of noise over a large dynamic range. Overall, birth-and-death population modeling was the most robust in recovering the forward rate constants, with the first and second order moment analysis very efficient when the forward rate is large (>10(-3) s(-1)). The precision decreases with increasing noise, which we show masks the existence of underlying states. Precision is also diminished with very large forward rate constants, since the sensor surface quickly and persistently saturates.

12-month mortality and loss-to-program in antiretroviral-treated children: The IeDEA pediatric West African Database to evaluate AIDS (pWADA), 2000-2008.

BACKGROUND: The IeDEA West Africa Pediatric Working Group (pWADA) was established in January 2007 to study the care and treatment of HIV-infected children in this region. We describe here the characteristics at antiretroviral treatment (ART) initiation and study the 12-month mortality and loss-to-program of HIV-infected children followed in ART programs in West Africa. METHODS: Standardized data from HIV-infected children followed-up in ART programs were included. Nine clinical centers from six countries contributed to the dataset (Benin, Côte d'Ivoire, Gambia, Ghana, Mali and Senegal). Inclusion criteria were the followings: age 0-15 years and initiated triple antiretroviral drug regimens. Baseline time was the date of ART initiation. WHO criteria was used to define severe immunosuppression based on CD4 count by age or CD4 percent < 15%. We estimated the 12-month Kaplan-Meier probabilities of mortality and loss-to-program (death or loss to follow-up > 6 months) after ART initiation and factors associated with these two outcomes. RESULTS: Between June 2000 and December 2007, 2170 children were included. Characteristics at ART initiation were the following: median age of 5 years (Interquartile range (IQR: 2-9) and median CD4 percentage of 13% (IQR: 7-19). The most frequent drug regimen consisted of two nucleoside reverse transcriptase inhibitors and one non-nucleoside reverse transcriptase inhibitors (62%). During the first 12 months, 169 (7.8%) children died and 461(21.2%) were lost-to-program. Overall, in HIV-infected children on ART, the 12-month probability of death was 8.3% (95% Confidence Interval (CI): 7.2-9.6%), and of loss-to-program was 23.1% (95% CI: 21.3-25.0%). Both mortality and loss-to program were associated with advanced clinical stage, CD4 percentage < 15% at ART initiation and year (> 2005) of ART initiation. CONCLUSION: Innovative and sustainable approaches are needed to better document causes of death and increase retention in HIV pediatric clinics in West Africa.

Ultrasound characterization of red blood cell aggregation with intervening attenuating tissue-mimicking phantoms.

The analysis of the ultrasonic frequency-dependent backscatter coefficient of aggregating red blood cells reveals information about blood structural properties. The difficulty in applying this technique in vivo is due to the frequency-dependent attenuation caused by intervening tissue layers that distorts the spectral content of signals backscattered by blood. An optimization method is proposed to simultaneously estimate tissue attenuation and blood structure properties, and was termed the structure factor size and attenuation estimator (SFSAE). An ultrasound scanner equipped with a wide-band 25 MHz probe was used to insonify porcine blood sheared in both Couette and tubular flow devices. Since skin is one of the most attenuating tissue layers during in vivo scanning, four skin-mimicking phantoms with different attenuation coefficients were introduced between the transducer and the blood flow. The SFSAE gave estimates with relative errors below 25% for attenuations between 0.115 and 0.411 dBMHz and kR<2.08 (k being the wave number and R the aggregate radius). The SFSAE can be useful to examine in vivo and in situ abnormal blood conditions suspected to promote pathophysiological cardiovascular consequences.

The effect of ultrasound pulse length on microbubble cavitation induced antibody accumulation and distribution in a mouse model of breast cancer.

In solid tumors, the limited diffusion of therapeutic molecules in the perivascular space is a known limitation impacting treatment efficacy. Ultrasound Targeted Microbubble Cavitation (UTMC) has been shown to increase vascular permeability and improve the delivery of therapeutic compounds including small molecules, antibodies (mAb), nanoparticles and even cells, notably across the blood-brain-barrier (BBB). In this study, we hypothesized that UTMC could improve the accumulation and biodistribution of mAb targeting the adenosinergic pathway (i.e. CD73) in mice bearing bilateral subcutaneous 4T1 mammary carcinoma. METHODS: A bolus of fluorescently labeled mAb was given intravenously, followed by a slow infusion of microbubbles. UTMC therapy (1 MHz, 850 kPa) was given under ultrasound image guidance for 5 minutes to the right side tumor only, using three different pulse lengths with identical ultrasound energy (5000cyc "long", 125x40cyc "mid" and 500x10cyc "short"), and leaving the left tumor as a paired control. Longitudinal accumulation at 0 h, 4 h and 24 h was measured using whole-body biofluorescence and confocal microscopy. RESULTS: Our data support an increase in antibody accumulation and extravasation (# extravasated vessels and extravasated signal intensity) at 0 h for all pulses and at 4 h for the mid and short pulses when compared to the control non treated side. However, this difference was not found at 24 h post UTMC, indicative of the transient nature of UTMC. Interestingly, confocal data supported that the highest extravasation range was obtained at 0 h with the long pulse and that the short pulse caused no increase in the extravasation range. Overall, the mid pulse was the only pulse to increase all our metrics (biofluorescence, fraction of extravasated vessels, amount of extravasated Ab, and extravasation range) at 0 h and 4 h time points. CONCLUSIONS: Our results support that UTMC can enhance antibody accumulation in solid tumors at the macroscopic and microscopic levels. This preferential accumulation was evident at early time points (0 h and 4 h) but had started to fade by 24 h, a time dependence that is consistent with the ultrasound blood brain barrier opening literature. Further development and optimization of this theranostic platform, such as repeated UTMC, could help improve antibody based therapies against solid cancer.

Sonoreperfusion therapy for microvascular obstruction: A step toward clinical translation.

Sonoreperfusion therapy is being developed as an intervention for the treatment of microvascular obstruction. We investigated the reperfusion efficacy of two clinical ultrasound systems (a modified Philips EPIQ and a Philips Sonos 7500) in a rat hindlimb microvascular obstruction model. Four ultrasound conditions were tested using 20 min treatments: Sonos single frame, Sonos multi-frame, EPIQ low pressure and EPIQ high pressure. Contrast-enhanced perfusion imaging of the microvasculature was conducted at baseline and after treatment to calculate microvascular blood volume (MBV). EPIQ high pressure treatment resulted in significant recovery of MBV from microvascular obstruction, returning to baseline levels after treatment. EPIQ low pressure and Sonos multi-frame treatment resulted in significantly improved MBV after treatment but below baseline levels. Sonos single-frame and control groups showed no improvement post-treatment. This study demonstrates that the most effective sonoreperfusion therapy occurs at high acoustic pressure coupled with high acoustic intensity. Moreover, a clinically available ultrasound system is readily capable of delivering these effective therapeutic pulses.

Assisted HIV partner services training in three sub-Saharan African countries: facilitators and barriers to sustainable approaches.

INTRODUCTION: Healthcare worker training is essential to successful implementation of assisted partner services (aPS), which aims to improve HIV testing and linkage-to-care outcomes for previously unidentified HIV-positive individuals. Cameroon, Kenya and Mozambique are three African countries that have implemented aPS programmes and are working to bring those programmes to scale. In this paper, we present and compare different aPS training strategies implemented by these three countries, and discuss facilitators and barriers associated with implementation of aPS training in sub-Saharan Africa. DISCUSSION: aPS training programmes in Cameroon, Kenya and Mozambique share the following components: the development of comprehensive and interactive training curricula, recruitment of qualified trainees and trainers with intimate knowledge of the community served, continuous training, and rigorous monitoring and evaluation activities. Cameroon and Kenya were able to engage various stakeholders early on, establishing multilateral coalitions that facilitated attainment of long-term buy-in from the local governments. Ministries of Health and various implementing partners are often included in strategic planning and delivery of training curricula to ensure sustainability of the training programmes. Kenya and Mozambique have integrated aPS training into the national HTS guidelines, which are being rolled out nationwide by the Ministries of Health and implementing partners. Continual revision of training curricula to reflect the country context, as well as ongoing monitoring and evaluation, have also been identified as key facilitators to sustain aPS training programmes. Some of the barriers to scale-up and sustainability of aPS training include limited funding and resources for training and scale-up and shortage of aPS providers to facilitate on-the-job mentorship. CONCLUSIONS: These three programmes demonstrate that aPS training can be implemented and scaled up in sub-Saharan Africa. As countries plan for initial implementation or national scale-up of aPS services, they will need to establish government buy-in, expand funding sources, address the shortage of staff and resources to provide aPS and on-the-job mentorship, and continuously collect data to evaluate and improve aPS training plans. Development of national standards for aPS training, empowered healthcare providers, increased government commitment, and sustained funding for aPS services and training will be crucial for successful aPS implementation.