Sexual and reproductive health services for people living with HIV: a systematic review

People living with HIV often have unmet needs for sexual and reproductive health (SRH) services. We present results of a systematic review of studies offering SRH services targeted to people living with HIV. Studies were selected from a broader SRH and HIV linkages review. Inclusion criteria included: (1) peer-reviewed journal articles with a pre-post or multiple-arm study design; (2) reported post-intervention evaluation data; and (3) published 1 January 1990 through 31 December 2007. Nine studies were identified with an average rigour score of 5.1 out of 9. Services included family planning (one study), sexually transmitted infection (STI) services (two studies), combined family planning and STI services (three studies) and multiple services (three studies). The review identified mostly positive effects on the outcomes measured, including condom and contraceptive use and quality of services. Yet gaps remain in the research to establish the best approaches for addressing needs and choices of people living with HIV. There is a need for high-quality intervention studies to determine the most successful and cost-effective strategies for providing SRH services to people living with HIV.     

Outer volume suppression in steady state sequences (OVSuSS) for percutaneous interventions

Magnetic resonance‐guided percutaneous interventions with needles require fast pulse sequences with acquisition times less than 1 s to image the needle trajectory within moving organs. To guide the movement of a rigid instrument with high sampling rate, an magnetic resonance imaging method was developed that reduces the acquisition time down to a few hundred milliseconds by restricting the field of view to a small stripe around the instrument trajectory. To maintain the dynamic steady state, saturation pulses for outer volume suppression were inserted into additional repetition time‐intervals. These saturation intervals were combined with three sequence variants: a spoiled gradient echo sequence, an echo‐shifted steady state free precession and a balanced steady state free precession sequence. The magnetization dynamics were analyzed by means of numerical optimized simulations. Results were compared with phantom experiments and an average signal‐to‐suppression‐ratio of 15.5 could be achieved. With a field of view reduction of up to 12.5% an update rate of six images per second could be achieved. Finally, animal experiments demonstrated the fast and reliable needle tip visualization during percutaneous magnetic resonance‐guided interventions with the help of a robotic assistance system. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.     

Noninvasive Cardiac Output Measurement at Rest and During Exercise in Pediatric Patients After Interventional or Surgical Atrial Septal Defect Closure

In the majority of patients, secundum atrial septal defects (ASDs) are treated interventionally or surgically, before the onset of clinical symptoms, between 3 and 6?years of age. Because right-ventricular dimensions usually normalize after ASD closure, it has been assumed that cardiac function and exercise performance also normalize at long-term follow-up. The aim of our study was to determine cardiac index (CI) at rest and during exercise at medium-term follow-up of children who had undergone surgical or interventional closure of ASD because no such reports have been published thus far. Seventeen patients (age range 8.8-17.3?years) who underwent surgical correction were included together with 17 subjects who received an interventional procedure with Amplatzer and Helex occluders (age range 12.2-17.3?years). The study was performed after a median interval of 8.6?years (range 6.5-11.6) after the procedure. Twelve healthy children of comparable age served as controls. CI measurements were performed based on the inert gas-rebreathing method with the Innocor system. For exercise testing, the standard treadmill protocol of the German Society of Pediatric Cardiology was used. CI, stroke volume (SV), and heart rate (HR) were determined at rest and at two standardized submaximal exercise levels (levels 3 and 6). CI increased in all subjects under exercise conditions. Neither SV nor HR displayed significant differences between the three groups either at rest or under exercise conditions. Although HR increased continuously, no increase of indexed SV occurred beyond level 3. Noninvasive determination of CI at rest and during exercise with the IGR method is feasible in the pediatric age group. At medium-term follow-up, we found no significant differences between patients who underwent surgical or interventional ASD closure compared with normal controls.     

BioShuttle mobility in living cells studied with high-resolution FCS & CLSM methodologies

With the increase in molecular diagnostics and patient-specific therapeutic approaches, the delivery and targeting of imaging molecules and pharmacologically active agents gain increasing importance. The ideal delivery system does not exist yet. The realization of two features is indispensable: first, a locally high concentration of target-specific diagnostic and therapeutic molecules; second, the broad development of effective and safe carrier systems. Here we characterize the transport properties of the peptide-based BioShuttle transporter using FFM and CLSM methods. The modular design of BioShuttle-based formulations results in a multi-faceted field of applications, also as a theranostic tool.     

Cilengitide inhibits progression of experimental breast cancer bone metastases as imaged noninvasively using VCT,MRI and DCE‐MRI in a longitudinal in vivo study

The aim of this study was to investigate the effect of inhibiting α_vβ₃/α_vβ₅ integrins by cilengitide in experimentally induced breast cancer bone metastases using noninvasive imaging techniques. For this purpose, nude rats bearing established breast cancer bone metastases were treated with cilengitide, a small molecule inhibitor of α_vβ₃ and α_vβ₅ integrins (75 mg/kg, five days per week; n = 12 rats) and compared to vehicle‐treated control rats (n = 12). In a longitudinal study, conventional magnetic resonance imaging (MRI) and flat panel volumetric computed tomography were used to assess the volume of the soft tissue tumor and osteolysis, respectively, and dynamic contrast‐enhanced (DCE‐) MRI was performed to determine functional parameters of the tumor vasculature reflecting blood volume and blood vessel permeability. In rats treated with cilengitide, VCT and MRI showed that osteolytic lesions and the respective bone metastatic soft tissue tumors progressed more slowly than in vehicle‐treated controls. DCE‐MRI indicated a decrease in blood volume and an increase in vessel permeability and immunohistology revealed increased numbers of immature vessels in cilengitide‐treated rats compared to vehicle controls. In conclusion, treatment of experimental breast cancer bone metastases with cilengitide resulted in pronounced antiresorptive and antitumor effects, suggesting that α_vβ₃/α_vβ₅ inhibition may be a promising therapeutic approach for bone metastases.     

An expandable catheter loop coil for intravascular MRI in larger blood vessels

The present study proposes a catheter system with an expandable coil etched on a polyimide foil. The catheter system combines the advantages of a small insertion diameter when the coil is rolled up in a protective carrier sheath with an increased signal‐to‐noise ratio (SNR) and penetration depth when the coil is pushed out. After imaging, the coil can be retracted into the sheath and folded back into the initial rolled‐up configuration due to the tapered geometry of the carrier foil. The catheter system was tested on two healthy anesthetized pigs, including tracking and high‐resolution intravascular imaging. To reduce artifacts in high‐resolution images induced by catheter motion in the pulsatile blood flow, a motion‐gating method was implemented that combines a flow‐compensated two‐dimensional fast low angle shot (FLASH) imaging sequence with the acquisition of projection data for retrospective gating. Using the projection data for motion detection, image SNR was increased by up to 500% over uncorrected images, and anatomic structures of 150 μm size could be differentiated in the aorta. Magn Reson Med, 2010. © 2009 Wiley‐Liss, Inc.     

Dual-bolus approach to quantitative measurement of pulmonary perfusion by contrast-enhanced MRI

PURPOSE: To evaluate a dual-bolus approach to pulmonary perfusion MRI. MATERIALS AND METHODS: The dual-bolus approach uses a separate low-dose measurement for the arterial input function (AIF) to ensure linearity. The measured AIF is constructed according to a subsequent higher dose used for the tissue concentration curves in the lung. In this study a prebolus of 0.01 mmol/kg followed by doses of 0.04 mmol/kg and 0.08 mmol/kg was used. Measurements were performed using time-resolved two-dimensional fast low-angle shot (2D FLASH) MRI (TE/TR = 0.73 msec/1.73 msec; flip angle = 40 degrees ; generalized autocalibrating partially parallel acquisitions (GRAPPA) factor = 3; temporal resolution = 400 msec) in end-inspiratory breath-hold. RESULTS: The combination of prebolus/0.04 mmol/kg resulted in a pulmonary blood flow (PBF) of 211 +/- 77 mL/min/100 mL, and a pulmonary blood volume (PBV) of 20 +/- 3 mL/100 mL. The combination of prebolus/0.08 mmol/kg resulted in approximately 50% lower perfusion values, most likely due to saturation effects in the lung tissue. CONCLUSION: A dual-bolus approach to pulmonary perfusion MRI is feasible and may reduce the problem of lacking linear relationship between the contrast-agent concentration and signal intensity.     

Sodium MRI using a density‐adapted 3D radial acquisition technique

A density‐adapted three‐dimensional radial projection reconstruction pulse sequence is presented which provides a more efficient k‐space sampling than conventional three‐dimensional projection reconstruction sequences. The gradients of the density‐adapted three‐dimensional radial projection reconstruction pulse sequence are designed such that the averaged sampling density in each spherical shell of k‐space is constant. Due to hardware restrictions, an inner sphere of k‐space is sampled without density adaption. This approach benefits from both the straightforward handling of conventional three‐dimensional projection reconstruction sequence trajectories and an enhanced signal‐to‐noise ratio (SNR) efficiency akin to the commonly used three‐dimensional twisted projection imaging trajectories. Benefits for low SNR applications, when compared to conventional three‐dimensional projection reconstruction sequences, are demonstrated with the example of sodium imaging. In simulations of the point‐spread function, the SNR of small objects is increased by a factor 1.66 for the density‐adapted three‐dimensional radial projection reconstruction pulse sequence sequence. Using analytical and experimental phantoms, it is shown that the density‐adapted three‐dimensional radial projection reconstruction pulse sequence allows higher resolutions and is more robust in the presence of field inhomogeneities. High‐quality in vivo images of the healthy human leg muscle and the healthy human brain are acquired. For equivalent scan times, the SNR is up to a factor of 1.8 higher and anatomic details are better resolved using density‐adapted three‐dimensional radial projection reconstruction pulse sequence. Magn Reson Med, 2009. © 2009 Wiley‐Liss, Inc.     

Imaging response to systemic therapy for bone metastases

In patients with osteotropic primary tumours such as breast and prostate cancer, imaging treatment response of bone metastases is essential for the clinical management. After treatment of skeletal metastases, morphological changes, in particular of bone structure, occur relatively late and are difficult to quantify using conventional X-rays, CT or MRI. Early treatment response in these lesions can be assessed from functional imaging techniques such as dynamic contrast-enhanced techniques by MRI or CT and by diffusion-weighted MRI, which are quantifiable. Among the techniques within nuclear medicine, PET offers the acquisition of quantifiable parameters for response evaluation. PET, therefore, especially in combination with CT and MRI using hybrid techniques, holds great promise for early and quantifiable assessment of treatment response in bone metastases. This review summarises the classification systems and the use of imaging techniques for evaluation of treatment response and suggests parameters for the early detection and quantification of response to systemic therapy.