Acute study of dose-dependent effects of (-)-epicatechin on vascular function in healthy male volunteers: A randomized controlled trial

BACKGROUND & AIMS

There is convincing clinical evidence to suggest that flavanol-containing foods/beverages are capable of inducing improvements in human vascular function. However, whilst (-)-epicatechin has been tested for efficacy, a full dose-dependency has yet to be established, particularly at doses below 1 mg/kg BW. The current study examined the dose-dependent effects of (-)-epicatechin on human vascular function with concurrent measurement of plasma (-)-epicatechin metabolites and levels of circulating nitrite and nitrate species, NO_x.

METHODS

An acute, double-blind, placebo-controlled, crossover intervention trial was conducted in 20 healthy males with 4 treatment arms: water-based (-)-epicatechin (0.1, 0.5 and 1.0 mg/kg BW) and a water only as control. Vascular function was assessed by flow-mediated dilatation (FMD) measured at the brachial artery, laser Doppler imaging with iontophoresis (LDI) at the subcutaneous capillaries of the forearm (response to Ach and SNP) and peripheral blood pressure (BP) at baseline, 1, 2, 4 and 6 h post-intervention. Plasma analysis of epicatechin metabolites was conducted by LC-MS and circulating plasma of nitrite and nitrate species were performed using an HPLC-based system (ENO-30).

RESULTS

Significant increases in % FMD were found to occur at 1 and 2 h following intake of 1 mg/kg BW, and at 2 h for the 0.5 mg/kg BW intake. There were no significant changes in LDI or BP at any time-points or intake levels. Increases in FMD over the 6 h timeframe were closely paralleled by the appearance of total plasma (-)-epicatechin metabolites. Non-significant changes in circulating NOx was observed.

CONCLUSIONS

Our data add further evidence that (-)-epicatechin is a causal vasoactive molecule within flavanol-containing foods/beverages. In addition, we show for the first time that intake levels as low as 0.5 mg/kg BW are capable of inducing acute improvements in vascular function (FMD) in healthy volunteers.

Safety and efficacy of a new device for inducing ejaculation in men with spinal cord injuries

STUDY DESIGN

Prospective case series.

OBJECTIVES

Male infertility is a common sequela of spinal cord injury (SCI). Fatherhood is a goal in this group of young patients; however, most are anejaculatory. Penile vibratory stimulation is recommended as the first line of treatment for this condition. Our study evaluated the safety and efficacy of a new device designed to induce ejaculation in these patients.

SETTING

The Miami Project to Cure Paralysis, Miami, FL, USA.

METHODS

The Viberect-X3 (Reflexonic, Frederick, MD, USA) was applied to 30 consecutive anejaculatory men with SCI whose level of injury was T10 and rostral.

RESULTS

The ejaculatory success was 77% (23/30). No adverse events occurred, and there were no malfunctions of the device.

CONCLUSION

In this first report on the efficacy of the Viberect-X3 for treatment of anejaculation in men with SCI, we conclude that the device is safe and effective for inducing ejaculation in men with SCI. Recommendation of the Viberect-X3 versus other devices intended for this purpose should not be made until randomized controlled trials are performed.

Neutralization of ASC improves sperm motility in men with spinal cord injury

STUDY QUESTION

Does neutralization of apoptosis-associated speck-like protein containing a caspase activation and recruitment domain (ASC) improve sperm motility in men with spinal cord injury (SCI)?

SUMMARY ANSWER

Neutralization of ASC improves sperm motility in men with SCI.

WHAT IS KNOWN ALREADY

Semen of men with SCI contains normal sperm concentrations but abnormally low sperm motility. Inflammatory cytokines, activated via the inflammasome complex, are contributory. A key component of the inflammasome is ASC.

STUDY DESIGN, SIZE, DURATION

This prospective study included semen samples collected from 32 men with SCI.

PARTICIPANTS/MATERIALS, SETTING, METHODS

At a major university medical center, untreated semen was compared with semen treated with anti-ASC polyclonal antibody. Semen treated with IgG was used as a control.

MAIN RESULTS AND THE ROLE OF CHANCE

Addition of anti-ASC polyclonal antibody to semen significantly increased mean sperm motility from 11.5% (95% CI, 6.3-16.7) to 18.3% (95% CI, 11.8-24.8). Improvements were most pronounced in the subgroup whose starting motility ranged between 6 and 40%. In this subgroup, the mean sperm motility improved from 13.3% (95% CI, 9.3-17.3) to 23.9% (95% CI, 14.7-23.0). Sperm motility did not improve after treatment with IgG.

LIMITATIONS, REASONS FOR CAUTION

This study is limited by the small sample size as this is a rare population.

WIDER IMPLICATIONS OF THE FINDINGS

Blockade of the inflammasome via treatment with anti-ASC improved sperm motility in men with SCI. In doing so, this treatment significantly increased their total motile sperm count. This is the first study to demonstrate that interference with the inflammasome improves sperm motility in men with SCI. This treatment has potential as a therapeutic intervention.

STUDY FUNDING/COMPETING INTERESTS

This study was funded by the Craig H. Neilsen Foundation, Grant # 224598, the University of Miami Miller School of Medicine and the Miami Project to Cure Paralysis, Miami, FL, USA. R.W.K. and J.P.d.R.V. hold a patent for the treatment of inflammation after central nervous system injury using antibodies against inflammasome proteins. The other authors have no conflicts of interest to declare.

Radio-frequency ablation helps preserve nephrons in salvage of failed microwave ablation for a renal cancer in a solitary kidney

Recurrent tumors after renal ablative therapy present a challenge for clinicians. New ablative modalities, including microwave ablation (MWA), have very limited experience in methods of retreating ablation failures. Additionally, in MWA, no long-term outcomes have been reported. In patients having local tumor recurrence, options for surveillance or surgical salvage must be assessed. We present a case to help assess radio-frequency ablation (RFA) for salvage of failed MWA. We report a 63-year-old male with a 4.33-cm renal mass in a solitary kidney undergoing laparoscopic MWA with simultaneous peripheral fiber-optic thermometry (Lumasense, Santa Clara, CA, USA) as primary treatment. Follow-up contrast-enhanced computed tomography (CT) scan was performed at 1 and 4.3 months post-op with failure occurring at 4.3 months as evidenced by persistent enhancement. Subsequently, a laparoscopic RFA (LRFA) with simultaneous peripheral fiber-optic thermometry was performed as salvage therapy. Clinical and radiological follow-up with a contrast-enhanced CT scan at 1 and 11 months post-RFA showed no evidence of disease or enhancement. Creatinine values pre-MWA, post-MWA, and post-RFA were 1.01, 1.14, and 1.17 mg/ml, respectively. This represents a 15% decrease in estimated glomerular filtration rate (eGFR) (79 to 67 ml/min) post-MWA and no change in eGFR post-RFA. Local kidney tumor recurrence often requires additional therapy and a careful decisionmaking process. It is desirable not only to preserve kidney function in patients with a solitary kidney or chronic renal insufficiency, but also to achieve cancer control. We show the feasibility of RFA for salvage treatment of local recurrence of a T1b tumor in a solitary kidney post-MWA.

Renal volumetric analysis: a new paradigm in renal mass treatment assessment

Abstract Background and Purpose: Multiple renal volumetric assessment studies have correlated parenchymal volume with the glomerular filtration rate. The objective of this study was to compare renal volumes before and after treatment of renal masses with either partial nephrectomy or radiofrequency ablation (RFA).

PATIENTS AND METHODS

We reviewed our prospectively collected database of patients with renal masses who were treated between November 2001 and January 2011 with robot-assisted laparoscopic partial nephrectomy (RALPN), laparoscopic RFA (LRFA), or CT-guided percutaneous RFA (CTRFA). Digital Imaging and Communications in Medicine CT imaging data were analyzed in an open-source viewer. Volumetric calculations were used to measure the normal, enhancing bilateral renal parenchyma and tumor volumes. Normal parenchymal volume loss was compared among treatments.

RESULTS

There were 96 patients (68 men) with an average age of 68.0 (36-84) years who met our inclusion criteria. The average tumor diameter, tumor volume, and nephrometry score (NS) was 3.5 cm, 32.0 cm(3), and 7.1 in RALPN (n=26), 2.6 cm, 9.8 cm(3), and 7.1 in CTRFA (n=47), and 2.9 cm, 14.3 cm(3), and 7.2 in LRFA (n=23) groups. The percent change in the operated kidney volume was similar in RALPN (-12%±15), CTRFA (-13%±16), and LRFA (-17%±18) groups. NS was the only variable in a multivariate linear regression model that correlated with the amount of volume lost in the ipsilateral kidney.

CONCLUSIONS

Our retrospective volumetric analysis of renal parenchyma before and after partial nephrectomy or RFA of renal masses revealed that all treatments produce similar volume of collateral damage.

Salvage robot-assisted partial nephrectomy for the management of renal cell carcinoma following failed stereotactic radiotherapy

With proper patient selection, this study suggests a robot-assisted laparoscopic approach may be utilized in the salvage management of renal tumors following failed stereotactic radiosurgery.

Nephron-sparing surgery is currently the standard of care for the management of small renal masses. While both neoadjuvant and adjuvant conventional external beam radiotherapy have failed to demonstrate an oncologic benefit for the treatment of renal cell carcinoma, more recent work aims to explore the utility of stereotactic radiotherapy. We present the case of a 70-year-old woman who failed primary treatment of a small renal mass with the CyberKnife radiotherapy system and describe her successful salvage treatment with robot-assisted partial nephrectomy. This case demonstrates the safety of robotic surgery for the management of renal tumors following failed stereotactic radiotherapy.

Application of "cinch/tie" technique to robotic-assisted nephropexy for posterior abdominal wall fixation

Nephropexy remains standard for symptomatic nephroptosis, and several minimally-invasive techniques have been described. Triangulation sutures placed between the abdominal wall and the renal capsule are often difficult to tie tightly due to the confined working space. We propose a technique modification to fixate the kidney utilizing the da Vinci Surgical System robot and Lapra-Ty absorbable suture clips. Four female patients with symptomatic nephroptosis diagnosed via kidney hypermobility demonstrated on intravenous urography (IVU) underwent robotic-assisted laparoscopic nephropexy (RALNP) from February 2008 to April 2010. After complete mobilization and stripping of perirenal fat, several 0 Vicryl sutures were placed in a "figure of eight" fashion and tied loosely. Subsequently we utilized a Lapra-Ty to tighten the stitch serially and fixate the kidney. The mean age was 46 years (43-52); one patient underwent simultaneous pyeloplasty and one underwent partial nephrectomy in the ipsilateral kidney. There were no intraoperative complications and two postoperative complications, both Clavien grade I. All patients were asymptomatic postoperatively at a mean follow-up of 9.2 months (1-28), and had no evidence of kidney hypermobility on upright IVU or diuretic renal scintigraphy (RS) scan at 6 weeks postoperatively. RALNP is a viable option in the treatment of symptomatic nephroptosis. Secure placement of several "pexing" sutures helps to ensure appropriate security of these itinerant kidneys. Our technique modification corrects kidney hypermobility while improving symptoms related to nephroptosis.

Cost comparison of nephron-sparing treatments for cT1a renal masses

OBJECTIVES

Treatment options for small renal tumors have evolved from radical nephrectomy (RN) to partial nephrectomy (PN), thermal ablation, or active surveillance. With the advancement of techniques, costs differences are unclear. The objective of this study is to compare the 6-month costs associated with nephron-sparing procedures for cT1a renal tumors.

MATERIALS AND METHODS

We performed a review of patients diagnosed with a solitary cT1a renal mass who underwent surgical treatment from June 2008 to May 2011. Open partial nephrectomy (OPN), robot-assisted partial nephrectomy (RLPN), laparoscopic radio-frequency ablation (LRFA), or computed tomography guided radio frequency ablation (CTRFA) was performed on 173 patients. Cost data were collected for surgical costs, associated hospital stay, and the 6-month postoperative period.

RESULTS

Patients underwent surgery, including 52 OPN, 48 RLPN, 44 LRFA, and 29 CTRFA. Median total costs associated were $17,018, $20,314, $13,965, and $6,475, for OPN, RLPN, LRFA, and CTRFA, respectively. When stratified by approach differences were noted for total cost (P < 0.001), operating room (OR) time (P < 0.001), surgical supply (P < 0.001), and room and board (P < 0.001) in univariable analysis. Multivariable linear regression (R(2) = 0.966) showed surgical approach (P = 0.007), length of stay (P < 0.001), and OR time (P < 0.001) to be significant predictors of total cost. However, tumor size (P = 0.175), and Charlson comorbidity index (P = 0.078) were not statistically significant.

CONCLUSIONS

Six-month cost of nephron-sparing surgery is lowest with radio frequency ablation (RFA) by either laparoscopic or computed tomography (CT)-guided approach compared to RLPN and OPN. As oncologic and safety outcomes improve and become comparable in all nephron-sparing surgery (NSS) approaches, cost of each procedure will start to play a stronger role in the clinical and healthcare policy setting.

Development and evaluation of a novel cadaveric model for performance of image-guided percutaneous renal tumor ablation

INTRODUCTION

Thermal ablation is a well established treatment option for the management small renal masses. Increasingly, renal ablation is performed via a percutaneous approach. However, most urologists are not formally trained in image-based deployment of ablation needles. To address this need, we created a novel training model to teach urologists to perform precise and accurate percutaneous needle placement. This teaching model was implemented as part of a recent training course on tissue ablation organized by the American Urological Association.

METHODS

Two fresh frozen human cadavers (Anatomic Gifts Registry, Hanover, Maryland) were used in the model. Plumber's Putty (Oatey, Cleveland, Ohio) and nonpitted olives soaked in Isovue (Bracco Dianostics, Inc, New York, New York) were used to create ablation targets. Course participants underwent a tutorial on the computed tomography (CT)-guided deployment of a 19-gauge Yueh Needle (Cook Medical, Bloomington, Indiana) or Cool-tip radio-frequency ablation (RFA) probe (Covidien, Inc, Boulder, Colorado). After each needle placement, a CT scan was performed to assess successful deployment. Participants were then queried regarding their experience.

RESULTS

A total of 18 urologists performed needle or radio-frequency ablation probe placement on 2 cadavers. A mean of 3.39 (range 2-5) attempts was required to hit targets. Subjectively, participants noted an increase in confidence performing percutaneous needle deployment. The cadaver laboratory exposed participants to pretreatment planning, tactile feel of needle placement, needle readjustment, and 3-D spatial relationships of a percutaneous approach.

CONCLUSIONS

The presented cadaveric model is an effective tool for teaching percutaneous needle placement. All urologists evaluated noted increased confidence in this technique after training on the model.

Radiofrequency ablation (RFA) therapy for renal angiomyolipoma (AML): an alternative to angio-embolization and nephron-sparing surgery

OBJECTIVES

To show that radiofrequency ablation (RFA) is safe and effective treatment for renal angiomyolipoma (AML). Current treatments to reduce the risk of haemorrhage include tumour extirpation, angio-embolization, or ablative therapy.

PATIENTS AND METHODS

Review of our prospective database revealed 15 patients with intraoperative biopsy confirmed renal AML undergoing RFA from February 2002 to March 2010. Patients underwent either laparoscopic or computed tomography (CT)-guided percutaneous RFA using either the Cool-tip™ (Covidien, Inc. Boulder, CO, USA) or RITA™ (Angiodynamics(®), Latham, NY, USA) RFA probe. CT at 1 month, 6 months, 1 year, and annually thereafter.

RESULTS

In all, two male and 13 female patients with seven left-sided and eight right-sided tumours with a mean (range) size of 2.6 (1.0-3.7) cm underwent laparoscopic (five) or CT-guided (10) RFA. No intraoperative complications occurred. Minor complications included transient haematuria and intercostals nerve transection. Surgical complications included pneumonia and myocardial infarction. There was no radiographic evidence of persistent AML (CT enhancement) at a mean follow-up of 21 months.

CONCLUSIONS

The haemostatic effect of RFA allows renal lesions suspicious for AML to be treated without bleeding complications. Avoids surgical risk of extirpation or embolization. RFA for renal AML is safe and effective.

Initial experience using microwave ablation therapy for renal tumor treatment: 18-month follow-up

OBJECTIVES

To assess efficacy and morbidity of microwave ablation (MWA) for small renal tumors in an initial cohort of patients. MWA is a recently introduced thermal needle ablation treatment modality with theoretical advantages compared with radiofrequency ablation, such as greater intratumoral temperatures, lack of a grounding pad, and superior convection profile. However, experience has been limited in the human kidney.

METHODS

Ten patients with a single, solid-enhancing renal tumor from June 2008 to November 2008 received laparoscopic or computed tomography-guided percutaneous MWA at a tertiary referral center with ≥14 months of follow-up. MWA was performed using the Valleylab Evident, 915-MHz MWA system at 45 W with intraoperative biopsy before ablation, and peripheral fiberoptic thermometry to determine the treatment endpoints. The patients were followed up with contrast-enhanced computed tomography at 1 month, 6 months to 1 year, and annually to monitor for tumor recurrence.

RESULTS

The follow-up duration for the 6 male and 4 female patients (mean tumor size 3.65 cm, range 2.0-5.5; mean age 69.8 years) was 17.9 months. The recurrence rate, defined by persistent enhancement, was 38% (3 of 8). The intraoperative and postoperative complication rate was 20% and 40%, respectively.

CONCLUSIONS

MWA resulted in poor oncologic outcomes with a significant complication rate at an intermediate level of follow-up. However, MWA has promising theoretical advantages and should not be discarded. Additional studies should be considered to better understand the microwave-tissue interaction and treatment endpoints for different size renal masses before widespread use.

Imaging and focal therapy in prostate and kidney cancer

The advancement of imaging modalities in the past two decades has led to the increased incidence of small renal masses. This same technology is making nephron-sparing treatment of small renal masses much more feasible and precise. The goal of this manuscript is to review the currently available imaging modalities utilized in focal treatment and follow-up of small renal masses.

Adequacy of a single 24-hour urine collection for metabolic evaluation of recurrent nephrolithiasis

PURPOSE

There is much debate about whether 1 or 2, 24-hour urinalyses are adequate for metabolic evaluation of stone formers. We determined whether repeat 24-hour urine collection provides information similar to that of the initial 24-hour urine collection and whether repeat collection is necessary.

MATERIALS AND METHODS

We analyzed 2, 24-hour urine collections in 777 patients obtained from 2001 to 2005. Samples were collected 3 days or less apart before pharmacological intervention and analyzed elsewhere for routine stone risk profiles of urine calcium, oxalate, citrate, uric acid, sodium, potassium, magnesium, phosphorus, ammonium, chloride, urea nitrogen and creatinine.

RESULTS

No parameters showed a statistically significant difference between 24-hour urine samples 1 and 2 when mean values were compared (pairwise t test each p >0.05, range 0.06 to 0.87). Using Pearson's correlation all parameters showed positive correlation coefficients (r = 0.68 to 0.89, each p <0.0001). The mean of individual patient differences in samples 1 and 2 were compared to 0 and 6 of 12 showed no difference (p >0.05) while for the remaining 6 p value was <0.05. The percent difference was 0.5% to 4.19% for all urinary parameters.

CONCLUSIONS

One 24-hour urine sample is sufficient for metabolic evaluation of recurrent stone disease. There is no significant difference in 12 urinary parameters between 24-hour urine samples collected within 3 days of each other. This information is useful to providers and may decrease patient inconvenience and the overall cost of metabolic stone evaluation.

Blockade of the renin-angiotensin system improves insulin sensitivity in thermal injury

Insulin resistance after burn is associated with alterations in postreceptor insulin signaling and abnormal glucose homeostasis. The renin-angiotensin system (RAS) exerts a largely inhibitory role on insulin action and is activated after burn injury. We hypothesized that upregulation of RAS is involved in the development of insulin resistance in burned rats. We examined the possibility that an angiotensin II type 1 (AT1) receptor blocker, losartan, enhances insulin sensitivity and thereby increases glucose tolerance in thermally injured rats. A 30% body surface area burn was induced by immersion of the dorsum into water with a temperature level of 95 degrees C for 15 s. Sham-burned rats were immersed in water with a temperature level of 23 degrees C. Losartan (30 mg/kg per day) or placebo (water) was given by gavage immediately after the burn injury and daily for 3 days postburn injury, resulting in sham-burned, burn placebo, and burn losartan groups. Plasma angiotensin II levels between burn placebo and sham-burned groups were not different 3 days after burn injury. However, losartan significantly increased plasma angiotensin II levels (P < 0.05), suggesting blockade of the AT1 receptor. An oral glucose tolerance test was performed 3 days postburn injury. There was an increase in the area under the curve for insulin and the glucose insulin index in burn placebo group as compared with sham-burned group, indicating insulin resistance. Losartan treatment abolished the insulin resistance in burn as evidenced by an area under the curve for insulin and glucose insulin index lower than that in the burn placebo group and similar to that in the sham-burned group. This suggests that insulin resistance and glucose intolerance associated with burn injury is, in part, caused by RAS.