Injectable semi rigid penile prosthesis: study in rabbits and future perspectives

BackgroundPenile prostheses are the third option in the treatment of erectile dysfunction, however, despite their proven effectiveness, the occurrence of infections, advanced age of patients and comorbidities are the main limiting factors for this treatment modality. In the continuous search for biointegrated, clinically durable and minimally invasive treatment options, a possible model of penile prosthesis was sought through the use of intracavernous bacterial cellulose (BC) gel, in an experimental model of orchiectomized rabbits.MethodsThirty adult New Zealand rabbits were equally distributed into three groups: BC; vehicle and control. Each group was then subdivided according to the follow-up time of 3 and 6 months. Bilateral orchiectomy was performed 3 weeks before injection in the BC and vehicle groups. Pachymetry measurements of the penile axis, diameter and length were performed in situ. Histomorphometry analyzes of the corpora cavernosa (CC), thickness of the tunica albuginea, cell density, collagen and elastic fibers post-injection were also performed, in addition to immunohistochemistry for newly formed vessels.ResultsThe implant of BC increased both the length and thickness of the penis three and six months after the last injection, with a consequent increase in the diameter of the CC. On the other hand, the filling effect was not observed in the control and vehicle groups, confirming the degradation of this tissue after orchiectomy and the effectiveness of BC as a filling agent. Histomorphometry analyzes corroborate the mass effect of BC integrated into the tissue, permeated by predominantly lymphomononuclear inflammatory infiltrate, multinucleated giant foreign body cells, fibroblasts, elastic fibers and newly formed vessels, without degradation or loss of volume, even after six months of implantation.ConclusionsBiocompatibility and biointegration to the host tissue make BC a prosperous penile filling material, with local application and minimally invasive.     

Discovery and Validation of a Urinary Exosome mRNA Signature for the Diagnosis of Human Kidney Transplant Rejection

BackgroundDeveloping a noninvasive clinical test to accurately diagnose kidney allograft rejection is critical to improve allograft outcomes. Urinary exosomes, tiny vesicles released into the urine that carry parent cells’ proteins and nucleic acids, reflect the biologic function of the parent cells within the kidney, including immune cells. Their stability in urine makes them a potentially powerful tool for liquid biopsy and a noninvasive diagnostic biomarker for kidney-transplant rejection.MethodsUsing 192 of 220 urine samples with matched biopsy samples from 175 patients who underwent a clinically indicated kidney-transplant biopsy, we isolated urinary exosomal mRNAs and developed rejection signatures on the basis of differential gene expression. We used crossvalidation to assess the performance of the signatures on multiple data subsets.ResultsAn exosomal mRNA signature discriminated between biopsy samples from patients with all-cause rejection and those with no rejection, yielding an area under the curve (AUC) of 0.93 (95% CI, 0.87 to 0.98), which is significantly better than the current standard of care (increase in eGFR AUC of 0.57; 95% CI, 0.49 to 0.65). The exosome-based signature’s negative predictive value was 93.3% and its positive predictive value was 86.2%. Using the same approach, we identified an additional gene signature that discriminated patients with T cell–mediated rejection from those with antibody-mediated rejection (with an AUC of 0.87; 95% CI, 0.76 to 0.97). This signature’s negative predictive value was 90.6% and its positive predictive value was 77.8%.ConclusionsOur findings show that mRNA signatures derived from urinary exosomes represent a powerful and noninvasive tool to screen for kidney allograft rejection. This finding has the potential to assist clinicians in therapeutic decision making.     

Doppler Velocimetry Parameters of Periurethral Vessels in Postmenopausal Incontinent Women Receiving Estrogen Replacement

Estrogen deficit causes significant alterations in the lower urinary tract of women, largely affecting urinary continence mechanisms. The urethral vascular bed accounts for about one-third of urethral pressure, and as it undergoes marked hormonal influence we became interested in investigating its behaviour both prior to and during estrogen replacement. We selected 25 postmenopausal patients with urinary stress incontinence and studied the periurethral vessels by means of Doppler velocimetry, analyzing the number of vessels, systolic peak, minimum diastole, resistance and pulsatility indexes and the A/B ratio, prior to estrogen replacement and after 1 and 3 months of hormone use. We concluded that estrogen replacement alone in postmenopausal women with urinary stress incontinence increased the number of periurethral vessels, systolic peak and minimum diastole; however, a trend of no statistical significance towards the reduction of resistance and pulsatility rates of periurethral vessels was found; nor was a significant difference in the A/B ratio shown.     

Organ Donation: Cross-Sectional Survey of Knowledge and Personal Views of Brazilian Medical Students and Physicians

Objective

To assess the knowledge, attitudes, and behavior associated with cadaver organ donation and transplantation among medical students and physicians.

Patients and Methods

We randomly selected 350 medical students, 150 physicians, and 150 intensive care unit physicians. Each completed a questionnaire consisting of 9 self-administered items, from which we gathered data about their knowledge about brain death and criteria for the diagnosis of brain death; their hypothetical behaviors, assuming willingness to donate their own or their family's organs; their trust in physicians; and their confidence in a diagnosis of brain death made by physicians.

Results

We observed that knowledge about brain death increased with medical education level; the best results were noted in intensive care unit physicians. Agreement to transplant organs from brain-dead donors (odds ratio [OR], 4.58), confidence in brain-death diagnosis by physicians (OR, 2.17), and knowledge about criteria for the diagnosis of brain death (OR, 2.26) were predictors of willingness to donate one's own organs.

Conclusion

Enhanced medical knowledge of and involvement in donation are needed to achieve cadaver organ donation.     

Mortality Risk Factors and Validation of Severity Scoring Systems in Critically Ill Patients with Acute Renal Failure

Background. Risk stratification and prediction of outcome in acute renal failure patients in the intensive care unit are important determinants for improvement of patient care and design of clinical trials. Methods. In order to identify mortality risks factors and validate general and specific predictive models for acute renal failure (ARF) patients in the intensive care unit (ICU), 324 patients were prospectively evaluated. Multivariate analysis by logistic regression was utilized for identification of mortality risk factors. Discrimination and calibration were used to evaluate the performance of the following models at referral to nephrologist and at initiation of renal replacement therapy: APACHE II, SAPS II, LODS, and ATN-ISI. Organ failure was assessed by SOFA and OSF. Results. The hospital mortality rate was 85%. The identified mortality risk factors were: age ≥ 65 yr, BUN ≥ 70 mg/dL, ARF of septic origin, and previous hypertension. Serum creatinine ≥ 3.5 mg/dL, systolic blood pressure ≥ 100 mm Hg, and normal consciousness were associated with mortality risk reduction. Performance of all prognostic models was disappointing with unsatisfactory calibration and underestimation of mortality on the day of referral to the nephrologist and at initiation of renal replacement therapy. Conclusions. Cross-validation of prognostic models for ARF resulted in poor performance of all studied scores. Therefore, a specific model is still warranted for the design of clinical trials, comparison of studies, and for prediction of outcome in ARF patients, especially in the ICU.     

Reconstruction of parietal bone defects with adiposederived mesenchymal stem cells. Experimental study

Purpose:This study assessed the regeneration potential of mesenchymal stem cells (MSC) from adipose tissue associated with platelet-rich plasma (PRP) in bone regeneration.Methods:Thirty Wistar rats (Rattus norvegicus albinos) were divided into five groups (according to the grafting material and time to euthanasia): (1) autograft - 14 days (control), (2) autograft - 28 days (control), (3) MSC + PRP - 14 days, (4) MSC + PRP + papaverine - 14 days and (5) MSC + PRP + papaverine - 28 days. After euthanasia, the graft was removed and histological slides were prepared. They were assessed by a blinded pathologist using a previously published histological scale as parameter.Results:There was some degree of neoformed bone trabeculae (NBT) in 93.3% of the samples, as well as osteoblastic activity (OA). The autograft groups (14 and 28 days) had higher levels in the formation of bone trabeculae. Nonparametric data were analyzed using the Wilcoxon-Mann-Whitney test and proved not to be statistically significant at p < 0.05.Conclusions:Experimental parietal bone reconstruction, combining MSC, PRP and papaverine presented regeneration in all groups with no significant difference among them.Key words: Bone Regeneration, Platelet-Rich Plasma, Tissue Engineering, Rats     

The use of ablative lasers in the treatment of facial melasma

Melasma represents a pigmentary disorder that is difficult to treat. This study aimsto broadly review the use of ablative lasers (Er:YAG and CO2) in the treatment ofmelasma, presenting the level of evidence of studies published to date. A total of 75patients were enrolled in four case series studies (n=39), one controlled clinicaltrial (n=6) and one randomized controlled clinical trial (n=30). Studies on theEr:YAG laser showed better results with the use of short square-shaped pulses, whichdetermined low rates of post-inflammatory hyperpigmentation and long-lastingmaintenance of results. Likewise, studies on the CO2 laser proved the benefits ofshort pulse duration along with low-density energy. Post-treatment maintenance withthe use of antipigmenting creams was necessary and effective to sustain long-termresults. Ablative lasers may represent another useful and effective tool againstmelasma. Postinflammatory hyperpigmentation and difficulty in sustaining long-termresults still represent the main limitations to a broader use of ablative lasers.Based on actual evidence, the use of this technology should be restricted to patientswith recalcitrant disease. Further studies will help establish optimal laserparameters and treatment regimens.     

Case for diagnosis

The chondroid syringoma is a rare benign tumor, also called mixed cutaneous tumor by the presence of epithelial and mesenchymal components, consisting of sweat elements in cartilaginous, collagenous, myxoid or osseous stroma, among others. It mainly affects middle-aged men and is characterized by asymptomatic and slowgrowing, dermal or subcutaneous nodules. The most common locations are the head and neck. It is rare on the extremities. There are reports of malignant variants predominantly in women, located on the extremities. We report a case of a female patient with a lesion on the toe, with excellent outcome after surgical treatment.     

维A类化合物4-APR抑制肿瘤侵袭、转移的作用

用体内外实验模型,研究了新维A类化合物4-乙酰胺苯基维A酸酯(4-APR)对肿瘤侵袭、转移的抑制作用。4-APR 43.3mg·kg^-1po即能减少小鼠Lewis肺癌的自发性肺转移瘤数。半体内实验证明4-APR10^-5mol·L^-1和10^-6mol·L^-1对B16-F10癌细胞的人工肺转移瘤数分别抑制67.9%和36.6%。体外实验显示,4-APR对B16-F10细胞侵袭重组基底膜的抑制率分别为54.2%和41.9%。