Use of plastic scrap in asphalt mixtures added by dry method as a partial substitute for bitumen.

In recent decades, the generation of plastic waste has increased substantially worldwide, with the result that more of such waste is introduced into the environment. Currently, most polymers (polyethylene terephthalate, polyethylene, polyvinyl chloride, and others) are recycled. However, some are rejected for recycling in the primary separation processes due to their physical condition, contamination, or size. These materials are called plastic scrap. In this research, the use of plastic scrap added by dry method was evaluated as a replacement for bitumen in asphalt mixtures. Two sizes of plastic scrap, coarse and fine, were considered. An AC16S semi-dense mixture was designed for this purpose, with a 10% reduction in binder, and 10% and 20% of plastic scrap binder was added in coarse and fine sizes. The results obtained in the Marshall stability and flow test showed reduced moisture damage, greater indirect tensile strength, higher air void content, and a 2% decrease in the conserved tensile strength ratio while the same usage field as the conventional mixture was maintained. Meanwhile, significant decreases in plastic deformations, as compared to traditional values, were obtained from resilient modulus and rutting tests.

Increased incidence of depressive symptoms in men with erectile dysfunction.

OBJECTIVES: To investigate the hypothesis that men with erectile dysfunction (ED) have a higher incidence of depressive symptoms compared with age-matched control subjects. We also hypothesized that depressive symptoms impact on the level of libido and on the success of treatment of ED. METHODS: One hundred twenty men with ED or benign prostatic hyperplasia (BPH) were divided into three groups. Group 1 had ED only, group 2 had BPH only, and group 3 had both ED and BPH. Patients were screened for depressive symptoms using the Primary Care Evaluation of Mental Disorders and the Beck Depression Inventory. They were also surveyed for comorbidity, marital status, severity of ED, level of libido, prior ED treatment choice (if any), success of treatment, and others. RESULTS: One hundred patients completed the questionnaires. Depressive symptoms were reported by 26 (54%) of 48 men with ED alone, 10 (56%) of 18 men with ED and BPH, and 7 (21 %) of 34 men with BPH alone. Patients with ED were 2.6 times more likely to report depressive symptoms than men with BPH alone (P < 0.005). Patients with depressive symptoms reported lower libido than other patients (P < 0.0001). Severity of comorbidities did not differ among the three groups. A total of 33 patients with ED had prior treatment for ED using penile injections or vacuum devices. All 15 (100%) patients with ED only continued treatment and were satisfied with its outcome, whereas only 7 (38.9%) of 18 patients with ED and depressive symptoms continued treatment (P < 0.00021). CONCLUSIONS: ED is associated with high incidence of depressive symptoms, regardless of age, marital status, or comorbidities. Patients with ED have a decreased libido compared with control subjects. In addition, patients with depressive symptoms have a lower libido than patients without depressive symptoms. Patients with ED and depressive symptoms are more likely to discontinue treatment for ED than other patients with ED. These data emphasize the importance of a multidisciplinary approach to the treatment of erectile dysfunction.

Use of magnetic resonance urography.

OBJECTIVES: Magnetic resonance urography (MRU) is a new technique that uses heavily weighted T2 coronal images with fat suppression pulse. Urine appears white on MRU, resembling an intravenous urogram (IVU). Contrast agents are not necessary. This study describes the use of MRU in the diagnosis and treatment of patients with hematuria. METHODS: One hundred six patients with microscopic or gross hematuria and 6 normal volunteers underwent MRU between 1992 and 1995. A modified, heavily weighted T2 technique with intravenous administration of furosemide and ureteral compression was used. Thirty-two patients had other imaging techniques as well for comparison. RESULTS: MRU provided high-resolution images in almost all cases; 73 (69%) had a normal MRU. Significant findings in the 33 patients with abnormalities included renal cysts in 17 (51%), renal cell carcinoma in 6 (18%), transitional cell carcinoma in 5 (15%), ureteropelvic junction obstruction in 3 (9%), and stones causing obstruction in 6 (18%). Five patients with renal failure also had good visualization of the entire urinary tract. MRU was comparable to other imaging modalities except in identifying nonobstructing calculi. CONCLUSIONS: MRU provides an alternative to conventional imaging of the urinary tract, especially in those patients who have contraindications to ionizing radiation and contrast agents. Improvements in resolution, technique, and cost have to be addressed before it can be used regularly in urologic practice.

Ureteral obstruction secondary to indinavir in the pediatric HIV population.

Indinavir sulfate is a protease inhibitor used in the treatment of the human immunodeficiency virus (HIV). This case report describes the radiographic and urologic manifestations of indinavir urolithiasis in two pediatric patients with acquired immunodeficiency syndrome (AIDS). Management involves aggressive hydration and surgical intervention when indicated.

Apoptosis in the rat penis after penile denervation.

PURPOSE: Despite the advances in nerve sparing prostatectomy for prostate cancer, some patients develop impotence or subjectively complain of a decrease in penile size. We hypothesized that these clinical observations may be explained by injury to the cavernous nerves resulting in programmed cell death (apoptosis) within the penis. We utilized a rat model of penile denervation in order to demonstrate apoptosis after denervation. METHODS AND MATERIALS: Fifteen male Sprague Dawley rats underwent abdominal exploration and bilateral cavernous neurotomy. Fifteen sham operations were performed as normal controls. The rats were sacrificed on postoperative day 1,2,3,6, and 10 and their penises were harvested. Messenger RNA was extracted and probed on a northern blot for sulfated glycoprotein-2 (SGP-2). SGP-2 is a gene product reported to be elevated in apoptotic tissues. Separate denervated and sham rats were used for DNA extraction (sacrificed postoperative day #2) in order to demonstrate the internucleosomal DNA fragmentation (laddering) found in apoptotic tissues. In addition, in situ histology was performed with ISEL techniques (in situ end labeling) to stain for apoptotic nuclei in denervated rats. RESULTS: Northern blot analysis showed a large increase in SGP-2 mRNA expression in the denervated rats with little detected in the sham operated group. DNA extraction studies revealed the presence of internucleosomal DNA fragmentation on agarose gel (a marker for apoptosis) in the denervated group versus intact high molecular weight DNA in the sham rats. In addition, in situ staining of denervated penile erectile tissue demonstrated apoptotic nuclei in the cavernous tissue. CONCLUSION: Apoptosis of penile erectile tissue occurs after denervation of the rat penis. This has not been previously described in the literature and may offer some explanation at the molecular level concerning the mechanism of impotence and/or decrease in penile size after radical prostatectomy.

The effects of prostatic manipulation on prostate-specific antigen levels.

Serum PSA determinations are an important part of the urologic evaluation for prostate cancer. DRE, TRUS, cystoscopy, and ejaculation have minimal effects on serum PSA levels. Prostatic massage, needle biopsy, TURP, and prostatitis can cause significant elevations of serum PSA (Table 1). These factors should be kept in mind for interpretation of PSA values.

Prostatic stents for benign prostatic hyperplasia.

Treatment options for benign prostatic hyperplasia (BPH) have developed rapidly over the past several years. These options include surgical intervention, medical therapy, and minimally invasive modalities such as prostatic stents. Prostatectomy remains the treatment of choice for symptoms that are the result of bladder outflow obstruction, with success rates of 85-90%. Medical therapy with selective alpha-1 antagonists, 5 alpha-reductase inhibitors, LHRH antagonists, antiandrogens, and aromatase inhibitors have increased in popularity and are mainly used to treat patients with mild to moderate prostatic obstruction. Prostatic urethral stents have recently emerged as an alternative treatment for BPH throughout Europe and Asia, but few investigators have used prostatic stents in the United States because of strict regulatory forces and a debate concerning the indications for these devices. The possibility of providing a treatment option for BPH to patients who are frail and elderly, as well as to patients with multiple medical problems, has prompted enthusiasm toward prostatic stents in the urologic community. The focus of this review will be an up-to-date discussion of the types of prostatic stent available, including a review of recent clinical trials involving the use of each available stent.

Penile gangrene associated with extensive Kaposi's sarcoma in patients with the acquired immunodeficiency syndrome.

Kaposi's sarcoma (KS) of the penis is a well-recognized manifestation of the acquired immunodeficency syndrome. Extensive KS of the genitalia progressed and caused penile gangrene in 2 cases. Management is palliative with urinary diversion via percutaneous suprapubic cystostomy.