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M I Resnick

Publications and source records attributed to M I Resnick.

At least 145 records · Page 8Linked to original sources
PubMed1991

The evaluation of urinary protein patterns in a stone-forming animal model using two-dimensional polyacrylamide gel electrophoresis.

The exact role of urinary proteins in kidney stone formation remains an area of controversy. Some investigators believe that urinary proteins are selectively incorporated within urinary calculi and as such have an active role in stone formation. Other investigators believe that urinary proteins are nonspecifically adsorbed into urinary crystals and thus have only a passive role in stone formation. In the current investigation a previously described stone-forming animal model (hyperoxaluric rat) was utilized along with an animal model for renal tubular injury (gentamicin nephrotoxicity) in an effort to clarify the role of urinary proteins in kidney stone formation. Urine specimens were collected before and after the induction of stone formation and after the induction of renal tubular injury. The purified proteins from each urine specimen were separated in two dimensions by electrophoresis resulting in a characteristic "map" of protein spots for each urine specimen. All animals in the stone-forming group had pathologic evidence of early stone formation (diffuse intranephronic calculosis). Early stone formation was consistently associated with a reduction in the excretion of low molecular weight urinary proteins (30,000 dalton and less than 20,000 dalton ranges). Alcian blue staining confirmed the presence of matrix within clumps of intranephronic calcium oxalate crystals. Renal tubular injury was associated with an increase in the excretion of low molecular weight proteins (approximate 20,000 dalton range) consistent with classical tubular proteinuria. These results suggest that low molecular weight urinary proteins are selectively incorporated within the crystalline structure of the stone early during its formation.

Animals↗
PubMed1991

External vacuum devices in the treatment of erectile dysfunction: a one-year study of sexual and psychosocial impact.

This prospective study assessed the sexual and psychosocial effects of 12 months' use of an external vacuum device in the treatment of erectile dysfunction. Results showed that the external vacuum device produced erections sufficient for intercourse in 87% of the men in our sample. The dropout rate was only 20% over the 12-month period. Use of the external vacuum device was associated with improvements in men's and their partners' sexual functioning. These improvements included erections of better quality, increased partner arousal, and increased frequency of orgasm and sexual satisfaction for men and women. The external vacuum device was also associated with decreases in general psychiatric symptomatology for men. Similar improvements in psychological functioning were not found for partners. Side effects and factors in patient and partner acceptance of the external vacuum device are discussed.

Adaptation, Psychological↗
PubMed1991

Sexual, psychological, and marital impact of self-injection of papaverine and phentolamine: a long-term prospective study.

This prospective study assessed the long-term effects of self-injection of papaverine hydrochloride and phentolamine mesylate along several critical domains for 42 men and 26 partners. Over the course of one year, men were, on average, injecting themselves five times monthly, with 84% of these injections producing satisfactory erections. Treatment resulted in statistically significant improvements in quality of erection, sexual satisfaction, frequency of intercourse, and coital orgasm. The women also demonstrated significant improvement in sexual satisfaction, arousal, frequency of intercourse, and coital orgasm. Decreases in general psychiatric symptomatology were apparent for men but not for partners. The dropout rate was 57%. The common side effects of treatment were development of fibrotic nodules (26%), abnormal liver function values (30%), and bruising (19%). We conclude that self-injection should be considered among the accepted treatments for erectile dysfunction. It does appear to enhance the sexual lives of men and women when the treatment is efficacious and the couple is motivated to utilize it.

Adaptation, Psychological↗
PubMed1991

Applications of prostate ultrasonography.

Transrectal ultrasonography of the prostate is a relatively new diagnostic modality being used with increasing frequency in the assessment of prostatic disease. Applications include tumour staging, assisted biopsy and assessment of prostate size. The role of this study for the early detection of carcinoma of the prostate remains controversial and its role in this regard remains to be determined.

Biopsy↗
PubMed1991

Diagnosis and management of vesicoenteric fistulas.

Vesicoenteric fistulas represent challenging clinical problems and may be characterized by difficulty in diagnosis as well as controversy in management. We present our experience with 56 patients with vesicoenteric fistulas. The results of our series were compared with a report of 1,100 in the literature during the past 20 years. Fecaluria (48 per cent), abdominal pain (43 per cent) and pneumaturia (41 per cent) were the most common presenting symptoms among the patients we studied. Fistulas were most frequently attributable to diverticulitis (52 per cent), Crohn's disease (18 per cent), carcinoma of the colon (11 per cent) or other pelvic malignant conditions (9 per cent). The most accurate diagnostic modalities in our series were cystoscopy (88 per cent), cystography (56 per cent) and barium enema (32 per cent). The combined findings of these studies led to the diagnosis of a fistula in all patients. Intravenous urography, intestinal endoscopy and computed tomography were less useful, providing a diagnosis in only 5, 6 and 11 per cent, respectively. Surgical treatment was single staged in 57 per cent and multistaged in 35 per cent, while 8 per cent of the patients underwent intestinal diversion only. Comparison of the single versus multistaged approaches revealed that the total complication rate, frequency of additional procedures, rate of infectious complications and length of hospitalization were no higher for the single stage group. Based on these findings, we advocate single stage repair, except in those patients who have unusual complications.

Barium Sulfate↗
PubMed1990

Enzymatic activities in extracts of small (20 +/- 5 mg) samples of prostatic carcinoma.

Previously, we reported that the activities of several enzymes extracted from prostatic cancers were closely related to the histologic grades (Gleason's grades) of the cancers. The survival of patients was more closely correlated with certain enzymatic activities than with Gleason's grades. Unfortunately, because our assays required relatively large amounts of tissue, the increasing proportion of patients who have needle biopsies as their only surgical procedure had to be excluded from our previous study. We now report a method that permits multiple enzyme assays to be carried out with much smaller amounts of tissue. This method will enable us to avoid the selection inherent in the exclusion of patients who have only needle biopsies and should permit the prospective study of most patients with prostatic carcinoma.

Arginase↗
PubMed1990

Applications of prostate ultrasonography.

Transrectal ultrasonography is a relatively new imaging modality that may be useful in the evaluation and management of patients with prostate cancer. Although cancer may have a characteristic appearance, it cannot always be reliably differentiated from benign conditions. While this technique has clinical applications in staging, monitoring tumor response to therapy, and assisting in biopsy, it is unclear as to whether useful information is obtained in the evaluation of patients with palpable disease. The role of transrectal ultrasonography in patients with nonpalpable disease or as a screening tool has yet to be determined. Other diagnostic tests in conjunction with ultrasound may in the future prove to be useful. Carefully performed prospective investigations with state-of-the-art equipment are still needed to further define the role of this diagnostic modality.

Biopsy↗
PubMed1990

Treating erectile dysfunction with external vacuum devices: impact upon sexual, psychological and marital functioning.

We evaluated prospectively the medical, sexual and psychosocial outcome of external vacuum devices in the treatment of erectile dysfunction. A total of 29 men regularly used such a device for 6 months and reported statistically significant improvements in erectile quality, frequency of intercourse attempts, frequency of orgasm and sexual satisfaction, as well as decreased psychiatric symptomatology, increased self-esteem and a trend toward improved marital satisfaction. Of the partners 18 reported improved sexual functioning, including increased frequency of orgasm, decreased masturbation and greater sexual satisfaction, with no changes in psychosocial parameters. The vacuum device was effective in producing erections in 89% of the men. Dropout, only 19% within 6 months, was primarily due to insufficient or pivoting erections and bruising. The most frequent adverse effects were blocked ejaculation and physical discomfort. Vacuum devices appear to provide a safe, effective, inexpensive, noninvasive treatment for erectile failure that enjoys high patient and partner acceptance.

Adult↗
PubMed1990

The characterization of soluble matrix proteins in selected human renal calculi using two-dimensional polyacrylamide gel electrophoresis.

In the current study a novel method of matrix extraction was utilized to permit the analysis of soluble matrix proteins of different types of kidney stones by two-dimensional electrophoresis. Two-dimensional polyacrylamide gel electrophoresis (SDS-PAGE) was performed on each soluble matrix protein sample resulting in a characteristic "map" of spots for each stone. The soluble matrix protein "map" was complex yet reproducible for each sample studied. The soluble matrix protein maps resembled urinary protein maps and stones of different crystalline content had significantly different matrix protein maps. The two-dimensional electrophoretic maps of matrix proteins extracted from calcium oxalate and uric acid calculi were similar to previously published two-dimensional electrophoretic maps of urinary proteins recovered from calcium oxalate and uric acid crystals. The majority of the protein maps were noteworthy for the presence of a low molecular weight pattern (MW less than 17,500 dalton) not seen in association with normal urinary protein maps. The significance of this pattern is not known but could be the result of degradation of larger proteins, evidence of renal tubular disease, or evidence of selective incorporation of low molecular weight proteins during stone formation.

Chromatography, Gel↗
PubMed1990

Urologic changes after cauda equina compression in dogs.

Relative degrees (25%, 50% or 75%) of constriction of the entire cauda equina at the seventh lumbar level were performed on eighteen pure bred female beagle hounds by surgically implanting a circular polyethylene loop with an imbedded stainless steel wire. The wire was mechanically constricted by external control and the degree of compression was confirmed by pre- and postoperative magnetic resonance imaging or computed tomography scanning. A control group of two dogs had laminectomy only. Neurologic function was evaluated daily. Cystometrics were performed on each dog after constriction had been present for three months. Cortical evoked potentials (CEPs) were obtained on all dogs preoperatively, immediately following constriction and at monthly intervals for three months. Dogs were sacrificed at three months and the cauda equina and spinal cord were examined histopathologically. Cystometric tracings were noted to become a flat line with 75% compression of the cord. Less compression had minimal effect on the cystometric curves. The mean latency, determined by cortical evoked potentials, was noted to increase by 3.2%, 7.8%, and 17.2% immediately after 25%, 50% and 75% constriction, respectively. Histologic changes ranged from occasional enlargement of the axons on the periphery of the cauda equina with 25% constriction to severe loss of all axons and atrophic roots at the level of the constricting band with 75% constriction.

Animals↗
PubMed1990

Application of office ultrasound in the management of the spinal cord injury patient.

The effectiveness of office ultrasonography of the bladder and kidneys to provide routine urological followup was assessed in the outpatient spinal cord injury clinic. A total of 86 asymptomatic spinal cord injury patients underwent office ultrasonography of the kidneys and bladder as part of the routine urological followup. There were 106 ultrasound scans performed. Of the patients 68 had a blinded excretory urogram for comparison, including 20 who underwent additional studies (computerized tomography scans of the abdomen and pelvis, and/or radiologist-performed ultrasound examinations of the kidneys and bladder). All 18 patients who underwent office ultrasound but not excretory urography each underwent computerized tomography scans of the abdomen and pelvis and/or radiologist-performed ultrasound examinations of the kidneys and bladder. Office ultrasound detected 5 of 6 kidney stones, 6 of 6 hydronephrotic kidneys, 5 of 7 renal masses (4 of 6 cysts and 1 of 1 renal tumor), 3 of 3 bladder stones and 3 of 3 bladder diverticula. Subtle changes of chronic renal infection noted on excretory urography in 4 patients were not detected on corresponding ultrasound scans but voiding cystourethrograms revealed no reflux, and comparison to prior studies confirmed that these renal units were stable. Outpatient ultrasonography performed by the urologist proved to be a cost-effective and sensitive screening examination for urological disorders in the spinal cord injury population. The technique is easily learned, well tolerated and indicated when further urological evaluation is required.

Cost-Benefit Analysis↗
PubMed1990

Secondary urolithiasis.

Urolithiasis may be associated with a wide range of unrelated conditions that in various ways predispose to the development of urinary tract calculi. The most common such conditions are urinary tract infection, structural abnormalities of the urinary tract, drugs, and foreign bodies. Evaluation of patients must rule out other underlying metabolic disorders. Treatment must address not only the calculi but also the correction or elimination of the predisposing factors.

Humans↗
PubMed1990

Detection of clinically occult prostate cancer.

A large number of cases of prostatic carcinoma are discovered unexpectedly by simple prostatectomy performed for presumed benign disease. The ability to discover these cancers preoperatively is an appealing concept, in other words, to screen: the use of a test to detect a disease in an asymptomatic individual. The ideal screening test would be noninvasive, inexpensive, reliable, and reproducible. It would also have a high sensitivity and specificity, neither allowing a disease process to be missed by a falsely negative result nor leading to unnecessary and more invasive studies by a falsely positive one. It has been suggested that an acceptable screening test have a sensitivity of at least 95 per cent and a specificity of 100 per cent. An equally important criterion for a successful screening program for cancer has to do with the biologic potential of the discovered malignancy. The adage is that more men die with prostate cancer than of prostate cancer. However, the biologic potential of prostate cancer has not been fully elucidated, and it is not entirely clear who will benefit from treatment and who should be left alone. At the present time, noninvasive imaging modalities and biochemical markers are not clinically useful in detecting occult prostatic carcinoma. Furthermore, no study has proved that routine screening reduces the mortality rate from prostate cancer. Many authors believe that screening men for prostate cancer should be regarded as investigational and that currently, only screening programs for breast and cervical cancer have been fully demonstrated to be effective. New studies are needed that include control groups who are not subjected to the early diagnostic modality, assessing both the disadvantages of the screening program and the potential benefits.

Acid Phosphatase↗
PubMed1990

Metabolic evaluation of urolithiasis.

The relatively simple scheme described here should become part of the urologist's stone evaluation plan. It allows for the rapid identification of the metabolic disorders and the prompt implementation of appropriate therapy. With a stone remission rate of 70 to 90 per cent and a reduction in the stone formation rate of 88 to 100 per cent, an overwhelming incentive exists to master this evaluation scheme.

Calcium↗
PubMed1989

5'-nucleotidase activity in prostatic carcinoma and benign prostatic hyperplasia.

In light of previous reports of alterations in 5'-nucleotidase activity in neoplastic conditions, 5'-nucleotidase activity was examined histochemically in tissue sections and quantified biochemically in extracts of human hyperplastic prostates and prostatic carcinomas obtained surgically. The 5'-nucleotidase activities per mg protein in extracts of 29 prostatic carcinomas were lower (P less than 0.0005) than in extracts from 10 samples of benign prostatic hyperplasia. The 5'-nucleotidase activity per mg protein in extracts of prostatic carcinoma from the 29 patients correlated (R = -0.369, P = 0.049) with the degree of histological differentiation; the extracts of poorly differentiated carcinomas contained low levels of 5'-nucleotidase. When age and histological differentiation (Gleason's grade) were adjusted, the enzyme activity per mg protein correlated (R = 0.242, P = 0.004) with patient survival. When all three parameters were considered together, i.e., histological grade of the tumor, 5'-nucleotidase extracted from the tumor, and age of the patient, they were found to be mutually complementary for the prediction of patient survival (R = 0.388, P = 0.0001). To our knowledge, this is the first report that prostatic epithelium expresses 5'-nucleotidase; further work will be required to define the reasons for the high levels of activity observed in prostates without cancer and for the decrease in the activity in prostatic carcinoma.

5'-Nucleotidase↗
PubMed1989

Staging renal carcinoma. What is sufficient?

We retrospectively reviewed the roentgenographic and pathologic staging of 64 patients with renal cell carcinoma to assess the role of the various staging modalities (ie, angiography, venacavography, bone scanning, ultrasound, computed tomography [CT], and magnetic resonance imaging). Specific attention was directed at detecting vena cava thrombus and metastatic bone disease, factors with a significant impact on the therapeutic approach. The findings support the role of CT as the principle tool for overall staging and the observation that venacavography is not indicated if CT has excluded caval thrombus. Similarly, routine bone scans are not warranted in the absence of an elevated alkaline phosphatase level or bone pain. The key to the more efficient utilization of imaging resources is understanding the capabilities of the technology available.

Adult↗