Biomedical subjects
Publications and source records attributed to J S Palmer.
Congenital urologic abnormalities in males may contribute to sexual dysfunction seen in young men. It is the purpose of this paper to review some of the more common congenital urologic anomalies and their impact on sexual and reproductive function.
We studied sequelae of prenatal plus infantile exposure of male rabbits to vinclozolin, because it is ingested by women and children. Female Dutch-Belted rabbits (7-10/group) were treated daily per orum from gestation day 15 through post-natal week 4 to provide 0, 7.2, or 72 mg vinclozolin/kg dam's body weight/day. Vinclozolin had no effect on maintenance of pregnancy, growth of pups, age at testicular descent or weight of organs. Concentrations of serum LH or testosterone at 6, 12, or 24 weeks of age were unaffected. However, FSH was lower (P < 0.05) in both vinclozolin groups at all three ages. Following injection of GnRH at 12 or 24 weeks, the increase in FSH was less (P < 0.05) in both vinclozolin groups, as was testosterone at 12 weeks of age. After full sexual maturity, 2 of 7 low dose rabbits were uninterested in female or male teasers and never achieved erection or ejaculation. Overall, rates of ejaculation failure were: control 0% (0/48), low dose 29% (12/42), and high dose 5% (3/60). Daily sperm production per gram of testis and total number of sperm per ejaculate in both vinclozolin groups were similar (P > 0.1) to controls. However, semen from vinclozolin rabbits contained over two times more (P < 0.05) morphologically abnormal spermatozoa, mostly nuclear and acrosomal defects, than semen from controls. Seminiferous tubules with degenerative changes were more frequent (P < 0.05) in vinclozolin rabbits than in controls. Lesions included syncytia of spherical spermatids and desquamation of germ cells. Hence, developmental exposure to vinclozolin caused presumably permanent changes in copulatory ability, secretion of FSH, and spermiogenesis.
AIMS: This project aimed to investigate the mechanism of attachment of the vegetative cells and spores of thermophilic bacilli to stainless steel with a view to devising strategies to limit biofilm development and survival. METHODS AND RESULTS: Spores and vegetative cells of bacterial isolates were exposed to protein denaturing agents (sodium dodecyl sulphate (SDS) and trypsin) and polysaccharide removing agents (sodium metaperiodate, trichloroacetic acid (TCA) and lysozyme). Treatment with sodium metaperiodate, TCA and lysozyme increased the number of vegetative cells attaching in many of the strains studied, while SDS and trypsin decreased attachment. Spores attached to stainless steel in greater numbers than vegetative cells, and the various treatments had less effect on this attachment than for vegetative cells. Viability of the cells or spores was not an important factor in attachment, as cells and spores rendered non-viable also attached to stainless steel in similar numbers. Coating the stainless steel with skim milk proteins decreased the attachment of both vegetative cells and spores. There was no correlation between the degree of attachment and the amount of extracellular polysaccharide (EPS) produced by each strain, surface hydrophobicity or zeta potential of vegetative cells or spores, though spores were found to be more hydrophobic than vegetative cells. CONCLUSIONS: The results suggest that biofilm formation by these thermophilic bacilli is probably a multifactorial process, and that cell-surface proteins play a very important role in the initial process of attachment during the formation of biofilms by these bacteria. SIGNIFICANCE AND IMPACT OF THE STUDY: This information will provide direction for developing improved cleaning systems to control biofilms of thermophilic bacilli in dairy manufacturing plants.
We evaluated sequelae to early exposure of male rabbits to drinking water containing chemicals typical of ground water near hazardous waste sites. The mixture (p.p.m. at 1x) was 7.75 arsenic, 1.75 chromium, 9.25 lead, 12.5 benzene, 3.75 chloroform, 8.5 phenol and 9.5 trichloroethylene. Dutch-Belted does received mixture at 0x (deionized water; control), 1x or 3x as drinking water from day 20 pregnancy through weaning. Exposure of individual males (7-9/treatment) continued until 15 weeks (adolescence); then, all males received deionized water. At 57-61 weeks of age, ejaculatory capability and seminal, testicular, epididymal and endocrine characteristics were evaluated. At 10 opportunities with a female teaser, all seven control males ejaculated every time, but 12 of the 17 treated males failed to express interest, achieve erection and/or ejaculate on one to five occasions; four of the 12 accomplished ejaculation with a second male teaser. Total spermatozoa/ejaculate and daily sperm production were unaffected. However, treatment caused (P < 0.03) acrosomal dysgenesis and nuclear malformations. Baseline serum concentrations of LH were lower, but with borderline significance (P = 0.05). Testosterone secretion after exogenous human chorionic gonadotrophin (P < 0.04) was low. Thus, even at 45 weeks after last exposure to drinking water pollutants, mating desire/ability, sperm quality, and Leydig cell function were subnormal.
Several cystic fibrosis (CF) mouse models demonstrate an increased susceptibility to Pseudomonas aeruginosa lung infection, characterized by excessive inflammation and high rates of mortality. Here we developed a model of chronic P. aeruginosa lung disease in mice homozygous for the murine CF transmembrane conductance regulator G551D mutation that provides an excellent model for CF lung disease. After 3 days of infection with mucoid P. aeruginosa entrapped in agar beads, the G551D animals lost substantially more body weight than non-CF control animals and were less able to control the infection, harboring over 40-fold more bacteria in the lung. The airways of infected G551D animals contained altered concentrations of the inflammatory mediators tumor necrosis factor-alpha, KC/N51, and macrophage inflammatory protein-2 during the first 2 days of infection, suggesting that an ineffective inflammatory response is partly responsible for the clearance defect.
Risk of cutaneous malignant melanoma (CMM) is increased in sun-exposed whites, particularly those with a pale complexion. This study was designed to investigate the relationship of the melanocortin-1 receptor (MC1R) genotype to CMM risk, controlled for pigmentation phenotype. We report the occurrence of five common MC1R variants in an Australian population-based sample of 460 individuals with familial and sporadic CMM and 399 control individuals-and their relationship to such other risk factors as skin, hair, and eye color; freckling; and nevus count. There was a strong relationship between MC1R variants and hair color and skin type. Moreover, MC1R variants were found in 72% of the individuals with CMM, whereas only 56% of the control individuals carried at least one variant (P<.001), a finding independent of strength of family history of melanoma. Three active alleles (Arg151Cys, Arg160Trp, and Asp294His), previously associated with red hair, doubled CMM risk for each additional allele carried (odds ratio 2.0; 95% confidence interval 1. 6-2.6). No such independent association could be demonstrated with the Val60Leu and Asp84Glu variants. Among pale-skinned individuals alone, this association between CMM and MC1R variants was absent, but it persisted among those reporting a medium or olive/dark complexion. We conclude that the effect that MC1R variant alleles have on CMM is partly mediated via determination of pigmentation phenotype and that these alleles may also negate the protection normally afforded by darker skin coloring in some members of this white population.
PURPOSE: Now that individuals with spina bifida live well into adulthood erectile dysfunction has become a recognized associated medical disorder. To our knowledge no study has dealt specifically with treatment of erectile dysfunction in men with spina bifida. Therefore, we conducted a prospective, blinded, randomized, placebo controlled, dose escalation, crossover study to determine the ability to treat erectile dysfunction in men with spina bifida with sildenafil citrate. MATERIALS AND METHODS: Erectile dysfunction was diagnosed in 15 men 19 to 35 years old with spina bifida who were assigned to take 4 sets of tablets, 5 tablets per set, in a random order. All patients took 25 and 50 mg. sildenafil and 2 identical looking sets of corresponding placebos 1 hour before planned sexual activity. Efficacy was assessed by the effect of treatment compared to baseline, that is before treatment, on rating of erections (scored from 0 to 10), duration of erections, frequency of erections based on response to question 1 (scored from 0 to 5) of the International Index of Erectile Function and confidence to obtain an erection based on response to question 15 (scored from 1 to 5) of the International Index of Erectile Function. RESULTS: Improved erectile function was reported while on sildenafil by 12 (80%) men compared to baseline and placebos. There was a significant dose dependent improvement of erectile function with both 25 and 50 mg. sildenafil compared to baseline (p <0.05), as mean erectile score increased by 50% and 88%, mean duration of erections increased by 192% and 266%, mean frequency of erections increased by 61% and 96%, and mean level of confidence increased by 33% and 63%, respectively. Furthermore, 50 mg. sildenafil provided greater improvement in all 4 parameters compared to 25 mg. The placebo results were not significantly different compared to baseline for any of the parameters. CONCLUSIONS: Erectile dysfunction in patients with spina bifida is a medically treatable condition. Sildenafil is effective in this patient population and improves level of sexual confidence.
Natural multiple pregnancy in women leading to dizygotic (DZ) twins is familial and varies across racial groups, suggesting a genetic predisposition. Mothers of DZ twins have a higher incidence of spontaneous multiple ovulation and elevated FSH concentrations. FSH release is controlled by feedback of inhibin peptides from the ovary, and immunization against inhibin alpha-subunit results in an increased ovulation rate in animals. The inhibin alpha-subunit is therefore a candidate gene for mutations that may increase the frequency of DZ twinning. Restriction digests of a PCR product from exon 1 with the enzyme SpeI detects a C/T polymorphism at bp 128 with two alleles of 447 and 323/124 bp. The polymorphism was typed in 1,125 individuals from 326 pedigrees with 717 mothers of spontaneous DZ twins. The alpha-inhibin locus mapped within 3 centimorgans of D2S164, and linkage with DZ twinning was excluded [decimal log odds ratio (LOD) score, -2.81 at theta = 0]. There was complete exclusion of linkage (LOD, less than -2) of a gene conferring relative risk 1.8 (lambdas, >1.8) across the chromosome, except at the p-terminus region and a small peak (maximum LOD score, 0.6) in the region of D2S151-D2S326. Analysis using either recessive or dominant models excluded linkage with DZ twinning in this population (LOD score, less than -2.5) across chromosome 2. We conclude that dizygotic twinning is not linked to variation in the alpha-inhibin locus. The results also suggest that mutations in other candidates on chromosome 2, including the receptor for FSH and the betaB-inhibin subunit (INHBB) cannot be major contributors to risk for DZ twinning.
Explore the source record for details and available documents.
We undertook a prospective, blinded, randomised, placebo-controlled, dose escalation, crossover study that showed that erectile dysfunction in spina bifida is medically treatable, specifically with sildenafil citrate.
OBJECTIVES: Although extensive research has been conducted on the normal anatomy and physiology of the epididymis, the effects of ischemia on the organ have not been primarily investigated. The aim of the present study was to investigate the macroscopic and microscopic effects of prolonged ischemia on the epididymis and the factors that may contribute to its resistance to ischemia. METHODS: Six groups of male Sprague-Dawley rats (6 rats/group) were studied. Groups 1, 2, and 3 underwent a sham operation of 4, 8, and 12 hours, respectively, and groups 4, 5, and 6 underwent 4, 8, and 12 hours of ischemia, respectively. The ipsilateral testes and epididymides were monitored throughout the experiment. At the conclusion of the experiment, bilateral orchiectomy was performed, and structures were histologically evaluated. RESULTS: There were no abnormal macroscopic findings of the bilateral epididymides of groups 1, 2, and 3 or of the contralateral, control epididymides of groups 4, 5, and 6. Macroscopically, there was a direct correlation between the length of ischemia and the degree of hemorrhagic discoloration of the proximal caput. The degree of hemorrhagic infiltration noted microscopically was consistent with the macroscopic observations. The epithelia of the ischemic epididymides remained intact with numerous microvilli. CONCLUSIONS: The results of this study suggest that the epithelium of the epididymis is relatively resistant to ischemic damage compared with the gonad during testicular ischemia.
We report a case of complete, unilateral seminal vesicle duplication without concomitant reproductive duct or renal anomalies encountered during radical retropubic prostatectomy. We also discuss the possible embryologic origin of this anomaly and the clinical implications.
Explore the source record for details and available documents.
PURPOSE: The mechanism of testicular ischemia-reperfusion injury has not been well delineated. We determined the efficacy of a biocompatible surfactant (tetronic 1107) to reduce tissue injury and evaluated cell membrane integrity as reflected by calcium ion permeability in an in vivo animal model of testicular ischemia-reperfusion. MATERIALS AND METHODS: Three groups of male Sprague-Dawley rats (6 per group) were studied. Group 1 was the nonoperative control, and groups 2 and 3 underwent 4 hours of unilateral testicular ischemia followed by 4 hours of reperfusion. Ten minutes after reperfusion 0.4 ml. saline was administered intravenously to group 2 and 180 mg./kg. surfactant tetronic 1107 to group 3. 99mTechnetium pyrophosphate was used to monitor calcium ion uptake by the ipsilateral and contralateral testicles. Both testicles were also examined histologically. RESULTS: The surfactant treated animals had markedly diminished hemorrhagic discoloration and vascular congestion compared to saline treated animals. These results were confirmed microscopically with improved nuclear chromicity and disarray of germ cell layers of the seminiferous tubules. The surfactant treated group also had a statistically significant (p <0.05) reduction in radiotracer uptake compared to the saline treated animals, confirming a reduction in calcium ion permeability. CONCLUSIONS: The results of this study suggest that tetronic 1107 is effective in reducing tissue damage in a testicular ischemia-reperfusion animal model.
Community Health Planning (CHP) is one of the tools that states and localities use to develop health policies and programs. The author argues that, for CHP to succeed, it must include both positive/hierarchic data as well as interpretive information. To augment the discussion, the author discusses the State of Tennessee's effort to revamp its public health mission and strategies as specifically implemented in one county. The author contrasts the two types of data generated and argues that each has a legitimate claim in the CHP process: the "positive" data in the form of epidemiological statistics to inform the stakeholders and the "interpretive data" in the form of stakeholder participation for ownership of the process. The author then draws implications for states and localities to use diverse information sources as they improve services and service delivery to citizens and recipients.
Explore the source record for details and available documents.
The article presents an overview of the design and application of a real-time patient routing system, based on barcode and local area network technology, that was designed to track the progress of patients during the perioperative process. We present data on all patients undergoing ambulatory surgery. Patients' progress during their surgical stay was recorded at 17 strategic events using this real-time patient tracking technology. These times were used to identify inefficiencies in the perioperative process by identifying bottlenecks and areas of high variation. We found that both raw and actual operating room (OR) utilization efficiency was less than 50%. Points of high variation in a patient's progress occurred during the time from admit to the hospital until the patient was ready for the OR; the time from when a patient was ready for the OR until they were called for; and the time a patient spends in the OR preoperative holding room. Causes for variation were identified and traced back to individual procedures, activities, and work processes. Multidisciplinary improvement teams were created to improve the pinpointed problem areas. The real-time patient routing system is a process that has proven to be highly valuable to all participants in the surgical process in bringing about rational, data driven efficiencies in perioperative services. This process has the potential to facilitate multidisciplinary cooperation in efforts to contain and reduce costs of perioperative services.
PURPOSE: Our aim was to quantify objectively the degree of vascular insufficiency produced by twisting versus clamping the spermatic cord, and determine the contribution of the vasal vessels to these changes using the laser Doppler flowmeter. MATERIALS AND METHODS: Three groups of 12 male Sprague-Dawley rats each were studied. Group 1 underwent 720-degree torsion of the spermatic cord, group 2 underwent vascular clamping of the spermatic cord with 1 clamp, excluding the anatomically separate vasal vessels, and group 3 underwent vascular clamping of the entire spermatic cord and vasal vessels with 2 clamps. Blood flow and histological changes were determined. RESULTS: Vascular clamping of the spermatic cord in groups 2 and 3 resulted in a significant decrease in testicular blood flow compared to 720-degree torsion (p < 0.05). These flow changes correlated with more severe and reproducible gross changes, and histological features of seminiferous tubule degeneration compared to spermatic cord twisting. CONCLUSIONS: In the rat clamping the spermatic cord is a more severe and reproducible model of testicular torsion than 720-degree torsion. The contribution of the vasal vessels to the decrease in blood flow and resulting histological degeneration after testicular ischemia is negligible in the rat.