MR imaging of the male pelvis

Prostate and urinary bladder cancer are the most frequently encountered malignancies of the urinary tract. Appropriate use of the different imaging techniques is crucial for accurate assessment of prognosis and for the development of appropriate treatment planning. Especially determination of local tumor extension and detection of nodal or bone metastases is extremely important. In this regard MR imaging is the most promising imaging technique. Therefore, in this review its role in staging these malignancies is evaluated and compared with clinical staging, and other imaging techniques. Finally, future developments, such as new sequences, new contrast agents, the role of surface coils and MR-guided biopsy, are considered. Also, the preferred radiological approach is discussed.     

Body growth in early diagnosed vesicoureteric reflux

Body growth was studied in 32 subjects with vesicoureteric reflux (VUR), diagnosed following the prenatal finding of urinary tract dilatation, who had normal renal filtration function and who received antibacterial prophylaxis by the first few days of life. They were followed for 1–5 years (mean 2.3 years). Most had persistent VUR during the 1st year of life. Body growth performance was compared with that of 94 subjects with VUR diagnosed and treated by us after the neonatal period. During the follow-up period, none of the patients with prenatally detected VUR had a height Z score below –2, nor a weight-for-height index below 90%, and 1 had variations in height Z score ≥1. The difference in the percentage of patients with prenatally detected VUR (1/32) and those with VUR diagnosed and treated after the neonatal period (20/94) who had variations in height Z score ≥1 was significant (P=0.035). Patients with prenatally detected VUR and normal renal filtration function, given antibacterial prophylaxis by the first few days of life, have normal body growth, although VUR still persists. Received: 19 March 1998 / Revised: 10 February 1999 / Accepted: 10 February 1999     

Crystallization in the nephron

Recent experimental studies on the crystallization of calcium salts at different nephron levels support the theory that the initial formation of calcium concrements starts with an intratubular crystallization of calcium phosphate (CaP) and calcium oxalate (CaOx). CaP seems to be the initial crystallization product in pure CaP and mixed calcium phosphate–calcium oxalate (CaPCaOx) concrements, with the formation of CaP crystals at a nephron level above the collecting duct. Urinary macromolecules and cellular degradation products most probably promote this process. During the passage through the collecting duct, CaP might partly or completely dissolve at the lower pH encountered there. This might result in an increased concentration of calcium and hence an increased supersaturation with CaOx, which in turn can bring about a heterogeneous nucleation of CaOx on or around preformed CaP crystals or crystal aggregates. The final result will be mixed CaOxCaP or pure CaOx concrements. Pure CaOx concrements might also be the result of an initial CaOx crystallization at nephron levels above or in the collecting duct under conditions with a high urinary excretion of oxalate. Whether intratubular crystallization of calcium salts results in the formation of small harmless crystals excreted with urine or calcium stones appears to be determined by a complex process, involving kinetic factors that influence crystal growth and crystal aggregation and crystal retention. Received: 24 December 1998 / Accepted: 11 March 1999     

Anatomy and physiology of the male urethral sphincter and its preservation in prostatic surgery

Radical prostatectomy is commonly used in the management of localized prostate cancer. Urinary incontinence after prostatectomy is of great concern to many patients. Improved understanding of the anatomy of the external urethral sphincter complex has resulted in a statistically significant decrease in the incidence of postprostatectomy incontinence. Most recent anatomic studies have described the external urethral sphincter complex as consisting of an intrinsic rhabdosphincter surrounding the smooth musculature of the urethra and an extrinsic sphincter incorporating the levator ani muscle and the pelvic floor. Both form a condensed striated muscle ring around the membranous urethra. Preservation of as much as possible of the normal anatomy of the sphincter mechanism and its nerve supply results in an excellent return to continence after radical prostatectomy. Received: 26 February 1999 / Accepted: 20 May 1999     

Sprouting of bladder nerves into cystoplastic cecal segment in the rat

Incorporation of bowel into the bladder (enterocystoplasty) has been widely used to increase bladder capacity. It has been reported by others that the response of smooth muscle from the cystoplastic segment of the intestine shifts from that of the intestine (relaxation to α-agonists and ATP) to that of the bladder (contraction to α-agonists and ATP). This suggests a functional integration of the intestinal muscle into the bladder; the mechanisms are unknown. The aims of the present study were (1) to elucidate if there are signs of bladder nerves sprouting across the anastomosis into the intestinal segment, and (2) to study what happens with the intrinsic innervation of the intestinal segment. As a model, we used cecocystoplasty in rats. The bladder was opened and a patch of cecum with intact vascular supply was anastomosed to the bladder. After two to 11 months the rats were sacrificed and the bladders mounted as wholemounts and stained for acetylcholinesterase-containing nerves, or embedded in paraffin for histology. A pronounced degeneration of the myenteric plexus was found in the cecal segments. In some areas, this had proceeded to the extent that the ganglia were isolated ovoid lumps of cells with no apparent connection to other ganglia. Areas lacking ganglia and nerve trunks but still with muscle could be found in all specimens. Abundant axon bundles were demonstrated sprouting from the cut bladder nerves close to the anastomosis. The bundles spread out in a fan-like pattern or were organized as fewer thicker nerves. There were many nerve bundles entering the cecal segment where they branched and the diameter decreased till they no longer became visible. Some nerves reached surviving lumps of myenteric ganglion cells. The results show that the bladder nerves sprout into the anastomosed cecal segment. It is reasonable to assume that these nerves are responsible for the changes in receptor pharmacological properties of the cecal smooth muscle towards that of bladder muscle. Received: 30 October 1998 / Accepted: 18 May 1999     

Urinary lead as a possible surrogate of blood lead among workers occupationally exposed to lead

Objectives: The aim of the present study is to investigate whether lead (Pb) in urine (Pb-U) can be a valid surrogate of lead in blood (Pb-B), the traditional biomarker of exposure to lead in occupational health. Methods: Blood and spot urine samples were collected from 258 workers of both sexes occupationally exposed to lead. The samples were analyzed for lead by graphite furnace atomic absorption spectrometry, and the correlation between Pb-B and Pb-U was examined by linear regression analysis before and after logarithmic conversion. Results: The correlation coefficient (0.824; P < 0.01) was largest when the relationship between Pb-B and Pb-U was examined with 214 cases of one sex (i.e., men) after Pb-U was corrected for a specific gravity (1.016) of urine (Pb-Usg) and both Pb-B and Pb-Usg were converted to logarithms. The geometric means (GMs) of Pb-B and Pb-Usg for the 214 men were 489 μg/l and 81 μg/l, respectively. When Pb-Usg was assumed to be 100 μg/l in this set of correlations, the 95% confidence range of Pb-B for the group mean was narrow, i.e., 543–575 μg/l (with GM of 559 μg/l), whereas that for individual Pb-B values was as wide as 355–881 μg/l. Conclusions: The correlation of Pb-U with Pb-B among workers occupationally exposed to Pb was close enough to suggest that Pb-U may be a good alternative to Pb-B on a group basis, but not close enough to allow Pb-U to predict Pb-B on an individual basis. Received: 6 April 1999 / Accepted: 17 July 1999     

对苯二甲酸接触工人尿酶及微球蛋白的变化

选择１２７名ＴＰＡ作业工人进行动式个体采样,并留取１２７名ＴＰＡ作业工人当日工前工后尿样和７０名对照工人的工前尿。对尿样中γ谷氨酰转肽酶（ＧＧＴ）、碱性磷酸酶（ＡＬＰ）、乳酸脱氢酶（ＬＤＨ）、Ｎ乙酰βＤ氨基葡糖苷酶（ＮＡＧ）活性以及尿ＴＰＡ、α１微球蛋白（α１ＭＧ）、β２微球蛋白（β２ＭＧ）水平进行分析。结果显示,ＴＰＡ接触组尿ＧＧＴ、ＡＬＰ、ＬＤＨ、ＮＡＧ活性以及尿α１ＭＧ、β２ＭＧ水平与对照组相比无显著差别,而５～ｍｍｏｌ／ｍｏｌ．Ｃｒ尿ＴＰＡ负荷组工人尿β２ＭＧ与对照组相比有明显升高（Ｐ＜００５）,尿β２ＭＧ与尿ＴＰＡ负荷量呈现一定的剂量依赖关系。尿ＴＰＡ水平对尿酶活性、α１ＭＧ均未产生明显影响。不同累积接尘量和不同工龄的工人尿酶和微球蛋白无明显差异。提示ＴＰＡ对肾实质可造成一过性可逆性影响,尚不能说明肾实质受到器质性损伤。     

Iodine deficiency disorders in Bangladesh

An extensive iodine deficiency disorders survery was conducted in Bangladesh in 1993 to assess the latest iodine nutriture status of the country. The clinical variables of the survey were goitre and cretinism, and the biochemical variable was urinary iodine. The “EPI-30 cluster” sampling methodology was followed for selecting the survey sites. In each survey site, the study population consisted of boys and girls, aged 5–11 years, and men and women, aged 15–44 years, in about equal populations. the total number of survey sites was 78 and the total number of respondents was 30 072. The total number of urine samples was 4512 (15% sub-sample). The current total goitre rate (grade 1+grade 2) in Bangladesh is 47.1% (hilly, 44.4%; flood-prone, 50.7%; and plains, 45.6%). The prevalence of cretinism in the country is 0.5% (hilly, 0.8%; flood-prone, 0.5%; and plains, 0.3%). Nearly 69% of Bangladeshi population have biochemical iodine deficiency (urinary iodine excretion [UIE]<10 mg/dl) (hilly, 84.4; flood-prone, 67.1%; and plains 60.4%). Women and children are more affected than men, in terms of both goitre prevalence and UIE. The widespread severe iodine deficiency in all ecological zones indicates that the country as a whole is an iodine-deficient region. Important recommendations of global interest are made from the experience of the survey. An erratum to this article is available at .     

Contractile and cytoskeletal proteins in urinary bladder smooth muscle from rats treated with epidermal growth factor

Systemic treatment with epidermal growth factor (EGF) induces growth of all wall layers in the urinary tract of pigs and rats. The present study was initiated to describe morphological and biochemical changes in the bladder smooth muscle from rats treated with EGF for 4 weeks. Eight-week-old female Wistar rats were treated with subcutaneous injections of vehicle (n=16) or EGF (n=8, 150 g/kg per day) for 4 weeks. After EGF treatment the bladders were increased in weight [74.4±0.4 vs 122.1±0.5 mg, P<0.001 (mean ± SEM)]. Sodium dedecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) analyses of six bladders from each group revealed that the total amounts of actin, myosin and desmin were statistically significantly increased by 62%, 61% and 154%, respectively. The relative amounts of actin and myosin were unchanged whereas the desmin to actin ratio was significantly increased — as previously described in rat bladder smooth muscle hypertrophy. Light and electron microscopy of two bladders from each group revealed increased wall thickness involving all wall layers. The smooth muscle fibres at a midventral bladder location seemed only slightly hypertrophic — some degree of hyperplasia was therefore suspected. In conclusion, EGF treatment for 4 weeks induced a net synthesis of contractile and cytoskeletal proteins in the urinary bladder smooth muscle.     

Effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin on the in vivo and in vitro dechlorination of pentachlorophenol

The metabolism of pentachlorophenol has been studied in the rat after pretreatments with phenobarbital, 3-methyl-cholanthrene or 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). In addition to the previously identified metabolite, tetrachloro-p-hydroquinone, trichloro-p-hydroquinone has been identified in urine as a metabolite. The formation of the latter represents a type of dechlorination different from that of the formation of tetrachlorohydroquinone. The inducing agents, 3-methylcholanthrene and TCDD have similar effects on the dechlorination and increase the formation of tetrachloro-p-hydroquinone more pronounced than does phenobarbital. In contrast to phenobarbital they also increase the formation of trichloro-p-hydroquinone and the total elimination of pentachlorophenol and its metabolites. The in vivo findings are supported by in vitro studies with microsomes from rats pretreated with phenobarbital or TCDD. Use of the inhibitor -diethylaminoethyl-diphenyl propylacetate (SKF 525-A) in vitro showed a more pronounced inhibition on microsomes from phenobarbital-treated rats than on microsomes from untreated or TCDD-treated rats.Gas chromatography-mass spectrometry have been used for the identification and quantification of pentachlorophenol and its metabolites.

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Zusammenfassung Der Metabolismus von Pentachlorphenol nach Vorbehandlung der Versuchstiere (Ratten) mit phenobarbital, 3-Methylcholantren oder 2,3,7,8-Tetrachlordibenzo-p-Dioxin (TCDD) ist untersucht worden. Zu dem schon früher nachgewiesenen Metaboliten Tetrachlor-p-Hydrochinon wurde nun auch Trichlor-p-Hydrochinon als Harnmetabolit festgestellt. Die Bildung des letzteren stellt eine andere Art von Dechlorierung dar als diejenige die bei der Entstehung von Tetrachlor-p-Hydrochinon vorliegt. 3-Methylcholantren und TCDD haben ähnlichen Einfluß auf die Dechlorierung und steigern die Bildung von Tetrachlor-p-Hydrochinon mehr ausgeprägt als es bei phenobarbital der Fall ist. Im Gegensatz zu phenobarbital steigern sie auch die Bildung von Tri-chlor-p-Hydrochinon sowie die totale Eliminierung von Pentachlorphenol und von Metaboliten. Die in vivo-Befunde werden von in vitro-Studien mit Mikrosomen von mit phenobarbital oder TCDD vorbehandelten Ratten gestützt. Anwendung des Inhibitors -Diethylaminoethyl-Diphenyl-Propylacetat (SKF 525-A) zeigte in vitro eine ausgeprägtere Inhibition der Mikrosomen von mit phenobarbital behandelten Ratten als der Mikrosomen von unbehandelten oder TCDD-behandelten Ratten. Nachweis und Bestimmung von Pentachlorphenol und seinen Metaboliten wurden gaschromatographisch-massenspektrometrisch durchgeführt.