bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Tamm‐Horsfall protein with normal and reduced sialic acid content upon the crystallization of calcium phosphate and calcium oxalate in human urine
Authors: HALLSON P.C. , CHOONG S.K.S. , KASIDAS G.P. , SAMUELL C.T.
Published: November 2003

Objective

 To examine the effects of Tamm‐Horsfall protein (THP) of normal and low sialic acid content on urinary crystallization, and establish whether there are changes conducive to the formation of kidney stones.

Materials and methods

 Purified samples of THP were recovered from the urine of non‐stone forming individuals. A portion of each THP sample was treated with the enzyme neuraminidase to yield the low sialic acid form of the protein. The two forms of THP were added separately to ultrafiltered urine and crystallization was then induced in the urine by evaporation at 37°C. Two types of experiment were then conducted with the crystals that formed; the rate at which the resulting calcium phosphate or calcium oxalate crystals sedimented in the evaporated urine was determined and the proportion of these crystals and protein which was retained when the urine was passed through a 75 &mgr;m sieve was measured.

Results

 Calcium phosphate and calcium oxalate crystals remained in stable colloidal suspension in ultrafiltered urine when in the presence of normal THP; these suspensions passed freely through the 75 &mgr;m sieves. When crystals formed in the presence of low sialic acid THP, the sedimentation was rapid and the crystals were readily retained with protein on the sieves.

Conclusions

 These results indicate that whilst normal THP inhibits urinary crystal aggregation, the properties of the low sialic acid form are consistent with the promotion of crystal aggregation and hence stone formation.
Topographical anatomy of the penile arteries
Authors: MARTÍNEZ‐PIÑEIRO L. , JULVE E. , MARTÍNEZ‐PIÑEIRO J.A.
Published: November 2003

Objective

 To determine the relationship of the penile arteries to anatomical landmarks and thus ease their identification, so avoiding injury during surgery.

Materials and methods

 The penile arteries in 12 formalin‐preserved adult male cadavers were dissected and the distances measured between the cavernosal arteries and both the endopelvic fascia and distal attachment of the crura to the ischial bones. The distance between the origins of both bulbar and cavernosal arteries, their length and the length of the cavernosal bodies and crural attachments were also measured.

Results

 Several anatomical variations, e.g. accessory pudendal arteries, multiple cavernosal and bulbar arteries, irrigation of cavernosal bodies by contralateral branches, anastomosis of cavernosal arteries with accessory pudendal branches, dorsal artery or bulbar artery as main branches of accessory pudendal arteries, were observed in 13 of the 24 specimens. The mean distances between the anterior attachment of the crura to the ischial rami and the site on the tunica albuginea where the cavernosal arteries penetrated the cavernosal bodies were 1.26 cm on the right and 0.69 cm on the left. The corresponding measurements between the cavernosal arteries and the endopelvic fascia were 5.68 cm (right) and 4.85 cm (left). The mean extracavernosal lengths of the right and left cavernosal arteries were 2.47 and 2.2 cm, respectively.

Conclusions

 Multiple anatomical variations of the arterial penile anatomy occur frequently. Surgery at the penile hilum may easily damage the cavernosal arteries, which lie medially to the dorsal nerves and arteries of the penis, have an extracavernosal length of about 2.3 cm and perforate the tunica albuginea about 1 cm distally to the anterior attachment of the crura to the ischial ramus.
Interstitial laser coagulation in the treatment of benign prostatic hyperplasia using a diode‐laser system with temperature feedback
Authors: De La ROSETTE J.J.M.C.H. , MUSCHTER R. , LOPEZ M.A. , GILLATT D.
Published: November 2003

Objective

 To report the initial results of the treatment of patients with benign prostatic hyperplasia using interstitial laser coagulation (ILC) performed with a temperature‐sensing laser system.

Patients and methods

 Twenty‐five patients were treated using ILC and in 12, 78 temperature‐power curves were recorded. The aim of the treatment was to maintain a temperature of 100°C during the entire treatment cycle, using the temperature‐triggered feedback system. The time to reach the maximum temperature, the maximum temperature and the energy delivered were related to the location of the punctures within the prostate. The clinical outcome at 1 and 3 months was evaluated with symptom scores and uroflowmetry variables.

Results

 Heating at the apex seemed to require less energy to achieve and maintain higher temperatures than heating of the median lobe or base of the prostate. Patients improved markedly 1 and 3 months after treatment; the respective mean symptom scores improved from 20.6 before treatment to 9.4 and 6.9, the maximum urinary flow rates from 9.1 mL/s to 14.1 mL/s and 20.3 mL/s and the post‐void residual volume decreased significantly from 71 mL to 31 mL and 11 mL. No significant complications (incontinence, impotence or haemorrhage requiring transfusion) occurred.

Conclusion

 The energy needed to achieve coagulation differed at sites within the prostate, depending on local circumstances. Good results were obtained using the tissue‐adaptive laser system.
Early genetic and cellular responses in the smooth
Authors: CHUANG Y.H. , CHUANG W.L. , LIU K.M. , CHEN S.S. , HUANG C.H.
Published: November 2003

Objective

 To investigate the early genetic and cellular responses in the smooth muscle layer of completely obstructed ureters, and to determine whether myocytes proliferate (hyperplasia) in the ureters during the early stage of obstructive uropathy.

Materials and methods

 The study comprised 35 female Sprague‐Dawley rats which had undergone unilateral ligation of their ureters. After ureteric ligation, five rats each were killed and examined at 0.5, 1, 2, 4, 8, 16 and 24 h after ligation. The proximal portion of the ureters was prepared for light and electron microscopy. The expression of c‐Fos, c‐Jun, c‐Myc and Ki‐67 antigen was assessed immunohistochemically.

Results

 c‐Fos and c‐Jun were detected 2 h after ligation and the expression of these two proteins reached a maximum after 4 h, becoming undetectable 16 h after ligation. The expressions of c‐Fos and c‐Jun were strongly correlated (r=0.9854, P<0.001). The expressions were of c‐Myc and Ki‐67 antigen was not detected within 24 h after ureteric ligation. The amount of rough endoplasmic reticulum (rER) in the ligated ureters increased soon after complete ligation and the increase continued throughout the period of ureteric obstruction (r=0.9699, P<0.001). The change in rER was also significantly correlated with the expression of c‐Fos and c‐Jun within 8 h after ligation.

Conclusion

 The expression of c‐Fos and c‐Jun, but not c‐Myc, might contribute to the hypertrophy of the ureteric smooth muscle layer during the course of complete ureteric obstruction. There is no hyperplasia in ureteric smooth muscle in the early stages of obstructive uropathy.
Conventional or Li vasectomy: a questionnaire study
Authors: SKRIVER M. , SKOVSGAARD F. , MISKOWIAK J.
Published: November 2003

Objective

 To compare pain, discomfort, complications and convalescence during and after vasectomy performed conventionally or using the Li ‘no‐scalpel’ method.

Patients and methods

 Between March 1993 and May 1995, 256 men were vasectomized at two city hospitals in Copenhagen; half of the patients underwent the conventional technique at one hospital and the remaining half the Li method at the other. The two groups were matched for the time at which they underwent surgery and therefore for the duration of follow‐up. A questionnaire was sent to all patients, in which they scored pain and discomfort using a 10 cm visual analogue scale (VAS). The reproducibility of measurements was tested on 10 patients who had answered the same questions 1.5–2 years earlier.

Results

 Men vasectomized using the Li method experienced less pain at rest after the first week (P=0.05) and less use of analgesics (P<0.001), had fewer infections (P=0.0015) and contacts with their physician (P=0.0078) than those conventionally vasectomized. There were no significant differences between the groups for pain and discomfort during surgery and in the first week after vasectomy, frequency of bleeding, haematoma, oedema, granuloma, pain at activity, absence from work, vasectomy failure by sperm analysis, sexual activity and satisfaction with the cosmetic result (all P>0.05).

Conclusion

 Vasectomy using the Li method reduced post‐operative pain, the use of analgesics, the frequency of infections and contacts with a physician when compared with the conventional procedure.
Diverticula of the female urethra
Authors: FORTUNATO P. , SCHETTINI M. , GALLUCCI M.
Published: November 2003

Objective

 To determine the optimum procedure for the diagnosis and therapy of diverticula of the female urethra.

Patients and methods

 The study included 18 patients with urethral diverticula treated at the Cristo Re Hospital in Rome between 1987 and 1995. Most of the patients were suffering from cystitis (eight), dysuria (seven) and recurring urinary infections (11). Less frequently, more specific symptoms were present such as post‐voiding dribbling (two) and anterior vaginal mass (three). The pre‐operative evaluation included a history, physical examination, voiding and positive pressure voiding cysto‐urethrography (VCUG) and urodynamic tests. A ‘typical’ surgical excision of the diverticula was carried out in all cases. Surgical excision was combined with cystopexis (Raz operation) in four patients with urinary stress incontinence and three with detrusor instability were treated post‐operatively with anticholinergics for 3 months. The outcome was evaluated by a physical examination and urodynamic tests at 3, 6 and 12 months post‐operatively; the mean (range) follow‐up was 34 (2–80) months.

Results

 All the urethral diverticula were in the distal two‐thirds of the urethra, along the posterolateral wall. The VCUG was sufficient for diagnosis in eight patients while the other 10 required a positive‐pressure VCUG. Fifteen patients were evaluated; complications included a urinary tract infection for 2 months in four patients and stress incontinence for 2 months in two. There were no recurrences or urethrovaginal fistulae.

Conclusions

 Diverticula in the female urethra are difficult to diagnose because the symptoms can be misleading; the positive‐pressure VCUG is useful in doubtful cases. However, a detailed history and physical examination are mandatory.
Free and total prostate‐specific antigen serum concentrations do not help to detect prostate cancer in patients with urinary outlet obstruction
Authors: TRYGG G. , POUSETTE Å. , EKENGREN J. , HAHN R.G.
Published: November 2003

Objectives

 To determine whether different molecular forms of prostate‐specific antigen (PSA) obtained before transurethral resection of the prostate (TURP) indicate the presence of prostate cancer.

Patients and methods

 The free, total and free‐to‐total PSA levels were measured in 261 patients scheduled for TURP, 20 of whom had known prostate cancer. The tissue histology was compared with the PSA levels and the patients were followed for 5 years.

Results

 Prostate cancer was detected in 23 of the patients (9%) who were thought to have benign disease. Normal ranges for the distribution of the PSA levels were established based on the patients with a benign histology, but these ranges did not detect most of the unknown cancers. The sensitivity of the total PSA test in detecting cancer was 38% and the specificity 90%. The discrimination was no better when considering the free fraction or the free‐to‐total PSA level. However, none of the 14 patients whose cancer was missed showed general progression of the disease during the 5‐year follow‐up and only one died from prostate cancer. In contrast, eight of the 20 patients with a known prostatic malignancy showed general progression, and six died from the disease.

Conclusion

 PSA testing of patients with outlet obstruction often failed to detect prostate cancer, but the prognosis was moderately good in those patients in whom it was missed.
Does necrosis on frozen‐section analysis of a mass after chemotherapy justify a limited retroperitoneal resection in patients with advanced testis cancer?
Authors: HERR H.W.
Published: November 2003

Objective

 To evaluate morbidity and relapse in patients with advanced testis cancer who underwent a post‐chemotherapy resection of a residual mass and a limited retroperitoneal lymph node dissection.

Patients and methods

 A total of 62 patients underwent complete resection of retroperitoneal masses after chemotherapy and a limited lymph node dissection if frozen sections of the mass showed necrosis (37 patients) or a bilateral dissection if the frozen section indicated viable germ cell tumour or teratoma (25 patients).

Results

 With a median follow‐up of 6 years, 14 (23%) patients relapsed, but only one within the retroperitoneum (teratoma) after a limited lymphadenectomy. There was a concordance of 89% between the frozen section of the post‐chemotherapy mass and the permanent‐section histological diagnosis of the entire lymphadenectomy specimen. Of the 37 patients whose masses showed necrosis on frozen section, three had viable germ cell tumour and one had teratoma on final histology. In all four false‐negative cases, residual tumour was confined to the resected mass. Six patients (10%) had surgical complications (one after limited and five after bilateral lymph node dissection).

Conclusion

 The surgical resection of all residual masses after chemotherapy, followed by limited retroperitoneal lymphadenectomy if frozen‐section analysis shows necrosis, is a safe approach in selected patients with advanced testicular cancer.
Paediatric ureteroscopy for ureteric calculi: a 4‐year experience
Authors: AL BUSAIDY S.S. , PREM A.R. , MEDHAT M.
Published: November 2003

Objective

 To study the efficacy and safety of ureteroscopy in the management of paediatric ureteric calculi at various levels.

Patients and methods

 The records of 50 ureteroscopic procedures performed on 43 children (age range 6 months‐12 years) for primary ureteric calculi or ureteric fragments after electrohydraulic shockwave lithotripsy (EHWL) were analysed retrospectively. The distribution of the calculi was in nine in the upper upper, seven in the mid and 30 in the lower ureter, with a mean stone burden of 1.26 cm. Ureteroscopy was performed with the 8.5/9.5/11.5 F Wolf ureteroscopes, and EHL was used as the primary method of fragmentation. Intravenous urograms were available in 34 children (79%) and micturating cystography (MCUG) was performed in 23 children (54%) during the follow‐up.

Results

 An overall stone‐free status was achieved in 40 children (93%) after performing 47 ureteroscopies (94%). Stones were completely cleared in 78%, 100% and 97% of the procedures in the upper, mid and lower ureters, respectively. In three children the procedure failed and they were salvaged by ureterolithotomy. During the procedures, an upper ureteric perforation occurred in one patient and a lower perforation in another. MCUG revealed low grade vesico‐ureteric reflux in 17% of the patients, but close follow‐up showed the reflux to be sterile and clinically insignificant.

Conclusion

 Ureteroscopy was safe and effective for the management of mid and lower ureteric calculi but the results for upper ureteric calculi were marginally inferior. Ureteroscopy must be performed judiciously to minimize ureteric injury in children. The incidence of vesico‐ureteric reflux after mechanical dilatation of the intramural ureter was infrequent and clinically insignificant.
Prognostic value of Ki‐67 antigen and p53 protein in urinary bladder cancer: immunohistochemical analysis of radical cystectomy specimens
Authors: Tsuji M. , Kojima K. , Murakami Y. , Kanayama H. , Kagawa S.
Published: November 2003

Objective To investigate the role of tumour proliferation and p53 expression as a marker of survival in patients with urinary bladder cancer who undergo radical cystectomy.

Patients and methods Samples were obtained from 31 patients (29 men and two women, mean age 66.0 years, range 46–80) with transitional cell carcinoma of the bladder who underwent radical cystectomy. The 31 formalin‐fixed radical cystectomy specimens were stained immunohistochemically for Ki‐67 antigen and p53 protein using MIB1 and p53 antibodies, respectively, and the results correlated with tumour grade, stages and prognosis.

Results The Ki‐67 index was significantly greater in high‐grade tumours and in those overexpressing p53 (>20% positive nuclei). Patients whose tumour samples had a high Ki‐67 index (>32%) had a significantly worse prognosis than those with a lower index (P<0.01). There was a similar correlation between Ki‐67 index and prognosis in high‐risk patients (grade 3 and pT3–4; P<0.05). Although the associations between tumour grade, stage and p53 expression were not statistically significant, patients whose tumour samples overexpressed p53 had a lower survival rate (P<0.05). No patients with tumours having a low Ki‐67 and low p53 index (n=14) died of urinary bladder cancer during the follow‐up.

Conclusion These results suggest that immunohistochemical analyses for Ki‐67 and p53 are useful prognostic indicators in patients with urinary bladder cancer who undergo radical cystectomy; the prognostic role of these markers was particularly important in high‐risk (grade 3 and pT3–4) patients.
Alpha‐receptor blockade for benign prostatic hyperplasia: uses and problems in a developing country
Authors: Ogbonna B.C. , Okeahialam B.N. , Ramyil V.M.
Published: November 2003

Objective  To evaluate the use and problems of alpha‐receptor blockade with prazosin among patients in Nigeria with benign prostatic hyperplasia (BPH) who face a prolonged wait for a prostatectomy.

Patients and methods  The study comprised 31 patients (mean age 64.4 years, range 55–89) facing a prolonged wait for prostatectomy: in group 1, 14 patients presented in acute urinary retention and had an indwelling urethral catheter; in group 2, six patients had indwelling catheters but removal was deemed necessary to control urinary tract infection; in group 3, 11 patients had troublesome symptoms from BPH but no retention. Some of the patients were also hypertensive. After receiving 1 mg of prazosin twice daily, the catheters were removed at various intervals and the effect on symptom scores and residual urine volume determined after one week and 2 months.

Results  Prazosin allowed the catheters to be removed, improved the symptoms of prostatism and/or controlled high blood pressure in seven, five and nine patients in each group, respectively.

Conclusion  The use of this alpha blocker for BPH in the absence of facilities to measure urinary flow rate, intravesical pressure and serum prostate specific antigen can be justified for short periods. However, a large default rate among these patients raises additional questions about long‐term safety and underlines the importance of selecting patients carefully.
Bowel problems after enterocystoplasty
Authors: Singh G. , Thomas D.G.
Published: November 2003

Objectives To document the changes in bowel habit in patients who have undergone enterocystoplasty.

Patients and methods Sixty‐nine patients with neuropathic (NP) and 44 with non‐neuropathic (NNP) bladder dysfunction (mean age 26 years, range 13–61, 93.6% socially continent), followed for at least 36 months after cystoplasty, were assessed using a questionnaire addressing faecal frequency, consistency, method of evacuation and incontinence episodes before and after surgery.

Results Of the patients with NP bladder dysfunction, 26 (38%) had more and seven (10%) less frequent bowel action after surgery, with 36 (52%) unchanged; 38 (55%) of patients had unchanged consistency, 26 (38%) were looser and five (7%) more constipated; 41 (59%) opened their bowels as before, 16 (23%) needed more help and 12 (17%) less help to evacuate; 16 (23%) patients had more and 17 (25%) less episodes of incontinence; 21 (30%) patients felt their bowels had not become normal after their operation and only 24 (35%) that they had returned to normal within 3 months of their operation. The bowel segment used was ileum in 44 patients, ileocaecal in 11 and sigmoid cystoplasty in 14. Patients with intact ileum did not have the same degree of diarrhoea, with only three of the 14 patients with a sigmoid cystoplasty being adversely affected. Of the patients with NNP bladder dysfunction, 18 patients (41%) had a more and five (11%) a less frequent bowel action; 20 (46%) had more loose and five (11%) less loose bowel action; similar numbers (five and four) needed either an increase or a decrease in laxatives or enemata; surprisingly, 12 patients (27%) felt they had an increase in the episodes of incontinence; 17 (39%) patients felt their bowels returned to normal within 3 months of surgery and 30% felt their bowels had not become normal after surgery. Only one patient in this group had a sigmoid cystoplasty and she did not find that the operation interfered with her bowel function.

Conclusions Ileal resection results in malabsorption of bile acids, maldigestion of fat and an imbalance of water and electrolytes. Patients with neurogenic bladders are finely balanced between acceptable bowel function and chaos, and surgery often tips this balance the wrong way. In 30% of the present patients, bowel problems persisted after surgery, with 38% having increased frequency, 38% having looser consistency and 23% more incontinence episodes following surgery. More surprisingly, a high percentage of NNP patients had bowel problems after cystoplasty.
Expression of bcl‐2 and p53 oncoproteins in schistosomiasis‐associated transitional and squamous cell carcinoma of urinary bladder
Authors: Chaudhary K.S. , Lu Q.L. , Abel P.D. , Khandan Nia N. , Shoma A.M. , El Baz M.A. , Stamp G.W.H. , Lalani E.N.
Published: November 2003

Objectives  To analyse the expression of bcl‐2 and p53 proteins in schistosomiasis‐associated bladder cancer compared to adjacent urothelium showing morphological alteration including hyperplasia, metaplasia and dysplasia.

Materials and methods  Twenty‐two formalin‐fixed and paraffin‐embedded samples of histologically confirmed schistosomiasis‐associated bladder tumours were assessed for grade, pathological stage (pT category) and the presence of hyperplasia, metaplasia and dysplasia in adjacent mucosa. There were 11 transitional cell carcinomas (TCCs), 10 squamous cell carcinomas (SCCs) and one diffuse infiltrating (signet‐ring cell type) adenocarcinoma. Epithelial hyperplasia was observed in seven cases and metaplasia in 18, most of which were squamous except for a single case of glandular metaplasia. Focal dysplastic areas were observed in eight cases. Sections were stained immunohistochemically for the expression of bcl‐2 and p53 proteins.

Results  Immunoreactivity for bcl‐2 was present in seven of 22 cases (four SCCs and three TCCs) of which three cases (two SCCs and one TCC) were strongly positive, but in contrast to previous studies, there was no increase in the poorly differentiated tumours. bcl‐2 was absent in metaplastic and dysplastic epithelium (except in a single case of glandular metaplasia) but it was present at low levels in basal cells of morphologically normal or hyperplastic transitional epithelium in 15 of 22 cases. Nine of 11 TCCs and seven of 10 SCCs showed p53 nuclear immunoreactivity. Heterogenous weak to moderate immunoreactivity for p53 was seen in 13 of 18 cases of metaplasia and in seven of eight cases of dysplasia in the mucosa adjacent to tumours. p53 was absent in normal and hyperplastic urothelium. Co‐expression of p53 and bcl‐2 was only seen in well differentiated areas of three tumours (two SCCs and one TCC).

Conclusion  This study detected the expression of bcl‐2 in a subset of bladder cancers (32%), whereas most (72%) of the tumours expressed immunoreactive p53. Additionally, p53 was also detected in metaplastic and dysplastic epithelium. Over‐expression of both p53 and bcl‐2 in the same tumour was only evident in a minority of schistosomiasis‐associated cancers (13%). There was no inverse relationship of p53 and bcl‐2 immunoreactivity.
Stimulation of α1‐adrenoceptors in the rat medial prefrontal cortex increases the local in vivo 5‐hydroxytryptamine release: reversal by antipsychotic drugs
Authors: Amargós‐Bosch Mercè , Adell Albert , Bortolozzi Analía , Artigas Francesc
Published: November 2003

Pyramidal neurons of the medial prefrontal cortex (mPFC) project to midbrain serotonergic neurons and control their activity. The stimulation of prefrontal 5‐HT2A and AMPA receptors increases pyramidal and serotonergic cell firing, and 5‐hydroxytryptamine (5‐HT) release in mPFC. As the mPFC contains abundant α1‐adrenoceptors whose activation increases the excitability of pyramidal neurons, we examined the effects of their stimulation on local 5‐HT release, using microdialysis. The application of the α1‐adrenoceptor agonist cirazoline by reverse dialysis increased the prefrontal 5‐HT release in a concentration‐dependent manner, an effect antagonized by coperfusion of TTX, prazosin (α1‐adrenoceptor antagonist), BAY × 3702 (5‐HT1A agonist), NBQX (AMPA/KA antagonist) and 1S,3S‐ACPD (mGluR II/III agonist), but not by MK‐801 (NMDA antagonist). Cirazoline also enhanced the increase in 5‐HT release induced by DOI (5‐HT2A/2C agonist) and AMPA. In addition, M100907 (5‐HT2A antagonist) but not SB‐242084 (5‐HT2C antagonist) reversed the cirazoline‐ and AMPA‐induced 5‐HT release. These results suggest that the stimulation of prefrontal α1‐adrenoceptors activates pyramidal afferents to ascending serotonergic neurons. The effect of cirazoline was also reversed by coperfusion of classical (chlorpromazine, haloperidol) and atypical (clozapine, olanzapine) antipsychotics, which suggests that a functional antagonism of the α1‐adrenoceptor‐mediated activation of prefrontal neurons may partly underlie their therapeutic action.
Lysophosphatidic acid induces process retraction in CG‐4 line oligodendrocytes and oligodendrocyte precursor cells but not in differentiated oligodendrocytes
Authors: Dawson John , Hotchin Neil , Lax Sian , Rumsby Martin
Published: November 2003

Lysophosphatidic acid is a growth factor‐like signalling phospholipid. We demonstrate here that lysophosphatidic acid induces process retraction in central glia‐4 cells and oligodendrocyte precursors. This lysophosphatidic acid effect is rapid and concentration‐dependent and results in cell rounding. It is inhibited by pre‐treatment of cells with C3 exoenzyme, a specific inhibitor of Rho, or with Y‐27632, a specific inhibitor of ROCK, a downstream kinase of Rho. Processes of differentiated central glia‐4 oligodendrocytes were insensitive to lysophosphatidic acid treatment but cell bodies became phase dark, indicating cell spreading on the poly‐l‐lysine substratum. RT‐PCR and Western blot analyses indicate that oligodendrocyte precursors and mature oligodendrocytes express mRNA and protein for LPA1, one of several LPA receptors. Thus lysophosphatidic acid may be signalling to Rho and stimulating actomyosin contraction in precursor oligodendrocytes by this family of receptors. The results show that lysophosphatidic acid signalling pathways influence retraction of processes in oligodendrocyte precursors but that this effect changes as oligodendrocytes differentiate.
Major Vault Protein, a Marker of Drug Resistance, Is Upregulated in Refractory Epilepsy
Authors: Sisodiya Sanjay M. , Martinian Lillian , Scheffer George L. , Valk Paul van der , Cross J. Helen , Scheper Rik J. , Harding Brian N. , Thom Maria
Published: November 2003

Summary:  Purpose: The molecular basis of drug resistance in epilepsy is being explored. Two proteins associated with drug resistance in cancer, P‐glycoprotein and multidrug resistance–associated protein 1, are upregulated in human epileptogenic pathologies. Other proteins associated with resistance in cancer include major vault protein (MVP) and breast cancer resistance protein (BCRP). We hypothesized that these proteins would also be upregulated in human epileptogenic pathologies.

Methods: Hippocampal sclerosis (HS), focal cortical dysplasia (FCD), and dysembryoplastic neuroepithelial tumor (DNT) were studied by using immunohistochemistry for MVP and BCRP. Nonepileptogenic control and histologically normal brain adjacent to epileptogenic tissue were used for comparison.

Results: MVP and BCRP were expressed ubiquitously in brain capillary endothelium. Ectopic upregulation of MVP was seen in hilar neurons in HS, dysplastic neurons in FCD, and lesional neurons in DNT. Only in HS cases were rare extralesional neurons immunoreactive. Glial upregulation was not seen. There was no qualitative upregulation of BCRP.

Conclusions: These results show that more than one resistance protein may be upregulated in a given epileptogenic pathology and may contribute to drug resistance. Determination of the types, amounts, and distribution of such proteins will be necessary for rational treatment for drug resistance in epilepsy.
THE TYCHOPELAGIC DIATOM, PARALIA SULCATA, AS PALEOINDICATOR SPECIES IN COASTAL MARINE ENVIRONMENTS
Authors: McQuoid M.R.
Published: November 2003

Paralia sulcata is a diatom commonly found in both the plankton and benthos of coastal environments. This species is heavily silicified and, thus preserves well in sedimentary records making it a potentially useful paleoindicator species. However, its tychopelagic nature and its association with a wide range of environmental conditions have made detailed paleoecological interpretations complicated. High‐resolution sediment records from coastal fjords in both Canada and Sweden show variations in the abundance and morphology of P. sulcata that provide evidence of changes in benthic habitat distribution and surface water properties in the fjords on timescales of decades to centuries. These studies suggest that P. sulcata can be an important paleoindicator species when interpretations are made in the context of its complex ecology.
SPECIES‐SPECIFIC RESPONSE IN ALKALINE PHOSPHATASE ACTIVITY OF FRESHWATER PHYTOPLANKTON IN A NUTRIENT ENRICHMENT EXPERIMENT
Authors: Rengefors K. , Haupert C. , Ruttenberg K.C. , Taylor C. , Howes B. L. , Anderson
Published: November 2003

A new method was utilized to study species‐specific responses of phytoplankton to phosphorus limitation in a nutrient enrichment experiment. A substrate, ELF, produces a fluorescent precipitate at the sites of alkaline phosphatase (AP), which makes it possible to visually detect phosphorus (P) limitation in individual cells of multiple species. Lake water was incubated in the laboratory to induce nitrogen (N) or P limitation. Initially, little or no ELF labeling was observed for any of the phytoplankton species, indicating a general lack of P limitation. This observation was supported by low bulk AP activity in the initial field samples. During the experiment, several chlorophyte taxa (Coelastrum, Eudorina, a solitary spiny coccoid) were driven to P limitation, as evidenced by a high percentage of cells displaying ELF labeling when inorganic N was added. Taxa such as Actinastrum and Dictyosphaerium, on the contrary, were never P limited. Little or no ELF was observed in cyanobacterial species, suggesting that P limitation was not achieved in these organisms. Using traditional bulk AP activity, significantly higher levels of AP activity were observed in treatments with inorganic N additions, compared to those with phosphate additions. ELF labeling generally followed the trend of bulk AP, except in species that did not dominate the biomass. Finally, we noted that all species observed were ELF labeled at least on one occasion, except for fragile flagellates which did not withstand the labeling procedure.
THE EFFECT OF SEAWEED DIETS ON GROWTH OF GREEN ABALONE, HALIOTIS FULGENS, FROM BAJA CALIFORNIA, MEXICO
Authors: Serviere‐Zaragoza E. , Mazariegos‐Villareal A. , Ponce‐Díaz G.
Published: November 2003

Two abalone species: green Haliotis fulgens and yellow Halioti corrugata represent nearly 97% of the total production in the Mexican abalone fishery. It has been assumed that abalone feed on the kelp algae Macrocystis pyrifera. Regional hatcheries use this species as a main source of natural food. M. pyrifera does not occur at the southern limit of the distribution of abalone species along the Baja California Peninsula. In this study, growth rates of juveniles H. fulgens, 17.3 ± 2.2 mm shell length and 0.4 ± 0.2 g body weight, were evaluated. Juveniles were fed with common species in the benthic environments inhabited by abalone along the western coast of Baja California during 191 days. Three diets were based on algae: palm kelp, Eisenia arborea, giant kelp, M. pyrifera and Gelidium robustum, and one on seagrass, Phyllospadix torreyi. Shell length and body growth rates varied between 21.5 μm day−1 and 2.2 mg day−1 for E. arborea and between 45.9 μm day−1 and 6.7 mg day−1 for M. pyrifera. Higher specific growth rates (SGR) in length and weight were determined for M. pyrifera: 0.2% and 0.7% day−1. Significant differences between values of juveniles fed M. pyrifera with the rest of the diets were found. The highest mortality (21%) was in juveniles fed the red algae G. robustum.
BIOGEOGRAPHY OF ASEXUAL AND SEXUAL REPRODUCTION IN CALOGLOSSA (DELESSERIACEAE, RHODOPHYTA) FROM AUSTRALIA AND NEW ZEALAND
Authors: West J. , Kamiya M. , Zuccarello G.
Published: November 2003

Caloglossa species are widely distributed in mangroves and salt marshes around the world and their life history patterns are being investigated in laboratory culture. In Australia all isolates of C. monosticha, C. postiae and C. ogasawaraensis have Polysiphonia‐type (P‐type) sexual life histories. Among the 70 C. leprieurii isolates from Australia and New Zealand P‐type sexual reproduction also is dominant. However, ten isolates of C. leprieurii from the Spencer Gulf and the Gulf of St. Vincent in South Australia give rise to successive tetrasporphyte generations without gametophytes. Moreover, one isolate from Queensland is asexual. Only one South Australia isolate, obtained from Lake Alexandrina at the mouth of the Murray River, is sexual. South Australia and Pacific Mexico are two regions in which asexual reproduction is dominant. In another mangrove dwelling red alga Bostrychia moritiziana (Rhodomelaceae) non‐sexual reproduction also is frequent in Australia, New Caledonia and Bali (Indonesia). This asexual reproductive pattern of tetrasporophytic recycling appears to have arisen independently among individual populations of various red algal species in different regions. Investigations are underway on the molecular phylogeny of the Caloglossa leprieurii isolates.
ALGAE AS USEFUL TOOLS IN CELLULOSE RESEARCH
Authors: Brown R. M.
Published: November 2003

This presentation will review the 1976 discovery of the enzyme complex in cellulose biosynthesis in Oocystis apiculata. A linear terminal complex (TC) was found to be associated with a microfibril, and from other freeze fracture applications, TCs have been found in many different algal genera. In fact, the algae have the most diverse and complex TCs among all organisms. TC diversity in terms of the evolution of cellulose biogenesis will be discussed. Combining the latest information from biochemistry and molecular genetics, the multiplicity of cellulose biogenesis will be reviewed. Cellulose molecular weight, crystalline structure, and mode of glycosylation for polymer formation all indicate that cellulose biogenesis is an extremely complex process. Major questions still remain, and the enzymes for cellulose biosynthesis have yet to be crystallized and their structure elucidated; however, the wealth of new information on cellulose structure and biosynthesis from algae to vascular plants, including bacteria and tunicates, all point to a very exciting and useful area of research. The algae have played key roles in our understanding of nature's most abundant macromolecule.
FRESHWATER DINOFLAGELLATES OF BELIZE, C.A.
Authors: Carty S.
Published: November 2003

Freshwater dinoflagellates have not previously been reported from Belize, although there has been extensive work with marine dinoflagellates and some work with other freshwater groups. Freshwater dinoflagellates are more frequently observed in standing water and none have been observed in the several streams and rivers sampled since 1990. The goal in 1998 was to examine water samples from small ponds within hours of collection to improve the chance of observing swimming dinoflagellates. A plankton net was used and whole water samples also were collected. A small brown water pond on a peninsula and 30m from the Caribbean yielded a bloom of Thompsodinium intermedium. Dinoflagellates, including Peridinium centenniale, Katodinium sp., and Peridinium sp. in the Umbonatum Group, were observed within “Crocodile pond” and “Lily pond” on the mainland.
MACROALGAL TISSUE NUTRIENTS AS INDICATORS OF NITROGEN AND PHOSPHORUS STATUS IN THE FLORIDA KEYS
Authors: Hanisak  , Siemon L.W.
Published: November 2003

This study used the tremendous biochemical and ecological diversity of macroalgae to assess nitrogen and phosphorus availability at a broad, ecosystem‐level scale in the Florida Keys and nearby waters. Spatial variation in tissue nutrients (carbon, C; nitrogen, N; phosphorus, P) of dominant macroalgae were assessed, both as ratios and absolute values, along 12 inshore‐offshore transects in the Florida Keys and at 10 stations in nearby Florida Bay. The resulting detailed analysis demonstrated spatial and temporal patterns in macroalgal tissue nutrients. The transect data revealed no universal inshore‐offshore patterns in tissue nutrients and no obvious “hotspots” of nutrient enrichment. Similarly, when data were compared among segments, there was no universal geographical pattern in tissue nutrients for all species. The most striking result was that the N and P status of macroalgae in Florida Bay was significantly different than other locations. Macroalgae collected from Florida Bay generally had higher N and lower P levels than algae collected elsewhere. The most common inshore‐offshore pattern was higher %N and lower %P availability inshore; however, limited inshore‐offshore differences in N:P ratio suggests that both nutrients were generally readily available in proportional amounts required by the various species. Most species in this study had higher %N, and to a lesser extent, higher %P and %C in March than in July. Based on the published literature on other species of macroalgae, it appears that N and P are generally available in sufficient quantities that most macroalgal growth is not limited by either nutrient.
Cardiac Magnetic Resonance (CMR) Imaging: A Noninvasive Tool for Functional and Morphological Assessment of Coronary Artery Disease:
Authors: PAETSCH INGO , GEBKER ROLF , FLECK ECKART , NAGEL EIKE
Published: November 2003

(J Interven Cardiol 2003;16:457–463)
Retarding field energy analyzer for the JET plasma boundary
Authors: Pitts R. A. , Chavan R. , Davies S. J. , Erents S. K. , Kaveney G. , Matthews G. F. , Neill G. , Vince J. E. ,   JET-EFDA workprogramme contributors, Duran I.
Published: October 2003

Retarding field analyzers (RFAs) are essentially the only practical tool with which to measure the distribution of ion energies in the boundary plasma of magnetic fusion devices. The technique has long been attempted in such facilities with varying degrees of success, but, by virtue of the delicate nature of these material probes and the hostile environment in which they are inserted, its use has been limited to smaller plasma machines with easier access and more tolerable plasma conditions. This article describes in detail a new RFA probe head recently constructed and tested on the large JET tokamak facility and now being used for plasma physics studies. Emphasis is placed on the details of design and mechanical construction as they relate to the particularly harsh conditions imposed both by the JET boundary plasma and the requirement that the probe be used to sample this plasma by insertion via a multiple plunge, fast reciprocating drive system. Some preliminary physics results are also included demonstrating both successful operation of the new device and discussing its limitations.
Small Asian‐owned retail businesses in the UK: an exploratory investigation
Authors: Chaudhry Shiv , Crick Dave
Published: October 2003

This paper investigates the importance of cultural factors within ethnic minority‐owned firms’ business practices. In doing so, it provides a contribution to the growing body of knowledge at the marketing/entrepreneurship interface and reports specifically on an empirical investigation into the retail marketing practices within a sample of Asian‐owned small firms operating in the UK. The findings from 20 in‐depth personal interviews provide an insight into the practices of ethnic minority‐owned retail businesses indicating that factors associated with key decision makers together with cultural networks, balanced against resource constraints, had a major impact on firms’ operations. Strategies used by the firms in order to enable them to survive in a competitive environment are identified and these contribute to knowledge by questioning the relevance of “break‐out theory” to ethnic minority‐owned firms.
Strategic interactive marketing of wine – a case of evolution
Authors: Quinton Sarah , Harridge‐March Sally
Published: October 2003

With the rapid evolution of technology and the changing pattern of wine purchase, providers need to consider the adoption of technology by consumers and hence how this impacts on strategic marketing planning. This paper tracks the evolution of Internet marketing of wine in the UK and focuses on whether wine providers currently use the Internet as a fundamental ingredient of their marketing strategy or whether the Internet is purely employed tactically. The authors present evidence that the wine sector is under‐utilising the potential of the Internet as part of an integrated marketing strategy and proposes that a customer‐oriented computer interface is required.
The advertising agency manager’s response patterns to a mail survey and follow‐ups
Authors: Zafer Erdogan B. , Tagg Stephen
Published: October 2003

This study reports findings about British advertising agency managers’ response patterns to a mail survey and four follow‐up techniques (original, photocopy, postcard and letter), which were manipulated to determine their individual impact on response rate. Findings should provide original insights to mail survey researchers planning to sample advertising agency managers in reducing both non‐response and sampling bias. The initial response rate was just over 18 per cent and four follow‐up techniques altogether lifted the overall response rate to a little less than 32 per cent. There are several statistically significant differences of importance to mail researchers in reducing non‐response bias and increasing response rate.
Explaining Split-Ticket Voting at the 1979 and 1997 General and Local Elections in England
Authors: Railings Colin , Thrasher Michael
Published: November 2003

Only in 1979, 1997 and 2001 have British general elections coincided with the annual local government elections. Uniquely, this study uses both survey and aggregate data to examine aspects of split-ticket voting at the simultaneous elections in 1979 and 1997. Through the use of bi- and multi-variate analysis, it suggests that ticket-splitting is a product of both voter attitudes and party strategies: although it is almost wholly confined to the less partisan, the electoral context in which those votes are being cast can play an additional and significant role in stimulating such behaviour.
First Views of the Depths
Authors: Berggren William A.
Published: November 2003

The Silent Landscape
The Scientific Voyage of HMS
Challenger
.
By Richard Corfield
. Joseph Henry Press (National Academies Press), Washington, DC, 2003. 299 pp. $24.95, C$34.95. ISBN 0-309-08904-2.

Drawing on the official records and the journals of the ship's scientists, officers, and crew, Corfield recounts the story of the
Challenger
's three-and-a-half-year, 69,000-nautical mile journey. He also discusses the expedition's scientific findings in the context of subsequent research in oceanography, marine geology, and ecology.
Microaerophilic Cooperation of Reductive and Oxidative Pathways Allows Maximal Photosynthetic Membrane Biosynthesis in
Rhodospirillum rubrum
Authors: Grammel Hartmut , Gilles Ernst-Dieter , Ghosh Robin
Published: November 2003

The purple nonsulfur bacterium
Rhodospirillum rubrum
has been employed to study physiological adaptation to limiting oxygen tensions (microaerophilic conditions).
R. rubrum
produces maximal levels of photosynthetic membranes when grown with both succinate and fructose as carbon sources under microaerophilic conditions in comparison to the level (only about 20% of the maximum) seen in the absence of fructose. Employing a unique partial O
2
pressure (pO
2
) control strategy to reliably adjust the oxygen tension to values below 0.5%, we have used bioreactor cultures to investigate the metabolic rationale for this effect. A metabolic profile of the central carbon metabolism of these cultures was obtained by determination of key enzyme activities under microaerophilic as well as aerobic and anaerobic phototrophic conditions. Under aerobic conditions succinate and fructose were consumed simultaneously, whereas oxygen-limiting conditions provoked the preferential breakdown of fructose. Fructose was utilized via the Embden-Meyerhof-Parnas pathway. High levels of pyrophosphate-dependent phosphofructokinase activity were found to be specific for oxygen-limited cultures. No glucose-6-phosphate dehydrogenase activity was detected under any conditions. We demonstrate that NADPH is supplied mainly by the pyridine-nucleotide transhydrogenase under oxygen-limiting conditions. The tricarboxylic acid cycle enzymes are present at significant levels during microaerophilic growth, albeit at lower levels than those seen under fully aerobic growth conditions. Levels of the reductive tricarboxylic acid cycle marker enzyme fumarate reductase were also high under microaerophilic conditions. We propose a model by which the primary “switching” of oxidative and reductive metabolism is performed at the level of the tricarboxylic acid cycle and suggest how this might affect redox signaling and gene expression in
R. rubrum
.
Diffusional Properties of Methanogenic Granular Sludge:
1
H NMR Characterization
Authors: Lens Piet N. L. , Gastesi Rakel , Vergeldt Frank , van Aelst Adriaan C. , Pisabarro Antonio G. , Van As Henk
Published: November 2003

The diffusive properties of anaerobic methanogenic and sulfidogenic aggregates present in wastewater treatment bioreactors were studied using diffusion analysis by relaxation time-separated pulsed-field gradient nuclear magnetic resonance (NMR) spectroscopy and NMR imaging. NMR spectroscopy measurements were performed at 22°C with 10 ml of granular sludge at a magnetic field strength of 0.5 T (20 MHz resonance frequency for protons). Self-diffusion coefficients of H
2
O in the investigated series of mesophilic aggregates were found to be 51 to 78% lower than the self-diffusion coefficient of free water. Interestingly, self-diffusion coefficients of H
2
O were independent of the aggregate size for the size fractions investigated. Diffusional transport occurred faster in aggregates growing under nutrient-rich conditions (e.g., the bottom of a reactor) or at high (55°C) temperatures than in aggregates cultivated in nutrient-poor conditions or at low (10°C) temperatures. Exposure of aggregates to 2.5% glutaraldehyde or heat (70 or 90°C for 30 min) modified the diffusional transport up to 20%. In contrast, deactivation of aggregates by HgCl
2
did not affect the H
2
O self-diffusion coefficient in aggregates. Analysis of NMR images of a single aggregate shows that methanogenic aggregates possess a spin-spin relaxation time and self-diffusion coefficient distribution, which are due to both physical (porosity) and chemical (metal sulfide precipitates) factors.