bluuebunny/crossref_metadata_2025_split huggingface dataset:
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

AbstractPyramidal 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

AbstractLysophosphatidic 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.
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

ABSTRACT

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

ABSTRACT

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.