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1.
Rev. Assoc. Med. Bras. (1992) ; 67(1): 64-70, Jan. 2021. tab, graf
Article in English | LILACS | ID: biblio-1287776

ABSTRACT

SUMMARY OBJECTIVE: Bladder cancer under the age of 40 is extremely rare. Bladder cancer development involves complex and multi-stage processes, one of which is the DNA damage repair mechanism. In this retrospective study, we aimed to evaluate the histopathological features of bladder urothelial carcinoma seen in patients under 40 years of age and tumor microsatellite instability status using immunohistochemistry. METHODS: A total of 50 patients under the age of 40 with urothelial bladder carcinoma from two different centers in the same country were included. Expression of the mismatch repair proteins MLH1, MSH2, MSH6, and PMS2 was analyzed by immunohistochemistry. RESULTS: Age at the time of diagnosis ranged from 17 to 40 years old. Most tumors were non-invasive papillary urothelial carcinoma. Two cases had nuclear loss of MSH-6 and PMS-2. We observed that tumor grade, tumor stage, presence of tumor differentiation, and infiltrative growth pattern of the tumor have significant impact on prognosis, but microsatellite instability does not have an effective role in bladder carcinogenesis in young patients. CONCLUSIONS: Our results indicate that the presence of microsatellite instability is not related to the low tumor grade and stage in urothelial neoplasms in young patients, suggesting that urothelial carcinoma of the bladder in young patients may represent a genetically stable form of neoplasia.


Subject(s)
Humans , Adolescent , Adult , Young Adult , Carcinoma, Transitional Cell/genetics , Microsatellite Instability , Urinary Bladder/metabolism , Retrospective Studies , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , DNA Mismatch Repair
2.
Chinese Medical Journal ; (24): 935-943, 2021.
Article in English | WPRIM | ID: wpr-878142

ABSTRACT

BACKGROUND@#Since 2019, a novel coronavirus named 2019 novel coronavirus (2019-nCoV) has emerged worldwide. Apart from fever and respiratory complications, acute kidney injury has been observed in a few patients with coronavirus disease 2019. Furthermore, according to recent findings, the virus has been detected in urine. Angiotensin-converting enzyme II (ACE2) has been proposed to serve as the receptor for the entry of 2019-nCoV, which is the same as that for the severe acute respiratory syndrome. This study aimed to investigate the possible cause of kidney damage and the potential route of 2019-nCoV infection in the urinary system.@*METHODS@#We used both published kidney and bladder cell atlas data and new independent kidney single-cell RNA sequencing data generated in-house to evaluate ACE2 gene expression in all cell types in healthy kidneys and bladders. The Pearson correlation coefficients between ACE2 and all other genes were first generated. Then, genes with r values larger than 0.1 and P values smaller than 0.01 were deemed significant co-expression genes with ACE2.@*RESULTS@#Our results showed the enriched expression of ACE2 in all subtypes of proximal tubule (PT) cells of the kidney. ACE2 expression was found in 5.12%, 5.80%, and 14.38% of the proximal convoluted tubule cells, PT cells, and proximal straight tubule cells, respectively, in three published kidney cell atlas datasets. In addition, ACE2 expression was also confirmed in 12.05%, 6.80%, and 10.20% of cells of the proximal convoluted tubule, PT, and proximal straight tubule, respectively, in our own two healthy kidney samples. For the analysis of public data from three bladder samples, ACE2 expression was low but detectable in bladder epithelial cells. Only 0.25% and 1.28% of intermediate cells and umbrella cells, respectively, had ACE2 expression.@*CONCLUSION@#This study has provided bioinformatics evidence of the potential route of 2019-nCoV infection in the urinary system.


Subject(s)
Humans , Angiotensin-Converting Enzyme 2/metabolism , COVID-19 , Gene Expression , Kidney/metabolism , SARS-CoV-2 , Sequence Analysis, RNA , Single-Cell Analysis , Urinary Bladder/metabolism
3.
Acta cir. bras ; 31(1): 44-52, Jan. 2016. tab, graf
Article in English | LILACS | ID: lil-771852

ABSTRACT

PURPOSE: To study the expression of HER2, p53 and Ki67 proteins in cystoplasties. METHODS: Sixty rats were distributed randomly into three groups of 20 animals. Bladder augmentation was held to increase with ileum (Group I), colon (Group II) and stomach (Group III). Tissue samples of neobladder was collected from each rat to its own control. The animals were sacrificed after 12 weeks. The neobladder was withdrawn for immunohistochemitry analysis of p53, HER2 and Ki67 expression. Wilcoxon and Mann-Whitney tests were used for statistical study. RESULTS: There were no significant changes in the expression of p53 and HER2 proteins. It was observed significant increase (p<0.0001) in Ki67 expression in all groups, when compared with their respective controls. When the study groups were compared with each other, there was increase of cell proliferation in the largest gastrocystoplasties in respect of ileocystoplasties (p=0.004) and colocystoplasties (p=0.003). CONCLUSION: We observed significant increase of cell proliferation characterized by Ki67 protein in the digestive tract of the ileocystoplasties, the colocystoplasties and the gastrocystoplasties and this increase was significantly greater in gastrocystoplasties.


Subject(s)
Animals , Colon/metabolism , Ileum/metabolism , /metabolism , Lower Gastrointestinal Tract/surgery , /metabolism , Stomach/metabolism , /metabolism , Urinary Bladder/surgery , Colon/transplantation , Immunohistochemistry , Ileum/transplantation , Lower Gastrointestinal Tract/metabolism , Rats, Wistar , Statistics, Nonparametric , Stomach/transplantation , Urinary Bladder/metabolism
4.
Journal of Korean Medical Science ; : 280-285, 2016.
Article in English | WPRIM | ID: wpr-225579

ABSTRACT

Na+/K+-ATPase (NKA) is abundantly expressed in the basolateral membrane of epithelial cells, which is necessary for tight junction formation. The tight junction is an urothelial barrier between urine and the underlying bladder. Impairment of tight junctions allows migration of urinary solutes in patients with interstitial cystitis/painful bladder syndrome (IC/PBS). We evaluated NKA expression and activity in bladder samples from patients with IC/PBS. The study group consisted of 85 patients with IC/PBS, and the control group consisted of 20 volunteers. Bladder biopsies were taken from both groups. We determined the expression and distribution of NKA using NKA activity assays, immunoblotting, immunohistochemical staining, and immunofluorescent staining. The protein levels and activity of NKA in the study group were significantly lower than the control group (1.08 ± 0.06 vs. 2.39 ± 0.29 and 0.60 ± 0.04 vs. 1.81 ± 0.18 micromol ADP/mg protein/hour, respectively; P < 0.05). Additionally, immunofluorescent staining for detection of CK7, a marker of the bladder urothelium, predominantly colocalized with NKA in patients in the study group. Our results demonstrated the expression and activity of NKA were decreased in bladder biopsies of patients with IC/PBS. These findings suggest that NKA function is impaired in the bladders from patients with IC/PBS.


Subject(s)
Adult , Female , Humans , Male , Middle Aged , Cystitis, Interstitial/diagnosis , Fluorescent Antibody Technique , Keratin-7/metabolism , Microscopy, Fluorescence , Sodium-Potassium-Exchanging ATPase/metabolism , Urinary Bladder/metabolism , Urothelium/metabolism
5.
Einstein (Säo Paulo) ; 13(3): 404-409, July-Sep. 2015. tab, graf
Article in English | LILACS | ID: lil-761957

ABSTRACT

Objective To re-examine the function of the urinary bladder in vivoas well as to determine the functional and biochemical characteristics of bladder muscarinic receptors in long-term alloxan-induced diabetes rats.Methods Two-month-old male Wistar rats were injected with alloxan and the animals showing blood glucose levels >300mg/dL together with age-paired untreated animals were kept for 11 months. Body weight, bladder weight, blood glucose, and urinary volume over a period of 24 hours were determined in both groups of animals. A voiding cystometry in conscious control and diabetic rats was performed to determine maximal micturition pressure, micturition contraction interval and duration as well as voided and post-voiding residual volume. In addition, concentration-response curves for bethanechol in isolated bladder strips, as well as [3H]-N methyl-scopolamine binding site characteristics in bladder homogenates were determined.Results Mean bladder weight was 162.5±21.2mg versus 290±37.9mg in control and treated animals, respectively (p<0.05). Micturition contraction amplitude (34.6±4.7mmHg versus 49.6±2.5mmHg), duration (14.5±1.7 seconds versus 23.33±4.6 seconds) and interval (87.5±17.02 seconds versus 281.11±20.24 seconds) were significantly greater in alloxan diabetic rats. Voided urine volume per micturition contraction was also significantly higher in diabetic animals. However the post-voiding residual volume was not statistically different. Bethanechol potency (EC50 3µM versus 5µM) and maximal effect (31.2±5.9g/g versus 36.1±6.8g/g) in isolated bladder strips as well as number (169±4fmol/mg versus 176±3fmol/mg protein) and affinity (0.69±0.1nM versus 0.57±0.1nM) of bladder muscarinic receptors were also not statistically different.Conclusion Bladder function in vivo is altered in chronic alloxan-induced diabetes rats without changes in functional and biochemical characteristics of bladder muscarinic receptors.


Objetivo Reestudar o funcionamento da bexiga in vivo e determinar as características funcionais e bioquímicas dos receptores muscarínicos vesicais de ratos com diabetes crônico induzido por aloxana.Métodos Ratos Wistar de dois meses de idade receberam injeção de aloxana, e os animais que apresentaram glicemia >300mg/dL foram mantidos por 11 meses junto de outros não tratados e pareados por idade. Nos dois grupos de animais, peso corpóreo, peso da bexiga, glicemia e volume urinário de 24 horas foram medidos. Em ambos os grupos, realizou-se a cistometria miccional em animais não anestesiados. Foram determinados os seguintes parâmetros: pressão máxima de micção, intervalo e contração de micção, bem como o volume de esvaziamento e o volume residual pós-miccional. Além disso, foram determinadas as curvas de concentração-resposta a betanecol em preparações isoladas de bexiga e também as características dos sítios de ligação da [3H]-N-metil-escopolamina em homogenatos de bexiga.Resultados O peso médio da bexiga foi de 162,5±21,2mg versus290±37,9mg nos animais controles e tratados, respectivamente (p<0,05). A amplitude de contração (34,6±4,7mmHg versus 49,6±2,5mmHg), a duração (14,5±1,7 segundos versus 23,33±4,6 segundos) e o intervalo (87,5±17,02 segundos versus 281,11±20,24 segundos) de micção foram significantemente maiores nos ratos tratados com aloxana. O volume de urina eliminada durante a contração miccional também foi maior nos animais diabéticos. Contudo, o volume residual pós-miccional não foi estatisticamente diferente. Não foram observadas diferenças na resposta ao betanecol (EC50 3µM versus 5µM) e no seu efeito máximo (31,2±5,9g/g versus 36,1±6,8g/g) em preparações isoladas de bexiga, bem como no número total (169±43fmol/mgversus 176±3fmol/mg) e na afinidade (0,69±0,1nMversus 0,57±0,1nM) dos receptores muscarínicos da bexiga.Conclusão O funcionamento da bexiga in vivo está alterado no diabetes crônico induzido por aloxana, porém sem alterações funcionais e bioquímicas nos receptores muscarínicos da bexiga.


Subject(s)
Animals , Male , Diabetes Mellitus, Experimental/metabolism , Receptors, Muscarinic/metabolism , Urinary Bladder/metabolism , Alloxan/administration & dosage , Bethanechol/administration & dosage , Disease Models, Animal , Dose-Response Relationship, Drug , Diabetes Mellitus, Experimental/chemically induced , Muscle Contraction/drug effects , Muscle Contraction/physiology , N-Methylscopolamine/administration & dosage , Rats, Wistar , Receptors, Muscarinic/drug effects , Time Factors , Urinary Bladder/drug effects , Urinary Bladder/physiopathology , Urination/drug effects , Urination/physiology
6.
Biocell ; 35(3): 71-79, Dec. 2011. tab
Article in English | LILACS | ID: lil-653213

ABSTRACT

Apigenin, a nonmutagenic flavonoid, has been shown to possess free radical scavenging activities, anticarcinogenic properties, antioxidant and anti-inflammatory effects. Recently, apigenin was reported to cause gastric relaxation in murine. To assess possible effects of apigenin on migration of bladder smooth muscle (SM) cell, we isolated SM cells from peri-cancer tissue of human bladder and established a cell model that was capable to overexpress transiently MEKK1 (MEK kinase 1). Results showed that overexpression of active human MEKK1 by adenoviruses infection induced migration of human bladder smooth muscle (hBSM) cells and phosphorylation of MAPKs, ERK, JNK and p38, which are the downstream molecules of MEKK1. Then, hBSM cell overexpressing MEKK1 were exposed to apigenin (50 microM). Our data indicated that apigenin inhibited significantly activation/phosphorylation of MAPKs and migration of hBSM cells induced by MEKK1 overexpression. Besides, apigenin inhibited actin polymerization, which underlines muscle contraction and cell migration. The results suggest that apigenin inhibits activation of MAPKs and thereby the cell migration. The mechanism might be that apigenin blocks signal transmission from MEKK1 to MAPKs.


Subject(s)
Humans , Animals , Rats , Apigenin/pharmacology , Flavonoids , MAP Kinase Kinase Kinase 1/metabolism , Myocytes, Smooth Muscle , Myocytes, Smooth Muscle/metabolism , Cell Movement , Urinary Bladder , Urinary Bladder/metabolism , Cells, Cultured , Phosphorylation , Immunoblotting , MAP Kinase Kinase Kinase 1/genetics , Mitogen-Activated Protein Kinases/metabolism
7.
Journal of Korean Medical Science ; : 814-823, 2011.
Article in English | WPRIM | ID: wpr-58117

ABSTRACT

The influence of spinal cord injury (SCI) on protein expression in the rat urinary bladder was assessed by proteomic analysis at different time intervals post-injury. After contusion SCI between T9 and T10, bladder tissues were processed by 2-DE and MALDI-TOF/MS at 6 hr to 28 days after SCI to identify proteins involved in the healing process of SCI-induced neurogenic bladder. Approximately 1,000 spots from the bladder of SCI and sham groups were visualized and identified. At one day after SCI, the expression levels of three protein were increased, and seven spots were down-regulated, including heat shock protein 27 (Hsp27) and heat shock protein 20 (Hsp20). Fifteen spots such as S100-A11 were differentially expressed seven days post-injury, and seven proteins including transgelin had altered expression patterns 28 days after injury. Of the proteins with altered expression levels, transgelin, S100-A11, Hsp27 and Hsp20 were continuously and variably expressed throughout the entire post-SCI recovery of the bladder. The identified proteins at each time point belong to eight functional categories. The altered expression patterns identified by 2-DE of transgelin and S100-A11 were verified by Western blot. Transgelin and protein S100-A11 may be candidates for protein biomarkers in the bladder healing process after SCI.


Subject(s)
Animals , Female , Rats , Biomarkers/metabolism , Electrophoresis, Gel, Two-Dimensional , HSP20 Heat-Shock Proteins/metabolism , HSP27 Heat-Shock Proteins/metabolism , Microfilament Proteins/metabolism , Muscle Proteins/metabolism , Proteome/biosynthesis , Proteomics , Rats, Sprague-Dawley , S100 Proteins/metabolism , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Spinal Cord Injuries/metabolism , Urinary Bladder/metabolism , Wound Healing
8.
Int. braz. j. urol ; 35(3): 315-325, May-June 2009. tab
Article in English | LILACS | ID: lil-523157

ABSTRACT

OBJECTIVE: To assess the role of transforming growth factor-β1 (TGF-β1) in congenital ureteropelvic junction obstruction at diagnosis and during postoperative follow-up. MATERIAL AND METHODS: We conducted a case-control study including 19 patients with a mean age of 6.7 years and 19 matched controls. All patients presented negative voiding cystourethrography, obstructive diuretic renogram and underwent dismembered pyeloplasty. Urinary TGF-β1 and other markers were measured pre-, intra- and postoperatively. RESULTS: The mean bladder urine TGF-β1 concentration in obstructed patients prior to pyeloplasty was higher than in controls (92.5 pg/mL ± 16.8 vs. 35.8 pg/mL ± 16.2; p = 0.0001). The mean renal pelvic urine TGF-β1 concentration in the hydronephrotic kidney was higher than in the preoperative bladder urine sample (122.3 pg/mL ± 43.9 vs. 92.5 pg/mL ± 16.8; p = 0.036). Postoperative mean TGF-β1 concentration was significantly lower than preoperative TGF-β1 (48.7 pg/mL ± 13.1 vs. 92.5 pg/mL ± 16.8; p = 0.0001). CONCLUSION: TGF-β1 is a cytokine leading to renal fibrosis. The measurement of urinary TGF-β1 could become a useful tool for the diagnosis of obstructive hydronephrosis and the evaluation of the parenchyma function status, pre and postoperatively.


Subject(s)
Child , Female , Humans , Male , Hydronephrosis/diagnosis , Transforming Growth Factor beta1/urine , Ureteral Obstruction/diagnosis , Biomarkers/urine , Case-Control Studies , Follow-Up Studies , Hydronephrosis/urine , Kidney Pelvis , Perioperative Period , Sensitivity and Specificity , Treatment Outcome , Ureteral Obstruction/congenital , Ureteral Obstruction/surgery , Ureteral Obstruction/urine , Urinary Bladder/metabolism , Vesico-Ureteral Reflux/diagnosis
9.
Int. braz. j. urol ; 35(1): 76-83, Jan.-Feb. 2009. ilus, graf, tab
Article in English | LILACS | ID: lil-510266

ABSTRACT

Purpose: We investigated the presence of functional ß1, ß2 and ß3-adrenoceptor in urothelium and detrusor muscle of human bladder through in vitro pharmacology of selective ß3 adrenoceptor agonist solabegron. Materials and Methods: Expression of these adrenoceptors in surgically separated human urothelium and detrusor muscle were investigated using RT-PCR. The effects of activating these receptors were studied by determining the relaxation produced by ß-adrenoceptors agonist in pre-contracted human detrusor strips. Results: The results confirmed the presence of mRNA for ß1, ß2 and ß3-adrenoceptor in both human urothelium and detrusor. In an in vitro functional bladder assay, Solabegron and other agonists for ß-adrenoceptors such as procaterol and isoproterenol evoked potent concentration-dependent relaxation of isolated human bladder strips with pD2 values of 8.73 ± 0.19, 5.08 ± 0.48 and 6.28 ± 0.54, respectively. Conclusions: Selective ß3-adrenoceptor agonist may be a potential new treatment for the overactive bladder OAB syndrome. Existence of ß3-adrenoceptor mRNA exists in the urothelium in addition to the detrusor muscle suggest multiple site of actions for the ß3-adrenoceptor in the lower urinary tract.


Subject(s)
Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Young Adult , Adrenergic beta-Agonists/pharmacology , Aniline Compounds/pharmacology , Benzoates , /agonists , Urinary Bladder/drug effects , Urothelium/drug effects , Dose-Response Relationship, Drug , Muscle, Smooth/drug effects , Reverse Transcriptase Polymerase Chain Reaction , Receptors, Adrenergic, beta-1/agonists , Receptors, Adrenergic, beta-1/genetics , /genetics , /agonists , /genetics , Urinary Bladder/metabolism , Urothelium/metabolism , Young Adult
10.
Journal of Korean Medical Science ; : 684-689, 2009.
Article in English | WPRIM | ID: wpr-170151

ABSTRACT

Even though uroplakins (UPs) are believed to serve a strong protective barrier against toxic materials, cyclophosphamide (CP) causes extensive cystitis. We investigated the expression of UPs in the urothelium in CP induced mouse cystitis. A total of 27 ICR female mice received a single intraperitoneal injection of 200 mg CP/kg. Nine CP-treated mice and 6 controls were sequentially killed at 12, 24, and 72 hr post injection. Extensive cystitis and an increased vesical weight were seen. These all peaked within 12 hr post injection and they tended to decrease thereafter. The level of all the UPs mRNA, the protein expressions of UP II and III on immunoblotting study, and the expression of UP III on immunolocalization study were maximally suppressed within 12 hr; this partially recovered at 24 hr, and this completely recovered at 72 hr post CP injection. In conclusion, CP reduced the expression of UPs. The reduction of the UPs mRNA and protein was time dependent, and this peaked within 12 hr after CP injection. However, the damage was rapidly repaired within 24 hr. This study demonstrates a dynamic process, an extensive reduction and rapid recovery, for the UPs expression of the mouse urinary bladder after CP injection.


Subject(s)
Animals , Female , Mice , Cyclophosphamide/toxicity , Cystitis/chemically induced , Immunosuppressive Agents/toxicity , Membrane Glycoproteins/metabolism , Membrane Proteins/metabolism , Mice, Inbred ICR , RNA, Messenger/metabolism , Time Factors , Urinary Bladder/metabolism
11.
Journal of Korean Medical Science ; : 497-501, 2007.
Article in English | WPRIM | ID: wpr-109313

ABSTRACT

Innovative replacement of incontinence surgery (IRIS) is a polypropylene tape that is placed beneath the midurethra to restore urinary continence. We evaluated the long-term efficacy and safety of the IRIS procedure and compared it with tensionfree vaginal tape (TVT) for the treatment of female stress urinary incontinence. We included all 66 consecutive women who underwent IRIS (n=34) or TVT (n=32) between February 2002 and April 2003 and followed them up for at least 3 yr postoperatively. The 3-yr success rate was 94.1% for the IRIS and 93.8% for the TVT, and the satisfaction rates were 91.2% and 90.6%, respectively. Intraoperative complications for the IRIS group included 3 cases of bladder perforation, and there were 3 cases of bladder perforation in the TVT group. The postoperative complications for the IRIS group included 2 patients with de novo urgency and one patient with mesh erosion. Three patients with TVT developed de novo urgency. One case of each group showed temporary voiding difficulty. On the basis of our results, the IRIS may be an effective and safe procedure as compared to TVT, with a high success rate and a low complication rate.


Subject(s)
Adult , Female , Humans , Middle Aged , Body Mass Index , Follow-Up Studies , Suburethral Slings , Time Factors , Treatment Outcome , Urinary Bladder/metabolism , Urinary Incontinence, Stress/surgery , Urologic Surgical Procedures/methods
12.
Journal of Korean Medical Science ; : 1000-1005, 2005.
Article in English | WPRIM | ID: wpr-63478

ABSTRACT

We investigated the pathophysiological mechanism by proteomic approach as a possible tool to detect the marker proteins to develop lower urinary tract symptoms following bladder outlet obstruction (BOO). Rats were randomized into 3 groups; control, sham operation and BOO groups. BOO group was divided into 1, 3, and 5 day-group. Conventional proteomics was performed with high resolution 2-D gel electrophoresis followed by computational image analysis and protein identification using mass spectrometry using rat urinary bladders. A comparison of bladder of BOO group with control bladder showed that three proteins of optineurin, thioredoxin and preprohaptoglobin were over-expressed in the bladder of BOO group. In addition, four proteins, such as peroxiredoxin 2, transgelin, hippocampal cholinergic neurostimulating peptide (HCNP) and beta-galactoside-binding lectin, were under-expressed in the bladder of BOO group. These data supported that downregulation of HCNP might make detrusor muscle be supersensitive to acetylcholine, up-regulation of optineurin means the protection of nerve injury, and down-regulation of transgelin means the decreased contractility of detrusor muscle. Beside these proteins, other proteins are related to oxidative stress or have a nonspecific function in this study. However more information is needed in human bladder tissue for clinical usage.


Subject(s)
Animals , Female , Rats , Urinary Bladder/metabolism , Urinary Bladder Neck Obstruction/genetics , Down-Regulation , Electrophoresis, Gel, Two-Dimensional , Gene Expression , Proteins/genetics , Proteomics , Rats, Sprague-Dawley , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Up-Regulation
13.
J Environ Biol ; 2004 Oct; 25(4): 431-6
Article in English | IMSEAR | ID: sea-113350

ABSTRACT

A highly sensitive sodium (Na+) transfer tissue biosensor (STTB) was designed using a frog bladder membrane to measure paralytic shellfish poisons (PSP). The STTB consists, of a Na+ electrode covered by the membrane, which was then integrated into a flow-through system for continuous measurements. In the absence of Na+ channel blocker, active transfer of Na+ occurred from inside to outside across the frog membrane. When the STTB was used to measure the Na+ -dependent dissociation of PSP, it was able to detect PSB at a level contained in a single cell. However, 5 fg or higher (100 cells or more) is needed for accurate and reproducible measurements. The toxicity obtained by the STTB was significantly correlated (r = 0.9449) to that determined by the HPLC. Therefore, the simple method of the STTB can be used not only to detect a low level PSP in toxic plankton populations, but also to monitor poisons in shellfish.


Subject(s)
Animals , Anura , Biological Transport, Active/physiology , Biosensing Techniques , Chromatography, High Pressure Liquid , Dinoflagellida/chemistry , Environmental Monitoring/methods , Marine Toxins/analysis , Membranes/metabolism , Saxitoxin/analogs & derivatives , Sodium/metabolism , Tetrodotoxin/analysis , Urinary Bladder/metabolism
14.
Journal of Korean Medical Science ; : 701-706, 2003.
Article in English | WPRIM | ID: wpr-221852

ABSTRACT

We present accidental findings that potassium channel blockers, such as tetraethyl-ammonium (TEA) or 4-aminopyridine (4-AP), inhibit the sustained tonic contraction induced by carbachol in rat detrusor muscle strips. The relatively lower concentrations (5 mM) potentiated phasic contractions. The potentiation of phasic contraction was not observed in nicardipine pretreated condition. In nicardipine pretreated condition, the concentration-response curves for the negative inotropic effect of potassium channel blockers were shifted to the right by the increasing concentration of carbachol from 0.5 micrometer to 5 micrometer. IC50 was changed significantly from 0.19 to 0.64 mM (TEA) and from 0.21 to 0.96 (4-AP). Such inhibitory effects were also observed in Ca2+ depleted condition, where 0.1 mM EGTA and 1 micrometer thapsigargin were added into Ca2+ free solution. In conclusion, inhibitory effects of potasssium channel blockers on carbachol-induced contraction may be ascribed to the direct inhibition of receptor-agonist binding.


Subject(s)
Animals , Female , Male , Mice , Rabbits , Rats , 4-Aminopyridine/pharmacology , Urinary Bladder/metabolism , Calcium/chemistry , Calcium Channel Blockers/pharmacology , Carbachol/pharmacology , Dose-Response Relationship, Drug , Guinea Pigs , Inhibitory Concentration 50 , Muscle Contraction/drug effects , Muscles/drug effects , Nicardipine/pharmacology , Potassium Channel Blockers/pharmacology , Protein Binding , Rats, Sprague-Dawley , Tetraethylammonium/pharmacology , Vasodilator Agents/pharmacology
15.
Indian J Biochem Biophys ; 1997 Feb-Apr; 34(1-2): 205-11
Article in English | IMSEAR | ID: sea-27741

ABSTRACT

The long-term objective of this study is to elucidate the role of bladder mucosal glycosaminoglycans and mucin glycoproteins in the development of interstitial cystitis and other bladder diseases. Bladder biopsies and urine samples from patients and healthy controls were analyzed for glycoconjugates by biochemical and immunochemical methods. Due to the limited availability of human bladders for research purposes, detailed analysis of rabbit bladders glycoconjugates were also carried out. Biochemical analysis of rabbit bladders indicate that while the major portion of the glycoconjugates in the urothelium is sialoglycoprotein, low levels of heparan sulfate and chondroitin sulfate are also present. The correlating immunohistochemical data show very weak staining of the rabbit bladder epithelium by antiglycosaminoglycan antibodies. In contrast, the lamina propria and muscle layers stained intensely for chondroitin sulfate and hyaluronic acid. Thus, the quantity of glycosaminoglycans associated with the bladder epithelial layer, particularly as extracellular matrix components on the luminal surface of the bladder, appears insignificant. On the other hand, several lectins and anti-epitectin (a MUC1 sialoglycoprotein) antibodies showed strong staining of the luminal surface of rabbit and normal human bladders. Further, preliminary results with anti-epitectin antibodies reveal a weaker and patchy staining of biopsy specimens from interstitial cystitis patients compared to controls. The urinary levels of glycosaminoglycans and epitectin, in interstitial cystitis patients and healthy controls were determined by chemical or immunoassays. Urinary epitectin, but not glycosaminoglycans, was decreased in interstitial cystitis patients.


Subject(s)
Animals , Antigens, Tumor-Associated, Carbohydrate/metabolism , Cystitis, Interstitial/etiology , Glycoconjugates/metabolism , Glycosaminoglycans/metabolism , Humans , Immunohistochemistry , Mucous Membrane/metabolism , Organ Culture Techniques , Rabbits , Urinary Bladder/metabolism
16.
Indian J Exp Biol ; 1991 Sep; 29(9): 831-6
Article in English | IMSEAR | ID: sea-57200

ABSTRACT

Electrokinetic studies namely hydrodynamic permeability, electroosmotic permeability and streaming potential measurements of aqueous solutions of oxalic acid and urea have been made across urinary bladder membranes of goat. Energy conversion maxima and degree of coupling for these permeants have computed. It has been found that these values increase with increases in concentration of the permeants. Since electro-osmotic flux tendency is quite opposite for oxalic acid in comparison to that of urea, energy conversion values increase with increase in concentration but in opposite directions. Such studies are expected to be of use in understanding electrophysiology of the bladder as inefficient functioning of the bladder leads to formation of urinary calculi and many other types of disorders. Methodology of non-equilibrium thermodynamics have been used to explain the data.


Subject(s)
Animals , Biological Transport , Cell Membrane/metabolism , Electrophysiology , Goats , Kinetics , Oxalates/metabolism , Oxalic Acid , Urea/metabolism , Urinary Bladder/metabolism
17.
Braz. j. med. biol. res ; 24(1): 123-6, jan.-mar. 1991. ilus
Article in English | LILACS | ID: lil-99591

ABSTRACT

Multichannel experiments were carried out to investigate the Ca2+ - induced down-regulation of epithelial Na+ channels reconstituted into planar lipid bilayer membranes. Reconstitution was achueved by fusion of vesiculated apical membrane fragments to solvent-free planar lipid bilayers. We found that the presence of micromolar concentrations of Ca2+ on the side to which the vesicles were added substantially lowered the channel-mediated current. The inhibition was strongly influenced by pH. At pH 8.0 all the current was blocked by 1 mM calcium, whereas at pH 7.1 the inhibition was about 80%. The blocking kinetics was clearly voltage-dependent. The mechanism of blocking cannot be explained either in terms of interations with a single site, or by a model in which two blocking sites are assumed.


Subject(s)
Animals , Amiloride/pharmacology , Calcium/physiology , Cell Membrane Permeability , Sodium/metabolism , Bufo marinus , Skin/metabolism , Urinary Bladder/metabolism
18.
Indian J Biochem Biophys ; 1990 Jun; 27(3): 179-82
Article in English | IMSEAR | ID: sea-27349

ABSTRACT

Efficiency of energy conversion for electro-osmosis and streaming potential and the degree of coupling of acids across urinary bladder membranes of goat have been computed using non-equilibrium thermodynamic theory. The energy conversion maxima and degree of coupling for acids responsible for the formation of urinary calculi are found to be much low as compared to urea and urine.


Subject(s)
Animals , Ascorbic Acid/urine , Aspirin/urine , Carboxylic Acids/urine , Citrates/urine , Citric Acid , Electrophysiology , Goats , Hippurates/urine , Membranes/metabolism , Oxalates/urine , Oxalic Acid , Urinary Bladder/metabolism
19.
Indian J Exp Biol ; 1990 Mar; 28(3): 221-7
Article in English | IMSEAR | ID: sea-59767

ABSTRACT

Electrokinetic studies of aqueous solutions of urea, glucose, urea-glucose mixture (urea concentration increasing and glucose fixed) and glucose-urea mixture (glucose concentration increasing and urea concentration fixed) have been carried out across urinary bladder membranes of goat. Results have been analysed using methodology of non-equilibrium thermodynamics. It has been found that energy conversion maxima and degree of coupling for mixtures is higher than urea and glucose solutions. It has also been found that in the case of urea-glucose mixtures, the value of maxima and degree of coupling first decreases and then increases with increase in concentration while in the case of glucose-urea mixture, the trend is not definite. With urea solutions only, both these values increase with increase in concentration. It has been observed that energy conversion maxima and degree of coupling for urine is much higher as compared to other permeants. It appears that second order phenomenological coefficient L112 is related with degree of coupling (qe) as the trend of two is quite similar.


Subject(s)
Animals , Cell Membrane/metabolism , Glucose/metabolism , Glycosuria/metabolism , Goats , Kinetics , Membrane Potentials , Models, Biological , Solutions , Urea/metabolism , Urinary Bladder/metabolism
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