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Ohara K, Kono T, Chisato N, Asama T, Yoneda M, Kasai S. Acetic acid-derived prostaglandin-dependent colonic adaptive cytoprotection is preserved in chronic colitis: role of cyclo-oxygenase. Int J Colorectal Dis 2003; 18:260-6. [PMID: 12673493 DOI: 10.1007/s00384-002-0459-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/10/2002] [Indexed: 02/04/2023]
Abstract
BACKGROUND AND AIMS We recently reported the phenomenon of prostaglandin-dependent colonic adaptive cytoprotection (CAP) against acute colonic injury induced by acetic acid (AA) in the normal colon. This study investigated whether the CAP is preserved in the chronic inflamed colon. MATERIALS AND METHODS Normal rats and a chronic colitis model, induced by trinitrobenzene sulfonic acid, received an intracolonal administration (0.5 ml) of saline or AA at low concentration (1%) followed by high concentration (8%) 30 min later. The distal colon was removed 48 h after 8% AA administration, and colitis was assessed by macroscopic scoring and measurement of the myeloperoxidase (MPO) activity. Indomethacin (5 mg/kg), a nonselective cyclo-oxygenase (COX) inhibitor, or N-[2-cyclohexyloxy-4-nitrophenyl] methane-sulfonamide (NS398, 1 mg/kg), a COX type 2 selective inhibitor, was injected intraperitoneally 1 h before pretreatment with 1% AA. RESULTS Intracolonal administration of 8% AA induced colonic mucosal damage (macroscopic score 10.0+/-0.9) and elevated MPO activity (2.8+/-0.2 U/g), which were significantly reduced to 3.3+/-0.8 and 1.8+/-0.2 U/g by 1% AA pretreatment, respectively. Indomethacin abolished the gross mucosal protective effect by 1% AA pretreatment in 8% AA-derived colitis in normal rats while the NS398 had no effect. Both indomethacin and NS398 reversed the MPO activity reduction induced by 1% AA pretreatment. In chronic inflamed colon 8% AA treatment resulted in an increase in the macroscopic score to 11.5+/-0.4 from 4.7+/-0.4, but not the MPO activity, which was significantly reduced to 5.7+/-0.9 by 1% AA pretreatment. This gross mucosal protective effect by 1% AA pretreatment in chronic inflamed colon was reversed by indomethacin while the NS398 had no effect. CONCLUSION These data show that COX-1 and COX-2 derived prostaglandins induced by low concentration AA pretreatment reduce the colonic mucosal injury and the increase in the MPO activity in colitis, respectively. The protective effect of COX-1 is preserved in chronic inflamed colon. These findings support the existence of a low concentration of AA-derived prostaglandin-dependent CAP and suggest that colonic AA, which is derived from bacterial breakdown of carbohydrate and protein in the colon, plays a crucial role in the endogenous defense mechanisms.
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Chen S, Agarwal A, Glushakova OY, Jorgensen MS, Salgar SK, Poirier A, Flotte TR, Croker BP, Madsen KM, Atkinson MA, Hauswirth WW, Berns KI, Tisher CC. Gene delivery in renal tubular epithelial cells using recombinant adeno-associated viral vectors. J Am Soc Nephrol 2003; 14:947-58. [PMID: 12660329 DOI: 10.1097/01.asn.0000057858.45649.f7] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Gene therapy has the potential to provide a therapeutic strategy for numerous renal diseases such as diabetic nephropathy, chronic rejection, Alport syndrome, polycystic kidney disease, and inherited tubular disorders. In previous studies using cationic liposomes or adenoviral or retroviral vectors to deliver genes into the kidney, transgene expression has been transient and often associated with adverse host immune responses, particularly with the use of adenoviral vectors. The unique properties of recombinant adeno-associated viral (rAAV) vectors permit long-term stable transgene expression with a relatively low host immune response. The purpose of the present study was to evaluate gene expression in the rat kidney after intrarenal arterial infusion of a rAAV (serotype 2) vector encoding green fluorescence protein (GFP) induced by a cytomegalovirus-chicken beta-actin hybrid promoter. The left kidney of experimental animals was treated with either saline or transduced with rAAV2-GFP (0.125 ml/100 g body wt, 1 x 10(10)/ml infectious units) through the renal artery. A time-dependent expression of GFP was observed in all kidneys injected with rAAV2-GFP, with maximal expression observed at 6 wk posttransduction. The expression of GFP was restricted to cells in the S(3) segment of the proximal tubule and intercalated cells in the collecting duct, the latter identified by co-localization with H(+)-ATPase. No transduction was observed in the glomeruli or the intrarenal vasculature. These studies demonstrate successful transgene expression in tubular epithelial cells, specifically in the S(3) segment of the proximal tubule and intercalated cells, after intrarenal administration of a rAAV vector and provide the impetus for further studies to exploit its use as a tool for gene therapy in the kidney.
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Faneca H, Simões S, de Lima MCP. Evaluation of lipid-based reagents to mediate intracellular gene delivery. BIOCHIMICA ET BIOPHYSICA ACTA 2002; 1567:23-33. [PMID: 12488034 DOI: 10.1016/s0005-2736(02)00545-x] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
We characterized different cationic lipid-based gene delivery systems consisting of both liposomes and nonliposomal structures, in terms of their in vitro transfection activity, resistance to the presence of serum, protective effect against nuclease degradation and stability under different storage conditions. The effect of lipid/DNA charge ratio of the resulting complexes on these properties was also evaluated. Our results indicate that the highest levels of transfection activity were observed for complexes prepared from nonliposomal structures composed of FuGENE 6. However, their DNA protective effect was shown to be lower than that observed for cationic liposome formulations when prepared at the optimal (+/-) charge ratio. Our results suggest that lipoplexes are resistant to serum up to 30% when prepared at a 2:1 lipid/DNA charge ratio. However, when they were prepared at higher (+/-) charge ratios, they become sensitive to serum for even lower concentrations (10%). Replacement of dioleoyl-phosphatidylethanolamine (DOPE) by cholesterol enhanced the resistance of the complexes to the inhibitory effect of serum. This different biological activity in the presence of serum was attributed to different extents of binding of serum proteins to the complexes, as evaluated by the immunoblotting assay. Studies on the stability under storage show that lipoplexes maintain most of their biological activity when stored at -80 degrees C, following their fast freezing in liquid nitrogen.
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Ooya T, Yui N. Multivalent interactions between biotin-polyrotaxane conjugates and streptavidin as a model of new targeting for transporters. J Control Release 2002; 80:219-28. [PMID: 11943400 DOI: 10.1016/s0168-3659(02)00030-5] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Kinetic analysis of interactions between biotin-polyrotaxane or biotin-alpha-cyclodextrin (biotin-alpha-CD) conjugates and streptavidin was carried out as a model of new targeting to transporters using the surface plasmon resonance (SPR) technique. The biotin-polyrotaxane conjugates, in which biotin-introduced alpha-CDs are threaded onto a poly(ethylene oxide) chain capped with bulky end-groups, are expected to increase the valency of biotin from monovalent to multivalent binding. The number of biotins conjugated with one polyrotaxane molecule varied from 11 to 78, and apparently increased the association equilibrium constant (K(a)), assuming pseudo-first-order kinetics. A detailed dissociation kinetics was analyzed and the re-binding of the biotin-polyrotaxane conjugates was observed on the streptavidin-deposited SPR surface. The magnitude of the re-binding is likely to become larger with increasing the number of biotins, suggesting multivalent interaction on the SPR surface. To quantify the effect of valency, competitive inhibition assay was performed in terms of the supramolecular structure of the polyrotaxane. The inhibitory potency of the biotin-polyrotaxane conjugate was found to be 4-5 times greater than that of the biotin-alpha-CD conjugate. Therefore, the biotin-polyrotaxane conjugates by supramolecular formation of the biotin-alpha-CD conjugate significantly switches from monovalent to multivalent bindings to the model binding protein, streptavidin.
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Chao A, Lai CH, Hsueh S, Lin SM, Chang TC. Intralesional injection for hepatic metastasis from cervical carcinoma. A report of two cases. THE JOURNAL OF REPRODUCTIVE MEDICINE 2001; 46:1008-12. [PMID: 11762144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
BACKGROUND The treatment of isolated hepatic metastasis from carcinoma of the uterine cervix has yet to be established. We tested the efficacy of percutaneous injection of ethanol and acetic acid as a curative-intent treatment modality for this rare event. CASES Under real-time sonographic guidance, two patients with a solitary hepatic metastasis from carcinoma of the cervix were treated with 99.5% percutaneous ethanol injection (one patient) and 50% percutaneous acetic acid injection (the other patient). The treatment was repeated weekly if laboratory data permitted and aspiration cytology interpreted on site showed tumor cells. Cytology after complete treatment showed no residual tumor cells in either case. Both patients had no evidence of disease during follow-up for 12 and 24 months, respectively. CONCLUSION Treatment was successful in two patients with isolated hepatic metastatic lesions from carcinoma of the cervix who received percutaneous injection of 99.5% ethanol or 50% acetic acid.
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Singh V, Sehgal A, Parashari A, Sodhani P, Satyanarayana L. Early detection of cervical cancer through acetic acid application--an aided visual inspection. Singapore Med J 2001; 42:351-4. [PMID: 11764051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE To assess the sensitivity and specificity of visual inspection of cervix for detection of precancerous and early cancerous lesions of cervix. METHODS In a Maternal and Child Health Care setting of New Delhi women underwent a detailed pelvic examination, visual inspection of cervix after 5% acetic acid application, cytology (pap smear), detailed colposcopic examination and colposcopic directed biopsy when indicated. RESULTS Findings of aided visual inspection using 5% acetic acid and of cytology were evaluated among symptomatic 402 women against colposcopic findings and/or histologic reports. Seventy-three mild dysplasias, 50 moderate dysplasias, 45 severe dysplasias/Carcinoma in-situ and 40 early invasive cancerous cases were diagnosed histologically. The sensitivity of cytology (75.3%) was higher compared to that of acetic acid application (52.0%) for mild dysplasias. On the other hand, the sensitivity for detecting moderate dysplasias was 78% for cytology and 81.6% for acetic acid; for severe dysplasias/carcinoma in-situ it was 73.3% for cytology and 86.7% for acetic acid. For invasive cancers sensitivity for acetic acid application and cytology (95% for both modalities) was comparable. The specificity of cytology (99%) was higher compared to that of acetic acid application (94.3%). The false positive rate for cytology was 1.0% as against 5.7% for acetic acid application. The results of acetic acid application also showed a remarkable improvement in the sensitivity of unaided visual inspection for early cancerous lesion which was about 60% for early cancerous lesion and only 12% for mild dysplastic and 20% for moderate and severe dysplastic lesions in our earlier experience. It also reduced the false positive rates from 12% by unaided visual inspection to 5.7% by acetic acid application. Furthermore, cost of detection of one true lesion through acetic acid application (Rs.1689.00) was much lower as compared to the cost involved in cytology detected true lesions (Rs.2227.00). Visual inspection without acetic acid incurred Rs.6608.60 for detection of true lesion. CONCLUSION Screening for cervical precancerous and cancerous lesions using visual inspection aided by acetic acid may be a suitable low-cost and a feasible alternative modality for control of cervical cancer in a resource poor setting.
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Abstract
PURPOSE To investigate whether electroporation can be used for topical gene delivery and for DNA expression in rat keratinocytes. METHODS The localization of a fluorescent-labelled plasmid and the expression of a reporter gene (pEGFP-N1) coding for Green Fluorescent Protein (GFP) in stripped skin were assessed by Confocal Laser Scanning Microscopy (CLSM). RESULTS The plasmid penetrated into the epidermis within minutes after electroporation and entered the keratinocyte cytoplasm within hours. A localized expression of GFP was observed for at least 7 days in the epidermis. Skin viability was not compromised by electroporation. CONCLUSIONS Electroporation enhances the delivery, and hence the expression, of topically applied plasmid DNA on the skin. It could be a promising alternative method to administer DNA, particularly for DNA vaccines, in the skin in vivo.
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Nishida K, Nakakoga Y, Sato N, Kawakami S, Mukai T, Sasaki H, Sakaeda T, Nakamura J. Effect of viscous additives on drug absorption from the liver surface in rats using phenol red as a model. Eur J Pharm Biopharm 2000; 50:397-402. [PMID: 11072197 DOI: 10.1016/s0939-6411(00)00112-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The purpose of this study is to obtain information that can be used to improve controlled release and residence time of drugs on the liver surface. Using carboxymethylcellulose sodium salt (CMC-Na) and polyvinyl alcohol (PVA), we examined the effect of viscous formulations on the absorption of phenol red as a model. In the presence of 3% CMC-Na or 15% PVA, the maximum plasma concentration of phenol red decreased after application to the rat liver surface using a cylindrical glass cell. The absorption ratios in 6 h calculated from the remaining amount of phenol red in the glass cell were 68.6, 60.5 and 48.7% (control: 73.1%) in the presence of 1 or 3% CMC-Na and 15% PVA, respectively. As a result of the reduction in the absorption ratio, the amount of phenol red excreted into the bile and urine in 6 h was decreased by the addition of the viscous additives. The decrease in absorption rate was characterized by a pharmacokinetic analysis of the plasma concentration profile. The change in absorption rate differed between the viscous additives, reflecting the result of the in vitro release experiment. Accordingly, the possibility that the drug absorption rate from the liver surface can be altered by viscous additives was suggested to have a promising prospect for therapeutic use.
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Sudo E, Boyd WA, King M. Effects of dextran sulfate on tracheal mucociliary velocity in dogs. JOURNAL OF AEROSOL MEDICINE : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY FOR AEROSOLS IN MEDICINE 2000; 13:87-96. [PMID: 11010598 DOI: 10.1089/089426800418613] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We have shown that low molecular weight dextran, as a potential mucolytic agent, reduced the viscoelasticity and spinnability of cystic fibrosis (CF) sputum and improved its ciliary transportability in vitro; it also reduced viscoelasticity of healthy dog mucus in in vitro testing. In anesthetized dogs, dextran administered by aerosol at 65 mg/mL increased tracheal mucus velocity, but this increase was not sustained for higher concentrations. The purpose of the present study is to evaluate whether low mol. wt. dextran sulfate, a charged oligosaccharide, exhibits similar effects to previously tested neutral dextran when administered by aerosol to anesthetized dogs in terms of mucus rheology and mucociliary clearance rate. Healthy mongrel dogs were anesthetized with pentobarbital and intubated. Aerosols of Ringer's solution or dextran sulfate (m.w. 5000) dissolved in Ringer's were generated by Pari LC STAR nebulizer, and delivered during 30-min periods of spontaneous breathing. Tracheal transepithelial potential difference (PD, using agar filled electrodes) and tracheal mucociliary velocity (TMV, by charcoal marker particle transport) were measured under bronchoscopic control, and mucus for viscoelasticity analysis by magnetic rheometry was collected by the endotracheal tube method. We performed experiments in seven dogs, involving 30-min administrations of aerosol, separated by 30-min periods of no aerosol. All dogs received inhalations of 6.5 mg/mL, 20 mg/mL, and 65 mg/mL dextran sulfate. Tracheal mucus viscoelasticity (average log G* over 1-100 rad/s) decreased progressively with increasing dose of dextran sulfate; for the highest concentration (65 mg/mL), log G* decreased by a factor of 2.61 (p = 0.021). A modest increase in the TMV was observed for the first dose of dextran sulfate (128% of baseline at 6.5 mg/mL, p = 0.066); thereafter TMV was stable. PD increased significantly at each concentration of dextran sulfate compared with Ringer control; however, there was no additional change between the three groups. The solids content of collected airway fluid (%SC) was gradually increased during successive 30-min dextran sulfate aerosols, indicating a significant residence time for the dextran in the mucus, and correlating with the decrease in viscoelasticity. These results suggest that dextran sulfate may be potentially of therapeutic value as a mucolytic agent, assisting mucus clearance by cough and physiotherapy, although whether it stimulates mucociliary clearance remains to be proven.
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Yamauchi M, Kinoshita M, Sasanuma M, Tsuji S, Terada M, Morimyo M, Ishikawa Y. Introduction of a foreign gene into medakafish using the particle gun method. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 2000; 287:285-93. [PMID: 10951388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
We developed a procedure to introduce a foreign gene into fertilized eggs of medakafish (Oryzias latipes) using the particle gun method, which is one of the easiest and most reliable techniques for gene transfer. A plasmid construct with the green fluorescence protein (GFP) gene driven by the madakafish beta-actin gene promoter was successfully introduced into eggs, and the expression of GFP was observed in 20% of the primary transfectant (chimera) fish. In addition, germ line transmission of GFP was observed in 13% of the GFP-positive primary transfectant fish. The new application described here should enable us to investigate gene expression using the fish model on a routine basis without high technical sophistication. J. Exp. Zool. 287:285-293, 2000.
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Marcusson JA, Carlmark B, Jarstrand C. Mercury intolerance in relation to superoxide dismutase, glutathione peroxidase, catalase, and the nitroblue tetrazolium responses. ENVIRONMENTAL RESEARCH 2000; 83:123-128. [PMID: 10856185 DOI: 10.1006/enrs.1999.4030] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Through percutaneous provocation with metallic mercury and phenyl mercuric acetate in patients stating the presence of subjective psychosomatic symptoms following dental amalgam treatment, it has been possible to categorize and score two extreme groups of patients, mercury-intolerant and mercury-tolerant patients reacting and not reacting, respectively, to low doses of mercury. The intolerant patients had a high psychosomatic score and the tolerant patients had a low or null score when exposed to low doses of the two mercury compounds. Determination of the scavenger enzymes superoxide dismutase, glutathione peroxidase, and catalase showed no significant differences between the mercury-intolerant and the mercury-tolerant patients and the controls. The activity of superoxide dismutase and the quantitative psychosomatic score elicited by either metallic mercury or phenyl mercuric acetate showed a positive correlation. On the other hand, analyses of the psychosomatic score and the areas under the curves of the nitroblue tetrazolium test response showed negative correlations. The results indicate that the oxidative metabolism and, in particular, superoxide dismutase may be perturbed in mercury-intolerant patients.
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Nakamura J, Yoshida Y, Mera K, Mukai T, Nishida K, Sasaki H. Continuous microinstillation of phenol red on liver surface for liver site-selective delivery. Biol Pharm Bull 1999; 22:713-5. [PMID: 10443468 DOI: 10.1248/bpb.22.713] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We report a very promising approach for liver site-selective drug delivery through drug instillation on liver surface. Phenol red, which was selected as a model drug, was accumulated in the instillation site after instillation on the rat liver surface. The site-selective localization was enhanced by gradually and continuously instilling a small amount of drug solution on the liver surface.
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Velpandian T, Gupta SK, Gupta YK, Biswas NR, Agarwal HC. Ocular drug targeting by liposomes and their corneal interactions. J Microencapsul 1999; 16:243-50. [PMID: 10080117 DOI: 10.1080/026520499289211] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Topical drug delivery is preferred in the eye to avoid under or over medication and undesired side effects of systemic administration. In order to maintain adequate drug levels in ocular tissues, frequent drug installation is necessary in vision threatening conditions like glaucoma, corneal ulcers due to microbial infections, etc. Only a part of the installed drug reaches the aqueous humor and the rest of it is drained by the nasolacrimal duct. Positively charged liposomes have been found to enhance the penetration of drugs into the cornea. The present study was conducted to visualize the interaction of liposomes with the cornea. Briefly, positively charged liposomes entrapped with Carboxyfluorescein (CF), Propidium iodide (PI), Horseradish peroxidase (HRP), Biotin, Hydroxy benzimide (Hoechst No: 33258), and Ethoxy benzimide (Hoechst No: 33342) were prepared by sonication. Their size and shape were analysed by laser dynamic light spectra and electron microscopy, respectively. The liposome encapsulated and free materials in buffer were instilled, in a volume of 20 microliters, into eyes of anesthetized albino rats. After 30 min and 1 h, the eyes were enucleated and quickly processed for cryosections of 3-5 microns thickness. The interaction of liposome entrapped propidium iodide and HRP was visualized on the outer epithelium of the cornea after specific processing.
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Tanaka H, Habuchi Y, Nishio M, Suto F, Yoshimura M. Modulation by chloramine-T of 4-aminopyridine-sensitive transient outward current in rabbit atrial cells. Eur J Pharmacol 1998; 358:85-92. [PMID: 9809873 DOI: 10.1016/s0014-2999(98)00578-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The effects of an oxidizing agent, chloramine-T, on the 4-aminopyridine-sensitive transient outward current (ITO) were investigated in rabbit atrial myocytes by using patch-clamp techniques. Extracellular application of chloramine-T at 20 microM irreversibly slowed the time course of inactivation of the whole-cell ITO, and increased the peak by 19.3% (n = 19) at +40 mV. At 100 microM, chloramine-T decreased the peak by 22.5% (n = 9) of the control, and subsequently induced a glibenclamide-sensitive time-independent outward K+ current. Under superfusion with dithiothreitol (3 mM), chloramine-T (100 microM) produced no change in ITO. The chloramine-T-induced slowing of ITO inactivation was partially reversed by subsequent application of 3 mM dithiothreitol. In single-channel recordings with the cell-attached patch configuration, chloramine-T (20 microM) increased the open probability of the ITO channel from 0.15 to 0.46 at a potential 100 mV positive to the resting potential, and the mean open lifetime from 5.1 ms to 7.0 ms (n = 5). The unitary current amplitude was not affected. As a result, chloramine-T increased the ensemble current in amplitude and slowed its decay. These results indicated that: (1) inactivation of the native A-type channels of rabbit heart is susceptible to oxidation; and (2) oxidation of ITO channels may contribute to the genesis of arrhythmias.
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Vandoni RE, Cuttat JF, Wicky S, Suter M. CT-guided methylene-blue labelling before thoracoscopic resection of pulmonary nodules. Eur J Cardiothorac Surg 1998; 14:265-70. [PMID: 9761435 DOI: 10.1016/s1010-7940(98)00160-2] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
OBJECTIVE Evaluation of the efficiency of our technique of methylene-blue labelling of pulmonary nodules to facilitate thoracoscopic recognition and excision. DESIGN Patients with a peripheral pulmonary nodule smaller than 2.5 cm and not in contact with the visceral pleura were included. Under tomodensitometric guidance, the nodules were labelled with methylene-blue within hours before thoracoscopic wedge resection. If frozen section revealed a primary bronchial carcinoma, thoracotomy and classical resection were performed during the same anesthesia. RESULTS Between July 1992 and August 1996, 54 nodules were removed in 51 patients. Labelling was performed between 75 and 270 min before surgery and was complicated in 13 patients (25.4%) by a small pneumothorax without any clinical consequence. Labelling allowed successful thoracoscopic recognition of 50 nodules (92%) and thoracoscopic wedge resection was possible in all but one cases (91%). Five patients (9%) required thoracotomy. Histology showed a benign lesion in 22 cases, a primary lung carcinoma in 17 and a metastases in 15. Twenty of the 22 benign nodules (91%) were removed without thoracotomy. According to the protocol, 13 patients with a primary lung tumour underwent lobectomy during the same session. There was no mortality nor morbidity amongst patients who had thoracoscopy only. CONCLUSIONS Our technique of labelling peripheral pulmonary nodules with methylene-blue is very effective and is not associated with any relevant complication. Thoracoscopic excision and diagnosis is possible in more than 90% of the cases. We therefore recommend this simple, low-cost and reliable technique for nodules not in contact with the visceral pleura before thoracoscopic wedge resection.
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Hahn RG. Ethanol monitoring of fluid absorption in anesthesiology practice. J Clin Anesth 1998; 10:357-9. [PMID: 9702612 DOI: 10.1016/s0952-8180(98)00045-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Konrad C, Gerber HR, Schuepfer G, Schmucki O. Transurethral resection syndrome: effect of the introduction into clinical practice of a new method for monitoring fluid absorption. J Clin Anesth 1998; 10:360-5. [PMID: 9702613 DOI: 10.1016/s0952-8180(98)00046-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
STUDY OBJECTIVE To determine the effects of introduction of a new monitoring system for fluid absorption during transurethral resection of the prostate (TURP) using an irrigating solution containing 0.5% alcohol. STUDY DESIGN Prospective clinical investigation, with implementation of statistical process control. SETTING Inpatients for TURP at a major non-university teaching hospital. PATIENTS 312 male ASA physical status I, II, III, and IV patients scheduled for TURP. INTERVENTIONS Intraoperative breath alcohol levels were measured for detection of fluid absorption. MEASUREMENTS AND MAIN RESULTS Calculation of the amount of fluid absorbed using measured breath alcohol values. Process variability (i.e., numbers of patients with significant fluid absorption) was defined by statistical process control tools. No trend change of prevalence of fluid absorption was noted until 150 procedures had been completed. Reduction of prevalence of significant fluid absorption was noted and no patients were treated postoperatively in the intensive care unit. No relevant side effects were seen in patients with significant fluid absorption. No mortality and no severe clinical morbidity was seen after the introduction of the new monitoring. CONCLUSION Using an irrigating fluid marked with 0.5% ethanol resulted in a decreased prevalence of fluid absorption over time.
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Guelrud M, Herrera I. Acetic acid improves identification of remnant islands of Barrett's epithelium after endoscopic therapy. Gastrointest Endosc 1998; 47:512-5. [PMID: 9647377 DOI: 10.1016/s0016-5107(98)70253-6] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
BACKGROUND Instillation of acetic acid onto the uterine cervix at colposcopy has been used for many years to highlight dysplastic areas and thereby enhance the ability to obtain targeted biopsy specimens. As part of an ongoing trial of multipolar electrocoagulation for Barrett's esophagus, we sought to develop a simple technique to identify small islands of residual specialized columnar epithelium after treatment. METHODS In 21 consecutive patients, 5 to 10 mL of 1.5% acetic acid was sprayed onto the distal esophagus using a spray catheter, followed immediately by spraying 50 mL of tap water. RESULTS Initially, a whitish coloration developed in both esophageal and gastric epithelia. After 2 to 3 minutes, the esophageal squamous mucosa remained white but the columnar epithelium became reddish. Remnant islands of Barrett's epithelium were outlined by a white rim. CONCLUSION Acetic acid instillation enhances the ability to detect small or indistinguishable remnant islands of columnar epithelium after endoscopic treatment of Barrett's esophagus. This method is safe, rapid, and inexpensive.
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Rost M, Karge E, Klinger W. Luminol and lucigenin amplified chemiluminescence and lipidperoxidation with brain microsomes from rats during ontogenetic development. EXPERIMENTAL AND TOXICOLOGIC PATHOLOGY : OFFICIAL JOURNAL OF THE GESELLSCHAFT FUR TOXIKOLOGISCHE PATHOLOGIE 1998; 50:253-5. [PMID: 9681657 DOI: 10.1016/s0940-2993(98)80093-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The chemiluminescence (CL) amplifiers luminol (LM) and lucigenin (LC) react with different reactive oxygen species (ROS) in dependence on the ROS generating system used. With liver microsomes LMCL indicates predominantly superoxide anion radicals, whereas LCCL is mainly a measure for hydroxyl radical formation or of reactive organic radicals. With brain microsomes only LCCL, but not LMCL could be measured. For both brain microsomes from newborn (both sexes) and 60 day-old (male) rats LCCL is dependent on protein and NADPH concentration, activity in newborns being only 15% compared with young adult rats. As compared with liver microsomes 10-fold higher protein concentrations are needed to obtain comparable LCCL, whereas the NADPH demand is the same as with liver. A distinct ontogenetic development was demonstrated: low activities in the fetus, in newborn and 10-day-old rat are followed by higher activities with increasing age, after a maximum at an age of 60 days a decline was observed. Microsomal lipidperoxidation (LPO) was measured as formation of thiobarbituric acid reactive substances (TBARS) and was also dependent on protein and NADPH concentration. Unexpectedly, LPO with brain microsomes from newborn rats did not show any developmental variation.
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Schoemaker RC, Burggraaf J, Cohen AF. Assessment of hepatic blood flow using continuous infusion of high clearance drugs. Br J Clin Pharmacol 1998; 45:463-9. [PMID: 9643619 PMCID: PMC1873547 DOI: 10.1046/j.1365-2125.1998.00711.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AIMS To provide methods for the translation of the concentration-time profile of highly cleared marker compounds into the underlying clearance and hepatic blood flow profile. METHODS Continuous infusion of indocyanine green or sorbitol was used to assess the effect of the hepatic blood flow modifiers exercise, somatostatin and octreotide. Three distinct methods are described for the translation of concentration into flow: 1. assuming successive phases of constant clearance 2. point to point estimation of clearance using estimates of concentration change 3. using a parametric description of the flow profile in combination with the differential equations describing the change in marker concentrations. RESULTS The marker compound concentration profiles are adequately described using the different methods. Exercise results in a decrease in hepatic blood flow of about 80%. Somatostatin and octreotide elicit an indistinguishable hepatic blood flow decrease from 1.49 to 1.07 l min(-1). Return to baseline takes much longer for octreotide (half-life 126+/-104 min) than for somatostatin (half-life 4.29+/-3.55 min). CONCLUSIONS Translation of concentration profiles into clearance profiles is possible making continuous assessment of hepatic blood flow feasible.
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Matsubara S, Fushimi K, Ogawa K, Kikkawa H, Nakata A, Kameda R, Kikuchi M, Naito K, Ikezawa K. Inhibition of pulmonary eosinophilia does not necessarily prevent the airway hyperresponsiveness induced by Sephadex beads. Int Arch Allergy Immunol 1998; 116:67-75. [PMID: 9623512 DOI: 10.1159/000023927] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The Lewis rat among highly inbred strains exhibits significant airway hyperresponsiveness (AHR) following intravenous administration of Sephadex G-200 (Sephadex). The aim of this study was to investigate the association of Sephadex-induced AHR with changes in airway inflammation in Lewis rats. METHODS A suspension (0.5 mg/ml/rat) of Sephadex was intravenously administered to male Lewis rats on days 0, 2 and 5. Measurement of airway responsiveness to serotonin, bronchoalveolar lavage (BAL) and histological study were performed on day 2-11. RESULTS Significant AHR induced by Sephadex was recognized on day2 (p < 0.05), and AHR reached a maximum on day 7 (p < 0.001). In the BAL study, eosinophils increased on day2 (p < 0.01) with a peak on day 5 (p < 0.05). In the histological study, we found Sephadex beads trapped in small arteries of the lung and granulomatous arteritis on day 2 or later. Pulmonary granulomas, horseshoe-shaped multinuclear giant cells, eosinophils and goblet cell hyperplasia were observed on day 2, and the degree became intense on day 5-7. GCC-AP0341 (10 mg/kg, i.p. x 3) inhibited the recruitment of eosinophils in BAL fluid and in lung tissue, but it did not inhibit AHR. The compound also inhibited pulmonary granulomas and goblet cell hyperplasia. CONCLUSION The mechanism of Sephadex-induced AHR may not be directly associated with inflammatory changes such as recruitment of eosinophils, pulmonary granulomas and hyperplasia of goblet cells in rats.
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Pataki A, Müller K, Green JR, Ma YF, Li QN, Jee WS. Effects of short-term treatment with the bisphosphonates zoledronate and pamidronate on rat bone: a comparative histomorphometric study on the cancellous bone formed before, during, and after treatment. Anat Rec (Hoboken) 1997; 249:458-68. [PMID: 9415453 DOI: 10.1002/(sici)1097-0185(199712)249:4<458::aid-ar5>3.0.co;2-n] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
To study the anti-resorptive effects of zoledronate and pamidronate on growing long bones we have performed a histomorphometric analysis of the three regions of the proximal tibial cancellous bone of bone formed before, during, and after drug treatment. Male rats (190-220 g) were treated subcutaneously for 10 days with zoledronate (0.028-2.8 microg/kg) or pamidronate (3.7-370 microg/kg) and sacrificed 5 days later. To delineate the three regions of cancellous bone, and for dynamic bone histomorphometry, calcein and demeclocycline were injected at various times. Both bisphosphonates caused a dose-dependent suppression of cancellous bone turnover and resorption to produce an increase in cancellous bone, but zoledronate was 100 times more potent than pamidronate. The increase in the bone amount and connectivity was more pronounced in the bone formed during treatment where transient bone resorption and normal bone formation led to a positive bone balance. In the bone formed before treatment, inhibition of bone resorption associated with reduced bone formation produced a net gain in amount of bone. Although both bone regions showed a positive bone balance, more bone accumulated in the bone formed during treatment probably because its trabecular bone surface was three times greater. In the primary spongiosa formed after treatment, a moderate increase in the bone amount and connectivity was observed only at the highest dose of both bisphosphonates. The bone formed before, during, and after treatment with bisphosphonates responds differently due to differences in bone architecture, rates of modeling and remodeling, and period of drug exposure.
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Grooteman MP, Nubé MJ, Daha MR, Van Limbeek J, van Deuren M, Schoorl M, Bet PM, Van Houte AJ. Cytokine profiles during clinical high-flux dialysis: no evidence for cytokine generation by circulating monocytes. J Am Soc Nephrol 1997; 8:1745-54. [PMID: 9355078 DOI: 10.1681/asn.v8111745] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Secretion of cytokines by monocytes has been implicated in the pathogenesis of dialysis-related morbidity. Cytokine generation is presumed to take place in two steps: induction of mRNA transcription for cytokines by C5a and direct membrane contact, followed by lipopolysaccharide (LPS)-induced translation of mRNA (priming/second signal theory, Kidney Int 37: 85-93, 1990). However, the in vitro conditions on which this theory was based differed markedly from clinical dialysis. To test this postulate for routine hemodialysis, 13 patients were studied cross-over with high-flux cuprammonium (CU), cellulose triacetate (CTA), and polysulfon dialyzers, using standard bicarbonate dialysate, as well as CTA with filtered dialysate (fCTA). Besides leukocytes, C3a, C5a, and limulus amebocyte lysate reactivity, tumor necrosis factor (TNF)-alpha, interleukin (IL)-1 beta, IL-6, IL-1RA, soluble TNF receptors, and IL-1 beta mRNA were assessed. Only during dialysis with CU did C5a increase significantly (561 to 8185 ng/ml, P < 0.001). Endotoxin content of standard bicarbonate was higher than filtered dialysate (median, 24.3 and < 5 pg/ml respectively, P = 0.002), whereas limulus amebocyte lysate reactivity was not detected in the blood, except in the case of CU. TNF-alpha levels were elevated before, and remained stable during, dialysis, independent of the modality used. IL-1 beta, IL-6, and mRNA coding for IL-1 beta could not be demonstrated. IL-1RA and soluble TNF receptors (p55/p75) were markedly elevated compared with normal control subjects, but showed no differences between fCTA and CTA. To summarize, no evidence was found for production and release of cytokines by monocytes during clinical high-flux bicarbonate hemodialysis, neither with complement-activating membranes nor with unfiltered dialysate. Therefore, this study sheds some doubt on the relevance of the "priming/second signal" theory for clinical practice. The data presented suggest that reluctance to prescribe the use of high-flux dialyzers, as advocated in many reports, may not be warranted.
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Jonsson M, Karlsson R, Evander M, Gustavsson A, Rylander E, Wadell G. Acetowhitening of the cervix and vulva as a predictor of subclinical human papillomavirus infection: sensitivity and specificity in a population-based study. Obstet Gynecol 1997; 90:744-7. [PMID: 9351757 DOI: 10.1016/s0029-7844(97)00418-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVE To evaluate acetowhite changes of the cervix and vulva as a predictor of human papillomavirus (HPV) infection. METHODS In this population-based study all women aged 19, 21, 23, and 25 years and registered as living in a primary health care area within the city of Umeå, Sweden were eligible for inclusion. Each participant underwent a gynecologic examination with sampling of epithelial cells for HPV-DNA detection and Papanicolaou smear. Colposcopy was performed 5 minutes after application of 5% acetic acid. A two-step polymerase chain reaction (PCR) technique was employed for HPV-DNA detection. RESULTS Colposcopy and sampling of epithelial cells could be performed in 535 women. The sensitivity of detection of HPV infection by the acetowhitening of the cervix was 22% (95% confidence interval [CI] 18%, 26%). The specificity of detection of HPV infection by the acetowhitening of the cervix was 90% (95% CI 87%, 93%). The sensitivity of detection of HPV infection by cytology was 13% (95% CI 10%, 16%), and the specificity was 99% (95% CI 98%, 100%). The combination of acetowhitening and cytology did not improve the diagnostic value. CONCLUSION Acetowhitening of the cervix and vulva has low sensitivity as a predictor of HPV infections as determined by PCR.
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Matsuno M, Shiota G, Umeki K, Kawasaki H, Kojo H, Miura K. Induction of plasma hepatocyte growth factor in acute colitis of mice. Inflamm Res 1997; 46:166-7. [PMID: 9197986 DOI: 10.1007/s000110050161] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
OBJECTIVE AND DESIGN The study examined plasma levels of hepatocyte growth factor (HGF) in acute colitis models on mice. MATERIALS Acute colitis was induced in male FVB mice (about 25 g) by intrarectal administration of 200 microliters of 0.5% acetic acid. METHODS Plasma was taken at 0, 12, 24, 36, 48 and 72 h after acetic acid treatment. Plasma HGF was measured by an enzyme immunoassay in duplicate. RESULTS Plasma levels of HGF at 0, 12, 24, 36, 48 and 72 h after acetic acid administration were 0.31 +/- 0.11 ng/ml (n = 4), 0.45 +/- 0.04 ng/ml (n = 4), 0.46 +/- 0.13 ng/ml (n = 4), 0.71 +/- 0.22 ng/ml (n = 4), 0.82 +/- 0.15 ng/ml (n = 4) and 0.44 +/- 0.04 ng/ml (n = 4), respectively. Significant increases in plasma HGF levels were observed at 36 and 48 h after the treatment (p < 0.05, compared to at 0 h). CONCLUSIONS Plasma HGF was induced by acute inflammation of colonic tissues. These findings suggest that HGF in blood may be one of the non-specific markers of inflammation in mice.
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