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PubMed1996

Quantitation of tobramycin concentration by laser microscopy in an epithelial cell of renal tubule.

To estimate tobramycin concentration in an epithelial cell of renal tubule without pulverizing or extracting it, we used immunohistochemical straining, using antibody coated colloidal gold. The intensity of reflection of colloidal gold at 514nm was measured with a laser microscope. Colloidal gold, reacted with tobramycin, was determined as having a gray scale on the microscopic image. This method was useful and sensitive enough to know the local concentrations of drug and/or other chemical substances.

Animals↗
PubMed1996

Cleavage of human corneal type VI collagen alpha 3 chain by matrix metalloproteinase-2.

The human cornea contains significant amounts of type VI collagen and matrix metalloproteinase-2 (MMP-2), but there has been no established relation between these two components. The objective of this study was to determine whether corneal type VI collagen was susceptible to digestion by MMP-2. Human corneas were frozen and then pulverized in liquid nitrogen. The type VI collagen was isolated by sequential extractions with sodium chloride buffer, guanidinium chloride solution, and guanidinium chloride/dithiothreitol solution. Visualization of type VI collagen alpha 3(VI) chain was made by using Western blots with specific monoclonal antibodies. The extracts were incubated up to 24 h with isolated, activated MMP-2. Within 4 h of incubation, two lower molecular weight bands (approximately 190 and 170 kDa) appeared. These bands increased in intensity with time but were not further digested into smaller fragments. This cleavage activity was inhibited by ethylenediaminetetraacetic acid (EDTA). Because type VI collagen represents approximately 25% of the corneal dry weight, its degradation properties may be important for the integrity of the stroma in scarring episodes and corneal diseases, such as keratoconus.

Animals↗
PubMed1996

[Detection of nordiazepam in the hair of drug addicts].

Hair samples were obtained from 36 drug addicts deceased from fatal heroin overdose. Samples were decontaminated with dichloromethane and pulverized. 50 mg of powdered hair were incubated 2 h at 40 degrees C in a phosphate buffer pH 7.6 in presence of deuterated internal standards (Nordiazepam-d5 and Oxazepam-d5) and extracted by a mixture ether/chloroform (80:20, v/v) at pH 8.4. After evaporation of the solvent, the dry extract was derivatized by silylation (BSTFA + 1% TMCS) and analyzed by gas chromatography coupled to mass spectrometry, with a detector operating in negative chemical ionization mode. 13 samples tested positive for Nordiazepam with concentrations ranging from 0.25 to 18.87 ng/mg of hair (mean: 4.16 ng/mg) and 5 positives for its metabolite, Oxazepam, with concentrations ranging from 0.11 to 0.50 ng/mg of hair (mean : 0.28 ng/mg).

Gas Chromatography-Mass Spectrometry↗
PubMed1977

Human urinary bladder carcinoma cell line (T24) in long-term culture: chromosomal studies on a wild population and derived sublines.

Karyotype changes of human urinary bladder carcinoma T24 cell line were studied in the course of 5-year in vitro cultivation. It has been found that the modal number of chromosomes gradually shifted from hypotetraploidy to triploidy during long-term cultivation. The number of endoreduplications was decreasing simultaneously and minute chromosomes occurring in a number of 4--5 in early passages appeared only rarely in later passages. Using conventional Giemsa staining, persistent marker chromosomes were detected in the wild population as well as in the eight sublines derived from T24 cells by cloning. The marker chromosomes were: metacentrics, subtelocentrics, telocentrics and long acrocentrics. Occasionally, there were found dicentrics, double-minutes, breaks and pulverization. The most characteristic marker was the metacentric chromosome the length of which corresponded approximately to the arm length of the chromosome No. 1. The metacentric chromosome in a number of 1--3 was present in 100% of T24 cells of the wild population and derived sublines at all passage levels examined.

Cell Line↗
PubMed1996

[Extracorporeal shockwave lithotripsy (SWL) of common bile duct calculi without previous endoscopic papillotomy].

In 17 patients (8 men, 9 women; mean age 61.5 years) with problematic bile-duct stones (papilla endoscopically inaccessible, residual bile-duct stones after recent laparoscopic cholecystectomy or age below 25 years) the chances of successful treatment by ESWL without sphincterotomy were examined. In 15 patients with solitary stones measuring up to 14 mm "pulverization-ESWL" produced complete freedom from stones after spontaneous migration of fragments through the intact papilla. Only two patients with two ductal stones measuring up to 15 mm still had residual fragments in the bile duct after treatment. The ideal stone for ESWL without sphincterotomy is thus the solitary bile-duct stone measuring up to 14 mm. Before performing a high-risk sphincterotomy, before re-operation and in young patients one should therefore always examine whether ESWL without sphincterotomy is indicated.

Adolescent↗
PubMed1997

HPLC/MS determination of buprenorphine and norbuprenorphine in biological fluids and hair samples.

An original method, based upon HPLC (high performance liquid chromatography)/Ionspray-MS, has been developed for the identification of buprenorphine (BUP) and norbuprenorphine (norBUP) in biological fluids and hair samples. Biological fluids (2 mL) are extracted at pH 8.4 by CHCl3/2-propanol/n-heptane (25:10:65, v/v) after addition of deuterated BUP (BUP-d4, 10 ng). Hair samples (40 mg) are extracted in the same conditions after decontamination by CH2Cl2, mechanical pulverization, addition of BUP-d4 (1 ng), acidic incubation (1 mL 0.1 N HCl, 56 degrees C overnight), then neutralization by NaOH. Analytes are separated on a 4-microns NovaPak C18 (Waters) column (150 by 2.0 mm, ID) with a mobile phase of acetonitrile/2 mM NH4COOH buffer, pH 3.0 (80:20, v/v; flow rate 200 microL/min; post column split 1:3). Detection is done by a Perkin-Elmer Sciex API-100 mass analyzer equipped with an ISP interface (nebulizing and curtain gas:99.95-% N2; main settings: orifice + 50 V, electron multiplier + 2400 V). The mean retention times for BUP, BUP-d4, and norBUP are 5.84, 5.79, and 4.42 min, respectively. For all compounds, mass spectra exhibit a unique, protonated molecular ion [M + H]+ at m/z 414 (norBUP), 468 (BUP), and 472 (BUP-d4), without any significant fragmentation. The lower limits of detection are 0.10 and 0.05 ng/mL blood, and 4 and 2 pg/mg hair for BUP and norBUP, respectively. BUP and norBUP concentrations measured in hair from six addicts under substitutive therapy by BUP ranged from 4 to 140 pg/mg, and from nondetected to 67 pg/mg, respectively. The good performances of this method in terms of both sensitivity and specificity make it a convenient alternative to HPLC/coulometry and GC/MS for the separate analysis of BUP and norBUP in biological samples.

Adult↗
PubMedDate not supplied

High rate of p53 overexpression in head and neck carcinomas detected with a refined ELISA.

p53 mutations are amongst the most prevalent alterations in human cancer. Overexpression of p53 is usually caused by mutation and is observed in a high percentage of squamous cell carcinomas of the head and neck (SCCHN). Fifty two fresh samples of SCCHN were examined for p53 overexpression and 23 tumor-free tonsils served as controls. Using the monoclonal antibody Pab 1801 a refined ELISA technique was employed. In contrast to established ELISA procedures tumor tissue was pulverized at -80 degrees C prior to the actual ELISA (ELISA I). Comparative p53 detection was carried out by immunohistochemistry (IHC) and a commercially available ELISA kit (ELISA II). The modified ELISA I revealed p53 overexpression in 48 tumor samples (92%). p53 detection was obtained in 26 cases (50%) with ELISA II and with IHC 39 stained positive for p53 (75%). All of the controls were negative for p53 with ELISA and IHC. The p53 staining in IHC showed a significant correlation with the grading of the tumor. The ELISA results of the p53 overexpression did not show any correlation with tumor size or stage and rate of metastasis or other clinical parameters. This ELISA represents a more sensitive detection method of p53 than any other technique so far. It improves on former ELISA and IHC results on p53 overexpression in squamous cell carcinoma of the head and neck and underlines the involvement and the importance of the p53 tumor suppressor protein in carcinogenesis of head and neck cancer.

Adult↗
PubMed1997

Enantioselective separation of methadone and its main metabolite in human hair by liquid chromatography/ion spray-mass spectrometry.

Optical isomers exhibit significant differences in their affinities for receptor sites, biotransformation and binding to serum and tissue proteins. Methadone has been used for the substitution of heroin addicts since 1964. The racemic form is used, i.e., a mixture of the biologically active R-form and the practically inactive S-form. To investigate methadone distribution, a chiral separation of the isomers was developed in human hair samples. The method involves decontamination of hair with water and acetone, pulverization in a ball mill, enzymatic hydrolysis in presence of deuterated internal standards, solid-phase extraction, and liquid chromatography/ion spray-mass spectrometry. Enantioselective separation of methadone and its main metabolite, EDDP, was obtained using an alpha1-acid glycoprotein column (100 by 4 mm ID). In all nine specimens obtained from subjects under racemic methadone treatment in a detoxification center, R- and S-enantiomers of methadone and EDDP were identified with the following concentrations: 2.58-10.22, 1.89-9.53, 0.42-1.73, and 0.40-2.10 ng/mg for R-methadone, S-methadone, R-EDDP, and S-EDDP, respectively. Results are suggestive of a predominance of the Renantiomer of methadone in human hair.

Chromatography, Liquid↗
PubMed1997

[Postpartum cerebral angiopathy of iatrogenic origin].

A 30 year old women, beginning her 19th day postpartum, was admitted for lowering of alertness. The day before she complained of cephalalagia. Neurologic examination showed pyramidal tract signs on the right part of the body, a bilateral Babinski sign, and central oculomotor palsy. She started a treatment by nasal pulverization of phenylephrine, a sympathomimetic vasoconstrictor, one week before, and took bromocriptine (5 mg per day) from childbirth to second week postpartum. CT scan was normal. Lumbar puncture showed a high level of proteins, from transsudative origin. Cerebral angiography showed a beading aspect of arterial branches, especially in the left middle cerebral artery territory. Two days after drug withdrawal, the patient recovered. This angiographic pattern has already been described in cases of cerebral angiopathy due to sympathomimetic drug abuse, and in cases of postpartum cerebral angiopathy. The chronology, in our case, makes the responsibility of the phenylephrine very likely. Nonetheless, ergot derivatives (i.e. ergonovine, bromocriptine) have also been accused of giving cerebral postpartum angiopathy. In our case, we think that bromocriptine may have triggered the cerebral angiopathy due to phenylephrine.

Bromocriptine↗
PubMed1997

Vaginal misoprostol for term labor induction.

Misoprostol is an effective agent for cervical ripening and induction of labor. The use of oxytocin was significantly decreased in patients treated with misoprostol versus dinoprostone. It has been used to induce over 1000 women in reported studies and has demonstrated a safety profile comparable with that of endocervical and vaginal dinoprostone. Uterine hyperstimulation was a concern in earlier trials, but at a reduced dose of 25 micrograms, the incidence has decreased to a level that is comparable with the values reported for dinoprostone. Misoprostol tablets are stable at room temperature and are considerably less expensive than the dinoprostone alternatives. Two additional factors pertaining to misoprostol administration must be taken into account before the drug is selected for vaginal use. First, Cytotec tablets are currently available in two strengths, 100 and 200 micrograms. This can lead to confusion or error if the clinician orders a quarter or half tablet. The order should always identify the strength in micrograms (25 or 50 micrograms). Second, the 100-microgram tablet is not scored; therefore, the proper dose should be carefully prepared by a pharmacist using a pill cutter. Key members of the hospital staff must be trained about the proper use of misoprostol for labor induction before initiating therapy. One alternative to directly inserting the tablet is to pulverize it and mix with a gel such as hydroxyethylcellulose gel. However, such compounding introduces the same problems with stability and uniformity of dose as experienced with dinoprostone gels. Despite the success of misoprostol in clinical trials, it is not approved for this indication, and the manufacturer of Cytotec does not plan to pursue approval. Therefore, independent, large-scale studies are warranted to more accurately assess the efficacy and overall safety of using intravaginal alprostadil for cervical ripening and labor induction. Additional clinical experience should also help to determine the best regimen and method of administration. From the data currently available, it appears that either a 25- or 50-microgram dose (one-fourth or one-half of a 100-microgram tablet) inserted into the posterior vaginal fornix and repeated at 4-5-hour intervals if needed, is a clinically effective regimen, and is associated with the least amount of adverse effects and complications. As with all labor inductions, uterine contractions and fetal heart rate should be monitored carefully throughout the procedure.

Administration, Intravaginal↗
PubMed1997

Reinforcement of acrylic resins for provisional fixed restorations. Part I: Mechanical properties.

Acrylic resins are commonly used in many dental applications; especially in the fabrication of provisional fixed partial dentures. Among noticed technical drawbacks associated with this material are unsatisfactory mechanical properties. Moreover, if acrylic resins are exposed to moist environment, water sorption results in further mechanical deterioration. In order to improve the mechanical properties, aluminum, magnesium, and zirconium oxide powders and pulverized E-glass particles were separately admixed with pre-polymerized acrylic resin beads prior to mixing with monomer liquid. Particle loading ratios were 1, 2 and 3 vol.% with respect to pre-polymerized beads. Poly(methyl methacrylate), poly(ethyl methacrylate) and poly(isobutyl methacrylate) were used as resin matrices. Furthermore, a metal primer agent was employed in order to form a strong interphase between admixed particles and polymer matrix phase. Samples were subjected to three-point transverse bending tests at a crosshead speed of 10 mm/min. It was concluded that (1) addition of particles generally increases the water sorbed by the composite resins systems, (2) however, two vol.% admixtures in a PMMA resin matrix showed significant improvements in the mechanical properties (p < 0.05), (3) among the oxide particles, zirconia exhibited the greatest improvements in modulus of elasticity, transverse strength, toughness and hardness, and (4) mechanical properties (transverse strength, 0.2% offset yield strength and modulus of elasticity) were linearly correlated to hardness numbers.

Acrylic Resins↗
PubMed1976

[Late replicating human X-chromosome in the early S-period].

The early S-period in cultured human lymphocytes was studied using the premature chromosome condensation technique. In the lymphocytes, isolated from females but not from males, one uncondensed G1-chromosome was detected among "pulverized" chromosomes which remained unlabeled with H3-thymidine. This chromosome is regarded as an inactivated X-chromosome. The data obtained are in agreement with the phenomenon of the delayed onset of DNA replication in the inactivated X-chromosomes.

Cells, Cultured↗
PubMed1998

Retrograde ureteropyeloscopic treatment of 2 cm. or greater upper urinary tract and minor Staghorn calculi.

PURPOSE: Upper urinary tract calculi that are too large to treat with extracorporeal shock wave lithotripsy are most commonly cleared with percutaneous endoscopic techniques. In a select group of patients who were poor candidates for percutaneous nephrostolithotomy we used retrograde endoscopic lithotripsy, and define the safety and efficacy of this modality in treating large, noninfectious stone burdens (2 cm. or greater). MATERIALS AND METHODS: A total of 51 patients with 66 large (2 cm. or greater) upper urinary tract stones were chosen for retrograde ureteroscopic surgery. Many of these patients had co-morbid conditions that precluded or complicated standard percutaneous treatment. Lithotripsy was based on the application of small diameter fiberoptic ureteroscopes and the holmium laser lithotriptor. Specifically, the 200 micro. laser fiber was used when lower pole renal access was required. Successful therapy was defined as total fragmentation of a stone burden with creation of fine sand and 2 mm. or smaller debris. Second look endoscopy was commonly performed in select patients with large branched calculi or stone burdens in excess of 3 cm. to rule out and treat large residual fragments. RESULTS: Of 51 patients 48 were treated solely in a retrograde ureteroscopic manner and in 3 either failure of lower pole access or infectious material encountered on initial endoscopy led to conversion to more standard percutaneous techniques. In 34 of 45 renal (76%), and 20 of 21 ureteral (95%) complete ureteroscopic fragmentation of the respective stone burden was accomplished after a single session. Second look endoscopy defined significant residual fragments requiring additional endoscopic lithotripsy in 8 of 15 large renal (53%) and 1 of 3 complex ureteral stone burdens. Success, that is complete pulverization of the stone burden to fine dust and small 2 mm. fragments, increased to 41 of 45 renal (91%) and all 21 ureteral calculi after these second look procedures. One patient required a third session to treat completely an exceptionally large (6 cm.) renal stone burden composed of pure cystine, thus increasing the overall success rate for renal calculi to 93%. Six-month followup data were available for 25 patients with large calculi treated ureteroscopically, of whom 15 (60%) had completely clear imaging, 6 (24%) had small lower pole debris that was decreasing on serial imaging and 4 (16%) had new stone growth which was, in part, related either to uncorrectable metabolic disorders or chronic renal scarring and urinary stasis. There were no intraoperative complications. Three postoperative complications included pyelonephritis in 1 patient, prostatic bleeding in 1 on anticoagulant therapy and a cerebral vascular accident 24 hours after the procedure in 1 with severe vascular disease. CONCLUSIONS: Large and complex upper urinary tract calculi can be addressed safely and efficiently with retrograde endoscopic techniques.

Adolescent↗
PubMed1976

Biotyping and serotyping of Propionibacterium acnes strains isolated from different diagnostic materials.

Fifty strains of Propionibacterium acnes, five strains with the previous designation Corynebacterium parvum and three strains of Propionibacterium avidum were agglutinated by Bacto-Corynebacterium acnes 554 antiserum (Difco); it was not possible to isolate any strain reacting only with 605 antiserum. Only one strain of C. parvum reacted with both sera. 48 (88 per cent) out of 54 strains (P. acnes and C. parvum) belonged to Voss' group I and 25 (47 per cent) belonged to Pulverer's biotype A. Strains from different diagnostic materials differed only biochemically (species acnes and avidum). The relations between these two species are discussed.

Czechoslovakia↗
PubMed2002

The post-mortem pathology of HIV-1-infected African children.

A retrospective review of autopsy findings and medical records in 33 HIV-infected children living in a Kenyan orphanage is described. Their ages ranged from 1 month to 18 years and median age at death was 71 months (range 7-156). Respiratory disorders were probably the primary cause of death in 21 (64%), in 19 (90%) of whom pyogenic parenchymal lung disease was detected. A presumptive clinical diagnosis of pulmonary tuberculosis had been made in 14 (67%); these children also had a history of recurrent acute lower respiratory tract infections (more than four infections/year). At autopsy, however, only one case of tuberculosis was identified (disseminated disease). Pneumocystis carinii pneumonia was not identified. Primary bacterial meningitis was detected in 33%. The associated findings included disseminated Kaposi sarcoma in two children and cryptococcal meningitis in one child. It is concluded that pyogenic infections are common causes of morbidity and mortality in HIV-1-infected African children. Management should include prompt treatment and, if indicated, prophylaxis for recurrent bacterial infections, and early evaluation and treatment of pulmonary tuberculosis.

AIDS-Related Opportunistic Infections↗
PubMed1989

Combined effects of aspirin and noise in causing permanent hearing loss.

Several authors have investigated the interaction of noise and aspirin in hearing loss, with conflicting results. We studied the combined effects of noise and high doses of aspirin on hearing in rats. Thirty-eight Sprague-Dawley rats were divided into the following five groups: (1) controls; (2) aspirin only; (3) noise only; (4) 8-day per 200 mg of aspirin per noise; and (5) 12-day per 200 mg of aspirin per noise. Auditory brain-stem-evoked responses were measured in each animal prior to, 24 hours after, and 3 weeks after aspirin and noise exposure. The animals were killed and hair cells were counted in 200-micron segments and expressed graphically. Results showed significant differences in permanent threshold shift and hair cell loss between all noise-exposed animals and non-noise-exposed animals. There was also a significantly greater amount of hair cell loss in group 5 when compared with groups 3 or 4. The 12-day per 200 mg of aspirin per noise regimen (group 5) also proved to be fatal for 6 of 15 of these animals, and caused significant weight loss in the survivors. No weight loss or deaths were noted in any other group.

Animals↗
PubMed1992

Glyoxylic acid in the study of autonomic innervation in the gerbil cochlea.

The autonomic innervation of the inner ear has been investigated earlier, yet questions concerning the origin, function, extent, and distribution of sympathetic nerves in the cochlea still remain unanswered. This study investigates the extent and distribution of adrenergic nerves in the cochlea. Our procedure combines the glyoxylic acid method of catecholamine fluorophore identification with rapid dissection, decalcification, and whole-mount slide preparation techniques to topographically trace the adrenergic innervation of the cochlear infrastructure. We have demonstrated that perivascular adrenergic innervation extends beyond the immediate branches of the modiolar artery and reaches into radiating arterioles. These findings also suggest the possibility of segmental regulation of cochlear blood flow.

Adrenergic Fibers↗