Characteristics of patients with severe root resorption.

Objectives: The purpose of this study was to compare a group of patients in whom all four maxillary incisors were resorbed at least 20% with a matched group.

Materials And Methods: Retrospective, case-control. Root resorption was measured on pre- and post-treatment periapical radiographs collected from 868 patients treated in private practices in southern California.

Unexpected observation of ion suppression in a liquid chromatography/atmospheric pressure chemical ionization mass spectrometric bioanalytical method.

Ion suppression is a well-known phenomenon in electrospray ionization (ESI) mass spectrometry. These suppression effects have been shown to adversely affect the accuracy and precision of quantitative bioanalytical methods using ion spray. Such suppression effects have not been as well defined in atmospheric pressure chemical ionization (APCI) and there is some debate whether these effects actually occur in the ionization process using APCI.

High-throughput non-heme iron assay for animal tissues.

Iron has been widely studied in nearly every realm of biology. However, current methodologies, such as genetic mapping or mutation screening, have been difficult to apply due to the lack of robust high-throughput methods for quantifying iron levels from cells or tissues. The measurement of total iron levels in tissues, usually done with atomic absorption spectroscopy, is impractical for large numbers of samples and includes the contribution of heme iron from hemoglobin contained in red blood cells.

Cyp1a1(-/-) male mice: protection against high-dose TCDD-induced lethality and wasting syndrome, and resistance to intrahepatocyte lipid accumulation and uroporphyria.

To study liver toxicity and uroporphyrin (URO) accumulation and urinary excretion, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a potent ligand for the aryl hydrocarbon receptor (AHR), is often used as the prototype. In this study, we asked the question how important is the role of CYP1A1 in causing TCDD toxicity. Using a single large intraperitoneal dose of TCDD (200 microg/kg) and following the response over an 8-week period, we found this dose: (a) was lethal in less than 4 weeks to Cyp1a1(+/+) males but not to Cyp1a1(-/-) males or to females of either genotype; (b) caused a wasting syndrome in Cyp1a1(+/+) but not Cyp1a1(-/-) mice; (c) resulted in thymic atrophy, regardless of gender or genotype; (d) decreased spleen size and caused leukocytopenia in males but not females of either genotype; (e) caused hepatocyte hypertrophy in Cyp1a1(+/+) more so than in Cyp1a1(-/-) mice; (f) increased intrahepatocyte lipids and total liver fat content in Cyp1a1(+/+) more than Cyp1a1(-/-) males and females; and (g) caused uroporphyria in Cyp1a1(+/+) males much more than Cyp1a1(+/+) females, or in Cyp1a1(-/-) mice.

Idiopathic arterial calcification in childhood.

Idiopathic arterial calcification in infancy is usually fatal with death in early life and diagnosis at post mortem. This report describes a unique, late presentation with hypertension and cardiac failure in a child aged 33 months, found to have widespread arterial calcification at radiological imaging. The calcium-phosphate axis was normal and there was no other demonstrable cause for calcification.

Economic evaluation of Helicobacter pylori eradication in the CADET-Hp randomized controlled trial of H. pylori-positive primary care patients with uninvestigated dyspepsia.

Background: Adult Helicobacter pylori-positive patients by 13C-urea breath test with uninvestigated dyspepsia symptoms were randomized to 1-week eradication treatment with omeprazole, metronidazole and clarithromycin (OMC) vs. omeprazole and placebo antimicrobials (OPP) in the Canadian Adult Dyspepsia Empiric Treatment-H. pylori-positive (CADET-Hp) study.

Development of an isokinetic functional electrical stimulation cycle ergometer.

An isokinetic functional electrical stimulation leg cycle ergometer (iFES-LCE) was developed for individuals with spinal cord injury (SCI). The iFES-LCE was designed to allow cycle training over a broad range of pedalling cadences (5-60 rev/min) to promote both muscular strength and cardiorespiratory fitness. A commercially available motorized cycle ergometer was integrated with a custom built FES system, a laptop computer, and a specialized chair that restricted lateral leg movements.

Effect of load during electrical stimulation training in spinal cord injury.

Electrical stimulation training is known to alter skeletal muscle characteristics after a spinal cord injury, but the effect of load on optimizing the training protocol has not been fully investigated. This study investigated two electrical-stimulation training regimes with different loads on intramuscular parameters of the paralyzed lower limbs. Six paraplegic individuals with a spinal cord injury underwent electrical stimulation training (45 min daily for 3 days per week for 10 weeks).

Inhibitory potency of twice-a-day omeprazole on gastric acidity is enhanced by eradication of H. pylori in duodenal ulcer patients.

The gastric pH-elevating effect of proton pump inhibitors such as omeprazole has been reported to be greater in the presence than in the absence of an H. pylori infection. It is unknown if this effect persists when a higher dose of omeprazole is taken.

A mechanism of oxygen sensing in yeast. Multiple oxygen-responsive steps in the heme biosynthetic pathway affect Hap1 activity.

Heme plays central roles in oxygen sensing and utilization in many living organisms. In yeast, heme mediates the effect of oxygen on the expression of many genes involved in using or detoxifying oxygen. However, a direct link between intracellular heme level and oxygen concentration has not been vigorously established.

The prevalence of clinically significant endoscopic findings in primary care patients with uninvestigated dyspepsia: the Canadian Adult Dyspepsia Empiric Treatment - Prompt Endoscopy (CADET-PE) study.

Background: Uninvestigated dyspepsia is common in family practice. The prevalence of clinically significant upper gastrointestinal findings (CSFs) in adult uninvestigated dyspepsia patients, and their predictability based on history, is unknown.

Methods: Prompt endoscopy was performed within 10 days of referral, in 1040 adult patients presenting with uninvestigated dyspepsia at 49 Canadian family practitioner centres.

Angiographic features of 26 children with Takayasu's arteritis.

Background: Takayasu's arteritis (TA) is a chronic idiopathic inflammatory disease affecting primarily the aorta, its proximal branches and the pulmonary arteries.

Objectives: To retrospectively review the angiograms of children with TA so as to describe the patterns of vascular involvement.

Patients And Methods: Twenty-six children with TA who differed from most other studies in that almost all of them presented with hypertension, reflecting the incidence of abdominal aortic and renal artery involvement.

A comparison of the quantitative methods for the analysis of the platinum-containing anticancer drug [cis-[amminedichloro(2-methylpyridine)]platinum(II)] (ZD0473) by HPLC coupled to either a triple quadrupole mass spectrometer or an inductively coupled plasma mass spectrometer.

The use of high performance liquid chromatography coupled with inductively coupled plasma mass spectrometry (HPLC-ICPMS) as means for the quantitative determination of ZD0473, a platinum anticancer drug, and its related biologically active "aqua" compounds in biofluid samples is described. The performance of the resulting HPLC-ICPMS method was compared with that of a conventional HPLC-triple quadrupole mass spectrometer-based (HPLC-MS/MS) system for properties such as limit of detection, linearity, and reproducibility using spiked samples. The methods were then applied to the determination of plasma ultrafitrate concentrations of ZD0473 in dog plasma samples obtained following intravenous and oral administration at 0.

Benzamide derivatives as blockers of Kv1.3 ion channel.

The voltage-gated potassium channel, Kv1.3, is present in human T-lymphocytes. Blockade of Kv1.

Acid inhibitory potency of twice a day omeprazole is not affected by eradication of Helicobacter pylori in healthy volunteers.

Background And Aims: The acid inhibitory effect of proton pump inhibitors is reported to be greater in the presence than in the absence of an H. pylori infection. This study was undertaken to test the hypothesis that the acid inhibitory effect of omeprazole given twice a day is greater in H.

Uroporphyrin accumulation in hepatoma cells expressing human or mouse CYP1A2: relation to the role of CYP1A2 in human porphyria cutanea tarda.

In experimental animals, CYP1A2 is absolutely required for the development of uroporphyria induced by treatment with polyhalogenated aromatic compounds or other compounds. Although the role of this CYP in clinical uroporphyria, porphyria cutanea tarda (PCT), is not clear, Cyp1a2(-/-) mice are resistant to the development of uroporphyria. Here, we compared the abilities of human and mouse CYP1A2 expressed in mouse hepatoma Hepa-1 cells to: (i) catalyze CYP1A2-dependent methoxyresorufin demethylase (MROD), and (ii) support uroporphyrin (URO) accumulation.

p38 Inhibitors: piperidine- and 4-aminopiperidine-substituted naphthyridinones, quinolinones, and dihydroquinazolinones.

We have synthesized a series of C7-piperidine- and 4-aminopiperidine-substituted naphthyridinones, quinolinones, and dihydroquinazolinones that are highly potent inhibitors of both p38MAP kinase activity and TNF-alpha release. The 4-aminopentamethylpiperidine naphthyridinone 5, which was designed to block metabolism at major 'hot spots', combined excellent inhibitory potency with good oral bioavailability in the rat.

Treating Helicobacter pylori infection in primary care patients with uninvestigated dyspepsia: the Canadian adult dyspepsia empiric treatment-Helicobacter pylori positive (CADET-Hp) randomised controlled trial.

Objective: To determine whether a "test for Helicobacter pylori and treat" strategy improves symptoms in patients with uninvestigated dyspepsia in primary care.

Design: Randomised placebo controlled trial.

Setting: 36 family practices in Canada.

Orthodontic graduate education survey, 1983-2000.

Throughout academic year 1999/2000, the fourth in a series of national surveys sponsored by the American Association of Orthodontists Council on Education was conducted to determine the status of graduate education, to assemble information on the didactic and clinical material being taught, and to provide a basis for comparison with past and future studies. The results of the previous studies were published in 1984, 1989, and 1995. The specific purpose of the 2000 study was to identify trends and evaluate new developments in orthodontic education over the past 17 years.

Vaginitis emphysematosa associated with an abnormal Pap smear.

Vaginitis emphysematosa is an uncommon inflammatory condition that is aetiologically linked to trichomonal or gardnerella infection, and has been associated with immunosuppressive disorders. The disease does not have deleterious sequelae and resolves on treating the underlying infection. We describe a case in which the disease predominantly affected the cervix leading to an abnormal pap smear and colposcopic investigation.

Transcription factor BACH2 is transcriptionally regulated by the BCR/ABL oncogene.

Expression of BCR/ABL, a constitutively active tyrosine kinase, is a primary event in the pathogenesis of chronic myeloid leukemia (CML) and Ph-positive acute lymphoblastic leukemia (Ph+ALL). Inhibition of the BCR/ABL kinase activity in the BV173 CML cell line with STI571 resulted in a significant overexpression of a 10-kb novel mRNA, found to be the human ortholog of the murine Bach2, a B-cell-specific transcription factor. The human BACH2 cDNA is >9,120 bp long and includes an open reading frame of 2,526 bp encoding a protein with a basic leucine zipper (bZip) and a BTB/POZ domain, mediating DNA-binding and heterodimerization.