Current bladder cancer tests: unnecessary or beneficial?

Bladder cancer is currently diagnosed using cystoscopy and cytology in patients with suspicious signs and symptoms. These same tests are used to monitor patients with a history of bladder cancer for recurrence. The recurrence rate for bladder cancer is high, thus necessitating long-term follow-up. Urine cytology requires an experienced cytopathologist and is costly. It has high specificity, but low sensitivity for low-grade bladder tumors. Recently many non-invasive bladder cancer tests, utilizing markers found in the urine, have been developed. The FDA has approved several of these for the use is bladder cancer diagnosis, and many others are undergoing development and investigation. An ideal bladder cancer test would be non-invasive, highly sensitive and specific, inexpensive, easy to perform, and yield highly reproducible results. Many of the tests reviewed meet some, but not all, of these criteria.

Epithelioid hemangiomas of bone: spontaneous clinical and radiographic remission

A case of pathologic multifocal epithelioid hemangioma which occurred in the perigestational period is reported. This is the only reported case in which an epithelioid hemangioma, without treatment, went into radiographic and clinical remission. This case may suggest an alternative treatment for epithelioid hemangioma. Rather than radiation therapy or amputation, close observation of this benign neoplasm may be indicated.

Fidelity in planar cell polarity signalling

The polarity of Drosophila wing hairs displays remarkable fidelity. Each of the approximately 30,000 wing epithelial cells constructs an actin-rich prehair that protrudes from its distal vertex and points distally. The distal location and orientation of the hairs is virtually error free, thus forming a nearly perfect parallel array. This process is controlled by the planar cell polarity signalling pathway. Here we show that interaction between two tiers of the planar cell polarity signalling mechanism results in the observed high fidelity. The first tier, mediated by the cadherin Fat, dictates global orientation by transducing a directional signal to individual cells. The second tier, orchestrated by the 7-pass transmembrane receptor Frizzled, aligns each cell's polarity with that of its neighbours through the action of an intercellular feedback loop, enabling polarity to propagate from cell to cell. We show that all cells need not respond correctly to the presumably subtle signal transmitted by Fat. Subsequent action of the Frizzled feedback loop is sufficient to align all the cells cooperatively. This economical system is therefore highly robust, and produces virtually error-free arrays.

Benign fibrous histiocytoma: a rare finding on bone scan staging for prostate adenocarcinoma

Benign fibrous histiocytoma is a rare bone tumor that usually presents with localized pain and/or a pathological fracture. We report on a patient with adenocarcinoma of the prostate who had a radionuclide bone scan for staging, which was suspicious for metastatic disease. Histologic examination of left eleventh rib revealed a Benign Fibrous Histiocytoma (BFH). To our knowledge, this is the first BFH found solely on bone scan.

Cytoplasmic and/or nuclear accumulation of the beta-catenin protein is a frequent event in human osteosarcoma

The molecular events that precede the development of osteosarcoma, the most common primary malignancy of bone, are unclear, and concurrent molecular and genetic alterations associated with its pathogenesis have yet to be identified. Recent studies suggest that activation of beta-catenin signaling may play an important role in human tumorigenesis. To investigate the potential role of beta-catenin deregulation in human osteosarcoma, we analyzed a panel of 47 osteosarcoma samples for beta-catenin accumulation using immunohistochemistry. Potential activating mutations were investigated by sequencing exon 3 of the beta-catenin gene in genomic DNA isolated from tumor samples. Our findings revealed cytoplasmic and/or nuclear accumulation of beta-catenin in 33 of 47 samples (70.2%); however, mutation analysis failed to detect any genetic alterations within exon 3, suggesting that other regulatory mechanisms may play an important role in activating beta-catenin signaling in osteosarcoma. In our survival analysis, beta-catenin deregulation conferred a hazard ratio of 1.05, indicating that beta-catenin accumulation does not appear to be of prognostic value for osteosarcoma patients. When analyzed against other clinicopathologic parameters, beta-catenin accumulation correlated only with younger age at presentation (26.4 vs. 39.8 years). Nevertheless, our results demonstrate that the deregulation of beta-catenin signaling is a common occurrence in osteosarcoma that is implicated in the pathogenesis of osteosarcoma.

Comparison of the faecal microflora of patients with ankylosing spondylitis and controls using molecular methods of analysis

OBJECTIVES

To determine whether differences within the complex intestinal microflora can be demonstrated between patients with ankylosing spondylitis (AS) and healthy individuals.

METHODS

The composition of the faecal microflora of 15 ankylosing spondylitis patients and 15 matched controls was determined using a variety of nucleic acid-based methods, including denaturing gradient gel electrophoresis (DGGE). Concentrations of serum antibodies reactive with intestinal bacteria were determined. T-cell proliferation responses to autologous intestinal bacteria were determined using a bioluminescent assay.

RESULTS

DGGE demonstrated a unique and stable bacterial community in the faeces of each individual. No specific differences in colonization profiles were discernible between patients and controls. Analysis of individual bacterial groups using nucleic acid-based methods showed no differences in faecal colonization with Klebsiella pneumoniae or Bacteroides vulgatus. A significantly higher proportion of faecal samples from AS patients were found to contain sulphate-reducing bacteria compared with samples from controls (P=0.0004). Three out of five patients showed elevated T-cell proliferation responses to Bacteroides species cultured from their own faeces. The concentrations of serum immunoglobulin A (IgA) and IgM antibodies reactive with klebsiella or bacteroides cells were lower in the patient group relative to the controls.

CONCLUSIONS

By using DGGE, we have demonstrated the complexity and individuality of the human intestinal microflora and shown that this is a confounding factor in determining the possible significance of individual organisms in the pathogenesis of spondyloarthritis. Nevertheless, we demonstrated a higher prevalence of sulphate-reducing bacteria in the faeces of patients with AS. These organisms have been implicated in the pathogenesis of inflammatory bowel disease. We also detected a possible loss of immunological tolerance to autologous Bacteroides isolates in patients with AS.

Nuclear receptor agonists as potential differentiation therapy agents for human osteosarcoma

PURPOSE

This study was designed to investigate whether nuclear receptor agonists can be used as potential differentiation therapy agents for human osteosarcoma.

EXPERIMENTAL DESIGN

Four osteosarcoma cell lines (143B, MNNG/HOS, MG-63, and TE-85) were treated with proliferator-activated receptor (PPAR)gamma agonists, troglitazone and ciglitazone, and a retinoid X receptor (RXR) ligand, 9-cis retinoic acid. The proliferation and induction of apoptosis in the treated cells were assessed, as was the induction of alkaline phosphatase, a differentiation marker of osteoblasts.

RESULTS

The expression of PPARgamma was readily detected in all tested osteosarcoma lines. On treatment with the PPARgamma and RXR ligands, all four osteosarcoma lines exhibited a significantly reduced proliferation rate and cell viability. Among the four lines, 143B and MNNG/HOS were shown to be more sensitive to ligand-induced apoptosis, as demonstrated by the Crystal Violet and Hoechst staining assays. Of the three tested ligands, troglitazone was shown to be the most effective in inducing cell death, followed by 9-cis retinoic acid. Moreover, a strong synergistic effect on the induction of cell death was observed when both troglitazone and 9-cis retinoic acid or ciglitazone and 9-cis retinoic acid were administered to osteosarcoma cells. Troglitazone was shown to effectively induce alkaline phosphatase activity, a well-characterized hallmark for osteoblastic differentiation.

CONCLUSIONS

Our findings suggest that PPARgamma and/or RXR ligands may be used as efficacious adjuvant therapeutic agents for primary osteosarcoma, as well as potential chemopreventive agents for preventing the recurrence and metastasis of osteosarcoma after the surgical removal of the primary tumors.

Regulation of Frizzled by fat-like cadherins during planar polarity signaling in the Drosophila compound eye

Planar polarity is evident in the coordinated orientation of ommatidia in the Drosophila eye. This process requires that the R3 photoreceptor precursor of each ommatidium have a higher level of Frizzled signaling than its neighboring R4 precursor. We show that two cadherin superfamily members, Fat and Dachsous, and the transmembrane/secreted protein Four-jointed play important roles in this process. Our data support a model in which the bias of Frizzled signaling between the R3/R4 precursors results from higher Fat function in the precursor cell closer to the equator, which becomes R3. We also provide evidence that positional information regulating Fat action is provided by graded expression of Dachsous across the eye and the action of Four-jointed, which is expressed in an opposing expression gradient and appears to modulate Dachsous function.

MASK, a large ankyrin repeat and KH domain-containing protein involved inDrosophilareceptor tyrosine kinase signaling

The receptor tyrosine kinases Sevenless (SEV) and the Epidermal growth factor receptor (EGFR) are required for the proper development of the Drosophila eye. The protein tyrosine phosphatase Corkscrew (CSW) is a common component of many RTK signaling pathways, and is required for signaling downstream of SEV and EGFR. In order to identify additional components of these signaling pathways, mutations that enhanced the phenotype of a dominant negative form of Corkscrew were isolated. This genetic screen identified the novel signaling molecule MASK, a large protein that contains two blocks of ankyrin repeats as well as a KH domain. MASK genetically interacts with known components of these RTK signaling pathways. In the developing eye imaginal disc, loss of MASK function generates phenotypes similar to those generated by loss of other components of the SEV and EGFR pathways. These phenotypes include compromised photoreceptor differentiation, cell survival and proliferation. Although MASK is localized predominantly in the cellular cytoplasm, it is not absolutely required for MAPK activation or nuclear translocation. Based on our results, we propose that MASK is a novel mediator of RTK signaling, and may act either downstream of MAPK or transduce signaling through a parallel branch of the RTK pathway.

Expression of peripherin in the brain of macaques (Macaca mulatta and Macaca fascicularis) occurs in astrocytes rather than neurones and is associated with encephalitis

Peripherin is a member of the type III intermediate filament family, expressed in neurones of the peripheral nervous system of many species and in a discrete subpopulation of neurones of the central nervous system (CNS) during early development in rodents. Previous studies on rats have shown that peripherin immunoreactivity increased significantly in cell bodies of spinal motor neurones following axonal injury. Our study examined the expression of peripherin in the cerebrum of normal macaques (Macaca mulatta and Macaca fascicularis) and those with encephalitis of viral (simian immunodeficiency virus and simian virus 40) or autoimmune (experimental allergic encephalomyelitis) aetiology. Immunohistochemistry, immunoelectronmicroscopy, immunofluorescence and confocal microscopy were performed on tissue sections using antibodies against cell-specific markers and peripherin. Peripherin-positive cells were absent in the cerebrum of normal macaques of all ages examined, whereas animals with encephalitis had peripherin-positive cells associated with inflammatory infiltrates. Further evaluation revealed that these peripherin-positive cells were not neurones, but were predominantly astrocytes expressing glial fibrillary acidic protein. Our study suggests that peripherin is not neurone-specific in the CNS of macaques; peripherin is expressed in astrocytes of animals with encephalitis.

The epidemiology of organophosphate poisoning in urban Zimbabwe from 1995 to 2000

The objective of this study was to examine current organophosphate usage in Zimbabwe. A cross-sectional descriptive study was done to determine the trends in admissions for organophosphate poisonings in an urban Zimbabwe hospital from 1995 to 2000. Variables such as sex, age, season, geographic area, and intent were examined. In 183,569 records, 599 cases of organophosphate poisoning were found. Organophosphate poisonings increased by 320% over the six years. The male and female admissions' rates were similar (48% vs 52%); 82% of the patients were less than 31 years old. Suicide was the predominant reason for poisoning (74%). Of admissions of children under the age of 10, 62% were due to accidental ingestion. Mortality from organophosphate poisonings was 8.3% over the six years. Organophosphate poisoning is increasing rapidly. In the background of this alarming trend is the physical, mental, and social state of a Zimbabwean society wrought with hardships.

Local progression after operative treatment of metastatic kidney cancer

The cases of 78 patients with osseous metastases from kidney cancer were reviewed to determine the rate of local progression after operative resection as compared with more traditional intralesional procedures. Group I consisted of 41 (53%) patients who were treated with intralesional procedures involving internal fixation with or without curettage or polymethylmethacrylate. Of the 41 patients, additional operations were recommended for 17 (41%) of the patients who had local osseous progression. Fourteen additional procedures including nine wide resections with reconstruction, three amputations, and two mass excisions were done. Group II consisted of 37 (47%) patients who were treated with marginal or wide resection with or without reconstruction. In this group, only one patient required additional operative intervention for local osseous progression. Median survival of patients in Group I was 20 months compared with 35 months for patients in Group IL This study shows that despite shorter average survival, patients who undergo intralesional surgery are at high risk of reoperation for local progression. Resectional surgery should be considered in patients with skeletal metastases from kidney cancer to lessen the risk of reoperation for local progression.

Giant bilateral renal angiomyolipomas associated with tuberous sclerosis

Renal angiomyolipomas in patients with tuberous sclerosis can be associated with significant morbidity, mostly related to complications from bleeding. We describe a patient with tuberous sclerosis and massive bilateral renal angiomyolipomas (total tumor burden 5500 g) who presented with acute right renal hemorrhage. She was treated with right renal artery embolization followed immediately by right nephrectomy and left partial nephrectomy. The patient had a creatinine nadir of 1.3 mg/dL postoperatively. We demonstrate that nephron-sparing surgery is feasible, even in the setting of very large angiomyolipomas, such as the one presented here, currently the largest such tumor by weight reported.

Initial review of Electronic Residency Application Service charts by orthopaedic residency faculty members. Does applicant gender matter?

BACKGROUND

Orthopaedic surgery is a male-dominated field. As of 1998, women accounted for 42% of medical school graduates, yet only 6.9% of the total number of orthopaedic residents were female. The purpose of our study was to determine whether the Electronic Residency Application Service charts of female candidates for orthopaedic residencies are ranked lower by faculty reviewers than are those of male candidates with similar qualifications.

METHODS

After we obtained permission from the applicants, the Electronic Residency Application Service applications submitted by ninety male and ten female candidates for admission to a university orthopaedic residency program for the 1998 National Residency Matching Program were randomly divided into ten groups, consisting of the charts of nine male candidates and one female candidate. Each chart from a female candidate was altered into a "male" version, in which all names and personal pronouns were changed but which was otherwise identical to the original female version. Therefore, each group of ten charts existed as a paired set: one containing the true female chart and one, the altered "male" chart. The paired sets acted as their own control. One hundred and twenty-one faculty reviewers from fourteen orthopaedic residency programs around the United States each reviewed either the "male" or the female version of one set, without knowledge of the goals of the study, and ranked the ten charts in the order in which they would like to have the candidates as residents in their own programs. Each version of the sets was reviewed by at least five separate reviewers. Reviewers at a given institution were randomized to review different sets, so that there was no overlap among them. The rankings of the female-"male" pairs were compared with use of a standard paired t test.

RESULTS

No significant difference was detected in the rankings of the female and "male" charts (p = 0.5). The mean difference in rankings was -0.33, with a 95% confidence interval ranging from -1.41 (favoring females) to 0.74 (favoring "males").

CONCLUSIONS

The low percentage of female residents is not due to bias against female applicants in the initial chart-review phase of the orthopaedic residency selection process. It is possible that bias is introduced in other stages of the selection process, such as the interview.

Pulmonary cryptosporidiosis in simian immunodeficiency virus-infected rhesus macaques

Cryptosporidiosis is a common opportunistic infection in the gastrointestinal tract of human and nonhuman primates with AIDS. Pulmonary infection associated with Cryptosporidium spp. has not been previously reported in monkeys. Two macaques experimentally infected with simian immunodeficiency virus (SIV) had lesions containing cryptosporidial organisms involving the trachea, lungs, bile ducts, pancreas, and intestine. The pulmonary sections revealed moderate to severe bronchopneumonia associated with cryptosporidiosis. Numerous 2-4 microm oval Cryptosporidium spp. organisms were present in the cytoplasm of alveolar macrophages, multinucleated giant cells, and intestinal epithelial cells. Giant cells were positive for SIV by in situ hybridization. These are the first reported cases of cryptosporidiosis with involvement of pulmonary parenchyma in SIV-infected macaques.

Inotropes in the beta-blocker era

Beta-adrenergic blocking agents are now standard treatment for mild to moderate chronic heart failure (CHF). However, although many subjects improve on beta blockade, others do not, and some may even deteriorate. Even when subjects improve on beta blockade, they may subsequently decompensate and need acute treatment with a positive inotropic agent. In the presence of full beta blockade, a beta agonist such as dobutamine may have to be administered at very high (> 10 micrograms/kg/min) doses to increase cardiac output, and these doses may increase afterload. In contrast, phosphodiesterase inhibitors (PDEIs) such as milrinone or enoximone retain their full hemodynamic effects in the face of beta blockade. This is because the site of PDEI action is beyond the beta-adrenergic receptor, and because beta blockade reverses receptor pathway desensitization changes, which are detrimental to PDEI response. Moreover, when the combination of a PDEI and a beta-blocking agent is administered long term in CHF, their respective efficacies are additive and their adverse effects subtractive. The PDEI is administered first to increase the tolerability of beta-blocker initiation by counteracting the myocardial depressant effect of adrenergic withdrawal. With this combination, the signature effects of beta blockade (a substantial decrease in heart rate and an increase in left ventricular ejection fraction) are observed, the hemodynamic support conferred by the PDEI appears to be sustained, and clinical results are promising. However, large-scale placebo-controlled studies with PDEIs and beta blockers are needed to confirm these results.

Dilated cardiomyopathy associated with simian AIDS in nonhuman primates

BACKGROUND

Cardiomyopathy is being recognized with increasing frequency in patients with AIDS, yet the relationship between HIV infection and cardiac contractile dysfunction remains obscure. The purpose of the present study was to determine if infection with simian immunodeficiency virus (SIV) in nonhuman primates is associated with cardiac dysfunction and myocardial injury.

METHODS AND RESULTS

Left ventricular size and function were determined by 2D echocardiography in 16 rhesus macaques before and at weekly intervals following infection with cloned pathogenic SIV(mac) 239 or the highly attenuated SIV(mac) 239 nef deletion mutant. A second group of 15 rhesus macaques chronically infected with pathogenic (n=6) or nonpathogenic (n=9) virus were studied at >2 years following infection. Cardiac tissues from 24 rhesus macaques chronically infected (>2 years) with pathogenic SIV were reviewed for evidence of cardiac pathology. Acute infection (<6 weeks) with either pathogenic or nonpathogenic SIV caused neither contractile dysfunction nor cardiac pathology. However, LV ejection fraction was significantly (P<0.05) depressed (43+/-7%) in rhesus macaques chronically infected with pathogenic SIV compared with rhesus macaques chronically infected with nonpathogenic SIV (61+/-3%). Furthermore, two thirds of rhesus macaques that succumbed to simian AIDS had myocardial pathology including lymphocytic myocarditis (n=9) and coronary arteriopathy (n=6), with complete vessel occlusion (n=4) and associated myocardial infarction and necrosis.

CONCLUSIONS

This unique model is valuable in understanding the pathogenesis of cardiac injury associated with retroviral infection in a relevant nonhuman primate model of AIDS.

Recruitment of the protein tyrosine phosphatase CSW by DOS is an essential step during signaling by the sevenless receptor tyrosine kinase

The pleckstrin homology (PH) domain-containing protein Daughter of Sevenless (DOS) is an essential component of the Sevenless receptor tyrosine kinase (SEV) signaling cascade, which specifies R7 photoreceptor development in the Drosophila eye. Previous results have suggested that DOS becomes tyrosine phosphorylated during SEV signaling and collaborates with the protein tyrosine phosphatase CSW. We have investigated this possibility by identifying tyrosine residues 801 and 854 of DOS as the phosphorylated binding sites for the CSW SH2 domains. We show that these sites become phosphorylated in response to SEV activation and that phosphorylation of both sites is required to allow CSW to bind DOS. Mutant DOS proteins in which either Y801 or Y854 of DOS has been changed to phenylalanine are unable to function during signaling by SEV and other receptor tyrosine kinases. In contrast, we find that a mutant DOS protein in which all tyrosine phosphorylation sites except Y801 and Y854 have been removed is able effectively to provide DOS function during SEV signaling and to rescue the lethality associated with dos loss-of-function mutations. These results indicate that a primary role for DOS during signaling by SEV and other receptor tyrosine kinases is to become phosphorylated at Y801 and Y854 and then recruit CSW.

mirror controls planar polarity and equator formation through repression of fringe expression and through control of cell affinities

The Drosophila eye is divided into dorsal and ventral mirror image fields that are separated by a sharp boundary known as the equator. We have previously demonstrated that Mirror, a homeodomain-containing putative transcription factor with a dorsal-specific expression pattern in the eye, induces the formation of the equator at the boundary between mirror-expressing and non-expressing cells. Here, we provide evidence that suggests mirror regulates equator formation by two mechanisms. First, mirror defines the location of the equator by creating a boundary of fringe expression at the mid-point of the eye. We show that mirror creates this boundary by repressing fringe expression in the dorsal half of the eye. Significantly, a boundary of mirror expression cannot induce the formation of an equator unless a boundary of fringe expression is formed simultaneously. Second, mirror acts to sharpen the equator by reducing the mixing of dorsal and ventral cells at the equator. In support of this model, we show that clones of cells lacking mirror function tend not to mix with surrounding mirror-expressing cells. The tendency of mirror-expressing and non-expressing cells to avoid mixing with each other is not determined by their differences in fringe expression. Thus mirror acts to regulate equator formation by both physically separating the dorsal cells from ventral cells, and restricting the formation of a fng expression boundary to the border where the dorsal and ventral cells meet.

Aneurysmal bone cyst of the extremities. Factors related to local recurrence after curettage with a high-speed burr

BACKGROUND

Aneurysmal bone cyst is a benign, locally destructive lesion of bone. The rates of local recurrence after curettage have varied widely. Therefore, we performed a retrospective study of patients who had had an aneurysmal bone cyst in order to identify the rate of local recurrence and the prognostic factors related to local recurrence after use of contemporary methods of curettage with a high-speed burr.

METHODS

We reviewed the cases of forty patients who had been managed by the same surgeon for an aneurysmal bone cyst, as diagnosed on the basis of the latest pathological review, between January 1, 1976, and December 31, 1993. The patients were evaluated with regard to age, gender, the duration and type of symptoms, the presence or absence of pathological fracture, the status of the growth plate, the bone and part of the bone that were involved, the type of operative procedure, the outcome, the radiographic stage, the findings on magnetic resonance imaging and computerized tomography (when it became available) and on bone scintigraphy, and histological parameters. The median duration of follow-up was eighty-seven months (range, fifteen to 267 months). According to the criteria of Enneking, no patient had a stage-1 lesion (one with a surrounding rim of cortical bone), twenty-four had a stage-2 lesion (one with a clearly defined border but no cortical bone), and sixteen had a stage-3 lesion (one with no clearly defined border).

RESULTS

Of the forty patients, thirty-four had curettage with use of a high-speed burr. Of these thirty-four, twenty-two had filling of the defect with a cancellous autogenous graft; four, with a cancellous allograft; and three, with polymethylmethacrylate. In five patients, no material was put into the defect. The remaining six patients had resection through the margin of the lesion. Four (12 percent) of the thirty-four patients who had curettage had a local recurrence. No patient who had an excision through the margin of the lesion had a local recurrence. All local recurrences were in skeletally immature girls who were three, four, ten, and eleven years old. Univariate analysis with use of the chi-square, Fisher exact, and Wilcoxon log-rank tests showed that local recurrence was associated only with a young age (p = 0.0036) and open growth plates (p = 0.039). All local recurrences occurred within two years postoperatively, at two, seven, nine, and twenty-four months, and all were treated successfully with a second operation.

CONCLUSIONS

Rates of local control of almost 90 percent can be achieved with thorough curettage with use of a mechanical burr and without use of liquid nitrogen, phenol, or other adjuvants in patients who have an aneurysmal bone cyst of an extremity. A young age and open growth plates are associated with an increased risk of local recurrence.

Similar motor block effects with different disposition kinetics between lidocaine and (+ or -) articaine in patients undergoing axillary brachial plexus block during day case surgery

AIM

The aim of this investigation was to compare the clinical effects and pharmacokinetics of lidocaine and articaine in two groups of 15 patients undergoing axillary brachial plexus anesthesia.

METHOD

The study had a randomized design. Thirty patients were allocated to one of the two groups. Each patient received either lidocaine (600 mg = 2.561 mMol + 5 microg/ml adrenaline) or articaine (600 mg = 2.113 mMol + 5 microg/ml adrenaline), injected via the axilla of the brachial plexus over a period of 30 seconds. Onset of surgical analgesia was defined as the period from the end of the injection of the local anesthetic to the loss of pinprick sensation in the distribution of all three nerves.

RESULTS

The mean onset time of sensory block of the median nerve of both lidocaine and articaine were approximately 10 min. Lidocaine is biexponentially eliminated with a t1/2alpha of 9.95 +/- 14.3 min and a t1/2beta of 2.86 +/- 1.55 h. Lidocaine is metabolized into MEGX (mono-ethyl-glycyl-xilidide) (t(max) 2.31 +/- 0.84 h; C(max) 0.32 +/- 0.13 mg/l; t1/2beta 2.36 +/- 2.35 h). Lidocaine total body clearance was 67.9 +/- 28.9 l/h. Articaine is rapidly and monoexponentially eliminated with a t1/2beta of 0.95 +/- 0.39 h. The total body clearance of articaine is higher than that of lidocaine, 1,133 +/- 582 l/h vs 67.9 +/- 28.9 l/h, respectively (p < 0.0001). The volume of distribution (V(d)), of articaine is a factor 16 higher times than that of lidocaine (p < 0.0001).

CONCLUSION

For the axillary administration, lidocaine and articaine show similar pharmacodynamics with a different pharmacokinetic behavior and can therefore be used to the clinical preference for this regional anesthetic technique.