Biomedical subjects

K Brandt

Publications and source records attributed to K Brandt.

At least 19 recordsLinked to original sources

PubMed2007

Superiority of the Lyon schuss view over the standing anteroposterior view for detecting joint space narrowing, especially in the lateral tibiofemoral compartment, in early knee osteoarthritis.

OBJECTIVE: To evaluate the validity of using the conventional anteroposterior (AP) radiograph of the knee in order to identify joint space narrowing (JSN) at an early stage of osteoarthritis (OA). METHODS: Grading of JSN using a 0-5 score and quantitative measurement of joint space width (JSW) of the medial and lateral compartments of the tibiofemoral joint in AP and fluoroscopically assisted posteroanterior Lyon schuss (LS) radiographs of 202 patients with knee OA. RESULTS: Knees without definite JSN (score <2) were twice as common in AP than in LS radiographs (36.1% vs 18.8%). The number of knees showing definite medial JSN was identical in both views but four knees showing a medial OA in AP view were classified differently in the LS radiographs (three bicompartmental OA and one lateral OA). The frequency of lateral JSN was approximately twice as great in the LS view as in the AP view. JSN score was significantly higher (p<0.001) and JSW was significantly smaller (p<0.01) in the LS view than in the AP view. In knees with definite JSN, JSW of the compartment with no narrowing was significantly (p<0.04) larger than in knees that did not exhibit definite JSN. Medial JSW and lateral JSW were inversely correlated (p<0.001). CONCLUSIONS: The standing AP radiograph performed poorly in identifying both the location of JSN in patients with early tibiofemoral OA (especially, lateral OA) and the severity of JSN. The LS radiographs are preferable to standing AP views for the selection of patients for therapeutic trials of structure-modifying OA drugs.

Aged↗

PubMed2006

Assessment of the radioanatomic positioning of the osteoarthritic knee in serial radiographs: comparison of three acquisition techniques.

OBJECTIVE: Recent studies using various standardized radiographic acquisition techniques have demonstrated the necessity of reproducible radioanatomic alignment of the knee to assure precise measurements of medial tibiofemoral joint space width (JSW). The objective of the present study was to characterize the longitudinal performance of several acquisition techniques with respect to long-term reproducibility of positioning of the knee, and the impact of changes in positioning on the rate and variability of joint space narrowing (JSN). METHODS: Eighty subjects were randomly selected from each of three cohorts followed in recent studies of the radiographic progression of knee osteoarthritis (OA): the Health ABC study (paired fixed-flexion [FF] radiographs taken at a 36-month interval); the Glucosamine Arthritis Intervention Trial (GAIT) (paired metatarsophalangeal [MTP] radiographs obtained at a 12-month interval), and a randomized clinical trial of doxycycline (fluoroscopically assisted semiflexed anteroposterior (AP) radiographs taken at a 16-month interval). Manual measurements were obtained from each radiograph to represent markers of radioanatomic positioning of the knee (alignment of the medial tibial plateau and X-ray beam, knee rotation, femorotibial angle) and to evaluate minimum JSW (mJSW) in the medial tibiofemoral compartment. The effects on the mean annualized rate of JSN and on the variability of that rate of highly reproduced vs variable positioning of the knee in serial radiographs were evaluated. RESULTS: Parallel or near-parallel alignment was achieved significantly more frequently with the fluoroscopically guided positioning used in the semiflexed AP protocol than with either the non-fluoroscopic FF or MTP protocol (68% vs 14% for both FF and MTP protocols when measured at the midpoint of the medial compartment; 75% vs 26% and 34% for the FF and MTP protocols, respectively, when measured at the site of mJSW; P<0.001 for each). Knee rotation was reproduced more frequently in semiflexed AP radiographs than in FF radiographs (66% vs 45%, P<0.01). In contrast, the FF technique yielded a greater proportion of paired radiographs in which the femorotibial angle was accurately reproduced than the semiflexed AP or MTP protocol (78% vs 59% and 56%, respectively, P<0.01 for each). Notably, only paired radiographs with parallel or near-parallel alignment exhibited a mean rate of JSN (+/-SD) in the OA knee that was more rapid and less variable than that measured in all knees (0.186+/-0.274 mm/year, standardized response to mean [SRM]=0.68 vs 0.128+/-0.291 mm/year, SRM=0.44). CONCLUSION: This study confirms the importance of parallel radioanatomic alignment of the anterior and posterior margins of the medial tibial plateau in detecting JSN in subjects with knee OA. The use of radiographic methods that assure parallel alignment during serial X-ray examinations will permit the design of more efficient studies of biomarkers of OA progression and of structure modification in knee OA.

Doxycycline↗

PubMed2005

The genome of the virulent phage Lc-Nu of probiotic Lactobacillus rhamnosus, and comparative genomics with Lactobacillus casei phages.

The complete 36,466-bp genome sequence of the virulent phage Lc-Nu of probiotic Lactobacillus rhamnosus was determined. The linear dsDNA with a GC-content of 44.2% contained 3' single-stranded cohesive ends of 12 nucleotides. A total of 51 putative open reading frames (orfs) were predicted. Lc-Nu showed to be evolutionary closely related to the temperate Lactobacillus casei phages phi AT3 and A2. High DNA homology with phi AT3 was shared over the late transcribed genes, and the highest homology with A2 was within the genetic switch region. The truncated cI-like repressor was the only lysogeny related gene left, which strongly suggested Lc-Nu to be recently evolved from a temperate origin. Three putative methylases and endonucleases were detected from the region of early-transcribed genes. The putative origin of replication within the putative gene orf34 homologous to replisome organizers resembled to that of lambdoid phages. The present study suggested Lc-Nu to be a new candidate for the proposed Sfi21-like species.

Base Composition↗

PubMed2003

Flavone C-glycoside, phenolic acid, and nitrogen contents in leaves of barley subject to organic fertilization treatments.

From the leaves of barley, Hordeum vulgare, one new flavone C-glucoside and three known flavone glucosides were isolated and characterized by (1)H and (13)C NMR and MALDI-TOF-MS. The novel flavone C-glucoside was isovitexin 7-O-beta-[6' "-O-(E)-p-coumaroyl]glucoside (6' "-coumaroylsaponarin), and the known compounds were isovitexin 7-O-beta-[6' "-O-(E)-feruloyl]glucoside, isoorientin 7-O-beta-[6' "-O-(E)-feruloyl]glucoside, and tricin 7-O-beta-glucoside. The sum of all the flavone glycosides and soluble phenolic acids in the leaves decreased with increased rate of plant nutrients given in animal manure and with increased crop yield. All of the major phenylpropanoids showed the same general response to nutrient level. The concentration of nitrogen in the leaves was not directly related to nutrient application or to contents of phenylpropanoids.

Fertilizers↗

PubMed2003

Intracranial epidermoid cyst in a horse.

An intracranial epidermoid cyst was diagnosed in a Haflinger gelding aged 12 years suffering from episodes of neurological disturbance, apathy and fever. The extracerebral cyst was located in the region of the tentorium cerebelli and measured 9 x 8 x 5 cm. It displaced the cerebral hemispheres anteriorly and compressed the cerebellum and brainstem underneath. Histologically, the cyst was lined by keratinizing, stratified squamous epithelium and contained keratin scales, debris, focal haemorrhages, and degenerating inflammatory cells. The epithelium was supported by a vascularized fibrous capsule that firmly adhered to the dura mater. Multifocal haemorrhages and moderate lymphohistiocytic infiltrations were present in the capsule. The basement membrane was disrupted focally, and single or clustered cytokeratin-positive epithelial cells were detected in the fibrous capsule, suggesting a possible transition to malignancy.

Animals↗

PubMed2002

TSST-1 induces Th1 or Th2 differentiation in naïve CD4+ T cells in a dose- and APC-dependent manner.

Superantigens are potent activators of the immune system, causing a variety of diseases, ranging from food poisoning to septic shock. Here, we examined the effects of different toxic shock syndrome toxin 1 (TSST-1) concentrations on the activation, proliferation and synthesis of interferon-gamma (IFN-gamma) and interleukin-4 (IL-4) in purified naïve human CD4+ T cells in a serum-free in vitro system. TSST-1 given in low doses (1-10 pg/ml) generates a pronounced T helper 2 (Th2)-like cytokine profile, characterized by elevated IL-4-expressing T-cell populations and reduced IFN-gamma-producing populations, whereas higher doses (100 pg/ml) induce a Th1-like profile, with increased expression of IFN-gamma and reduced expression of IL-4. These patterns were even more pronounced by adding exogenous cytokines like IL-12 and IL-4 and by the type of antigen-presenting cells (APCs). Thus, B cells induced Th2 shifts, whereas monocytes favoured Th1 induction. Moreover, IL-12 in conditions with B cells counteracted their Th2 bias. Interestingly, in purified naïve T-cell cultures, containing a small population of HLA-DR+ T cells, Th1/Th2 differentiation can be induced by TSST-1 too. There, Th-cell polarization is strongly dependent on TSST-1 concentration, indicating that this is a key parameter in regulating the differentiation of T cells. In conclusion, our data show that Th1/Th2 differentiation of TSST-1-stimulated naïve T cells is controlled by the type of APCs, and in APC-depleted cultures, it depends on the presence of HLA-DR+ cells and TSST-1 concentration.

Antigen Presentation↗

PubMed2001

Supramolecular assistance to regioselectivity in the reactions of chlorocyclophosphazenes with sodium oxyanions: macrocyclic effect and anion dependence.

Comparative studies of the naphtholysis of crown-bearing tetrachlorocyclotriphosphazene 2 and its acyclic analogue, nongem-diethoxytetrachlorocyclotriphosphazene 5 (which was synthesized and isolated in the pure cis form for the purpose of this study), reveal a significant macrocyclic effect of the substituent on both the kinetics and regiochemistry of chlorine substitution in the N(3)P(3) ring. Whereas substitution of 5 with sodium naphthoxide provided moderate yields of the respective sterically and electronically favored nongem-naphthoxydiethoxy derivative as the major product, isolated as the mixture of cis and trans isomers 8 + 9, the corresponding reaction of crown substrate 2 resulted in highly regioselective formation of the gem-to-macrocycle substituted mononaphthoxy PNP-crown derivative 11a. The importance of the PNP-crown related effects for the regio- and stereocontrol of the substitution of chlorine atoms in the N(3)P(3) ring is discussed in terms of supramolecular sodium cation-assisted interactions between the ring oxy substituent(s) and incoming oxyanions. To approach the problem of the anion-dependence of the regioselectivity, a comparison has been drawn between the reactions of the PNP-crown substrate 2 with sodium arylates derived from beta-naphthol (10a) and phenol (10b), carried out with equimolar or 100% excess sodium oxyanion with respect to 2, and the corresponding reactions of 2 with sodium monoenolates derived from the beta-dicarbonyl compounds: acetylacetone (10c) and ethyl acetylacetate (10d). The effectiveness of supramolecularly assisted transition state stabilization is found to be dependent not only on the dimensional complementarity between the cation and the macrocycle but also on the properties of the four interacting ionic centers according to the HSAB principle and on the nature of the electronic interaction of the PNP-crown substituent with the N(3)P(3) ring, the latter determining the extent of regiocontrol to either one or two macrocyclic chloride functions. The increase of the extent of regioselectivity of gem-substitution at the PNP-macrocycle when passing from arylate to beta-dicarbonyl enolate oxy anions is related to the observed trends in the (31)P NMR chemical shifts and refers to the electronic structure of the oxy substituent.

Journal Article↗

PubMed2001

Structure-property relationships of a tetrapyrrolidinyl PNP-lariat ether and its complexes with potassium, sodium, and silver cations.

Spectral properties of the tetrapyrrolidinyl PNP-lariat ether, L, and its complexes with K+, Na+, and Ag+ were investigated. Crystal structures of L and its complex with potassium iodide [KL]I were determined. Protonation constants of the ligand and formation constants of its complexes with Ag+, K+, and Na+ in aqueous solutions were determined. 1H NMR, 31P NMR, FTIR, and ESIMS spectra as well as potentiometric measurements indicate that complexation of Ag+ involves participation of the polyether oxygen donors and the endocyclic nitrogen atom of the cyclophosphazene ring. On the other hand, for complexation of K+ and Na+, only polyether oxygen atoms are involved. The latter conclusion is confirmed in the solid-state structure of the [KL]I complex.

Journal Article↗

PubMed2001

Characterization of the eugenol hydroxylase genes (ehyA/ehyB) from the new eugenol-degrading Pseudomonas sp. strain OPS1.

During the screening for bacteria capable of converting eugenol to vanillin, strain OPS1 was isolated, which was identified as a new Pseudomonas species by 16 s rDNA sequence analysis. When this bacterium was grown on eugenol, the intermediates, coniferyl alcohol, ferulic acid, vanillic acid, and protocatechuic acid, were identified in the culture supernatant. The genes encoding the eugenol hydroxylase (ehyA, ehyB), which catalyzes the first step of this biotransformation, were identified in a genomic library of Pseudomonas sp. strain OPS1 by complementation of the eugenol-negative mutant SK6165 of Pseudomonas sp. strain HR199. EhyA and EhyB exhibited 57% and 85% amino acid identity to the eugenol hydroxylase subunits of Pseudomonas sp. strain HR199 and up to 34% and 54% identity to the corresponding subunits of p-cresol methylhydroxylase from P. putida. Moreover, the amino-terminal sequences of the alpha- and beta-subunits reported recently for an eugenol dehydrogenase of P fluorescens E118 corresponded well with the appropriate regions of EhyA and EhyB. Downstream of ehyB, an open reading frame was identified, whose deduced amino acid sequence exhibited up to 71% identity to azurins, representing most probably the gene (azu) of the physiological electron acceptor of the eugenol hydroxylase. The eugenol hydroxylase genes were amplified by PCR, cloned, and functionally expressed in Escherichia coli.

Bacterial Proteins↗

PubMed2001

Phage-related DNA polymorphism in dairy and probiotic Lactobacillus.

Various DNA-based methods are presently being applied for identification of industrial bacterial cultures including dairy starter and probiotic strains of Lactobacillus. The success of strain-specific identification depends on the power of the DNA-based methods to reveal intraspecies DNA polymorphism. This study reveals that all eleven arbitrarily chosen Lactobacillus rhamnosus starter, laboratory and probiotic strains contain Lb. rhamnosus phage Lc-Nu related nucleotide sequences. One of these highly homologous regions in the genome of phage Lc-Nu was the 2.4kb HindIII fragment, which has been sequenced. Nucleotide sequence analysis suggested that one side of the 2.4kb HindIII fragment encodes a phage Lc-Nu helicase and accordingly represents an early gene region of phage Lc-Nu genome. Five forward and five reverse primers were derived from the nucleotide sequence of the 2.4kb HindIII fragment of phage Lc-Nu DNA for PCR-based identification of the eleven Lb. rhamnosus strains included in this study. Six different types of PCR product patterns were obtained. Among the patterns three were unique to particular Lb. rhamnosus strains. The results suggest that phage-related DNA sequences are, surprisingly, distributed widely among the Lb. rhamnosus strains, and that these sequences could also be a source of DNA polymorphism to apply for DNA-based identification of bacterial strains. Phage Lc-Nu related DNA homology was also found in the chromosome of Lb. casei, the species closely related to Lb. rhamnosus.

Bacteriophages↗

PubMed2001

Sciatic nerve reconstruction: limb preservation after sarcoma resection.

Limb salvage for extremity sarcoma has become the standard of care when possible. This review attempts to determine the outcome of sciatic nerve reconstruction after surgical tumor resection. The authors' objective was to determine the clinical value of extremity salvage with such a defect. Five patients (two male, three female) were selected from a department database at The University of Texas M.D. Anderson Cancer Center between 1995 and 1999 who met the following criteria: lower limb tumor resection involving a gap in the sciatic nerve with subsequent nerve autograft reconstruction. An additional patient who underwent primary sciatic nerve neurorrhaphy was also included. The average tumor size was 203 cm2. The most common tumor histology was spindle cell sarcoma. The average autograft length was 13 +/- 3.2 cm with one to four cables employed. Currently, 3 patients are still alive. Four of the 5 patients who received sciatic autonerve grafts reported partial distal sensory recovery subjectively. The patient who underwent primary neurorrhaphy has both motor and sensory innervation 42 months after surgery. Although not ideal for all patients, sciatic nerve reconstruction is a viable option for those willing to undergo limb preservation. Notable limitations to daily activity do not appear to be present, and patients are able to ambulate with or without assistive devices. With aggressive rehabilitation, some patients are able to function quite well with this bioprosthesis. Patients should consider, however, that their extremity is on loan. Substantial wound complications or infections may ultimately lead to amputation.

Adult↗

PubMed2001

Incidence of pressure ulcers in a neurologic intensive care unit.

OBJECTIVES: To determine the risk factors for pressure ulceration in an intensive care setting, to evaluate the Braden scale as a predictor of pressure ulcer risk in critically ill patients, and to determine whether pressure ulcers are likely to occur early in the hospital stay. DESIGN: Cohort study of patients with no preexisting ulcers with a 3-month enrollment period. SETTING: The neurologic intensive care unit and the neurologic intermediate unit at a primary care/referral hospital with a level I trauma center. PATIENTS: A total of 186 patients entered the study. INTERVENTION: Within 12 hrs of admittance, initial assessment, photographs, and Braden score were completed. Patients were re-examined every 4 days or at discharge from the unit, whichever came first. MAIN OUTCOME MEASURES: Determining risk factors for pressure ulcers, performing detailed statistical analyses, and testing the usefulness of the Braden score as a predictor of pressure ulcer risk. RESULTS: Twenty-three of 186 patients developed at least one pressure ulcer (incidence = 12.4%) after an average stay of 6.4 days. The Braden scale, which measures six characteristics of skin condition and patient status, proved to be a primary predictor of ulcer development. No ulcers developed in the 69 patients whose Braden score was 16 or higher. The likelihood of developing a pressure sore was predicted mathematically from the Braden score. However, being underweight was a significant and distinct factor in pressure ulcer development. CONCLUSIONS: Pressure ulcers may develop within the first week of hospitalization in the intensive care unit. Patients at risk have Braden scores of < or = 16 and are more likely to be underweight. These results suggest that aggressive preventive care should be focused on those patients with Braden scores of < or = 13 and/or a low body mass index at admission.

Adult↗

PubMed2001

Comparison of Chemicon SimulFluor direct fluorescent antibody staining with cell culture and shell vial direct immunoperoxidase staining for detection of herpes simplex virus and with cytospin direct immunofluorescence staining for detection of varicella-zoster virus.

A new rapid direct immunofluorescence assay, the SimulFluor direct fluorescent-antibody (DFA) assay, which can simultaneously detect herpes simplex virus types 1 and 2 (HSV-1 and -2) and varicella-zoster virus (VZV), was evaluated in comparison with our current standard procedures of (i) shell vial direct immunoperoxidase (shell vial IP) staining and cell culture for detection of HSV and (ii) cytospin DFA staining for VZV detection. A total of 517 vesicular, oral, genital, and skin lesion specimens were tested by all three procedures. For HSV detection, the SimulFluor DFA assay had an overall sensitivity, specificity, positive predictive value, and negative predictive value of 80.0, 98.3, 92.3, and 95.1%, respectively, when compared to culture. Shell vial IP staining had a sensitivity, specificity, positive predictive value, and negative predictive value of 87.6, 100, 100, and 96.9%, respectively, when compared with cell culture. The SimulFluor DFA assay, however, offers same-day, 1.5-hours results versus a 1- to 2-day wait for shell vial IP staining results and a 1- to 6-day wait for culture results for HSV. For VZV detection SimulFluor DFA staining detected 27 positive specimens as compared to 31 by our standard cytospin DFA technique--a correlation of 87.1%. A positive SimulFluor reaction for VZV is indicated by yellow-gold fluorescence compared to the bright apple-green fluorescence observed by cytospin DFA staining. There is no difference in turnaround time between the two assays. The SimulFluor DFA assay is a rapid immunofluorescence assay that can detect 80% of the HSV-positive specimens and 87% of the VZV-positive specimens with a 1.5-h turnaround time.

Animals↗

PubMed2000

Identification of flavone C-glycosides including a new flavonoid chromophore from barley leaves (Hordeum vulgare L.) by improved NMR techniques.

Six flavone C-glycosides were isolated from young leaves of barley. One of the C-glucosides has a new type of nucleus, a 2',4',5,5', 7-penta-OH-substituted flavone bearing a 6-C-beta-D-glucoside, which has apparently never been isolated before. One mono- and two di-C-glycosyl flavones were isolated for the first time from barley and identified as isoscoparin 7-O-beta-D-glucoside, carlinoside, and shaftoside, respectively. Other flavones were 7-O-beta-D-glucosides of isoorientin and isovitexin. The known problematic NMR structure elucidation of C-glycosyl flavonoids has been solved by using both a temperature close to the freezing point of the solvent (22.5 degrees C in DMSO-d(6)) and a high temperature (70, 90 degrees C) for comparison during NMR measurements. Structural determination of all the compounds was achieved by employing 1D and 2D NMR techniques.

Flavonoids↗

PubMed2000

Clinical long-term in vivo evaluation of poly(L-lactic acid) porous conduits for peripheral nerve regeneration.

It was the purpose of this study to evaluate the clinical long-term effects of PLLA degradation in vivo on nerve regeneration in the rat sciatic nerve model. Thirty-one Sprague Dawley rats were utilized. Two groups of animals were selected. The control group of 10 animals received a 12 mm reversed isograft into the right sciatic nerve from 5 donor animals. The experimental group (n = 21) received a 12 mm empty PLLA conduits placed into a 12 mm defect in the right sciatic nerve. The left leg served as an internal control. Walking track analysis was performed monthly through 8 months. At the end of 4 and 8 months, animals in the control isograft and experimental group had the medial and lateral gastrocnemius muscles harvested and weighed for comparison. The midconduit/isograft and the distal nerve in these same animals were harvested and histomorphologically analyzed. Multiple samples were collected and expressed as means +/- standard error. A two-sample t-test and Wilcoxon rank sum test was used to compare the variables. Significance level was set at alpha = 0.05. After Bonferroni correction for multiple testing, a p value of < or = 0.01 was considered statistically significant. Throughout all time periods, the PLLA conduit remained structurally intact and demonstrated tissue incorporation and vascularization. There was no evidence of conduit collapse or breakage with limb ambulation. Moreover, there was no evidence of conduit elongation at 8 months as previously observed with the 75:25 poly(DL-lactic-co-glycolic acid) (PLGA) conduits. The mean absolute value of the sciatic functional index (SFI) demonstrated no group differences from isograft controls measured over the 8 months except at 3 months where the isograft values were higher (p = 0.0379) and at 7 months were the isograft group was significantly lower (p = 0.0115). At 4 and 8 months, the weight of the gastrocnemius muscles of the experimental group was not significantly different from isografts. At 4 months the number of axons/mm2 and nerve fiber density was not significantly different between the isograft control and experimental groups in either the midconduit/isograft or distal nerve. At 8 months the number of axons/mm2 was significantly lower in the isograft compared to the midconduit experimental group (p = 0.006). The number of axons/mm2 in the distal nerve and the nerve fiber density in the midconduit and distal nerve were not significantly different between the two groups. The study confirmed our initial hypothesis that PLLA conduits are a viable scaffold for clinical long-term nerve gap replacement. We are critically aware however that longer evaluation of polymer degradation is warrented. Further studies on these individual nerve components are continuing, with the ultimate goal being the fabrication of a bioactive conduit that meets or exceeds the functional results of isografts.

Animals↗

PubMed2000

Comparison of the effectiveness of polymerase chain reaction and enzyme immunoassay in detecting Chlamydia trachomatis in different female genitourinary specimens.

BACKGROUND: In high-volume laboratories, enzyme immunoassay (EIA) is the most commonly used method of detecting Chlamydia trachomatis. The optimal specimen for detecting C trachomatis is a combined urethral and cervical swab. OBJECTIVE: To compare EIA with the combined urethral and cervical swab with polymerase chain reaction (PCR) on urine alone and urine mixed with cervical cells. PATIENTS AND METHODS: Phase 1 of the study included 752 sets of specimens used for comparison. In phase 2, another 212 samples of urine and urine plus cervical cells were added to the study for comparison of the 2 specimen types using PCR. RESULTS: In phase 1, 648 samples were negative and 76 were positive by all 3 methods and specimen combinations. Enzyme immunoassay was able to detect 81 positive samples (10.8%), whereas PCR on urine alone detected 97 positive samples (12.9%) and PCR on urine plus cervical cells detected 102 positive samples (13.6%), giving a sensitivity of 75%, 93.3%, and 98. 1% respectively. In phase 2, PCR on urine alone detected 119 positive samples (12.3%) and PCR on urine plus cervical cells detected 127 positive samples (13.1%), with a sensitivity of 92.2% and 98.5%, respectively. CONCLUSION: Polymerase chain reaction on urine alone or urine plus cervical cells is superior to EIA on combined cervical and urethral swabs. There is a slight advantage of adding cervical cells to the urine compared with the urine specimen alone when PCR is used as the assay for detection. The total inhibition rate in our female population is only 3.1% when PCR is used.

Cervix Uteri↗

PubMed2000

Performance characteristics of the Becton Dickinson ProbeTec System for direct detection of Chlamydia trachomatis and Neisseria gonorrhoeae in male and female urine specimens in comparison with the Roche Cobas System.

OBJECTIVE: The Becton Dickinson BDProbeTec ET System is a new semiautomated system using strand displacement amplification technology that simultaneously amplifies and detects Chlamydia trachomatis and Neisseria gonorrhoeae DNA. The strand displacement amplification products are hybridized with a fluorescent detector probe and are captured by a chemiluminescent assay in a microwell format. An amplification control is also included to monitor assay inhibition. This study evaluated the performance of the BDProbTec ET system in detecting C trachomatis and N gonorrhoeae in male and female urine specimens, calculated its ability to process large volumes of specimens, and determined the inhibition rate. MATERIALS AND METHODS: Eight hundred twenty-five male and 399 female urine specimens were tested for both C trachomatis and N gonorrhoeae with the BDProbeTec ET system, and results were compared with those of the Roche Amplicor Cobas system. All urine specimens were processed on both assays on the same day they were received, according to the manufacturers' instructions. Discrepant results were resolved by in-house polymerase chain reaction assays. Internal or amplification controls were also used in each specimen assay to monitor inhibition. The throughput of the BDProbTec ET system was further tested with 150 urine specimens on an 8-hour shift for 2 days. RESULTS: The overall sensitivity, specificity, positive predicative value, and negative predicative value for for detection of chlamydia were 95.3%, 99.3%, 95.9%, and 99.2% for strand displacement amplification and 95.9%, 98.3%, 90.6%, and 99.3% for the Roche Amplicor system. For detection of gonorrhea, these values were 100%, 99.7%, 88.2%, and 100% and 96.7%, 98.9%, 69%, and 99.9%, respectively. The overall inhibition rates for both strand displacement amplification and Roche Amplicor were less than 3.5%. The BDProbTec ET system was able to produce 150 results each for chlamydia and gonorrhea and the internal control within the 8-hour shift. CONCLUSIONS: The performance characteristics of the BDProbeTec ET assay are similar to those of the Roche Amplicor polymerase chain reaction for detection of chlamydia and gonorrhea in male and female urine specimens. The system was able to produce 300 results in an 8-hour shift.

Chlamydia trachomatis↗

PubMed1999

In vivo evaluation of poly(L-lactic acid) porous conduits for peripheral nerve regeneration.

The present study provides in vivo trials of poly(L-lactic acid) (PLLA) as a porous biodegradable nerve conduit using a 10 mm sciatic nerve defect model in rats. The PLLA conduits, fabricated by an extrusion technique, had an inner diameter of 1.6 mm, an outer diameter of 3.2 mm, and a length of 12 mm. They were highly porous with an interconnected pore structure (of 83.5% porosity and 12.1 microm mean pore size). The conduits were interposed into the right sciatic nerve defect of Sprague Dawley rats using microsurgical techniques; nerve isografts served as controls. Walking track analysis was performed after conduit placement monthly through 16 weeks. At the conclusion of 6 and 16 weeks, sections from the isograft/conduit and distal nerve were harvested for histomorphometric analysis. The right gastrocnemius muscle was also harvested and its weight was determined. All conduits remained intact without breakage. Moreover, no conduit elongated during the 16 weeks of placement. Walking track analysis and gastrocnemius muscle weight demonstrated increasing regeneration over the 16 weeks in both the conduit and isograft control groups, with control values significantly greater. The nerve fiber density in the distal sciatic nerve for the PLLA conduits (0.16+/-0.07) was similar to that for the control isografts (0.19+/-0.05) at 16 weeks. The number of axons/mm2 in the distal sciatic nerve for the PLLA conduits was lower than that for the isografts (13 800+/-2500 vs. 10700+/-4700) at 16 weeks. The results for PLLA were significantly improved over those for 75:25 poly(DL-lactic-co-glycolic acid) of a previous study and suggest that PLLA porous conduits may serve as a scaffold for peripheral nerve regeneration.

Animals↗