PubMed Health⌕ Search

Biomedical subjects

Chris Lee

Publications and source records attributed to Chris Lee.

11 recordsLinked to original sources
PubMed2006

A phase II, open label, monotherapy study of liposomal doxorubicin in patients with metastatic malignant melanoma.

PURPOSE: This phase II study explored the efficacy and tolerability of pegylated liposomal doxorubicin (PLD) given on a 2 week schedule in patients with advanced malignant melanoma previously untreated by chemotherapy. PATIENTS AND METHODS: Patients with inoperable, advanced melanoma were treated with Pegylated liposomal doxorubicin (Caelyx) at a dose of 20 mg/m(2) every 2 weeks. Treatment cycles were repeated every 4 weeks for a maximum of 6 cycles. Patients with responding or stable disease at the end of study treatment, as assessed by using NCI CTG criteria, could continue PLD off-study. RESULTS: PLD administered as a 2 weekly IV infusion was well tolerated with mild infusion reactions usually associated with the first infusion. Myelosuppression was mild, as was nausea and vomiting. Palmar plantar erythrodysesthesia was also uncommon using this schedule. There were no objective responses seen in the 14 evaluable patients. Enrollment was stopped as per protocol, due to lack of activity. CONCLUSION: PLD was well tolerated using a 2 week schedule but failed to show any activity in chemotherapy naive patients with advanced malignant melanoma.

Adult↗
PubMed2006

Blushing during social interactions in people with a fear of blushing.

Changes in facial blood flow were investigated during an introductory conversation, delivering a speech, and listening to the speech afterwards in 16 people with a fear of blushing and 16 controls. It was hypothesized that fear of blushing would be associated with high ratings of self-reported blushing intensity and embarrassment during the tasks, and with persistence of the blushing reaction between tasks. Embarrassment and self-reported blushing intensity were greater in the fear-of-blushing group than in controls throughout the experiment. Increases in facial blood flow were similar in the two groups during each of the tasks. However, blushing dissipated more slowly after each task in the fear-of-blushing group than in controls, resulting in an incremental increase in facial blood flow over the course of the experiment. The slow recovery after an episode of blushing might result in physiological or social cues that help to maintain a fear of blushing.

Adult↗
PubMed2006

Comparison of lateral locking plate and antiglide plate for fixation of distal fibular fractures in osteoporotic bone: a biomechanical study.

OBJECTIVES: The purpose of this study was to compare the biomechanical properties of posterolateral antiglide plating and lateral locked plating for fixation of displaced short oblique fractures of the fibula in osteoporotic bone. METHODS: Short oblique fractures of the distal fibula at the level of the syndesmosis were simulated with a fibular osteotomy and ligamentous sectioning in 18 paired fresh frozen ankles. The fractures were fixed with either a lateral locking plate with an independent lag screw or a posterolateral antiglide plate with a lag screw through the plate. The specimens were tested under a torsional load to failure. The torque to failure, angular rotation at failure, and construct stiffness of the two groups were compared. RESULTS: The torque to failure and construct stiffness were significantly greater on the side with the posterolateral antiglide plate than on the side with the the lateral locking plate (P = 0.01 and 0.005, respectively). CONCLUSIONS: The posterolateral antiglide plate demonstrated improved biomechanical stability as compared to the lateral locking plate in osteoporotic bone. In situations where fixation needs to be optimized, use of an antiglide plate may be favored over a lateral locking plate construct.

Aged↗
PubMed2005

Quantifying effects of ramp metering on freeway safety.

This study presents a real-time crash prediction model and uses this model to investigate the effect of the local traffic-responsive ramp metering strategy on freeway safety. Safety benefits of ramp metering are quantified in terms of the reduced crash potential estimated by the real-time crash prediction model. Driver responses to ramp metering and the consequent traffic flow changes were observed using a microscopic traffic simulation model and crash potential was estimated for a 14.8 km section of I-880 in Hayward, California and a hypothetical isolated on-ramp network. The results showed that ramp metering reduced crash potential by 5-37% compared to the no-control case. It was found that safety benefits of local ramp metering strategy were only restricted to the freeway sections in the vicinity of the ramp, and were highly dependent on the existing traffic conditions and the spatial extent over which the evaluation was conducted. The results provide some insight into how a local ramp metering strategy can be modified to improve safety (by reducing total crash potential) on longer stretch of freeways over a wide range of traffic conditions.

Accidents, Traffic↗
PubMed2005

Comprehensive analysis of vehicle-pedestrian crashes at intersections in Florida.

This study analyzes vehicle-pedestrian crashes at intersections in Florida over 4 years, 1999-2002. The study identifies the group of drivers and pedestrians, and traffic and environmental characteristics that are correlated with high pedestrian crashes using log-linear models. The study also estimates the likelihood of pedestrian injury severity when pedestrians are involved in crashes using an ordered probit model. To better reflect pedestrian crash risk, a logical measure of exposure is developed using the information on individual walking trips in the household travel survey. Lastly, the impact of average traffic volume on pedestrian crashes is examined. As a result of the analysis, it was found that pedestrian and driver demographic factors, and road geometric, traffic and environment conditions are closely related to the frequency and injury severity of pedestrian crashes. Higher average traffic volume at intersections increases the number of pedestrian crashes; however, the rate of increase is steeper at lower values of average traffic volume. Based on the findings in the analysis, some countermeasures are recommended to improve pedestrian safety.

Accidents, Traffic↗
PubMed2005

Insights on evolution of virulence and resistance from the complete genome analysis of an early methicillin-resistant Staphylococcus aureus strain and a biofilm-producing methicillin-resistant Staphylococcus epidermidis strain.

Staphylococcus aureus is an opportunistic pathogen and the major causative agent of numerous hospital- and community-acquired infections. Staphylococcus epidermidis has emerged as a causative agent of infections often associated with implanted medical devices. We have sequenced the approximately 2.8-Mb genome of S. aureus COL, an early methicillin-resistant isolate, and the approximately 2.6-Mb genome of S. epidermidis RP62a, a methicillin-resistant biofilm isolate. Comparative analysis of these and other staphylococcal genomes was used to explore the evolution of virulence and resistance between these two species. The S. aureus and S. epidermidis genomes are syntenic throughout their lengths and share a core set of 1,681 open reading frames. Genome islands in nonsyntenic regions are the primary source of variations in pathogenicity and resistance. Gene transfer between staphylococci and low-GC-content gram-positive bacteria appears to have shaped their virulence and resistance profiles. Integrated plasmids in S. epidermidis carry genes encoding resistance to cadmium and species-specific LPXTG surface proteins. A novel genome island encodes multiple phenol-soluble modulins, a potential S. epidermidis virulence factor. S. epidermidis contains the cap operon, encoding the polyglutamate capsule, a major virulence factor in Bacillus anthracis. Additional phenotypic differences are likely the result of single nucleotide polymorphisms, which are most numerous in cell envelope proteins. Overall differences in pathogenicity can be attributed to genome islands in S. aureus which encode enterotoxins, exotoxins, leukocidins, and leukotoxins not found in S. epidermidis.

Biofilms↗
PubMed2003

Treatment of women with low-grade squamous intraepithelial lesions on cytologic evidence or biopsy results by board-certified gynecologists.

OBJECTIVE: The Bethesda system combined human papillomavirus effects and mild dysplasia/cervical intraepithelial neoplasia grade 1 into a single category called low-grade squamous intraepithelial lesion. We sought to determine whether the treatment of women with low-grade squamous intraepithelial lesions by board-certified gynecologists was different for human papillomavirus effect versus mild dysplasia/cervical intraepithelial neoplasia grade 1. In addition, we sought to document the prevalence of human papillomavirus testing and counseling regarding sexual partners by this group of providers. STUDY DESIGN: A 2-page survey was mailed in April 1998 to a random sample of 491 fellows of the American College of Obstetrics and Gynecology. The response rate was 50.6%. RESULTS: For a Papanicolaou test with human papillomavirus effects, 52% of the respondents would perform colposcopy. For a Papanicolaou test with mild dysplasia/cervical intraepithelial neoplasia 1, 86% of the respondents would perform colposcopy (P <.0001). For biopsy-proved condyloma, 33% of the respondents would treat the patient. For biopsy-proved mild dysplasia/cervical intraepithelial neoplasia grade 1, significantly more respondents would treat the patient (45%, P =.02). Respondents rarely offered routine human papillomavirus testing and frequently made recommendations regarding partner examination and condom use. CONCLUSION: Board-certified gynecologists commonly treat women with a newly diagnosed low-grade squamous intraepithelial lesion Papanicolaou test with colposcopy and frequently differentiate between human papillomavirus effects and mild dysplasia/cervical intraepithelial neoplasia grade 1 in the treatment.

Adult↗
PubMed2002

Genome sequence of the dissimilatory metal ion-reducing bacterium Shewanella oneidensis.

Shewanella oneidensis is an important model organism for bioremediation studies because of its diverse respiratory capabilities, conferred in part by multicomponent, branched electron transport systems. Here we report the sequencing of the S. oneidensis genome, which consists of a 4,969,803-base pair circular chromosome with 4,758 predicted protein-encoding open reading frames (CDS) and a 161,613-base pair plasmid with 173 CDSs. We identified the first Shewanella lambda-like phage, providing a potential tool for further genome engineering. Genome analysis revealed 39 c-type cytochromes, including 32 previously unidentified in S. oneidensis, and a novel periplasmic [Fe] hydrogenase, which are integral members of the electron transport system. This genome sequence represents a critical step in the elucidation of the pathways for reduction (and bioremediation) of pollutants such as uranium (U) and chromium (Cr), and offers a starting point for defining this organism's complex electron transport systems and metal ion-reducing capabilities.

Amino Acid Sequence↗