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Robert Duncan

Publications and source records attributed to Robert Duncan.

At least 19 recordsLinked to original sources
PubMed2006

Gene chromosomal organization and expression in cultured human neurons exposed to cocaine and HIV-1 proteins gp120 and tat: drug abuse and NeuroAIDS.

As a model for Neuropsychiatric dysfunction in NeuroAIDS due to HIV-1 infection and drug abuse, we analyzed gene expression in human neurons treated with cocaine and HIV-1 proteins tat and envelope (env). One-way ANOVA showed statistically significant genes among the treatment groups (p < or = 0.0005). The identified genes were then subjected to a "stepwise" analysis using a repeated measures ANOVA to discover genes with parallel response group profiles across the treatment conditions. These groups were then analyzed using a repeated measures ANOVA to assess treatment main effects and gene-by-treatment interactions within groups. One-way ANOVA produced 35 genes that were significantly associated across all treatment conditions. Factorial analysis of each gene found statistically significant differences: 30--tat, 17--cocaine, 10--env, 6--tat/env, 6--coc/env, and 4--coc/tat. Analyses across genes found three sets of four genes, one set of three genes, and three sets of two genes with parallel profiles. Identified genes had functions included signaling, immune related, and transcription control. The genes were not stochastically arranged on the chromosomes, were in proximity to each other, and to other genes involved in neuropsychiatric diseases. We hypothesize that these genes fall in transcriptionally isolated groups and that abused drugs and HIV-1 proteins trigger transcription overload, coerced expression that may result in damage to the chromosome's control and organization of chromatin transcription machinery.

AIDS Dementia Complex↗
PubMed2006

Cerebrospinal fluid from a 10-year-old dog with a single seizure episode.

A cerebrospinal fluid sample collected from the cerebellomedullary cistern of a 10-year-old Shetland Sheepdog with a recent history of seizures was submitted for fluid analysis and cytologic examination. Key findings included a total nucleated cell count of 520/microL (reference interval 0-5 cells/microL), with a predominance of mononuclear cells, a protein concentration of 51.8 mg/dL (reference interval 0-35 mg/dL), and a glucose concentration of 44.7 mg/dL (reference interval 52-105 mg/dL). There was marked atypia of the mononuclear cells, with abundant eosinophilic cytoplasm, marked anisocytosis and anisokaryosis, occasional binucleated cells, mitotic figures, and rare erythrophagia. The cytologic interpretation was marked, monocytoid-rich, mixed cell pleocytosis with cellular atypia worrisome for neoplasia. In addition to histiocytic neoplasia, differentials included granulomatous meningoencephalomyelitis, necrotizing meningoencephalitis, and granulomatous inflammation. The dog did not respond to anti-inflammatory and anticonvulsive therapy. At necropsy, a mass involving the meninges and subtending the neuropil of the right temporal lobe of the cerebrum was found. Histologically, the mass was composed of large, bizarre histiocytic cells with multinucleated forms and numerous mitotic figures. Using immunochemistry on cytologic and histologic samples, the pleomorphic histiocytic cells were positive for CD1c, CD11ad, CD45, lysozyme, and vimentin, and were negative for CD3, CD4, CD79a, CD90, and pancytokeratin. These findings supported a diagnosis of primary CNS malignant histiocytosis of dendritic antigen-presenting cell (CD1c+) origin. To our knowledge, this is only the third reported case of primary CNS histiocytic sarcoma in dogs, and the first to demonstrate strong immunochemical evidence for dendritic antigen-presenting cell origin.

Aging↗
PubMed2005

Cloning and characterization of angiotensin converting enzyme related dipeptidylcarboxypeptidase from Leishmania donovani.

We report the first identification, gene cloning, recombinant expression and biochemical characterization of an angiotensin converting enzyme (ACE) related dipeptidylcarboxypeptidase (DCP) in a protozoan parasite. The mammalian counterpart of this enzyme, peptidyl dipeptidase A (a carboxyl dipeptidase) also known as ACE leads to the cleavage of angiotensin I to produce a potent vasopressor. The catalytic enzyme activity of its Escherichia coli DCP counter part can be inhibited by the antihypertensive drug captopril, suggesting that this class of enzymes constitutes a novel target for drugs and vaccines. By utilizing a DNA microarray expression profiling approach, we identified a gene encoding a DCP enzyme for the kinetoplast protozoan Leishmania donovani (LdDCP) that was differentially expressed in promastigote and amastigote stages of the parasite life cycle. Both RNA and protein levels of LdDCP are higher in axenic amastigotes compared to promastigotes. Immuno-fluorescence analysis revealed the cytosolic expression of the protein. Primary structure analysis of LdDCP revealed the presence of an active Zn binding site. When expressed in E. coli, the recombinant enzyme showed carboxy-dipeptidase activity with synthetic substrates. Replacement of two histidine and one glutamic acid at positions 466, 470 and 467, respectively, with alanine residues in its active site resulted in loss of enzyme activity. Captopril, an ACE specific inhibitor was able both to reduce significantly LdDCP enzyme activity and to inhibit promastigote growth. Both its cytosolic location and close homology to DCPs from bacterial species suggests a role in parasite nutrition. Further, identification of LdDCP now provides an opportunity to investigate Leishmania peptidases for their potential as drug and vaccine targets.

Amino Acid Motifs↗
PubMed2005

Quantification of HIV GAG RNA using real time reverse transcriptase PCR.

Quantification of HIV-1 is important to quantify risk for disease progression as well as for acquiring infection associated with drug abuse. Prior quantification methods include immune and enzymatic procedures, e.g., quantifying HIV-1 p24 protein by ELISA and the Reverse Transcriptase by enzymatic assay. Improved quantification of HIV-1 RNA and cDNA was established using PCR. This paper describes a real-time PCR technique using the Applied Biosystems 5700 Sequence Detection System and Taqman reverse transcriptase PCR. We initially standardized the PCR method using ribosomal-RNA to obtain relative quantification. Pure gag RNA was used for standard curves, controls, and to obtain absolute RNA quantification. Pure HIV gag RNA was produced by T7-directed transcription of the plasmid pWISP98-85. Detailed statistical analyses describe using absolute standard curves, and intraassay and interassay coefficients of variation to validate the methods. The presented method is highly reproducible and the assay's performance is comparable to prior assays. The assay is validated with an 8-log range down to 80 copies.

DNA-Directed RNA Polymerases↗
PubMed2005

Increased risk of Pneumocystis carinii and community-acquired pneumonia with tobacco use in HIV disease.

OBJECTIVES: Tobacco smoking-related diseases continue to be of great health concern for the public, in general, and may be particularly deleterious for immunosuppressed HIV-positive individuals, who exhibit widespread tobacco use. METHODS: A total of 521 HIV-infected subjects consecutively admitted to Jackson Memorial Hospital between 2001-2002 were enrolled in the study. Research data included a medical history, details of tobacco and illicit drug use and complete computerized hospital information. Blood was drawn to obtain T lymphocyte profiles and viral load levels. Statistical analysis methods included Pearson, Student's t- and Chi-square tests and SAS Proc CATMOD. RESULTS: Tobacco use was prevalent, with 65% of the 521 HIV-positive hospitalized patients being current smokers. Overall, current tobacco users reported smoking an average of 15+/-13 cigarettes per day for an average of 15+/-14 years, with 40% smoking more than one pack per day. Pulmonary infections accounted for 49% of the total hospital admissions: 52% bacterial pneumonias, 24% Pneumocystis carinii pneumonia (PCP), 12% non-tuberculous mycobacterial diseases (NTM), 11% tuberculosis and 1% bronchitis. Many of the respiratory patients (46%) had been on highly active antiretroviral therapy (HAART) for over six months and 42% had received PCP and/or NTM prophylaxis. After matching the cases by HAART and CDC stage, the hazardous risk of being hospitalized with a respiratory infection was significantly higher for smokers than non-smokers (95% CI 1.33-2.83; p=0.003). Respiratory infections were noted in (37%) of the HAART-treated patients, and most (67%) occurred in smokers. CATMOD analyses controlling for HAART, viral load and CD4, indicated that HIV-infected smokers were three times more likely to be hospitalized with PCP and twice as likely to be hospitalized with community-acquired pneumonia than non-smokers, with increased risk related to the number of cigarettes/day in a dose-dependent manner. CONCLUSIONS: Tobacco use, which is widespread among HIV-infected subjects, increases the risk of pulmonary diseases, particularly PCP and CAP, two respiratory infections with high prevalence and morbidity risks even in the era of HAART.

Anti-HIV Agents↗
PubMed2005

A novel semiquantitative fluorescence-based multiplex polymerase chain reaction assay for rapid simultaneous detection of bacterial and parasitic pathogens from blood.

A multiplex polymerase chain reaction assay was developed for the rapid simultaneous detection of category A select bacterial agents (Bacillus anthracis and Yersinia pestis) and parasitic pathogens (Leishmania species) in blood using the Cepheid Smart Cycler platform. B. anthracis (Sterne) and Yersinia. pseudotuberculosis were used in the assay for optimization for B. anthracis and Y. pestis, respectively. The specificity of the target amplicons [protective antigen gene of B. anthracis and rRNA genes of other pathogens or human (internal control)] was evaluated by staining the amplicons with SYBR Green I and determining their individual melting temperatures (T(m)). As a novel approach for pathogen semiquantitation, the Tm peak height of the amplicon was correlated with a known standard curve of pathogen-spiked samples. This assay was able to detect DNA in blood spiked with less than 50 target cells/ml for all of the pathogens. The sensitivity of this assay in blood was 100% for the detection of Leishmania donovani from leishmaniasis patients and B. anthracis (Sterne) from symptomatic mice. The time necessary for performing this assay including sample preparation was less than 1.5 hours, making this a potentially useful method for rapidly diagnosing and monitoring the efficacy of drugs or vaccines in infected individuals.

Animals↗
PubMed2005

A multiplex polymerase chain reaction microarray assay to detect bioterror pathogens in blood.

Heightened concern about the dangers of bioterrorism requires that measures be developed to ensure the safety of the blood supply. Multiplex detection of such agents using a blood-screening DNA microarray is a sensitive and specific method to screen simultaneously for a number of suspected agents. We have developed and optimized a multiplex polymerase chain reaction microarray assay to screen blood for three potential bioterror bacterial pathogens and a human ribosomal RNA gene internal control. The analytical sensitivity of the assay was demonstrated to be 50 colony-forming units/ml for Bacillus anthracis, Francisella tularensis, and Yersinia pseudotuberculosis (surrogate for Yersinia pestis). The absence of any false-positives demonstrated high analytical specificity. Screening B. anthracis-infected mouse blood samples and uninfected controls demonstrated effectiveness and specificity in a preclinical application. This study represents proof of the concept of microarray technology to screen simultaneously for multiple bioterror pathogens in blood samples.

Animals↗
PubMed2005

Grace under fire.

Explore the source record for details and available documents.

Adaptation, Psychological↗
PubMed2005

The effect of Medicare health care systems on women with breast and cervical cancer.

OBJECTIVE: Two common health care delivery systems in the United States are fee-for-service and managed care systems, including health maintenance organizations (HMOs). Differences may exist in patient outcomes depending upon the health care delivery system in which they are enrolled. We evaluated possible differences in the stage at diagnosis for breast and cervical cancer between 2 Medicare health care delivery systems (ie, fee for service and HMO) over the period 1985-2001. METHODS: We used a linkage of 2 national databases: the Medicare database from the Centers for Medicare and Medicaid Services and the National Cancer Institute's Surveillance, Epidemiology, and End Results program database to evaluate differences in stage at diagnosis between HMO and fee for service for breast and cervical cancer. RESULTS: We studied 130,336 Medicare-aged women with breast cancer (83% Medicare fee for service) and 6,758 women with cervical cancer (87% Medicare fee for service). We found an earlier stage of diagnosis for HMO patients, which remained significant after adjusting for potential confounding variables. Women enrolled in HMOs with breast cancer were 17% more likely and those with cervical cancer 35% more likely to be diagnosed at an in situ stage of diagnosis than fee-for-service patients. It is of note that when women had other cancer diagnoses, no statistically significant differences were seen in stage at diagnosis for either cancer between fee-for-service and HMO patients. CONCLUSION: Differences exist in stage at diagnosis between Medicare patients enrolled in HMOs compared with fee for service. This is likely due in part to use of or access to care.

Aged↗
PubMed2005

Timing of cleft palate closure should be based on the ratio of the area of the cleft to that of the palatal segments and not on age alone.

BACKGROUND: Retrospective and prospective serial spatiotemporal investigations were carried out primarily to determine whether the ratio of the size of the posterior cleft space relative to the palatal surface area limited laterally by the alveolar ridges can be used to select the appropriate time for surgical closure of the palatal cleft space. Two subsamples were compared to determine whether the size of the palate and velocity of palatal development in well growing cases differ from those in cases treated by vomer flap surgery. The prospective investigation asked whether presurgical orthopedics increases the rate of palatal growth and palatal size. METHODS: Using the palatal casts of 242 male and female individuals from eight institutions in the United States and Western Europe that followed a variety of treatment protocols, separate serial analyses were conducted of well growing cases with excellent aesthetics, dental occlusion, and speech and a control series of 17 cases of various clefts of the lip and alveolus and/or soft palate but no clefts in the hard palate. Twelve groupings of cases were established depending on their institutional location and type of cleft. RESULTS: Among the various institutions in the study, palatal growth rates and size were statistically similar. Growth in the various clinical series (size, mm2) was less than that of the control series. The ratio of cleft space size to palatal surface area medial to the alveolar ridges was 10 percent or less at 18 months of age in most cases. There was no statistical difference in total surface size between groups, except for one series whose total growth size was least of all. Right and left lateral palatal segments, whether large or small, grew at the same rate. The sample of bilateral cases was too small for statistical comparisons. Presurgical orthopedics did not stimulate palatal growth. The coefficient of variance was less than 10 percent in all measurements. CONCLUSIONS: Delaying all cleft closure surgery until 5 years of age and older is unnecessary to maximize palatal growth. The best time to close the palatal cleft space is when the palatal cleft size is 10 percent or less of the total palatal surface area bounded laterally by the alveolar ridges. The 10 percent ratio generally occurs between 18 and 24 months but can occur earlier or later. There is more than one good type of palatal cleft closure surgery.

Age Factors↗
PubMed2005

Can near-infrared spectroscopy identify the severity of shock in trauma patients?

BACKGROUND: Our recent experimental study showed that peripheral muscle tissue oxygen saturation (StO2), determined noninvasively by near-infrared spectroscopy (NIRS), was more reliable than systemic hemodynamics or invasive oxygenation variables as an index of traumatic shock. The purpose of this study was to establish the normal range of thenar muscle StO2 in humans and the relationship between shock state and StO2 in trauma patients. METHODS: This was a prospective, nonrandomized, observational, descriptive study in normal human volunteers (n = 707) and patients admitted to the resuscitation area of our Level I trauma center (n = 150). To establish a normal StO2 range, an NIRS probe was applied to the thenar eminence of volunteers (normals). Subsequently, in a group of trauma patients, an NIRS probe was applied to the thenar eminence and data were collected and stored for offline analysis. StO2 monitoring was performed continuously and noninvasively, and values were recorded at 2-minute intervals. Five moribund trauma patients were excluded. Members of our trauma faculty, blinded to StO2 values, classified each patient into one of four groups (no shock, mild shock, moderate shock, and severe shock) using conventional physiologic parameters. RESULTS: Mean +/- SD thenar StO2 values for each group were as follows: normals, 87 +/- 6% (n = 707); no shock, 83 +/- 10% (n = 85); mild shock, 83 +/- 10% (n = 19); moderate shock, 80 +/- 12% (n = 14); and severe shock, 45 +/- 26% (n = 14). The thenar StO2 values clearly discriminated the normals or no shock patients and the patients with severe shock (p < 0.05). CONCLUSION: Decreased thenar muscle tissue oxygen saturation reflects the presence of severe hypoperfusion and near-infrared spectroscopy may be a novel method for rapidly and noninvasively assessing changes in tissue dysoxia.

Adult↗
PubMed2005

Development of ultrasound tomography for breast imaging: technical assessment.

Ultrasound imaging is widely used in medicine because of its benign characteristics and real-time capabilities. Physics theory suggests that the application of tomographic techniques may allow ultrasound imaging to reach its full potential as a diagnostic tool allowing it to compete with other tomographic modalities such as x-ray computer tomography, and MRI. This paper describes the construction and use of a prototype tomographic scanner and reports on the feasibility of implementing tomographic theory in practice and the potential of ultrasound (US) tomography in diagnostic imaging. Data were collected with the prototype by scanning two types of phantoms and a cadaveric breast. A specialized suite of algorithms was developed and utilized to construct images of reflectivity and sound speed from the phantom data. The basic results can be summarized as follows. (i) A fast, clinically relevant US tomography scanner can be built using existing technology. (ii) The spatial resolution, deduced from images of reflectivity, is 0.4 mm. The demonstrated 10 cm depth-of-field is superior to that of conventional ultrasound and the image contrast is improved through the reduction of speckle noise and overall lowering of the noise floor. (iii) Images of acoustic properties such as sound speed suggest that it is possible to measure variations in the sound speed of 5 m/s. An apparent correlation with x-ray attenuation suggests that the sound speed can be used to discriminate between various types of soft tissue. (iv) Ultrasound tomography has the potential to improve diagnostic imaging in relation to breast cancer detection.

Algorithms↗
PubMed2004

Tenofovir therapy for lamivudine resistance following liver transplantation.

BACKGROUND: Resistant hepatitis B virus (HBV) strains develop in 30% of liver transplant recipients treated with lamivudine within 2 years from the time of transplantation. OBJECTIVE: To assess safety and outcomes of tenofovir salvage therapy for patients with lamivudine resistance in a retrospective cohort of liver-transplanted patients. METHODS: Medical records were retrospectively evaluated for patients who received tenofovir. Data collected included demographics, HBV serologic information prior to and during tenofovir therapy, drug-related complications, and creatinine clearance. Criteria for lamivudine resistance included elevation of liver chemistries along with reappearance of hepatitis B surface antigen, hepatitis Be antigen, and/or HBV DNA. RESULTS: Sixteen patients showed resistance to lamivudine at 10-85 months (median 26) following liver transplantation. Tenofovir 300 mg/day orally was added in 8 patients 1-66 months after the development of viral lamivudine resistance and continued for 14-26 months (median 19.3). All 8 patients experienced HBV DNA viral suppression, with 7 currently nondetectable. No adverse events were reported, and creatinine clearance was not impaired. CONCLUSIONS: Our results suggest that tenofovir safely and markedly decreases replication of lamivudine-resistant HBV variants after liver transplantation and is another potential option for the treatment of HBV lamivudine resistance.

Adenine↗
PubMed2004

Comparison of the prognostic potential of hyaluronic acid, hyaluronidase (HYAL-1), CD44v6 and microvessel density for prostate cancer.

Despite the development of nomograms designed to evaluate a prostate cancer (PCa) patient's prognosis, the information has been limited to PSA, clinical stage, Gleason score and tumor volume estimates. We compared the prognostic potential of 4 histologic markers, hyaluronic acid (HA), HYAL-1-type hyaluronidase (HAase), CD44v6 and microvessel density (MVD) using immunohistochemistry. HA is a glycosaminoglycan that promotes tumor metastasis. CD44 glycoproteins serve as cell surface receptors for HA, and the CD44v6 isoform is associated with tumor metastasis. HYAL-1-type HAase is expressed in tumor cells and, like other HAases, degrades HA into angiogenic fragments. Archival PCa specimens (n=66) were obtained from patients who underwent radical prostatectomy for clinically localized PCa and had a minimum follow-up of 72 months (range 72-131 months, mean 103 months). For HA, HYAL-1 and CD44v6 staining and MVD determination, a biotinylated HA-binding protein, an anti-HYAL-1 IgG, an anti-CD44v6 IgG and an anti-CD34 IgG were used, respectively. HA and HYAL-1 staining was classified as either low- or high-grade. CD44v6 staining and MVD were evaluated quantitatively and then grouped as either low- or high-grade. Using 72 months as the cut-off limit for evaluating biochemical recurrence, HA, HYAL-1, combined HA-HYAL-1, CD44v6 and MVD staining predicted progression with 96%, 84%, 84%, 68% and 76% sensitivity, respectively. Specificity was, 61% (HA), 80.5% (HYAL-1), 87.8% (HA-HYAL-1), 56.1% (CD44v6) and 61% (MVD). Sensitivity and specificity values for each marker did not change significantly in a subset of 45 patients for whom follow-up of longer than 112 months was available. In univariate analysis using the Cox proportional hazards model, preoperative PSA, Gleason sum, margin status, seminal vesicle, extraprostatic extension (EPE), HA, HYAL-1, HA-HYAL-1 and MVD, but not CD44v6, age and clinical stage, were significant in predicting biochemical recurrence (p < 0.05). In multivariate analysis using stepwise selection, only preoperative PSA (hazard ratio/unit PSA change=1.086, p < 0.0001), EPE (hazard ratio=6.22, p=0.0016) and HYAL-1 (hazard ratio=8.196, p=0.0009)/HA-HYAL-1 (hazard ratio=5.191, p=0.0021) were independent predictors of biochemical recurrence. HA was an independent predictor of prognosis if HYAL-1 staining inference was not included in the multivariate model. In our retrospective study with 72- to 131-month follow-up, EPE, preoperative PSA and HYAL-1 either alone or together with HA (i.e., combined HA-HYAL-1) were independent prognostic indicators for PCa.

Biomarkers, Tumor↗
PubMed2004

Elevated expression of IFN-gamma in the HIV-1 infected brain.

We determined the extent of expression of three cytokines (IFN-gamma, IL-4, and TNF-alpha ) in brain tissue infected with human immunodeficiency virus-1 (HIV-1). The selections were IFN-gamma as a Th1 cytokine, IL- 4 as a Th2 cytokine, and TNF-alpha as a pro-inflammatory cytokine (and because of its prior implication in brain tissue damage due to HIV-1 infection). Based on current models for pathogenesis of HIV-1-associated dementia (HAD), in the periphery, Th1 cytokines are considered to be salutary, whereas Th2 cytokines are regarded as deleterious. However, we hypothesized that in the CNS these roles are reversed. Post-mortem temporal lobe tissue specimens from 16 HIV-1-seropositive patients and 11 HIV-1-seronegative controls were stained for IFN-gamma, IL-4, and TNF-alpha utilizing immunohistochemistry and alkaline phosphatase. HIV-1 infection causes alterations of brain cytokine expression that include increased IFN-gamma expression for HIV-1-seropositive vs. HIV-1-seronegative individuals. There was increased expression of IFN-gamma for HIV-1-seropositive individuals with or without HAD, with or without the broader category of neuropsychiatric impairment (NPI), and with or without opportunistic infections (OIs) compared to HIV-1-seronegatives. A significant inverse correlation between IFN-gamma vs. IL-4 in HIV-1-seropositives with HAD and in seronegative individuals was observed. There was an inverse correlation in seropositives between IFN-gamma vs. TNF-alpha, a positive trend with HAD, significant without HAD, significant with NPI and significant without OIs. Between IL-4 vs. TNF-alpha there was a correlation (trend) in seropositives, a trend with NPI, significant without NPI, and a trend without OI. Due to HIV-1 infection of the brain and neurological disease there is a prominent increased expression of IFN-gamma, an inverse expression of IFN-gamma vs. TNF-alpha, and TNF-alpha vs. IL-4. The inverse correlation between increased IFN-gamma and decreased IL-4 expression is consistent with the stimulation of activated macrophages, and T cells, greater toxicity in the HIV-1-infected brain, and is supportive of the significance of IFN-gamma in HIV-1-infected patients.

Adolescent↗
PubMed2004

Centrin gene disruption impairs stage-specific basal body duplication and cell cycle progression in Leishmania.

Centrin is a calcium-binding cytoskeletal protein involved in the duplication of centrosomes in higher eukaryotes. To explore the role of centrin in the protozoan parasite Leishmania, we created Leishmania deficient in the centrin gene (LdCEN). Remarkably, centrin null mutants (LdCEN(-/-)) showed selective growth arrest as axenic amastigotes but not as promastigotes. Flow cytometry analysis confirmed that the mutant axenic amastigotes have a cell cycle arrest at the G(2)/M stage. The axenic amastigotes also showed failure of basal body duplication and failure of cytokinesis resulting in multinucleated "large" cells. Increased terminal deoxy uridine triphosphate nick end labeling positivity was observed in centrin mutant axenic amastigotes compared with wild type cells, suggesting the activation of a programmed cell death pathway. Growth of LdCEN(-/-) amastigotes in infected macrophages in vitro was inhibited and also resulted in large multinucleated parasites. Normal basal body duplication and cell division in the LdCEN knockout promastigote is unique and surprising. Further, this is the first report where disruption of a centrin gene displays stage-specific/cell type-specific failure in cell division in a eukaryote. The centrin null mutant defective in amastigote growth could be useful as a vaccine candidate against leishmaniasis.

Animals↗
PubMed2004

Outcome of motorcycle riders at one year post-injury.

OBJECTIVE: There is little information about the long-term effects of injury on victims of motorcycle crashes. Following the repeal of the mandatory helmet law in Florida, we studied the impact of crashes on riders and their outcomes one year post-injury. SUBJECTS: All patients involved in a motorcycle crash over a six-month time period were assessed at one year post-injury. Demographic information, health status, motorcycle and helmet usage, and employability were surveyed. RESULTS: There were 94 patients evaluated at our center for the first six-month period following the repeal of the helmet law, where 50 (56%) were wearing a helmet at the time of injury. Of the 94, we were able to contact 45 (48%) at one-year follow up. Fourteen (31%) of those contacted were not wearing a helmet at the time of their crash. At one year post-injury, 23 (51%) reported physical deficits, while 39 (86%) were working. Only 12 (27%) were riding a motorcycle again, and 11 (92%) were wearing a helmet. CONCLUSIONS: Motorcycle riders at one year post-injury continue to experience physical deficits related to their accidents. There is a small percentage of riders that resume riding a motorcycle after injury. Being involved in a motorcycle accident has deterred the injured rider from riding a motorcycle again at one year post-injury.

Accidents, Traffic↗