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P Gibbs

Publications and source records attributed to P Gibbs.

At least 37 records · Page 2Linked to original sources
PubMed2002

Anthrax vaccine efficacy in golden Syrian hamsters.

The efficacy of a licensed human anthrax vaccine (anthrax vaccine adsorbed, AVA) was tested in golden Syrian hamsters against a virulent Bacillus anthracis spore challenge. Groups of golden Syrian hamsters were vaccinated at either 0 and 4 weeks or 0, 4 and 8 weeks, then challenged subcutaneously (s.c.) at 10 weeks with spores of various B. anthracis isolates. Although ELISA and toxin neutralization assays demonstrated high titers, none of the AVA-vaccinated hamsters were protected from challenge or demonstrated a significantly extended time to death compared to that of control animals. The results of the study demonstrate that the golden Syrian hamster is not an appropriate model for investigating human anthrax vaccine efficacy.

Animals↗
PubMed2001

Hyperuricemia, gout, and renal function after liver transplantation.

BACKGROUND: Hyperuricemia is a recognized complication of renal and cardiac transplantation, but the development of hyperuricemia and gout following liver transplantation have received less attention. We have retrospectively assessed the prevalence of hyperuricemia in 134 consecutive liver transplant recipients. RESULTS: Forty-seven percent of the liver transplant recipients studied had hyperuricemia. Serum creatinine was higher in hyperuricemic than in nonhyperuricemic patients. Peak uric acid correlated significantly with corresponding serum creatinine (rs=0.694). Only 6% developed gout. All the patients with gout and 10 hyperuricemic patients with renal impairment but without gout were treated with allopurinol. Over a median period of 3 months, mean serum creatinine fell from 177 micromol/l to 160 micromol/l (P=0.01), without change in type or dose of immuno-suppression. CONCLUSIONS: There is an important association between liver transplantation and hyperuricemia. Treatment with allopurinol results in a significant reduction in serum creatinine in patients with gout and in those with hyperuricemia and renal impairment.

Adult↗
PubMed2001

In vitro correlate of immunity in a rabbit model of inhalational anthrax.

A serological correlate of vaccine-induced immunity was identified in the rabbit model of inhalational anthrax. Animals were inoculated intramuscularly at 0 and 4 weeks with varying doses of Anthrax Vaccine Adsorbed (AVA) ranging from a human dose to a 1:256 dilution in phosphate-buffered saline (PBS). At 6 and 10 weeks, both the quantitative anti-protective antigen (PA) IgG ELISA and the toxin-neutralizing antibody (TNA) assays were used to measure antibody levels to PA. Rabbits were aerosol-challenged at 10 weeks with a lethal dose (84-133 LD(50)) of Bacillus anthracis spores. All the rabbits that received the undiluted and 1:4 dilution of vaccine survived, whereas those receiving the higher dilutions of vaccine (1:16, 1:64 and 1:256) had deaths in their groups. Results showed that antibody levels to PA at both 6 and 10 weeks were significant (P<0.0001) predictors of survival.

Administration, Inhalation↗
PubMed2001

Deletions in the 7a ORF of feline coronavirus associated with an epidemic of feline infectious peritonitis.

A population of Persian cats experienced an epidemic of feline infectious peritonitis (FIP) over 2 years. Twelve cases of FIP occurred in litters born during this period. Cats contracting FIP were all genetically related through the sire. Feline coronavirus (FCoV) genomic RNA was detected consistently in this study in biologic samples from adult cats, kittens suffering from FIP, and their siblings. Analysis of viral 7a/7b open reading frame (ORFs) were analyzed and revealed two distinct virus variants circulating in the population, one with an intact 7a ORF and one with two major deletions in the 7a ORF. The 7b ORFs were intact and similar among all virus isolates, although point mutations resulting in amino acid changes were present. The sire was determined to be infected with both variants, and was persistently virus-infected. We speculate the deletion variant arose from the non-deletion variant during viral replication in this population, possibly in the sire.

Amino Acid Sequence↗
PubMed2001

Management of primary cutaneous melanoma of the head and neck: The University of Colorado experience and a review of the literature.

BACKGROUND: While elective lymph node dissection (ELND), adjuvant radiation therapy and sentinel lymph node biopsy have all been advocated in the routine management of primary cutaneous melanoma arising in the head and neck, the optimal management has not been defined. METHODS: We have reviewed our experience of 273 patients with primary melanoma of the head and neck entered into a prospective database at the University of Colorado Health Sciences Center (UCHSC) from 1978 through 1998 and contrasted this with other reports in the literature. RESULTS: A total of 168 patients were identified that received their initial management at UCHSC and had no clinical evidence of distant disease. Only nine patients (5%) underwent ELND, and no patients received adjuvant radiation therapy. The local recurrence rate and 5-year melanoma specific survival, according to Breslow thickness, were similar to centers where adjuvant radiation therapy or ELND are routinely performed. Our preliminary experience and a review of the literature suggests that the technique of sentinel lymph node biopsy is an accurate and low risk procedure that provides valuable prognostic information useful in the further management of these patients. CONCLUSIONS: There is no clear indication that either ELND or adjuvant radiation therapy impacts on the outcome of patients with primary melanoma of the head and neck. Sentinel lymph node biopsy, in appropriate cases, is becoming the standard of care.

Adolescent↗
PubMed2001

Comparison of quantitative T2 mapping and diffusion-weighted imaging in the normal and pathologic prostate.

In this study, diffusion-weighted images of the human prostate were successfully obtained, enabling quantification of apparent diffusion coefficients (ADCs) in normal and pathologic regions. A dual acquisition fast spin-echo sequence was used for accurate T2 calculation. T2 values were significantly higher in the peripheral zone than the central gland (P = 0.015). No significant correlations were found in either normal or pathologic tissue between ADC values and relaxation rates for all three gradient directions and the orientationally averaged water diffusion coefficient. Evidence suggesting that diffusional anisotropy is present in normal prostatic tissue is also detailed, with significant differences noted between the z-component and both the x- and y-components of the ADC for peripheral zone (P < 0.040) and central gland (P < 0.001).

Adult↗
PubMed2001

Evaluation of enhanced haemolysis agar for detection of Listeria spp. and L. monocytogenes from production lines of fresh to cold-smoked fish.

Enhanced haemolysis agar (EHA) was compared to the two conventional Listeria isolation agars Oxford and PALCAM for its ability to detect Listeria spp. from production lines of fresh to cold-smoked fish. The ability of EHA for distinguishing L. monocytogenes colonies from other Listeria spp. was also evaluated.A total of 243 fish and environmental samples were analysed. Overall, 42 samples were found to contain Listeria spp. Only 34 samples were positive simultaneously by the three plating media. Two samples considered to be negative by the two conventional agars were found to be positive after isolation on EHA. All three selective agars were shown to be less effective in recovering Listeria spp. after primary enrichment in half-Fraser broth, compared to secondary enrichment in Fraser broth after 24 and 48 h. From 79 Listeria but presumptive negative L. monocytogenes colonies, EHA identified correctly 76 Listeria spp. and presented three false-negative results_three colonies further identified as L. monocytogenes but showing no noticeable haemolysis on EHA. Twenty-three of the thirty-three L. monocytogenes presumptive positive colonies, were confirmed positive and ten were identified as L. seeligeri. Despite its ability of distinguishing L. monocytogenes from the other Listeria spp., unless it is produced as a commercial medium, EHA cannot be an alternative to time-consuming classical identification because the preparation of this medium is both time and labour intensive.

Agar↗
PubMed2001

Characterization of Listeria monocytogenes isolated from production lines of fresh and cold-smoked fish.

AIMS: The aims of this study were to characterize strains of Listeria monocytogenes isolated from cold-smoking fish plants to establish possible routes of contamination through the processing chain. METHODS AND RESULTS: Listeria monocytogenes from fresh fish suppliers, raw materials, factory sites and finished products isolated in Portugal (162 isolates) and England (28 isolates) were characterized by serotyping, phage typing, tetracycline, cadmium and arsenic resistance, and plasmid profiling. On the basis of serotyping and phage typing, the isolates were categorized into eight groups. Although cultures within some of the groups could be further differentiated on the basis of plasmid profiling and cadmium and arsenite typing, consideration of all typing data predominantly clustered together isolates from a single location. L. monocytogenes strains: from fresh salmon suppliers were not found in the processing lines; from fresh salmon from different locations differed; and from the water where salmon trout were farmed differed from those isolated from the fish samples. SIGNIFICANCE AND IMPACT OF THE STUDY: No clear source or route of contamination in the cold-smoked processing chain could be established; however, these results highlight the complexity in tracking this bacterium through food chains.

Animals↗
PubMed2001

Hepatocellular carcinoma and chemoembolization.

BACKGROUND: Chemoembolization is often used in the treatment of hepatocellular carcinoma; however, there are limited data on its efficacy in an Australian setting. AIMS: To review retrospectively the experience of 21 patients with hepatocellular carcinoma who collectively had 36 chemoembolizations performed between October 1995 and February 1999 in a teaching hospital and liver transplant centre in Victoria. METHODS: Selective catheterization of the right or left hepatic arteries was performed. A mixture of cisplatin 50 mg, epirubicin 50 mg, mitomycin C 10 mg, Lipiodol and gelfoam was injected. Computed tomography (CT) scans were performed at baseline and at 1-3 months after chemoembolization. Outcome measures included response rates, toxicity, progression-free and overall survival. RESULTS: CT response rates: partial response 19% (n = 7), median duration 11 months (range 2+ to 37+); minor response 17% (n = 6), median duration 7 months (1+ to 12+); stable disease 42% (n = 15), median duration 3 months (1+ to 15 months); and progressive disease 22% (n = 8). Major toxicities included one case each of acute renal failure, contrast encephalopathy, gastric ulceration and hepatorenal failure. Median progression-free survival was 3 months (range 0-37+). Median overall survival was 15 months (range 6-50+). CONCLUSION: Chemoembolization has a role in the palliative treatment of hepatocellular carcinoma. Our response rates and toxicity data are consistent with those in the published literature. However, new treatments are needed and prevention of disease by reduction in the prevalence of chronic hepatitis B and C will be required to significantly reduce mortality from this tumour.

Adult↗
PubMed2001

Beneficial effects of converting liver transplant recipients from cyclosporine to tacrolimus on blood pressure, serum lipids, and weight.

Hypertension and hyperlipidemia are more prevalent after liver transplantation with cyclosporine as the primary immunosuppressive agent compared with tacrolimus. To determine whether blood pressure, serum lipid level, or weight improves when patients switch immunosuppression therapy, we retrospectively studied 26 liver transplant recipients with stable graft function who had been converted from cyclosporine to tacrolimus therapy with a median follow-up of 8 months. One of the 26 patients developed pruritus necessitating withdrawal of tacrolimus. The results therefore concern the remaining 25 patients. With the exception of a small decrease in bilirubin level (P <.05), there was no difference in graft or renal function after conversion. Mean systolic blood pressure decreased from 158 +/- 25 to 148 +/- 22 mm Hg over a mean of 8 +/- 3 months after conversion to tacrolimus (P =.015), whereas mean serum cholesterol level decreased from 5.3 +/- 0.9 to 4.9 +/- 0.9 mmol/L (P =.01). Sixty-eight percent of the patients lost weight, from a mean of 79.4 +/- 22.6 to 76.1 +/- 20.1 kg, in the 11 months after switching to tacrolimus therapy (P =.024). Serum triglyceride and blood glucose levels did not change, and no patient developed diabetes mellitus after conversion. These results indicate that switching from cyclosporine to tacrolimus can reduce blood pressure, serum cholesterol level, and weight after liver transplantation.

Blood Pressure↗
PubMed2001

Epithelioid hemangioendothelioma of the common femoral vein: Case report and review of the literature.

A young competitive skier had venous claudication. A stenosis of the left common femoral vein was revealed by means of an examination. Exploration and vein patch angioplasty were performed, and because of both the unusual appearance (focal thickening of vein wall) and the unclear etiology of the lesion, frozen and permanent sections of the wall were obtained. Epithelioid hemangioendothelioma, a rare intravascular sarcoma, was revealed by means of an examination of the permanent sections. Two additional procedures were required to completely excise the epithelioid hemangioendothelioma. We discuss these rare vascular malignancies and include a review of the available literature. Also, oncologic principles important in both the diagnosis and therapy of intravascular sarcomas are discussed.

Adult↗
PubMed2001

Nevi and melanoma: lessons from Turner's syndrome.

Females with Turner's syndrome (TS) have a markedly increased number of cutaneous nevi. While this is a well-recognized risk factor for cutaneous melanoma (CM), the incidence of this tumor in TS and the implications for our understanding of nevi and melanoma have not previously been considered. Here we report a case of an anorectal melanoma in a woman with TS and a review of the literature. Overall, there appears to be a lower than expected incidence of CM. Possible explanations are discussed and in particular the possible relationship between sex hormones and melanoma development as these girls fail to undergo normal pubertal development. Further study of this syndrome may provide important insights into the genetic factors involved in normal melanocyte and nevus development, the potential influence of sex hormones on melanoma development and the relationship between the presence of nevi and the risk of developing CM.

Adult↗
PubMed2001

Epidemiologic features of Campylobacter jejuni isolated from poultry broiler houses and surrounding environments as determined by use of molecular strain typing.

OBJECTIVE: To genetically type Campylobacter jejuni isolates from broiler houses or the external environment to identify the source of Campylobacter organisms in broiler chickens. SAMPLE POPULATION: Environmental samples associated with broiler chickens, in commercial grow-out houses. PROCEDURE: Polymerase chain reaction (PCR) was used to amplify flaB, and the amplicon was digested with Sau3A to create a restriction fragment length polymorphism assay; PCR was also used to detect a transcribed spacer region in the 23S rRNA gene. RESULTS: Isolates possessing a 23S spacer region were more prevalent outside broiler houses than inside. Houses that had previously contained chickens or lacked biosecurity procedures were more likely to contain isolates possessing the 23S spacer. One house contained only isolates possessing the spacer, whereas an adjacent house contained only isolates lacking the spacer. The flaB type detected in broiler houses was different from the type detected in the environment; however, many isolates within the broiler houses contained untypable flaB genotypes. CONCLUSIONS AND CLINICAL RELEVANCE: Most isolates from within houses were genetically distinct from isolates from outside houses that were examined by bacteriologic culture, suggesting an undetected source of C jejuni. Detection of isolates containing the 23S spacer appeared to be an indicator of environmental contamination of the houses. The observation of completely different C jejuni genetic types simultaneously within adjacent houses suggests that some types do not compete successfully during the grow-out period. In addition, the diversity of genotypes identified within broiler houses indicates the complexity of the ecologic features of C jejuni in the chicken environment.

Animals↗
PubMed2000

Bilateral open breast coil and compatible intervention device.

Dynamic contrast-enhanced breast MRI is an extremely sensitive method for breast lesion detection. For MR-only detected lesions it is essential that needle biopsy or localization prior to surgery is carried out under MR guidance. This work describes a bilateral open breast coil and prototype intervention device, which may be used in these situations. Results demonstrate that the open coil provides images superior to those obtained with a conventional closed breast coil. Initial phantom tests with the intervention device indicate a potential for this system to be used in the MR-guided localization of breast lesions. J. Magn. Reson. Imaging 2000;12:984-990.

Biopsy, Needle↗
PubMed2000

Evaluation of mini-VIDAS rapid test for detection of Listeria monocytogenes from production lines of fresh to cold-smoked fish.

This study was conducted to evaluate the efficacy of the mini-VIDAS Listeria monocytogenes (LMO) system (BioMérieux Vitek, Inc., Missouri, USA) for detection of L. monocytogenes in environmental and fish samples from three Portuguese cold-smoking plants and from their fresh fish suppliers. Mini-VIDAS-LMO is a fully automated system that uses fluorescent ELFA (Enzyme Linked Fluorescent Assay) technology for detection of Listeria monocytogenes antigens in food. It can be a rapid screening method alternative to time consuming classical isolation and identification. Two hundred and ninety five samples were tested in mini-VIDAS-LMO and in parallel by the ISO 11290-1 traditional protocol. The mini-VIDAS-LMO detected 8 of the 11 confirmed positive samples and presented 11 false positive results. The specificity of the mini-VIDAS-LMO found in this experiment was 0.96 and the sensitivity 0.73.

Animals↗
PubMed2000

Newer strategies for effective evaluation of primary melanoma and treatment of stage III and IV disease.

Our objective in this article is to update dermatologists on the clinical management of malignant melanoma, including the role of sentinel node biopsy and options for the treatment of stage III and stage IV disease. The role of the dermatologist throughout the continuum of care is emphasized, and the essential partnership with medical oncology in recognizing promising new options for patients with advanced disease is examined.

Antineoplastic Combined Chemotherapy Protocols↗