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R Lee

Publications and source records attributed to R Lee.

At least 145 records · Page 8Linked to original sources
PubMed1998

Joint Task Force Algorithm and Annotations for Diagnosis and Management of Rhinitis.

The algorithm and text annotations in this document are intended to assist clinical decision making about patients who present with symptoms of rhinitis. This document complements the Executive Summary of Joint Task Force Practice Parameters for Diagnosis and Management of Rhinitis (Ann Allergy, Asthma, Immunol 1998; 81:463-468) and Diagnosis and Management of Rhinitis: Complete Guidelines of the Joint Task Force on Practice Parameters in Allergy, Asthma and Immunology (Ann Allergy, Asthma, Immunol 1998;81:478-578). The Joint Task Force on Practice Parameters in Allergy, Asthma and Immunology is co-sponsored by the American Academy of Allergy, Asthma and Immunology, the American College of Allergy, Asthma and Immunology and the Joint Council of Allergy, Asthma and Immunology.

Algorithms↗
PubMed1998

Diagnosis and management of rhinitis: complete guidelines of the Joint Task Force on Practice Parameters in Allergy, Asthma and Immunology. American Academy of Allergy, Asthma, and Immunology.

This document contains complete guidelines for diagnosis and management of rhinitis developed by the Joint Task Force on Practice Parameters in Allergy, Asthma and Immunology, representing the American Academy of Allergy, Asthma and Immunology, the American College of Allergy, Asthma and Immunology and the Joint Council on Allergy, Asthma and Immunology. The guidelines are comprehensive and begin with statements on clinical characteristics and diagnosis of different forms of rhinitis (allergic, non-allergic, occupational rhinitis, hormonal rhinitis [pregnancy and hypothyroidism], drug-induced rhinitis, rhinitis from food ingestion), and other conditions that may be confused with rhinitis. Recommendations on patient evaluation discuss appropriate use of history, physical examination, and diagnostic testing, as well as unproven or inappropriate techniques that should not be used. Parameters on management include use of environmental control measures, pharmacologic therapy including recently introduced therapies and allergen immunotherapy. Because of the risks to patients and society from sedation and performance impairment caused by first generation antihistamines, second generation antihistamines that reduce or eliminate these side effects should usually be considered before first generation antihistamines for the treatment of allergic rhinitis. The document emphasizes the importance of rhinitis management for comorbid conditions (asthma, sinusitis, otitis media). Guidelines are also presented on special considerations in patients subsets (children, the elderly, pregnancy, athletes and patients with rhinitis medicamentosa); and when consultation with an allergist-immunologist should be considered.

Diagnosis, Differential↗
PubMed1998

Intranasal immunization with yeast-expressed 19 kD carboxyl-terminal fragment of Plasmodium yoelii merozoite surface protein-1 (yMSP119) induces protective immunity to blood stage malaria infection in mice.

Variable protection against malaria blood-stage infection has been demonstrated in mice following parenteral immunization with the highly conserved 19 kD carboxylterminal fragment of the merozoite surface protein-1 (MSP119) using CFA/IFA and other adjuvants. Here we show that intranasal immunization of BALB/C mice with yeast expressed Plasmodium yoelii MSP119 plus a mixture of native and recombinant cholera toxin B subunit, could induce serum MSP119-specific antibodies at titres ranging from 20 000 to 2 560 000. The Ig subclass responses were predominantly G1 and G2b. Intranasal immunization led to protection following challenge (peak parasitaemia < 1%) in mice with the highest MSP119-specific titre (>/= 640 000). In two of the three protected mice, a peak parasitaemia of 0.1%-1% was followed by a boost of the antibody response whereas one of the three protected mice did not boost its antibody response after a peak parasitaemia of 0.02%. In unprotected mice, antibody levels rose, then fell, following the detection of parasites in the peripheral blood. CD4+ T cell-depletion abrogated the ability of the mice to boost their antibody response following challenge. These data demonstrate the potential for intranasal immunization with MSP119 to protect against malaria.

Adjuvants, Immunologic↗
PubMed1998

ESR studies of vitamin C regeneration, order of reactivity of natural source phytochemical preparations.

The effect of various flavonoids upon the ascorbate radical lifetime was investigated by ESR spectroscopy. The radical was generated via the reaction between ascorbic acid and ascorbate oxidase, the ascorbate radical being detected. The inclusion of the flavonoids in the ascorbic acid-ascorbate oxidase reaction mixture affected both the initial intensity of the ascorbate radical and its lifetime. Of the natural sources tested, Pycnogenol prolonged the ascorbate radical lifetime to the greatest extent, from a control value of 20 min to a maximum of 80 min with 200 micrograms/ml Pycnogenol. The flavonoids could either be regenerating ascorbic acid from ascorbate, or interacting with ascorbate oxidase, thus preventing ascorbic acid binding. When p-cresol, a known ascorbate oxidase inhibitor was added to the ascorbic acid-ascorbate oxidase reaction mixture, the ascorbate radical signal intensity was dramatically reduced and did not display the time-dependent decay observed with the flavonoids. This indicates that a direct interaction between the flavonoids and ascorbate radical occurs. Some of the flavonoids tested; myricetin, polyphenon and theaflavin appeared to compete with ascorbic acid for ascorbate oxidase, as they displayed saturation behaviour. By modifying the experimental conditions the myricetin radical was detected, thus confirming the direct interaction between myricetin and ascorbate oxidase.

Anthocyanins↗
PubMed1998

Inpatient emergencies encountered by an infectious disease consultative service.

The spectrum of infectious disease (ID) emergencies in hospitalized patients was assessed in a prospective study of 3,626 inpatient ID consultations in a 1,350-bed teaching hospital. ID emergencies, defined by a need or anticipated need for advanced life support or by irreversible organ damage leading to permanent functional loss, were encountered in 175 patients. Infections of the central nervous system (26.3%), cardiovascular system (14.9%), alimentary system (13.1%), and lower respiratory tract (7.4%) and adverse reactions to antimicrobial agents (7.4%) were most common. In 18.9% of the cases, the referring clinicians were unaware of the emergency at the time of referral. Drug reactions (46.1%), severe alimentary and peritoneal infections (32.0%), upper respiratory tract infections (28.6%), and skin and soft-tissue infections (27.3%) were most frequently missed. The emergency ID conditions were not recognized because they had an atypical presentation (51.5%), were not commonly seen in the referring specialty (24.2%), were due to rare organisms (15.2%), or had unusual anatomical sites of involvement (9.1%). A close liaison between clinicians and the ID team is crucial for recognition of ID emergencies at their early stages so that appropriate investigations and management can be instituted expediently, before the occurrence of irreversible damage.

Adult↗
PubMed1998

Pulsed-field gel electrophoresis of genomic digests demonstrates linkages among food, food handlers, and patrons in a food-borne Salmonella javiana outbreak in Massachusetts.

A total of 66 isolates of Salmonella javiana isolated from food, food handlers, and patrons that were epidemiologically linked to an outbreak of gastroenteritis were analyzed by pulsed-field gel electrophoresis. Analysis with restriction endonucleases XbaI and SpeI supported the epidemiologic association and suggested a pathway of transmission among food, food handlers, and patrons.

DNA, Bacterial↗
PubMed1998

Modification of the standard method used in the United Kingdom for counting Escherichia coli in live bivalve molluscs.

The standard method for counting Escherichia coli in live bivalve molluscs is labour intensive and takes three days to obtain a result. Modifications to the standard method were investigated in a collaborative trial conducted in five centres. No significant difference was found between results based on the presence of acid at 24 hours (h) in first stage tests and those based on the presence of acid and gas after 48 h (standard method). The use of the chromogenic medium BCIG (5-bromo-4-chloro-3-indolyl-beta-D glucuronide) agar incubated at 44 degrees C to confirm first stage tests was also found to give equivalent results to conventional confirmation tests. The preferred, modified method removes the presence of gas as a criterion of detection, uses a chromogenic agar medium to confirm the presence of E. coli, and gives results within 48 h. A distribution of simulated samples and selected strains of E. coli to other laboratories using the PHLS external quality assurance scheme for shellfish found no significant difference between results obtained by the standard and modified methods.

Animals↗
PubMed1998

Brachial plexus birth injuries and current management.

OBPP is a condition that, for the majority of patients, resolves spontaneously with appropriate nonoperative treatment. However, those patients who do not improve spontaneously now have a better chance for recovery owing to recent advances in microsurgery and nerve-transfer techniques. The most important aspect of therapy is timely recognition and referral.

Birth Injuries↗
PubMed1997

Hepatitis G virus coinfection in hepatitis C virus-infected liver transplant recipients.

BACKGROUND: In this study, we determined the prevalence of hepatitis G virus (HGV) infection in end-stage hepatitis C virus (HCV)-related liver disease and examined the influence of HGV coinfection on the outcome of liver transplantation. METHODS: HGV was detected by reverse transcriptase-polymerase chain reaction and Southern blotting in sera drawn from 159 patients who were known to be HCV infected before transplantation. Patients were followed up for a mean of 28.4 months after transplantation. RESULTS: Forty-one (25.3%) patients were HGV positive and the prevalence of HGV infection was similar for different HCV genotypes. Both HGV-positive and -negative groups had similar survival, recurrence rates, inflammatory activity scores, and degree of fibrosis at the time of recurrence. CONCLUSION: Infection with HGV is common in end-stage HCV-infected patients presenting for liver transplantation. It influences neither the outcome of liver transplantation nor the recurrence of hepatitis in the graft.

Adult↗
PubMed1997

Selective inhibition of l kappaB alpha phosphorylation and HIV-1 LTR-directed gene expression by novel antioxidant compounds.

Oxidative stress activates the NF-kappaB/Rel transcription factors which are involved in the activation of numerous immunoregulatory genes and the human immunodeficiency virus type 1 (HIV-1) long terminal repeat (LTR). In the present study, we examined the effects of established and novel compounds including antioxidants, ribonucleotide reductase inhibitors, and iron chelators on NF-kappaB activation and HIV LTR-mediated gene expression induced by TNF-alpha. N-Acetylcysteine (NAC), pyrrolidinedithiocarbamate (PDTC), and Trimidox (TD) at various concentrations inhibited TNF-alpha-induced NF-kappaB binding in Jurkat cells. Pretreatment of cells with these compounds prior to stimulation prevented I kappaB alpha degradation. Phosphorylation of I kappaB alpha, a prerequisite for its signal-induced degradation, was abrogated in these cells, indicating that oxidative stress is an essential step in the NF-kappaB activation pathway. On the other hand, iron chelators desferrioxamine, pyridoxal isonicotinoyl hydrazone (PIH), and salicylaldehyde isonicotinoyl hydrazone (SIH) showed no inhibition of TNF-alpha-induced NF-kappaB DNA-binding activity. Synergistic induction of HIV-1 LTR-mediated gene expression by TNF-alpha and the HIV-1 transactivator Tat in Jurkat cells was significantly suppressed in the presence of NAC and TD, but not PDTC. The inhibition of NAC and TD on LTR-directed gene expression was diminished when NF-kappaB-binding sites in the LTR were deleted, indicating that these compounds affected the NF-kappaB component of the synergism. Iron chelators PIH and SIH also showed some inhibitory effect on LTR-mediated gene activation, presumably through an NF-kappaB-independent mechanism. These experiments demonstrate that TD, at concentration 50 times lower than the effective concentration of NAC, potently inhibits NF-kappaB activity and suppresses HIV LTR expression.

Antioxidants↗
PubMed1997

Osteoprotegerin: a novel secreted protein involved in the regulation of bone density.

A novel secreted glycoprotein that regulates bone resorption has been identified. The protein, termed Osteoprotegerin (OPG), is a novel member of the TNF receptor superfamily. In vivo, hepatic expression of OPG in transgenic mice results in a profound yet nonlethal osteopetrosis, coincident with a decrease in later stages of osteoclast differentiation. These same effects are observed upon administration of recombinant OPG into normal mice. In vitro, osteoclast differentiation from precursor cells is blocked in a dose-dependent manner by recombinant OPG. Furthermore, OPG blocks ovariectomy-associated bone loss in rats. These data show that OPG can act as a soluble factor in the regulation of bone mass and imply a utility for OPG in the treatment of osteoporosis associated with increased osteoclast activity.

Amino Acid Sequence↗
PubMed1997

Hematopoietic stem cell-based gene therapy for acquired immunodeficiency syndrome: efficient transduction and expression of RevM10 in myeloid cells in vivo and in vitro.

Gene delivery via the hematopoietic stem cell (HSC) offers an attractive means to introduce antiviral genes into both T cells and macrophages for acquired immunodeficiency syndrome (AIDS) gene therapy. An amphotropic retroviral vector encoding a bicistronic gene coexpressing RevM10 and the murine CD8alpha' chain (lyt2) was developed to transduce HSC/progenitor cells. After transduction of CD34+ cells isolated from human umbilical cord blood, the lyt2 molecule detected by flow cytometry was used to monitor the level of gene transduction and expression and to enrich RevM10-expressing cells by cell sorting without drug selection. Using this quantitative method, high levels of gene transduction and expression (around 20%) were achieved by high-speed centrifugation of CD34+ cells with the retroviral supernatant (spinoculation). After reconstitution of human bone marrow implanted in SCID mice (SCID-hu bone) with the transduced HSC/progenitor cells, a significant number of donor-derived CD14+ bone marrow cells were found to express the RevM10/lyt2 gene. Finally, replication of a macrophage-tropic human immunodeficiency virus-type 1 (HIV-1) isolate was greatly inhibited in the lyt2+/CD14+ cells differentiated from transduced CD34+ cells after the enrichment of lyt2+ population. Thus, the RevM10 gene did not appear to inhibit the differentiation of HSC/progneitor cells into monocytes/macrophages. The level of retrovirus-mediated RevM10 expression in monocytes/macrophages derived from transduced HSCs is sufficient to suppress HIV-1 replication.

Acquired Immunodeficiency Syndrome↗
PubMed1997

Acute oral toxicity study of pyridostigmine bromide, permethrin, and DEET in the laboratory rat.

This study investigated the lethal interaction of pyridostigmine bromide (PB), permethrin, and DEET when given to adult male rats by gavage and was separated into two phases. Phase I determined the acute oral lethal dose-response relationship of each compound with the vehicle, propylene glycol. Phase II was divided into two portions: a dose-response study using probit units obtained from phase I [lethal dose (LD) 16, 30, 50, 70, and 84], and an interaction study that contained low levels (calculated LD16, additive LD32) of the two compounds while the concentration of the third compound was varied. Rats were fasted overnight, dosed, and observed for 14 d. A significant increase in lethality occurred when PB, permethrin, and DEET were given concurrently when compared to expected additive values. Furthermore, solutions containing PB and permethrin or PB and DEET also caused a significant increase in lethality when compared to expected additive values. This information suggests that lethality in this study was more than an additive effect.

Animals↗
PubMed1997

Identification of HIV-1 determinants for replication in vivo.

Pathogenic organisms are frequently attenuated after long-term culture in vitro. The mechanisms of the attenuation process are not clear, but probably involve mutations of functions required for replication and pathogenicity in vivo. To identify these functions, a direct comparison must be made between attenuated genomes and those that remain pathogenic in vivo. In this study, we used the heterochimeric SCID-hu Thy/Liv mouse as an in vivo model to define human immunodeficiency virus type 1 (HIV-1) determinants which are uniquely required for replication in vivo. The Lai/IIIB isolate and its associated infectious molecular clones (e.g., HXB2) were found to infect T cell lines but failed to replicate in the SCID-hu Thy/Liv model. When a lab worker was accidentally infected by Lai/IIIB, however, HIV-1 was isolated only from infection of primary PBMC, and not from infection of T cell lines. We hypothesized that the lab worker was exposed to a heterogeneous viral stock which had been attenuated by passage in immortalized T cell lines. Either a rare family member from this stock was selected for in vivo replication or, alternatively, an attenuated genotype dominant in vitro may have reverted to become more infectious in vivo. To address this hypothesis, we have used the SCID-hu Thy/Liv model to study the replication of HXB2 and of HXB2 recombinant viruses with HIV-1 fragments isolated from the infected lab worker. HXB2 showed no or very low levels of replication in the Thy/Liv organ. Replacement of its subgenomic fragment encoding the envelope gene with a corresponding fragment from the lab worker isolate generated a recombinant virus (HXB2/LW) which replicated actively in SCID-hu mice. The NEF mutation in the HXB2 genome is still present in HXB2/LW. Thus, the LW sequences encode HIV-1 determinants which enhance HIV replication in vivo in a NEF-independent mechanism. The specific determinants have been mapped to the V1-V3 regions of the HIV-1 genome. Six unique mutations in the V3 loop region of HXB2/LW have been identified which contribute to the increased replication in vivo.

Amino Acid Sequence↗
PubMed1997

Elephant trunk reconstruction for aberrant right subclavian and aortic aneurysm.

Although an aberrant right subclavian artery is the most common abnormality of aortic arch development, it is an unusual entity to encounter during repair of thoracic aortic aneurysms. A case of an aberrant right subclavian artery requiring reattachment during repair of an ascending aorta, aortic arch, and descending thoracic aortic aneurysm is reported. We report using the modified elephant trunk technique for surgically managing the aneurysm and aberrant right subclavian artery.

Aged↗
PubMed1997

Neurofibroma of the esophagus.

Benign esophageal tumors occur infrequently, with leiomyomas accounting for approximately 70% of cases. Benign neural tumors of the esophagus account for 200 cases reported in the literature and rarely require operative resection. The case of a 58-year-old woman with a 4-month history of progressive dysphagia and odynophagia is presented. A large intramural esophageal mass was resected through a right thoracotomy, and the esophagus was primarily repaired. Histologic examination revealed a neurofibroma.

Deglutition Disorders↗
PubMed1997

Distribution of infecting hepatitis C virus genotypes in end-stage liver disease patients at a large American transplantation center.

The distribution of hepatitis C virus (HCV) genotypes was studied in 202 anti-HCV-positive liver transplant candidates with end-stage liver disease. HCV sequences were successfully amplified from 185 patients: In the first 100, the genotype was determined by direct sequencing in the NS5 region, and in the remaining 85, type-specific primers were used for genotyping. Eighty-five patients (46.0%) were infected with type 1a HCV strains, 52 (28.1%) with type 1b, 14 (7.6%) with type 2b, 13 (7.0%) with type 4, 5 (2.7%) with type 3a, 2 (1.1%) with type 2a, and 1 (0.5%) with type 2c. Thirteen HCV-positive patients (7.0%) could not be genotyped. The relatively low prevalence of genotype 1b in this population of end-stage liver disease patients speaks against postulated higher pathogenicity of this genotype.

Adult↗