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C Landers

Publications and source records attributed to C Landers.

17 recordsLinked to original sources
PubMed2004

Proximate sources of bacteria on boneless loins prepared from routinely processed and detained carcasses at a pork packing plant.

Microbiological samples were obtained by swabbing detained and routinely processed pig carcasses before and after cooling, and sides, loin portions and loin cuts at various stages of the carcass breaking process. Aerobes, coliforms and Escherichia coli were enumerated in each sample. All three groups of bacteria were more numerous on detained than on routinely processed carcasses. Both trimming and cooling reduced the numbers of E. coli but not the numbers of aerobes on detained carcasses. After cooling, the log mean number of aerobes and E. coli on detained carcasses were each about 0.5 log unit more than the log mean numbers on routinely processed carcasses, but numbers of coliforms on the two types of carcass were similar. There were small increases in the numbers of coliforms and E. coli on carcasses during their movement from the cooler to the breaking facility. The numbers of bacteria on the meat apparently did not increase during the carcass-breaking process, although bacteria were redistributed on the product. Despite that, substantial numbers of bacteria were recovered from parts that do not contact food in cleaned conveying equipment used for carcass breaking. However, those bacteria included few coliforms and no E. coli. These findings suggest that the contamination of meat with E. coli from persistent detritus in carcass breaking equipment, such as has been found to occur at beef packing plants, may be prevented when carcass-breaking equipment and facilities are dried after cleaning, and wetting of equipment during processing is avoided.

Animals↗
PubMed2003

Effects of spray-cooling processes on the microbiological conditions of decontaminated beef carcasses.

Spray processes for cooling decontaminated carcasses were examined at four beef packing plants. Temperature histories were collected from deep leg sites on 25 carcasses and from randomly selected sites on the surfaces of a further 25 carcasses selected at random from carcasses undergoing cooling at each plant. Carcass cooling rates were similar at all four plants. Proliferation values calculated from surface temperature histories indicated similar increases of < or = 2 log units in the numbers of pseudomonads on carcasses at all plants and increases of <0.5 and >0.5 log units in the numbers of Escherichia coli on carcasses at plants A and B and plants C and D, respectively. The numbers of aerobes recovered from carcasses after cooling were about 1 log unit larger than the numbers recovered from carcasses before cooling at plants A, B, and C but >1.5 log units larger at plant D. These increases in numbers of aerobes were in agreement with the estimated proliferations of pseudomonads. The larger increase in the number of aerobes on carcasses at plant D may be attributable to carcasses not being pasteurized at that plant, while carcasses were pasteurized at all of the other plants. The numbers of E. coli recovered from carcasses after cooling at plants B, C, and D were also in agreement with the increases calculated from surface temperature histories. However, numbers of E. coli declined by about 1 log unit during carcass cooling at plant A. This decline may have been due to death occurring during chilling for some E. coli cells that were injured rather than killed by pasteurization with sprayed hot water at plant A, whereas pasteurization with steam at plants B and C seemingly left few injured E. coli cells. The growth of bacteria on decontaminated carcasses during spray cooling at the four plants was apparently constrained by temperature alone.

Animals↗
PubMed2001

Acute respiratory distress syndrome in pregnancy and the puerperium: causes, courses, and outcomes.

OBJECTIVE: To describe causes, courses, complications, and outcomes of patients with pregnancy-associated acute respiratory distress syndrome (RDS). METHODS: Twenty-eight women with ARDS during pregnancy or within a week postpartum formed the study population. Eight cases had been reported previously. Charts were abstracted for maternal demographics, etiology, and treatment of acute RDS, and maternal outcomes. For antepartum acute RDS, newborn charts were also reviewed. RESULTS: The incidence of acute RDS, excluding maternal transports, was one per 6277 deliveries or 0.016% (95% confidence interval [CI] 0, 0.027%). Leading causes were infection (12 cases), preeclampsia or eclampsia (seven cases), and aspiration (three cases). Eleven mothers died, a maternal mortality rate of 39.3% (CI 21.5%, 59.4%). Six of eight women who were ventilated for over 14 days survived. Nine of the acute RDS cases might have been preventable. Ten mothers with living fetuses were ventilated during the third trimester; nine delivered within 4 days. Among six infants delivered because of fetal heart rate abnormalities, one died and at least three had evidence of asphyxia. CONCLUSIONS: Acute RDS occurs more frequently in pregnancy than the 1.5 cases per 100,000 per year reported for the general population. Prolonged ventilator support is warranted. The high rate of perinatal asphyxia in infants who have fetal heart rate abnormalities supports a strategy of expeditious delivery during the third trimester.

Adolescent↗
PubMed2001

Potent inhibition of cytokine production from intestinal lamina propria T cells by phosphodiesterase-4 inhibitory thalidomide analogues.

In Crohn's disease, intestinal lamina propria (LP) T cells overproduce TNF-alpha and IFN-gamma, and clinical and animal studies indicate that this is pathogenic. Thalidomide influences cytokine production by leukocytes, inhibiting macrophage TNF-alpha, and is beneficial in treating Crohn's disease. Chemical analogues have been synthesized that may lack teratogenic and other side effects of thalidomide. We tested three analogues [selective cytokine inhibitory drugs (SelCIDs) A, B, and C, all potent PDE4 inhibitors] for effect on TNF-alpha, IFN-gamma, and IL-10 production by and on proliferation of intestinal LP mononuclear cells after T-cell stimulation and results were compared with those for peripheral blood leukocytes (PBL). While thalidomide itself had little effect, the SelCIDs were potent inhibitors, with relative inhibitory potencies: A> or =B>>C. The LP T cells were less sensitive to inhibition by the SelCIDs than were PBL. Since highly pre-activated PBL were even less sensitive, activation state alone can account for the responsiveness of intestinal LP T cells. Thalidomide analogues could play a role in treating Crohn's disease and other inflammatory disorders.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed2001

Molecular cloning of a Bacteroides caccae TonB-linked outer membrane protein identified by an inflammatory bowel disease marker antibody.

Commensal enteric bacteria are a required pathogenic factor in inflammatory bowel disease (IBD), but the identity of the pertinent bacterial species is unresolved. Using an IBD-associated pANCA monoclonal antibody, a 100-kDa protein was recently characterized from an IBD clinical isolate of Bacteroides caccae (p2Lc3). In this study, consensus oligonucleotides were designed from 100-kDa peptides and used to identify a single-copy gene from the p2Lc3 genome. Sequence analysis of the genomic clone revealed a 2,844-bp (948 amino acid) open reading frame encoding features typical of the TonB-linked outer membrane protein family. This gene, termed ompW, was detected by Southern analysis only in B. caccae and was absent in other species of Bacteroides and gram-negative coliforms. The closest homologues of OmpW included the outer membrane proteins SusC of Bacteroides thetaiotaomicron and RagA of Porphyromonas gingivalis. Recombinant OmpW protein was immunoreactive with the monoclonal antibody, and serum anti-OmpW immunoglobulin A levels were elevated in a Crohn's disease patient subset. These findings suggest that OmpW may be a target of the IBD-associated immune response and reveal its structural relationship to a bacterial virulence factor of P. gingivalis and periodontal disease.

Amino Acid Sequence↗
PubMed2000

Identification of a novel bacterial sequence associated with Crohn's disease.

BACKGROUND & AIMS: Enteric microorganisms are implicated in the pathogenesis of Crohn's disease (CD), but no clear bacterial or viral species has been identified. In this study, representational difference analysis (RDA) was used to isolate DNA segments preferentially abundant in lamina propria mononuclear cells of lesional mucosa vs. adjacent uninvolved mucosa. METHODS: Two RDA-derived microbial sequences were isolated (I1 and I2) and identified as novel homologues of the ptxR and tetR bacterial transcription-factor families. RESULTS: Quantitative competitive polymerase chain reaction of paraffin-embedded intestinal specimens from 212 patients showed that I2 DNA was present in many CD colonic lesions (43%), but was infrequent in other colonic specimens (9% of ulcerative colitis lesions and 5% of non-inflammatory bowel disease diseases; P<0.0001). I2 was prevalent in ileal specimens, regardless of disease status (43%-54%). Enzyme-linked immunosorbent assay analysis of 150 individuals with an I2 glutathione-S-transferase fusion protein showed frequent immunoglobulin A seroreactivity in CD (54% of patients), but infrequent seroreactivity in patients with ulcerative colitis, other inflammatory enteric diseases, or normals (10%, 19%, and 4%, respectively; P<0.001 to 0.00001). CONCLUSIONS: These findings relate CD to a novel lesion-localized and immunologically associated bacterial sequence, suggesting that the microorganism expressing the I2 gene product may be related to CD pathogenesis.

Amino Acid Sequence↗
PubMed1999

Identification of a novel mycobacterial histone H1 homologue (HupB) as an antigenic target of pANCA monoclonal antibody and serum immunoglobulin A from patients with Crohn's disease.

pANCA is a marker antibody associated with inflammatory bowel disease (IBD), including most patients with ulcerative colitis and a subset with Crohn's disease. This study addressed the hypothesis that pANCA reacts with an antigen(s) of microbial agents potentially relevant to IBD pathogenesis. Using a pANCA monoclonal antibody, we have previously identified the C-terminal basic random-coil domain of histone H1 as a pANCA autoantigen. BLAST analysis of the peptide databases revealed H1 epitope homologues in open reading frames of the Mycobacterium tuberculosis genome. Western analysis of extracts from six mycobacterial species directly demonstrated reactivity to a single, conserved approximately 32-kDa protein. Direct protein sequencing, followed by gene cloning, revealed a novel 214-amino-acid protein, an iron-regulated protein recently termed HupB. Sequence analysis demonstrated its homology with the mammalian histone H1 gene family, and recombinant protein expression confirmed its reactivity with the 5-3 pANCA monoclonal antibody. Binding activity of patient serum immunoglobulin G (IgG) to HupB did not correlate with reactivity to histone H1 or pANCA, indicating the complex character of the pANCA antigen. However, anti-HupB IgA was strongly associated with Crohn's disease (P < 0.001). These findings indicate that the 5-3 pANCA monoclonal antibody detects a structural domain recurrent among mycobacteria and cross-reactive with a DNA-binding domain of histone H1. The association of HupB-binding serum IgA with IBD provides new evidence for the association of a mycobacterial species with Crohn's disease.

Amino Acid Sequence↗
PubMed1997

Genetic markers may predict disease behavior in patients with ulcerative colitis.

BACKGROUND & AIMS: Recent studies have suggested that HLA DRB1*0103 and allele 2 of the interleukin 1 receptor antagonist (IL-1RA) gene predict severe and extensive ulcerative colitis, respectively. The aim of this study was to test these hypotheses in patients undergoing surgery for their colitis. METHODS: HLA DRB1 and DQB1 genotyping was performed in 99 patients and 472 controls. Genotyping for polymorphisms of genes encoding tumor necrosis factor alpha and IL-1RA was performed in 107 patients and 89 controls. Measurement of antineutrophil cytoplasmic antibody (ANCA) was performed in 72 patients and 58 healthy subjects by fixed neutrophil enzyme-linked immunosorbent assay and indirect immunofluorescence. RESULTS: The DRB1*0103 allele was increased in patients (14.1% vs. 3.2% in controls; P < 1 x 10[-5]). This association was greatest in patients with extensive disease (15.8%; P < 0.0001) or extraintestinal manifestations (22.8%; P < 0.0001): mouth ulcers (25.8%; P < 0.0001), arthritis (27.2%; P < 0.0001), and uveitis (35.7%; P < 0.0001). The DRB1*04 alleles were reduced in patients (P = 0.005). Differences were noted between extensive and distal disease in the frequency of allele 2 of IL-1RA (10.9% in distal vs. 28.6% in extensive; P = 0.01) and allele 2 homozygosity. ANCA was detected in 76.4% of patients. Carriage of IL-1RA allele 2 and tumor necrosis factor 2 allele was increased in ANCA-positive patients. CONCLUSIONS: Genetic markers may predict disease behavior in ulcerative colitis.

Adolescent↗
PubMed1995

High-titer antineutrophil cytoplasmic antibodies in type-1 autoimmune hepatitis.

BACKGROUND/AIMS: Autoimmune hepatitis (AIH), an unresolving liver inflammation characterized by periportal hepatitis and presence of serum autoantibodies, is distinguished by smooth muscle antibody and/or antinuclear antibody seropositivity. Type-2 AIH is characterized by antibodies to liver/kidney microsome type-1. Antineutrophil cytoplasmic antibodies (ANCAs) are highly specific for ulcerative colitis, primary sclerosing cholangitis, and, in this report, type-1 AIH determined by positive enzyme-linked immunosorbent assay confirmed by perinuclear indirect immunofluorescence staining. The studies described characterize the frequency and nature of ANCA in severe type-1 AIH patients and define AIH-ANCA specificity and diagnostic significance. METHODS: One hundred four patients, characterized by clinical, immunoserological, virological, histological, and antigenic criteria, were studied. ANCA expression was assayed by enzyme-linked immunosorbent assay. RESULTS: High-titer ANCA is present in 96% of patients with type-1 AIH with 92% showing a perinuclear staining pattern (pANCA). Whereas many patients were seropositive for antinuclear antibodies, the titer of ANCA did not correlate with the titer of antinuclear antibodies. ANCA expression did not correlate with the presence or absence of other autoimmune disorders. Finally, 80% of patients with AIH examined expressed only immunoglobulin G1 pANCA contrasting with the 33% of patients with PSC with pANCA subclass specificity. CONCLUSIONS: The presence of ANCA seems to be an independent and selective marker for type-1 AIH.

Adolescent↗
PubMed1993

Ulcerative colitis: a genetically heterogeneous disorder defined by genetic (HLA class II) and subclinical (antineutrophil cytoplasmic antibodies) markers.

Newly described distinct associations of HLA class II genes with ulcerative colitis (UC) (DR2) and Crohn's disease (CD) (DR1/DQ5) provide strong evidence for genetic heterogeneity of susceptibility between these two forms of inflammatory bowel disease. A familial distribution of antineutrophil cytoplasmic antibodies (ANCAs, a subclinical marker of UC) in UC families has further implied the existence of heterogeneity within UC. To test the hypothesis that the heterogeneity within UC indicated by ANCAs has a genetic basis that resides within the HLA region, we studied 89 UC cases and an ethnically matched control group (n = 50). Serological and molecular typing techniques were applied to define HLA class II genes (DR, DQ). ANCAs were detected using an enzyme-linked immunosorbent assay, and positive values were confirmed by indirect immunofluorescence. We observed that ANCA-positive UC patients (n = 70) had a significantly increased frequency of DR2 compared with ANCA-negative controls (n = 46) (44% vs 22%, P = 0.01). In contrast, the frequency of DR2 in ANCA-negative UC cases (21%) was virtually identical to that in controls (22%, P = 0.9). Furthermore, the ANCA-negative UC patients had an increase in the DR4 allele compared with ANCA-positive UC (P = 0.004). Thus, with the combination of a subclinical marker (ANCAs) and molecular genetic markers, genetic heterogeneity has been demonstrated within UC: ANCA-positive UC associated with DR2, and ANCA-negative UC likely associated with DR4.

Adult↗
PubMed1990

A distinct subset of antineutrophil cytoplasmic antibodies is associated with inflammatory bowel disease.

Antineutrophil cytoplasmic antibodies (ANCAs) have recently been demonstrated to be of importance in Wegener's granulomatosis and certain other forms of vasculitis associated with glomerulonephritis. With a fixed-cell ELISA, we demonstrated that ANCAs occur in the serum of patients with inflammatory bowel disease (IBD) involving the colon. In a blinded study, sera from 21 of 25 patients with ulcerative colitis (UC) and five of 25 patients with Crohn's disease had binding in the fixed-cell ELISA. The five reactive sera from patients with Crohn's disease were associated with the presence of clear colonic involvement. The presence of ANCA in patients with UC was not influenced by disease distribution or activity. Indeed, such antibodies were present in four subjects with UC more than 5 years after colectomy. The IBD-associated ANCAs were distinct from ANCAs reported in patients with Wegener's granulomatosis since the pattern of staining on indirect immunofluorescence exhibited a nongranular perinuclear distribution (P-ANCA). The P-ANCA observed in IBD did not react with myeloperoxidase and thus was distinct from the P-ANCA observed in vasculitis with cresentric glomerulonephritis. IBD and, in particular, UC, is associated with a distinct subset of P-ANCA, which may have important diagnostic and potential pathophysiologic implications.

Adult↗
PubMedDate not supplied

Cholesterol screening in a community health promotion program: epidemiologic results from a biracial population.

The prevalence and interrelationship of high blood cholesterol levels with other cardiovascular disease risk factors were studied in a biracial suburb of New York City. Participants in community-based screenings to determine blood cholesterol levels have been predominantly white women in older age groups, highly educated and nonsmokers. To reach a more representative segment of a local population and promote healthy lifestyle behaviors, cholesterol screenings were conducted within an ongoing health promotion program in Mount Vernon, NY. Plasma cholesterol levels were determined for 5,011 participants, including 2,308 whites and 1,778 blacks. Of the men, 29 percent had high cholesterol levels; among women, it was 27 percent. Of the men with high levels, half had levels greater than 200 milligrams per deciliter, as did 55 percent of the women. After statistical adjustments were made for age and other risk factors for high blood cholesterol, mean cholesterol levels were higher for whites than blacks. The level for white men was 204 milligrams per deciliter; for women, 212. For black men, the level was 199 milligrams per deciliter; for women, 208, P < .10. Hispanic men had levels of 199, P < .10. The levels for Hispanic women (203 milligrams per deciliter) were significantly lower than that of white women. Among whites who smoked more than 1 pack of cigarettes per day, mean cholesterol levels were 11 milligrams per deciliter higher than for those who never smoked or were light smokers (0, 1-20 cigarettes per day, P < .10). There were too few who smoked more than 1 pack to test this association adequately among blacks. The mean cholesterol levels for hypertensive black men were 10 milligrams per deciliter greater than for black men with normal blood pressure (P<.10).

Adult↗