Biomedical subjects

J K Collins

Publications and source records attributed to J K Collins.

At least 37 records · Page 2Linked to original sources

PubMed2001

Fas ligand upregulation is an early event in colonic carcinogenesis.

BACKGROUND/AIMS: Fas ligand (FasL) is a mediator of apoptosis via the Fas receptor (Fas/CD95/APO-1). Normal colonic epithelium expresses Fas, and appears to be relatively sensitive to Fas mediated apoptosis. Colonic adenocarcinomas coexpress FasL and Fas without undergoing widespread apoptosis. This study investigates the expression of FasL in colonic carcinogenesis from the earliest stages of the adenoma-carcinoma sequence. METHODS: FasL expression was determined in colonic adenomas (n = 38) of varying degrees of dysplasia and histological type by immunohistochemistry. Adenomas that contained areas of carcinomatous change were included (n = 12 of 38). Normal colonic epithelium (n = 10), hyperplastic polyps (n = 8), and serrated adenomas (n = 3) from patients without colonic adenocarcinomas were used for comparison. Cell death was detected in situ in adenomas using TUNEL (terminal transferase mediated dUTP nick end labelling). RESULTS: In normal colonic epithelium and hyperplastic polyps, FasL expression was restricted to the luminal surface of the crypts, where Fas-FasL coexpression was coincident with a high frequency of TUNEL positive epithelial cells. All adenomas (n = 38) had an altered distribution of positive FasL staining; FasL expression was found in most cells (> 70% of neoplastic cells). Expression of Fas was also detected throughout the adenomas, but coexpression of FasL and Fas was not associated with TUNEL positivity in most cells. CONCLUSIONS: FasL upregulation occurs early in the adenoma-carcinoma sequence of colon carcinogenesis, and is evident at the level of mild dysplasia. The lack of pronounced apoptosis in areas of adenomas coexpressing Fas and FasL suggests that colonocytes acquire resistance to Fas mediated apoptosis early in the transformation process.

Adenoma↗

PubMed2001

Serologic evaluation, efficacy, and safety of a commerical modified-live canine distemper vaccine in domestic ferrets.

OBJECTIVE: To determine efficacy and safety of a commercial modified-live canine distemper virus (CDV) vaccine used for prophylaxis in domestic ferrets. ANIMALS: Sixteen 16-week-old neutered male ferrets. PROCEDURES: Equal groups of ferrets were inoculated subcutaneously at 16 and 20 weeks of age with saline (0.9% NaCl) solution or a vaccine derived from the Onderstepoort CDV strain and attenuated in a primate cell line. Live virulent CDV was administered to all ferrets intranasally and orally 3 weeks after the second inoculation. Clinical signs and body weights were monitored regularly during the study. Blood samples for serologic examination were drawn prior to each inoculation, before challenge exposure, and 10, 15, and 21 days after exposure. Blood samples for reverse transcriptase polymerase chain reaction (RT-PCR) were obtained 5 days after the first vaccination, and 5, 10, 15, and 21 days after challenge exposure. RESULTS: After challenge exposure, control ferrets had significantly more clinical signs and weight loss, compared with vaccinates. All vaccinated ferrets survived, whereas all control ferrets died. The RT-PCR assay was successful in detecting CDV in blood and fresh or formalin-fixed tissues from infected ferrets. CONCLUSIONS AND CLINICAL RELEVANCE: Findings suggest that the vaccine when given SC to domestic ferrets as directed is safe and protective against challenge exposure with virulent CDV. The RT-PCR assay may simplify detection of CDV in fresh and fixed tissues.

Animals↗

PubMed2001

Gradient diffusion antibiotic susceptibility testing of potentially probiotic lactobacilli.

Minimum inhibitory contentrations (MICs) of selected inhibitors of cell wall synthesis (benzylpenicillin, ampicillin, and vancomycin), protein synthesis (gentamicin, streptomycin, tetracycline, chloramphenicol, and erythromycin), and nucleic acid synthesis (co-trimoxazole, rifampicin, and metronidazole) were determined by gradient diffusion (E test; AB Biodisk, Solna, Sweden) on deMan, Rogosa, Sharpe (MRS) agar for Lactobacillus strain GG and 11 closely related, rapidly growing, facultatively anaerobic, potentially probiotic Lactobacillus rhamnosus strains. All strains were resistant to vancomycin (MIC90 > or = 256 microg/ml), co-trimoxazole (MIC90 > or = 32 microg/ml), metronidazole (MIC90 > or = 32 microg/ml), gentamicin (MIC90 > or = 128 microg/ml), and streptomycin (MIC90 > or = 256 microg/ml), and sensitive to pencillin G (MIC90 > 0.375 microg/ml), ampicillin (MIC90 > 0.750 microg/ml), rifampicin (MIC90 > 0.375 microg/ml), tetracycline (MIC90 > 1.5 microg/ml), chloramphenicol (MIC90 > 8 microg/ml), and erythromycin (MIC90 > 2 microg/ml). E test MICs were also determined for L. acidophilus National Collection of Food Bacteria (NCFB) 1748 and L. reuteri Deutsche Sammlung von Mikroorganismen 20016T by the inoculum application method recommended by the manufacturer (swabbing), with and without antibiotic prediffusion for 1 h at room temperature, and by an alternative inoculum application (agar overlay) method, without antibiotic prediffusion. Antibiotic prediffusion increased the MICs for penicillin G, ampicillin, tetracycline, and chloramphenicol by up to 2 log2 MIC dilutions without changing antibiotic susceptibility category. Agar overlay application also increased the MICs for these antibiotics as well as for gentamicin by up to 3 log2 MIC dilutions without changing antibiotic susceptibility category. Exact agreement between MICs determined by swab and agar overlay application without antibiotic prediffusion was strain dependent: 54.5% for strain DSM 20016T and 72.7% for strain NCFB 1748. The swab and agar overlay gradient diffusion methods provide a reliable basis for antibiotic susceptibility testing of rapidly growing, facultatively anaerobic lactobacilli, using MRS agar as test medium and are readily applicable for testing individual isolates as needed.

Anti-Bacterial Agents↗

PubMed2000

Interferon-gamma sensitizes colonic epithelial cell lines to physiological and therapeutic inducers of colonocyte apoptosis.

Homeostasis in the colonic epithelium is achieved by a continuous cycle of proliferation and apoptosis, in which imbalances are associated with disease. Inflammatory bowel disease (IBD) and colon cancer are associated with either excessive or insufficient apoptosis of colonic epithelial cells, respectively. By using two colonic epithelial cell lines, HT29 and SW620, we investigated how the epithelial cell's sensitivity to apoptosis was regulated by the proinflammatory cytokine interferon-gamma (IFN-gamma). We found that IFN-gamma sensitized HT29 cells, and to a lesser extent SW620, to diverse inducers of apoptosis of physiologic or therapeutic relevance to the colon. These apoptosis inducers included Fas (CD95/APO-1) ligand (FasL), short-chain fatty acids, and chemotherapeutic drugs. The extent of IFN-gamma-mediated apoptosis sensitization in these two cell lines correlated well with the degree of IFN-gamma-mediated upregulation of the proapoptotic protease caspase-1. Although IFN-gamma alone effectively sensitized HT29 cells to apoptosis, inclusion of the protein synthesis inhibitor cyclohexamide (CHX) during apoptotic challenge was necessary for maximal sensitization of SW620. The requirement of CHX to sensitize SW620 cells to apoptosis implies a need to inhibit translation of antiapoptotic proteins absent from HT29. In particular, the antiapoptotic protein Bcl-2 was strongly expressed in SW620 cells but absent from HT29. Our results indicate that IFN-gamma increases the sensitivity of colonic epithelial cells to diverse apoptotic stimuli in concert, via upregulation of caspase-1. Our findings implicate caspase-1 and Bcl-2 as important central points of control determining the general sensitivity of colonic epithelial cells to apoptosis.

Antineoplastic Agents↗

PubMed2000

Bone-marrow micrometastases in patients with brain metastases from epithelial cell tumours.

Carcinoma that has metastasized to the central nervous system (CNS) poses a particular clinical problem regarding confirmation of the diagnosis and subsequent management. Prior to excision, thorough evaluation for coexisting systemic disease is essential, but current imaging techniques are limited by their spatial resolution and under-stage many patients. We evaluated the potential utility of bone-marrow evaluation for micrometastatic cells in patients with CNS metastasis. Bone-marrow aspirates were examined for cytokeratin-positive cells in 12 consecutive patients who presented with symptomatic space-occupying lesions of the CNS. These patients had previously undergone surgical excision of either gastrointestinal or breast cancers. All twelve had micrometastases in their bone marrow at the time of presentation with the CNS disease and all had a fatal outcome within 13 months. In nine of the 12 patients, bone-marrow micrometastases were the only evidence for systemic spread. Three patients had elevated serum tumour markers and two of these had radiologically detectable recurrence elsewhere. Bone-marrow micrometastases indicate concurrent systemic involvement and a poor prognosis. The results suggest that bone-marrow evaluation for systemic spread is a useful diagnostic adjunct and should be performed before considering diagnostic biopsy or excision.

Adenocarcinoma↗

PubMed2000

Bone marrow micrometastases and gastrointestinal cancer detection and significance.

Accurate staging of cancer is important, as the presence or absence of systemic spread determines treatment. The sensitivity of current imaging and biochemical techniques is suboptimal for the detection of minimal residual disease and latent metastases. This results in understaging and potential undertreatment. To improve detection of disseminated epithelial malignancy, immunohistochemical and molecular methods have been employed that search for epithelial cell-specific proteins in nonepithelial tissue. Bone marrow is mesenchymal tissue (that does not normally express epithelial cell components) and represents an accessible window for detection of micrometastatic carcinoma cells. Detection methods for epithelial cell components (cytokeratins, epithelial membrane antigen, carcinoembryonic antigen) include immunohistochemistry, flow cytometry, reverse transcriptase polymerase chain reaction (rt-PCR), and enzyme linked immunoassay (ELISA). Micrometastatic cells in bone marrow are viable, capable of proliferation, resistant to immune attack, and insensitive to s-phase chemotherapeutic agents. Patients with carcinomas of the lung, breast, prostate, or gastrointestinal tract and in whom bone marrow micrometastases are detected have a foreshortened interval to recurrence and impaired survival. Detection of micrometastases deserves serious consideration in treatment protocols, and standardization of methods is now required.

Bone Marrow Neoplasms↗

PubMed2000

The inflammatory response within Dukes' B colorectal cancers: implications for progression of micrometastases and patient survival.

OBJECTIVES: The aim of this study was to determine the relationship between the inflammatory response in primary colorectal carcinomas, patient outcome, and the fate of bone marrow micrometastases. METHODS: The populations studied were a) 155 consecutive patients with Dukes' B colorectal cancer and follow-up for a mean of 5 yr, from the Mercy Hospital, Cork, and b) 260 consecutive patients with rectal carcinoma Dukes' B and follow-up for >10 yr, from St. Mark's Hospital, London. The primary tumor was assessed for the Jass and "Crohn's-like" lymphoid reactions. In 36 consecutive patients, bone marrow aspirates were examined for micrometastases before and > or = 6 months postoperatively. RESULTS: The relationship between prognosis and the inflammatory reactivity in the tumors was similar in both populations. In the Mercy group there were two deaths among 40 patients who had coexistent Jass and Crohn's-like infiltrates. This contrasted with 25 deaths among 58 patients in whom both infiltrates were absent (p < 0.005). Results were intermediate in cases in which either type of inflammatory reaction was present alone. In the St. Mark' s patients similar prognostic differences were sustained for up to 10 yr. Bone marrow micrometastases were present in 12/36 patients preoperatively and in 14/36 postoperatively. Seven of 12 patients with preoperative micrometastases were negative postoperatively, indicating clearance of tumor cells. Nine of 24 who tested negative preoperatively had micrometastases postoperatively. The clearance and presence of postoperative micrometastases was related to the immunological responses in the primary tumor. CONCLUSIONS: These results demonstrate an association between the inflammatory reaction, prognosis, and clearance of micrometastases, indicating a systemic antitumor reaction that confers a survival advantage.

Aged↗

PubMed2000

Comparative survival rates of human-derived probiotic Lactobacillus paracasei and L. salivarius strains during heat treatment and spray drying.

Spray drying of skim milk was evaluated as a means of preserving Lactobacillus paracasei NFBC 338 and Lactobacillus salivarius UCC 118, which are human-derived strains with probiotic potential. Our initial experiments revealed that NFBC 338 is considerably more heat resistant in 20% (wt/vol) skim milk than UCC 118 is; the comparable decimal reduction times were 11.1 and 1.1 min, respectively, at 59 degrees C. An air outlet temperature of 80 to 85 degrees C was optimal for spray drying; these conditions resulted in powders with moisture contents of 4.1 to 4.2% and viable counts of 3.2 x 10(9) CFU/g for NFBC 338 and 5.2 x 10(7) CFU/g for UCC 118. Thus, L. paracasei NFBC 338 survived better than L. salivarius UCC 118 during spray drying; similar results were obtained when we used confocal scanning laser microscopy and LIVE/DEAD BacLight viability staining. In addition, confocal scanning laser microscopy revealed that the probiotic lactobacilli were located primarily in the powder particles. Although both spray-dried cultures appeared to be stressed, as shown by increased sensitivity to NaCl, bacteriocin production by UCC 118 was not affected by the process, nor was the activity of the bacteriocin peptide. The level of survival of NFBC 338 remained constant at approximately 1 x 10(9) CFU/g during 2 months of powder storage at 4 degrees C, while a decline in the level of survival of approximately 1 log (from 7.2 x 10(7) to 9.5 x 10(6) CFU/g) was observed for UCC 118 stored under the same conditions. However, survival of both Lactobacillus strains during powder storage was inversely related to the storage temperature. Our data demonstrate that spray drying may be a cost-effective way to produce large quantities of some probiotic cultures.

Bacteriocins↗

PubMed2000

Differential expression of neurokinin-1 receptor by human mucosal and peripheral lymphoid cells.

Substance P (SP) has been implicated in peripheral and mucosal neuroimmunoregulation. However, confusion remains regarding immunocyte expression of the receptor for SP, neurokinin-1 receptor (NK-1R), and whether there is differential NK-1R expression in the mucosal versus the peripheral immune system. In the same assay systems, we examined the expression of NK-1R in human lamina propria mononuclear cells (LPMC), peripheral blood mononuclear cells (PBMC), peripheral blood lymphocytes (PBL), monocytes, and monocyte-derived macrophages (MDM). Using standard reverse transcription (RT)-PCR, mRNA expression of both the long and the short isoforms of the NK-1R was evident in LPMC but not in PBMC, PBL, monocytes, or MDM. However, by using nested RT-PCR NK-1R mRNA expression was detected in PBMC, PBL, monocytes, and MDM. This level of expression was found to represent one NK-1R mRNA transcript in >1,000 cells. In contrast, by using competitive RT-PCR we demonstrate that LPMC express a more biologically significant level of eight NK-1R mRNA transcripts per cell. Flow cytometric detection of NK-1R expression at the protein level was evident in LPMC but not in PBMC. These findings illustrate the extreme sensitivity of nested RT-PCR and the advantages of competitive RT-PCR in comparative studies of receptor expression in different cell populations. This study suggests that, under normal conditions, readily detectable expression of NK-1R in human mononuclear cells occurs at the mucosal level rather than in the peripheral circulation.

Adenocarcinoma↗

PubMed2000

Neurokinin-1 receptor expression in inflammatory bowel disease: molecular quantitation and localisation.

BACKGROUND: Substantial evidence implicates the neuropeptide substance P (SP) in mucosal immunoinflammatory responses. Autoradiographic studies have suggested a disturbance in SP receptor expression in inflammatory bowel disease (IBD). AIMS: Because of technical limitations such as poor cellular resolution with autoradiography, we used molecular methods to specifically localise the cellular expression of the neurokinin-1 receptor (NK-1R) in IBD colon, and to quantitate NK-1R mRNA expression levels therein. METHODS: In situ hybridisation and immunohistochemistry were used to localise NK-1R mRNA and protein, respectively, in normal, ulcerative colitis (UC), and Crohn's disease (CD) colonic resections. NK-1R mRNA expression levels of normal, UC, and CD mucosal biopsies were quantitated by competitive reverse transcription-polymerase chain reaction. RESULTS: NK-1R expression was localised to lamina propria mononuclear cells, epithelium, submucosal vasculature, smooth muscle, and myenteric plexus of normal and IBD colon. No ectopic NK-1R expression was observed in IBD. However, we found increased numbers of NK-1R expressing lymphoid cells in IBD tissue, aberrant negative epithelial expression of NK-1R in UC, and increased expression of NK-1R in CD myenteric plexus. Quantitation of NK-1R mRNA expression in IBD colonic mucosal biopsies revealed marked upregulation of NK-1R mRNA levels compared with non-inflamed mucosal expression levels (p<0.01). CONCLUSIONS: This report demonstrates the strategic localisation and upregulation of NK-1R expression in IBD colon, and thereby suggests the involvement of substance P in the pathophysiological symptoms of IBD.

Adult↗

PubMed2000

Malignant catarrhal fever: polymerase chain reaction survey for ovine herpesvirus 2 and other persistent herpesvirus and retrovirus infections of dairy cattle and bison.

Using a polymerase chain reaction (PCR) test for sequences of ovine herpesvirus 2 (OHV2), this virus was shown to be significantly associated with sheep-associated malignant catarrhal fever (SA-MCF) in terminal cases of disease in 34 cattle and 53 bison. Ovine herpesvirus 2 was not detected in cattle (38) and bison (10) that succumbed to other diseases. Other persistent herpesviruses, retroviruses, and pestivirus, some of which have been previously isolated from cases of SA-MCF, were not associated with the disease. These included bovine herpesvirus 4 (BHV4), bovine lymphotrophic herpesvirus (BLHV), bovine syncytial virus (BSV, also known as bovine spumavirus), bovine immunodeficiency virus (BIV), and bovine viral diarrhea virus (BVDV). A PCR survey for OHV2 in DNA from individual cow's peripheral blood lymphocytes in 4 dairies showed that the 1 dairy that was in close contact to sheep had a prevalence of OHV2 of 21.3%, whereas the 3 other dairies had no OHV2. Prevalence of the other herpesviruses and retroviruses in the dairy cows was variable, ranging from 2% to 51% for BHV4, 52% to 78.7% for BLHV, and 10% to 34% for BSV. Bovine lymphotrophic herpesvirus and BSV were also found in a few (1-4 of 21 tested) cases of terminal SA-MCF, but BIV and BVDV were not found in either the dairy cows sampled, or in the cases of SA-MCE No significant correlation was found between the presence of any 2 viruses (OHV2, BHV4, BLHV, BSV) in the dairy cows or terminal cases of SA-MCE

Animals↗

PubMed2000

Epizootic malignant catarrhal fever in three bison herds: differences from cattle and association with ovine herpesvirus-2.

Three bison herds in Colorado experienced high mortality from malignant catarrhal fever (MCF). In comparison with cattle, the bison had a more rapidly progressive disease, fewer clinical signs, and milder inflammatory histologic lesions. There was consistent association with ovine herpesvirus-2 (OHV-2). Contact with sheep was not consistent. Of 17 animals in herd A, 15 died of acute MCF; 1 was slaughtered while healthy; and 1 developed clinical signs of MCF, was treated with corticosteroids and antibiotics, and died of fungal abomasitis and rhinitis after 5 months. In herds B and C, approximately 300 of 900 and 18 of 20 died of MCF following brief clinical disease. The nearest sheep were 1 mile away from herd A, but direct contact with sheep could be documented in herds B and C. Complete gross and histologic examinations were conducted on 34 animals, including all animals in herd A, and MCF was diagnosed in 31. In addition, field necropsies were performed on all dead animals in herd B and most in herd C and MCF was diagnosed on the basis of the gross lesions in most animals. Clinical signs of each animal in herd A were recorded. Illness was brief, usually 8-48 hours. Clinical signs were subtle; separation from the herd was often observed. In all 3 herds, hemorrhagic cystitis and multifocal ulceration of the alimentary tract were consistently found at necropsy. Mild lymphocytic vasculitis was present in multiple organs. Ovine herpesvirus-2 was found by polymerase chain reaction (PCR) in 71 of 105 formalin-fixed tissue specimens from 29 of 31 animals with MCF. In herd A, blood samples from 13 animals were collected at 5 time points and tested by PCR for the presence of OHV-2 viral sequences in peripheral blood leukocytes. Nine bison with a positive PCR test and 4 with negative results prior to clinical illness died of MCF.

Adrenal Cortex Hormones↗

PubMed2000

Bovine viral diarrhea virus in New World camelids.

A virus known to cause multiple problems in cattle, bovine viral diarrhea virus, was isolated from 3 different cases in New World camelids. Virus isolation, immunoperoxidase staining, and fluorescent antibody staining were used to detect the virus. The herds involved were screened for antibody titers to bovine viral diarrhea and virus isolation from the buffy coat. Bovine viral diarrhea virus should be considered as a cause of death in young and old New World camelids.

Animals↗

PubMed2000

Effect of conjugated bile salts on antibiotic susceptibility of bile salt-tolerant Lactobacillus and Bifidobacterium isolates.

Virtually every antibiotic may cause in vivo alterations in the number, level, and composition of the indigenous microbiotae. The degree to which the microbiotae are disturbed depends on many factors. Although bile may augment antibiotic activity, studies on the effect of bile on the antibiotic susceptibility of indigenous and exogenous probiotic microorganisms are lacking. It was against this background that the antibiotic susceptibility of 37 bile salt-tolerant Lactobacillus and 11 Bifidobacterium isolates from human and other sources was determined in the presence of 0.5% wt/wt oxgall (conjugated bile salts). Oxgall did not affect the intrinsic resistance of lactobacilli to metronidazole (5 microg), vancomycin (30 microg), and cotrimoxazole (25 microg), whereas it resulted in a complete loss of resistance to polymyxin B (300 microg) and the aminoglycosides gentamicin (10 microg), kanamycin (30 microg), and streptomycin (10 microg) for most strains studied (P < 0.001). Oxgall did not affect the intrinsic resistance of bifidobacteria to metronidazole and vancomycin, whereas polymyxin B and co-trimoxazole resistance was diminished (P < 0.05) and aminoglycoside resistance was lost (P < 0.001). Seven lactobacilli, but no bifidobacteria strain, showed unaltered intrinsic antibiotic resistance profiles in the presence of oxgall. Oxgall affected the extrinsic susceptibility of lactobacilli and bifidobacteria to penicillin G (10 microg), ampicillin (10 microg), tetracycline (30 microg), chloramphenicol (30 microg), erythromycin (15 microg), and rifampicin (5 microg) in a source- and strain-dependent manner. Human strain-drug combinations of lactobacilli (P < 0.05) and bifidobacteria (P < 0.01) were more likely to show no change or decreased susceptibility compared with other strain-drug combinations. The antimicrobial activity spectra of polymyxin B and the aminoglycosides should not be considered limited to gram-negative bacteria but extended to include gram-positive genera of the indigenous and transiting microbiotae in the presence of conjugated bile salts. Those lactobacilli (7 of 37) that show unaltered intrinsic and diminished extrinsic antibiotic susceptibility in the presence of oxgall may possess greater upper gastrointestinal tract transit tolerance in the presence of antibiotics.

Anti-Bacterial Agents↗

PubMed1999

Immunogenicity and protective efficacy of a gE, gG and US2 gene-deleted bovine herpesvirus-1 (BHV-1) vaccine.

The efficacy and safety of a gene-deleted bovine herpesvirus-1 (BHV-1) vaccine was determined in a bovine herpesvirus challenge trial in calves. Three different doses of the vaccine were administered intramuscularly at 10(5), 10(6) and 10(7) PFU/ml and compared to a commercial vaccine and non vaccinated control calves. Challenge was performed by intranasal aerosolization with the Cooper strain of BHV-1 (3 x 10(4) PFU/ml). The non-vaccinated calves shed significantly (P < 0.05) more virus than all other groups on days 4, 8 and 10 post challenge. By day 14 post challenge, antibody titers for BHV-1 of calves vaccinated with 10(7) PFU/ml were significantly (P < 0.05) higher than the commercial or non-vaccinated calves. Clinical scores of non-vaccinated calves were significantly (P < 0.05) higher than all other groups on days 4-14 post challenge. With both radioimmunoprecipitation and competitive enzyme-linked immunosorbent assays (C-ELISA), calves in the gene-deleted vaccine groups mounted comparable specific responses against gB, gC and gD post vaccination as calves in the commercial vaccine group, but in a dose dependent manner. These data suggest that the gene-deleted BHV-1 vaccine tested may be used as an effective vaccine in controlling BHV-1 infections.

Administration, Intranasal↗

PubMed1999

Evaluation of serologic and viral detection methods for diagnosing feline herpesvirus-1 infection in cats with acute respiratory tract or chronic ocular disease.

OBJECTIVE: To determine the value of virus isolation (VI), immunofluorescent antibody (IFA) assay, serum neutralization (SN), and ELISA for the diagnosis of clinical feline herpesvirus-1 (FHV-1) infection in cats. ANIMALS: 46 clinically normal cats, 17 cats with signs of acute respiratory tract disease, and 38 cats with signs of chronic ocular disease. PROCEDURE: Conjunctival swabs for VI, conjunctival scrapings for IFA testing, and venous blood samples for SN or ELISA testing were obtained from all cats. RESULTS: FHV-1 was detected in 10.9 and 28.3% of clinically normal cats and in 18.2 and 33.3% of cats with FHV-1-associated disease by VI and the IFA assay, respectively. There were no significant differences in the viral detection rate between cats with acute respiratory tract disease and cats with chronic ocular disease or between diseased cats and clinically normal cats; however, FHV-1 was never detected by both methods in clinically normal cats. Overall FHV-1 seroprevalence was 97% when tested by ELISA and 66% when tested by SN. Seroprevalence did not vary significantly among the 3 groups for either serologic test. Magnitude of SN and ELISA titers varied greatly but independently of presence or absence of clinical signs of FHV-1-associated disease. Sensitivity, specificity, and positive and negative predictive values were assessed for VI and the IFA assay--jointly and individually--and for each SN and ELISA titer magnitude. Values never all exceeded 50%. CLINICAL IMPLICATIONS: Because FHV-1 can be detected commonly in clinically normal cats by the IFA assay or VI, neither test appears to aid in the clinical diagnosis of FHV-1 infection. Seroprevalence does not appear to vary between affected and clinically normal cats. SN, ELISA, VI, and the IFA assay appear to be of limited value in the diagnosis of FHV-1-associated disease in cats. Concurrent assessment of the IFA assay and VI results may permit exclusion of FHV-1 as an etiologic agent if results of both tests are negative.

Acute Disease↗

PubMed1999

Viral load and clinicopathological features of chronic hepatitis C (1b) in a homogeneous patient population.

Monitoring the progression of hepatitis C virus (HCV) includes clinical, biochemical, and histological parameters. Quantitation of viral load by reverse-transcription polymerase chain reaction (RT-PCR) may offer a more reliable marker of disease status. Conflicting reports on viral titers may reflect heterogeneity of patient population, mode of infection, and viral type/subtype. The aim of this study was to correlate quantitative serum viral load with alanine transaminase (ALT) and histological status in a homogenous population. The study population consisted of 77 Rhesus-negative women with chronic hepatitis C type 1b. Homogenous features of this study population included: same defined source of infection (contaminated anti-D immunoglobulin); same duration of disease (17 years at the time of study); same viral type/subtype; same ethnic origin; all healthy child-bearing females at the time of infection; and an absence of competing risk factors for infectious and other liver diseases. None of the patients had received antiviral treatment at the time of study. Liver biopsy was performed on all patients. All biopsies were scored by a single histopathologist who was blinded to the clinical and viral status of each patient. A weak, but statistically significant, correlation (rs =.26; P <.05) between serum viral load and the degree of inflammation (mean value: 3.87 +/- 2.17 [SD]) was found. There was no significant correlation between serum viral load and the degree of fibrosis (mean value: 0.84 +/- 0.8 [SD]; P =.06). There was no significant correlation between serum viral load and ALT, although there was a correlation between ALT and the degree of inflammation (rs =.241; P =.035).

Adult↗

PubMed1999

Micrometastases in esophagogastric cancer: high detection rate in resected rib segments.

BACKGROUND & AIMS: Micrometastases within bone marrow indicate a poor prognosis. We prospectively examined micrometastases in patients undergoing resection of esophagogastric cancers for (1) prevalence in rib marrow; (2) comparative detection rates in rib and iliac crest marrow; (3) responsiveness to neoadjuvant therapy; and (4) viability and tumorigenicity. METHODS: In 50 consecutive patients, marrow was obtained before manipulation of the primary tumor. Micrometastatic cells were detected by staining contaminant cytokeratin-18-positive cells. Viability and tumorigenicity were determined by culture and xenograft. RESULTS: Micrometastases were detected in rib marrow from 88% of patients (44 of 50). When bilateral iliac crest marrow was also obtained, micrometastases were found in 15% (4 of 27) compared with 89% (24 of 27) for ribs (P < 0.001). Detection rates were independent of histological type or nodal status and were similar in patients with and without neoadjuvant therapy. Metastatic cells were cultured from rib marrow of 5 of 7 patients and were tumorigenic in nude mice. CONCLUSIONS: Most patients undergoing resection of esophagogastric malignancies have micrometastases in rib marrow. Detection rates based on iliac crest marrow are underestimates. Hematogenous spread of metastatic cells is independent of histological type or nodal status. The metastatic cells are viable, tumorigenic, and resistant to neoadjuvant therapy.

Adenocarcinoma↗