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PubMed1985

Regional specular microscopy of endothelial cell loss after intracapsular cataract extraction: a preliminary report.

In a group of 10 patients (12 eyes) undergoing intracapsular cataract extraction, corneal endothelial cell loss was serially investigated by means of regional specular microscopy. Prevoperatively there were no significant regional differences in the endothelial cell density. Two weeks after surgery, the superior endothelium alone showed a significant cell loss (15.6%). Whereas, a definite endothelial cell loss occurred in each region of the cornea one month after surgery. The cell loss was greater in the superior (22.8%) and lower in the inferior (4.7%), respectively, when compared to that seen in the central cornea (9.6%). In each region, cell loss continued 3 months postsoperatively, but no significant cell loss occurred thereafter. These results suggest that the entire endothelial cell population may participate in the healing of the damage associated with intracapsular cataract extraction and that regional specular microscopy can be of help for detailed evaluation of such a damage.

Aged↗
PubMedDate not supplied

[Study of Magnolia grandiflora extracts in guinea pigs cardiac muscle].

Several extracts from diverse Magnolia grandiflora varieties were pharmacological evaluated in the cardiac muscle. From March to July, flowers and leaves from Magnolia grandiflora, native from the National Institute of Cardiology "Ignacio Chávez", from north, west, and orient zones from Mexico City, and from Puebla, Colima and Chiapas states were collected. They were separately processed and the extracts were obtained by maceration with ethanol-water (1:3 v/v) at 4 degrees C during two weeks. Qualitative analysis was accomplished with thin-layer, column and high-performance liquid chromatographies (HPLC). Functional and molecular analysis was made by specific chemical reactivity and by protonic magnetic resonance (RMN 1H). Pharmacological evaluation was completed in isolated and perfused male guinea pigs hearts. Extracts, fractions, and compounds were administrated by serial bolus in a gradual dose-response curves study in which left intraventricular pressure and coronary perfusion pressure were recorded, evaluating by such the positive inotropic and vasodilator effects of Magnolia grandiflora extracts. Vulgarenol and 2-p-hydroxyphenyl-2-hydroxy-ethylamine were isolated and identified, and the obtained results suggest that its positive inotropic and vasodilator effects are owed to these substances, being complemented by magnograndiolide and tyramine.

Animals↗
PubMed1992

IgG is bound by antigen-antibody bonds and some IgG and albumin are bound by intermolecular disulfide bonds to cartilage in rheumatoid arthritis and osteoarthritis.

To elucidate the mechanisms for the presence of immunoglobulins and human serum albumin (HSA) in articular cartilage from patients with rheumatoid arthritis (RA) or osteoarthritis (OA), the recovery of these molecules was determined in several elution steps. These steps included serial elutions with a neutral buffer to extract entrapped molecules, elution with 6 M guanidine hydrochloride to extract molecules bound by noncovalent interactions, and digestion of cartilage with bacterial collagenase to release molecules covalently bound to cartilage matrix proteins. Significantly more IgG than HSA was recovered with 6 M guanidine after serial elutions with neutral buffer from the cartilages of patients with both RA and OA, consistent with the binding of IgG by antigen-antibody bonds. Degradation of cartilage with collagenase released additional IgG and HSA. Analysis of the IgG and HSA, recovered with guanidine or with collagenase, using SDS-PAGE and transfer blotting, indicated for the first time the presence of disulfide bonds between these molecules and cartilage matrix molecules.

Antigen-Antibody Reactions↗
PubMed1997

Salmon thyroid-stimulating hormone: isolation, characterization, and development of a radioimmunoassay.

Coho salmon (Oncorhynchus kisutch) thyroid-stimulating hormone (TSH) was isolated by ethanol extraction of pituitary glands from mature coho salmon. Extraction was followed by gel-filtration chromatography on Sephadex G-100 superfine, anion-exchange chromatography on a Whatman DE-52 column, and finally by reverse-phase high-performance liquid chromatography. Fractions were monitored for TSH content by a homologous in vivo bioassay and by immunoblots using anti-human TSH beta-subunit antisera. In vivo treatment of coho salmon parr with coho salmon TSH caused a dose-dependent increase in plasma thyroxine level similar to that induced by bovine TSH. The N-terminal sequence (25 residues) of the salmon TSH beta subunit has 56% sequence identity to that of human TSH beta subunit and is identical to the deduced amino acid sequence of trout TSH beta subunit. The N-terminal sequence (25 residues) of the salmon TSH alpha subunit is identical to gonadotropin alpha-II subunit. Molecular sizes of the alpha and beta subunits are 18,000 and 24,000 daltons, respectively, as estimated by SDS-PAGE. Antiserum generated against salmon TSH, which was preadsorbed with alpha subunit using an alpha-subunit affinity column, detected only salmon TSH beta subunit by immunoblot and specifically stained thyrotropin-producing cells of the pituitary gland. A homologous radioimmunoassay (RIA) was developed using purified salmon TSH standard, iodinated TSH beta subunit, and antiserum generated against salmon TSH. Cross-reactivities of GTH I, GTH II, GTH I beta and GTH II beta subunits, alpha subunit, growth hormone, prolactin, and somatolactin were less than 1%. Displacement curves for serial dilutions of plasma and pituitary extracts of various salmonid species, as well as coho salmon pituitary cell culture medium, were parallel to the coho salmon TSH standards. In contrast, plasma of hypophysectomized juvenile coho salmon and pituitary extracts of Pacific tomcod (Microgadus proximus) did not displace bound radiolabeled salmon TSH. Finally, in vivo injection of juvenile coho salmon with triiodothyronine decreased plasma TSH levels, whereas the goitrogen, methimazole, increased plasma TSH levels. Injection of gonadotropin-releasing hormone agonist did not alter plasma TSH. These data suggest that the RIA is specific for TSH and confirm a negative-feedback relationship between the thyroid hormones and TSH.

Amino Acid Sequence↗
PubMed1986

Radioimmunoassay and characterization of atrial natriuretic peptide in human plasma.

A RIA for alpha-human atrial natriuretic peptide (alpha hANP) in plasma was developed and used to study the immunoreactive components secreted by the heart and circulating in peripheral venous plasma. The assay used [125I]diiodotyrosyl-alpha hANP, purified by high pressure liquid chromatography (HPLC), and a C-terminal-specific antiserum purchased from Peninsula Laboratories. Serial dilution curves of coronary sinus plasma samples were parallel with the standard curve, but significant nonparallelism was found in peripheral plasma samples of low immunoreactivity. When plasma was extracted using C-18 Sep-Pak cartridges, serial dilution curves from both coronary sinus and peripheral plasma samples were parallel to the standard curve. Although values for plasma samples assayed before and after extraction agreed closely (r = 0.99; n = 76), immunoreactive ANP in unextracted plasma was consistently greater (70-79 pmol/liter) than in extracts of plasma, suggesting non-specific interference by a component in plasma when assayed without extraction. Mean plasma immunoreactive ANP in 19 normal subjects consuming a normal salt intake was 14 +/- 1 (+/- SE) pmol/liter. In 5 normal men, increasing dietary sodium intake from 10 to 200 mmol sodium/day was associated with a 2-fold increment in ANP levels, and similar changes accompanied acute sodium loading using iv saline. Elevated values were found in patients with congestive heart failure (mean, 58 pmol/liter; range, 0-200; n = 9), chronic renal failure (mean, 118 pmol/liter; range, 30-290; n = 8), and primary aldosteronism (range, 32-90 pmol/liter; n = 3). HPLC and gel chromatographic analysis of the immunoreactive material found in coronary sinus plasma extracts showed that a large amount of the material eluted in the position of alpha hANP. A smaller quantity of immunoreactive material with a mol wt of about 1600 was also identified. Peripheral venous plasma extracts also contained several immunoreactive components, the largest amount of which corresponded to alpha hANP. The pattern of immunoreactive components in peripheral venous plasma, as identified by both gel chromotography and HPLC, was similar to that in coronary sinus plasma drawn during an active phase of hormone secretion. These findings indicate that the heart secretes alpha hANP or a closely similar peptide which is also present in peripheral venous plasma. Plasma immunoreactive ANP is responsive to sodium loading in normal man and is elevated in patients with hypervolemic disorders.

Adult↗
PubMed1998

Prostate cancer microvessels: a novel method for three-dimensional reconstruction and analysis.

BACKGROUND: Studies of prostate cancer microvessels to date have relied on routine two-dimensional images from histologic tissue sections, and there have been no previous reports of three-dimensional (3D) reconstruction and analysis of prostatic microvessels in benign or malignant specimens. Knowledge about the 3D architecture of microvessels would be useful for determining the utility and limitations of two-dimensional (2D) measures, as well as for determining the usefulness of 3D measures to predict pathologic stage and patient outcome in prostate cancer. However, the ability to study microvessels in 3D must first be demonstrated. METHODS: We developed a novel method to visualize and analyze prostate microvessels in three dimensions from serially-sectioned prostate specimens, including tissue preparation, reconstruction of serial histologic sections into 3D volumes, extraction of vessels from this data set, and calculation of geometric characteristics. Eleven regions of benign and cancer tissue were studied and compared in an effort to validate our methodology. RESULTS: Microvessels and glandular elements from benign and malignant tissue were visualized together in three dimensions. In the 3D visualizations, microvessels associated with cancer were seen to have more arbitrary pathways, increased tortuosity, and a more casual relationship with glandular elements than microvessels associated with benign tissue. A quantitative measure, the volume length density, discriminated between benign tissue and cancer better than simple microvessel density in this exploratory study. CONCLUSIONS: Microvessels in prostate cancer have a more homogeneous distribution and greater tortuosity than those in benign tissue. Volume length density of microvessels shows promise as a 3D marker in prostate cancer.

Adenocarcinoma↗
PubMed1992

Alpha-melanocyte-stimulating hormone (alpha-MSH) in the brain of the African lungfish, Protopterus annectens: immunohistochemical localization and biochemical characterization.

The distribution of alpha-melanocyte-stimulating hormone (alpha-MSH) containing neurons and the molecular forms of alpha-MSH-related peptides exhibit substantial differences in the brains of fish and amphibians. Lungfishes, which share similarities with both fishes and tetrapods, represent a valuable group in which to investigate the neuroanatomical and neurochemical facets of evolution. In the present study, we have localized and characterized alpha-MSH-immunoreactive peptides in the central nervous system of the African lungfish Protopterus annectens. Perikarya exhibiting alpha-MSH-like immunoreactivity were observed in two distinct regions of the hypothalamus: the rostral part of the preoptic nucleus and the caudal part of the hypothalamus. In the caudal hypothalamus most alpha-MSH-immunopositive perikarya were located in both the subependymal and deepest layers of the ventral periventricular region. Scattered alpha-MSH-immunopositive cells were occasionally detected in the dorsal side of the caudal hypothalamus. The alpha-MSH-immunoreactive material localized in the brain was characterized by combining high-performance liquid chromatography (HPLC) analysis and radioimmunological detection. The displacement curves obtained with synthetic alpha-MSH and serial dilutions of brain and pituitary extracts were parallel. HPLC analysis of lungfish hypothalamic extracts showed that the major immunoreactive peak coeluted with synthetic desacetyl alpha-MSH and its sulfoxide derivative. An additional peak coeluted with synthetic sulfoxide alpha-MSH. In contrast, in the pituitary, the predominant form of alpha-MSH-like material coeluted with the N,O-diacetyl alpha-MSH standard. These results provide the first evidence for the presence of alpha-MSH-related peptides in the brain of a lungfish. The distribution of alpha-MSH neuronal systems in the lungfish is very similar to that reported in amphibians, supporting the existence of phylogenetic convergences between these two vertebrate groups.

Animals↗
PubMed1995

Neuropeptide tyrosine in the brain of the African lungfish, Protopterus annectens: immunohistochemical localization and biochemical characterization.

Lungfishes, which share similarities with both fishes and amphibians, represent an interesting group in which to investigate the evolutionary transition from fishes to tetrapods. In the present study, we have investigated the localization and biochemical characteristics of neuropeptide Y (NPY)-immunoreactive material in the central nervous system of the African lungfish, Protopterus annectens. NPY-immunoreactive cell bodies were found in various regions of the brain, most notably in the telencephalon (septal area, ventral striatum, and nucleus accumbens), in the diencephalon (preoptic nucleus, periventricular region of the hypothalamus, and ventral thalamus), and in the tegmentum of the mesencephalon. A strong immunoreaction was also detected in cell bodies of the nervus terminalis. Immunoreactive nerve fibers were particularly abundant in the ventral striatum, the nucleus accumbens, the diagonal band of Broca, the hypothalamus, and the mesencephalic tegmentum. Positive fibers were also seen in the median eminence and in the neural lobe of the pituitary. The NPY-immunoreactive material localized in the brain and pituitary was characterized by combining high-performance liquid chromatography (HPLC) analysis and radioimmunological quantitation. The displacement curves obtained with synthetic porcine and frog NPY and serial dilutions of brain and pituitary extracts were parallel. Reversed-phase HPLC analysis of telencephalon, diencephalon, and pituitary extracts resolved a major NPY-immunoreactive peak that coeluted with frog NPY. The similarity between the distribution of NPY-containing neurons and the biochemical characteristics of the immunoreactive peptide in the brain of lungfish and frog strongly favors a close phylogenetic relationship between dipnoans and amphibians.

Animals↗
PubMed1993

Longitudinal study of hepatitis C viremia in chronic hepatitis C.

Serial serum samples from 20 untreated patients with chronic hepatitis C virus (HCV) infection were tested for HCV RNA by a nested polymerase chain reaction assay using primers from the highly conserved 5' noncoding region to determine the relationship between hepatitis C viremia and the activity of liver disease during the natural course of chronic HCV infection. Semiquantitation of serum HCV RNA level was achieved by testing serial 10-fold dilutions of RNA extracts to determine the end-point titer. All the patients were HCV RNA positive at presentation. There was a poor correlation between the initial HCV RNA titer and serum transaminase levels. All patients except one were persistently HCV RNA positive during a follow-up period of 1.5-15 years, although 17 (85%) had periods of normal or near-normal transaminase levels. There was no correlation between changes in the serum transaminase levels and HCV RNA titer. Patients with chronic HCV infection have persistent viremia despite fluctuations in ALT levels.

Adult↗
PubMed2000

Natriuretic peptide system in the rat lacrimal gland.

The presence and characteristics of the natriuretic peptides and their receptors in the rat exorbital lacrimal gland were investigated. Serial dilution curves of the gland extracts were parallel to the standard curves of synthetic atrial natriuretic peptide (ANP) or C-type natriuretic peptide (CNP). Immunoreactive ANP or CNP in the gland extracts co-eluted with authentic ANP or CNP, and their contents were 4.95 +/- 0.60 and 2.87 +/- 0.53 pg mg(-1)protein (quadruplicate), respectively. By immunohistochemistry, strong immunoreactivities of ANP and CNP were co-localized in the tubules and excretory ducts of the gland, and moderate immunoreactivities were found in the myoepithelial cells and acini. Productions of guanosine 3',5'-cyclic monophosphate by particulate guanylyl cyclase in the gland membranes were stimulated by natriuretic peptides in a dose-dependent manner, and that by CNP was larger than by ANP. Messenger RNAs for ANP, CNP and their receptors were detected by reverse transcription-polymerase chain reaction. These results indicate that natriuretic peptides and their specific receptors are found in the rat lacrimal gland. Therefore, it is suggested that natriuretic peptide system may play physiological roles in the rat lacrimal gland.

Animals↗
PubMed1999

Noninvasive fecal monitoring of glucocorticoids in spotted hyenas, Crocuta crocuta.

The aim of this study was to validate a method for measuring glucocorticoids noninvasively in feces of spotted hyenas (Crocuta crocuta). Three established enzyme immunoassays (EIA) for cortisol, corticosterone, and 11-oxoetiocholanolone were tested, but proved unsatisfactory. A new EIA using another corticosterone antibody was established and was used for all subsequent analyses; this EIA was validated by demonstrating parallelism between serial dilutions of spotted hyena fecal extracts and dilutions of standard corticosterone and by the recovery of corticosterone added to fecal extracts. High-performance liquid chromatography (HPLC) fractions analyzed by EIA showed various immunoreactive substances with polarities of unconjugated steroids. The physiological relevance of fecal glucocorticoid metabolites was further validated by demonstrating that (1) injection of exogenous ACTH to four males and two females led to a significant increase in fecal glucocorticoid metabolites within 24-50 h, (2) the translocation of a male spotted hyena to a new enclosure resulted in a fivefold increase compared to baseline concentrations, and (3) agonistic social interactions and physical conflict resulted in large increases of fecal glucocorticoid metabolites in both protagonists. Fecal steroid assessment is therefore of use in monitoring adrenal activity in spotted hyenas.

Adrenocorticotropic Hormone↗
PubMed1992

Lack of effect of TRH on alpha-MSH release from the neurointermediate lobe of the lizard Lacerta vivipara.

Thyrotropin-releasing hormone (TRH) is a potent stimulator of melanotropin (alpha-MSH) release from pituitary melanotrophs in pig, frog, and fish. Concurrently, it has recently been shown that injection of TRH induces skin darkening in the lizard Anolis carolinensis (Licht and Denver, 1988). In the present study, we have thus investigated in vitro the possible effect of TRH on alpha-MSH release from the lizard (Lacerta vivipara) neurointermediate lobe, by means of the perifusion technique. Using our radioimmunoassay procedure, we found that serial dilutions of L. vivipara NIL extracts and synthetic alpha-MSH gave parallel binding curves. Administration of graded doses of TRH (10(-8)-10(-6) M) did not cause any modification of alpha-MSH release. In contrast, infusion of a depolarizing concentration of K+ induced a robust stimulation of alpha-MSH secretion. These results indicate that, in the lizard L. vivipara, the neuropeptide TRH does not stimulate pituitary melanotrophs.

Animals↗
PubMed1994

Enantioselective high-performance liquid chromatographic method for the determination of methadone in serum using an AGP and a CN column as chiral and analytical column, respectively.

A simple and sensitive HPLC method with ultraviolet absorption detection at 200 nm is described for the determination of methadone enantiomers in human serum, using dextropropoxyphene as an internal standard and organic solvent extraction. Separation was performed on two serially coupled columns, CN and Chiral AGP, with a mobile phase consisting of acetonitrile, dimethylocytlamine and phosphate buffer. Using 1.0 ml of serum, 5 nmol/1 of each enantiomer could be determined with an acceptable precision. No interactions from several drugs were observed. The method has been successfully used in a pharmacokinetic study. More than 2500 serum samples have been separated on the same AGP column with acceptable selectivity and resolution.

Chromatography, High Pressure Liquid↗
PubMed1989

Presence of immunoreactive atrial natriuretic peptide in follicular fluid, ovary and ovarian perfusates.

Immunoreactive atrial natriuretic peptide (ir-ANP) was measured in the follicular fluid of pig ovarian follicle, and rabbit ovarian homogenates and perfusates using a specific radioimmunoassay (RIA). Serial dilution curves made with the extracts of follicular fluid, ovarian homogenates and perfusates using SepPak C18 cartridges were parallel with the RIA standard curve. On gel filtration chromatography and reverse phase HPLC, all extracted materials showed high and low molecular weight forms of ir-ANP. The amount of ir-ANP in rabbit ovary was 40.70 +/- 0.39 pg/mg and that in follicular fluid of pig ovarian follicle was 18.88 +/- 2.49 pg/ml.

Animals↗
PubMed1989

Characterization of an HPV type 11 isolate propagated in human foreskin implants in nude mice.

Human papillomavirus type 11-Hershey (HPV-11-H) from an extract of genital warts has been serially passaged by infecting human foreskin chips that are then implanted in athymic mice (J. W. Kreider, M. K. Howett, A. E. Leure-Dupree, R. J. Zaino, and J. A. Weber (1987), J. Virol. 61, 590). Subsequent attempts to propagate HPVs present in other human lesions have not been successful. In an effort to identify the basis for the seemingly unique ability of HPV-11-H to propagate in the xenografts, we carried out extensive physical and functional characterizations of the cloned DNA, including restriction digestions, DNA sequencing of transcriptional control regions, and E2 trans-activation of the upstream regulatory region. We uncovered no significant differences compared to the prototype HPV-11 (K. Dartmann, E. Schwarz, L. Gissmann, and H. zur Hausen (1986) Virology 151, 124; H. Hirochika, T. R. Broker, and L. T. Chow (1987) J. Virol. 61, 2599). Moreover, viral enhancer assays indicated that the observed stimulatory effect of pregnancy on condylomata and of estradiol on experimental cysts is likely an indirect one and could not be attributed to up-regulation of the HPV-11 transcriptional enhancer.

Animals↗
PubMed1988

Efficacy of continuous treatment with astemizole (Hismanal) and terfenadine (Seldane) in ragweed pollen-induced rhinoconjunctivitis.

Astemizole (Hismanal; Janssen Pharmaceutica Inc., Mississauga, Ontario, Canada) and terfenadine (Seldane; Merrell Dow Pharmaceuticals [Canada], Inc., Concord, Ontario, Canada) were compared for clinical efficacy in a double-blind randomized trial during the ragweed pollen season. Sixty adults, with a history of ragweed-induced rhinoconjunctivitis, were matched according to sensitivity to ragweed pollen. Half took astemizole, 10 mg/day, and the rest took terfenadine, 60 mg twice daily. Medications were started 1 week before and continued daily until 1 week after the ragweed pollen season (7 weeks). If the trial medication was insufficient to keep symptoms well controlled, a steroid nasal spray and/or eye drops were used in the minimum dose that would ensure symptoms were not troublesome. Subjects completed a diary of nocturnal and daytime nasal and eye symptoms and recorded the amount of concomitant medications used. Astemizole showed greater efficacy than terfenadine in controlling rhinorrhea; in addition, the astemizole group used less nasal spray. Other nasal symptoms, eye symptoms, and use of eye drops were similar in the two groups. Skin test sensitivity to serial dilutions of histamine and ragweed extract was determined 1 and 7 weeks after the start of the trial medication. More tachyphylaxis to histamine was shown by the subjects taking terfenadine, as demonstrated by a larger increase in skin sensitivity over the study period. However, a similar change was not observed for ragweed skin sensitivity. These results suggest that when the medication is started before and continued daily throughout the pollen season, astemizole is more efficacious than terfenadine in controlling nasal symptoms, but there is little difference for eye symptoms.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Presence and release of immunoreactive atrial natriuretic peptide in granulosa cells of the pig ovarian follicle.

Atrial natriuretic peptide (ANP) has been reported to be locally synthesized in the ovary although its physiological roles are still unknown. To define the origin of ovarian ANP, we demonstrated the presence and release of immunoreactive (ir) ANP in pig granulosa cells and characterized its biochemical properties. Serial dilution curves made with the extracts of pig granulosa cells, their perfusates and follicular fluid were paralleled to the standard curve of ANP. The amount of irANP in the granulosa cell was 2 fg/cell. The total amount of irANP in granulosa cells significantly correlated with the levels of irANP in follicular fluid. Additionally, the total content of irANP in the follicle negatively correlated with the follicular size. On reverse phase HPLC, the major form of irANP in granulosa cells and follicular fluid was high molecular weight but that in perfusate was low molecular weight. In Northern blot analysis, ANP mRNA was detected in the pig granulosa cells. Immunohistochemistry showed ANP prohormone location in granulosa cells of rat ovary. These data strongly suggest that the granulosa cells synthesize and secrete ANP.

Animals↗
PubMed1995

Development of a PCR amplification assay as a screening test using bulk milk samples for identifying dairy herds infected with bovine viral diarrhea virus.

The approach of cDNA synthesis followed by polymerase chain reaction (PCR) amplification was used to develop a rapid screening test for the detection of bovine viral diarrhea virus (BVDV) in bulk tank milk samples. The initial development of this detection method was done using lactating Holstein cows; 1 acutely infected with BVDV following experimental inoculation and 2 persistently infected (PI) with BVDV. Viral RNA was extracted from somatic cells purified from whole milk using a guanidinium isothiocyanate and phenol/chloroform extraction method. Oligonucleotide primers were selected from the 5'untranslated region (5'UTR) and p80 region of BVDV genome. In the acutely infected cow, BVDV RNA was identified from days 6 to 10 postinoculation. Viral RNA extracted from somatic cells of milk from PI cows was detected by PCR using both 5'UTR and p80 primer sets. The sensitivity of PCR detection was determined by preparing dilutions of whole milk obtained from the BVDV persistently infected animals with milk from a BVDV-negative cow followed by purification of somatic cells and RNA extraction. BVDV was detected in milk serially diluted to 1:640 using PCR amplification. In addition, PCR amplification was 14.6 times more sensitive than virus isolation in detecting BVDV RNA in purified milk somatic cells. PCR detected BVDV RNA from a minimum of 580 somatic cells while the detection limit of virus isolation was 8500 cells. The sensitivity and specificity of BVDV amplification were confirmed by Southern hybridization analysis. BVDV RNA was detected using PCR in 33 out of 136 bulk milk samples collected from 124 individual herds using the 5'UTR primer set. These results indicate that PCR analysis of bulk tank milk samples may provide a rapid and sensitive method of screening herds for the presence of BVDV infections.

Animals↗