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J B Hendricks

Publications and source records attributed to J B Hendricks.

27 records · Page 2Linked to original sources
PubMed1993

Comparison of two antibodies for evaluation of estrogen receptors in paraffin-embedded tumors.

Estrogen receptor (ER) content in breast cancer specimens is correlated with a prolonged disease free survival and increased likelihood of response to hormone therapy. Relatively few anti-ER antibodies are currently available for use in formalin-fixed, paraffin-embedded tissue. Recently, a new anti-ER monoclonal antibody (ERID5; AMAC, Westbrook, Maine) was generated which requires antigen retrieval by microwave oven heating for detection in routinely processed tissue. The specific aim of this study was to compare the ERID5 antibody with the commercially available rat monoclonal (ER-ICA; Abbott, Chicago, IL) which requires proteolytic enzyme digestion for detection in paraffin-embedded tissue. Sections from 20 cases of primary breast carcinoma previously assayed by dextran-coated charcoal (DCC) analysis were examined. Quantitation of ER antibody staining was performed without knowledge of the DCC values. Specimens containing > or = 20% specifically stained malignant cells were considered ER positive. The sensitivity and specificity of visual ER-ICA immunostaining were 57% and 83%, respectively. The sensitivity and specificity of visual ERID5 immunostaining were 93% and 50%, respectively. The predictive value of positive staining was 89% for the ER-ICA antibody and 81% for the ERID5 antibody. The predictive value of negative staining was 45% for the ER-ICA antibody and 75% for the ERID5 antibody. Previous studies have demonstrated a linear correlation between DCC values and the positive nuclear area (PNA) generated by image analysis for ER-ICA immunostaining. In the present study, a similar correlation between DCC value and ERID5 percentage PNA was observed (R = 0.670; P < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

A method for detecting variability arising from errors in sample processing of paraffin-embedded tissue for DNA content analysis.

We present a method for controlling variability that may arise from inconsistencies in sample preparation for DNA content analysis of paraffin-embedded tissue. Human tonsil tissue obtained from routine surgical specimens was embedded in paraffin according to standard protocols. Fifty-micrometer sections were cut from the block and analyzed each day for 20 days to establish control ranges. One tonsil tissue section was processed in parallel with each run of clinical specimens. In this context, a run was defined as the simultaneous processing of 50-microns tissue sections for extraction of cell nuclei (dewaxing and rehydrating). If the tonsil G0/G1 peak coefficient of variation (CV) exceeded 2 SDs of the established mean, and optimum instrument performance and staining were verified, all samples prepared with the tonsil control were reprocessed. Instrument performance and staining were assessed by using the appropriate external controls. By using this rejection rule (12s), the frequency of sample reprocessing in our laboratory was approximately 6%. When the run was repeated and the tonsil control CV was within acceptable range, the G0/G1 peak CV of the corresponding clinical specimens improved 25% of the time. Because most investigators are willing to accept higher CVs for paraffin-embedded tissue than for fresh tissue, it is desirable to have a control to detect decreased peak resolution, resulting from errors in sample processing.

Cell Nucleus↗
PubMed1993

Quantitative morphologic assessment of nuclei extracted from paraffin for DNA flow cytometry.

We present a method for quality control of flow cytometric DNA content studies using nuclei extracted from paraffin-embedded tissue. This method is based on a quantitative morphologic assessment of extracted nuclei. Cell nuclei prepared from 22 paraffin-embedded tumors known to contain discrete diploid and aneuploid stemlines were deposited onto poly-L-lysine-coated glass slides. Nuclei were stained with Diff-quic and examined by light microscopy. Two hundred nuclei were counted and classified based on morphologic appearance into tumor and nontumor groups. Classification criteria included differences in nuclear size, nuclear chromatin structure, the degree of nuclear chromatin condensation, and the presence of nucleoli. Excellent agreement was found between two independent observers (R = 0.989) on the classification of nuclei. The relative number of tumor nuclei on the morphologic preparation was compared with the relative number of aneuploid cells in the DNA histogram. Good agreement was observed (R = 0.975) in all but three cases in which the relative number of tumor nuclei was underrepresented by the percentage of aneuploid nuclei in the DNA histogram. In each case, further analysis by image cytometry demonstrated a diploid and aneuploid component of the tumor cell population. This quantitative method of morphologic examination of the preparation ultimately analyzed by flow cytometry offers several distinct advantages, including: (a) identification of peaks in the DNA histogram, (b) assessment for selective loss of cell nuclei in the extraction process, and (c) identification of biologic heterogeneity in tumor populations.

Cell Nucleus↗
PubMed1993

Morphometric analysis of AgNORs in imprints and sections from non-Hodgkin's lymphomas. An approach to standardization.

The argyrophilic nucleolar organizer region (AgNOR) technique was applied to tissue sections and touch imprints from 20 non-Hodgkin's lymphomas (NHL). The mean nuclear area (NA), mean AgNOR area/nucleus (AA) and NOR percentage nuclear area (NPNA) were determined using image analysis. The AgNOR count, NA and AA were significantly higher in touch imprints than tissue sections within tumors of the same histologic grade. However, no significant difference was observed for NPNA between imprints and sections within tumors of the same grade. Both the mean AgNOR number and the NPNA were significantly higher in aggressive NHL (n = 10) than indolent NHL (n = 10), regardless of sampling method. It is suggested that the NPNA is invariant to the sampling technique; NPNA values from touch imprints and tissue sections can be compared directly. Furthermore, because NPNA is calculated independent of AgNOR number, it is less subjective than manual counting.

Cell Nucleus↗
PubMed1986

Transmissibility and abortogenic effect of equine viral arteritis in mares.

A group of 14 pregnant mares was exposed via contact to 4 mares bred to stallions infected with equine viral arteritis virus. There was a demonstrable febrile response in each donor mare and in 12 of the pregnant mares. All 18 mares became seropositive after exposure. Equine viral arteritis virus was isolated from the nasopharynx of 5 pregnant mares, but not from the donor mares. Ten of the pregnant mares aborted, and virus was isolated from fetal specimens or placenta of 8.

Abortion, Veterinary↗
PubMed1979

Epidemiological observations on contagious equine metritis in Kentucky, 1978.

Contagious equine metritis, introduced by importation of 2 comtaminated stallions from France, affected 54 Thoroughbred brood mares during the 1978 breeding season in Kentucky. The infection was diagnosed bacteriologically and by the use of a complement fixation test. Although lateral spread to stallions, and probably to a few mares, occurred through human agency in the breeding sheds of 2 stud farms, control measures instituted early in the epidemic confined the disease to brood mares bred by stallion on only these farms.

Animals↗
PubMed1976

Brucellosis in feral swine.

Some 255 feral hogs were serologically tested for Brucella titers at a location in the lower coastal plain of South Carolina. Eighteen percent were reactors. The organism was cultured from lymph node tissues in one 3+ years old boar and identified as Brucella suis biotype 1. Prevalence of sero-positive animals increased with age. There were no important differences between sexes.

Age Factors↗