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Biomedical subjects

S J Bennett

Publications and source records attributed to S J Bennett.

At least 37 records · Page 2Linked to original sources
PubMed1992

The effects of lignocaine on human sperm motility.

OBJECTIVE: The purpose of this study was to assess the motility of human sperm incubated with various concentrations of lignocaine. METHODS: Eleven semen samples with a sperm density greater than or equal to 20 x 10(6) ml and progressive motility greater than or equal to 40% were prepared using a swim-up technique. Aliquots from each sample were incubated for 4 hr under capacitating conditions with lignocaine concentrations of 100, 10, 1, and 0.1 microgram/ml and without additional lignocaine as a control. Digital computerized motion analysis was performed on all samples at 1, 2, and 4 hr after the addition of lignocaine. RESULTS: After 2 hr of incubation a significant (P less than 0.05) increase in the percentage of sperm with a curvilinear velocity greater than 100 microns/sec was observed in those samples incubated with 100 micrograms/ml lignocaine. This stimulatory effect was no longer apparent after a further 2 hr of incubation. No other significant changes were identified in any of the motility parameters examined. CONCLUSIONS: No adverse effects on human sperm motility were identified during incubation with low concentrations of lignocaine. A transient stimulatory effect was observed at a lignocaine concentration of 100 micrograms/ml.

Humans↗
PubMed1992

Postmenopausal women. Factors in osteoporosis preventive behaviors.

Osteoporosis is a serious health hazard mainly affecting postmenopausal and elderly women. Osteoporotic fractures are one of the leading causes of morbidity and death in the elderly population. Prevention of further loss of bone mass in postmenopausal women can be achieved if women take estrogen replacement therapy, consume adequate levels of calcium, exercise regularly, and practice healthy lifestyle behaviors. Elderly women need to follow the same strategies as postmenopausal women with more emphasis on prevention of falls.

Aged↗
PubMed1983

Radioimmunodetection of prostatic cancer. In vivo use of radioactive antibodies against prostatic acid phosphatase for diagnosis and detection of prostatic cancer by nuclear imaging.

Radioimmunodetection (RAID) of prostatic cancer is done by injecting 131I-labeled rabbit antibody IgG against prostatic acid phosphatase (PAP) and performing total-body photoscans with a gamma scintillation camera. Of two patients tested, the PAP RAID scintiscans located the primary or recurrent prostatic cancers in both and showed no disease in the lungs of the patient shown subsequently to have lung cancer. The lung tumor nodules showing anti-PAP IgG accretion were assumed to be of prostatic cancer origin, since one of the original tumors removed from this patient's other lung a year earlier stained for PAP by immunohistochemistry. This study showed that PAP RAID can locate primary and metastatic tumors of prostatic origin.

Acid Phosphatase↗
PubMed1983

Carcinoembryonic antigen radioimmunodetection in the evaluation of colorectal cancer and in the detection of occult neoplasms.

Radioimmunodetection of colorectal cancer was evaluated in 51 patients by injecting 131I-labeled goat antibody immunoglobulin G against carcinoembryonic antigen and performing total-body photoscans with a gamma scintillation camera 24 and 48 h later. The scintigrams were then processed by computer to subtract the images of the 99mTc-serum albumin and pertechnetate administered, which reflect background and nontarget radioactivity, from the 131I-antibody scans. The results indicate that radioimmunodetection is a safe and a potentially clinically useful cancer detection method, which in this study demonstrated primary colorectal carcinomas in 10 of 12 (83%) of the patients evaluated preoperatively and between 87% (46 of 53) and 92% (49 of 53) of known metastatic tumor sites. Thus, the method's overall sensitivity (true-positive rate) was 86%-91% on a tumor-site basis. A false-negative rate of between 9% and 14% and a false-positive rate of less than 4% were found. In 11 of the 51 patients evaluated, tumor sites were detected that were not found by other clinical methods of cancer detection. These sites of tumor were then confirmed later, as much as 40 wk after radioimmunodetection was performed. It is concluded that in colorectal cancer patients, the current method of carcinoembryonic antigen radioimmunodetection can (a) contribute to the preoperative clinical staging of the patients, (b) assist in the postoperative evaluation of tumor recurrence or spread, (c) complement other methods used to assess tumor response to therapy, (d) support the indication of a rising carcinoembryonic antigen titer (when other methods cannot detect tumor) for second-look surgery, and (e) confirm the findings of other detection measures that are less tumor-specific.

Aged↗
PubMed1982

Neutron-capture therapy of human cancer: in vitro results on the preparation of boron-labeled antibodies to carcinoembryonic antigen.

Two samples of 2-phenyl-1,2-dicarba-closo-[1-3H]dodecaborane(12) were prepared by treating 1-lithio-2-phenyl-1,2-dicarba-closo-dodecaborane(12) with 3H2O (0.1 and 5.0 Ci/ml, respectively). These tritiated phenylcarborane samples were subsequently converted to corresponding samples of p-[1,2-dicarba-closo-[1-3H]dodecaboran(12)-2-yl]benzenediazonium ion ([3H]DBD) suitable for azo-coupling reactions. Reaction of the two tritiated diazonium ion samples with 2-napthol resulted in the formation of an azo dye (epsilon = 1.98 X 10(4) M-1 cm-1 at 485 nm). Experiments relating absorbance to 3H activity proved the two [3H]DBD sources to have 3.81 X 10(11) and 2.45 X 10(13) cpm of 3H per mol of tritiated carborane substituent. Purified antibodies to carcinoembryonic antigen were coupled to the [3H]DBD and, after extensive dialysis, the average number of carborane moieties per antibody molecule was determined by measuring the 3H activity associated with a known protein concentration. Further examination of these tritiated carborane-labeled antibodies by affinity chromatography proved that boron labeling did not destroy their immunoreactivity. Correlations of azo-coupling conditions (reactant ratios, pH) with immunoreactivity and antibody protein recovery are presented.

Antibodies, Neoplasm↗
PubMed1981

Experimental studies of tumor radioimmunodetection using antibody mixtures against carcinoembryonic antigen (CEA) and colon-specific antigen-p (CSAp).

Experiments with the GW-39 human colonic carcinoma growing in hamsters showed that injection of radioactive antibody to a colorectal-specific, tumor-associated antigen, CSAp, results in better tumor radiolocalization than was seen previously with radioantibodies to carcinoembryonic antigen (CEA). However, a mixture of both radioactive antibodies resulted in potentiation of CEA-tumor radioimmunodetection without affecting CSAp-tumor radiolocalization. Hence, multi-marker antibody mixtures may be the method of choice in cancer radioimmunodetection.

Animals↗
PubMed1981

Experimental radioimmunotherapy of a xenografted human colonic tumor (GW-39) producing carcinoembryonic antigen.

Experiments were undertaken to evaluate the antitumor effects of 131I-labeled goat antibody immunoglobulin G prepared against carcinoembryonic antigen in hamsters bearing the carcinoembryonic antigen-producing GW-39 human colonic carcinoma. At a single injection of 1 mCi 131I and higher, a marked growth inhibition of GW-39 tumors, as well as a considerable increase in the survival time of the tumor-bearing hamsters, could be achieved. At a dose of 1 mCi, the radioactive affinity-purified antibody appeared to be superior to radioactive normal goat immunoglobulin G in influencing tumor growth and survival time, but no significant difference could be seen at the higher dose of 2 mCi given. Radiobiological calculations indicated that the tumors received, at up to 20 days after therapy, 1325 rads for the specific antibody and only 411 rads for the normal immunoglobulin G preparation. These findings encourage the further evaluation of antibodies to tumor markers for isotopic cancer therapy.

Animals↗
PubMed1980

Circulating immune complexes in cancer patients receiving goat radiolocalizing antibodies to carcinoembryonic antigen.

The circulating radioactivity and antibody immunoreactivity in patients with diverse cancers who had received 131I-labeled goat antibodies to carcinoembryonic antigen (CEA) were studied by Sephadex G-200 column chromatography and with solid-phase (SP) immunoadsorbents containing anti-goat immunoglobulin G(IgG), anti-human IgG, anti-CEA, or CEA. Upon gel filtration, more than 80% of the plasma radioactivity was distributed between native IgG and an excluded macromolecular radioactive fraction (Pool I). The native IgG and Pool I radioactive peaks were immunoreactive with the SP anti-goat IgG and SP CEA to the same extent as was the radioantibody prior to injection. The circulating CEA in patients with elevated titers only partially bound the injected radioantibody since less than 50% of the latter chromatographed as Pool I. Up to 50% of the Pool I radioantibody from this group of patients was bound to the SP anti-CEA, whereas it was minimally reactive with the SP anti-human IgG. The clearance of radioantibody was similar between groups having different amounts of Pool I radioantibody, and injection of CEA radioantibody was not accompanied by a decrease in circulating antigen. Patients with lower CEA titers had the majority of the plasma radioactivity chromatographing as Pool I radioantibody which showed elevated binding to the SP anti-human IgG but not the SP anti-CEA. Tumor localization by photoscanning was observed in seven of eight and nine of nine patients who had circulating CEA-radioantibody and anti-immunoglobulin-radioantibody complexes, respectively. Thus, these studies demonstrate that CEA, as well as human antibody reactive with goat IgG, can form immune complexes in patients given injections of CEA radiolocalizing antibody. However, these complexes do not appear to prevent tumor radioimmunodetection.

Animals↗
PubMed1980

Improved protein labeling by stannous tartrate reduction of pertechnetate.

A procedure has been developed whereby small amounts of protein--specifically human serum albumin and immunoglobulin G--can be labeled with Tc-99m. Artifactual problems associated with electrolytic and stannous chloride labeling procedures are virtually eliminated. The procedure is satisfactory for labeling human serum albumin, normal goat immunoglobulin G, and goat anti-carcinoembryonic antigen immunoglobulin G.

Carcinoembryonic Antigen↗
PubMed1980

Radiolabeling of affinity-purified goat anti-carcinoembryonic antigen immunoglobulin G with technetium-99m.

Affinity-purified goat anti-carcinoembryonic antigen immunoglobulin G was labeled with 99mTc, utilizing stannous tartrate as the reducing agent. The radiochemical yield of labeled antibody ranged from 18 to 37% and was inversely proportional to the initial quantity of pertechnetate ion used. Yields up to 60% could be obtained using small amounts of pertechnetate. The 99mTc-labeled anti-carcinoembryonic antigen immunoglobulin G preparations had a specific activity range of 1 to 6 microCi/microgram protein and had 60% or greater immunoreactivity. Human serum albumin and goat immunoglobulin G were used as model systems to evaluate labeling parameters and analytical methods.

Antibodies, Neoplasm↗
PubMed1977

Elution of tumor-directed antibody from kidneys of mammary tumor-bearing mice.

Immunoglobulin-containing eluates, prepared from kidneys of Paris RIII mammary tumor-bearing mice approximately 10 months old, were incubated with frozen sections of mouse mammary tumor and normal lactating mammary gland and examined by immunofluorescence. The eluates diffusely strained the tumor but did not stain the nonneoplastic lactating mammary gland. Mammary tumor and normal lactating mammary gland were both stained by an antiserum to mammary tumor virus (MuMTV). The euglobulin portion of the eluates, when fractionated on a Sephadex G-200 column, yielded an IgG fraction which was shown by immunodiffusion to react with Paris RIII mammary tumor extract and with anti-mouse globulin but not with nonneoplastic mouse tissue extracts. Since the lactating mammary glands of these animals contain MuMTV, the antibody-containing fraction eluted from the kidneys appeared to be tumor directed rather than virus directed.

Animals↗
PubMed1977

Carcinoembryonic antigen: immunohistologic identification in invasive and intraepithelial carcinomas of the lung.

A total of 58 pulmonary lesions from 48 patients were examined for carcinoembryonic antigen (CEA). The three-layer immunoperoxidase procedure for antigen detection was used with a monospecific anti-CEA antiserum. The control serum was the same antiserum with its specificity removed by affinity chromatography. Normal goat serum was also used as a control. Carcinoembryonic antigen was present in the majority of pulmonary adenocarcinomas and generally absent in the squamous cancers. The major exception was in the well-differentiated squamous lesions where CEA was occasionally found in the keratinizing areas. Of special interest was the finding of CEA in all areas of intraepithelial squamous neoplasia studied.

Adenocarcinoma↗
PubMed1976

Electron microscopy and immunofluorescence of glomerular immune complex deposits in cancer patients.

Kidneys of 29 patients without clinical renal disease were studied by electron microscopy for the presence of glomerular basement membrane deposits: those from 11 of 20 patients with cancers of various sites, but only 1 of 9 patients without cancer contained electron-dense subendothelial deposits. The majority of these kidneys gave positive immunofluorescent reactions for immunoglobulin and complement. However, among a number of the cases studied, a lack of correlation between electron microscopic and immunofluorescence findings has yet to be investigated. Although the number of patients in this study is small because of the difficulty in obtaining tissue for electron microscopy, it is postulated that the deposition of immune complexes in the kidney occurs with a high frequency among cancer patients. The kidneys may thus be a valuable source for isolating tumor-associated antigens and corresponding antibodies.

Adolescent↗
PubMed1975

Adenocarcinoma of the small intestine arising in Crohn's disease. Demonstration of a tumor-associated antigen in invasive and intraepithelial components.

A segment of small intestine surgically removed from a man with intestinal obstruction was found to have coexisting regional enteritis and an invasive adenocarcinoma associated with an area of intraepithelial neoplasia. The cells of the adenocarcinoma and the intraepithelial neoplasia contained a tumor-associated surface antigen capable of reacting with an antiserum prepared against a colonic carcinoma. The importance of thorough sampling of specimens of regional enteritis in accurate reporting of the incidence of carcinoma is stressed, as is the use of immunohistologic techniques as an adjunct to the morphologic diagnosis of preinvasive neoplasia.

Adenocarcinoma↗