Biomedical subjects

G Greene

Publications and source records attributed to G Greene.

At least 37 records · Page 2Linked to original sources

PubMed1996

Selection of highly metastatic variants of different human prostatic carcinomas using orthotopic implantation in nude mice.

The purpose of this study was to determine whether the implantation of human prostate cancer cells into the prostates of nude mice and their subsequent growth there can be used to select variants with increasing metastatic potential. PC-3M and LNCaP cells were injected into the prostates of athymic mice. Tumors from the prostate or lymph nodes were harvested, and cells were reinjected into the prostate. This cycle was repeated three to five times to yield cell lines PC-3M-Pro4, PC-3M-LN4, LNCaP-Pro3-5, and LNCaP-LN3-4. Parental and variant cells were injected into the prostates of nude mice. PC-3M-LN4 cells produced enhanced regional lymph node and distant organ metastasis as compared to PC-3M-Pro4 or PC-3M cells. After i.v. or intracardiac inoculation, PC-3M-LN4 cells produced a higher incidence of lung metastasis and bone metastasis, respectively, than PC-3M or PC-3M-Pro4 cells. Subsequent to implantation into the prostate, LNCaP-LN3 cells produced a higher incidence of regional lymph node metastases than LNCaP-Pro5 or LNCaP cells. After intrasplenic implantation, LNCaP-LN3 cells also yielded experimental liver metastases. The metastatic LNCaP-LN3 cells exhibited clonal karyotypic abnormalities, were less sensitive to androgen (in vitro and in vivo), and produced high levels of prostate-specific antigen. Collectively, the data show that the orthotopic implantation of human prostate cancer cell lines in nude mice is a relevant model with which to study the biology of prostate cancer metastasis and to select variant cell lines with enhanced metastatic potential.

Animals↗

PubMed1995

Consumer satisfaction with a rehabilitation mobile outreach program.

Accessibility to rehabilitation services is often difficult for people with disabilities who live in rural areas. This study examined consumer satisfaction with a rehabilitation outreach approach that utilizes a mobile clinic to provide consultation services. The descriptive survey took place in fifteen rural communities in eastern and northeastern Ontario, Canada. Valid postconsultation mail surveys were completed by 143 consecutive patients with mixed diagnoses (or proxy family members) who had been seen during mobile clinic visits to their home communities (85.1% of patients approached). There were 59 men and 84 women, with an average age of 58.7 years. The main outcome measure was a consumer satisfaction scale. A high level of global satisfaction was reported, with 97.2% of respondents reporting a preference for community outreach over the alternative of traveling to an urban rehabilitation center. Enhanced accessibility was considered to be the major advantage of the outreach program, but concerns about the continuity of care were also expressed. Providing interdisciplinary rehabilitation consultation services on an outreach basis is associated with a high level of consumer satisfaction. From a consumer perspective, the outreach approach seems to be a viable way of addressing some of the rehabilitation needs of rural people with disabilities.

Persons with Disabilities↗

PubMed1995

Isolation of the human peroxisome proliferator activated receptor gamma cDNA: expression in hematopoietic cells and chromosomal mapping.

The nuclear receptor superfamily of transcription factors, which includes the retinoic acid receptors and v-erb A, play important roles in the molecular control of hematopoiesis. To identify nuclear receptors expressed in hematopoietic cells, we screened a human bone marrow cDNA library using a degenerate oligonucleotide and isolated a 1.85-kb full-length cDNA encoding a new human member of this superfamily, the peroxisome proliferator activated receptor gamma (hPPAR gamma). Two different hPPAR gamma transcripts were expressed in hematopoietic cells: a 1.85-kb transcript, which corresponds to the full-length mRNA (PPAR gamma 1), and a 0.65-kb transcript (PPAR gamma 2), which cannot encode all of the nuclear receptor functional domains. Normal neutrophils and peripheral blood lymphocytes, as well as circulating leukemic cells from patients with AML, ALL, and CML, express only PPAR gamma 2 on Northern blot analysis. In contrast, only the PPAR gamma 1 transcript was detected in a variety of human leukemia cell lines and in cultured normal primary bone marrow stromal cells. Both transcripts were detected in various fetal and adult nonhematopoietic tissues. We mapped the location of the hPPAR gamma gene to human chromosome 3p25 by somatic cell hybridization and linkage analysis. PPARs have been shown to be activated by peroxisome proliferating agents, long-chain fatty acids and arachidonic acid. Human PPAR gamma, although homologous to the PPAR gamma s of other species, has unique sequence and amino acid differences. Identification of hPPAR gamma will allow further understanding of its role in human cellular leukotriene, prostaglandin, and peroxide degradative or synthetic pathways, as well as its role in lipid metabolism and regulation of adipocyte differentiation.

Adult↗

PubMed1994

Interstitial cystitis. A patient's perspective.

Interstitial cystitis is a debilitating bladder disorder that affects up to 450,000 people in the United States, 90% of whom are women. Confusion in defining and understanding interstitial cystitis has resulted in the failure to diagnose and treat thousands of afflicted patients, committing them to a life of intractable pain. Even with diagnosis, there are no uniformly effective treatments. It is extremely important that these patients have the understanding and support of the medical community, and they should develop a constructive and effective relationship with their physician and other urologic caregivers.

Cystitis↗

PubMed1993

Localization of immunoreactive epidermal growth factor receptor in neonatal and adult rat hippocampus.

The regional and developmental expression of epidermal growth factor (EGF) receptor in rat hippocampus was investigated utilizing immunocytochemical techniques at the light and electron microscopic levels. EGF receptor immunoreactivity in adult hippocampus was compared to that found at postnatal day 7 (P7). While the receptor was observed in P7 hippocampus, immunostaining was more prominent in the adult hippocampus, especially in the pyramidal CA2 field. Ultrastructural analysis of this region revealed that the receptor was localized to the cell bodies of both P7 and adult neurons rather than the axons or dendrites. The expression of EGF receptor in selected regions of the adult brain was verified by Western blotting. These results demonstrate the presence of EGF receptor in rat hippocampus as early as P7, localize the receptor to the pyramidal cell body, and establish the hippocampal formation, particularly CA2, as a major site of EGF receptor expression in rat brain.

Aging↗

PubMed1992

Estrogen receptors in dendrites and axon terminals in the guinea pig hypothalamus.

The ultrastructural localization of steroid hormone receptors has been made possible by the development of immunocytochemical procedures using monoclonal antibodies. Estrogen receptor-immunoreactivity (ER-IR) in the brain is present most abundantly in neuronal nuclei when observed with light microscopy. However, we have also observed ER-IR in the perikarya and cytoplasmic processes of neurons. To determine the organelles with which the cytoplasmic ER-IR is associated, we developed a technique for ultrastructural visualization of ER-IR. Ovariectomized guinea pigs were perfused, brains vibratome-sectioned, and estrogen receptors immunostained by either an immunoperoxidase-diaminobenzidine technique or by an immunogold-streptavidin procedure, each followed by silver intensification. Electron microscopic analysis confirmed distribution of ER-IR throughout cell nuclei, but ER-IR was also observed in proximal and distal dendrites and rough endoplasmic reticulum. Most surprisingly, however, ER-IR was found in many axon terminals containing predominantly round, and in some cases, flattened clear synaptic vesicles. Parallel experiments examining the distribution of progestin receptors confirmed the localization at the same subcellular sites as for estrogen receptors. The results of this experiment corroborate our earlier findings of extranuclear steroid receptor-immunoreactivity in the brain, and they suggest potential nongenomic sites of action for estradiol and progesterone in dendrites and axon terminals.

Animals↗

PubMed1991

A dietary education program for hypercholesterolemic children and their parents.

A parent-child autotutorial dietary education program for 4- to 10-year-old, hypercholesterolemic children and their families was developed and pilot tested. The 10-lesson program, designed for weekly use at home, uses a "talking-book" approach (audiotapes with accompanying picture booklet) for the child. Parents are provided with information on ways to make recommended dietary changes, along with hands-on activities to do with the children. To help match the instructional approach to the wide developmental range within the children's age span, materials are divided into three program levels that use different story characters and concept presentations. During program development, evaluation by two children (and their parents) for each of the program levels guided the design and refinement of the lessons. A pilot test among 22 hypercholesterolemic children (whose treatment was limited to diet modification) revealed that children within the 4- to 10-year age range liked the "talking-book" approach and identified positively with the story characters. Parents indicated that their materials were clear and helpful. Between the baseline and 3-month follow-up visits, the children exhibited a significant increase in knowledge of heart healthy foods, a decrease in total fat consumption that approached significance, and a significant decrease in plasma low-density-lipoprotein cholesterol values.

Adult↗

PubMed1990

Modification, optimization and simplification of the spot ELISA technique for the enumeration of cells secreting anti-hapten antibodies.

We describe here a modification of the spot ELISA assay for the detection and enumeration of antibody-secreting cells. The modification increases sensitivity, convenience and simplicity while optimizing parameters of time, temperature and reagents. Laboratory reagents and 96 well microtiter plates commonly used for the standard ELISA assay are adapted for use in the spot ELISA assay. Special emphasis is placed on the detection of anti-hapten IgM or IgG production by splenocytes in response to stimulation by a range of doses of antigen. In addition, two procedures are described whereby the spot ELISA assay is altered to yield a measurable optical density: (1) the blue precipitate obtained in the spot ELISA assay is dissolved and the optical density of the resultant blue color is measured, and (2) a standard ELISA substrate is substituted for the spot ELISA substrate to yield a colored solution rather than a precipitate. Both of these are shown to correlate with spot numbers and can therefore supplement or substitute for the enumeration of spots (produced by antibody-secreting cells), thus speeding and mechanizing the assay.

Animals↗

PubMed1990

Nutrition care planning: comparison of the skills of dietitians, interns, and students.

A written case study--or patient management problem--was used to examine how the nutrition care planning process is influenced by increasing clinical experience. The sample consisted of 45 students in diet therapy courses, 46 dietetic interns, and 44 experienced clinical or generalist dietitians. The patient management problem tested data gathering, with sections containing information needed to assess nutritional status, and nutrition care planning, in which subjects identified and evaluated problems and selected short- and long-term goals. Performance was scored by comparing subjects' answers with those of five dietetic experts. Dietitians scored highest and students scored lowest on efficiency of data gathering. Dietitians and interns scored higher than students on proficiency of data gathering and nutrition care planning. Overall, dietitians and interns performed better than students. Only in tasks requiring the highest levels of information processing and/or confidence in clinical judgment were differences between dietitians and interns consistently found. These findings demonstrate that basic nutrition care planning skills are acquired during dietetic internships, but advanced skills are added with clinical experience.

Dietary Services↗

PubMed1989

The immunogenicity of soluble haptenated polymers is determined by molecular mass and hapten valence.

T cell-independent Ag are believed to stimulate antibody formation in the relative absence of Ag processing and T cell help. Previous studies on the type 2 T cell independent (TI-2) Ag DNP-polyacrylamide, have shown that when one systematically varies the molecular mass and hapten valence, the immunogenic potential of this type of molecule depends on definable molecular characteristics. It was found that to be immunogenic, these molecules had to exceed a threshold molecular mass of 100,000 Da and a threshold hapten valence of 20. The present study was undertaken to determine whether such findings could be generalized to other molecules belonging to the TI-2 class of Ag. The molecular characteristics of five chemically different fluoresceinated (FL)-polymers were systematically varied, and their ability to stimulate an IgM antihapten immune response was measured. The polymers used as carriers were carefully size-fractionated and consisted of one natural polymer (dextran), one modified natural polymer (carboxymethyl cellulose), and three synthetic polymers (Ficoll, polyvinyl alcohol, and polyacrylamide). The carriers varied in physical structure from the highly cross-linked Ficoll, to the somewhat branched dextran, to the linear polyacrylamide, carboxymethyl cellulose, and polyvinyl alcohol. Polymers were haptenated with FL and size-fractionated so as to yield a panel of molecules with varying molecular mass, hapten valence, and hapten density. Anti-FL IgM response to these haptenated polymers was measured in vivo after i.p. injection of the FL-polymer in saline, and measured in vitro after culture with unfractionated spleen cells from naive mice. In agreement with the previous studies on DNP-polyacrylamide, it was found that to be immunogenic, each of the FL-polymers had to exceed a comparable threshold value of molecular mass and of hapten valence. Optimal immunogenicity occurred when the FL-polymers had values of mass and hapten density lying within a predictable range. Immunogenicity decreased when these optimal parameters were substantially increased or decreased. We conclude that the immunogenicity of soluble haptenated polymers depends on predictable physical molecular characteristics, and is relatively independent of the chemical composition and conformation of the carrier polymer.

Animals↗

PubMed1986

Cloning of the human oestrogen receptor cDNA.

Poly A+ RNA isolated from the human breast cancer cell line MCF-7 was fractionated by sucrose gradient centrifugation and those fractions enriched in oestrogen receptor (ER) mRNA were used to prepare randomly primed cDNA libraries in the lambda gt11 vectors. Clones corresponding to the ER were isolated from both libraries after screening with either ER monoclonal antibodies (lambda gt11) or synthetic oligonucleotide probes designed from two peptide sequences of purified ER (lambda gt10). Five cDNA clones were isolated by antibody screening and five after screening with synthetic oligonucleotides. The two largest ER cDNA clones, lambda OR3 (1.3 kbase) and lambda OR8 (2.1 kbase), isolated using antibodies and oligonucleotides, respectively, were able to enrich selectively for ER mRNA by hybrid-selection. Furthermore, lambda OR8 contains DNA sequences which cross-hybridize with each of the other ER cDNA clones. These results demonstrate that the clones isolated correspond to the ER mRNA sequence. Using lambda OR8 as a hybridization probe revealed a single poly A+ RNA band of approx. 6.2 kbase in the ER containing human breast cancer cell lines MCF-7 and T47D. In contrast, no hybridization was seen in the human ER-cell line HeLa. The same probe hybridizes to a chicken gene which is expressed in oviduct tissue as a 7.5 kbase poly A+ RNA.

Animals↗

PubMed1986

Infective endocarditis following cardiac catheterization in infancy. A case report and review.

A 4.5-month-old infant with transposition of great vessels and large ventricular septal defect developed acute infective endocarditis following cardiac catheterization. Beta-hemolytic streptococcus was recovered from three blood cultures. The infant survived after 6 weeks intravenous antibiotic therapy. The occurrence of infective endocarditis following cardiac catheterization during infancy is briefly reviewed and discussed. The importance of distinguishing febrile episodes of infancy from infective endocarditis and the use of two-dimensional echocardiography for diagnosis is re-emphasized.

Cardiac Catheterization↗

PubMed1985

Cloning of the human estrogen receptor cDNA.

Poly(A)+ RNA isolated from the human breast cancer cell line MCF-7 was fractionated by sucrose gradient centrifugation and fractions enriched in estrogen receptor (ER) mRNA were used to prepare randomly primed cDNA libraries in the lambda gt10 and lambda gt11 vectors. Clones corresponding to ER sequence were isolated from both libraries after screening with either ER monoclonal antibodies (lambda gt11) or synthetic oligonucleotide probes designed from two peptide sequences of purified ER (lambda gt10). Five cDNA clones were isolated by antibody screening and five were isolated after screening with synthetic oligonucleotides. The two largest ER cDNA clones, lambda OR3 (1.3 kilobase pairs) and lambda OR8 (2.1 kilobase pairs), isolated by using antibodies and oligonucleotides, respectively, were able to enrich selectively for ER mRNA by hybrid-selection. Furthermore, lambda OR8 contains the DNA sequence expected from the two ER peptides and crosshybridizes with each of the other ER cDNA clones. These results demonstrate that the clones isolated correspond to the ER mRNA sequence. Use of lambda OR8 as a hybridization probe revealed a single poly(A)+ RNA band of approximately equal to 6.2 kilobase pairs in the ER-containing human breast cancer cell lines MCF-7 and T47D. In contrast, no hybridization was seen in the human ER-negative cell line HeLa. The same probe hybridizes to a chicken gene that is expressed in oviduct tissue as a 7.5-kilobase-pair poly(A)+ RNA.

Animals↗

PubMed1985

Family practice social work: a new area of specialization.

Many physical problems presented to family physicians by their patients often involve psychosocial variables with stress being a major one. Though family medicine advocates a biopsychosocial focus, one that is compatible with social work, the psychosocial aspects of health are often ignored. The involvement of social workers in the private practices of family physicians to deal with such problems is discussed in this paper as a new area of specialization. Issues such as the medicine-social work gap and the financing of social work services in private family medical practice are also addressed. It is concluded that this should be considered a new area of specialization. However, social workers must take the initiative in its development.

Behavioral Medicine↗

PubMed1984

Recognition of two forms of the estrogen receptor in the guinea-pig uterus at different stages of development by a monoclonal antibody to the human estrogen receptor. Dynamics of the translocation of these two forms to the nucleus.

Two forms of the estrogen receptor were recognised in the cytosol fraction of fetal uterus of guinea pig by a monoclonal antibody (D547Sp gamma) to the human estrogen receptor. It was observed that 60-65% of the total cytosol estrogen receptor (the alpha form) was bound to the antibody, increasing its sedimentation coefficient in a high ionic strength sucrose gradient (10-30% w/v sucrose, 0.4 M KCl) from 4.5 S to 7.4 S. The remaining fraction (the beta form) has the classical sedimentation coefficient of 4.5 S. Dynamic studies of the translocation in vitro of the cytosol receptor to the nucleus as a function of time have shown that the alpha form decreases sharply while the beta form is slightly affected when the cytosol was incubated with the nuclei. In contrast only one form, which is bound totally to the antibody, was found in the nuclear fraction. In addition, the presence of these two forms of the cytosol estrogen receptor was also demonstrated in newborn and immature animals.

Animals↗

PubMed1984

Early adolescent pregnancy: a comparative study of pregnancy outcome in young adolescents and mature women.

Thirty-two adolescents were matched to mature controls for a study of variables known to influence the course and outcome of pregnancy. These included: ethnicity; clinic payment status; year of delivery; parity; and presence or absence of alcohol and tobacco use. The comparative factors examined included: age of menarche; gynecologic age; admission hemoglobin; prepregnant weight and height; weight gain during pregnancy; complications of pregnancy; length of gestation; birth weight; 1- and 5-minute apgar scores; and the presence or absence of congenital defects. There was no significant difference between young adolescents and matched controls in infant birth weight or apgar scores when the above confounding factors were controlled. Young gravidae, however, had significantly shorter gestations, earlier menarche, lower hemoglobin levels, and poorer weight gain during pregnancy than mature women. Multiple-regression analysis suggests that 1) pregnancy weight gain was associated with the trimester the gravida enrolled in the Supplemental Food Program for Women, Infants, and Children (WIC) (p = 0.008) and maternal stature (p = 0.012); 2) length of gestation was associated with maternal stature (p = 0.022) and prepregnant weight (p = 0.011); and 3) maternal hemoglobin was associated with birth weight (p = 0.087). Alternative interpretations are discussed.

Adolescent↗

PubMed1984

Parental behavior and the availability of foods among undernourished inner-city children.

This study was designed to identify differences in parental behaviors and the availability of food between undernourished and well-nourished inner-city children of early school age. Children with a constellation of measurements of height below the 25th percentile, midarm muscle circumference below the 50th percentile, and hemoglobin concentration below 11.5 g/dL were considered undernourished. These children were matched with controls having measurements above these levels. The homes of all children were investigated. Families of undernourished children were found to have significantly less variety of nutritious foods requiring preparation by an adult available in the home (P less than .01), to have greater variety of convenience foods of low nutritional value (P less than .01), and to prefer fewer vegetables (P less than .04) and dairy products (P less than .01). The Polansky Child Level of Living Scale showed that mothers of undernourished children were less likely to prepare meals regularly for their children (P less than .05) and that they were less effective in providing general parental support to their children (P less than .03).

Adult↗

PubMed1983

Characteristics of different cytoplasmic and nuclear estrogen receptors appearing with continuous hormonal exposure.

Biochemical properties of cytosol estrogen receptor (ERC) and nuclear estrogen receptor (ERN) from rat uteri continuously exposed in vivo to 17 beta-[2,4,6,7-3H] estradiol ( [3H]E2) for 6 h have been studied on the basis of immunological recognition and chromatographic elution patterns. Overall concentrations of ERC and ERN did not change during this time period when receptor-saturating concentrations of [3H]E2 were maintained (Jakesz, R., Kasid, A., and Lippman, M. E. (1983) J. Biol. Chem. 258, 11798-11806); however, biochemical characteristics were different in ERC and ERN after short or long term hormonal exposure. When ERC from rats treated with estradiol for 30 min was applied to HAP or DEAE columns, two different ER binding components were seen. DNA binding in a cell-free system revealed that these binding components represented an activated and a nonactivated ERC population. After long term hormonal exposure (6 h), only one component of ERC with low DNA binding could be shown despite the preservation of an equivalent quantity of cytoplasmic binding activity. This binder does not react with a monoclonal antibody directed against extranuclear estrogen receptor species. These data suggest disappearance of the activated ERC population, with appearance of a new, immunologically nonrecognizable ERC species with 6 h of continuous hormonal exposure. Elution profiles of ERN on HAP chromatography reveal 2 different binding components at 30 min and at 6 h of continuous [3H]E2 exposure. There is an increase of the population eluted at higher molarity after 6 h of in vivo treatment. This later eluting binding component is the major DNA binder in vitro. ERN from both time points are recognized immunologically by monoclonal antibody. After reaction with the antibody, the sedimentation coefficient shifted to 8-9 S on sucrose gradients, but the previously described faster sedimentation of ERN extracted 6 h after injection persisted. We conclude that ER in both cellular compartments undergoes time-dependent alterations, which may be involved in the initiation of hormone action.

Animals↗