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Biomedical subjects

J Jones

Publications and source records attributed to J Jones.

At least 379 records · Page 21Linked to original sources
PubMed1995

Secreted ovarian stromal substance inhibits ovarian epithelial cell proliferation.

OBJECTIVE: Determine the effects of factors secreted by normal human ovarian stroma on the proliferation of benign and malignant ovarian epithelia, in vitro. METHODS: Primary cultures of normal human ovarian surface epithelium (HOSE), human ovarian stromal tissue (HOST), and epithelial ovarian carcinomas (CSOC) were established from surgical specimens and characterized immunohistochemically using anti-cytokeratin, vimentin, and Factor VIII antibodies. Stroma-conditioned media (SCM) were collected over 3 days from confluent HOST cultures. The SCM were dialyzed, lyophilized, resuspended, and added to HOSE, CSOC, SKOV-3, and Caov-3 ovarian cancer cell cultures and growth inhibitory effects were assayed by MTS and [3H]thymidine uptake. RESULTS: SCM inhibited the growth and DNA synthesis of normal HOSE cells and cancer cells by 79-99% in > 10-cell lines studied to date. The inhibitory effect was rapid in onset with 31-82% reduction in DNA synthesis at 1 hr and approximately 50% return of activity by 23 hr following a 1-hr SCM pulse treatment. The SCM inhibitory activity was not abolished by boiling or by absorption with heparin-agarose. Size exclusion filtration places the molecular weight of the inhibitory substance between 1 and 3 kDa. Neither trypsin nor proteinase K treatments altered the inhibitory activity of SCM, while a Bligh-Dyer organic extraction placed the activity in the aqueous phase. CONCLUSION: A heat-stable, non-heparin-binding, low-molecular-weight, water-soluble substance secreted by normal ovarian stroma significantly inhibits HOSE and ovarian cancer cell proliferation. Derangements in normal ovarian stroma-epithelial interactions may contribute to growth dysregulation of the surface epithelia and result in ovarian carcinogenesis.

Biological Factors↗
PubMed1995

The maize transposable element Ac is mobile in the legume Lotus japonicus.

To evaluate the prospects for transposon mutagenesis in the autogamous diploid legume Lotus japonicus, the behaviour of the maize transposable element Ac was analysed in the progeny of 38 independent transgenic plants. The conditions for monitoring donor site excision using histochemical localization of beta-glucuronidase activity or the alternative spectinomycin resistance assay were established, and used to follow Ac mobility through two generations. Somatic excision was monitored as variegated cotyledons in the T2 generation and germinal excision events were scored in segregating T3 families as complete beta-glucuronidase-mediated staining of cotyledons or as a fully green spectinomycin-resistant phenotype. Using these assays an average germinal excision frequency of 12% was estimated in the T3 offspring from variegated plants. The fidelity of the excision assays was ascertained by comparing the frequency of germinal excision to the frequency of Ac reinsertion at new positions of the genome. Transposition of Ac in 42% of the plants and detection of the characteristic Ac insertion/excision footprints suggests that insertion mutagenesis with the autonomous maize Activator element is feasible in Lotus japonicus. Parameters influencing Ac behaviour, such as dosage, position effects and modification of the element itself, were also investigated comparing homozygous and hemizygous plants from the same family and by analysing different transformants.

Base Sequence↗
PubMed1995

Ubiquitous expression and imprinting of Snrpn in the mouse.

Snrpn is known to be abundantly expressed in rodent brain and heart, and in two separate studies with neonatal mouse brain it has been shown to be maternally imprinted, that is, the maternal allele is normally repressed. We now provide evidence on the expression profile and imprinting status of Snrpn throughout development. Using RT-PCR, we have established that Snrpn is further expressed at low levels in lung, liver, spleen, kidney, skeletal muscle, and gonads. Moreover, using mice with only maternal copies of Snrpn (maternal duplication for the chromosome region involved and parthenogenotes), we have shown that the gene is imprinted in all of these tissues and, generally, from the time the gene is first expressed at 7.5 days gestation. In contrast to the findings made with the imprinted genes, Igf2, Ins1, and Ins2, there is no evidence of tissue-specific imprinting in the embryo with Snrpn. Nor, as found with Igf2 and Igf2r, is there evidence of a window of biallelic expression between the germ line imprint and the time of gene repression. The absence of Snrpn expression in early embryos contrasts with the findings in ES cells.

Animals↗
PubMed1995

Steroid hormone effects on the proliferation of human ovarian surface epithelium in vitro.

OBJECTIVE: The histologically bland-appearing epithelium of the human ovary is responsible for approximately 90% of ovarian cancers. Capitalizing on our ability to propagate this tissue in vitro, we have begun to characterize the steroid hormone responsiveness of the human ovarian surface epithelium. STUDY DESIGN: Primary cultures of the human ovarian surface epithelium are characterized as normal epithelium on the basis of morphologic features, normal karyotype, and immunohistochemistry demonstrating AE1/AE3 cytokeratin positivity and factor VIII negativity. Estrogen and progestin receptors were quantitatively analyzed with a standard receptor-ligand binding assay. Cellular proliferation in response to 1 x 10(-7) mol/L 17 beta-estradiol, progesterone, dihydrotestosterone, and dexamethasone were assessed by means of cell counts and a tetrazolium-based colorimetric assay. RESULTS: Scatchard analyses identified 8.8 x 10(3) estrogen receptors per cell in the premenopausal human ovarian surface epithelium cells, whereas the postmenopausal cells were negative for estrogen receptors. A total of 3.2 to 13.0 x 10(3) progestin receptors per cell was identified, with variable progestin receptor expression in the postmenopausal cells. No significant effect on cell growth could be demonstrated as a result of any of the steroid hormones investigated under the study conditions. CONCLUSIONS: Expression of estrogen and progestin receptors in human ovarian surface epithelium cells may be related to menopausal status. Steroid hormones, however, did not influence cell proliferation under these experimental conditions.

Cell Division↗
PubMed1995

The medical and economic impact of laparoscopically assisted vaginal hysterectomy in a large, metropolitan, not-for-profit hospital.

OBJECTIVE: Our purpose was to evaluate the medical and economic impact of of operative laparoscopy on the surgical approach to hysterectomy for benign disease in a large, metropolitan, not-for-profit hospital. STUDY DESIGN: Retrospective analyses were performed on 2563 hysterectomies (without vaginal or bladder repair) for benign disease, performed by 37 gynecologists between January 1991 and December 1993. Disposable laparoscopic instruments and stapling devices were not used at any time during the study period. Electrosurgery and sutures were used for hemostasis. Parameters analyzed included surgical approach (total abdominal hysterectomy, vaginal hysterectomy, laparoscopically assisted vaginal hysterectomy, and failed laparoscopically assisted vaginal hysterectomy), operative time, postoperative diagnosis, operative blood loss, length of stay, complications, uterine weight, and hospital changes. Charges in each of these parameters were analyzed and compared in 6-month increments. RESULTS: During the study period the percent of hysterectomies performed abdominally declined from 65% to 36%. Laparoscopically assisted vaginal hysterectomy increased from 12% to 45%, and vaginal hysterectomy varied from 23% to 19%. Average operative time was 82 minutes (+/- 2 minutes) for total abdominal hysterectomy, 102 minutes (+/- 2.3 minutes) for laparoscopically assisted vaginal hysterectomy, and 63 minutes (+/- 2 minutes) for vaginal hysterectomy. Hospital stay was 68 hours (+/- 1.5 hours) for total abdominal hysterectomy, 44 hours (+/- 1.2 hours) for laparoscopically assisted vaginal hysterectomy, and 43 hours (+/- 4.1 hours) for vaginal hysterectomy. The average hospital charge was $6552 (+/- $108) for total abdominal hysterectomy, $6431 (+/- $100) for laparoscopically assisted vaginal hysterectomy, and $5869 (+/- $116) for vaginal hysterectomy. CONCLUSIONS: Contrary to previously published studies, our study demonstrates (1) laparoscopically assisted vaginal hysterectomy is a cost-effective procedure when performed with reusable instruments, (2) laparoscopically assisted vaginal hysterectomy is a safe procedure, even when performed by a variety of gynecologists with different skill levels, and (3) the number of hysterectomies performed abdominally was decreased by 29% without incurring more complications or reducing the number of vaginal cases.

Blood Loss, Surgical↗
PubMed1995

Placenta accreta encountered during dilation and evacuation in the second trimester.

OBJECTIVE: To assess the frequency of placenta accreta encountered during dilation and evacuation (D&E) in the second trimester. METHODS: Among 16,827 second-trimester D&E procedures performed at our hospitals and clinics, seven cases of placenta accreta, either suspected clinically or proven histologically, were encountered. These cases were analyzed for history of prior cesarean delivery, placenta localization, and histology of hysterectomy specimens. RESULTS: Six of the seven cases suspected clinically were confirmed histologically. All placenta accreta patients had at least one cesarean delivery (mean 1.7), and five had a preoperative sonogram demonstrating some form of placenta previa. The prevalence of clinical placenta accreta encountered during D&Es in the second trimester was 0.04%, the same as that reported for placenta accreta diagnosed clinically in the third trimester. CONCLUSION: Placenta accreta can be a potential complicating factor in the patient undergoing D&E in the second trimester.

Abortion, Induced↗
PubMed1995

Expression of the receptors for the C5a anaphylatoxin, interleukin-8 and FMLP by human astrocytes and microglia.

The expression of chemotactic receptors in the central nervous system is largely unexplored. In this study, we examined human astrocytes and microglia as well as the conditionally immortalized human astrocyte cell line HSC2 for expression of the C5a-anaphylatoxin receptor (C5aR), the interleukin-8 receptor (IL-8R) and the f-Met-Leu-Phe receptor (FMLPR). Using flow cytometry, indirect immunofluorescence and RT-PCR analysis, we demonstrated that astrocytes, microglia and HSC2 cells contain specific RNA and express surface protein for all three chemotactic receptors. These are the first studies to demonstrate definitively the expression of these chemotactic receptors astrocytes and microglia, thereby expanding the types of cells known to express chemotactic receptors. Moreover, these data suggest that these chemotactic receptors may play an important role in mediating the inflammatory response and perhaps other yet undescribed biological phenomena in the central nervous system.

Adult↗
PubMed1995

Current trends in pediatric tracheotomy.

A retrospective analysis was performed on 103 pediatric patients, less than 5 years of age, undergoing tracheotomy at New York Hospital between 1980 and 1990. Charts were reviewed with respect to primary diagnosis, indication for tracheotomy, duration of the tracheotomy, complication rate and mortality rate. Approximately 62% of the tracheotomies were performed in patients less than 12 months of age, with the most common indication being an acquired or congenital airway abnormality. The number of patients receiving tracheotomies for neurological disorders, however, increased more than threefold over the course of this review. Approximately one-third of the patients experienced immediate, early or delayed complications. There was a significant correlation between the complication rate and weight at the time of the tracheotomy as well as the degree of prematurity of the child. Over one half of the infants under 2000 g suffered complications. A mortality rate of 2.9% was noted in our study with mucous plugging of the tracheotomy being the most common etiology of death.

Airway Obstruction↗
PubMed1995

Bedside fluoroscopy to screen for simple extremity trauma in the ED.

Portable fluoroscopy units are commonly used by orthopedic surgeons to assist in fracture reduction and immobilization. The purpose of this study was to determine the diagnostic accuracy of bedside fluoroscopy performed by emergency department (ED) physicians to screen for simple extremity trauma. Eligible adult patients presenting to the ED with isolated injuries to distal extremities were evaluated prospectively over a 6-month study period. ED physicians independently performed fluoroscopy at the bedside, obtained real-time images (frontal, lateral, and oblique), and documented their initial interpretations. Patients then underwent routine diagnostic radiographs of the same areas. Fluoroscopic findings (real-time and photographs) were compared with the radiologists' final report. Ninety-two patients with 108 extremity injuries were enrolled in the study. Fractures were diagnosed fluoroscopically in 26 cases, for a sensitivity of 0.70. Of the 71 standard radiographs without a fracture, the fluoroscopic diagnosis was accurate in 66, for a specificity of 0.93. The overall diagnostic accuracy was 0.85, with a 95% confidence interval of .67 to 1.00. There were 11 false-negative fluoroscopic reports, involving the radius (3), distal tibia (3), metacarpals (2), fifth metatarsal (1), phalanx (1), and cuboid (1). These results suggest that bedside fluoroscopy lacks sufficient sensitivity to screen for simple extremity fractures in the ED.

Adult↗
PubMed1995

A hive of activity: the future of public health.

In consultation with primary and secondary care, public health has a crucial role in improving the health of the population through health promotion, advice on appropriateness and effectiveness of services and communicable disease control. The speciality of public health medicine can only achieve this goal if it is allowed a degree of stability after the numerous organisational changes of the last two decades. The 'beehive model' of public health may offer an organisational structure that is adaptable to further health service change, reflects the rise in multidisciplinary working, guarantees freedom of speech and is sustainable within existing manpower numbers.

Communicable Disease Control↗
PubMed1995

A controlled trial of bicalutamide versus flutamide, each in combination with luteinizing hormone-releasing hormone analogue therapy, in patients with advanced prostate cancer. Casodex Combination Study Group.

OBJECTIVES: To compare the efficacy and safety of bicalutamide and flutamide, each used in combination with luteinizing hormone-releasing analogue (LHRH-A) therapy, in patients with untreated metastatic (Stage D2) prostate cancer. METHODS: Randomized, double-blind (for antiandrogen therapy), multicenter study with a 2 x 2 factorial design. Eight hundred thirteen patients were allocated 1:1 to bicalutamide (50 mg once daily) and flutamide (250 mg three times daily) and 2:1 to goserelin acetate (3.6 mg every 28 days) and leuprolide acetate (7.5 mg every 28 days). RESULTS: With a median duration of follow-up of 49 weeks, time to treatment failure, the primary endpoint, was significantly (P = 0.005) better for the bicalutamide plus LHRH-A group than for the flutamide plus LHRH-A group. Patients in the flutamide plus LHRH-A group were 34% more likely to fail treatment over the given time period, as indicated by the hazard ratio of 0.749 (95% confidence interval, 0.61 to 0.92) for bicalutamide plus LHRH-A to flutamide plus LHRH-A. Results for secondary endpoints (survival, quality of life, and subjective response) were similar between groups. Diarrhea occurred in 24% of patients in the flutamide plus LHRH-A group, compared with 10% of patients in the bicalutamide plus LHRH-A group (P < 0.001). CONCLUSIONS: In patients with metastatic prostate cancer, bicalutamide plus LHRH-A is well tolerated and provides superior efficacy to flutamide plus LHRH-A with respect to time to treatment failure. Assessment of the effects of these regimens on longer term survival requires additional time for follow-up.

Adenocarcinoma↗
PubMed1995

Ethical dilemmas in intensive care--a case history.

The decision either to withdraw or to continue treating a patient, may often be the source of both ethical and moral dilemmas for the health care professionals involved in that decision. Within the context of an intensive care environment these issues become even more significant as the patient's quality of life is determined by another individual. This case study reviews both the ethical principles that are involved in the decision making process, and the measurement of an individual's quality of life. By focusing on two patients in different situations the ethical problems that nurses face in intensive care are highlighted.

Aged↗
PubMed1995

Is there a relationship between the volume of work carried out in intensive care and its outcome?

This paper reports the results of a study of the association between volume of activity and patient outcome in 26 intensive care units in the United Kingdom. Hospital fatality rates showed a statistically significant (p = .016) negative association with volume. However, mean APACHE II scores, as a measure of the severity of case mix, were also negatively associated with volume (p = .021). Thus, one explanation of the lower death rates at higher volumes is that larger units admit less severely ill patients. For patients admitted immediately after surgery, the correlation between severity standardized mortality ratios and volume (while not significant, p < .1) suggests there may be a volume-output effect unexplained by severity.

APACHE↗
PubMed1995

The paternal inheritance of the centrosome, the cell's microtubule-organizing center, in humans, and the implications for infertility.

Successful fertilization in humans, achieved when parental chromosomes intermix at first mitosis, requires centrosome restoration and microtubule-mediated motility. Imaging of inseminated human oocytes reveals that the sperm introduces the centrosome. The centrosome then nucleates the new microtubule assembly to form the sperm aster--a step essential for successful fertilization. Oocytes from some infertile patients failed to complete fertilization because of defects in uniting the sperm and egg nuclei, indicating that failure to properly effect the cytoplasmic motions uniting the nuclei results in human infertility. These discoveries have important implications for infertility diagnosis and managing reproduction.

Centrosome↗
PubMed1995

Changes in the quality of life of people with learning disabilities who moved from hospital to live in community-based homes.

This paper describes a longitudinal study of the change in quality of life experienced by 36 residents of community-based homes after leaving a hospital for people with learning disabilities. The measure used to evaluate quality of life was Living in a Supervised Home: A Questionnaire on Quality of Life (Cragg and Harrison, 1986). The questionnaire was completed before and after the study group left the hospital. The analyses of the scale shows that there has been a considerable improvement in the quality of life of people who have moved from hospital to community-based homes. Specific data are presented from quality of life sub-scales relating to the use of community facilities and contact with other members of the community.

Activities of Daily Living↗
PubMed1995

The glycosylation of red cell autoantibodies affects their functional activity in vitro.

Factors governing the functional activity of red cell autoantibodies are poorly defined. Here we report the presence of qualitative differences in the glycosylation of IgG autoantibodies which affect in vitro interactions with Fc gamma RIII. The following antibodies were affinity-purified by adsorption and elution from normal red cells: IgG eluted from the red cells of 27 haemolysing or non-haemolysing patients, anti-D in sera from 11 pregnant women, and IgG1 and IgG3 human monoclonal anti-D. Monoclonal antibodies with differing levels of agalactosyl IgG were produced by culturing cell lines at high or low cell density. The % IgG with oligosaccharides lacking terminal galactose residues (agalactosyl IgG) of antibodies was designated as low, medium or high according to their reactivity with a monoclonal antibody to terminal N-acetylglucosamine. Fc gamma RIII-mediated functional activity was assessed by measuring the K-cell-mediated lysis of red cells in eluates diluted to achieve comparable levels of red cells sensitization. All eluates containing allo-anti-D were lytic (range 74-100%). In contrast, lysis by autoantibodies varied from 0 to 100%; 11/13 eluates from red cells of haemolysing patients promoted > 5% lysis compared to 2/7 eluates from red cells of non-haemolysing patients (P < 0.02). The ability of autoantibodies to promote K-cell-mediated red cell lysis correlated inversely with their level of agalactosyl IgG (r = -0.56, P < 0.01, n = 23). Further, monoclonal anti-D antibodies with very low levels of agalactosyl IgG were comparatively more lytic than the same antibodies containing more agalactosyl IgG. Analysis of the ratio of kappa:lambda light chains suggested that autoantibodies from 6/19 patients were monoclonal or oligoclonal in nature. The data indicate that IgG red cell autoantibodies from different patients are functionally heterogenous, and that this may be due, at least in part, to qualitative differences in the Fc region glycosylation reflected by differences in the proportion of agalactosyl IgG. This heterogeneity is consistent with the clonally-restricted nature of the autoantibodies in some patients.

Autoantibodies↗