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1.
Lonnie Embleton Juddy Wachira Allan Kamanda Violet Naanyu David Ayuku 《Culture, health & sexuality》2016,18(3):337-348
Street-connected youth in Kenya are a population potentially at risk of HIV transmission, yet little is known about their perceptions and experiences of sexually transmitted infections (STIs), despite their living in an HIV endemic region. We sought to elucidate the language and sociocultural factors rooted in street life that impact on street-connected young people’s knowledge of and perceptions about the prevention and transmission of STIs, and their diagnosis and treatment, using qualitative methods in western Kenya. We conducted a total of 25 in-depth interviews and 5 focus-group discussions with 65 participants aged 11–24 years in Eldoret, Kenya. Thematic analysis was conducted and data were coded according to themes and patterns emergent until saturation was reached. In general, street-connected young people knew of STIs and some of the common symptoms associated with these infections. However, there were many misconceptions regarding transmission and prevention. Gender inequities were prominent, as the majority of men described women as individuals who spread STIs due to unhygienic practices, urination and multiple partners. Due to misconceptions, gender inequity and lack of access to youth-friendly healthcare there is an urgent need for community-based organisations and healthcare facilities to introduce or augment their adolescent sexual and reproductive health programmes for vulnerable young people. 相似文献
2.
Dinesh Rakheja Payal Kapur Mai P. Hoang Lonnie C. Roy Michael J. Bennett 《Medical hypotheses》2005,65(6):681
Mammalian fatty acid synthase (FASE) overexpression has been shown in a number of human malignancies including colonic adenocarcinoma. Since FASE synthesizes only saturated fatty acids, we hypothesized that cancer cells have a greater proportion of long-chain saturated fatty acids. We studied and found an unequivocal increase in saturated C18 fatty acid (stearic acid) in colonic adenocarcinoma compared to adjacent normal colonic mucosa. The increase is even more striking when measured as a ratio of stearic acid to the unsaturated C18 fatty acids (oleic acid and linoleic acid). This change in fatty acid composition of the cancer cells should significantly alter their physical and biological properties. The increase in relative proportion of saturated fatty acids should make the cancer cells more susceptible to cryodamage and measurement of fatty acid composition of cancer cells may help individualize the temperature for cryotherapy. Also, the lipid alterations may affect the structure and functions of lipid rafts, which may enable the cancer cells to affect signaling mechanisms such as those involved in cell growth and apoptosis. Dietary or therapeutic interventions targeting lipid rafts may thus be an option for cancer treatment. 相似文献
3.
In normal adult rats some germ cells degenerate at several vulnerable steps of spermatogenesis. These are the type A spermatogonia, midpachytene spermatocytes, primary and secondary spermatocytes which degenerate during their respective maturation divisions and step 7 and 19 spermatids. In the present study, these degenerating cells were examined under the electron microscope, and their frequency was determined in toluidine blue stained semithin sections of testes from normal, hypophysectomized (at 5.5 days after operation) and hypophysectomized rats injected with FSH and LH separately or in combination. With the exception of the step 19 spermatids, the degenerating germ cells underwent necrosis in vacuolated spaces delimited by Sertoli cells. In the case of the affected step 19 spermatids, an apical cytoplasmic process of the Sertoli cell initially ensheathed a long segment of their flagellum, and then each degenerating cell was drawn deep in the seminiferous epithelium where it was phagocytozed by the Sertoli cell. Soon after hypophysectomy the incidence of degenerating mid-pachytene spermatocytes, step 7 and 19 spermatids which are present in stages VII or VIII of the cycle of the seminiferous epithelium, increased significantly. In contrast the number of degenerating primary or secondary spermatocytes during the meiotic divisions seen in stage XIV of the cycle or of any other germinal cell was not significantly modified. While the injection of FSH alone had no influence on the number of degenerating cells in hypophysectomized rats, injections of LH at the two doses administered (0.7 μg or 20 μg) reduced significantly the number of degenerating cells seen in stages VII-VIII of the cycle; combined injections of FSH and LH (20 μg) reduced the number of these degenerating cells to the normal low values. Thus it appeared that the mid-pachytene spermatocytes and the step 7 and 19 spermatids, all present in the adluminal compartment of the seminiferous epithelium in stages VII or VIII of the cycle, were more sensitive to the presence of absence of gonadotropic hormones than the other germ cells present in the seminiferous epithelium. 相似文献
4.
Lonnie Russell 《Developmental dynamics》1977,148(3):301-312
Desmosome-like junctions between Sertoli cells and germ cells (spermatogonia, spermatocytes and non-elongate spermatids) were observed in the adult rat testis. At all levels, certain features were characteristic of this relationship, the most prominent being a densification of the subsurface aspect of the plasma membranes of each cell. The Sertoli cell counterpart demonstrated an abundance of cytoplasmic fibrils which converged on the density, but no such feature was evident in the germ cell counterpart. The width of the intercellular space was variable, ranging in some regions from approximately 3–5 nm, to other regions of approximately 14–18 nm, the latter being representative of most areas of contact. A poorly represented, and often discontinous, intermediate dense line was observed in the intercellular space. Hypertonic fixative solutions containing dextrose were utilized to provoke tissue shrinkage and exaggeration of the intercellular space within the basal compartment of the testis. Cell separation was evident over most regions of the cells, except where desmosome-like contacts were present. Forces transmitted from one cell to another at desmosome-like contacts resulted in tearing of cellular fragments, while junctional regions of both cells remained intact. These observations indicate that desmosome-like junctions are strong adhesive sites between germ cells and Sertoli cells. 相似文献
5.
Smita Bhatia Wendy Landier Jacqueline Casillas Lonnie Zeltzer 《European journal of pediatrics》1995,154(9):757-791
Abstracts
15th Scientific Congress of the European Society for Pediatric Hematology and Immunology (ESPHI) Bingen, Germany, 23–26 August 1995 相似文献6.
Brian J. Cuffel Ph.D. Lonnie Snowden Ph.D. Mary Masland M.S.P.H. Giorgio Piccagli Ph.D. 《Community mental health journal》1996,32(2):109-124
The movement towards managed care in the public mental health system has surpassed efforts to develop a systematic literature concerning its theory, practice, and outcome. In particular little has been written about potential challenges and difficulties in translating managed care systems from their origins in the private sector to the delivery of public sector mental health services. This paper provides an overview of managed care definitions, organizational arrangements, administrative techniques, and roles and responsibilities using a theoretical framework adopted from economics referred to as principal-agent theory. Consistent with this theory, we assert that the primary function of the managed care organization is to act as agent for the payor and to manage the relationships between payors, providers, and consumers. From this perspective, managed care organizations in the public mental health system will be forced to manage an extremely complex set of relationships between multiple government payors, communities, mental health providers, and consumers. In each relationship, we have identified many challenges for managed care including the complexity of public financing, the vulnerable nature of the population served, and the importance of synchronization between managed care performance and community expectations for the public mental health system. In our view, policy regarding the role of managed care in the public mental health system must evolve from an understanding of the dynamics of government-community-provider-consumer agency relationships.Mary Masland, M.S.P.H., is Research Associate, Institute for Mental Health Services Research.Giorgio Piccagli, Ph.D., is Affiliated Investigator, Institute for Mental Health Service Research.This work was supported by the National Institute of Mental Health funded Center for Research on the Organization and Financing of Care for the Severely Mentally Ill (P50-MH43694). 相似文献
7.
Long-term neurologic and neurosensory sequelae in adult survivors of a childhood brain tumor: childhood cancer survivor study. 总被引:4,自引:0,他引:4
Roger J Packer James G Gurney Judy A Punyko Sarah S Donaldson Peter D Inskip Marilyn Stovall Yutaka Yasui Ann C Mertens Charles A Sklar H Stacy Nicholson Lonnie K Zeltzer Joseph P Neglia Leslie L Robison 《Journal of clinical oncology》2003,21(17):3255-3261
PURPOSE: To describe the neurologic and neurosensory deficits in children with brain tumors (BTs), compare incidence of these deficits with that of a sibling control group, and evaluate the factors associated with the development of these deficits. PATIENTS AND METHODS: Detailed questionnaires were completed on 1,607 patients diagnosed between 1970 and 1986 with a primary CNS tumor. Neurosensory and neurologic dysfunctions were assessed and results compared with those of a sibling control group. Medical records on all patients were abstracted, including radiotherapy dose and volume. RESULTS: Seventeen percent of patients developed neurosensory impairment. Relative to the sibling comparison group, patients surviving BTs were at elevated risk for hearing impairments (relative risk [RR], 17.3; P = <.0001), legal blindness in one or both eyes (RR, 14.8; P = <.0001), cataracts (RR, 11.9; P = <.0001), and double vision (RR, 8.8; P = <.0001). Radiation exposure greater than 50 Gy to the posterior fossa was associated with a higher likelihood of developing any hearing impairment. Coordination and motor control problems were reported in 49% and 26%, respectively, of survivors. Children receiving at least 50 Gy to the frontal brain regions had a moderately elevated risk for motor problems (RR, 2.0; P <.05). Seizure disorders were reported in 25% of patients, including 6.5% who had a late first occurrence. Radiation dose of 30 Gy or more to any cortical segment of the brain was associated with a two-fold elevated risk for a late seizure disorder. CONCLUSION: Children surviving BTs are at significant risk for both early and late neurologic or neurosensory sequelae. These sequelae need to be prospectively monitored. 相似文献
8.
Engineering the follicle microenvironment 总被引:1,自引:0,他引:1
In vitro ovarian follicle culture provides a tool to investigate folliculogenesis, and may one day provide women with fertility-preservation options. The application of tissue engineering principles to ovarian follicle maturation may enable the creation of controllable microenvironments that will coordinate the growth of the multiple cellular compartments within the follicle. Three-dimensional culture systems can preserve follicle architecture, thereby maintaining critical cell-cell and cell-matrix signaling lost in traditional two-dimensional attached follicle culture systems. Maintaining the follicular structure while manipulating the biochemical and mechanical environment will enable the development of controllable systems to investigate the fundamental biological principles underlying follicle maturation. This review describes recent advances in ovarian follicle culture, and highlights the tissue engineering principles that may be applied to follicle culture, with the ultimate objective of germline preservation for females facing premature infertility. 相似文献
9.
Dr. Lonnie B. Hanauer MD 《Arthritis \u0026amp; Rheumatology》1972,15(6):636-640
A 57-year-old woman developed joint pain, deformity and cutaneous nodules. Reticulohistiocytosis was diagnosed after skin biopsy. Nodule formation and progressive arthritis continued for almost 2 years but appeared to cease when treatment with cyclophosphamide began. 相似文献
10.
Xuan Wang Lorraine P. Yomano James Y. Lee Sean W. York Huabao Zheng Michael T. Mullinnix K. T. Shanmugam Lonnie O. Ingram 《Proceedings of the National Academy of Sciences of the United States of America》2013,110(10):4021-4026
Pretreatments such as dilute acid at elevated temperature are effective for the hydrolysis of pentose polymers in hemicellulose and also increase the access of enzymes to cellulose fibers. However, the fermentation of resulting syrups is hindered by minor reaction products such as furfural from pentose dehydration. To mitigate this problem, four genetic traits have been identified that increase furfural tolerance in ethanol-producing Escherichia coli LY180 (strain W derivative): increased expression of fucO, ucpA, or pntAB and deletion of yqhD. Plasmids and integrated strains were used to characterize epistatic interactions among traits and to identify the most effective combinations. Furfural resistance traits were subsequently integrated into the chromosome of LY180 to construct strain XW129 (LY180 ΔyqhD ackA::PyadC′fucO-ucpA) for ethanol. This same combination of traits was also constructed in succinate biocatalysts (Escherichia coli strain C derivatives) and found to increase furfural tolerance. Strains engineered for resistance to furfural were also more resistant to the mixture of inhibitors in hemicellulose hydrolysates, confirming the importance of furfural as an inhibitory component. With resistant biocatalysts, product yields (ethanol and succinate) from hemicellulose syrups were equal to control fermentations in laboratory media without inhibitors. The combination of genetic traits identified for the production of ethanol (strain W derivative) and succinate (strain C derivative) may prove useful for other renewable chemicals from lignocellulosic sugars. 相似文献