Medicine and Health Sciences Commons^™

Microcirculation: Electrophysiological Basis For The Response Of Endothelial Cells To Inflammatory Mediators-Bradykinin, Kai Miao

Electronic Theses and Dissertations

Using conventional microelectrodes, I studied the electrical basis for determining the resting V$\sb{\rm m}$ in intact EC's from hamsters. The resting V$\sb{\rm m}$ were found to be $-$40 mV for aortic EC's and $-$43 mV for vena caval EC's. The contributions of ions to the resting V$\sb{\rm m}$ of aortic EC's were compared in terms of the transference number (t$\sb{\rm ion}$). To develop a technique for in situ monitoring changes in V$\sb{\rm m}$ of postcapillary venular EC's in the hamster mesentery, a voltage-sensitive fluorescent probe, bisoxonol, was used to load the cells and the fluorescence signals were analyzed under an …

Cytokines And Ovulation In The Mouse Ovary, Jong G. Kim

Electronic Theses and Dissertations

Ovulation has been hypothesized as an inflammatory process. Interleukin(IL)-1$\alpha$, IL-1$\beta$ and tumor necrosis factor(TNF)-$\alpha$ are potent cytokines produced from macrophages and various other cell types, and are pivotal components of inflammation. Although previous studies have investigated cytokine activities in the reproductive system, there is little information on their precise localization and activities during the periovulatory period. To investigate the role of cytokines in ovulation, experiments were designed to determine the immunohistochemical localization and time specific production of cytokines IL-1 and TNF-$\alpha$ using a mouse model at 36h, 12h, 6h, 2h before ovulation, and at 6h and 18h after ovulation in …

Stab Wounds To Rat Brains : Demyelination, Remyelination And The Cellular Response, Particularly Of Oligodendrocytes, Xie Dangci

Loma Linda University Electronic Theses, Dissertations & Projects

The present body of knowledge concerning the results of central nervous system injury is incomplete and controversial. The role of oligodendrocytes, the cells involved in phagocytosis, the stages of demyelination, and the evidence for remyelination are of interest. Following stab wounds to rat brain cortex, corpus callosum and hippocampus, the animals were examined at 4,7,11,18,23,29,45,60 and 70 days postoperation (dpo). To help in the identification of cells immunocytochemical markers for astrocytes and immature oligodendrocytes were used. These were labels for glial fibrillary acidic protein (GFAP) and myelin/oligodendrocyte specific protein (MOSP) respectively. Light and electron microscopy were correlated using conventionally prepared …

Short And Long Term Effects Of Proton Microbeam Irradiation : In The Lateral Geniculate Nucleus Of Felis Domesticus, Chad Sherwood Reder

Loma Linda University Electronic Theses, Dissertations & Projects

Little is known of the effects of proton irradiation on neural tissue. A 1.0 mm microbeam was used on the cat lateral geniculate nucleus (LGN) to quantify the short term (< 3 months) and long term (< 9 months) effects of radiation damage. The LGN is a large structure with well defined afferent, efferent, and receptive field properties.

Electrophysiological and histological techniques were used to examine the effects of the microbeam at 60, 40, and 16 Gy, administered as a single bolus. Recordings of light evoked responses in the LGN were obtained using microelectrodes in nine animals within 12 weeks of irradiation, and 6 animals within 36 weeks of irradiation. Receptive fields were mapped onto a tangent screen using standard receptive field techniques. Histological measures included afferent …

Impairment Of The Cellular Immune Response In Acute Murine Toxoplasmosis: Regulation Of Interleukin 2 Production And Macrophage-Mediated Inhibitory Effects., Sakhina Haque, Imtiaz Khan, Azizul Haque, Lloyd Kasper

Dartmouth Scholarship

Depression of the cellular immune response to Toxoplasma gondii has been reported in both mice and humans. The present study was undertaken to determine the kinetics and mechanism of the observed downregulation of interleukin 2 (IL-2) production during experimental murine toxoplasmosis. For these investigations, the cell-mediated immune response to the wild type (PTg) was compared with that to the less-virulent mutant parasite (PTgB), which is deficient in the major surface antigen, p30 (SAG-1). Spleen cells from infected A/J mice failed to proliferate in response to Toxoplasma antigens during the first week of infection. Both PTg- and PTgB-infected A/J mice exhibited …

Denervation Supersensitivity Of The Rat Vas Deferens: A Role For Protein Kinase C, Sonny T. Abraham

Electronic Theses and Dissertations

A role for protein kinase C (PKC) in the denervation-induced supersensitivity of the rat vas deferens was investigated. Chronic, surgical denervation of the rat vas deferens (up to 8 days) resulted in tissues that produced enhanced contractile responses to norepinephrine (NE) in isolated organ baths. Single challenges of NE (10 $\mu$M) produced 0.6 $\pm$ 0.1 g of maximal tension in the control vas whereas in the paired, denervated tissue 2.2 $\pm$ 0.3 g of tension was recorded (n = 6). Cumulative concentration-effect curves to NE produced in the denervated vas deferens were shifted 18-fold to the left of the control …

Differential Role Of The Endothelium In Regulating Microvascular Blood Flow, Tao Tang

Electronic Theses and Dissertations

The vascular endothelial cell (EC) plays an important role in regulating vascular tone and local blood flow by sensing chemical and mechanical stimuli on the vascular wall and releasing a host of vasoactive substances upon activations of endogenous or exogenous vasoactive substances. The central hypothesis is that local control of blood now and autoregulatory behavior in the microcirculation is distinctive at different levels of the vasculature and is dependent on the cellular activities of the EC and its interaction with the local environment. The in vivo as well as the ex vivo, flow-controlled preparations of the hamster cheek pouch were …

Characterization Of The Vasoactivity Of Tachykinins In Isolated Rat Kidney: Functional Studies And In Vitro Receptor Autoradiography, Yuejin Chen

Electronic Theses and Dissertations

Although tachykinins have potent vascular actions, their effect on renal resistance blood vessels is currently unknown. The vasoactive properties of tachykinins and related analogs were assessed in isolated perfused rat kidney. At a basal perfusion pressure (PP) of 75 $\pm$ 6 mm Hg (n = 5), bolus injections of substance P (SP) had no significant vasoactive effect. Following a sustained increase in baseline PP (134 $\pm$ 10 mm Hg) produced by phenylephrine (1 $\mu$M), SP evoked a dose-dependent increase in PP. The largest dose of SP increased PP by 60 $\pm$ 5 mm Hg. The vasoconstrictor response to SP was …

Conjoined Twins - A Review Of Literature With Two Case Studies, Naaeem Uz-Zafar Khan, Nadeem Ullah Khan, Khalid Matin, Adnan Zaidi

Department of Emergency Medicine

Two cases of conjoined twins have been reported. A review of literature is given.

Bcl-2 Protein Expression Is Widespread In The Developing Nervous-System And Retained In The Adult Pns, Diane E. Merry, Deborah J. Veis, William F. Hickey, Stanley J. Korsmeyer

Dartmouth Scholarship

Cell death is a common feature of neural development in all vertebrates. The bcl-2 proto-oncogene has been shown to protect a variety of cell types from programmed cell death. We have examined the distribution of bcl-2 protein in the developing and adult nervous systems. bcl-2 protein is widespread during embryonic development. Proliferating neuroepithelial cells of ventricular zones as well as the postmitotic cells of the cortical plate, cerebellum, hippocampus and spinal cord express bcl-2. Postnatally, bcl-2 is principally retained in the granule cells of the cerebellum and dentate gyrus of the hippocampus. bcl-2 expression in the CNS declines with aging. …

Review Of The P53 Tumor Suppressor Gene And Its Role In Gliomas, James Dearing Christian

Theses and Dissertations

The following review of the p53 tumor suppressor gene will be discussed with particular attention to its role in human gliomas, as well as the various advances that have brought this molecule to the forefront of cancer research. A review of tumorigenesis focuses on the molecular mechanisms that convey neoplastic characteristics upon a normal cell. It is discussed how the coordinate advances in chromosome analysis and molecular techniques enabled the p53 gene to be categorized as a "tumor suppressor gene" and applied to various forms of cancer, including colorectal and lung carcinoma. The focus of the review will be on …

Effects Of Antihypertensive Medications On Quality Of Life In Elderly Hypertensive Women, Sydney H. Croog, Merrill F. Elias, Theodore Colton, Robert M. Baume, Sandra R. Leiblum, C David Jones, H Mitchell Perry, W Dallas Hall

Maine-Syracuse Longitudinal Papers

The impact of antihypertensive medications on the quality of life of elderly hypertensive women has rarely been systematically evaluated in large clinical trials using drugs from the new generations of pharmaceutic preparations. We carried out a multicenter, randomized double-blind clinical trial with 309 hypertensive women aged 60 to 80 years to assess effects of atenolol, enalapril, and isradipine on measures of quality of life over a 22-week period. The patients had mild to moderate hypertension. Hydrochlorothiazide was added to treatment if monotherapy was inadequate in lowering blood pressure. At the conclusion of the trial the three drug groups did not …

Safe At The Shoulder, Daniel Cipriani

Physical Therapy Faculty Articles and Research

The key to preventing shoulder injuries is understanding the anatomy of the shoulder complex and how the body's other muscles affect the throwing motion

Radiosurgery For Malignant Brain Tumors, Michael Jino Yun

Theses and Dissertations

Radiosurgery using the Linear Accelerator or the Gamma Knife has proven to be an effective treatment modality for malignant brain tumors. In comparison to other treatments, radiosurgery can be performed on an outpatient basis and is noninvasive (Table 5). Due to the functional properties of radiosurgical devices, they are ideal for patients who are unable to undergo surgical removal of their brain tumors. The sharp dose drop—off beyond the tumor margin allows for high dosage tumor irradiation while sparing normal brain tissue. Many procedures that involve radiosurgery use it as a ”boost” therapy in conjunction with surgical resection and whole …

Cortical Type 2 Astrocytes Are Not Dye Coupled Nor Do They Express The Major Gap Junction Genes Found In The Central Nervous System, Daniel Belliveau, C. Naus

Daniel J. Belliveau

The O‐2A progenitor cell first described from the rat optic nerve is a bipotential precursor of oligodendrocytes and type 2 astrocytes. Each cell expresses specific markers that distinguish them as unique cell types. O‐2A progenitors cultured in high serum preferentially differntiate into type 2 astrocytes and when exposed to defined medium or low serum develop along the oligodendrocyte lineage. We analyzed the gap junction gene expression of type 2 astrocytes to determine if they are coupled to form a syncytium, like their type 1 astrocyte counterparts. Dye coupling experiments demonstrated that cortical type 2 astrocytes are not coupled, while type …