bluuebunny/crossref_metadata_2025 huggingface dataset:
Synaptic Release of Serotonin Induced by Stimulation of the Raphe Nucleus Promotes Plateau Potentials in Spinal Motoneurons of the Adult Turtle
Authors: Perrier Jean-François , Delgado-Lezama Rodolfo
Published: August 2005

Serotonin (5-HT) is a major modulator of the CNS. In motoneurons recorded in slices of the spinal cord, 5-HT promotes plateau potentials mediated by the activity of low-threshold L-type calcium channels (CaV1.3). However, no direct evidence has shown that 5-HT actually promotes plateau potentials under physiological conditions. Here, we investigate how release of 5-HT induced by activation of the raphe nucleus modulates intrinsic properties of spinal motoneurons. We developed an integrated preparation of the brainstem left in continuity with the cervical segments of the spinal cord from adult turtles. Electrical stimulation of the raphe nucleus increased the excitability of motoneurons by decreasing the amplitude of the afterhyperpolarization following action potentials and by promoting plateau potentials. Antagonists of 5-HT2receptors applied in the vicinity of motoneurons inhibited the facilitation of plateaus. In a slice preparation in which glutamatergic, GABAergic, and glycinergic ionotropic synaptic transmission was blocked, stimulation of the dorsolateral funiculus facilitated a plateau potential by promoting a voltage-sensitive persistent inward current. This effect was inhibited by the addition of antagonists for 5-HT2receptors. Our study suggests that CaV1.3 channels are regulated by 5-HT released from raphe spinal synaptic terminals via 5-HT2receptors.
Voltage-Gated Sodium Channels Improve Contrast Sensitivity of a Retinal Ganglion Cell
Authors: Dhingra Narender K. , Freed Michael A. , Smith Robert G.
Published: August 2005

Voltage-gated channels in a retinal ganglion cell are necessary for spike generation. However, they also add noise to the graded potential and spike train of the ganglion cell, which may degrade its contrast sensitivity, and they may also amplify the graded potential signal. We studied the effect of blocking Na+channels in a ganglion cell on its signal and noise amplitudes and its contrast sensitivity. A spot was flashed at 1–4 Hz over the receptive field center of a brisk transient ganglion cell in an intact mammalian retina maintainedin vitro. We measured signal and noise amplitudes from its intracellularly recorded graded potential light response and measured its contrast detection thresholds with an “ideal observer.” When Na+channels in the ganglion cell were blocked with intracellular lidocaineN-ethyl bromide (QX-314), the signal-to-noise ratio (SNR) decreased (p< 0.05) at all tested contrasts (2–100%). Likewise, bath application of tetrodotoxin (TTX) reduced the SNR and contrast sensitivity but only at lower contrasts (≤50%), whereas at higher contrasts, it increased the SNR and sensitivity. The opposite effect of TTX at high contrasts suggested involvement of an inhibitory surround mechanism in the inner retina. To test this hypothesis, we blocked glycinergic and GABAergic inputs with strychnine and picrotoxin and found that TTX in this case had the same effect as QX-314: a reduction in the SNR at all contrasts. Noise analysis suggested that blocking Na+channels with QX-314 or TTX attenuates the amplitude of quantal synaptic voltages. These results demonstrate that Na+channels in a ganglion cell amplify the synaptic voltage, enhancing the SNR and contrast sensitivity.
Initiation, Propagation, and Termination of Epileptiform Activity in Rodent NeocortexIn VitroInvolve Distinct Mechanisms
Authors: Pinto David J. , Patrick Saundra L. , Huang Wendy C. , Connors Barry W.
Published: September 2005

Waves of epileptiform activity in neocortex have three phenomenological stages: initiation, propagation, and termination. We use a well studied model of epileptiform activityin vitroto investigate directly the hypothesis that each stage is governed by an independent mechanism within the underlying cortical circuit. Using the partially disinhibited neocortical slice preparation, activity is induced and modulated using neurotransmitter receptor antagonists and is measured using both intracellular recordings and a linear array of extracellular electrodes. We find that initiation depends on both synaptic excitation and inhibition and entails a slow process of recruitment at discrete spatial locations within cortical layer 5 but not layer 2/3. Propagation depends on synaptic excitation but not inhibition and is a fast process that involves neurons across the spatial extent of the slice and in all cortical layers. Termination is modulated by synaptic excitation and inhibition. In space, termination occurs reliably at discrete locations. In time, termination is characterized by a strong depolarizing shift (block) and recovery of neurons in all cortical layers. These results suggest that the phenomenological stages of epileptiform events correspond to distinct mechanistic stages.
Bradykinin Produces Pain Hypersensitivity by Potentiating Spinal Cord Glutamatergic Synaptic Transmission
Authors: Wang Haibin , Kohno Tatsuro , Amaya Fumimasa , Brenner Gary J. , Ito Nobuko , Allchorne Andrew , Ji Ru-Rong , Woolf Clifford J.
Published: August 2005

Bradykinin, an inflammatory mediator, sensitizes nociceptor peripheral terminals reducing pain threshold. We now show that the B2kinin receptor is expressed in rat dorsal horn neurons and that bradykinin, a B2-specific agonist, augments AMPA- and NMDA-induced, and primary afferent-evoked EPSCs, and increases the frequency and amplitude of miniature EPSCs in superficial dorsal horn neuronsin vitro. Administration of bradykinin to the spinal cordin vivoproduces, moreover, an NMDA-dependent hyperalgesia. We also demonstrate that nociceptive inputs result in the production of bradykinin in the spinal cord and that an intrathecal B2-selective antagonist suppresses behavioral manifestations of central sensitization, an activity-dependent increase in glutamatergic synaptic efficacy. Primary afferent-evoked central sensitization is, in addition, reduced in B2receptor knock-out mice. We conclude that bradykinin is released in the spinal cord in response to nociceptor inputs and acts as a synaptic neuromodulator, potentiating glutamatergic synaptic transmission to produce pain hypersensitivity.
Chronic Wasting Disease of Elk: Transmissibility to Humans Examined by Transgenic Mouse Models
Authors: Kong Qingzhong , Huang Shenghai , Zou Wenquan , Vanegas Difernando , Wang Meiling , Wu Di , Yuan Jue , Zheng Mengjie , Bai Hua , Deng Huayun , Chen Ken , Jenny Allen L. , O'Rourke Katherine , Belay Ermias D. , Schonberger Lawrence B. , Petersen Robert B. , Sy Man-Sun , Chen Shu G. , Gambetti Pierluigi
Published: August 2005

Chronic wasting disease (CWD), a prion disease affecting free-ranging and captive cervids (deer and elk), is widespread in the United States and parts of Canada. The large cervid population, the popularity of venison consumption, and the apparent spread of the CWD epidemic are likely resulting in increased human exposure to CWD in the United States. Whether CWD is transmissible to humans, as has been shown for bovine spongiform encephalopathy (the prion disease of cattle), is unknown. We generated transgenic mice expressing the elk or human prion protein (PrP) in a PrP-null background. After intracerebral inoculation with elk CWD prion, two lines of “humanized” transgenic mice that are susceptible to human prions failed to develop the hallmarks of prion diseases after >657 and >756 d, respectively, whereas the “cervidized” transgenic mice became infected after 118–142 d. These data indicate that there is a substantial species barrier for transmission of elk CWD to humans.
Developmentally distinct in vivo effects of FSH on proliferation and apoptosis during testis maturation
Authors: Meachem Sarah J , Ruwanpura Saleela M , Ziolkowski Jessica , Ague Jacquelyn M , Skinner Michael K , Loveland Kate L
Published: August 2005

The critical influence of follicle stimulating hormone (FSH) on male fertility relates both to its impact on Sertoli cell proliferation in perinatal life and to its influence on the synthesis of Sertoli cell-derived products essential for germ cell survival and function in the developing adult testis. The nature and timing of this shift of germ cells to their reliance on specific Sertoli cell-derived products are not defined. Based on existing data, it is apparent that the dominant function of FSH shifts between 9 and 18 day postpartum (dpp) during the first wave of spermatogenesis from driving Sertoli cell proliferation to support germ cells. To enable comprehensive analysis of the impact of acute in vivo FSH suppression on Sertoli and germ cell development, FSH was selectively suppressed in Sprague–Dawley rats by passive immunisation for 2 days and/or 4 days prior to testis collection at 3, 9 and 18 dpp. The 3 dpp samples displayed no measurable changes, while 4 days of FSH suppression decreased Sertoli cell proliferation and numbers in 9 dpp, but not 18 dpp, animals. In contrast, germ cell numbers were unaffected at 9 dpp but decreased at 18 dpp following FSH suppression, with a corresponding increase in germ cell apoptosis measured at 18 dpp. Sixty transcripts were measured as changed at 18 dpp in response to 4 days of FSH suppression, as assessed using Affymetrix microarrays. Some of these are known as Sertoli cell-derived FSH-responsive genes (e.g. StAR, cathepsin L, insulin-like growth factor binding protein-3), while others encode proteins involved in cell cycle and survival regulation (e.g. cyclin D1, scavenger receptor class B 1). These data demonstrate that FSH differentially affects Sertoli and germ cells in an age-dependent manner in vivo, promoting Sertoli cell mitosis at day 9, and supporting germ cell viability at day 18. This model has enabled identification of candidate genes that contribute to the FSH-mediated pathway by which Sertoli cells support germ cells.
Redox up-regulated expression of rat liver manganese superoxide dismutase and Bcl-2 by thyroid hormone is associated with inhibitor of κB-α phosphorylation and nuclear factor-κB activation
Authors: Fernández Virginia , Tapia Gladys , Varela Patricia , Castillo Iván , Mora Catalina , Moya Francisco , Orellana Myriam , Videla Luis A
Published: August 2005

Recently, we demonstrated that 3,3′,5-triiodothyronine (T3) induces oxidative stress in rat liver, with enhancement in the DNA binding of nuclear factor-κB (NF-κB) and the NF-κB-dependent expression of tumor necrosis factor-α (TNF-α). In this study, we show that T3 administration (daily doses of 0.1 mg/kg i.p. for three consecutive days) elicited a calorigenic response and higher liver O2 consumption rates, with increased serum levels of TNF-α (ELISA), liver inhibitor of κB (IκB-α) phosphorylation (Western blot analysis), and hepatic NF-κB DNA binding (EMSA) at 56–72 h after treatment. Within this time interval, liver manganese superoxide dismutase (MnSOD) activity and the protein expression of MnSOD and Bcl-2 are enhanced. These changes are abrogated by the administration of α-tocopherol (100 mg/kg i.p.) prior to T3. It is concluded that T3 treatment leads to the redox upregulation of MnSOD and Bcl-2 in rat liver, in association with TNF-α release and activation of the IκB-α kinase/NF-κB cascade, which may constitute a protective mechanism against free radical toxicity involving cell death signaling.
Gastric immunolocalization and plasma profiles of acyl-ghrelin in fasted and fasted-refed prepuberal gilts
Authors: Govoni N , De Iasio R , Cocco C , Parmeggiani A , Galeati G , Pagotto U , Brancia C , Spinaci M , Tamanini C , Pasquali R , Ferri G-L , Seren E
Published: August 2005

Ghrelin is a peripheral circulating hormone, mainly released from the stomach, which can stimulate food intake. We studied fed, fasted and fasted-refed prepuberal gilts in order to outline possible changes in gastric mucosal ghrelin cells and in plasma ghrelin profiles in reponse to food deprivation. Acyl-ghrelin-immunoreactive cells were numerous in oxyntic glands, less abundant in cardiac glands and least frequent in pyloric glands, with the addition of a minor population of labelled cells in the gastric pit mucosa. When fed and fasted animals were compared (72-h fast versus fed; n=4 each), no clear-cut differences were revealed in labelled cell numbers, nor in their staining intensity. An RIA for plasma porcine acyl-ghrelin (n-octanoylated at Ser-3), not recognizing des-acyl-ghrelin, was validated. Plasma acyl-ghrelin progressively increased upon fasting (over 6, 12, 24 and 48 h); ghrelin levels significantly (P<0.05) higher than those prefast were reached at 72 h. After refeeding, plasma ghrelin was rapidly restored to basal values by 6 h. In the same animals, plasma insulin was significantly reduced throughout the fasting period (6–72 h), while rapidly increasing after refeeding. Non-esterified fatty acid levels increased during fasting (12–72 h) and rapidly returned to low values after refeeding. In conclusion, the present study demonstrates that starvation and refeeding influence ghrelin plasma level in prepuberal gilts. The absence of detectable changes in ghrelin cells, as seen in immunohistochemistry, could be due to a large intracellular storage of potentially releasable acylghrelin.
Short-term continuous infusion of human parathyroid hormone 1–34 fragment is catabolic with decreased trabecular connectivity density accompanied by hypercalcemia in C57BL/J6 mice
Authors: Iida-Klein A , Lu S Shou , Kapadia R , Burkhart M , Moreno A , Dempster D W , Lindsay R
Published: August 2005

Parathyroid hormone (PTH) stimulates bone resorption as well as bone formation in vivo and in organ culture. The catabolic actions of PTH have been recognized in patients with hyperparathyroidism, or with acute infusion of the N-terminal 1–34 fragment of human PTH (hPTH1–34). Whereas the anabolic actions of daily injection with PTH have been well studied in both humans and mice, the catabolic actions of PTH on murine bone remain to be defined. To do this we sought to create a model with short-term, sustained hyperparathyroidism using osmotic infusion pumps. We treated 10-week-old female C57BL/J6 mice with continuous infusion of hPTH1–34 (8.1 pmol/0.25 μl per h, equivalent to 40 μg/kg per day) or vehicle for 2 weeks, using Alzet osmotic pumps. Bone mineral density (BMD), serum total calcium, hPTH1–34, mouse intact PTH (mPTH1–84), osteocalcin and mouse tartrate-resistant acid phosphatase (mTRAP) activity, and microarchitectural variables of the distal femur were measured. Separately, we compared the effects of intermittent daily injection of hPTH1–34 (40 μg/kg per day) with continuous infusion of hPTH1–34 on BMD and bone markers. Exogenous hPTH1–34 was detected only in the PTH-infused mice. Both intermittent and continuous treatment with hPTH1–34 markedly suppressed endogenous mPTH1–84, but only the latter induced hypercalcemia. Daily PTH injection significantly increased both serum osteocalcin and mTRAP, while continuous PTH infusion showed a strong trend to stimulate mTRAP, with a slight but non-significant increase in osteocalcin. There were significant differences in BMD at all sites between animals treated with the same daily dose of intermittent and continuous hPTH1–34. Microcomputed tomography (μCT) analysis of the distal femurs revealed that hPTH1–34 infusion significantly decreased trabecular connectivity density (P<0.05). Thus, the murine bone response to continuous PTH infusion was quite different from that seen with daily PTH injection. Short-term infusion of hPTH1–34 appears to be a good model to study the mechanisms underlying the catabolic action of PTH in mice.
Somatic mutations of the thyroid-stimulating hormone receptor gene in feline hyperthyroidism: parallels with human hyperthyroidism
Authors: Watson S G , Radford A D , Kipar A , Ibarrola P , Blackwood L
Published: August 2005

Hyperthyroidism is the most common endocrinopathy in cats, and is both clinically and histopathologically very similar to human toxic nodular goitre (TNG). Molecular studies on human TNG have revealed the presence of mis-sense mutations in the thyroid-stimulating hormone receptor (TSHR) gene, most frequently in exon 10. Our hypothesis was that similar mutations exist in hyperthyroid cats. Genomic DNA was extracted from 134 hyperplastic/ adenomatous nodules (from 50 hyperthyroid cats), and analysed for the presence of mutations in exon 10 of the TSHR gene. 11 different mutations were detected, one silent and 10 mis-sense, of which nine were somatic mutations. 28 of the 50 cats (67/134 nodules) had at least one mis-sense mutation. The mis-sense mutations were Met-452→Thr in 17 cats (35 nodules), Ser-504→Arg (two different mutational forms) in two cats (two nodules), Val-508→Arg in one cat (three nodules), Arg-530→Gln in one cat (two nodules), Val-557→Leu in 13 cats (36 nodules), Thr-631→Ala or Thr-631→Phe (each mutation seen in one nodule of one cat), Asp-632→Tyr in six cats (10 nodules) and Asp-632→His in one cat (one nodule). Five of these mutations have been associated previously with human hyperthyroidism. Of the 41 cats for which more than one nodule was available, 14 had nodules with different mutations. The identification of a potential genetic basis for feline hyperthyroidism is novel, increases our understanding of the pathogenesis of this significant feline disease, and confirms its similarity to TNG.
Health and Health Care Among Male-to-Female Transgender Persons Who Are HIV Positive
Authors: Melendez Rita M. , Exner Theresa A. , Ehrhardt Anke A. , Dodge Brian , Remien Robert H. , Rotheram-Borus Mary-Jane , Lightfoot Marguerita , Hong Daniel ,   The National Institute Of Mental Health Healthy Living Project Team
Published: August 2005

Recent studies have reported high rates of HIV infection among male-to-female transgender persons, but little research has examined how male-to-female transgender persons manage living with HIV. We compared demographic and health characteristics of 59 male-to-female transgender persons who were HIV positive with 300 nontransgender control subjects who were HIV positive. We found several demographic differences between the groups but no significant differences in HIV-related health status. Male-to-female transgender persons were less likely than the control group to take highly active antiretroviral therapy.
A Semiparametric Analysis of the Relationship of Body Mass Index to Mortality
Authors: Gronniger Jerome Timothy
Published: August 2005

Objectives. I used a semi-parametric analysis of the relationship between body mass index (BMI) and mortality to assess the adequacy of conventional BMI categories for planning public health programs to reduce mortality.

Methods. I linked supplements from the 1987 and 1989 versions of the National Health Interview Survey to the 1995 Multiple Cause of Death File to obtain mortality information. I constructed nonlinear estimates of the association between BMI and mortality using a semiparametric regression technique.

Results. The mortality risk among “normal” weight men (i.e., those in the BMI range of 20 to 25 kg/m2) was as high as that among men in the mild obesity category (BMIs of 30–35 kg/m2), with a minimum risk observed at a BMI of approximately 26 kg/m2. Among women, the mortality risk was smallest at approximately 23 to 24 kg/m2, with the risk increasing steadily with BMIs above 27 kg/m2. In each specification, the slope of the line was small and volatile through the BMI range of 20 to 35 kg/m2, suggesting negligible risk differences with minor differences in weight for much of the population.

Conclusions. Traditional BMI categories do not conform well to the complexities of the BMI–mortality relationship. In concurrence with conclusions from previous literature, I found that the current definitions of obesity and overweight are imprecise predictors of mortality risk.
Diabetes Portrayals in North American Print Media: A Qualitative and Quantitative Analysis
Authors: Rock Melanie
Published: August 2005

Objectives. This study investigated how media coverage has portrayed diabetes as newsworthy.

Methods. The quantitative component involved tabulating diabetes coverage in 2 major Canadian newspapers, 1988–2001 and 1991–2001. The qualitative component focused on high-profile coverage in 2 major US magazines and 2 major Canadian newspapers, 1998–2000.

Results. Although coverage did not consistently increase, the quantitative results suggest an emphasis on linking diabetes with heart disease and mortality to convey its seriousness. The qualitative component identified 3 main ways of portraying type 2 diabetes: as an insidious problem, as a problem associated with particular populations, and as a medical problem.

Conclusions. Overall, the results suggest that when communicating with journalists, researchers and advocates have stressed that diabetes maims and kills. Yet even when media coverage acknowledged societal forces and circumstances as causes, the proposed remedies did not always include or stress modifications to social contexts. Neither the societal causes of public health problems nor possible societal remedies automatically received attention from researchers or from journalists. Skilled advocacy is needed to put societal causes and solutions on public agendas.
Risk Factors for Long-Term Homelessness: Findings From a Longitudinal Study of First-Time Homeless Single Adults
Authors: Caton Carol L. M. , Dominguez Boanerges , Schanzer Bella , Hasin Deborah S. , Shrout Patrick E. , Felix Alan , McQuistion Hunter , Opler Lewis A. , Hsu Eustace
Published: August 2005

Objectives. We examined risk factors for long-term homelessness among newly homeless men and women who were admitted to New York City shelters in 2001 and 2002.

Methods. Interviews were conducted with 377 study participants upon entry into the shelter and at 6-month intervals for 18 months. Standardized assessments of psychiatric diagnosis, symptoms, and coping skills; social and family history; and service use were analyzed. Kaplan—Meier survival analysis and Cox regression were used to examine the association between baseline assessments and duration of homelessness.

Results. Eighty-one percent of participants returned to community housing during the follow-up period; the median duration of homelessness was 190 days. Kaplan—Meier survival analysis showed that a shorter duration of homelessness was associated with younger age, current or recent employment, earned income, good coping skills, adequate family support, absence of a substance abuse treatment history, and absence of an arrest history. Cox regression showed that older age group P<.05) and arrest history (P<.01) were the strongest predictors of a longer duration of homelessness.

Conclusions. Identification of risk factors for long-term homelessness can guide efforts to reduce lengths of stay in homeless shelters and to develop new preventive interventions.
Capturing Intervention Effects Over Time: Reanalysis of a Critical Time Intervention for Homeless Mentally Ill Men
Authors: Lennon Mary Clare , McAllister William , Kuang Li , Herman Daniel B.
Published: August 2005

Objectives. We analyzed whether a method for identifying latent trajectories—latent class growth analysis (LCGA)—was useful for understanding outcomes for individuals subject to an intervention.

Methods. We used LCGA to reanalyze data from a published study of mentally ill homeless men in a critical time intervention (CTI) program. In that study, 96 men leaving a shelter’s onsite psychiatric program were randomly assigned to experimental and control groups. The former received CTI services and the latter usual services. Each individual’s housing circumstances were observed for 18 months after program initiation. Our outcome measure was monthly homelessness: a person was considered homeless in a month if he was homeless for even 1 night that month.

Results. Four latent classes were found among the control group, but just 3 among the experimental group. Control, but not experimental, group individuals showed a small class of chronically homeless men. The size of the never-homeless class was 19 percentage points larger for the experimental than for the control group. J- and inverted-U-shaped patterns were also found among both groups, but with important differences in timing of patterns.

Conclusions. Our results reveal effects not apparent in the original analysis, suggesting that latent class growth models improve intervention evaluation.
SPEAKING OUT to Improve the Health of Inmates
Authors: Heines Vivienne
Published: August 2005

Prison public health is becoming increasingly important to our society as growing numbers of men and women are incarcerated and later released. Numerous studies indicate that the prison population has a higher risk of certain infectious diseases and a higher rate of mental illness than the general population.

Two community leaders, Dr Melanie Spector in the area of public health and Judge Steven Leifman in the judicial system, have addressed the vital issues of womens health and mental illness, respectively. Their efforts have had a positive impact both on prisoners themselves and on the overall health of their communities.
3‐D Reconstruction of Neurons from Multichannel Confocal Laser Scanning Image Series
Authors: Wouterlood Floris G.
Published: August 2005

A confocal laser scanning microscope (CLSM) collects information from a thin, focal plane and ignores out‐of‐focus information. The operator configures separate channels (laser, filters, detector settings) for each fluorochrome used in a particular experiment. Then, 3‐D reconstructions are made from Z‐series of confocal images: one series per channel. Channel signal separation is extremely important and measures to avoid bleaching are vital. Post‐acquisition deconvolution of the image series is then performed to increase resolution. In the 3‐D reconstruction program described in this unit, reconstructions can be inspected in real time from any viewing angle. By altering viewing angles and by switching channels off and on, the spatial relationship of 3‐D‐reconstructed structures with respect to structures seen in other channels can be studied. Since each brand of CLSM, computer program, and 3‐D reconstruction package has its own proprietary set of procedures, a general approach is provided wherever possible.
Two‐Photon Imaging in Live Rodents
Authors: Belluscio Leonardo
Published: August 2005

Two‐photon imaging is an innovative optical technique that has quickly become state of the art for imaging fluorescent signals in a variety of organisms. With many advantages over conventional confocal microscopy, such as greater image resolution, deeper access (∼400 µm), and much less photo damage, two‐photon microscopy has already proven to be an extremely useful tool for imaging live cells or tissue. Due to its tremendous versatility, recent efforts have adapted this technique to allow visualization of fluorescent cells directly in living animals. This unit describes a basic procedure for performing two‐photon imaging in vivo as applied to the dorsal surface of the brain in live anesthetized mice or rats. The protocol outlines a surgical preparation to enable the capture of stable, high‐resolution (<1 µm) images of fluorescently labeled neurons in intact brain with very little detrimental effect to either cells or tissue.
Chronic Intravenous Drug Self‐Administration in Rats and Mice
Authors: Thomsen Morgane , Caine S. Barak
Published: August 2005

Chronic intravenous drug self‐administration in rodents is a useful procedure for predicting the abuse liability of novel drugs in humans, for evaluating candidate treatments for drug abuse and dependence, and for studying the biological basis of addiction. This unit focuses on recent technical innovations for conducting long‐term studies of i.v. drug self‐administration behavior in healthy, freely moving rats and mice. Included are protocols for construction, implantation, and maintenance of chronic indwelling jugular catheters, commentary on critical parameters, a troubleshooting guide, and anticipated results.
Intravenous Self‐Administration Techniques in Monkeys
Authors: Platt Donna M. , Carey Galen , Spealman Roger D.
Published: August 2005

Drug self‐administration is a procedure in which a subject performs a response, called an operant, that results in the delivery of a drug injection. This procedure is viewed as a relevant model for the study of human drug‐taking behavior. Drug self‐administration in primates has several characteristics that resemble drug‐taking behavior in humans, and drugs that are commonly abused by humans also typically maintain self‐administration behavior in monkeys. Drug self‐administration procedures allow for the study of a variety of drug properties. For instance, they are used to investigate the abuse potential of new compounds and to study the effects of candidate medications for the treatment of drug addiction. These procedures also can be used to study the process of drug reinforcement. This unit describes intravenous drug self‐administration in large primates, such as rhesus macaques, and smaller primates, such as squirrel monkeys.
Transgenic Mouse Colony Management
Authors: Conner David A.
Published: August 2005

This unit describes strategies and methods used to establish a colony of transgenic mice. Basic mating and genotyping strategies are introduced.
Modification and Production of BAC Transgenes
Authors: Jeong Yongsu , Epstein Douglas J.
Published: August 2005

Bacterial artificial chromosomes (BACs) are the vectors of choice for the construction of genomic DNA libraries and, as such, have proven instrumental in the generation of large‐scale physical maps; positional cloning projects; and the sequencing of human, mouse, and a plethora of other genomes. A number of methods have recently been developed to modify BAC DNA (e.g., insertion, deletion, substitution), making BACs even more useful for functional genomic research. This unit describes two protocols for BAC modification in E. coli, one that allows for specific changes at a given DNA sequence and another that is more suited for rapid and nonspecific integration of foreign DNA (such as a reporter cassette) into a BAC insert. In addition, a simple and reliable method for preparing BAC DNA for pronuclear microinjection is also provided.
Detecting Gene‐Gene Interaction in Linkage Analysis
Authors: Li Chun
Published: August 2005

Linkage analysis has been very successful in identifying genes for many Mendelian diseases, but has not enjoyed the same level of success for complex diseases. A major reason is that complex diseases are multifactorial, involving multiple genes and environmental factors. Linkage analysis is powerful for localizing disease genes with moderate marginal effects with most realistic sample sizes. Traditionally it has been used to search for a single disease locus at one time, and most implementations lack the power to detect genes with small marginal effect but moderate to strong interaction effect with other genes. Thus, methods for detecting gene‐gene interaction in linkage analysis are needed. A brief background on gene‐gene interaction in linkage analysis is given, with a review of two major approaches: two‐locus linkage analysis and interaction analysis. Three methods of interaction analysis are also reviewed: conditional linkage analysis, ordered subset analysis, and generalized estimating equations.
Microscopy and Image Analysis
Authors: McNamara George , Difilippantonio Michael J. , Ried Thomas
Published: August 2005

This unit provides an overview of light microscopy, including objectives, light sources, filters, film, and color photography for fluorescence microscopy and fluorescence in situ hybridization (FISH). Computerized image‐analysis systems currently used in clinical cytogenetics are also discussed.
The BAC Resource: Tools for Array CGH and FISH
Authors: Nowak Norma J. , Snijders Antoine M. , Conroy Jeffrey M. , Albertson Donna G.
Published: August 2005

Bacterial Artificial Chromosome (BAC) vector clones carrying human DNA were chosen as the intermediate templates for the sequencing of the human genome due to their inherent stability and fidelity to the genome sequence from which they were derived. In this unit, we describe a set of protocols for BAC‐based array comparative genomic hybridization (aCGH) that comprise the generation of targets for printing solutions onto glass slides, the subsequent hybridization steps, and CGH analysis of a test sample compared to a reference normal sample. The BAC clones through their sequence allow the extent and gene content of numerical aberrations to be delineated by aCGH, and also provide cytogeneticists with tools for subsequent validation or fine mapping studies.
Ten‐Color Immunophenotyping of Hematopoietic Cells
Authors: Wood Brent L.
Published: August 2005

Multicolor flow cytometry offers the unique ability to simultaneously assess and correlate multiple cellular properties at the single‐cell level in a timely and efficient manner. Principles necessary for the development and evaluation of 10‐color flow cytometry panels are discussed. The Basic Protocol outlines a simple and efficient method for the labeling of white blood cells with monoclonal antibodies directed against cell surface antigens. Alternate Protocol 1 incorporates the removal of plasma to allow the simultaneous assessment of surface light‐chain expression on B cell populations. Alternate Protocol 2 describes a general method for the simultaneous assessment of surface and cytoplasmic antigens using a combination of fixation followed by membrane permeabilization. The methods were developed in a clinical laboratory setting for the description of normal pathways of hematopoietic maturation and the efficient identification of neoplastic hematopoietic cell populations, but the general principles should also be suitable for other applications.
RNA and DNA Aptamers in Cytomics Analysis
Authors: Ulrich Henning , Martins Antonio Henrique B. , Pesquero João Bosco
Published: August 2005

Using systematic evolution of ligands by exponential enrichment (SELEX), RNA or DNA molecules are selected from a combinatorial oligonucleotide library by their ability to bind their targets, i.e., cell surface antigens, with affinity and specificity similar to that of monoclonal antibodies. The generation of these high‐affinity binders, also denominated aptamers, is carried out in vitro and does not involve animals. Therefore, aptamers can be developed against almost every molecule of biological importance, including toxins and nonimmunogenic targets, against which antibodies cannot be raised. The incorporation of modified pyrimidines resulting in nuclease‐resistant RNA aptamers makes them promising candidates for studying protein interactions in vitro and in vivo. DNA aptamers do not need modifications for most applications. The protocols in this unit can be used for the development of fluorescent‐tagged RNA or DNA aptamers for any cell surface protein in cytomics analysis.
Stem Cell Identification and Sorting Using the Hoechst 33342 Side Population (SP)
Authors: Goodell Margaret A.
Published: August 2005

This unit describes the use of Hoechst 33342 to identify and purify murine hematopoietic stem cells, the so‐called side population. Three properties of the dye contribute to the ability to distinguish stem cells in this way. Hoechst is a DNA‐binding dye. It has at least two binding modes that result in different spectral properties, allowing resolution of multiple populations by viewing fluorescence at two wavelengths simultaneously. The ability to discriminate SP cells is based on the differential efflux of the dye by a multi‐drug‐like transporter. Particular attention is given to the critical aspects of Hoechst concentration, cell concentration, staining time, and staining temperature.
Quantitative Fluorescence In Situ Hybridization (QFISH) of Telomere Lengths in Tissue and Cells
Authors: O'Sullivan Jacintha N. , Finley Jennifer C. , Risques Rosa‐ana , Shen Wen‐Tang , Gollahon Katherine A. , Rabinovitch Peter S.
Published: August 2005

Telomeres are repetitive DNA sequences at the end of each chromosome that provide stability and prevent end‐to‐end chromosome fusions. In order to understand mechanisms responsible for telomere shortening, it is necessary to develop methods for accurate telomere length measurement that can be applied to archival and fresh tissue and cells. This unit describes in situ–based quantitative fluorescence in situ hybridization (QFISH) protocols using a fluorescence‐conjugated telomere probe (peptide nucleic acid, PNA) that stains telomeres proportionally to their length. These protocols can be used on formalin‐fixed paraffin‐embedded tissue, lightly fixed tissue, cells isolated from tissue, cultured cells, and agar‐embedded cells. The basic protocol for QFISH staining is modified to achieve excellent QFISH staining for a variety of cell preparations. Image‐analysis techniques to quantitate average telomere lengths from tissues and isolated stained cells are also described.
Control System Design, Continuous‐Time
Authors: Ogata Katsuhiko
Published: September 2005

The sections in this article are

System Compensation

Root‐Locus Method

Frequency‐Response Method

Root‐Locus Approach to the Design of Control Systems

Frequency‐Response Approach to the Design of Control Systems

Comparison of Lead, Lag, Lag‐Lead Compensation

Multi‐Degrees‐of‐Freedom Control

Concluding Comments
Chaos, Bifurcations, and Their Control
Authors: Chen Guanrong
Published: September 2005

The sections in this article are

Nonlinear Dynamics

Chaos

Bifurcations

Controlling Chaos

Controlling Bifurcations

Anticontrol of Chaos
Convex Optimization
Authors: Sapatnekar Sachin S.
Published: September 2005

The sections in this article are

Definitions of Convexity

Convex Optimization

Related Techniques

Engineering Problems as Convex Optimization Problems

Conclusion
Multivariable Systems
Authors: Castañon David
Published: September 2005

The sections in this article are

Multivariable Linear Systems
Nonlinear Control Systems, Design Methods
Authors: Loria Antonio , Nijmeijer Henk
Published: September 2005

The sections in this article are

The Regulation Problem

Linear Time‐Invariant Systems

Feedback Linearization

Passivity‐Based Control

Control Under Model and Parameter Uncertainties

Third‐Order Feedback Linearizable Systems

Conclusion

Acknowledgments
Stability Theory, Asymptotic
Authors: Eren Halit , Lowe Alexander
Published: September 2005

The sections in this article are

Stability Criteria

Bounded‐Input–Bounded‐Output Stability

Asymptotic Stability

Routh–Hurwitz Criterion

Nyquist Criterion

The Root Locus

The Riccati Equation

Lyapunov Stability

Robust Stability

Exponential Stability
Stability Theory, Nonlinear
Authors: Khalil Hassan K. , Shaw Steven W.
Published: September 2005

The sections in this article are

Steady‐State Behavior

Stability of Equilibrium Points

Bifurcation Theory

Further Reading
Aerospace Expert Systems
Authors: Kornecki Andrew J. , Blanchard James W.
Published: September 2005

The sections in this article are

Artificial Intelligence—Concepts and Approaches

National Airspace System

Air Traffic Flow Management Operations

Intelligent Training

Expert Systems for Pilots

Expert Systems and Simulation in Other Aerospace Applications

Expert Systems in Aviation and Aerospace Systems

Future Trends
Air Traffic Control
Authors: Sridhar B. , Chatterji G. B.
Published: September 2005

The sections in this article are

Historical Development of the ATM System

Operations Within the ATM System

Future ATM Developments

Global ATM
Aircraft Computers
Authors: Satterthwaite Charles P.
Published: September 2005

The sections in this article are

Avionics

Aerospace

Man–Machine Systems

Aircraft Control And Computers

Real‐Time Systems
Aircraft Dynamics and Control
Authors: Hess Ronald A.
Published: September 2005

The sections in this article are

Background

Mathematical Description Of The Aircraft

The Laplace Transform And Transfer Function

Control‐System Architecture

Trajectory Optimization

Control‐System Design—A Classical Approach

Control‐System Design—Modern Approaches
Jet Transport Maintenance
Authors: Hessburg Jack , Reuter Richard , Ahl William
Published: September 2005

The sections in this article are

Failure

Failure Management

Air Carrier Maintenance Requirements

Scheduled Maintenance

Unscheduled Maintenance

The Maintenance Environment

Airplane System Design for Maintenance

Airplane Maintenance Design Trends

Maintenance Support

Technical Training for Maintenance

Electronic Performance Support Tools
Electronic Warfare
Authors: Spezio Anthony E. , Duckworth Alan N. , Klemm Francis J. , Moroz Stanley A. , Talley James M.
Published: September 2005

The sections in this article are

Electronic Warfare Time Line

The Electronic Warfare Environment

Electronic Warfare Functional Areas

Electronic Warfare Technical Areas
Missile Control
Authors: Yang Ciann‐Dong , Yang Chi‐Ching , Chen Hsin‐Yuan
Published: September 2005

The sections in this article are

Components of Missile Control Systems

Missile Aerodynamic Control

Missile Thrust Vector Control

Missile Control Configuration

Missile Control Strategy

Missile Autopilot Design
Radar Remote Sensing of Irregular Stratified Media
Authors: Bahar Ezekiel
Published: September 2005

The sections in this article are

Schelkunoff's Generalized Telegraphists' Equations for Bounded Irregular Waveguides and the Use of Local Mode Expansions

Generalized Telegraphists' Equations for Irregular Stratified Media with one or Two Half‐Spaces

Transformation of Maxwell's Equations

Iterative Solutions to the Generalized Telegraphists' Equations and Their Relationships to the Small Perturbation Solution and the Physical/Geometrical Solutions to Rough Surface Scattering

Full‐Wave Solutions for the Radar Cross Sections for Multiple‐Scale Rough Surfaces

Full‐Wave Solutions for Three Media Irregular Stratified Structures

Acknowledgments
Antenna Radiation Patterns
Authors: Chryssomallis Michael , Christodoulou Christos
Published: September 2005

The sections in this article are

Radiation from Antennas

Antenna Performance Measures

Polarization

Evaluation of Antenna Pattern and Directivity (General Case)
Antenna Theory
Authors: Stutzman Warren L. , Davis William A.
Published: September 2005

The sections in this article are

Fundamentals

Antenna Characteristics

Antenna Performance Measures
Radiowave Propagation Concepts
Authors: Levis Curt A.
Published: September 2005

The sections in this article are

The Influence of Frequency and Environment

Propagation Mechanisms and Models

Transmission Loss

Acknowledgment
Backscatter
Authors: Ufimtsev Pyotr Ya.
Published: September 2005

The sections in this article are

Quasi‐Static Scattering

Resonance Scattering

Quasi‐Optical Scattering

Backscattering Rcs Of Simple Shapes

Backscattering From Complex Objects And Stealth Problems
Conformal Antennas
Authors: Sengupta Dipak L.
Published: September 2005

The sections in this article are

Basic Antenna Elements

Conformal Antennas

Conformal Arrays
Directive Antennas
Authors: Alexeff Igor , Rader Mark , Kang Weng Lock
Published: September 2005

The sections in this article are
Helical Antennas
Authors: Adams Arlon T. , Lee Jay K.
Published: September 2005

The sections in this article are

Monofilar Helical Antenna

Multifilar Helix Antennas
Leaky‐Wave Antennas
Authors: Galli Alessandro , Frezza Fabrizio , Lampariello Paolo
Published: September 2005

The sections in this article are

Distinctive Features And Applications

Operation Principles

Design Techniques

Overview Of Specific Structures

Practical Considerations And Measurements
Loop Antennas
Authors: Siwiak Kazimierz
Published: September 2005

The sections in this article are

Analysis Of Loop Antennas

Loop Applications
Satellite Antennas
Authors: Dybdal R. B.
Published: September 2005

The sections in this article are

Space Segment Antennas

User Segment Antennas

Satellite Antenna Testing
Scanning Antennas
Authors: Hansen R. C.
Published: September 2005

The sections in this article are

Phased Array Basics

Scanning Techniques

Quantization Effects

Mutual Coupling Effects

Finite Arrays
Spiral Antennas
Authors: Mayes Paul E.
Published: September 2005

The sections in this article are

Spiral Antenna Geometry

History of Development

Theory of Operation

Experimental Data

Recent and Future Work
Ionosphere Characteristics
Authors: Goodman John M.
Published: September 2005

The sections in this article are

General Properties of the Ionosphere

The Continuity Equation and Equilibrium Processes

Description of the Ionospheric Layers

Diurnal Behavior of the Ionospheric Layers

Long‐Term Solar‐Activity Dependence of the Ionospheric Layers

Sporadic E

The High‐Latitude Ionosphere

Ionospheric Response to Solar Flares

The Ionospheric Storm

Ionospheric Current Systems

Ionospheric Models

Ionospheric Predictions

Fundamental Science Issues and Challenges in Ionospheric Research
Sky Wave Propagation at Medium and High Frequencies
Authors: Davies Kenneth
Published: September 2005

The sections in this article are

Spectrum Considerations

Propagation Characteristics

Vertical and Oblique Propagation

Ionospheric Models

Propagation on Medium Frequencies

Propagation on High Frequencies

Communications Disruptions

Conclusions
Superconductors: Processing of High‐

T
C

Bulk, Thin Film, and Wires
Authors: Subramanyam Guru , Boolchand Punit
Published: September 2005

The sections in this article are

Properties of High‐Temperature Superconductors

Processing of High‐Temperature Superconductors

Processing of Bulk Superconductors

Characterization of Bulk Superconductors

Processing of Hts Thin Films

Processing of Superconducting Wires and Tapes

Applications of High‐Temperature Superconductors
Superconducting Magnets, Quench Protection
Authors: Schultz Joel H.
Published: September 2005

The sections in this article are

Coil Protection Circuits

Quench Detection

Magnet Protection Criteria

Quench Propagation

Electrical Integrity

Case Histories
Superconductors, Cryogenic Stabilization
Authors: Sekulic D. P. , Edeskuty F. J.
Published: September 2005

The sections in this article are

Experience from Early Magnet Applications

Causes of Instabilities (Disturbances)

Methods of Stabilization

Advanced Stability and Thermal Management Problems for Superconductors

Thermophysical and Heat Data on Cryogens

Safety

Additional Reading
High‐Energy Physics Particle Detector Magnets
Authors: Green Michael A.
Published: September 2005

The sections in this article are

The Development of Detector Solenoids

The Defining Parameters for Thin Solenoids

Thin Detector Solenoid Design Criteria

Magnet Power Supply and Coil Quench Protection

Design Criteria for The Ends of a Detector Solenoid

Cryogenic Cooling of a Thin Detector Solenoid
HTS Film Growth
Authors: Char Kookrin , Matijasevic Vladimir
Published: September 2005

The sections in this article are

Materials

Thermodynamic Issues

Epitaxy

Film Growth Methods

Sputtering

Laser Ablation

Evaporation and Molecular Beam Epitaxy

Concluding Remarks
Squids
Authors: Fagaly Robert L.
Published: September 2005

The sections in this article are

The Josephson Effect

Squid Operation

Input Circuits

Refrigeration

Applications
Superconducting Fault Current Limiters
Authors: Salasoo Lembit , Boenig Heinrich J.
Published: September 2005

The sections in this article are

Electric Utility Grid Application

Quenching Types

Ferromagnetic Types

Semiconductor Types

Other Types

Superconductor Requirements

Cryogenics

Conclusion
Superconducting Cyclotrons and Compact Synchrotron Light Sources
Authors: Andrews David E. , Blosser Henry
Published: September 2005

The sections in this article are

Superconducting Cyclotrons

Applications and Characteristics of Synchrotron Radiation

Technical description of a Compact Synchrotron
Superconducting Filters and Passive Components
Authors: Talisa Salvador H.
Published: September 2005

The sections in this article are

High‐Temperature Superconducting Film Processing Technology

Passive Superconducting Microwave Device Fundamentals

High‐Temperature Superconducting Filters

High‐Temperature Superconducting Delay Lines

Cryogenic Packaging

Conclusion