Dopamine D 4 Receptor-Deficient Mice Display Cortical Hyperexcitability

The dopamine D(4) receptor (D(4)R) is predominantly expressed in the frontal cortex (FC), a brain region that receives dense input from midbrain dopamine (DA) neurons and is associated with cognitive and emotional processes. However, the physiological significance of this dopamine receptor subtype has been difficult to explore because of the slow development of D(4)R agonists and antagonists the selectivity and efficacy of which have been rigorously demonstrated in vivo. We have attempted to overcome this limitation by taking a multidimensional approach to the characterization of mice completely deficient in this receptor subtype. Electrophysiological current and voltage-clamp recordings were performed in cortical pyramidal neurons from wild-type and D(4)R-deficient mice. The frequency of spontaneous synaptic activity and the frequency and duration of paroxysmal discharges induced by epileptogenic agents were increased in mutant mice. Enhanced synaptic activity was also observed in brain slices of wild-type mice incubated in the presence of the selective D(4)R antagonist PNU-101387G. Consistent with greater electrophysiological activity, nerve terminal glutamate density associated with asymmetrical synaptic contacts within layer VI of the motor cortex was reduced in mutant neurons. Taken together, these results suggest that the D(4)R can function as an inhibitory modulator of glutamate activity in the FC.Fil: Rubinstein, Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Cepeda, Carlos. University of California at Los Angeles; Estados UnidosFil: Hurst, Raymond S.. University of California at Los Angeles; Estados UnidosFil: Flores Hernandez, Jorge. University of California at Los Angeles; Estados UnidosFil: Ariano, Marjorie A.. The Chicago Medical School; Estados UnidosFil: Falzone, Tomas Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; ArgentinaFil: Kozell, Laura B.. Oregon Health Sciences University; Estados UnidosFil: Meshul, Charles K.. Oregon Health Sciences University; Estados UnidosFil: Bunzow, James R.. Oregon Health Sciences University; Estados UnidosFil: Low, Malcolm J.. Oregon Health Sciences University; Estados UnidosFil: Levine, Michael S.. University of California at Los Angeles; Estados UnidosFil: Grandy, David K.. Oregon Health Sciences University; Estados Unido

Concept of Operations Evaluation for Mitigating Space Flight-Relevant Medical Issues in a Planetary Habitat

Introduction: Analogue environments assist the NASA Human Research Program (HRP) in developing capabilities to mitigate high risk issues to crew health and performance for space exploration. The Habitat Demonstration Unit (HDU) is an analogue habitat used to assess space-related products for planetary missions. The Exploration Medical Capability (ExMC) element at the NASA Johnson Space Center (JSC) was tasked with developing planetary-relevant medical scenarios to evaluate the concept of operations for mitigating medical issues in such an environment. Methods: Two medical scenarios were conducted within the simulated planetary habitat with the crew executing two space flight-relevant procedures: Eye Examination with a corneal injury and Skin Laceration. Remote guidance for the crew was provided by a flight surgeon (FS) stationed at a console outside of the habitat. Audio and video data were collected to capture the communication between the crew and the FS, as well as the movements of the crew executing the procedures. Questionnaire data regarding procedure content and remote guidance performance also were collected from the crew immediately after the sessions. Results: Preliminary review of the audio, video, and questionnaire data from the two scenarios conducted within the HDU indicate that remote guidance techniques from an FS on console can help crew members within a planetary habitat mitigate planetary-relevant medical issues. The content and format of the procedures were considered concise and intuitive, respectively. Discussion: Overall, the preliminary data from the evaluation suggest that use of remote guidance techniques by a FS can help HDU crew execute space exploration-relevant medical procedures within a habitat relevant to planetary missions, however further evaluations will be needed to implement this strategy into the complete concept of operations for conducting general space medicine within similar environment

Electron affinity of Li: A state-selective measurement

We have investigated the threshold of photodetachment of Li^- leading to the formation of the residual Li atom in the $2p ^2P$ state. The excited residual atom was selectively photoionized via an intermediate Rydberg state and the resulting Li^+ ion was detected. A collinear laser-ion beam geometry enabled both high resolution and sensitivity to be attained. We have demonstrated the potential of this state selective photodetachment spectroscopic method by improving the accuracy of Li electron affinity measurements an order of magnitude. From a fit to the Wigner law in the threshold region, we obtained a Li electron affinity of 0.618 049(20) eV.Comment: 5 pages,6 figures,22 reference

Xenotransplantation: A historical–ethical account of viewpoints

Formal clinical trials of pig-to-human organ transplant—known as xenotransplantation—may begin this decade, with the first trials likely to consist of either adult renal transplants or pediatric cardiac transplant patients. Xenotransplantation as a systematic scientific study only reaches back to the latter half of the 20th century, with episodic xenotransplantation events occurring prior to that. As the science of xenotransplantation has progressed in the 20th and 21st centuries, the public's knowledge of the potential therapy has also increased. With this, there have been shifting ethical stances toward xenotransplantation in key areas, such as religious and public viewpoints towards xenotransplantation, animal rights, and public health concerns. This review provides a historical–ethical account of xenotransplantation and details if or how viewpoints have shifted over time

St. Catherines period mortuary complex

p. 272-341 : ill., 1 map ; 26 cm.Includes bibliographical references (p. 340-341)."The results of archaeological excavations of two St. Catherines period burial mounds - Marys Mound and Johns Mound - by field crews from the University of Georgia and the American Museum of Natural History are presented. Analysis of the ceramics recovered from the two mortuary localities suggests that both mounds were constructed during the terminal phase of the St. Catherines period, probably during the late twelfth or early thirteenth century A.D. Study of the human skeletal remains suggests that these people were physically robust and enjoyed good health, both skeletal and dental. Analysis of nonhuman skeletal remains shows that most identified taxa are present on St. Catherines Island today. In addition, the presence of the domestic pig, Sus scrofa, in association with one iterment from Johns Mound, points to historic (Altahama) period use of this locality. Thin-section analysis of whole clams (Mercenaria mercenaria) from both sites indicates that time of harvesting or death for all specimens falls within 'late fall' to 'late spring' (November to May)"--P. 273

Equity in health care financing: The case of Malaysia

Background: Equitable financing is a key objective of health care systems. Its importance is evidenced in policy documents, policy statements, the work of health economists and policy analysts. The conventional categorisations of finance sources for health care are taxation, social health insurance, private health insurance and out-of-pocket payments. There are nonetheless increasing variations in the finance sources used to fund health care. An understanding of the equity implications would help policy makers in achieving equitable financing. Objective: The primary purpose of this paper was to comprehensively assess the equity of health care financing in Malaysia, which represents a new country context for the quantitative techniques used. The paper evaluated each of the five financing sources (direct taxes, indirect taxes, contributions to Employee Provident Fund and Social Security Organization, private insurance and out-of-pocket payments) independently, and subsequently by combined the financing sources to evaluate the whole financing system. Methods: Cross-sectional analyses were performed on the Household Expenditure Survey Malaysia 1998/99, using Stata statistical software package. In order to assess inequality, progressivity of each finance sources and the whole financing system was measured by Kakwani's progressivity index. Results: Results showed that Malaysia's predominantly tax-financed system was slightly progressive with a Kakwani's progressivity index of 0.186. The net progressive effect was produced by four progressive finance sources (in the decreasing order of direct taxes, private insurance premiums, out-of-pocket payments, contributions to EPF and SOCSO) and a regressive finance source (indirect taxes). Conclusion: Malaysia's two tier health system, of a heavily subsidised public sector and a user charged private sector, has produced a progressive health financing system. The case of Malaysia exemplifies that policy makers can gain an in depth understanding of the equity impact, in order to help shape health financing strategies for the nation

Transient Midventricular Ballooning Syndrome A New Variant

We describe a new variant of transient left ventricular (LV) ballooning in North American Caucasian patients in which only the midventricle is affected. The patients described in this case series initially presented with emotional or physical stress and had similarities to transient apical ballooning syndrome; however, this variant is unique in that the transient ballooning involves the midventricle with hypercontractility of the apical and basal segments. The presentation, clinical features, and transient nature of the reported cases in this series are similar to transient LV apical ballooning and suggest a shared pathophysiologic etiology. Sparing of the apical segment with involvement of midventricle only supports etiologies not related to an epicardial coronary artery distribution. Although the pathophysiologic mechanism of the transient ventricular ballooning syndromes and other cases of catecholamine-associated transient ventricular dysfunction are not well understood, the emergence of this new variant raises further questions in the understanding of the “brain-heart” relationship

New evidence on housing wealth and consumption channels

This paper provides new evidence on the effect of housing wealth on consumption by focusing on the impact of home-equity extraction. We develop a household consumption decision model to illustrate the differential effect of home-equity extraction, relative to net home equity, on consumption. The home-equity extraction channel is also shown to vary with household-level borrowing constraints. Based on U.S. household survey data and an instrumental-variables approach, our empirical results validate model predictions. We find that the marginal propensity to consume is two times higher for the home-equity extraction channel relative to the conventional housing wealth effect. The consumption effect of home-equity extraction is more than 2.5 times greater for liquidity-constrained households than for unconstrained households. These results are even more pronounced in the case of durable goods consumption for constrained borrowers