Social Media,Political Expression,and Political Participation: Panel Analysis of Lagged and Concurrent Relationships

This article relies on U.S. 2‐wave panel data to examine the role of social media as a sphere for political expression and its effects on political participation. Informational uses of social media are expected to explain political expression on social media and to promote political participation. This study clarifies the effect of using social media for social interaction in fostering political expression and participation processes. Results indicate that social media news use has direct effects on offline political participation and indirect effects on offline and online political participation mediated via political expression. Furthermore, social media use for social interaction does not have direct influence in people's political engagement, but rather an indirect effect by means of citizens expressing themselves politically.     

Effects of the nonsteroidal aromatase inhibitor, fadrozole, on the sexual behavior of male cynomolgus monkeys (Macaca fascicularis)

In many vertebrates, castration and hormone replacement and, more recently, the use of aromatase inhibitors, have shown that male sexual activity is mediated by the aromatization of testosterone (T) to estradiol (E2). In macaques, however, the systemic administration of E2, either alone or in combination with androgen, failed either to maintain or to restore the sexual activity of castrated males. The present study examines the effects of administering the nonsteroidal aromatase inhibitor, Fadrozole, either alone or combined with E2, to castrated, T-treated male cynomolgus monkeys at a dose of 0.25 mg/kg/day. This dose inhibited by over 98% the conversion of T to E2 and the subsequent accumulation of the latter in hypothalamic cell nuclei. Castrated males bearing sc Silastic impants of T were each tested with an ovariectomized, E2-treated female partner before, during, and after being given minipumps delivering either Fadrozole or water (240 1-hr tests). Within 2 weeks, Fadrozole significantly reduced ejaculatory activity and male sexual motivation in the absence of changes in plasma T levels, which remained in the upper range for intact males. Additional estradiol treatment produced small but significant increases in ejaculations by three of the six males only, and measures of male sexual motivation remained unchanged (120 tests). The present results, which stand in contrast to our previous findings in macaques, support the view that aromatization of T is important for ejaculatory activity and sexual motivation in a male primate. They also suggest that exogenous E2, which reaches the brain from the systemic circulation, does not fully duplicate the behavioral effects of E2 produced locally in the brain by the aromatization of T.     

A method for predicting sequelae to meningitis.

Reviews medical and behavioral literature for concomitants to meningitis that might predict the likelihood of intellectual sequelae to the disease. Five variables were identified: (a) occurrence and controllability of seizures, (b) time lapse between onset of the illness and treatment, (c) length of hospitalization, (d) patient's age at time of illness, and (e) concentration of bacteria in the cerebrospinal fluid. These variables were used to form a 5-item checklist for rating meningitis patients at the time of dismissal from the hospital. The possibility that such early observations might relate to later development in a manner similar to the Apgar Scale, which is employed at birth, is discussed. It is concluded that physicians and behavioral scientists need to become more aware of intellectual sequelae to meningitis and the variables related to it. (13 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Diazepam treatment of early signs of exacerbation in schizophrenia

OBJECTIVE: Therapeutic intervention at the earliest phase of symptom exacerbation in schizophrenia is an important clinical need, but specific pharmacotherapeutic interventions for this phase of illness have not been established. This study examined diazepam efficacy for this phase of treatment. METHOD: A double-blind, randomized clinical trial with 53 schizophrenic patients compared diazepam with placebo (with fluphenazine treatment for a comparison group). Treatment was initiated at the earliest signs of exacerbation, and symptom progression was the dependent measure used to evaluate efficacy. RESULTS: Diazepam was statistically superior to placebo in preventing symptom progression and was comparable to fluphenazine. CONCLUSIONS: Efficacy data support the use of diazepam in treating prodromal and early warning signs of symptom exacerbation in schizophrenia. This therapeutic strategy may be especially important for patients who refuse antipsychotic drugs or as a supplemental approach in a treatment plan that emphasizes low-dose antipsychotic therapy.     

Mitogenic activity of purified capsular polysaccharide A from Bacteroides fragilis: differential stimulatory effect on mouse and rat lymphocytes in vitro

Bacteroides fragilis, a Gram-negative colonic bacterium, induces the formation of abscesses associated with intra-abdominal sepsis in humans. The singular ability of this organism to modulate abscess formation in experimental rodent models resides in the structurally distinct and ionically charged capsular polysaccharides A (PS A) and B (PS B). The regulation of abscess formation in animals is dependent on T lymphocytes. However, the manner in which PS A interacts with T cells remains unknown. We therefore tested the T cell stimulatory capacity of purified PS A on mouse and rat lymphocytes in cellular proliferation assays and found that the PS A molecule possesses mitogenic characteristics distinguishable from those of the polyclonal B cell activator LPS, the T cell mitogen Con A, and staphylococcal enterotoxin A superantigen. Further, PS A stimulated proliferation of normal mouse and rat lymphocytes differentially. Mouse B cells responded to PS A in a fashion that did not require exogenous APC function, while rat T lymphocyte responses to PS A required APC function derived from autologous or xenogenic feeder cells. Cellular depletion experiments showed that the CD4+ subset of rat spleen cells was the primary responder cell type to PS A in vitro. The differential stimulatory effects of PS A on mouse and rat lymphocytes may reflect its ability to stimulate different lymphocyte subsets in vivo through the activities of receptor/counter-receptor pairs present on responder lymphocytes and cognate APC.     

Rate of nitric oxide production by lower alveolar airways of human lungs

This report describes methods for measuring nitric oxide production by the lungs' lower alveolar airways (VNO), defined as those alveoli and bronchioles well perfused by the pulmonary circulation. Breath holding or vigorous rebreathing for 15-20 s minimizes removal of NO from the lower airways and results in a constant partial pressure of NO in the lower airways (PL). Then the amount of NO diffusing into the perfusing blood will be the pulmonary diffusing capacity for NO (DNO) multiplied by PL and by mass balance equals VNO, or VNO = DNO(PL). To measure PL, 10 normal subjects breath held for 20 s followed by exhalation at a constant flow rate of 0.83 +/- 0.14 (SD) l/s or rebreathed at 59 +/- 15 l/min for 20 s while NO was continuously measured at the mouth. DNO was estimated to equal five times the single-breath carbon monoxide diffusing capacity. By using breath holding, PL equaled 2.9 +/- 0.8 mmHg x 10(-6) and VNO equaled 0.39 +/- 0.12 microl/min. During rebreathing PL equaled 2.3 +/- 0.6 mmHg x 10(-6) and VNO equaled 0.29 +/- 0.11 microl/min. Measurements of NO at the mouth during rapid, constant exhalation after breath holding for 20 s or during rebreathing provide reproducible methods for measuring VNO in humans.     

Restructuring Medicare for the next century: what will beneficiaries really need?

Medicare coverage falls short of its original mandate of access to modern medicine and protection against the high costs of medical care. These shortfalls destabilize both health outcomes and the economic viability of older adults and their families. Our proposed revisions would promote, rather than discourage, optimal care for beneficiaries. By replacing incentives for fragmented, episodic care with an orientation toward functional status, care management, and integration with long-term care, we can make an invaluable investment in a successfully aging society.     

Identification of quantitative trait loci governing arthritis severity and humoral responses in the murine model of Lyme disease

A spectrum of disease severity has been observed in patients with Lyme disease, with approximately 60% of untreated individuals developing arthritis. The murine model of Lyme disease has provided strong evidence that the genetic composition of the host influences the severity of arthritis following infection with Borrelia burgdorferi: infected C3H mice develop severe arthritis while infected C57BL/6N mice develop mild arthritis. Regions of the mouse genome controlling arthritis severity and humoral responses during B. burgdorferi infection were identified in the F2 intercross generation of C3H/HeNCr and C57BL/6NCr mice. Rear ankle swelling measurements identified quantitative trait loci (QTL) on chromosomes 4 and 5, while histopathological scoring identified QTL on a unique region of chromosome 5 and on chromosome 11. The identification of QTL unique for ankle swelling or histopathological severity suggests that processes under distinct genetic control are responsible for these two manifestations of Lyme arthritis. Additional QTL that control the levels of circulating Igs induced by B. burgdorferi infection were identified on chromosomes 6, 9, 11, 12, and 17. Interestingly, the magnitude of the humoral response was not correlated with the severity of arthritis in infected F2 mice. This work defines several genetic loci that regulate either the severity of arthritis or the magnitude of humoral responses to B. burgdorferi infection in mice, with implications toward understanding the host-pathogen interactions involved in disease development.     

Uptake of seven myocardial tracers during increased myocardial blood flow by dobutamine infusion

RATIONALE AND OBJECTIVES: Direct comparison of myocardial perfusion tracers has been made difficult by variability in experimental models, and by a virtual absence of data comparing tracer uptake to myocardial blood flow under conditions of increased myocardial oxygen consumption, similar to what occurs with dynamic exercise. METHODS: Tracer uptake versus myocardial blood flow was evaluated for thallium-201 (201TI) and six technetium-99m (99mTc) myocardial-imaging agents in 24 open-chest canines with an occluded left-anterior descending coronary artery during dobutamine infusion. Data were fitted to the exponential model y = ax(1 - exp[-PSc/x]), where y is the tissue tracer/g normalized to normal (activity at 1 mL/minute/g) and x is the blood flow measured by the radioactive microsphere method. RESULTS: With dobutamine, myocardial tracer uptake was linear across a wide range of ischemic and hyperemic flows for each tracer. Based on the permeability surface area product, 201TI and 99mTc Q3 provided the best tracer estimate of myocardial blood flow (5.30+/-0.86 mL/minute/g, r = 0.91; 5.46+/-0.58 mL/minute/g, r = 0.94, respectively). Correlation coefficient (r) values for other tracers studied were 99mTc Q4 (r =0.93), 99mTc Q12 (r = 0.93), 99mTc sestamibi (r = 0.90), 99mTc tetrofosmin (r = 0.96), and 99mTc-N-Noet (r = 0.82). CONCLUSIONS: Of the 99mTc tracers examined under conditions of dobutamine-altered myocardial contractility, the myocardial uptake properties of 99mTc Q3 were most similar to those of 201TI.