646 research outputs found
Disruption of the \u3ci\u3eprotein kinase N\u3c/i\u3e gene of \u3ci\u3eDrosophila melanogaster\u3c/i\u3e Results in the Recessive \u3ci\u3edelorean\u3c/i\u3e Allele (\u3ci\u3epkn\u3csup\u3edln\u3c/sup\u3e\u3c/i\u3e) With a Negative Impact on Wing Morphogenesis
We describe the delorean mutation of the Drosophila melanogaster protein kinase N gene (pkndln) with defects in wing morphology. Flies homozygous for the recessive pkndln allele have a composite wing phenotype that exhibits changes in relative position and shape of the wing blade as well as loss of specific vein and bristle structures. The pkndln allele is the result of a P-element insertion in the first intron of the pkn locus, and the delorean wing phenotype is contingent upon the interaction of insertion-bearing alleles in trans. The presence of the insertion results in production of a novel transcript that initiates from within the 3\u27 end of the P-element. The delorean-specific transcript is predicted to produce a wild-type PKN protein. The delorean phenotype is not the result of a reduction in pkn expression, as it could not be recreated using a variety of wing-specific drivers of pkn-RNAi expression. Rather, it is the presence of the delorean-specific transcript that correlates with the mutant phenotype. We consider the delorean wing phenotype to be due to a pairing-dependent, recessive mutation that behaves as a dosage-sensitive, gain of function. Our analysis of genetic interactions with basket and nemo reflects an involvement of pkn and Jun-terminal kinase signaling in common processes during wing differentiation and places PKN as a potential effector of Rho1’s involvement in the Jun-terminal kinase pathway. The delorean phenotype, with its associated defects in wing morphology, provides evidence of a role for PKN in adult morphogenetic processes
Degeneration and impaired regeneration of gray matter oligodendrocytes in amyotrophic lateral sclerosis.
Oligodendrocytes associate with axons to establish myelin and provide metabolic support to neurons. In the spinal cord of amyotrophic lateral sclerosis (ALS) mice, oligodendrocytes downregulate transporters that transfer glycolytic substrates to neurons and oligodendrocyte progenitors (NG2(+) cells) exhibit enhanced proliferation and differentiation, although the cause of these changes in oligodendroglia is unknown. We found extensive degeneration of gray matter oligodendrocytes in the spinal cord of SOD1 (G93A) ALS mice prior to disease onset. Although new oligodendrocytes were formed, they failed to mature, resulting in progressive demyelination. Oligodendrocyte dysfunction was also prevalent in human ALS, as gray matter demyelination and reactive changes in NG2(+) cells were observed in motor cortex and spinal cord of ALS patients. Selective removal of mutant SOD1 from oligodendroglia substantially delayed disease onset and prolonged survival in ALS mice, suggesting that ALS-linked genes enhance the vulnerability of motor neurons and accelerate disease by directly impairing the function of oligodendrocytes
Sexual behavior research on a Cohort of gay men, 1984–1990: Can we predict how men will respond to interventions?
In 1984, over 1000 gay and bisexual men volunteered to participate in both the Chicago Multicenter AIDS Cohort Study (MACS) and a companion psychosocial study, the Coping and Change Study (CCS). Participants in the semiannual Chicago MACS/CCS evaluations comprise the largest cohort of high-risk men under continuous medical, behavioral, and psychosocial observation. Chicago MACS/CCS researchers prospectively chart the sexual behavior change patterns of the cohort and relate those behavioral changes to psychosocial correlates and actual HIV infection risk. This report summarizes the behavioral natural history of the Chicago MACS/CCS cohort from 1984 to 1990, focusing on receptive anal sex practices and use patterns for alcohol and the most frequently used recreational drugs. As these are prospective observational and not controlled intervention studies, psychosocial correlates of sexual behavior change by members of the cohort are suggestive of factors influencing behavior change rather than indicative of causal relationships. However, the voluntary availability to participants in the Chicago MACS/CCS of HIV-1 antibody test results beginning in late 1985 provided the opportunity to examine whether demographic, psychosocial, or behavioral factors were indicators of sexual behavior change following disclosure and counseling about HIV-1 serostatus. Recommendations for promotion and maintenance of safer sexual behavior for the long run, and limitations in the generalizability of these findings to the much more diverse populations of men who have sex with other men conclude this article.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44099/1/10508_2005_Article_BF01541496.pd
Computational chemical analysis of unconjugated bilirubin anions and insights into pKa values clarification
The pKa, the negative logarithm of the acid dissociation equilibrium constant, of the carboxylic acid groups of unconjugated bilirubin in water is a discussed issue because there are quite different experimental values reported. Using quantum mechanical calculations we have studied the conformational behavior of unconjugated bilirubin species (in gas phase and in solution modeled implicitly and explicitly) to provide evidence that may clarify pKa values because of its pathophysiological relevance. Our results show that rotation of carboxylate group, which is not restricted, settles it in a suitable place to establish stronger interactions that stabilizes the monoanion and the dianion to be properly solvated, demonstrating that the rationalization used to justify the high pKa values of unconjugated bilirubin is inappropriate. Furthermore, low unconjugated bilirubin (UCB) pKa values were estimated from a linear regression analysis.Fil: Vega Hissi, Esteban Gabriel. Universidad Nacional de San Luis. Facultad de Quimica, Bioquimica y Farmacia. Departamento de Quimica; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico San Luis. Instituto Multidisciplinario de Investigaciones BiolĂłgicas de San Luis; ArgentinaFil: Estrada, Mario Rinaldo. Universidad Nacional de San Luis. Facultad de Quimica, Bioquimica y Farmacia. Departamento de Quimica; ArgentinaFil: Lavecchia, MartĂn JosĂ©. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico La Plata. Centro de QuĂmica Inorgánica; ArgentinaFil: Pis Diez, Reinaldo. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico La Plata. Centro de QuĂmica Inorgánica; Argentin
Amici Curiae Brief of the International Municipal Lawyers Association and Legal Scholars in Support of Defendants-Appellees in Portland Pipe Line Corporation, et al. v. City of South Portland, et al.
This brief to the Maine Supreme Judicial Court was filed in support of the City of South Portland by the Amici Curiae, including the International Municipal Lawyers Association and legal scholars, to provide the Court with a background on the role of local governments in land use planning, and to explain why the City of South Portland’s Clear Skies Ordinance falls easily within the City’s authority and was not preempted by state legislation.After studying the potential for bulk loading of crude oil within its boundaries, the City of South Portland concluded that the infrastructure requirements and environmental impacts of the activity posed a threat to public health and welfare and were incompatible with the community’s vision of itself for the future. The City therefore decided to enact the Clear Skies Ordinance, which prohibits the storing and handling of petroleum or petroleum products for the bulk loading of crude oil onto any marine tank vessel in specified zoning districts. Litigation followed, with plaintiffs arguing that the City lacked authority to enact the Ordinance and that, even if it had such authority in the first instance, that authority had been preempted by other state law. Defendants prevailed on summary judgment in the U.S. District Court for the District of Maine, and during the course of an appeal to the United States Court of Appeals for the First Circuit, the Circuit certified several questions to the Maine Supreme Judicial Court. This brief was filed in support of the City with regard to those certified questions.The brief begins by discussing how central the role of local governments is in making land use decisions, emphasizing the highly localized impacts of land use decisions for public health and welfare. It then describes the zoning mechanisms by which local governments exercise their land use power, and discusses why the zoning power is so important for protecting public health and environmental quality, and responding to the changing needs of communities.Next, the brief explains the legal underpinnings of the City of South Portland’s home rule authority. The Constitution of the State of Maine contains a broad grant of home rule authority that is further strengthened by a statutorily imposed rebuttable presumption of validity for exercises of that authority. Local exercises of zoning authority are consistent within this home rule grant, and the brief discusses why the Clear Skies Ordinance falls squarely within the local zoning power. Finally, the brief explains why the Ordinance has not been expressly or impliedly preempted by state law. For all of those reasons, the brief concludes that the City’s enactment of the Ordinance was valid in the first instance and should not be overturned
A prospective study of alcohol consumption and HIV acquisition among injection drug users
Estimate the effect of alcohol consumption on HIV acquisition while appropriately accounting for confounding by time-varying risk factors
Determinants of alcohol consumption in HIV-uninfected injection drug users
We assess the association between time fixed and time varying participant characteristics and subsequent alcohol consumption in 1,968 injection drug users (median age 37 years, 28% female, 90% African-American) followed semi-annually from 1988 to 2008. Median alcohol consumption was seven drinks per week at study entry (first and third quartile: 1, 26) with 36% reporting binge drinking. Alcohol consumption and binge drinking decreased over follow-up. Older individuals and women reported consuming fewer drinks per week. Higher typical alcohol consumption was reported by those participants who reported in the prior six months: non-injection cocaine use, injection drug use, having one or more sex partners, or among men, a same sex partner. Associations were generally similar for drinks per week and binge drinking. This study demonstrates that in a large urban cohort of persons with a history of injection drug use, risky drug use and sexual risk behavior are associated with subsequent alcohol consumption
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