Analysis of the origin of through-space proton NMR deshielding by selected organic functional groups

GIAO-HF and IGLO-DFT computations of isotropic magnetic shieldings were used to map the NMR shielding environments of small molecules exemplifying selected organic functional groups. Two different probes were employed: a methane molecule and NICS (nucleus-independent chemical shifts) based on computed absolute isotropic shieldings. The reason for the different results obtained using these two probes is perturbation of the wave function by the proximity of methane to the pi bond, as analyzed by the localized orbital contributions to the shieldings. [structure: see text]

Body and spirit: Religion, spirituality, and health among adolescents

Religion and spirituality are important in the lives of many adolescents. This article traces patterns of adolescent religious/spiritual belief and practice and summarizes theories about religious development as they pertain to this age group. Data are provided that explore possible relationships between religion and health-related behavior among adolescents. Much of this data shows that greater religiosity/spirituality may be associated with less involvement in high-risk behaviors and more involvement in health-promoting behaviors. Implications of these data are discussed as well as possible negative roles that religion may play in youths' lives. The doctor's role in approaching religion and spirituality with patients is controversial. Health care professionals should be prepared to discuss these issues with adolescents for whom they are important, especially with patients who are hospitalized. Yet, doctors should be sensitive to those adolescents who may not want to delve into spiritual/religious issues in a health care setting.

Ribosome biogenesis: stripping for AAAction?

Ribosomal subunits are assembled in the nucleolus before being transported to the cytoplasm. Recent work has identified both a protein that may play a key role in restructuring the large, 60S subunit prior to transport and factors that facilitate transport itself.

Protein transport: two translocons are better than one

The translocon is the gateway to the endoplasmic reticulum (ER). In yeast this is the Sec61p complex. However, new evidence suggests that a second translocon containing the Sec61p homolog Ssh1p provides important flexibility to the ER translocation machinery.

Hospitalization for ambulatory care-sensitive conditions: a method for comparative access and quality studies using routinely collected statistics

BACKGROUND

Appropriate and timely provision of ambulatory care is an important factor in maintaining population health and in avoiding unneccessary hospital use. This article describes conditions for which hospitalization rates have a strong and inverse relationship to access to high-quality ambulatory care.

METHODS

Three panels of Canadian physicians following different consensus techniques selected conditions for which the relative risk of hospitalization is inversely related to ambulatory care access.

PRINCIPAL FINDINGS

All panels identified asthma, angina pectoris, congestive heart failure, otitis media, gastric ulcer, pelvic inflammatory disease, malignant hypertension, and immunization-preventable infections as ambulatory care-sensitive admissions. These conditions strongly overlap with lists developed for similar purposes in the U.S. and England.

INTERPRETATION

Ambulatory care-sensitive conditions represent an intermediate health outcome. They are distinct from inappropriate hospitalizations. They may be useful for measuring the impact of health care policy, and for performance measurement or audit.

Conduction block in neuralgic amyotrophy

We describe two cases of neuralgic amyotrophy with electrophysiological evidence of conduction block across the lower trunk of the brachial plexus. Low-output impedance stimulation of the cervical spinal roots in combination with collision was used to accurately demonstrate the conduction block. Complete electrophysiological recovery of the conduction block occurred within 3 months. Early clinical and electrophysiological recovery in both patients suggests that, in some cases, demyelination may predominate early in the course of neuralgic amyotrophy.

When the perpetrator gets killed: effects of observing the death of a handgun user in a televised public service announcement

This study evaluates the cognitive effects of an anti-handgun violence public service announcement (PSA) on sixth-, seventh-, and eighth-grade students (N = 294). Participants were randomly assigned to a treatment group, which viewed a PSA depicting the death of an aggressive handgun user, or a comparison group, which viewed identical content except that the PSA showed no negative consequence for the handgun user. Logistic regression analysis, adjusting for race and gender, revealed that the treatment group was more likely to report negative expected outcomes for aggressively using a handgun and lower behavioral intentions to aggressively use a handgun compared with the comparison group. These findings suggest that observing handgun violence on television that depicts death as a negative physical consequence for the perpetrator may produce lower handgun-encouraging beliefs compared with observing no consequence for the perpetrator--the norm for most televised violence today.

Handshaking, gender, personality, and first impressions

Although people's handshakes are thought to reflect their personality and influence our first impressions of them, these relations have seldom been formally investigated. One hundred twelve participants had their hand shaken twice by 4 trained coders (2 men and 2 women) and completed 4 personality measures. The participants' handshakes were stable and consistent across time and coders. There were also gender differences on most of the handshaking characteristics. A firm handshake was related positively to extraversion and emotional expressiveness and negatively to shyness and neuroticism; it was also positively related to openness to experience, but only for women. Finally, handshake characteristics were related to the impressions of the participants formed by the coders. These results demonstrate that personality traits, assessed through self-report, can predict specific behaviors assessed by trained observers. The pattern of relations among openness, gender, handshaking, and first impressions suggests that a firm handshake may be an effective form of self-promotion for women.

The development of a post-baccalaureate certificate program in molecular diagnostics

A post-baccalaureate certificate program in diagnostic molecular sciences was created in 1995 by the Diagnostic Genetic Sciences Program in the School of Allied Health at the University of Connecticut. The required on-campus lecture and laboratory courses include basic laboratory techniques, health care issues, cell biology, immunology, human genetics, research, management, and molecular diagnostic techniques and laboratory in molecular diagnostics. These courses precede a 6-month, full-time practicum at an affiliated full-service molecular laboratory. The practicum includes amplification and blotting methods, a research project, and a choice of specialized electives including DNA sequencing, mutagenesis, in situ hybridization methods, or molecular diagnostic applications in microbiology. Graduates of the program are immediately eligible to sit for the National Credentialing Agency examination in molecular biology to obtain the credential Clinical Laboratory Specialist in Molecular Biology (CLSp(MB). This description of the University of Connecticut program may assist other laboratory science programs in creating similar curricula.

Nuclear export of yeast signal recognition particle lacking Srp54p by the Xpo1p/Crm1p NES-dependent pathway

BACKGROUND

The movement of macromolecules through the nuclear pores requires energy and transport receptors that bind both cargo and nuclear pores. Different molecules/complexes often require different transport receptors. The signal recognition particle (SRP) is a conserved cytosolic ribonucleoprotein that targets proteins to the endoplasmic reticulum. Previous studies have shown that the export of SRP RNA from the nucleus requires trans-acting factors and that SRP may be at least partly assembled in the nucleus, but little else is known about how it is assembled and exported into the cytoplasm.

RESULTS

Of the six proteins that constitute the yeast SRP, we found that all except Srp54p were imported into the nucleus. Four of these had nucleolar pools. The same four proteins are required for stability of the yeast SRP RNA scR1, suggesting that they assemble with the RNA in the nucleus to form a central core SRP. This core SRP was a competent export substrate. Of the remaining components, Sec65p entered the nucleus and was assembled onto the core particle there, whereas Srp54p was solely cytoplasmic. The export of SRP from the nucleus required the transport receptor Xpo1p/Crm1p and Yrb2p, both components of the pathway that exports leucine-rich nuclear export signal (NES)-containing proteins from the nucleus.

CONCLUSIONS

The SRP is assembled in the nucleus into a complex lacking only Srp54p. It is then exported through the NES pathway into the cytoplasm where Srp54p binds to it. This transport route for a ribonucleoprotein complex is so far unique in yeast.

Adolescents' sexual media diets

A model of how adolescents choose, interpret, and interact with the mass media is discussed in the context of sexual development. The Media Practice Model suggests that adolescents select and react to sexual media diets that speak to an emerging sense of themselves as sexual human beings. Relatively little is known about how the sexual content adolescents attend to in the media is interpreted or incorporated into their lives. Entertainment-education and media literacy are two strategies for increasing the possibility of healthy outcomes from adolescents' use of sexual media.

The maternal Xenopus beta-catenin signaling pathway, activated by frizzled homologs, induces goosecoid in a cell non-autonomous manner

In spite of abundant evidence that Wnts play essential roles in embryonic induction and patterning, little is known about the expression or activities of Wnt receptors during embryogenesis. The isolation and expression of two maternal Xenopus frizzled genes, Xfrizzled-1 and Xfrizzled-7, is described. It is also demonstrated that both can activate the Wnt/beta-catenin signaling pathway as monitored by the induction of specific target genes. Activation of the beta-Catenin pathway has previously been shown to be necessary and sufficient for specifying the dorsal axis of Xenopus. beta-Catenin is thought to work through the cell-autonomous induction of the homeobox genes siamois and twin, that in turn bind to and activate the promoter of another homeobox gene, goosecoid. However, it was found that the beta-catenin pathway regulated the expression of both endogenous goosecoid, and a goosecoid promoter construct, in a cell non-autonomous manner. These data demonstrate that maternal Frizzleds can activate the Wnt/beta-catenin pathway in Xenopus embryos, and that induction of a known downstream gene can occur in a cell non-autonomous manner.

Elongation arrest is a physiologically important function of signal recognition particle

Signal recognition particle (SRP) targets proteins for co-translational insertion through or into the endoplasmic reticulum membrane. Mammalian SRP slows nascent chain elongation by the ribosome during targeting in vitro. This 'elongation arrest' activity requires the SRP9/14 subunit of the particle and interactions of the C-terminus of SRP14. We have purified SRP from Saccharomyces cerevisiae and demonstrated that it too has elongation arrest activity. A yeast SRP containing Srp14p truncated at its C-terminus (delta C29) did not maintain elongation arrest, was substantially deficient in promoting translocation and interfered with targeting by wild-type SRP. In vivo, this mutation conferred a constitutive defect in the coupling of protein translation and translocation and temperature-sensitive growth, but only a slight defect in protein translocation. In combination, these data indicate that the primary defect in SRP delta C29 is in elongation arrest, and that this is a physiologically important and conserved function of eukaryotic SRP.

Handshaking, gender, personality, and first impressions

Although people's handshakes are thought to reflect their personality and influence our first impressions of them, these relations have seldom been formally investigated. One hundred twelve participants had their hand shaken twice by 4 trained coders (2 men and 2 women) and completed 4 personality measures. The participants' handshakes were stable and consistent across time and coders. There were also gender differences on most of the handshaking characteristics. A firm handshake was related positively to extraversion and emotional expressiveness and negatively to shyness and neuroticism; it was also positively related to openness to experience, but only for women. Finally, handshake characteristics were related to the impressions of the participants formed by the coders. These results demonstrate that personality traits, assessed through self-report, can predict specific behaviors assessed by trained observers. The pattern of relations among openness, gender, handshaking, and first impressions suggests that a firm handshake may be an effective form of self-promotion for women.

Cardiovascular responses during prolonged exercise at ventilatory threshold in boys and men

PURPOSE

The purpose of this study was to examine the cardiovascular responses during prolonged exercise in boys and men at an intensity set relative to ventilatory threshold (VT).

METHODS

Eight boys (10-13 yr) and 10 men (18-25 yr) completed an orientation trial, a maximal exercise test, and a 40-min submaximal exercise bout at an intensity equal to the VO2 at VT (approximately 64.5% VO2max).

RESULTS

Heart rate (HR) was higher and stroke volume (SV) was lower in the boys compared with the men (P < or = 0.05). From 10 to 40 min, HR significantly increased 9.5% and 13.6% and SV significantly decreased 8.8% and 11.6% in the boys and men, respectively. Despite the tendency for the changes in HR and SV to be greater in the men, the group-by-time interaction was not significant. Cardiac output was greater in the men (P < or = 0.05) but remained constant over time (P > 0.05). In men, mean arterial blood pressure was higher (P < or = 0.05) and decreased 4.2% over time. In boys, mean arterial blood pressure remained constant, which resulted in a significant group-by-time interaction. Total peripheral resistance (TPR) was significantly higher in the boys and remained constant over time (P > 0.05). From 0 to 40 min, the decrease in plasma volume was significantly greater in the men (-10.2%) than the boys (-5.7%) but was unrelated to the changes in SV in either group (P > 0.05).

CONCLUSION

In conclusion, the cardiovascular responses during prolonged exercise are similar in boys and men, although there is a tendency for the magnitude of cardiovascular drift to be greater in the men.

An algorithm for predicting proton nuclear magnetic resonance deshielding over a carbon-carbon double bond

Hydrogen nuclei located over a carbon-carbon double bond in a strong magnetic field experience NMR shielding effects that result from the magnetic anisotropy of the nearby double bond and various other intramolecular shielding effects. We have used GIAO, a subroutine in Gaussian 98, to calculate isotropic shielding values and to predict the proton NMR shielding increment for a simple model system: methane held in various orientations, positions, and distances over ethene. The average proton NMR shielding increments of several orientations of methane have been plotted versus the Cartesian coordinates of the methane protons relative to the center of ethene. A single empirical equation for predicting the NMR shielding experienced by protons over a carbon-carbon double bond has been developed from these data. The predictive capability of this equation has been validated by comparing the shielding increments for several alkenes calculated using our equation to the experimentally observed shielding increments. This equation predicts the NMR shielding effects more accurately than previous models that were based on fewer geometries of methane over ethene. In fact, deshielding is predicted by this equation for protons over the center and within about 3 A of a carbon-carbon double bond. This result is in sharp contrast to predictions made by the long-held McConnell "shielding cone" model found in nearly every textbook on NMR, but is consistent with experimental observations. The algorithm for predicting the (de)shielding increment for a proton over an alkene can be used in a spreadsheet on a PC or incorporated into software that estimates chemical shifts using additive substituent constants or a database of structures. In either application its use can substantially improve the accuracy of the estimated chemical shift of a proton in the vicinity of a carbon-carbon double bond, and thus assist in spectral assignments and in correct structure determination.

Mechanism and function of signal transduction by the Wnt/beta-catenin and Wnt/Ca2+ pathways

Communication between cells is often mediated by secreted signaling molecules that bind cell surface receptors and modulate the activity of specific intracellular effectors. The Wnt family of secreted glycoproteins is one group of signaling molecules that has been shown to control a variety of developmental processes including cell fate specification, cell proliferation, cell polarity and cell migration. In addition, mis-regulation of Wnt signaling can cause developmental defects and is implicated in the genesis of several human cancers. The importance of Wnt signaling in development and in clinical pathologies is underscored by the large number of primary research papers examining various aspects of Wnt signaling that have been published in the past several years. In this review, we will present a synopsis of current research with particular attention paid to molecular mechanism of Wnt signal transduction and how the mis-regulation of Wnt signaling leads to cancer.

Late traumatic intraocular lens extrusion after penetrating keratoplasty

BACKGROUND

Penetrating keratoplasty places a patient at risk for wound rupture from blunt trauma because the graft-host interface remains weakened for years after the surgery. Violent environments, contact sports, and strenuous activity put patients with compromised corneal structural integrity at high risk of traumatic injury.

CASE REPORT

This case report presents a 42-year-old penetrating keratoplasty patient with a history of homelessness, polysubstance abuse, and domestic violence. This patient experienced a ruptured globe at the graft-host junction secondary to a direct blow by a fist, which extruded the intraocular lens from the eye. After emergency wound closure, the graft continued to degrade until bullous keratopathy developed. With little visual recovery potential for this graft, a Gunderson conjunctival flap procedure was implemented to decrease chronic ocular pain.

CONCLUSIONS

After penetrating keratoplasty, patients should be periodically reminded of the susceptibility of the graft wound to injury from high-risk activity and violence. Constant use of protective eyewear should be recommended to corneal transplant recipients.

An outbreak of acute eosinophilic myositis attributed to human Sarcocystis parasitism

Seven members of a 15-man U.S. military team that had operated in rural Malaysia developed an acute illness consisting of fever, myalgias, bronchospasm, fleeting pruritic rashes, transient lymphadenopathy, and subcutaneous nodules associated with eosinophilia, elevated erythrocyte sedimentation rate, and elevated levels of muscle creatinine kinase. Sarcocysts of an unidentified Sarcocystis species were found in skeletal muscle biopsies of the index case. Albendazole ameliorated symptoms in the index case; however, his symptoms persisted for more than 5 years. Symptoms in 5 other men were mild to moderate and self-limited, and 1 team member with laboratory abnormalities was asymptomatic. Of 8 team members tested for antibody to Sarcocystis, 6 were positive; of 4 with the eosinophilic myositis syndrome who were tested, all were positive. We attribute this outbreak of eosinophilic myositis to accidental tissue parasitism by Sarcocystis.

Community-acquired methicillin-resistant Staphylococcus aureus in hospitalized adults and children without known risk factors

Community-acquired methicillin-resistant Staphylococcus aureus (MRSA) infections are not commonly recognized in healthy patients without predisposing risk. We performed a retrospective study of patients hospitalized with community-acquired MRSA infections from 1992 to 1996 in Honolulu to determine if community-acquired MRSA infections occurred in patients without known risk. Patients hospitalized within the previous 6 months or transferred from other hospitals or nursing homes were excluded. Epidemiological and clinical data were obtained from an inpatient chart review. Ten (71%) of 14 patients with community-acquired MRSA infection had no discernible characteristics of MRSA infections. Thirteen (93%) patients had skin or soft-tissue infections and one patient had MRSA pneumonia. Isolates from patients with MRSA infection were more likely to be susceptible to ciprofloxacin (P = .05), clindamycin (P = .03), and erythromycin (P = .01) than were those from MRSA-colonized patients. In our population, the majority of community-acquired MRSA infections occurred in previously healthy individuals without characteristics suggestive of MRSA transmission.

Failure to confirm the Rauscher and Shaw description of recovery of the Mozart effect

The Mozart effect is an increase in spatial reasoning scores detected immediately after listening to the first movement of a Mozart piano sonata. Rauscher and Shaw (1998) suggested that failure to produce a Mozart effect could arise from carryover effects of a spatial reasoning pretest which may interfere with the effect of listening to Mozart. They cited an unpublished study in which a verbal distractor was inserted between the pretest and listening condition, and the manipulation produced the recovery of a Mozart effect. This experiment attempted to confirm the unpublished study. 206 college students were exposed to one of three sequences, pretest-Verbal distractor material-Mozart, pretest-Mozart-Verbal distractor material, and pretest-Verbal distractor material. An immediate posttest indicated no significant difference on solution of paper folding and cutting items among the three groups. The results do not support Rauscher and Shaw (1998). Our negative results are consistent with prior failures in other laboratories to produce a Mozart effect.

XCtBP is a XTcf-3 co-repressor with roles throughout Xenopus development

XTcf-3 is an HMG box transcription factor that mediates Xenopus dorsal-ventral axis formation. As a Wnt pathway effector, XTcf-3 interacts with beta-catenin and activates the expression of the dorsal organizing gene siamois, while in the absence of beta-catenin, XTcf-3 functions as a transcriptional repressor. We show that XTcf-3 contains amino- and carboxy-terminal repressor domains and have identified a Xenopus member of the C-terminal Binding Protein family of transcriptional co-repressors (XCtBP) as the C-terminal co-repressor. We show that two XCtBP binding sites near the XTcf-3 carboxy-terminus are required for the interaction of XTcf-3 and XCtBP and for the transcriptional repression mediated by the XTcf-3 carboxy-terminal domain. By fusing the GAL4 activation domain to XCtBP we have generated an antimorphic protein, XCtBP/G4A, that activates siamois transcription through an interaction with endogenous XTcf-3. Ectopic expression of XCtBP/G4A demonstrates that XCtBP functions in the regulation of head and notochord development. Our data support a role for XCtBP as a co-repressor throughout Xenopus development and indicate that XCtBP/G4A will be a useful tool in determining how XCtBP functions in various developmental processes.