The balance between stress and personal capital during pregnancy and the relationship with adverse obstetric outcomes: findings from the 2007 Los Angeles Mommy and Baby (LAMB) study

Stress during pregnancy is a salient risk factor for adverse obstetric outcomes. Personal capital during pregnancy, defined as internal and social resources that help women cope with or decrease their exposure to stress, may reduce the risk of poor obstetric outcomes. Using data from the 2007 Los Angeles Mommy and Baby study (N?=?3,353), we examined the relationships between the balance of stress and personal capital during pregnancy, or the stress-to-capital ratio (SCR), and adverse obstetric outcomes (i.e., pregnancy complications, preterm birth (PTB), low birth weight (LBW), and small for gestational age (SGA)). Women with a higher SCR (i.e., greater stress relative to personal capital during pregnancy) were significantly more likely to experience at least one pregnancy complication, PTB, and lower gestational age, but not LBW or SGA. Accounting for pregnancy complications completely mediated the association between the SCR and PTB. Our findings indicate that experiencing greater stress relative to personal capital during pregnancy is associated with an increased risk for pregnancy complications, PTB, and lower gestational age and that pregnancy complications may be a mechanism by which the SCR is related to adverse obstetric outcomes.     

Challenges for Teaching Injury Prevention in a Juvenile Detention Center

This case study explored the injury related experiences and perceptions of youth in detention and the delivery of first aid education in youth detention contexts. It aimed to develop an understanding of how a mainstream injury prevention intervention could be modified for youth detention populations. Teacher and student reactions to the program were examined and injury checklists, focus groups, and staff interviews were conducted. Analysis revealed serious injuries related to criminal behaviors, violence, dangerous driving, and substance use. Recommendations for youth detention interventions include lesson flexibility, discussions, role-plays, visual materials, peer support strategies, student-teacher relationships, and positive reinforcement.     

Natural micropolymorphism in human leukocyte antigens provides a basis for genetic control of antigen recognition

Human leukocyte antigen (HLA) gene polymorphism plays a critical role in protective immunity, disease susceptibility, autoimmunity, and drug hypersensitivity, yet the basis of how HLA polymorphism influences T cell receptor (TCR) recognition is unclear. We examined how a natural micropolymorphism in HLA-B44, an important and large HLA allelic family, affected antigen recognition. T cell–mediated immunity to an Epstein-Barr virus determinant (EENLLDFVRF) is enhanced when HLA-B*4405 was the presenting allotype compared with HLA-B*4402 or HLA-B*4403, each of which differ by just one amino acid. The micropolymorphism in these HLA-B44 allotypes altered the mode of binding and dynamics of the bound viral epitope. The structure of the TCR–HLA-B*4405^EENLLDFVRF complex revealed that peptide flexibility was a critical parameter in enabling preferential engagement with HLA-B*4405 in comparison to HLA-B*4402/03. Accordingly, major histocompatibility complex (MHC) polymorphism can alter the dynamics of the peptide-MHC landscape, resulting in fine-tuning of T cell responses between closely related allotypes.     

Reading depends on writing, in Chinese

Language development entails four fundamental and interactive abilities: listening, speaking, reading, and writing. Over the past four decades, a large body of evidence has indicated that reading acquisition is strongly associated with a child's listening skills, particularly the child's sensitivity to phonological structures of spoken language. Furthermore, it has been hypothesized that the close relationship between reading and listening is manifested universally across languages and that behavioral remediation using strategies addressing phonological awareness alleviates reading difficulties in dyslexics. The prevailing view of the central role of phonological awareness in reading development is largely based on studies using Western (alphabetic) languages, which are based on phonology. The Chinese language provides a unique medium for testing this notion, because logographic characters in Chinese are based on meaning rather than phonology. Here we show that the ability to read Chinese is strongly related to a child's writing skills and that the relationship between phonological awareness and Chinese reading is much weaker than that in reports regarding alphabetic languages. We propose that the role of logograph writing in reading development is mediated by two possibly interacting mechanisms. The first is orthographic awareness, which facilitates the development of coherent, effective links among visual symbols, phonology, and semantics; the second involves the establishment of motor programs that lead to the formation of long-term motor memories of Chinese characters. These findings yield a unique insight into how cognitive systems responsible for reading development and reading disability interact, and they challenge the prominent phonological awareness view.     

Peptide-induced nasal tolerance for a mycobacterial heat shock protein 60 T cell epitope in rats suppresses both adjuvant arthritis and nonmicrobially induced experimental arthritis

Adjuvant arthritis (AA) can be induced in Lewis rats by immunization with mycobacterial antigens. Passive transfer of a T cell clone recognizing the 180–188 amino acid sequence in mycobacterial heat shock protein 60 (hsp60) was found to induce AA. In the present study, we investigated whether tolerance was obtained for this AA-associated T cell epitope after intranasal or s.c. administration of a peptide containing this epitope. Two 15-mer peptides containing the mycobacterial hsp60 sequences 176–190 and 211–225 were used; 176–190 contained the T cell epitope 180–188, which was recognized by the arthritogenic T cell clone A2b and was the immunodominant hsp60 T cell epitope after induction of AA, and 211–225 contained a T cell epitope that was recognized both after induction of arthritis with whole Mycobacterium tuberculosis and after immunization with mycobacterial hsp60. In rats treated intranasally or subcutaneously with 176–190 and immunized with mycobacterial hsp60, proliferative responses to 176–190 were reduced. Proliferative responses to 211–225 and to whole mycobacterial hsp60 were not affected. AA was inhibited intranasally in the 176–190-treated rats but not in the 211–225-treated rats. Moreover, intranasal 176–190 led to similar arthritis-protective effects in a nonmicrobially induced experimental arthritis (avridine-induced arthritis). Therefore, tolerance for a disease-triggering, microbial cartilage-mimicking epitope may cause resistance to arthritis irrespective of the actual trigger leading to development of the disease.     

Identification of mammalian blood meals in mosquitoes by a multiplexed polymerase chain reaction targeting cytochrome B

To date, no polymerase chain reaction diagnostic technique exists to directly identify mammalian blood meals from mosquitoes by sized DNA fragments following agarose gel electrophoresis. We have developed a vertebrate-specific multiplexed primer set based on mitochondrial cytochrome b to identify the mammalian blood hosts of field-collected mosquitoes. Although designed for the study of African malaria vectors, the application of this tool is not restricted to this disease system. Validation of this diagnostic technique on dried anopheline and culicine field specimens collected in Zambia and Mali demonstrated that blood meals could be identified 2-7 months after collection. Time course experiments showed that host DNA was detectable in frozen mosquito abdomens 24-30 hours post-feeding. Additionally, multiple blood meals from different mammals could be detected in a single mosquito. This diagnostic assay will be a valuable tool for identifying the blood meals of field-collected mosquitoes where people and alternative mammal hosts are present.