Regional differences in matrix formation in the healing flexor tendon

In 20 white leghorn chickens, the effect of proximity (proximal vs. distal) to the repair site and the effect of sheath excision versus sheath repair on biochemical matrix formation in the healing zone 2 flexor tendon were studied. In 14 animals, the profundus tendon of the long toe on both feet was lacerated and repaired in zone 2. In the right foot, the sheath was repaired, and on the left foot, the sheath was excised. Segments proximal and distal to the laceration site were studied at six weeks postrepair compared to control segments. Sheath excision versus sheath repair had no effect on the net matrix formation of the healing flexor tendon. A higher DNA content and lower hydroxyproline and hexosamine contents were present in the healing tendons, indicating the healing process was not complete at six weeks. Sheath excision versus sheath repair had no effect on net matrix formation in the healing tendon. There is no difference in DNA content or glycosaminoglycan content in the proximal versus distal segments. There was a significantly greater net hydroxyproline content in the proximal segment versus the distal segment of the healing tendon, which was not present in similar control segments. These results support the concept that the zone 2 flexor tendon does not respond to injury as a homogeneous structure.     

Driving impairments in teens and adults with attention-deficit/hyperactivity disorder.

Available research provides compelling evidence that ADHD is associated with significantly increased risks for various adverse outcomes while driving, including increased traffic citations (particularly speeding), motor vehicle crashes for which the driver is at fault, repeated crash occurrences,and more severe crashes as determined from dollar damage and likelihood of bodily injuries from the crash. Not surprisingly, teens and adults with ADHD are more likely to have their licenses suspended and even fully revoked. Research further suggests that these driving risks cannot be accounted for by the comorbid disorders likely to be associated with ADHD, such as ODD, conduct disorder (CD), depression, or anxiety, or by lower than normal levels of intelligence.Recent attempts to study the processes or mechanisms involved in driving in adults with ADHD offer some explanation of how the disorder conveys such increased risks. Driving can be conceptualized usefully as involving at least three or more dimensions or levels, including basic cognitive abilities necessary for driving (operational), actual skills for maneuvering the vehicle in traffic (tactical), and the more executive, goal-directed aspects of driving(strategic). The findings of studies indicate that ADHD interferes with the basic operational components of driving by means of the impairments it produces in attention, resistance to distraction, response inhibition, slower and more variable reaction time, and the capacity to follow rules that may compete with ongoing sensory information. Accumulating evidence also points to a problem in the tactical level of driving, such that those with ADHDrate themselves and are rated by others as employing less safe driving habits during their normal operation of a vehicle than are adults in community control groups. Although this has been more elusive to demonstrate through the use of simple laboratory-based driving simulators. more modern virtual reality driving platforms offer greater promise in providing more realistic appraisals of driving performance and thus more direct evidence of the problems that occur at the tactical level from the disorder. Research has not examined the impact of ADHD at the higher strategic level or goal-directed aspects of driving. But given the mounting evidence that ADHD adversely affects executive functioning in adults, the author and colleagues anticipate that this level also will be found to be impaired in adults with ADHD. Indeed,it recently has been shown that adults with ADHD overestimate their driving abilities relative to normal adults, a problem that likely can be ascribed to more limited self-awareness and related meta-cognitive abilities for self-evaluation arising from the disorder.Although further research on the driving problems posed by ADHD is in order, sufficient evidence exists to warrant focus on possible treatments that may serve to improve these driving problems and reduce the risk for these adverse outcomes. High on the list of such treatments deserving further research and clinical attention is the use of stimulant medication. The more recent noradrenergic reuptake inhibitor. atomoxetine, also may have some promise in this regard. Studies are underway in the author's driving laboratory to see if this is the case. Meanwhile, adults with ADHD and parents of teens with ADHD should be advised about these heightened risks and encouraged to take steps that may reduce them, including the consideration of more graduated licensing for adolescents with ADHD and the possible use of stimulant medication in teens and adults with ADHD while they are operating a motor vehicle.     

Comparison of conversation, freeplay, and story generation as methods of language sample elicitation.

The spontaneous language sample forms an important part of the language evaluation protocol (M. Dunn, J. Flax, M. Sliwinski, and D. Aram, 1996; J. L. Evans and H. K. Craig, 1992; L. E. Evans and J. Miller, 1999) because of the limitations of standardized language tests and their unavailability in certain languages, such as Afrikaans. This study examined 3 methods of language elicitation, namely conversation (CV), freeplay (FP), and story generation (SG), on the following 5 measures to determine which method is best for clinical practice: number of utterances, variety of syntactic structures, mean length of the utterance (MLU), number of syntactic errors, and proportion of complex syntactic utterances as elicited from ten 5-year-old, Afrikaans-speaking boys. FP elicited significantly more utterances than did SG but elicited a smaller proportion of complex syntactic structures than did CV and SG. Furthermore, SG elicited longer utterances than did CV or FP. It is recommended that SG be used in clinical practice with 5-year-olds if the clinician wishes to observe maximum behavior. Where typical behavior is to be evaluated, the clinician can select a language elicitation method that best suits the client's personality and communication style, bearing in mind that FP does elicit a larger language sample.     

Trends in Labor Induction in the United States: Is It True That What Goes Up Must Come Down?

Commentary on: Zhang J, Yancey MK, Henderson CE. U.S. national trends in labor induction, 1989–1998. J Reprod Med 2002;47:120–124.
MacDorman MF, Mathews TJ, Martin JA, Malloy MH. Trends and characteristics of induced labour in the United States, 1989–98. Paediatr Perinat Epidemiol 2002;16:263–273.
Kozak LJ, Weeks JD. U.S. trends in obstetric procedures, 1990–2000. Birth 2002;29:157–161. Abstract: Three recent studies examined the national trend in labor induction in the United States. All show a doubling in the rate of induction during the 1990s, although vital statistics data show a consistently higher trend than that obtained from national hospital discharge data. Neither data source adequately documents the full range of indications for induction, its timing, hospital staffing considerations, and other factors that may play a role. Although rates of induction of labor may be leveling off, despite a lack of scientific evidence for its widespread use, rates are likely to remain at current levels for the next few years.     

Structure of the BoLA-DRB3 gene and promoter.

The cattle major histocompatibility complex (MHC) class II DR gene product is a heterodimer encoded by the BoLA-DRA and -DRB3 genes. Several groups have isolated cDNA and genomic clones for these genes, but their full genomic organization has not been described. We used a combination of long-range polymerase chain reaction (PCR), cloning and sequencing to define the organization of the DRB3 gene on existing genomic clones and in genomic DNA. We estimate the size of the coding region to be 11.4 kbp. Sequencing of full-length PCR clones from two different haplotypes confirmed that they carried complete DRB3 genes and allowed the design of probes and primers to isolate and characterize the DRB3 promoter and 3' end. Fragments carrying the 5' end of the DRB3 gene and its promoter were identified on bacterial artificial chromosome (BAC) clones carrying the BoLA-DR genes. A 10-kbp promoter fragment was subcloned from one clone and a 1.7-kbp region including exon 1 and the promoter was sequenced. A 3-kbp fragment encoding exons 4-6 and the entire 3' untranslated region of the DRB3 gene was isolated from lambda clone A1 and sequenced. This provides us with improved characterization of the DRB3*0101 and DRB3*2002 alleles, and also subcloned 5' and 3' flanking regions of the polymorphic DRB3 gene for use in functional studies.     

Pituitary volume in pediatric obsessive-compulsive disorder.

BACKGROUND: Abnormalities in the limbic-hypothalamic-pituitary-adrenal (LHPA) axis have been implicated in the pathogenesis of obsessive-compulsive disorder (OCD). To our knowledge, however, no prior study has measured pituitary gland volume in OCD. METHODS: Volumetric magnetic resonance imaging studies were conducted in 31 psychotropic drug-na?ve children (10 boys, 21 girls) aged 8-17 years and 31 case-matched healthy comparison subjects. RESULTS: Pituitary volume was significantly smaller in patients with OCD as compared with healthy control subjects (11% smaller). Smaller pituitary volume in patients with OCD was associated with increased compulsive but not obsessive symptom severity. Boys with OCD had smaller pituitary gland volumes compared with control boys (20% smaller). No significant differences in pituitary volume were observed between girls with OCD and control girls. Boys with OCD had significantly smaller pituitary volumes than girls with OCD (31% smaller), whereas control boys also had smaller pituitary gland volumes compared with control girls (21% smaller). CONCLUSIONS: These findings provide new evidence of reduced pituitary volume in pediatric OCD that seems to be more prominent in male patients. The observed alterations in pituitary volume are consistent with neuroendocrine studies that have reported abnormalities in the LHPA axis in OCD.