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All known brachyceran flies have inherited the same trapezoidal pattern of rhabdomeres in the ommatidia of the compound eye, different from that of their presumed nematoceran ancestors. The projection pattern of axons to lamina cartridges needs to match this in order to generate efficient neural superposition vision. This pattern has been traced in serial sections or via stimulated dye uptake in two families that diverged from the dipteran stem line more than 200 million years ago (Rhagionidae, Stratiomyidae) and in one family of intermediate age (Dolichopodidae). All show the same asymmetric projection as modern muscoid families and a concordantly 180 degrees-twisted axon bundle, suggesting that evolution to the 'modern' versions of both optics and projection coincided closely in evolutionary time. The basic developmental plan of the cartridge has also been retained since the origin of the Brachycera, but the synaptic participation of at least one axon (that of photoreceptor R7) varies markedly between species.

We have recently collected clinical information on 37 individuals with deletion of 22q13 and compared the features of these individuals with 24 previously reported cases. The features most frequently associated with this deletion are global developmental delay, generalized hypotonia, absent or severely delayed speech, and normal to advanced growth. Minor anomalies include dolicocephaly, abnormal ears, ptosis, dysplastic toenails, and relatively large hands. As with many terminal deletions involving pale G-band regions, the deletion can be extremely subtle and can go undetected on routine cytogenetic analysis. In fact, 32% of the individuals in our study had previous chromosome analyses that failed to detect the deletion. Eight of 37 individuals had deletion of 22q13 secondary to an unbalanced chromosome translocation. In the newborn, this deletion should be considered in cases of hypotonia for which other common causes have been excluded. In the older child, this syndrome should be suspected in individuals with normal growth, profound developmental delay, absent or delayed speech, and minor dysmorphic features. We recommend high-resolution chromosome analysis and fluorescence in situ hybridization studies, or molecular analysis to exclude this diagnosis.

Research has documented a high incidence of comorbid post-traumatic stress disorder (PTSD) and substance abuse. Women substance abusers, in particular, show high rates of this dual diagnosis (30% to 59%), most commonly deriving from a history of repetitive childhood physical and/or sexual assault. Rates for men are two to three times lower and typically stem from combat or crime trauma. Patients with both disorders are characterized by high severity on a multitude of psychological and treatment variables and use of the most severe drugs (cocaine and opioids). Treatment research on women is limited but suggests the possibility of retaining patients and achieving positive outcomes.

Tibial geometry and mechanical properties in male and female rapidly growing rats were measured to provide comparative data for spaceflight, exercise, or disease experiments that use immature rats as an animal model. A total of 68 immature Sprague-Dawley rats (43-58 d of age) were divided into 8 groups according to age and sex. Tibial length and middiaphysial cross-sectional data were analyzed, and tibial mechanical properties were obtained via three-point bending tests to failure. Results indicated that tibial geometry and mechanical properties were changed significantly during this 15-d period of rapid growth, with male rats having greater increases than female rats. Both male and female tibial lengths nevertheless increased significantly during this growth period, as did middiaphysical cross-sectional area. Tibial flexural rigidity increased significantly for both sexes during this growth period. The male tibiae changed primarily in structural characteristics, but some material properties also changed with age. In the female rats, however, the major changes in mechanical properties of the tibia were attributable only to structural changes in the bone.

The plasma concentrations, tissue distribution and excretion of prostaglandin A1 (PGA1) and related metabolites have been determined in rats, following the intravenous injection of a single dose of PGA1-5,6-3H. Urinary and faecal excretion accounted for averages of 25 and 43%, of the administered dose of PGA1, respectively. Oxidative cleavage of the carboxyl side chain of PGA1 appeared to be a major metabolic pathway in the rat. PGA1-5,6-3H was deemed unsuitable for metabolism studies in man, in view of the significant loss of tritium label from the prostaglandin.

The urinary metabolites of arbaprostil-3H in the male rat were profiled, isolated, and purified. Their structures were deduced by gas chromatography/mass spectrometry (GC/MS) studies after conversion to the methyl ester-methoxime-trimethylsilyl ether derivatives, aided by GC with simultaneous radioactivity monitoring. The identified metabolites accounted for over 91% of the urinary excretion products. beta-oxidation of the carboxy side-chain of arbaprostil to 15-methyl-tetranor PGE1 appeared to be the most significant metabolic pathway. Conversion to the dinor A and B derivatives and further beta-oxidation of these to the 15-methyl-tetranor A and B metabolites also appeared to occur. C-19-hydroxylated tetranor A and B derivatives of arbaprostil-3H were excreted in the urine. No conjugated urinary metabolites were evident.

The morphological and mechanical responses of tibia and humerus were assessed in growing male rats after a 1-wk spaceflight aboard NASA Spacelab 3. In contrast to flights of longer duration, changes in middiaphysial cross-sectional morphology were minimal. Inhibition of longitudinal growth was not found in the tibia but was apparent in the humerus. The normal age-related increase in tibial middiaphysial density was not observed in the flight animals. Three-point bending tests indicated that a 1-wk spaceflight impeded the maturation of bone strength and stiffness, with the effects more pronounced in the tibia than in the humerus. Material property alterations in bone thus overshadowed morphological factors in determining the bone's mechanical response. It is likely that deprivation of normal weight-bearing loads was a major factor contributing to the observed changes, but endocrine and other local factors must also be considered.

A single dose of arbaprostil-11 beta-3H (4 micrograms/kg) was administered orally to male rats. A maximum plasma radioactivity concentration equivalent to 2.5 to 2.8 nanograms of the prostaglandin per ml was reached at 30 minutes and was maintained until 120 minutes after drug administration. The plasma drug disappearance half-life was 2.6 hours. These results along with data from tissue distribution studies suggested a rapid uptake of radiolabeled arbaprostil by the glandular stomach tissue followed by an apparent zero-order release of drug-related radioactivity from this tissue "reservoir" into the plasma. Drug-related radioactivity was excreted rapidly, with 96 to 99% of the urinary excretion and 82 to 97% of the fecal excretion being completed within 24 hours. A total of 49.6 +/- 3.5% of the orally administered dose was excreted in the urine and 46.7 +/- 3.9% in the feces. No radioactive residues were detected in the animals at the end of the 120 hour specimen collection period. The metabolic stability of the 11 beta-tritium label and the suitability of arbaprostil-3H for use in human studies was demonstrated.

Musca and related flies have three main photoreceptor subsystems. The R1-6 group has short axons that terminate in the cartridges of the first optic neuropile, the lamina. The cartridges are bypassed by the longer axons of R7 and R8, which run together to terminate at different levels in the underlying medulla neuropile. The present account describes a shallow, previously unidentified zone in the lamina within which R7/8 make glancing contact with R1-6. At the distal border of the cartridge over no more than 3-4 microns depth, the tangentially directed short axon of R6 squeezes between the pair from R7 and R8, forming quite large areas of mutual contact (approximately 7 microns2). Less frequently, R1 is contacted. At least some of these sites contain smaller membrane specialisations indistinguishable from the more numerous gap junctions found more proximally that interconnect the terminals of R1-6. The R7/8 junctions with R6 are of comparable size (0.15 micron 2) and likewise possess symmetrical membrane densities. They provide proposed pathways for direct electrical interaction to account for observed electrical input from R7/8 to the R1-6 subsystem. In two cases R7/8 was possibly postsynaptic to R1-6 at a multiple-contact synapse, but even if functional, these sites were so rare that they are unlikely to have much operational significance.