Dimensional measurement of seasonal variation in mood and behavior.

Recent epidemiologic studies have found that the behaviors that characterize seasonal affective disorder (SAD) show seasonal variation in 92%-95% of the general population, suggesting that seasonal variation in behavior and mood is a continuous, dimensional variable extending throughout the general population, defined at the upper extreme by SAD. Research into population seasonality will require a dimensional measure of seasonal variation in mood and behavior that produces a broad, finely graded distribution of seasonality scores sensitive to individual differences throughout the entire range of scores. Accordingly, the Inventory of Seasonal Variation (ISV) was developed as such a measure. This study demonstrated that the ISV has high internal structural validity and is highly sensitive to individual differences in seasonality across its entire range of scores in the normal population. This latter characteristic is not shared by other existing measures of seasonality. Initial external validity of the ISV was supported in that the mean of ISV scores of a SAD sample was found to lie at the 97th percentile of the normal population of scores. Analysis of ISV scores revealed that a winter pattern of seasonality was reported by over 95% of subjects, a pattern that was more pronounced in women than men, while a summer type of seasonality was reported by only 0.6% of the general population.     

Molecular analysis of neuronal physiology by gene transfer into neurons with herpes simplex virus vectors.

A genetic analysis of mammalian neuronal physiology might now be possible due to the development of defective herpes simplex virus vectors, which allow gene transfer directly into mature neurons, in culture or in the adult brain. Genetically altered proteins that play critical roles in neuronal physiology, including those responsible for the generation of action potentials, synthesis and release of neurotransmitters, and signal transduction enzymes, can now be stably expressed in neurons. The effect of such altered proteins on neuronal physiology can therefore be examined, using the tools of modern neuroscience. Genetic manipulation is biochemically specific and stable, and can be targeted both to a particular cell type and to a particular subregion of the cell to yield insights into the molecular basis for specific brain functions.     

Haemangioma of the maxillary antrum

Haemangioma of the maxillary sinus is rare. Clinical diagnosis is of utmost importance for its operative treatment and prevention of hazards. A case is reported for its rarity and some unusual features.     

Cerebrovascular and metabolic perturbations in delayed heavy charged particle radiation injury

Focal heavy charged particle irradiation of the rabbit brain created defined lesions which were observable by nuclear magnetic resonance (NMR) and positron emission tomography (PET) imaging techniques. The lesions appeared approximately 9-11 months after left partial hemibrain irradiation with 30 Gy (230 MeV/u helium ions), and were restricted to the white matter tracts and deep perithalamic and thalamic regions. 82Rubidium PET and Gadolinium DTPA enhanced NMR imaging were used to detect blood-brain barrier perturbations. 18Fluordeoxyglucose PET studies demonstrated widespread decreases in cerebral glucose uptake in the cortex and thalamus of the irradiated hemisphere. NMR and PET imaging results correlated well with histological findings. Rabbits irradiated with 15 Gy did not demonstrate any abnormalities in the brain with sequential NMR scans through 14 months post-irradiation.     

PADGEM (GMP140) is a component of Weibel-Palade bodies of human endothelial cells

PADGEM protein (PADGEM), also known as GMP140, is a platelet alpha- granule membrane protein that is translocated to the external membrane after platelet activation. Although the biosynthesis of this protein was originally thought to be confined to megakaryocytes, the synthesis of PADGEM in endothelial cells was recently demonstrated (McEver et al: Blood 70:1974a, 1987). We now describe the subcellular localization of this protein in endothelial cells. Immunofluorescence staining of permeabilized human umbilical vein endothelial cells with KC4, a well characterized monoclonal antibody to PADGEM, showed positively stained elongated structures similar in distribution and shape to Weibel-Palade bodies. Their identity as Weibel-Palade bodies was confirmed by double label immunofluorescence using KC4 and a polyclonal antiserum to von Willebrand factor (vWf), a protein known to be specifically stored in these organelles. All Weibel-Palade bodies were found to contain PADGEM. In contrast to strong perinuclear staining produced with anti- vWf antibodies, no significant perinuclear staining was obtained with KC4, indicating that relatively little PADGEM is present in the endoplasmic reticulum and in the Golgi apparatus. In endothelial cells treated with secretagogues that stimulate vWf release the elongated structures positive for PADGEM disappeared, further identifying these structures as Weibel-Palade bodies. This observation extends the parallels between Weibel-Palade bodies and alpha-granules and suggests a possible functional association between vWf and PADGEM.     

COMPUTER SIMULATION OF RESPIRATORY IMPEDANCE AND FLOW TRANSFER FUNCTIONS DURING HIGH FREQUENCY OSCILLATIONS

The usefulness of measuring respiratory flow in the airway andat the chest wall and of measuring respiratory input impedance(Z) to monitor high frequency ventilation was investigated bycomputer simulation using a monoalveolar 10–co-efficientmodel. The latter included a central airway with its resistance(Rw) and inertance (Iw), a resistive peripheral airway (Rp),a lumped bronchial compliance (Cb), alveolar gas compliance(Cgas), lung tissue with its resistance (Rl) and compliance(Cl), and chest wall resistance (Rw), inertance (Iw) and com-pliance(Cw).Gas flow in the peripheral airway (Vp), shunt flow through Cb(Vb), gas compression flow (lgas) and rate of volume changeof the lung (Vl) and of the chest (Vw) were computed and expressedas a function of gas flow in the central airway (Vc). For normalvalues of the coefficients. Vp/Vc was found to decrease moderatelywith increasing frequency and was still 0.75 at 20Hz. Peripheralairway obstruction (Rp x 5) considerably decreased Vp/Vc particularlyat high frequency. It did not change the relationship betweenthe two measurable flows. Vc and Vw, but increased the effectiveresistance at low frequency and shifted the reactance curveto the right. A reduced lung or chest wall compliance producedlittle change in Vp/Vc and Z except at very low frequencies;however, it decreased the phase lag between Viv and Vc. Finally,an increased airway wall compliance decreased Vp/Vc, but hadlittle effect on Z and Vw/Vc. It is concluded that measuringrespiratory impedance may help in detecting some, but not allof the conditions in which peripheral flow convection is decreasedduring high frequency oscillations.