You'll feel better in the morning: slow wave activity and overnight mood regulation in interepisode bipolar disorder

BACKGROUND

Sleep disturbances are prominent correlates of acute mood episodes and inadequate recovery in bipolar disorder (BD), yet the mechanistic relationship between sleep physiology and mood remains poorly understood. Using a series of pre-sleep mood inductions and overnight sleep recording, this study examined the relationship between overnight mood regulation and a marker of sleep intensity (non-rapid eye movement sleep slow wave activity; NREM SWA) during the interepisode phase of BD.

METHODS

Adults with interepisode BD type 1 (BD; n = 20) and healthy adult controls (CTL; n = 23) slept in the laboratory for a screening night, a neutral mood induction night (baseline), a happy mood induction night, and a sad mood induction night. NREM SWA (0.75-4.75 Hz) was derived from overnight sleep EEG recordings. Overnight mood regulation was evaluated using an affect grid pleasantness rating post-mood induction (pre-sleep) and the next morning.

RESULTS

Overnight mood regulation did not differ between groups following the sad or happy inductions. SWA did not significantly change for either group on the sad induction night compared with baseline. In BD only, SWA on the sad night was related to impaired overnight negative mood regulation. On the happy induction night, SWA increased relative to baseline in both groups, though SWA was not related to overnight mood regulation for either group.

CONCLUSIONS

These findings indicate that SWA disruption may play a role in sustaining negative mood state from the previous night in interepisode BD. However, positive mood state could enhance SWA in bipolar patients and healthy adults.

Sex differences in cocaine-stimulated motor behavior: disparate effects of gonadectomy

Sex differences in biological substrates of drug use and addiction are poorly understood. The present study investigated sexual dimorphisms in motor behavior following acute cocaine administration (10, 20, or 40 mg/kg, i.p.). Cocaine increased stereotypy rating, horizontal and vertical activity in both sexes, and effects were always greater in females than males. A population analysis using data from multiple experiments indicated that horizontal activity scores were normally distributed in males but not in females. Gonadectomy induced disparate effects on cocaine-stimulated motor behavior. Population analysis indicated that castrated males exhibited more horizontal activity and stereotypy than shams. Ovariectomy did not affect cocaine-stimulated stereotypy but did attenuate horizontal activity in a subset of rats that had not been vaginally lavaged. In summary, gonadectomy effects were sex and behavioral topography specific and indicate that activational effects of gonadal hormones partially mediate the robust sex differences in cocaine-stimulated open-field behavior.

Sex, steroids, and stimulant sensitivity

The current study investigated ovarian modulation of the locomotor response to cocaine in rats. Ovariectomy in females lowered the response to cocaine (10 mg/kg i.p.), whereas castration did not change that of males. The locomotor responses of prepubertal males and females to cocaine were similar. However, the postpubertal sex difference resulted from a fall in cocaine-stimulated locomotion in males rather than a rise in females. Neonatal testosterone treatment of female rat pups decreased the response to cocaine in adulthood. These findings suggest that both the activational and organizational effects of gonadal steroids contribute to the greater response of females to cocaine.

The role of dual radionuclide scintigraphy in the preoperative localization of abnormal parathyroid glands

Success rates for neck exploration in patients with hyperparathyroidism should exceed 90 per cent in the hands of experienced surgeons. The ability to localize abnormal parathyroid glands preoperatively should maintain or increase the rate of success. Dual isotope subtraction scintigraphy using thallium-201 and technetium-99m pertechnetate offers a noninvasive means of localization. The usefulness of this procedure was studied in thirteen patients with suspected hyperparathyroidism. The scan accurately localized the site of abnormal parathyroid glands (nine adenomas and eight hyperplastic glands) in 91 per cent of the patients. Localization was most successful in adenomas weighing more than 500 mg. We conclude that dual radionuclide scintigraphy is useful in the preoperative location of enlarged parathyroid glands.

Radionuclide evaluation of lung trauma

Nuclear medicine imaging procedures can play a significant role in evaluating the pulmonary complications that are seen in trauma patients. A quantitative method for measuring increased pulmonary capillary permeability that uses Tc-99m HSA allows early diagnosis of acute respiratory distress syndrome (ARDS) and accurately differentiates this condition from pneumonia or cardiogenic pulmonary edema. This technique may be of great value in following the response to therapy. The use of 133Xe to diagnose inhalation injury remains an important diagnostic tool, particularly at hospitals with specialized burn units. Regional decreases in ventilation-perfusion images reliably localize aspirated foreign bodies. Radionuclide techniques that are used to demonstrate gastropulmonary aspiration remain controversial and require further clinical evaluation. Pulmonary perfusion imaging, although nonspecific, may provide the earliest clue for correct diagnosis of fat embolism, air embolism, contusion, or laceration. Furthermore, the possibility of perfusion abnormality due to these uncommon conditions must be remembered whenever trauma patients are evaluated for pulmonary thromboembolism with scintigraphy. Occasionally, liver or spleen scintigraphy may be the most appropriate procedure when penetrating chest trauma also involves these subdiaphragmatic organs.

Scintigraphic detection of occult hemorrhage using RBCs labeled in vitro with technetium Tc 99m sodium pertechnetate

Scintigraphy with RBCs labeled with technetium Tc 99m sodium pertechnetate effectively located the source of hemorrhage in a patient receiving long-term anticoagulant therapy. (The patient was initially seen with a large hematoma on the flank.) More important, the procedure was used to monitor activity in this otherwise-occult bleeding site. Scintigraphic studies may be useful in the management of these difficult clinical problems.

A clinical study of vasectomy failure and recanalization

An analysis was made of the 26 unsuccessful operations from the 2,197 vasectomies performed in a non-profit medical facility. Hhe operations were performed by 6 physicians and significant differences were found in the failure rates. In all instances the tissue removed proved to be vas deferens when examined histologically. Two factors seem to account for the differences of failure rates amoung the physicians; 1) the lenght of vas excised and 2) the character of thechnique. Phsicians with a high rate of success removed a significantly longer section of vas than physicians exhibiting higher failure rates. At least 15 mm. of vas should be excised to maximize the success of the procedure. Excised vas segments less than 15 mm. had up to a 25-fold greater incidence of failure. Although considered of secondary importance, good surgical technique subjectively measured by the minimal amount of accessory tissue attached to the excised vasa was also considered to aid in reducing the number of vasectomy failures.