Psychoimmunological effects of dioscorea in ovariectomized rats: role of anxiety level

BACKGROUND

Anxiety levels in rats are correlated with interleukin-2 (IL-2) levels in the brain. The aim of the present study was to investigate the effects of dioscorea (wild yam), a Chinese medicine, on emotional behavior and IL-2 levels in the brain of ovariectomized (OVX) rats.

METHODS

One month after ovariectomy, female Wistar rats were screened in the elevated plus-maze (EPM) test to measure anxiety levels and divided into low anxiety (LA) and high anxiety (HA) groups, which were then given dioscorea (250, 750, or 1500 mg/kg/day) by oral gavage for 27 days and were tested in the EPM on day 23 of administration and in the forced swim test (FST) on days 24 and 25, then 3 days later, the brain was removed and IL-2 levels measured.

RESULTS

Compared to sham-operated rats, anxiety behavior in the EPM was increased in half of the OVX rats. After chronic dioscorea treatment, a decrease in anxiety and IL-2 levels was observed in the HA OVX rats. Despair behavior in the FST was inhibited by the highest dosage of dioscorea.

CONCLUSION

These results show that OVX-induced anxiety and changes in neuroimmunological function in the cortex are reversed by dioscorea treatment. Furthermore, individual differences need to be taken into account when psychoneuroimmunological issues are measured and the EPM is a useful tool for determining anxiety levels when examining anxiety-related issues.

Effects of apomorphine on the expression of learned helplessness behavior

Dopaminergic system and its D1 as well as D2 receptors are involved in the modulation of emotional behavior. This experiment investigated the role of dopaminergic activity in the inescapable stress-induced learned helplessness, a widely used depression animal model, by using the pharmacological manipulation through the apomorphine (APO), an agonist for D1 and D2 receptors, and sulpiride (SUL), a selective D2 antagonist. Male Sprague Dawley rats were used and tested in a shuttle box. In the day-1 session, the rats received a 10-trial (1 min/trial) inescapable stressor: a 3 sec conditioned stimulus (CS; 75 db sound and 250 lux red light) followed by a 10 sec unconditioned stimulus (UCS; electrical foot shock, 0.5 mA). In the day-2 session, a 15-trial active avoidance test, 3 sec CS followed by UCS, was performed 30 min after the administration of APO (0, 0.05, 0.5, 1, and 5 mg/kg, i.p.). The number of failures was counted and the UCS was stopped when the rats did not escape after 15 sec UCS. The results showed that APO at the dosage of 0.5 mg/kg had a tendency to enhance the avoidance behavior. In contrast, the treatment of higher dose of APO, 1 and 5 mg/kg, reduced the number of escape but increased the number of failure. Pretreatment of SUL (5 mg/kg, i.p.), 10 min before 1 mg/kg of APO, significantly enhanced the failure behavior. The present data suggest that the activity of D2 receptor may be associated with the adaptive or protective role in the prevention of escape deficits after exposure to inescapable stress. However, the excessive stimulation of D1 receptor may participate in the failure of coping behavior leading to learned helplessness and therefore in the pathophysiological mechanisms underling the development of depression.

Behavioral effects of d-cycloserine in rats: The role of anxiety level

It has been reported that the glutamatergic N-methyl-D-aspartate (NMDA) receptor is involved in stress responses and that anxiety is the primary response to stress. Although individual differences in anxiety levels of rats have been demonstrated by using the elevated plus-maze (PM) test, the role of NMDA receptor activity in such individuality of anxiety is not clear. Here, we examined whether low (LA) and high (HA) anxiety rats might respond differently to treatment with d-cycloserine (DCS), a partial agonist of the glycine binding site located on NMDA receptors. Male Wistar rats were screened by using the PM and divided into LA and HA subgroups. On the next day, these rats were again tested in the PM, 30 min after the treatment with DCS (5, 10, or 30 mg/kg ip). Five days later, the rats were subjected to a 2-day forced swim (FS) test, receiving the DCS treatment again 30 min before the second day session. The PM data showed that DCS had anxiogenic effects in LA but not HA rats. The immobility of LA or HA rats in the FS test was not affected by DCS. The results indicate that the behavioral effects of DCS depend on the anxiety level of rats and have task-dependent behavioral consequences, suggesting that glycine binding sites on NMDA receptors are involved in individual differences of anxiety level.

Elution, detection, and quantification of polio I, bacteriophages, Salmonella montevideo, and Escherichia coli O157:H7 from seeded strawberries and tomatoes

This study compared the effect of different physical and chemical treatments of strawberries and tomatoes to determine their ability to recover seeded viral and bacterial pathogens from produce surfaces. Solutions of salts, amino acids, complex media, and detergents were compared as eluants. Phosphate-buffered saline (PBS) containing 0.1% Tween 80 eluted the highest number of seeded microorganisms. Elution with this defined solution was then compared under different conditions of physical agitation. Rotary shaking for 20 min at 36 degrees C eluted higher numbers of viruses and bacteria than did low- or high-speed stomaching. Commercially available and laboratory prepared bacteriological differential media were compared for their ability to recover and distinguish eluted Salmonella Montevideo and Escherichia coli O157:H7 strains from seeded produce. The recovery of seeded bacterial pathogens was low when differential media containing selective ingredients were used (MacConkey sorbitol agar, XLD agar, MacConkey agar). Highest recoveries were obtained on a medium consisting of tryptic soy agar supplemented with sodium thiosulfate and ferric ammonium citrate compared with selective media that inhibited up to 50% of the growth of the eluted microorganisms.

Enhanced broth media for selective growth of Vibrio vulnificus

Rapid detection of Vibrio vulnificus can be enhanced by optimizing the components of enrichment broth. PNC (5% peptone, 1% NaCl, and 0.08% cellobiose [pH 8.0]) enhanced the growth of V. vulnificus compared to alkaline peptone broth. PNCC (PNC with 1.0 to 4.1 U of colistin methanesulfonate per ml) increased the growth of low levels of V. vulnificus while suppressing non-target bacteria.

Grating coupler acceptance design utilizing a tapered waveguide structure

A tapered waveguide film was deposited on a substrate with a grating structure resulting in a hybridthin-film waveguide coupler that could be designed for a broader or narrower acceptance for wavelength or incidence angle. The optimized couplers were designed and fabricated. The couplers were found to be as efficient as traditional grating couplers but with much broader acceptance. The maximum broadening was calculated to be a coupling FWHM of 2° (or 12 nm) and was confirmed experimentally. This is 4.3 times the acceptance of an identical untapered structure.

Domain inversion in MgO-diffused LiNbO(3)

We obtain the periodic modulation of domain polarization by patterning MgO on the positive C-face of LiNbO(3), followed by Li outdiffusion to induce domain inversion. We obtain domain inversion lines (1.5 microm) by heat treating LiNbO(3) at 1000 degrees C for 2 h with a 1-microm inversion depth. This process may be suitable for fabrication of first-order gratings that are needed for high second-harmonic conversion efficiency by using a quasi-phase-matched technique.

[Psychogenic dizziness]

Psychogenic dizziness is defined as recurring or persistent symptoms of balance dysfunction, inconsistent with organic vestibular disease as determined by history, clinical examination and pertinent investigations, and consistent with emotional origin. Of 1,335 patients seen in our dizziness clinic between January 1988 and August 1991, psychogenic dizziness was diagnosed in 180 (13.5%) patients. There were 67 men and 113 women aged from 12 to 77 years (mean age 40.2 years). The characteristics of psychogenic dizziness are: (1) continuous dizziness for long periods of time; (2) younger patients; (3) predominant female; (4) associated symptoms of panic attack, such as headache, breathlessness, nausea, sleep disturbance, paresthesias, anxiety and palpitation; (5) symptoms of aggravation due to stressful life events; (6) normal neurotological bedside examination; (7) hyperventilation reproduced accurately. The electronystagmographic results of 74 patients show normal bithermal caloric responses in 47 patients (63.5%), caloric hyperactivity in 21 patients (28.4%), canal paresis in four patients (5.4%), canal paresis with directional preponderance in two patients (2.7%), large random voluntary eye swings or severe blinking in 35 patients (47.3%), and spontaneous nystagmus (slow phase velocity < 6.5 degrees/s) in four patients (5.4%). There were 31 patients who consulted psychiatrists with diagnoses of anxiety (51.6%), depression (16.1%), insomnia (12.9%), psychosomatic disorder and adjustment disorder. Treatment of patients with psychogenic dizziness must be directed at the underlying anxiety. Psychiatric consultation is necessary.

Stress fracture of the diaphysis of the ulna

Stress fracture of the diaphysis of the ulna is rare and only 6 cases were found in a literature review. We present a further case occurring in a weightlifter.

Arnold-Chiari type 1 malformation and syringomyelia

A 12-year-old boy had a long history of headache since the age of 4 years. Numbness and weakness of the upper extremities and chest tightness, especially in the morning, were noted since 2 years ago. The headache became more severe and frequent and attacked even in sleep since one year ago. Arnold-Chiari type 1 malformation, cervical syringomyelia and mild hydrocephalus were demonstrated by MRI scan of the central nervous system. Headache and other symptoms disappeared immediately after surgical intervention. The formation of syringomyelia may be multifactorial, but Arnold-Chiari type 1 malformation and uneventful birth history play an important role in the underlying cause of this case. We presented this youngest case who had Arnold-Chiari type 1 malformation and onset of headache from the age of 4 years, discussed the pathogenesis of syringomyelia and reviewed the literature.

[Harlequin fetus--a case report]

A one-day-old male premature baby was born to a G4P4 mother with the gestation age of 30 weeks. His birth weight was 2000 gm. He was noted to be covered with a thick, armor-like skin which is split by deep fissures and makes the feature of Ectropion and eclabium. His nose was flattened, only the nostrils were visible, and the external ears were underdeveloped. The hands and feet appeared to be swollen and crumpled. The genital organ was covered with thick fissured skin and it was impossible to distinguish sex by external appearance. Three days after delivery, the patient died of respiratory distress. He was found normal through general laboratory and chromosome study. However, dermatohistology showed hyperkeratosis, focal parakeratosis and hypogranulosis. Pathology showed PDA (patent ductus arteriosus), enlarged thymus and congestion of internal organs. Its etiology and pathogenesis somehow remain unknown. We hereby reported this harlequin fetus, the most severe type of lamellar ichthyosis, and discussed its incidence, pathogenesis, pathohistology, prognosis and the recent development in treatment.

[Gilles de la Tourette syndrome associated with epileptiform discharges: report of three cases]

This report presents the clinical observation of 3 cases of Gilles de la Tourette Syndrome (GTS) with epileptiform discharge of electroencephalogram (EEG). During the past 2 years (1986-1987), 8 cases of GTS were diagnosed in the pediatric department of National Taiwan University Hospital. Three of them presented epileptiform discharges. Diffuse bilateral parieto-occipital spikes in waking and light sleep periods were noted in case 1, who was a 10-year-old girl. Case 2 was a 9-year-old boy, his EEG showed sporadic spikes over right fronto-central area during light sleep. In case 3, a 6-year-old boy, frequent sharps and spikes appeared in left centro-temporal area in waking and sleep EEG. Case 3 had received antiepileptic therapy. The EEG recovered to normal, the symptoms of the involuntary movement became more prominent. All of the 3 cases improved significantly after haloperidol monotherapy. Based on the clinical observations and literature review, we noted that the incidence of epileptiform discharge in GTS was higher than that in nonepileptic normal population. Although some authors suggested that a seizure state possibly play a subtle role in the genesis of Tourette's symptoms, this inference was not supported by our experience. We observed that haloperidol was effective to this syndrome with or without epileptiform discharge. Therefore, antiepileptic agents, which might alter the metabolism of dopamine, was not recommended for treating GTS patients.