Chronological changes in astrocytes induced by chronic electrical sensorimotor cortex stimulation in rats

Motor cortex stimulation (MCS) is a treatment option for various disorders such as medically refractory pain, poststroke hemiplegia, and movement disorders. However, the exact mechanisms underlying its effects remain unknown. In this study, the effects of long-term chronic MCS were investigated by observing changes in astrocytes. A quadripolar stimulation electrode was implanted on the dura over the sensorimotor cortex of adult rats, and the cortex was continuously stimulated for 3 hours, 1 week, 4 weeks, and 8 weeks. Immunohistochemical staining of microglia (ionized calcium-binding adaptor molecule 1 [Iba1] staining) and astrocytes (glial fibrillary acidic protein [GFAP] staining), and neuronal degeneration histochemistry (Fluoro-Jade B staining) were carried out to investigate the morphological changes following long-term chronic MCS. Iba1 staining and Fluoro-Jade B staining showed no evidence of Iba1-positive microglial changes or neurodegeneration. Following continuous MCS, GFAP-positive astrocytes were enlarged and their number increased in the cortex and the thalamus of the stimulated hemisphere. These findings indicate that chronic electrical stimulation can continuously activate astrocytes and result in morphological and quantitative changes. These changes may be involved in the mechanisms underlying the neuroplasticity effect induced by MCS.     

Preliminary outcome study on assertive community treatment in Japan

Aims: The beneficial effects of assertive community treatment (ACT), which has been widely acclaimed as being successful in several foreign countries, must also be objectively evaluated with respect to the transition from inpatient to community‐based mental health treatment in Japan. This was the first study that examined effects of the ACT program in Japan using pre/post design data of the pilot trial of the ACT program in Japan project. Methods: The study included 41 subjects hospitalized at Kohnodai Hospital, National Center of Neurology and Psychiatry between May 2003 and April 2004 for severe mental illness and who met inclusion criteria for entry regarding age, diagnosis, residence, utilization of mental health services, social adjustment, and ability to function in daily activities. All subjects provided informed consent for study participation and were followed for 1 year after hospital discharge. Results: Comparison of the number of days and frequency of inpatient psychiatric hospitalization and frequency of emergency psychiatric visits between the 1‐year period before hospitalization and 1‐year period after hospital discharge showed a significant decrease in number of days and frequency of hospitalization. Comparison at 1 year after discharge with baseline showed no change in satisfaction with overall quality of life or Brief Psychiatric Rating Scale scores, but the Global Assessment of Functioning score significantly increased, and the antipsychotic dose (chlorpromazine equivalent) significantly decreased. Conclusion: Despite some limitations in methodology and conclusions, this study suggests that ACT enables persons with severe mental illness to live for longer periods in the community, without worsening of symptoms, decreased social function, or deterioration in quality of life.     

Macrophages in normal cycling human ovaries; immunohistochemical localization and characterization

We evaluated the immunolocalization and characterization of macrophages in 28 normal cycling human ovaries. Two primary antibodies were used to detect the macrophages: PGM1, a general marker for macrophages, and 25F9 which is specific for phagocytosing macrophages. Spindle-shaped cells positive for PGM1 but negative for 25F9 were observed in the stroma (123.6 +/- 1.05 cells/10(-6) m2) and theca layer of the follicle (mean ranged from 22.61 to 53.79) and the number of these cells did not change throughout the cycle. After ovulation, PGM1 positive cells with ballooning bodies began to appear in the early corpus luteum (111.8 +/- 0.83). The number of these macrophages increased in the mid and late corpora lutea, and reached maximum in the early degenerating corpus luteum (1231.0 +/- 3.29). A lower number of PGM1 positive ballooning macrophages were observed in the atretic follicle (177.9 +/- 1.42). 25F9 positive cells were also observed among the PGM1 positive balloon- shaped cells. The number of cells double positive for 25F9 and PGM1 was observed in the mid corpus luteum (44.6 +/- 0.46), increased in the late corpus luteum and early degenerating corpus luteum, and reached plateau in the late degenerating corpus luteum (549.0 +/- 5.82). A lower number of these double positive macrophages were also observed in the atretic follicle (64.8 +/- 0.36). The ratio of 25F9 to PGM1 positive cells increased in parallel with ageing of the corpus luteum (0.19 in the mid corpus luteum, 0.39 in the late corpus luteum, and 0.37 in the early degenerating corpus luteum), and the great majority of PGM1 positive cells were also immunopositive for 25F9 in the late degenerating corpus luteum (0.81). These results suggest that in normal cycling human ovaries, macrophages are mainly involved in luteal regression as scavengers.      

Intraoperative monitoring of the corticospinal motor evoked potential (D-wave): clinical index for postoperative motor function and functional recovery

The corticospinal motor evoked potential was investigated as a monitoring index of motor function to perform maximal resection of brain tumors located around the motor cortex in 37 patients with glioma. Tumor resections were performed under general anesthesia with muscle relaxant and completely controlled ventilation. No special arrangements for anesthesia were required. Direct cortical stimulation revealed that if one electrode was placed on the posterior half of the precentral gyrus, the D-wave could be recorded even when using an electrode separation of 10 mm, and the amplitude was larger with anodic rather than cathodic stimulation. Monitoring of the D-wave enabled the function of the corticospinal tract to be evaluated selectively. Postoperative persistent motor disturbance remained in six patients who had a decrease of over 30% in amplitude of the D-wave during tumor resection. A decrease of less than 30% may indicate postoperative preservation of motor function, including transient motor disturbance with subsequent complete recovery. Intraoperative monitoring of the D-wave is suitable for open cranial surgery with general anesthesia, can detect the primary motor cortex, and allow maximal resection of brain tumors located around the motor cortex.     

Effect of Naloxone on the Bladder Activity of Rabbits with Acute Spinal Injury

Background: Naloxone enhances bladder activity in patients with chronic spinal cord injury. However, there are few reports on naloxone for bladder morbidity in acute spinal cord injury.
Methods: We performed a prospective, controlled study of the effects of naloxone on bladder function in rabbits with and without surgical transection of the spinal cord at the 10th thoracic vertebra. Acute and chronic stages of injury were defined according to bladder function. Naloxone was given intravenously at both stages, and intrathecally at the acute stage. Bladder activity was monitored by cystometry. Blood concentrations of methionine-enkephalin were measured by radioimmunoassay.
Results: Spinal cord injuries were acute 1 or 2 days after surgery, and chronic after 1 or 2 weeks. Bladder capacity significantly decreased after 0.01 mg of intravenous naloxone in uninjured control rabbits, and after 0.03 mg of intravenous naloxone in rabbits with chronic-phase injuries. During the acute-injury phase, 0.3 mg of intravenous naloxone, or 0.02 mg of intrathecal naloxone, was necessary to evoke the micturition reflex. No significant changes in blood enkephalin levels were seen before or after spinal cord injury.
Conclusion: In rabbits with acute spinal cord injury, intrathecal naloxone evoked the micturition reflex at a much lower dose than did intravenous naloxone. Intrathecal naloxone promises to become a new therapy for the acute stage of spinal cord injury for active recovery of bladder function, and could replace current therapy.     

Water hammer and Corrigan's pulses

Corrigan’s pulse is characterized by the abrupt distension and quick collapse of carotid arteries in aortic regurgitation, whereas water hammer pulse is the characteristic pulse observed in peripheral arteries.