Effects of high-peak pulsed electromagnetic field on the degeneration and regeneration of the common peroneal nerve in rats

Apart from preliminary notices of present work, previous reports of experimental and clinical trials of the effects of a high-peak pulsed electromagnetic field (PEMF) on degeneration and regeneration of peripheral nerves lacked statistical analysis. Therefore, we designed experiments with standardised operative, histological, cytological and morphometric techniques to assess the effect of PEMF on lesions of the common peroneal nerves in paired male rats matched for age, environmental conditions and level and type of lesion. One of two types of lesion was induced in the left common peroneal nerve: in 12 pairs of rats the nerve was crushed just above the knee and in the remaining 12 pairs the nerve was cut and immediately sutured at the same level. The right common peroneal nerve of each rat served as a control. Animals received 15 minutes of PEMF produced by a Diapulse machine or sham treatment daily for periods ranging from three and a half days to eight weeks after injury. Healthy nerves were unaffected, but after damage there were statistically significant differences between PEMF treated and sham treated rats. PEMF accelerated the recovery of injured limbs and the degeneration, regeneration and maturation of myelinated axons; epineural, perineural and intraneural fibrosis was reduced; and the luminal cross-sectional area of intraneural vessels increased after both types of lesion. Findings are discussed and the need for clinical trials is stressed.     

Effects of carbamazepine on plasma haloperidol levels

Plasma haloperidol levels were monitored in three schizophrenic patients when carbamazepine was either added or discontinued. The percent decrease in plasma haloperidol levels due to concomitant carbamazepine therapy was between 59% and 61%. The effects of carbamazepine on plasma haloperidol levels were noted to occur in 2 to 3 weeks. Although no adverse effects occurred in the patients during therapy, careful monitoring of clinical symptoms and plasma haloperidol levels is recommended.     

Clonal diversity and turnover of Streptococcus mitis bv. 1 on shedding and nonshedding oral surfaces of human infants during the first year of life

Streptococcus mitis bv. 1 is a pioneer colonizer of the human oral cavity. Studies of its population dynamics within parents and their infants and within neonates have shown extensive diversity within and between subjects. We examined the genetic diversity and clonal turnover of S. mitis bv. 1 isolated from the cheeks, tongue, and primary incisors of four infants from birth to 1 year of age. In addition, we compared the clonotypes of S. mitis bv. 1 isolated from their mothers' saliva collected in parallel to determine whether the mother was the origin of the clones colonizing her infant. Of 859 isolates obtained from the infants, 568 were unique clones. Each of the surfaces examined, whether shedding or nonshedding, displayed the same degree of diversity. Among the four infants it was rare to detect the same clone colonizing more than one surface at a given visit. There was little evidence for persistence of clones, but when clones were isolated on multiple visits they were not always found on the same surface. A similar degree of clonal diversity of S. mitis bv. 1 was observed in the mothers' saliva as in their infants' mouths. Clones common to both infant and mothers' saliva were found infrequently suggesting that this is not the origin of the infants' clones. It is unclear whether mucosal immunity exerts the environmental pressure driving the genetic diversity and clonal turnover of S. mitis bv. 1, which may be mechanisms employed by this bacterium to evade immune elimination.     

Treatment options for bipolar depression

Bipolar disorder is often misdiagnosed as major depressive disorder because of the high frequency of depressive symptomatology in many patients with bipolar disorder. Depressive episodes that are resistant to treatment may also be associated with a worse course of illness in bipolar disorder, but we do not yet understand all the factors in the connection between bipolar disorder and depression. The data on the effectiveness of antidepressants in the treatment of depression in bipolar disorder vary greatly, and there have been few prospective, randomized studies on the subject. From the data so far, the rates of induction of mania for selective serotonin reuptake inhibitors and lamotrigine seem similar to those seen with placebo. The optimal length of time to continue antidepressant treatment in patients with bipolar disorder has not yet been determined; however, research tends to indicate that a longer term of treatment (6 months or more) may aid in the prevention of relapse. Newer U.S. Food and Drug Administration-approved treatments for depression in bipolar disorder include a combination of olanzapine and fluoxetine, which is used for depressive episodes in bipolar disorder, and lamotrigine, which is used for maintenance treatment of bipolar I disorder. Psychoeducation has also been examined as a possible treatment for depression in bipolar disorder, and a study has shown that patients receiving psychoeducation plus medication may have a lower rate of relapse than patients who receive medication alone.     

Study of humoral immunity to commensal oral bacteria in human infants demonstrates the presence of secretory immunoglobulin A antibodies reactive with Actinomyces naeslundii genospecies 1 and 2 ribotypes

The mouths of three human infants were examined from birth to age 2 years to detect colonization of Actinomyces naeslundii genospecies 1 and 2. These bacteria did not colonize until after tooth eruption. The diversity of posteruption isolates was determined by ribotyping. Using immunoblotting and enzyme-linked immunosorbent assay, we determined the reactivity of secretory immunoglobulin A (SIgA) antibodies in saliva samples collected from each infant before and after colonization against cell wall proteins from their own A. naeslundii strains and carbohydrates from standard A. naeslundii genospecies 1 and 2 strains. A. naeslundii genospecies 1 and 2 carbohydrate-reactive SIgA antibodies were not detected in any saliva sample. However, SIgA antibodies reactive with cell wall proteins were present in saliva before these bacteria colonized the mouth. These antibodies could be almost completely removed by absorption with A. odontolyticus, a species known to colonize the human mouth shortly after birth. However, after colonization by A. naeslundii genospecies 1 and 2, specific antibodies were induced that could not be removed by absorption with A. odontolyticus. Cluster analysis of the patterns of reactivity of postcolonization salivary antibodies from each infant with antigens from their own strains showed that not only could these antibodies discriminate among strains but antibodies in saliva samples collected at different times showed different reactivity patterns. Overall, these data suggest that, although much of the salivary SIgA antibodies reactive with A. naeslundii genospecies 1 and 2 are directed against genus-specific or more broadly cross-reactive antigens, species, genospecies, and possibly strain-specific antibodies are induced in response to colonization.     

Lamotrigine treatment of bipolar disorder: data from the first 500 patients in STEP-BD

Objective:  To describe the frequency and correlates of lamotrigine therapy among the first 500 patients enrolled into the Systematic Treatment Enhancement Program for Bipolar Disorder (STEP-BD) study.
Method:  Systematic recording of psychiatric history and medication data at intake into the STEP-BD project.
Results:  Of the participants with bipolar disorder type I or II (n = 483), 77 (15.4%) were currently taking lamotrigine (mean dose: 258.12 mg/day) and 52 (10.4%) reported prior lamotrigine use. The groups were comparable with regard to duration of illness and mood state at study entry. Compared with participants who had never taken lamotrigine, those currently treated with lamotrigine were significantly more likely to have a prior history of rapid cycling (62.5% vs. 43.1%; p < 0.01) and an antidepressant-induced switch to (hypo)mania (49.3% vs. 33.3%; p < 0.01). In contrast, only 16.9% of lamotrigine-treated participants were taking an antidepressant at study intake, as compared with 29.1% of participants with no history of lamotrigine therapy (p < 0.03).
Conclusions:  While noting the limitations of a cross-sectional assessment, these data suggest that lamotrigine therapy was commonly used in these academic centers for patients with bipolar disorder several years before it was recommended in the American Psychiatric Association practice guidelines, particularly in patients with a history of rapid cycling or antidepressant-induced mania.