Axial rotation in the lumbar spine and gaping of the zygapophyseal joints

Axial rotation and zygapophyseal joint gaping was studied using 12 human lumbar spines from individuals ranging in age from 14 to 75 years. Using weight and pulley tests and manipulative testing in a torque apparatus, the movement produced by twisting the spine was found not to be pure axial rotation, but rather movement coupled with various combinations of lateral bending and flexion or extension. This motion may not be possible in testing an individual mobile segment. The twisting movements of the spine do not normally produce gaping of the zygapophyseal joints. These joints adapt to the axial rotation by the compliance of their articular cartilages and the movement of fat pads in and out of the joint capsule. Hypermobility appears to be associated with evidence of damage to part of the mobile segment, suggesting that the hypermobility (gaping) at a joint could be due to instability caused by injury.     

Adrenarche and the evolution of human life history.

Adrenarche, the prepubertal onset of adrenal production of dehydroepiandrosterone sulfate (DHEAS), is a distinctive aspect of the human life course. Yet its evolutionary origins remain unexplained. Production of DHEAS is associated with the development of the zona reticularis, a novel histological layer within the adrenal gland, derived from the fetal adrenal gland, and associated with primates more generally. Evidence that DHEAS is a neurosteroid, together with the fact that increases in DHEAS parallel patterns of cortical maturation from approximately age 6 years to the mid-20s, suggests that DHEAS may play an important role in extended brain maturation among humans. DHEAS has demonstrated effects on mood in humans, and acts at neuron receptor sites. I suggest three ways in which DHEAS may play a role in human brain maturation: 1) increasing activity of the amgydala; 2) increasing activity of the hippocampus; and 3) promoting synaptogenesis within the cortex. I propose that associated changes in fearfulness and anxiety, and memory, could act to increase social interaction with nonfamiliar individuals and shape cognitive development. Comparison with the African apes suggests that the timing of adrenarche in chimpanzees may be similar to that in humans, though the full course of age-related changes in DHEAS and their relationship to reproductive and brain maturation are not clear. The role of DHEAS as a physiological mechanism supporting increased brain development, extended life span, and decreased sexual dimorphism is most compatible with Kaplan et al.'s (2000) theory of the evolution of human life history and intergenerational transfers.     

Pycnogenol® as an Adjunct in the Management of Childhood Asthma

A randomized, placebo-controlled, double-blind study involving 60 subjects, aged 6-18 years old, was conducted over a period of 3 months to determine the effect of Pycnogenol® (a proprietary mixture of water-soluble bioflavonoids extracted from French maritime pine) on mild-to-moderate asthma. After baseline evaluation, subjects were randomized into two groups to receive either Pycnogenol® or placebo. Subjects were instructed to record their peak expiratory flow with an Assess® Peak Flow Meter each evening. At the same time, symptoms, daily use of rescue inhalers (albuterol), and any changes in oral medications were also recorded. Urine samples were obtained from the subjects at the end of the run-in period, and at 1-, 2-, and 3-month visits. Urinary leukotriene C₄/D₄/E₄ was measured by an enzyme immunoassay. Compared with subjects taking placebo, the group who took Pycnogenol® had significantly more improvement in pulmonary functions and asthma symptoms. The Pycnogenol® group was able to reduce or discontinue their use of rescue inhalers more often than the placebo group. There was also a significant reduction of urinary leukotrienes in the Pycnogenol® group. The results of this study demonstrate the efficacy of Pycnogenol® as an adjunct in the management of mild-to-moderate childhood asthma.     

Bile acid receptors in colorectal cancer

Bile acids are thought to be involved in both the aetiology and development of colorectal cancer. In this study the existence of specific bile acid receptor proteins has been postulated. A receptor assay which involved labelling with 14C-deoxycholic acid was performed as well as autoradiography using 3H-deoxycholic acid. In an initial study resected colorectal cancer and adjacent histologically normal colorectal mucosa from 39 patients were studied, as were samples of normal gastric mucosa, cancers and benign colorectal tumours. Specific receptors to deoxycholic acid were detected in 12 (30.8 per cent) of the colorectal cancers, but in only 1 (2.6 per cent) of the samples from normal colorectal mucosa (X2 = 11.16, P less than 0.005). No deoxycholic acid receptors were detected in any other tissue studied. Autoradiographs of colorectal cancers showed binding of 3H-deoxycholic acid in receptor-positive tumour tissue. These findings might provide some explanation for the evidence linking bile acids with the disease.     

Compulsive respiratory stereotypies in children with autistic features: Polygraphic recording and treatment with fenfluramine

Syncopes due to compulsive respiratory stereotypies were studied in eight patients with autistic features. Most had been referred for episodes thought to be intractable epileptic seizures. Polygraphic recording showed two types of syncope, one induced by prolonged apnea and the other by a prolonged Valsalva maneuver. Fenfluramine, 1.5–3 mg/kg per day, was given in an open trial. In four of five cases with frequent Valsalva maneuvers, respiratory stereotypies and syncopes were suppressed for 2–18 months. Patients with periodic apneas were more severely retarded and had less clear benefit. Side effects consisted of dose-dependent sedation and mild weight loss which stabilized without interrupting treatment. We suggest that these syncopes are volitional and may be associated with pleasant sensations. A double-blind placebo-controlled trial of fenfluramine seems warranted in such patients.     

Ivermectin treatment of onchocerciasis

Ivermectin is a recently developed macrocyclic lactone that has widespread antiparasitic activity. A series of clinical trials has shown that ivermectin is safe and effective in the treatment of human infection with Onchocerca volvulus. Although it is rapidly microfilaricidal, it does not cause a severe reaction as is seen with diethylcarbamazine treatment. The drug also temporarily interrupts production of microfilaria but has no known long-lasting effects on the adult worms. In patients with onchocerciasis, a single oral dose of ivermectin (150 micrograms/kg) repeated once a year leads to a marked reduction in skin microfilaria counts and ocular involvement. At this dose, ivermectin causes minimal side effects and appears to be sufficiently free of severe adverse reactions to be used on a mass scale. Its use promises to revolutionise the treatment of onchocerciasis.