Gamma-knife radiosurgery for trigeminal neuralgia

Gamma knife was installed at the PD Hinduja National Hospital and Medical Research Centre, Mumbai, India, in January 1997. In the first year of gamma-knife radiosurgery to January 1998, we treated 110 patients, of whom six had medically refractory trigeminal neuralgia. Seven treatments were administered to this group of six patients (one had bilateral neuralgia). This report evaluates the effectiveness of radiosurgery treatment in these patients. The median age of the patients was 56 years and there were five males and one female. Following Leksell stereotactic frame fixation, a magnetic resonance imaging scan was done in all. The Leksell gamma plan was used for planning. A radiosurgery dose of 70–80 Gy was delivered to the trigeminal root entry zone, 2–4 mm anterior to the junction of the pons and trigeminal nerve with a single 4 mm collimator helmet. Complete pain relief was achieved in four patients. Two had partial relief. No patient developed any radiosurgery related morbidity during the follow-up period of 5–16 months. Radiosurgery seems to be an effective approach for medically or surgically refractory trigeminal neuralgia.     

Effect of methemoglobin formation on the MR appearance of subarachnoid hemorrhage

Subarachnoid hemorrhage has a much higher intensity in magnetic resonance (MR) images with the passage of time. Acute subarachnoid hemorrhage is difficult to see; within 1 week its appearance has become intensified on T1-weighted images. Different concentrations of blood and lysed red blood cells in cerebrospinal fluid (CSF) were examined spectroscopically but did not significantly alter T1 and T2 relaxation of CSF acutely. Ultraviolet visible spectroscopy of bloody CSF stored hypoxically for 3 days showed the presence of methemoglobin. The iron in methemoglobin is paramagnetic; in combination with water this facilitates T1 relaxation. It is concluded that methemoglobin formation with T1 shortening at least partially accounts for the increasing intensity of the MR appearance of subarachnoid hemorrhage over time in the central nervous system and may also explain the intense appearance of subacute hemorrhage in MR images elsewhere in the body.     

In vivo hematopoietic effects of recombinant interleukin-1 alpha in mice: stimulation of granulocytic, monocytic, megakaryocytic, and early erythroid progenitors, suppression of late-stage erythropoiesis, and reversal of erythroid suppression with erythropoietin

Interleukin-1 alpha (IL-1 alpha) is a macrophage-derived, multifunctional cytokine that broadly potentiates myelopoiesis and induces the synthesis of hematopoietic colony-stimulating factors (CSF) in vitro and in vivo. To evaluate the possibility for use of IL-1 alpha in ameliorating in vivo bone marrow suppression induced by drugs or radiation, we examined the in vivo effects of the cytokine on erythropoietic and other hematopoietic progenitor cells. Normal mice were treated with a single intraperitoneal (IP) injection of recombinant human IL-1 alpha at varying doses and were assayed at various times post-treatment. By six hours postinjection, a significant suppression of mature erythroid progenitors (CFU-E) was observed in animals treated with IL-1 alpha (0.5 micrograms/mouse), with maximum suppression of CFU-E and peripheral blood reticulocyte counts occurring at 24 hours. Decreases in peripheral blood hematocrit did not occur after a single IL-1 alpha injection but were observed after multiple injections of the cytokine. The suppressive effects of IL-1 alpha on late-stage erythropoiesis were abrogated by simultaneous administration of erythropoietin (EPO). At 48 hours post-treatment, a marked stimulation was observed in the numbers of spleen and marrow immature erythroid (BFU-E), macrophage (CFU-M), granulocyte (CFU-G), granulocyte- macrophage (CFU-GM), and megakaryocyte (CFU-meg) progenitor cells. These results demonstrate the potential use of IL-1 alpha as a generalized stimulator of hematopoiesis and show that the cytokine- induced suppression of late-stage erythropoiesis can be prevented by EPO.     

The importance of considering biological maturity when assessing physical fitness measures in girls and boys aged 10 to 16 years

It is widely considered that biological maturity influences physical fitness test performance, children can be advantaged/disadvantaged in physical fitness tests by being more or less mature than counterparts of the same chronological age. The current study sought to investigate the effect sexual maturity had upon performance in physical fitness tests. A cross-sectional study involving 161 girls and 152 boys was carried out. Each subject was assessed for stature, mass, self-assessment of sexual maturity, vertical jump, hand grip strength and the 20 m shuttle run test, all procedures were standardized. Spearman's rank correlation coefficients were developed to assess the relationship between maturity and physical fitness measures. ANCOVA inferential statistics were performed to investigate if performance in physical fitness tests differed between children of different sexual maturity stages irrespective of mass and stature. Significance was set at p < 0.05. Stage of sexual maturity was significantly correlated with all physical fitness measures (boys: r=0.56 to 0.73; girls: r=0.24 to 0.46). ANCOVA revealed that when stature and mass were taken into account significant differences were evident between sexual maturity stages in boys but not girls. This suggests that increases in mass and stature are primarily responsible for variation in girls' physical performance throughout maturation, whereas in boys there are some qualitative differences in performance due to other factors. It was concluded that sexual maturity has a large influence on physical fitness measures in boys but less effect in girls. Rating of physical fitness, particularly for boys should take into account biological maturity.     

Prevention and management of food allergy

The phenotypic expression and natural history of food allergy vary widely according to the patient's age, disease presentation and type of offending food. Prevention of food allergy might be achieved by altering the dietary factors responsible for the sensitization and phenotypic expression of the disease. Owing to the peculiarity of the atopic status, a minute amount of allergens can trigger both sensitization and symptoms in atopic individuals. The oral dose of β-lactoglobulin causing sensitization can be estimated to be between 1 ng and several milligrams. In food allergy, sensitization and treatment are allergen specific; therefore, for primary prevention (avoiding sensitization) and secondary prevention of food allergy (avoiding symptoms in an already sensitized subject), a product without immunogenic and allergenic epitopes should be given in each case. Babies of atopic parents are particularly prone to develop food allergy and for this reason they are called high-risk babies. Cow's milk is the most commonly offending food in both gastrointestinal and cutaneous manifestations. Cow's milk proteins are potent allergens and around 2.5% of infants experience cow's milk allergy in the first years of life. The major risk factors for cow's milk allergy are positive family history of atopy and early exposure to cow's milk proteins. Hydrolysate formulae have been developed for the purpose of reducing the allergenicity of cow's milk proteins. More recently, partially and extensively hydrolysed formulae have also been used for feeding babies with a high risk of atopy for the prevention of cow's milk allergy. However, according to the results of a recent randomized controlled study, only an extensively hydrolysated formula, and not a partially hydrolysated formula, significantly decreased the prevalence of cow's milk allergy.     

Successful treatment of severe subcutaneous insulin resistance with inhaled insulin therapy

van Alfen‐van der Velden AAEM, Noordam C, de Galan BE, Hoorweg‐Nijman JJG, Voorhoeve PG, Westerlaken C. Successful treatment of severe subcutaneous insulin resistance with inhaled insulin therapy. The potential of inhaled insulin therapy for severe resistance to subcutaneous insulin was tested in a 7‐yr old boy with type 1 diabetes mellitus. The efficiency of 1 mg inhaled insulin (Exubera^®) was examined by a 4‐h euglycemic clamp study. During the clamp, the glucose infusion rate started to increase 25 min after inhalation and peaked 120 min after inhalation. Subsequently, a trial of inhaled insulin monotherapy was initiated consisting of pre‐meal inhalations and one inhalation during the night. Since glycemic control remained fair (HbA1c ～8.5%), this therapy was continued. Over the ensuing 18 months, mild keto‐acidosis occurred twice during gastro‐enteritis. Inhaled insulin was well tolerated and pulmonary function did not deteriorate. We conclude that severe resistance to subcutaneous insulin does not preclude sufficient absorption of insulin delivered by pulmonary.     

Expert system-controlled image display

Conventional computer-based medical expert systems deliver advice to physicians as written text. While such advice is useful, it has distinct limitations in a visually oriented discipline such as diagnostic radiology, in which decisions often depend on pattern recognition and appreciation of subtle morphologic features. The authors developed a prototype expert computer system, IMAGE/ICON, which displays groups of images sorted into a series of axes based on different ways in which they may be similar. They may share a common feature, group of features, causes, or clinical setting. IMAGE/ICON may display examples of morphologic variations of a dominant finding or a spectrum of abnormalities seen in an specific disease or group of diseases. The system also assembles a written analysis of key features of a case. Such a tool may be useful as a diagnostic aid or for continuing medical education. It is likely to have particular impact in the form of an intelligent radiologic workstation, as picture archiving and communication systems become available.