Spaceflight-Relevant Challenges of Radiation and/or Reduced Weight Bearing Cause Arthritic Responses in Knee Articular Cartilage.

There is little known about the effect of both reduced weight bearing and exposure to radiation during spaceflight on the mechanically-sensitive cartilage lining the knee joint. In this study, we characterized cartilage damage in rat knees after periods of reduced weight bearing with/without exposure to solar-flare-relevant radiation, then cartilage recovery after return to weight bearing. Male Sprague Dawley rats (n = 120) were either hindlimb unloaded (HLU) via tail suspension or remained weight bearing in cages (GROUND). On day 5, half of the HLU and GROUND rats were 1 Gy total-body X-ray irradiated during HLU, and half were sham irradiated (SHAM), yielding 4 groups: GROUND-SHAM; GROUND-IR; HLU-SHAM; and HLU-IR. Hindlimbs were collected from half of each group of rats on day 13. The remaining rats were then removed from HLU or remained weight bearing, and hindlimbs from these rats were collected on day 62. On day 13, glycosaminoglycan (GAG) content in cartilage lining the tibial plateau and femoral condyles of HLU rats was lower than that of the GROUND animals. Likewise, on day 13, immunoreactivity of the collagen type II-degrading matrix metalloproteinase-13 (MMP-13) and of a resultant metalloproteinase-generated neoepitope VDIPEN was increased in all groups versus GROUND-SHAM. Clustering of chondrocytes indicating cartilage damage was present in all HLU and IR groups versus GROUND-SHAM on day 13. On day 62, after 49 days of reloading, the loss of GAG content was attenuated in the HLU-SHAM and HLU-IR groups, and the increased VDIPEN staining in all treatment groups was attenuated. However, the increased chondrocyte clustering remained in all treatment groups on day 62. MMP-13 activity also remained elevated in the GROUND-IR and HLU-IR groups. Increased T2 relaxation times, measured on day 62 using 7T MRI, were greater in GROUND-IR and HLU-IR knees, indicating persistent cartilage damage in the irradiated groups. Both HLU and total-body irradiation resulted in acute degenerative and pre-arthritic changes in the knee articular cartilage of rats. A return to normal weight bearing resulted in some recovery from cartilage degradation. However, radiation delivered as both a single challenge and when combined with HLU resulted in chronic cartilage damage. These findings suggest that radiation exposure during spaceflight leads to and/or impairs recovery of cartilage upon return to reloading, generating long-term joint problems for astronauts.

Early supplementation with Lactobacillus rhamnosus HN001 reduces eczema prevalence to 6 years: does it also reduce atopic sensitization?

BACKGROUND: The role of probiotics in prevention of allergic disease is still not clear; efficacy may depend on the timing, dose, duration, and specific probiotic used. Using a double-blind randomized placebo-controlled trial (Australian New Zealand Clinical Trials Registry: ACTRN12607000518460), we have shown that in a high-risk birth cohort, maternal supplementation from 35 weeks gestation until 6 months if breastfeeding and infant supplementation from birth until 2 years with Lactobacillus rhamnosus HN001 (HN001) (6 × 10(9) cfu/day) halved the cumulative prevalence of eczema at 2 and 4 years. Bifidobacterium animalis subsp lactis HN019 (HN019) (9 × 10(9) cfu/day) had no significant effect. OBJECTIVE: To determine whether differences in effects of HN001 and HN019 on eczema persist to age 6 years, and to investigate effects on sensitization. METHODS: Standard procedures were used to assess eczema (The UK Working Party's Criteria), eczema severity (SCORAD), atopic sensitization [skin prick tests (SPT), total and specific IgE] and standard questions used for asthma, wheeze, and rhinoconjunctivitis. RESULTS: HN001 was associated with significantly lower cumulative prevalence of eczema (HR = 0.56, 95% CI 0.39-0.80), SCORAD ≥ 10 (HR = 0.69, 0.49-0.98) and SPT sensitization (HR = 0.69, 95% CI 0.48-0.99). The point prevalence of eczema (RR = 0.66, 95% CI 0.44-1.00), SCORAD ≥ 10 (RR = 0.62, 95% CI 0.38-1.01) and SPT sensitization (RR = 0.72, 95% CI 0.53-1.00) were also reduced among children taking HN001. HN019 had no significant effect on any outcome. CONCLUSION AND CLINICAL RELEVANCE: This study provides evidence for the efficacy of the probiotic L. rhamnosus HN001 in preventing the development of eczema and possibly also atopic sensitization in high risk infants to age 6 years. The absence of a similar effect for HN019 indicates that benefits may be species specific.

A protective effect of Lactobacillus rhamnosus HN001 against eczema in the first 2 years of life persists to age 4 years.

BACKGROUND: Using a double blind randomized placebo-controlled trial (Australian New Zealand Clinical Trials Registry: ACTRN12607000518460), we have shown that in a high risk birth cohort, maternal supplementation from 35 weeks gestation until 6 months if breastfeeding and infant supplementation until 2 years with Lactobacillus rhamnosus HN001 (HN001) (6 × 10(9) cfu/day) halved the cumulative prevalence of eczema by age 2 years. Bifidobacterium animalis subsp lactis HN019 (HN019) (9 × 10(9) cfu/day) had no effect. OBJECTIVE: The aim of this study was to investigate the associations of HN001 and HN019 with allergic disease and atopic sensitization among these children at age 4 years, 2 years after stopping probiotic supplementation. METHODS: The presence (UK Working Party's Diagnostic Criteria) and severity SCORing Atopic Dermatitis (SCORAD) of eczema and atopy (skin prick tests) and parent-reported symptoms of asthma and rhinoconjunctivitis were assessed using standard protocols and questions. RESULTS: Four-hundred and seventy-four infants were eligible at birth of whom 425 (90%) participated in this follow-up. The cumulative prevalence of eczema by 4 years (Hazard ratio (HR) 0.57 (95% CI 0.39-0.83)) and prevalence of rhinoconjunctivitis at 4 years (Relative risk 0.38 (95% CI 0.18-0.83)) were significantly reduced in the children taking HN001; there were also nonsignificant reductions in the cumulative prevalence of SCORAD ≥ 10 (HR 0.74 (95% CI 0.52-1.05), wheeze (HR 0.79 (95% CI 0.59-1.07)) and atopic sensitization (HR = 0.72 (95% CI 0.48-1.06)). HN019 did not affect the prevalence of any outcome. CONCLUSIONS AND CLINICAL RELEVANCE: This study showed that the protective effect of HN001 against eczema, when given for the first 2 years of life only, extended to at least 4 years of age. This, together with our findings for a protective effect against rhinoconjunctivitis, suggests that this probiotic might be an appropriate preventative intervention for high risk infants.

Bovine milk fat enriched in conjugated linoleic and vaccenic acids attenuates allergic dermatitis in mice.

BACKGROUND: Orally administered milk fat enriched in conjugated linoleic acid (CLA) and trans-vaccenic acid (VA) ('enriched milk fat'), produced by supplementing the diet of pasture-fed cows with fish and sunflower oil, has been shown previously to suppress the development of allergic airway disease in mice. OBJECTIVE: To investigate whether topical or oral application of enriched milk fat and its two major fatty acids cis-9, trans-11 CLA (c9,t11-CLA) and VA inhibit allergic dermatitis in mice. METHODS: Allergic dermatitis was induced in C57BL/6 mice by epicutaneous sensitization of tape-stripped skin with ovalbumin (OVA). Enriched milk fat and its two major fatty acids were either topically applied to the OVA-sensitized skin, or orally fed to mice by supplementation of the diet. Blood and skin tissues were collected for analysis after the third skin sensitization. RESULTS: Both topical and oral administration of enriched milk fat and its two major fatty acids led to significant suppression of allergic dermatitis as evidenced by reduced clinical and histological scores of affected skins, infiltration of inflammatory cells, and circulating allergen-specific IgE levels, compared with treatment with normal milk fat or the base control diet. C9,t11-CLA and VA individually inhibited multiple facets of allergic dermatitis when topically applied, and their combination produced a strong additive effect. CONCLUSION AND CLINICAL RELEVANCE: Enriched milk fat, and its two major fatty acids c9,t11-CLA and vaccenic acid attenuate allergic dermatitis in mice.

Bovine milk fat enriched in conjugated linoleic and vaccenic acids attenuates allergic airway disease in mice.

BACKGROUND: It has been argued that a reduction in the Western diet of anti-inflammatory unsaturated lipids, such as n-3 polyunsaturated fatty acids, has contributed to the increase in the frequency and severity of allergic diseases. OBJECTIVE: We investigated whether feeding milk fat enriched in conjugated linoleic acid and vaccenic acids (VAs) ('enriched' milk fat), produced by supplementing the diet of pasture-fed cows with fish and sunflower oil, will prevent development of allergic airway responses. METHODS: C57BL/6 mice were fed a control diet containing soybean oil and diets supplemented with milk lipids. They were sensitized by intraperitoneal injection of ovalbumin (OVA) on days 14 and 28, and challenged intranasally with OVA on day 42. Bronchoalveolar lavage fluid, lung tissues and serum samples were collected 6 days after the intranasal challenge. RESULTS: Feeding of enriched milk fat led to marked suppression of airway inflammation as evidenced by reductions in eosinophilia and lymphocytosis in the airways, compared with feeding of normal milk fat and control diet. Enriched milk fat significantly reduced circulating allergen-specific IgE and IgG1 levels, together with reductions in bronchoalveolar lavage fluid of IL-5 and CCL11. Treatment significantly inhibited changes in the airway including airway epithelial cell hypertrophy, goblet cell metaplasia and mucus hypersecretion. The two major components of enriched milk fat, cis-9, trans-11 conjugated linoleic acid and VA, inhibited airway inflammation when fed together to mice, whereas alone they were not effective. CONCLUSION: Milk fat enriched in conjugated linoleic and VAs suppresses inflammation and changes to the airways in an animal model of allergic airway disease.

Treatment of malignant astrocytomas with repetitive resections: a longitudinal study.

BACKGROUND: The impact of repeated surgical resection on the survivorship of patients with malignant astrocytomas is an issue of some controversy in the medical literature. OBJECTIVES: To clarify this issue through a retrospective analysis of treatment outcomes in a brain tumor clinic. METHODS: The patient records from the Brain Tumor Clinic at Hahnemann University Hospital for the period 1988 to 2000 were reviewed. From these, 112 cases of glioblastoma multiforme and 50 cases of anaplastic astrocytoma were chosen for analysis. RESULTS: The group of patients with glioblastomas showed a median survival of 415 days. When analyzed as subgroups based on the number of surgical resections, the median survival was 393 days in the group with biopsy only, 380 days in the group with one surgical resection, and 548 days in the group with two or three resections. Using the Kaplan-Meier method to generate survival plots and the log rank test to compare groups, repeat debulking was found to be a significant predictor of survival (P = 0.173). The group of patients with anaplastic astrocytomas showed a median survival of 1,311 days. When analyzed by subgroups, the patients with biopsy only had a median survival of 544 days, those with one debulking 1,589 days and those with two or three debulkings 1,421 days. There was a trend toward increased survival with debulking and the log rank test again showed statistical significance (P = 0.1998). CONCLUSIONS: This study indicates that repeated surgical resections offer increased survival for both glioblastomas and anaplastic astrocytomas.

Providing information on complementary and alternative therapies and practitioners by producing a directory of practitioners.

This article describes the experience of the authors in producing a booklet to provide information on complementary and alternative therapies (CAM) in their local area. The practical steps needed to produce a booklet are described, including ways of involving local general practitioners, meeting with local therapists, recruiting contact persons for each therapy, designing and producing a booklet and launching the final version. The feedback from general practitioners and CAM practitioners is reported.

Expression of cyclooxygenase 2 (COX-2) in human glioma and in vitro inhibition by a specific COX-2 inhibitor, NS-398.

The up-regulation of cyclooxygenase 2 (COX-2) expression is a frequent occurrence in a variety of different tumors. In this study, COX-2 protein expression was investigated in 50 glioma and 3 normal brain specimens by immunohistochemistry. Expression of COX-2 protein was observed in all normal brain and glioma specimens by immunohistochemistry, regardless of histological grade. The immunoreactive score was significantly higher in high-grade glioma than low-grade glioma and normal brain specimens. For a subset of these tumors (nine gliomas and three normal brain), Western blot analysis was also performed. COX-2 protein was detected in all specimens by Western blot analysis. The effect of the specific COX-2 inhibitor NS-398 on monolayer cell cultures and three-dimensional glioma spheroids was investigated using U-87MG and U-251MG human glioblastoma cell lines. The proliferation rate was assessed in monolayer cultures. In addition, a growth assay, a migration assay, an apoptosis assay, and a tumor invasion assay were performed in a three-dimensional spheroid culture system. NS-398 was able to reduce the proliferation of monolayer cell cultures, as well as the growth of spheroids and tumor cell migration, in a dose-dependent manner. There was also a moderate increase in the number of apoptotic cells in the treated spheroids. NS-398 did not have an inhibitory effect on tumor invasion in the coculture spheroid system. Our study provides evidence that COX-2 is up-regulated in the majority of high-grade gliomas and that a potential role of COX-2 inhibitors as an adjuvant therapy for brain tumors may exist.

Anti-angiogenic treatment strategies for malignant brain tumors.

The use of angiogenesis inhibitors may offer novel strategies in brain tumor therapy. In contrast to traditional cancer treatments that attack tumor cells directly, angiogenesis inhibitors target at the formation of tumor-feeding blood vessels that provide continuous supply of nutrients and oxygen. With respect to brain tumor therapy, inhibitors of angiogenesis display unique features that are unknown to conventional chemotherapeutic agents. The most important features are independence of the blood-brain barrier, cell type specificity, and reduced resistance. Malignant brain tumors, especially malignant gliomas, are among the most vascularized tumors known. Despite multimodal therapeutic approaches, the prognosis remains dismal. Thus, angiogenesis inhibitors may be highly effective drugs against these tumors. In a clinical setting, they could be applied in the treatment of multiple tumors or postsurgically as an adjuvant therapy to prevent recurrence. This article provides an overview of current anti-angiogenic treatment strategies with emphasis on substances already in clinical trials or candidate substances for clinical trials. The cellular and molecular basis of these substances is reviewed.

Craniotomy under local anesthesia and monitored conscious sedation for the resection of tumors involving eloquent cortex.

OBJECTIVE: Resection or even biopsy of an intra-axial mass lesion in close relationship to eloquent cortex carries a major risk of neurological deficit. We have assessed the safety and effectiveness of craniotomy under local anesthesia and monitored conscious sedation for the resection of tumors involving eloquent cortex. METHODS: We have performed a retrospective review of a consecutive series of 157 adult patients who underwent craniotomy under local anesthesia by one surgeon (P.M.B.) at Brigham and Women's Hospital in Boston. All patients had tumors in close proximity to eloquent cortex, including speech, motor, primary sensory, or visual cortex. In most cases the lesion was considered inoperable by the referring surgeon. All resection was verified by post-operative imaging approximately one month after surgery and all cases were reviewed by an independent neurosurgeon (A.D.). RESULTS: In 122 cases, brain mapping was performed to identify eloquent cortex and in the remainder neurological monitoring was maintained during the procedure. Radiological gross total resection was achieved in 57% of patients and greater than 80% resection was achieved in 23%. Thus 4 out of 5 of patients had major resection despite the close relationship of tumor to eloquent cortex. In 13%, less than 80% of tumor was removed because of danger of neurological deficit. In 7% of patients, only a biopsy could be done because of infiltration into eloquent cortex that could only be assessed at surgery. In 76 patients with pre-operative neurological deficits, there was complete resolution of these deficits in 33%, improvement in 32%, no change in 28%, and long-term worsening in 8%. Among 81 patients with no pre-operative neurological deficit, 1 patient suffered a major permanent neurological deficit, and 2 developed minor deficits. There was a transient post-operative deficit in one-third of cases, but this had resolved at one month in all but three patients. Monitored conscious sedation was performed without anesthetic complications using midazolam, sufentanyl and fentanyl with or without propofol. Only one case needed to be converted to general anesthesia. Patient satisfaction with the procedure has been good. Operating time and hospital stay were lower than the mean for brain tumor craniotomy at this hospital. CONCLUSIONS: Tumor surgery with conscious sedation is a safe technique that allows maximal resection of lesions in close anatomical relationship to eloquent cortex, with a low risk of new neurological deficit. Only 7% of intrinsic cortical tumors were ineligible for partial or complete resection with this technique.

Interventional and intraoperative magnetic resonance imaging.

The goal of the Image Guided Therapy Program, as the name implies, is to develop the use of imaging to guide minimally invasive therapy. The program combines interventional and intraoperative magnetic resonance imaging (MRI) with high-performance computing and novel therapeutic devices. In clinical practice the multidisciplinary program provides for the investigation of a wide range of interventional and surgical procedures. The Signa SP 0.5 T superconducting MRI system (GE Medical Systems, Milwaukee, WI) has a 56-cm-wide vertical gap, allowing access to the patient and permitting the execution of interactive MRI-guided procedures. This system is integrated with an optical tracking system and utilizes flexible surface coils and MRI-compatible displays to facilitate procedures. Images are obtained with routine pulse sequences. Nearly real-time imaging, with fast gradient-recalled echo sequences, may be acquired at a rate of one image every 1.5 s with interactive image plane selection. Since 1994, more than 800 of these procedures, including various percutaneous procedures and open surgeries, have been successfully performed at Brigham and Women's Hospital (Boston, MA).

Cell-based and animal models for hepatitis B and C viruses.

Reliable cell-based assays and animal models have been developed for evaluating agents against hepatitis B virus. Although much progress has been made, in vitro and in vivo assays for hepatitis C virus are still on the horizon. Advances towards establishing inexpensive and reliable experimental models have accelerated the development of therapeutic modalities for these life-threatening viral infections. The characterization of well-defined viral targets coupled with improved molecular diagnostic technologies have illuminated this field.

Patient tolerance of craniotomy performed with the patient under local anesthesia and monitored conscious sedation.

OBJECTIVE: Craniotomy and brain mapping performed with the patient under local anesthesia and monitored sedation is an important technique to allow optimal resection of brain tumors or other lesions in close apposition to eloquent cortex. The subjective experience of patients undergoing this procedure has not been addressed in the literature. METHODS: This study formally, intensively, and prospectively assessed the subjective experience of 21 consecutive patients undergoing this procedure. Assessment involved structured interviews at 2 to 3 days postoperatively by a member of the surgical team and at 1 month postoperatively by a psychiatrist, supplemented by pre- and postoperative assessments of the patients' moods using the brief Profile of Mood States questionnaire. RESULTS: At the 1-month interview, all patients were entirely comfortable with the experience and there were no indications of adverse psychological sequelae of the event. In the early postoperative interview, approximately one-half of the patients reported that the experience was entirely satisfactory, without any intraoperative discomfort or pain. One-third of the patients recalled minor difficulties at some stage of the experience, and one-fifth recalled moderate difficulties. An operating room score was devised to quantify the data. Minor technical changes are suggested to improve the patients' subjective experience. CONCLUSIONS: This series confirmed that this technique is a very useful and safe technique for resection of lesions involving eloquent cortex that might otherwise be considered inoperable. This procedure involves a level of stress that remains within the tolerance level of the average adult.

Dietary fat and asthma: is there a connection?

The last two decades have seen an increase in the prevalence of asthma, eczema, and allergic rhinitis in developed countries. This increase has been paralleled by a fall in the consumption of saturated fat and an increase in the amount of polyunsaturated fat in the diet. This is due to a reduction in the consumption of animal fat and an increase in the use of margarine and vegetable oils containing omega-6 polyunsaturated fatty acids (PUFAs), such as linoleic acid. There is also evidence for a decrease in the consumption of oily fish which contain omega-3 PUFAs, such as eicosapentaenoic acid. In a number of countries, there are social class and regional differences in the prevalence of allergic disease, which are associated with differences in the consumption of PUFAs. Linoleic acid is a precursor of arachidonic acid, which can be converted to prostaglandin E2 (PGE2), whereas eicosapentaenoic acid inhibits the formation of PGE2. PGE2 acts on T-lymphocytes to reduce the formation of interferon-gamma (IFN-gamma) without affecting the formation of interleukin-4 (IL-4). This may lead to the development of allergic sensitization, since IL-4 promotes the synthesis of immunoglobulin E (IgE), whereas IFN-gamma has the opposite effect. Changes in the diet may explain the increase in the prevalence of asthma, eczema and allergic rhinitis. The effects of diet may be mediated through an increase in the synthesis of prostaglandin E2 which in turn can promote the formation of immunoglobulin E.

Thermoradiotherapy for brain tumors. Three cases of recurrent malignant astrocytoma and review of clinical experience.

Three patients with symptomatic, recurrent supratentorial malignant astrocytoma were retreated with combined interstitial iridium-192 brachytherapy (RT) and hyperthermia (HT): 50 Gy at 50 cGy/h was delivered 10 mm outside the computed tomography (CT) enhancement border through stereotactically placed plastic tubes, and 915-MHz microwave antenna heating was done for 60 min within 30 min either before or after irradiation. Invasive thermometry data were obtained from the tumor and adjacent brain tissue. The patients tolerated the treatment well and two thirds improved. All patients developed cerebral edema, one also developed scalp infection, and another patient developed meningeal infection. Exceeding the expectancy without treatment, overall survival was 7, 12, and 15 months. On autopsy, two of the patients' brains revealed no active tumor in the treated regions, but one displayed tumor in untreated parts. The HT-RT treatment was very effective, but the original tumor extent was not apparent by the CT imaging technique. A postimplant resection approach may be advisable to minimize postimplant edema. Our data are in agreement with the available literature on more than 400 patients. However, our aim of extending survival decisively could not be realized.

Anesthesia for stereotactic radiosurgery in children.

The development of stereotactic radiosurgery has been a major advance in the treatment of intracranial lesions. By using a stereotactic head frame attached to the skull, large doses of radiation can be delivered precisely to the lesion while sparing surrounding tissues. Although adults can usually undergo this procedure with local anesthesia or conscious sedation alone, children frequently require general anesthesia. This report describes our experience with the anesthetic management of all children who have received this therapy at our institution since the inception of our stereotactic radiosurgery program in 1986 through June 1993. Sixty-eight radiosurgery procedures were performed in 65 patients. Anesthesia time averaged 9.2 h (range, 7-15). Twenty-two patients (ages 11-17; mean 14.3) received local anesthesia alone, two patients (ages 11 and 15) received local anesthesia plus i.v. sedation, and 44 patients (ages 2-14; mean, 7.3) received general anesthesia. Four potentially serious anesthesia-related events occurred; in one child (age 7) receiving general anesthesia, an endotracheal tube obstruction developed during radiosurgery requiring rapid reintubation while the child was still in the head frame; another (age 7) who was undergoing chemotherapy and had neutropenia and rhinitis had a lobar collapse while intubated, requiring mechanical ventilation and endotracheal tube suctioning for lung expansion. Another (age 5) with a recent upper respiratory tract infection had copious endotracheal secretions and sinusitis (ethmoid and maxillary) noted on initial computed tomography scanning and was given antibiotics and decongestants (following nasotracheal extubation), and another (age 15) receiving sedation without endotracheal intubation vomited an undigested meal midway through the procedure while her head was partially immobilized in the head frame.(ABSTRACT TRUNCATED AT 250 WORDS)

Stoma care: finding the most appropriate appliance.

Over the last 25 years a wide range of stoma appliances have become available via the Drug Tarriff because of the post-war development of plastics. Before deciding which is the most appropriate appliance for the stoma patient to use, it is important to carry out an holistic assessment and understand which type of stoma bag is correct for the appropriate stoma.

Central nervous system-immune system interactions: psychoneuroendocrinology of stress and its immune consequences.

Psychoneuroimmunology is a relatively new discipline which deals with CNS-immune system interactions. The evidence for such interactions was reviewed, as was the neuroendocrinologic response to stress. Recent evidence indicates that the behavioral, nervous system, and neuroendocrine responses to stress are mediated by hypothalamic CRF, which acts on both the sympathetic nervous system and the HPA axis, resulting in increased levels of corticosteroids, catecholamines, and certain opiates, substances which are generally immunosuppressive. Concentrations of growth hormone and prolactin, which are immunoenhancing, are elevated early during the response to stress but are later suppressed. Although several other neuromediators may also be released with stress, the net effect of a variety of acute stressors is down regulation of the immune system function. In the following minireview, I consider whether stress alters the resistance of the host to infection as well as the immunomodulatory effects of released immune system mediators on the brain.

Present and future applications of lasers in neurosurgery.

The applications of laser in both adults and pediatric neurosurgery are being steadily refined today. For many routine tumor removals, contemporary lasers do not add to ultrasonic aspiration or suction resection. However, there are some tumors in which one CO2 laser is invaluable; brain stem astrocytomas, skull base tumors, and intraspinal tumors are examples. Similarly, in resections of spinal lipomas they are useful to vaporize lipomas from the roots. Laser welding of vessels is technically possible but has generally not been useful. Perhaps the most exciting application is a combination of laser energy transfer with stereotactic technology. The MRI can be used to visualize structural changes in cerebral tissue. We have used this technology in 40 rats with gliomas and have been able to demonstrate destruction.

Management of asthma in pregnancy.

1. Approximately a third of mothers find their asthma improves during pregnancy, while one third stay the same and the remainder's asthma worsens. 2. Asthma needs to be controlled; if it is not, the fetus may receive insufficient oxygen. 3. The two main types of asthma arise from different causes and have different patterns of inheritance, although in many cases the originating stimulus is the same. 4. A polluted environment contributes to the production of allergens and irritants which trigger asthma in susceptible people.