Facial trauma and associated brain damage

CT continues to be the most important diagnostic study for detection and classification of maxillofacial injury. MR has a complementary role in specific situations because of its multiplanar imaging capabilities and exquisite soft tissue contrast resolution. MR is particularly useful for evaluation of orbital "blow-out" fractures, intraorbital and intraocular hemorrhage, traumatic vascular injuries, and associated intracranial damage.     

Human ovarian granulosa cells and follicular fluid indices: the relationship to oocyte maturity and fertilization in vitro

The study investigates the correlation between oocyte maturity and fertilization and a variety of hormonal parameters in follicular fluid and ovarian granulosa cells. A methodology for purification of granulosa cells from contaminating blood cells is also established. A total of 63 follicular aspirates were collected at oocyte retrieval from 30 women superovulated using the long luteinizing hormone- releasing hormone (LHRH analogue)/human menopausal gonadotrophin regimen. Oestradiol, progesterone, testosterone and human chorionic gonadotrophin (HCG) were quantified in follicular fluid and granulosa cells were immunostained for human chorionic gonadotrophin. Immunopurification of granulosa cells from contaminating blood cells was performed. HCG in follicular fluid was significantly high in follicles yielding immature (grade 3) oocytes (P=0.002); there was no correlation with fertilization. Aspirates from follicles containing mature (grade 1) oocytes and oocytes that subsequently fertilized had significantly more granulosa cells immunobound to HCG (P < 0.001, P=0.02). Moreover, the immunomagnetic purification technique provided >98% pure population of granulosa cells. The data demonstrate that HCG in follicular fluid and on granulosa cells may help to predict oocyte maturity and fertilization. Furthermore, immunomagnetic beads provide a reliable procedure for the purification of ovarian granulosa cells.      

An improved technique for monitoring the drinking behavior of mice

A set of calibrated lickometers provides continuous, quantitative monitoring of fluid consumption. It has been used in our laboratory at four levels of temporal resolution: 24 hr, 1 hr, 6 min, and for counting of individual licks. Convenient features are mounting of the licking tube-bottle assembly on the cage top (which permits the use of disposable plastic cages with litter) and automated collection of data with microcomputers.     

House dust mite allergen avoidance and self-management in allergic patients with asthma: randomised controlled trial

BACKGROUND: The efficacy of bed covers that are impermeable to house dust mites has been disputed. AIM: The aim of the present study was to investigate whether the combination of 'house dust mite impermeable' covers and a self-management plan, based on peak flow values and symptoms, leads to reduced use of inhaled corticosteroids (ICS) than self-management alone. DESIGN OF STUDY: Prospective, randomised, double blind, placebo-controlled trial. SETTING: Primary care in a south-eastern region of the Netherlands. METHOD: Asthma patients aged between 16 and 60 years with a house dust mite allergy requiring ICS were randomised to intervention and placebo groups. They were trained to use a self-management plan based on peak flow and symptoms. After a 3-month training period, the intervention commenced using house dust mite impermeable and placebo bed covers. The follow-up period was 2 years. Primary outcome was the use of ICS; secondary outcomes were peak expiratory flow parameters, asthma control, and symptoms. RESULTS: One hundred and twenty-six patients started the intervention with house dust mite impermeable or placebo bed covers. After 1 and 2 years, significant differences in allergen exposure were found between the intervention and control groups (P<0.001). No significant difference between the intervention and control groups was found in the dose of ICS (P = 0.08), morning peak flow (P = 0.52), peak flow variability (P = 0.36), dyspnoea (P = 0.46), wheezing (P = 0.77), or coughing (P = 0.41). There was no difference in asthma control between the intervention and control groups. CONCLUSION: House dust mite impermeable bed covers combined with self-management do not lead to reduced use of ICS compared with self-management alone.     

Analysis of functional epitopes on the dengue 2 envelope (E) protein using monoclonal IgM antibodies

Summary Forty-two hybridomas secreting IgM antibody against dengue virus were derived from spleen cells of dengue 2 infected mice. Antibody from 27 of these recognised the E protein of this virus. Of the 22 antibodies which neutralised dengue 2, only two cross-reacted with other flaviviruses. These 22 antibodies recognised three discrete domains on dengue virions. Competitive binding studies with IgG monoclonal antibodies suggested that two of the three domains were recognised by both IgG and IgM antibodies and that there were two additional domains which may be recognised exclusively by either IgG or IgM antibodies. IgM antibodies reacting with domains recognised by IgG antibodies that enhanced infection of susceptible cells by dengue 2, had no enhancing properties. None of the IgM antibodies activated the serum complement system after reacting with dengue 2 virions.     

Use of recombinant fusion proteins and monoclonal antibodies to define linear and discontinuous antigenic sites on the dengue virus envelope glycoprotein.

Sixteen overlapping fragments of the dengue-2 virus envelope (E) protein, expressed as trpE-E fusion products in Escherichia coli, were used to map the epitopes defined by a panel of 20 monoclonal antibodies (MAbs) by immunoblotting. Using this technique, the amino acid sequence of six antigenic domains on the E protein was characterized. Nonneutralizing MAbs were found to define either linear-specific, subcomplex-specific (amino acids 22-58), and complex-specific (amino acids 304-332) epitopes or a subcomplex conformational-dependent epitope requiring the presence of two closely linked amino acid sequences from the E protein, 60-97 and 298-397. Neutralizing MAbs, however, defined either group-reactive epitopes present on two overlapping domains (amino acids 60-135; amino acids 60-205) or type-, subcomplex-, complex-, subgroup-, and group-specific determinants (amino acids 298-397). These neutralizing epitopes were all found to be dependent upon disulfide bridges. Our results suggest that the maintenance of a topographical arrangement of discontinuous antigenic domains in the flavivirus E-protein is necessary to induce neutralizing and protective antibodies.     

Estradiol and insulin: independent effects on eating and body weight in rats.

The effects of ovariectomy and estradiol replacement were determined in streptozotocin-diabetic female rats maintained on daily injections of protamine zinc insulin. Similar changes in food intake and body weight in these animals and in nondiabetic control animals indicate that the effects of estradiol on these measures are probably not dependent on changes in pancreatic insulin secretion. Acute and chronic insulin challenges in ovariectomized rats maintained on estradiol benzoate, nafoxidine or oil were also examined. The effects of insulin were not attenuated by prior estrogen conditioning, and there was no evidence of insulin resistance. These experiments suggest that the effects of estradiol on body weight and food intake in female rats are not dependent upon altered insulin levels nor attenuation of the effects of insulin. Estradiol may exert its influence on eating and body weight via separate and possibly more direct pathways. The data also are consistent with the suggestion that ovariectomy-induced and hypothalamic obesities are separate phenomena.     

Hoechst staining and exposure to UV laser during flow cytometric sorting does not affect the frequency of detected endogenous DNA nicks in abnormal and normal human spermatozoa

Controlling the sex of offspring by the separation of X and Y chromosome-bearing spermatozoa using flow cytometry has been reported as a clinical technique aiding prevention of X-linked diseases. Although this technique has resulted in several hundred normal births in animals and at least one human birth, there is still concern over its genetic safety due to the involvement of two potentially mutagenic agents: UV light and the fluorochrome dye, Hoechst 33342 (H33342). Human spermatozoa, particularly those considered abnormal, may be more likely to suffer DNA damage following exposure to mutagenic agents, compared with other mammalian species. The stability of normal fresh and decondensed human spermatozoa were examined after exposure to a range of levels of UV and H33342 staining, using an assay that detects endogenous nicks in the DNA of spermatozoa. The stability of abnormal and normal, fresh and frozen-thawed human spermatozoa was examined following UV laser, H33342 staining and flow cytometry treatments utilizing the same assay. There was an increase in the presence of endogenous nicks when spermatozoa were decondensed compared with fresh spermatozoa. There was no increase in the incidence of nicks in any group of spermatozoa after UV and fluorochrome exposure compared with controls without exposure.