Cell surface hydrophobicity, adherence to HeLa cell cultures and haemagglutination pattern of pyelonephritogenic Escherichia coli strains

Cell surface hydrophobicity, haemagglutination pattern and adherence to HeLa cells were examined in 230 strains of Escherichia coli collected from women (n = 61 strains) and children (n = 65 strains) with non-obstructive acute pyelonephritis and in 104 faecal control strains of E. coli from healthy adults (n = 71 strains) and children (n = 33 strains). Pyelonephritogenic E. coli strains showed a significantly increased incidence of hydrophobic properties (90%) and mannose resistant haemagglutination (MRHA) of human erythrocytes (83%) than faecal control strains (64 and 23% respectively, P less than 0.001 in both cases). Mannose sensitive haemagglutination (MSHA) was observed in 48% of the pyelonephritogenic E. coli strains and in 50% of the faecal control strains (NS). The incidence of adherence to HeLa cells was low both in pyelonephritogenic and faecal control strains, 6 and 7% respectively (NS). The bacterial phenotypes MRHA + MSHA + and MRHA + MSHA- appeared significantly more often in pyelonephritogenic E. coli strains (35 and 48% respectively) than in faecal control strains (5 and 17% respectively, P less than 0.001 in both cases). The phenotype MRHA- MSHA + occurred significantly more often in control strains (45%) than in pyelonephritogenic strains (13%, P less than 0.001). Eighty-three per cent of the pyelonephritogenic E. coli strains expressing hydrophobic properties showed MRHA and 50% of the hydrophobic strains showed MSHA. There were no significant correlations between cell surface hydrophobic properties and haemagglutination pattern or adherence to HeLa cells in pyelonephritogenic E. coli strains nor in faecal control strains.     

High-Temperature Short-Time Heat Inactivation of HIV and Other Viruses in Human Blood Plasma

An ultra-short-time heating system was used to process blood plasma spiked with various viruses (HIV, vesicular stomatitis virus, encephalomyocarditis virus). Virus reduction and recovery of plasma proteins were measured at various temperatures from 65 to 85 degrees C. Processing at 77 degrees C and 0.006 s resulted in a high level of virus kill, including greater than or equal to 4.4 log10 HIV, while maintaining protein structure and activity essentially intact.     

Paramecium calcium channels are blocked by a family of calmodulin antagonists.

Although the voltage-sensitive Ca channel present in Paramecium has been subjected to detailed physiological and genetic analysis, no organic ligands have been described that block this channel with high affinity and that ultimately can be used to identify channel components. Based on a previous observation that the naphthalene sulfonamide calmodulin antagonist W-7 can block Paramecium Ca channels at high concentration, we have synthesized analogs of W-7 that block these channels at concentrations of less than 1 microM. The effectiveness of these compounds was tested both by a sensitive behavioral assay and on Ca channels that had been incorporated into planar lipid bilayers. Despite the fact that these compounds are effective Paramecium calmodulin antagonists, two independent lines of evidence suggest that W-7 and its analogs block the Ca channel by a mechanism that is independent of their action on calmodulin. In addition, the sensitivity to W-7 or dihydropyridines of Ca channels present in a number of eukaryotic phyla has been used to identify similarities in Ca channels from widely diverse organisms. It appears that the pharmacological specificity provides a means to group Ca channels.     

Use of somatosensory evoked potentials to detect peripheral ischemia and potential injury resulting from positioning of the surgical patient: case reports and discussion.

BACKGROUND: Somatosensory evoked potentials (SSEPs) have long been recognized as an excellent tool for detecting neural and vascular compromise during vascular, neurosurgical and orthopedic procedures. SSEPs have the ability to localize, central versus peripheral, the area of compromise. Many surgeons use only lower-limb SSEP monitoring when performing lumbar spinal surgery. The upper extremities are usually not monitored during such procedures, and monitoring oxygen saturation does not detect neural compromise. PURPOSE: To report that the expanded use of SSEP monitoring during surgery can be beneficial in detecting peripheral ischemia or neural compromise resulting from positioning. STUDY DESIGN: Three case reviews of orthopedic spine surgeries where SSEP monitoring provided early warnings of vascular and neural compression. METHODS: The cases review three different lumbar procedures in which evidence of peripheral ischemia and nerve compression were detected by SSEP monitoring. RESULTS: By the use of upper- and lower-extremity monitoring during lumbar procedures, early detection of ischemia and nerve compression were noted intraoperatively. These changes prompted examination of the patient and repositioning to correct the ischemia or compression. The repositioning in these cases corrected the problem, and no lasting effects were found. CONCLUSIONS: Including SSEP monitoring of the bilateral upper extremities should be considered during lumbar spinal procedures. Such monitoring can be offered for a slightly increased expense and only minimal time delay to place the additional required electrodes by the technician. As a direct result of the early warning of the SSEP monitoring, we were able to avoid potential ischemic injuries and improve patient outcomes.     

Subarachnoid injection as a complication of retrobulbar anesthesia

We studied eight cases of apparent subarachnoid injection of local anesthetic through the optic nerve sheath and subsequent spread to the parabrainstem cisterns and the contralateral optic nerve sheath. The patients all experienced bilateral decrease in vision and ophthalmoplegia, and variable degrees of central nervous system symptoms and respiratory depression. The complications occurred with a variety of local anesthetic agents and with sharp disposable needles in six of the eight cases. These cases demonstrated the spectrum of signs and symptoms that may follow optic nerve sheath injection of local anesthetic agents.     

Association of diurnal variations in hypothalamic but not cortical opiate ([3H]-naloxone)-binding sites with the ability of naloxone to induce LH release in the prepubertal female rat

We report the existence of a diurnal variation in the binding of the opiate antagonist [3H]-naloxone to slices of the mediobasal hypothalamus from prepubertal female rats. The binding is highest in the early morning and reaches a nadir in the late afternoon. Opiate binding in cortical slices from such animals is constant over the course of the day. Changes in receptor density, and not in receptor affinity, account for the diurnal variation in the amount of ligand bound. These diurnal variations in receptor numbers are associated with changes in the ability of naloxone to release LH and may be crucial in the transition from the juvenile state to one of competent reproductive functioning.     

Evaluation of the debonding characteristics of 2 ceramic brackets: an in vitro study.

The objectives of this study were to evaluate and compare the shear bond strengths and bond failure locations of 2 currently available orthodontic ceramic brackets. Forty polycrystalline ceramic brackets (Clarity, 3M Unitek, Monrovia, Calif) and 40 monocrystalline ceramic brackets (Inspire, Ormco, Orange, Calif) were bonded to 80 extracted premolars with the same bonding system. All bonded specimens were placed in distilled water for 42 hours at 37 degrees C followed by thermal cycling for 700 complete cycles. Forty ceramic brackets, 20 of each type, were tested on a universal testing machine to determine the shear force levels required to debond them. Forty ceramic brackets were removed with the debonding pliers recommended by the manufacturers. All teeth were examined under an optical microscope, and the adhesive remnant index was used to assess the bond failure locations. The mean shear bond strength of the Clarity brackets was 21.67 +/- 5.19 MPa, and the mean shear bond strength of the Inspire brackets was 20.32 +/- 8 MPa. The mean shear bond strengths of both brackets were higher than those considered clinically optimal. Most of the brackets (85% of Clarity and 75% of Inspire) tested on the machine failed at the bracket-adhesive interface. One premolar bonded with an Inspire bracket had enamel fracture upon debonding. Most of the brackets (90% of Clarity and 95% of Inspire) debonded with pliers failed at the bracket-adhesive interface. No enamel damage was evident in any specimen when the brackets were removed with the appropriate pliers. The results indicate that the safest way to remove ceramic brackets with respect to reducing the chance of enamel damage is to use the debonding technique specifically designed for each.     

Long-term follow-up and the role of surgery in adolescents with morbid obesity

PURPOSE: Obesity has become a health-care crisis in the United States. Adolescent obesity is now one of the most common childhood disorders, with 4.7 million American adolescents having a body mass index (BMI) greater than the 95th percentile. Most patients do not respond to diet modification or exercise programs and attention is now turning toward surgery as a source of weight loss in adolescents. Few studies have looked at the overall morbidity and mortality of weight loss surgery in this patient population. METHODS: This is a retrospective study of medical charts of 15 bariatric surgical procedures performed on 14 adolescents without known genetic syndromes associated with severe childhood obesity from 1971 to 2001 at the University of Minnesota. Procedures performed on these patients included vertical banded gastroplasty (n = 7), Roux-en-Y gastric bypass (n = 5), and jejunoileal bypass (n = 3). Jejunoileal bypass procedures were performed from 1971 to 1977, after which time this procedure was abandoned. Patient age ranged from 13 to 17 years (mean, 15.7 years). Mean follow-up time was 6 years, with 9 patients available for long-term follow-up. RESULTS: All procedures were performed using an open technique by 1 surgeon. There were no perioperative deaths; complications included 1 case of wound infection, 2 episodes of dumping syndrome that resolved without revision, 1 episode of hypoglycemia, and 1 case of short-term electrolyte imbalance in a patient who underwent jejunoileal bypass. The average BMI dropped from 58.5 +/- 13.7 to 32.1 +/- 9.7 kg/m(2) (P < .01)--a 45% reduction. CONCLUSIONS: Surgery for morbid obesity is safe and results in significant weight loss in adolescents who fail medical therapy.