Sea lice, Lepeophtheirus salmonis, transfer between wild sympatric adult and juvenile salmon on the north coast of British Columbia, Canada

We examine sea lice, Lepeophtheirus salmonis, on juvenile and adult salmon from the north coast of British Columbia between 2004 and 2006 in an area that does not at present contain salmon farms. There is a pronounced zonation in the abundance of L. salmonis on juvenile pink salmon, Oncorhynchus gorbuscha, in the Skeena and Nass estuaries. Abundances in the proximal and distal zones of these estuaries are 0.01 and 0.05 respectively. The outer zones serve as feeding and staging areas for the pink salmon smolts. Returning Chinook, Oncorhynchus tshawytscha, and coho salmon, Oncorhynchus kisutch, concentrate in these areas. We collected data in 2006 to examine whether L. salmonis on returning adult salmon are an important source of the sea lice that appear on juvenile pink salmon. Nearly all (99%) of the sea lice on returning Chinook and over 80% on coho salmon were L. salmonis. Most of the L. salmonis were motile stages including many ovigerous females. There was a sharp increase in the abundance of sea lice on juvenile pink salmon smolts between May and July 2006 near the sites of adult captures. As there are no salmon farms on the north coast, few sticklebacks, Gasterosteus aculeatus, and very few resident salmonids until later in the summer, it seems that the most important reservoir of L. salmonis under natural conditions is returning adult salmon. This natural source of sea lice results in levels of abundance that are one or two orders of magnitude lower than those observed on juvenile pink salmon in areas with salmon farms such as the Broughton Archipelago.

Ultrasound enhancement of cationic lipid-mediated gene transfer to primary tumors following systemic administration

The impact of a localized application of ultrasound on gene transfer to primary tumors following systemic administration of cationic lipid based transfection complexes was investigated. We have previously shown that systemic administration of DOTMA (N-[(1-(2-3-dioleyloxy) propyl)]-N-N-N-trimethylammonium chloride):cholesterol-based transfection complexes to tumor-bearing mice resulted in expression in the tumor and other tissues, primarily the lungs. Application of ultrasound to the tumor before or after the injection resulted in a significant increase in gene transfer to the tumor with no increase observed in other tissues. The magnitude of increased expression ranged from three- to 270-fold depending upon the DNA dose. The following parameters were optimized for maximal increase: duration of ultrasound application, the time interval between plasmid injection and sonoporation, and plasmid dose. A combination of plasmid quantitation and fluorescence microscopy showed that ultrasound increased tumor uptake of the plasmid and that uptake was limited to the tumor vasculature. Using an IL- 12 expression plasmid, the combination of a single plasmid dose (10 microg) and ultrasound treatment produced significantly higher levels of IL-12 in tumor. This increased expression was sufficient to inhibit tumor growth compared with the control conditions. These data demonstrate the potential application of sonoporation as an effective method for enhancing the expression of systemically administered genes in tumor endothelium for cancer gene therapy.

Optimization of cationic lipid/DNA complexes for systemic gene transfer to tumor lesions

Intravenous (i.v.) administration of cationic lipid N-[( 1-(2-3-dioleyloxy)propyl)]-N-N-N-trimethylammonium chloride (DOTMA)-based transfection complexes in mice with subcutaneous squamous cell tumors yielded plasmid delivery and expression in tumor lesions. The efficiency of gene transfer in tumors was significantly lower than in the lung. This was consistent with low plasmid levels associated with the tumor, suggesting that plasmid delivery to the tumor site was a limiting factor. Lowering the lipid/DNA charge ratio from 5:1 to 0.8:1 (+/-) did not change DNA levels in tumor but significantly reduced DNA levels in lung. However, expression levels were significantly reduced in both tissues at lower lipid/DNA charge ratios. Complexes prepared from small unilamellar liposomes gave significantly lower expression levels in the lungs but similar expression levels in tumors when compared to complexes prepared from larger unilamellar liposomes. The small liposome complexes were better tolerated than large liposome complexes. Varying the cationic lipid to colipid (cholesterol or DOPE) molar ratio from 4: 1 to 1: 1 significantly reduced expression levels in both tumor and lung. Cationic lipid substitution, using a cholesterol cationic lipid, diethyldiamino-carbamyl-cholesterol instead of DOTMA, produced reduced expression in all other tissues except tumor. Incorporation of PEG into preformed transfection complexes reduced DNA delivery to lung, increased circulation half-life, and enhanced DNA delivery to tumor. In a lung metastatic mouse tumor model, where the accessibility of the i.v. administered transfection complexes to tumor lesions should be less challenging, DOTMA: CHOL complexes (4: 1 lipid to colipid molar ratio, 3: 1 +/- lipid to plasmid charge ratio) were preferentially localized in tumor lesions. These data demonstrate that systemic gene transfer to distal tumor sites by lipid/ DNA complexes may be limited by low plasmid delivery. Modifying the chemical surface properties of transfection complexes enhanced both DNA delivery and expression in tumor and is one approach that may overcome limitations.

Synthetic glycopeptide-based delivery systems for systemic gene targeting to hepatocytes

PURPOSE

To design, synthesize, and test synthetic glycopeptide-based delivery systems for gene targeting to hepatocytes by systemic administration.

METHODS

All peptides were synthesized by the solid phase method developed using Fmoc chemistry on a peptide synthesizer. The binding of galactosylated peptides to HepG2 cells and accessibility of the galactose residues on particle surface was demonstrated by a competition assay using 125I-labeled asialoorosomucoid and RCA lectin agglutination assay, respectively. DNA plasmid encoding chloramphenicol acetyl transferase (CAT) gene was complexed with a tri-galactosylated peptide (GM245.3) or tri-galactosylated lipopeptide (GM246.3) in the presence of an endosomolytic peptide (GM225.1) or endosomolytic lipopeptide (GM227.3) to obtain DNA particles of 100-150 nm in size. The plasmid/peptide complexes were added to HepG2 cell cultures or intravenously administered by tail vein injection into normal mice or rats. Plasmid uptake and expression was quantified by qPCR and ELISA, respectively.

RESULTS

Multiple antennary glycopeptides that have the ability to condense and deliver DNA plasmid to hepatocytes were synthesized and complexed with DNA plasmid to obtain colloidally stable DNA/peptide complexes. Addition of DNA/GM245.3/GM225.1 peptide complexes (1:3:1 (-/+/-)) to HepG2 cell cultures yielded CAT expression in transfected cells. The transfection efficiency was significantly reduced in the absence of galactose ligand or removal of endosomolytic peptide. Intravenous administration of DNA/GM245.3 peptide complexes (1:0.5 (-/+)) into the tail vein of normal rats yielded DNA uptake in the liver. Substitution of GM245.3 by galactosylated lipopeptide GM246.3 resulted in more stable DNA particles, and a 10-fold enhancement in liver plasmid uptake. CAT expression was detectable in liver following intravenous administration of DNA/GM246.3 complexes. Addition of endosomolytic lipopeptide GM227.3 into the complexes (DNA/ GM246.3/GM227.3 (1:0.5:1 (-/+/-))) yielded a 5-fold increase in CAT expression. Liver expression was 8-fold and 40-fold higher than lung and spleen, respectively, and localized in the hepatocytes only. The transfection efficiency in liver was enhanced by increasing DNA dose and injection volume. The plasmid uptake and expression in liver using DNA/GM246.3/GM227.3 complexes was 100-200-fold higher than DNA formulated in glucose. Tissue examination and serum biochemistry did not show any adverse effect of the DNA/GM246.3/ GM227.3 (1:0.5:1 (-/+/-)) complexes after intravenous delivery.

CONCLUSIONS

Gene targeting to hepatocytes was achieved by systemic administration of a well-tolerated synthetic glycopeptide-based delivery system. The transfection efficiency of this glycopeptide delivery system was dependent on peptide structure, endosomolytic activity, colloidal particle stability, and injection volume.

Is short stature a handicap? A comparison of the psychosocial functioning of referred and nonreferred children with normal short stature and children with normal stature

OBJECTIVES

Normal short stature (NSS), defined as height below the 5th percentile for age and sex norms that is not due to illness, hormonal deficiency, or part of a dysmorphic syndrome, has been thought to have a deleterious effect on psychosocial functioning based on observations of referred populations. Recent studies of nonreferred children with NSS, however, have demonstrated normal function. This study directly compared the psychosocial functioning of referred children with NSS, nonreferred children with NSS, and children with normal stature.

STUDY DESIGN

Participants, 90 children (46 boys, 44 girls) between 6 and 12 years of age (mean, 9. 6 years), were administered intelligence and achievement tests. Parents and teachers assessed adaptive and problem behaviors. Family adaptability and cohesiveness were measured.

RESULTS

Intelligence and achievement for referred and nonreferred children with NSS were average. Referred children with NSS were reported to have more externalizing behavior problems and poorer social skills than nonreferred children with NSS and children in the control group. Family adaptability and cohesiveness were comparable across groups.

CONCLUSIONS

Children with NSS have normal psychosocial function, and results suggest that externalizing behavior problems, attention problems, and poor social skills in children referred to clinics for NSS are inappropriately attributed to short stature.

Synergistic effect of formulated plasmid and needle-free injection for genetic vaccines

PURPOSE

A plasmid-based gene expression system was complexed with protective, interactive, and non-condensing (PINC) polymer system and administered with Medi-Jector, a needle-free injection device (NFID), to achieve high and sustained levels of antigen-specific antibodies in blood circulation.

METHODS

Human growth hormone (hGH) or bacterial beta-galactosidase gene expression plasmids driven by a cytomegalovirus (CMV) promoter were formulated in saline or complexed with a PINC polymer, polyvinylpyrrolidone (PVP), and intramuscularly or subcutaneously administered into dogs and pigs using a 22-gauge needle or a NFID. The hGH-specific IgG titers in serum were measured by an ELISA. Beta-galactosidase expression was measured in injected muscles by an enzymatic assay or immunohistochemistry. The effect of NFID on DNA stability and topology was assessed by gel electrophoresis.

RESULTS

Intramuscular (i.m.) or subcutaneous (s.c.) injection of a hGH expression plasmid pCMV-hGH (0.05-0.5 mg/kg) in dogs and pigs elicited antigen-specific IgG antibody titers to expressed hGH. With both routes of injection, pDNA delivery by a NFID was superior to pDNA injection by needle. The magnitude of hGH-specific IgG titers with NFID was 15-20-fold higher than needle injection when pDNA was complexed with PVP, and only 3-4-fold higher with pDNA in saline. The transfection efficiency in the injected muscle, as measured by beta-galactosidase expression, following i.m. injection of pCMV-betagalactosidase/PVP, was not significantly different between needle and NFID-injected groups.

CONCLUSIONS

These data demonstrate that the combination of pDNA/ PVP complexes and a NFID act synergistically to achieve high and sustained levels of antigen-specific IgG response to expressed antigen. This gene delivery approach may offer advantage over needle injection of naked DNA for the development of genetic vaccines.

An alternative training approach to clinical supervision: 2

In this, the second of two articles focusing on the issue of training in clinical supervision, the alleged benefits of training students to be supervisees is highlighted. These are: a substantial reduction in training costs and time; a possible standardization of training; the creation of greater equality and intentionality in the working alliance; an increased student awareness and understanding that supervision is for their benefit; the sharing of values, ground rules, terms and aims between the supervisee/supervisor and the organization; a sense of comradeship between peers in a culture that is often described as having a sense of divide and rule; and a greater sense of team cohesion. The development of basic intrapersonal skills (e.g. reflecting on practice, choosing issues, asking for and using help appropriately) in a non-threatening forum is also of great benefit. The authors conclude that an educational model would include both theoretical and experimential components with the theory preceding the clinical supervision experience. Evaluation of this training could be carried out using a methodology similar to that used by Butterworth et al (1997) in evaluating the impact of receiving supervision.

An alternative training approach to clinical supervision: 1

This article, the first of two-parts, introduces a new series on clinical supervision. It focuses on the issues of training in clinical supervision. The practice of clinical supervision is considered by the Chief Nursing Officer of the Department of Health to be fundamental to safeguarding standards, the development of expertise and the delivery of quality care. Clinical supervision allegedly brings significant benefits to clients and clinicians, and recent research has produced both quantitative and qualitative evidence to support this argument. Many trusts have already made attempts to introduce widespread implementation of clinical supervision and most developments are concerned with equipping clinicians to be supervisors not supervisees. This presents several logistical and financial problems, and currently neither the infrastructure nor the culture exist in nursing to facilitate its widespread and effective uptake. The authors argue that an alternative method of tackling this problem would be to train nurses to become supervisees not supervisors. Supervisee training could commence following the first year of the common foundation programme component of diploma and undergraduate nurse education.

Etiology and treatment of fluid retention (hydrops) in Ménière's syndrome

For years low sodium diets have been recommended in the treatment of Ménière's syndrome. Elevated levels of insulin play an important role in sodium retention in renal tubules. Insulin production is stimulated by high carbohydrate diets. Adrenaline, cortisone, and glucagon levels may be increased by stress or food or inhalant allergies, further elevating insulin levels. The end result of prolonged hyperinsulinemia includes vasoconstriction and eventually arterial smooth muscle hypertrophy. Individual susceptibility to Ménière's syndrome may occur as a result of inflammatory changes in the endolymphatic sac or cochlear aqueduct secondary to primary or latent viral infections, thus predisposing to fluid retention. Long term medical treatment of Ménière's should be directed towards preventing sodium retention through sodium restriction and carbohydrate management. Other factors including stress and allergy should also be considered.

Quartz prism sequence for reduction of cubic phase in a mode-locked Ti:Al(2)O(3) laser

A sequence of four quartz prisms can be used to obtain large negative group-velocity dispersion with reasonable prism spacings and a small residual cubic phase. For a given value of the second-order dispersion and assuming minimal prism insertion, the third-order dispersion is 20% less than that of prism pairs that have been used in Ti:Al(2)O(3) lasers. A mode-locked Ti:Al(2)O(3) laser that includes the prism sequence generates pulses with intensity autocorrelations as short as 33 fs. Spectral bandwidths as large as 80 nm can also be obtained. A measurement of the dispersion of the laser shows that the cubic phase is approximately that of the prism sequence and the laser rod.

The anatomy of the facial nerve

The course of the facial nerve from its origin in the human brain-stem to the termination of its end fibers in the muscles of facial expression is reviewed in detail. The relation of the facial nerve to important adjacent structures is emphasized so that the aural surgeon is better prepared to explore in this intricate area.

Anatomic variations and anomalies involving the facial canal

Congenital bony dehiscences in the facial canal result from incomplete closure during development and are observed in approximately 55% of temporal bones. Anomalies involving the facial canal frequently are encountered in malformations of the temporal bone. These anomalies include aberrations of the course of one or all of the segments of the canal; abnormal relation to the oval and round window; bifurcations and trifurcations of the nerve; and associations with dysplasia of the stapes, oval window, external ear canal, and auricle. Rarely, the facial nerve may be hypoplastic or totally absent. Two abnormal vessels occasionally may accompany the facial nerve in the Fallopian canal: a persistent stapedial artery and a persistent lateral capital vein.

Disruption of neostriatal development in rats following perinatal exposure to mild, but chronic carbon monoxide

The vulnerability of the developing neostriatum to mild, but chronic hypoxia was evaluated in weanling rats exposed only in utero or from conception through postnatal day 10 to 0, 75, 150, and 300 ppm carbon monoxide (CO). The exposure conditions produced maternal carboxyhemoglobin (HbCO) levels of about 11, 19, and 27 percent. HbCO levels of 5 percent are maintained by human cigarette smokers while comparable levels in non-smokers average less than 1%. Significant elevations in DNA and the neurotransmitter, dopamine (DA), were observed in the striatum of 21-day-old rats following the combined pre- and neonatal CO exposure. These neurochemical changes were observed 11 days after CO exposure was terminated and, therefore, cannot be interpreted as acute responses to reduced oxygen. These data indicate that the immature neostriatum is altered by even mild hypoxic insults presented during the time of neuronal proliferation and synaptogenesis.

Anatomy of the round window niche

The contributing elements to boundaries of the round window niche are superiorly the tegmen fossula fenestra rotunda (roof support), inferiorly the fustis (depth) and area concamerata, anteriorly the sustentaculum (support) and postis anterior (anterior pillar), and posteriorly the postis posterior (posterior pillar) and the subiculum (underlying supporting structure). Variations in their size and orientation can give rise to significant variability in the overall size and shape of the round window niche.

Insensitivity of Ubiquinone Biosynthesis in Glioblastoma Cells to an Epileptogenic Drug, U18666A

To investigate the perturbation of ubiquinone biosynthesis by a hypocholesterolemic drug, 3 beta-(2-diethylaminoethoxy)androst-5-en-17-one hydrochloride (U18666A), we measured the incorporation of radioactive mevalonate, methionine, tyrosine, and 4-hydroxybenzoic acid into ubiquinone in glioblastoma cells. These four precursors unanimously showed that ubiquinone biosynthesis was not significantly altered by U18666A, which blocked cholesterol biosynthesis at steps beyond mevalonate formation. The fluctuation of the endogenous mevalonate level had little effect on ubiquinone biosynthesis, implying the relative stability of cellular ubiquinone biosynthesis. Furthermore, exogenously added mevalonate did not have an appreciable effect on ubiquinone biosynthesis. The major ubiquinone produced in rat glioblastoma cells was identified as ubiquinone-9. The mevalonate-derived products accumulated in the U18666A-treated cells differed significantly from those reported in a broken cell study, suggesting the existence of delicate mechanisms regulating the formation of cholesterol intermediates.

The extratemporal facial nerve

The extratemporal course of the facial nerve must be completely understood if surgery is required for the removal of parotid and other tumors in the infratemporal space and skull base or if the nerve itself must be exposed when it has been severed. The key to mastering this surgery is to understand the anatomy of the parotid space and its relations to surrounding structures so that the facial nerve can be found during surgery and preserved intact. Tumor masses or scar tissue may distort normal structures and relations to adjacent structures; this must be kept in mind while operating in this complicated anatomic area.

The petromastoid canal

The embryology and anatomy of the petromastoid canal is reviewed. This structure may be responsible for the passage of some infections of the middle ear cleft into the posterior fossa. It also transmits important blood vessels to a portion of the bony labyrinth, to the facial canal, and to the mucosa of the mastoid air cell system.

The facial canal: normal anatomy, variations and anomalies. I. Normal anatomy of the facial canal

Modern otologic surgery revolves around the use of the operating microscope. The surgeon must have a thorough knowledge of all structures in the temporal bone, particularly since surgery may now be directed to areas in its deeper portions. Of concern here is the whereabouts of the facial canal in its complex course through the temporal bone. A detailed descriptive anatomy with emphasis on the relations of the facial canal to adjacent structures is presented. The variations in the course of the facial canal are discussed. The location of dehiscences in the bony canal wall are described. Finally, great stress is laid upon presentation of these anomalies known to us which can occur in the course of the facial nerve through the temporal bone. These anomalies have clinical and surgical significance.

Metabolic management in Menière's disease

Pollution in the bloodstream by abnormal amounts of metabolites (sugar, insulin, triglycerides and cholesterol) over an extended period of time will have an adverse effect upon the small blood vessels: the arterioles, capillaries and venules. If the microcirculation of the inner ear becomes afflicted, it may produce endolymphatic hydrops. Control of blood pollution can usually be achieved by intelligent dietary management; and, in the case of Menière's disease, the clinical relief is gratifying. Carbohydrate and lipid metabolism is complicated. If the new insulin-glucose tolerance test is used, it will detect many more cases of glucose intolerance. Fifty consecutive cases of Menière's disease were studied for abnormal levels of metabolites. Thirty-eight (76 %) of these cases had either an abnormal glucose tolerance test (using the Wilkerson point system) or at least borderline insulin levels: a) abnormal insulin levels, 35 cases; b) borderline insulin values, 3 cases; c) abnormal glucose tolerance with normal insulin values, no cases; d) both normal glucose tolerance and normal insulin production, 12 cases.

Petrosquamosal suture and lamina

The junction of the petrosal and squamosal portions of the temporal lobe has important relationships that are of interest to the otologist. The resultant suture extends from the glaserian fissure across the top of the middle ear cleft and into the mastoid portion of the temporal bone. It may permit quick passage of infection from the middle ear to the middle cranial fossa. The petrosa may override the squama, forcing it down into the tympanum, where it could cause malleus fixation and a conductive type hearing loss. In the mastoid the suture is identifiable on the surface, but in the interior it is represented by the petrosquamosal lamina. The deeper portion in the petrosal portion of the mastoid may be easily overlooked in surgery of the mastoid and may lead to facial nerve injury.

Carcinoma arising in thyroglossal duct remnants

Papillary adenocarcinoma arising in a thyroglossal cyst is described in a 38-year-old man to make a total of 83 cases in the literature. Most cases appear to be benign thyroglossal duct cysts. The malignant nature of the lesion was recognized only after the permanent pathology sections were reviewed. Paillary carcinoma was the most common type of carcinoma arising in thyroglossal duct remnants. Local resection by the Sistrunk method is the standard treatment when the malignancy has not extended beyond the confines of the cyst. The differentiation between a carcinoma arising in a thyroglossal duct remnant and a metastatic papillary carcinoma from an occult primary in the main thyroid gland is discussed.