Effects of chronic exposure to 12‰ saltwater on the endocrine physiology of juvenile American alligator (Alligator mississippiensis).

American alligator (Alligator mississippiensis) habitats are prone to saltwater intrusion following major storms, hurricanes or droughts. Anthropogenic impacts affecting hydrology of freshwater systems may exacerbate saltwater intrusion into freshwater habitats. The endocrine system of alligators is susceptible to changes in the environment but it is currently not known how the crocodilian physiological system responds to environmental stressors such as salinity. Juvenile alligators were exposed to 12‰ saltwater for 5 weeks to determine the effects of chronic exposure to saline environments. Following 5 weeks, plasma levels of hormones [e.g. progesterone, testosterone, estradiol, corticosterone, aldosterone (ALDO), angiotensin II (ANG II)] were quantified using liquid chromatography and tandem mass spectrometry. Compared with freshwater-kept subjects, saltwater-exposed alligators had significantly elevated plasma levels of corticosterone, 11-deoxycortisol, 17α-hydroxyprogesterone, testosterone, 17ß-estradiol, estrone and estriol whereas pregnenolone and ANG II were significantly depressed and ALDO levels were unchanged (slightly depressed). On the one hand, saltwater exposure did not affect gene expression of renal mineralocorticoid and glucorticoid and angiotensin type 1 (AT-1) receptors or morphology of lingual glands. On the other hand, saltwater exposure significantly reduced plasma glucose concentrations whereas parameters diagnostic of perturbed liver function (aspartate aminotransferase and alanine aminotransferase) and kidney function (creatinine and creatine kinase) were significantly elevated. Except for plasma potassium levels (K+), plasma ions Na+ and Cl- were significantly elevated in saltwater alligators. Overall, this study demonstrated significant endocrine and physiological effects in juvenile alligators chronically exposed to a saline environment. Results provide novel insights into the effects of a natural environmental stressor (salinity) on the renin-angiotensin-aldosterone system and steroidogenesis of alligators.

A national dosimetry audit of intraoperative radiotherapy.

OBJECTIVE: National dosimetry audits are a fundamental part of quality assurance in radiotherapy, especially for new techniques. Intraoperative radiotherapy with a compact mobile kilovoltage X-ray source is a novel approach for the treatment of breast and other cancers. All seven current clinical sites in the UK were audited by a single visiting group and set of measurement equipment. METHODS: Measurements of output, isotropy and depth doses were performed using an ion chamber in solid water, thermoluminescent dosemeters and radiochromic film, respectively. RESULTS: The mean difference between measured and planned dose across all centres was -3.2±2.7%. Measured isotropy was within ±3% around the lateral plane of the X-ray source and +11±4% in the forward direction compared with the lateral plane. Measured depth doses were agreed within 5±2% of manufacturer-provided calibration values or a mean gamma index of 97% at a tolerance of 7%/0.5 mm. CONCLUSION: Agreement within measurement uncertainties was found for all three parameters except forward anisotropy, which is unlikely to be clinically significant. Steep dose gradients increase the sensitivity to small variations in positioning, but these tests are practical for use in interdepartmental audits and local baseline comparison. ADVANCES IN KNOWLEDGE: The first UK interdepartmental audit of intraoperative radiotherapy builds confidence in the delivery of this treatment.

Measuring endogenous changes in serotonergic neurotransmission in humans: a [11C]CUMI-101 PET challenge study.

Serotonin (5-HT) neurotransmission is implicated in cognitive and emotional processes and a number of neuropsychiatric disorders. The use of positron emission tomography (PET) to measure ligand displacement has allowed estimation of endogenous dopamine release in the human brain; however, applying this methodology to assess central 5-HT release has proved more challenging. The aim of this study was to assess the sensitivity of a highly selective 5-HT(1A) partial agonist radioligand [(11)C]CUMI-101 to changes in endogenous 5-HT levels induced by an intravenous challenge with the selective 5-HT re-uptake inhibitor (SSRI), citalopram, in healthy human participants. We studied 15 healthy participants who underwent PET scanning in conjunction with [(11)C]CUMI-101 after receiving an intravenous infusion of citalopram 10 mg or placebo in a double-blind, crossover, randomized design. Regional estimates of binding potential (BP(ND)) were obtained by calculating total volumes of distribution (V(T)) for presynaptic dorsal raphe nucleus (DRN) and postsynaptic cortical regions. Relative to placebo, citalopram infusion significantly increased [(11)C]CUMI-101 BP(ND) at postsynaptic 5-HT(1A) receptors in several cortical regions, but there was no change in binding at 5-HT(1A) autoreceptors in the DRN. Across the postsynaptic brain regions, citalopram treatment induced a mean 7% in [(11)C]CUMI-101 BP(ND) (placebo 1.3 (0.2); citalopram 1.4 (0.2); paired t-test P=0.003). The observed increase in postsynaptic [(11)C]CUMI-101 availability identified following acute citalopram administration could be attributable to a decrease in endogenous 5-HT availability in cortical terminal regions, consistent with preclinical animal studies, in which acute administration of SSRIs decreases DRN cell firing through activation of 5-HT(1A) autoreceptors to reduce 5-HT levels in postsynaptic regions. We conclude that [(11)C]CUMI-101 may be sensitive to changes in endogenous 5-HT release in humans.

Reducing pain after dehorning in dairy calves.

We investigated behavioral responses after dehorning and a sham procedure in 20 Holstein calves aged 4 to 8 wk. Calves either received a nonsteroidal antiinflammatory drug (ketoprofen) before dehorning as well as 2 and 7 h after the procedure or were assigned to a control group. All calves received a sedative (xylazine) and local anaesthetic (lidocaine) before dehorning, and responses were scored over 24 h after the procedure. After hot-iron dehorning, calves treated with ketoprofen also demonstrated little head shaking or ear flicking, but control animals demonstrated higher frequencies of these behaviors; both responses peaked 6 h after dehorning. Differences between the treatment groups remained statistically significant until 12 h (head shaking) and 24 h (ear flicking) after dehorning. A low frequency of head rubbing was observed in both treatment groups, but control calves were more frequently observed engaged in this behavior. There was no statistically significant effect of treatment on any of the other behavioral measures. Calves treated with ketoprofen also tended to gain more weight (1.2+/-0.4 kg) during the 24 h after dehorning than did control calves (0.2+/-0.4 kg). There was no effect of treatment on any of the response variables when calves were sham dehorned. These results indicate that ketoprofen mitigates pain after hot-iron dehorning in young dairy calves.

The development of a mental health service patient information management system.

In this paper we describe the development of the Mental Health-Patient Information Management System (MH-PIMS), which is an information management system designed for use in a modern, primarily community-based, mental health service. MH-PIMS is a computerised database which was designed by clinicians and is supported by a case management system and complementary patient record set-together called the Assessment and Care Evaluation (ACE) system. The paper also describes the ACE system. MH-PIMS can generate patient reports of use to case managers and teams in managing their caseloads and is of use to senior clinicians and service managers for audit and strategic planning purposes.

Analysis of p74, a PDV envelope protein of Autographa californica nucleopolyhedrovirus required for occlusion body infectivity in vivo.

In nature, nuclear polyhedrosis viruses (NPV) are transmitted when susceptible insect larvae ingest viral occlusion bodies (OB). These dissociate in the alkaline environment of the midgut and release encapsulated virions (PDV) which bind to midgut epithelial cells and initiate an infection. A previous study showed that expression of the Autographa californica NPV (AcMNPV) p74 gene during replication is essential for the production of infectious OB. A set of p74 deletion and overexpression recombinants was used for the production and screening of monoclonal antibodies, and for an investigation of gross cytopathology and localization of p74. No differences in virus structure or morphogenesis were observed in infected cells when the p74 gene of AcMNPV was deleted, even though the infectivity of OB harvested from the cells was abolished when they were fed to Trichoplusia ni larvae. Mutant OB released virus particles and degraded insect peritrophic membrane as in infections with wild-type virus; in addition, virions purified from mutant OB were infectious when injected into the haemocoel of T. ni larvae. Western blot analysis confirmed that p74 was associated with the PDV and could not be detected in the budded form virion phenotype. The polypeptide was readily degraded by treatment of purified PDV with proteinase K, in the presence and absence of detergent, and could be extracted from PDV by a non-ionic detergent treatment. The data are consistent with p74 being a structural polypeptide of the PDV phenotype, most probably as a component associated with the outside surface of the virion envelope. Its presence is shown to be essential for primary infection of midgut cells of insect larvae.

The validity of self-reported condom use among adolescents.

BACKGROUND: Research and public health interventions designed to reduce the risk of sexually transmitted diseases (STDs) often are based on self-reported condom use. Yet, validation of self-reported condom use, in particular with adolescents, has rarely been described in the literature. METHODS: Baseline data were obtained from 540 adolescents, 13-21 years of age, enrolled in a 1-year longitudinal study of health beliefs, sexual behaviors, and STD acquisition. Of the 445 participants reporting to be sexually active, 404 (90.8%) agreed to a complete physical examination, including a genital examination, with STD screening after completing the self-administered written questionnaire. Participants' written self-report of condom use was compared to histories obtained by clinicians and laboratory diagnosis of acute STDs to assess validity of written self-report. RESULTS: Complete data were available for 321 females and 77 males of whom 52 females and 5 males had laboratory evidence of 63 infections. Although three individuals who had STDs reported to be consistent users of condoms, a significant association (P < 0.05) was found between those who reported more frequent condom use with the last two partners and the absence of STDs. CONCLUSION: In this group of adolescents, self-report of condom use with the last two partners was associated with the absence of an acute STD. This finding suggests that self-reported condom use is a valid indicator of risk for STDs, with implication for those working with adolescents clinically and in research contexts.

PIP: Although most research on sexually transmitted disease (STD) risk behavior surveillance and prevention is based on self-reports of condom use, there have been few attempts to assess the extent to which self-reports accurately reflect true behavior. To validate this methodology, baseline data were obtained from 540 US male and female adolescents 13-21 years of age enrolled in a 1-year longitudinal study of sexual behaviors and STDs. Of the 445 participants who reported they were sexually active, 398 underwent genital examination and STD screening. 52 females and 5 males had laboratory evidence of acute STDs. 15.2% of females and 32.3% of males reported consistent condom use with their most recent sexual partner. Although 3 young people with STDs had reported they were consistent condom users, a significant (p 0.05) inverse association was found between consistency of reported condom use with the last 2 sexual partners and the occurrence of an acute STD. This finding suggests that, even among adolescents, self-reported condom use is a valid indicator of STD risk.

Control of human sperm intracellular pH by cholesterol and its relationship to the response of the acrosome to progesterone.

When incubated in vitro, human sperm gradually become capable of acrosome-reacting in response to the agonist progesterone. Loss of unesterified cholesterol is required for sperm to become responsive to progesterone, but how cholesterol regulates acrosomal responsiveness is unknown. These experiments tested the hypothesis that loss of sperm cholesterol leads to a rise in the intracellular pH (pH(i)) that makes the sperm responsive to progesterone. pH(i) was measured using BCECF (2',7'-bis-(2-carboxyethyl)-5(6)-carboxyfluorescein) in freshly ejaculated sperm (T0 sperm) and in sperm incubated in vitro overnight (T24 sperm). During incubation, pH(i) increased from 6.94 +/- 0.03 to 7.08 +/- 0.01 (mean +/- SEM, n = 4, p < 0.01). Incubating sperm 24 h in medium supplemented with 1 microM cholesterol to prevent loss of sperm cholesterol suppressed the rise of pH(i) (T24C sperm, pH(i) = 6.96 +/- 0.03, n = 4, p = 0.64 compared to T0 sperm). To test whether their lower pH(i) prevents T24C sperm from reacting, we treated T24C sperm with the alkalinizing agents trimethylamine chloride (TMA) or NH4Cl. These agents did cause T24C sperm to respond to progesterone in a dose-dependent fashion, but they also caused a similar increase in the number of reacting T24 sperm. These agents probably do not reverse the inhibiting effects of high cholesterol but rather make responsive a subpopulation of sperm that is present regardless of the cholesterol content. NH4Cl and TMA did not make T0 sperm responsive to progesterone. The acidifying agent sodium propionate did not diminish the response of T24 sperm to progesterone. In summary, pH(i) increases during incubation in vitro in a cholesterol-dependent fashion. Elevated pH(i) alone is probably not sufficient to make sperm acrosomally responsive.

Seasonal branch and fine root growth of juvenile loblolly pine five growing seasons after fertilization.

In 1989, we established two replications of two fertilization treatments in a 10-year-old loblolly pine (Pinus taeda L.) plantation. Between March and September 1993, branch internode and needle fascicle expansion in the upper and lower third of crowns were measured weekly on three south-facing branches of each of four trees, and new root initiation and elongation were measured at 10-day intervals in three vertical rhizotrons per plot. In one replication, soil water content was measured daily. Fertilization significantly increased the expansion of first flush internodes in the upper crown and first flush needle fascicles in the upper and lower crown. New root growth was stimulated by fertilization in the second half of the growing season. The timing of root growth responses to fertilization corresponded to branch phenologies in the upper and lower crown that were conducive to increased basipetal transport of photosynthate. We conclude, therefore, that new root growth was linked to source-sink activities in the crown. Root initiation was greater in the upper than in the lower part of the soil profile; however, as the growing season progressed and water deficit increased, this relationship was reversed. The effect of soil depth on seasonal root growth was closely associated with water availability, suggesting that root initiation deep in the soil profile is critical for the continued production of new roots in environments subjected to short-term, but relatively severe, water deficits.

Determination of SB 216469-S during tablet production using near-infrared reflectance spectroscopy.

A near-infrared method was developed for analyzing SB 216469-S tablets at various stages of tablet processing, particularly after (i) high shear granulation, (ii) lubrication, (iii) core tablet compression, and (iv) aqueous film coating. Tablets with three different drug concentrations ranging from 1.5% (w/w) to 6.0% (w/w) were examined along with a placebo. Similarly, moisture levels during the granulation drying process were measured, along with the thickness of the tablet coating. Tablet identification inside blister packaging for clinical supplies was also demonstrated.

Replication patterns and cytopathology of cells infected with baculoviruses.

CONCLUSION: In vitro studies have contributed greatly to an understanding of viral cytopathology, molecular biology, and pathogenesis. A model of the role of baculoviruses in a host-parasite relationship is developing which reveals the virus as gaining control of many aspects of host cell biology including control of the cell replication machinery (apoptotic response, macromolecular synthesis), the cytoskeletal structure, the nuclear membrane and intranuclear architecture. Baculovirus replication is a collection of independent but inter-related processes which work within the framework of the host cell, with the in vivo goal of maximizing production of progeny virions. Further molecular dissection of baculovirus replication should yield insight into the processes and principles of viral and host regulatory systems, perhaps facilitating development of new generations of high efficiency sub-viral expression vector systems and the development of genetically improved strains of virus safe for field use in ecologically based pest management strategies.

Characterization of the baculovirus Choristoneura fumiferana multicapsid nuclear polyhedrosis virus p10 gene indicates that the polypeptide contains a coiled-coil domain.

The DNA sequence and transcription pattern of the p10 gene from the spruce budworm baculovirus Choristoneura fumiferana multicapsid nuclear polyhedrosis virus (CfMNPV) were analysed. The CfMNPV p10 gene codes for a protein 81 amino acids in length: this is the shortest p10 peptide identified thus far. A novel characteristic of the CfMNPV p10 gene is that it contains tandem late initiation sites (TAAG) having different temporal transcription patterns. Comparative analysis of CfMNPV p10 and the amino acid sequences of other p10 gene products showed that they each appear to have a similar N-terminal structure: an amphipathic alpha-helical terminus which condenses as coiled-coil multimers. Another feature of the p10 N terminus is that the central region of the coiled-coil domain resembles a bend or hairpin loop and could fold into a hairpin or form a bent rod structure. The condensation of p10 monomers to coiled-coil multimers is likely to be a step leading to the formation of p10 fibrous bodies in infected cells.

Identification and characterization of the v-cath gene of the baculovirus, CfMNPV.

The v-cath gene of the Autographa californica multi-nucleocapsid nuclear polyhedrosis virus (AcMNPV) encodes a cathepsin L-like proteinase which plays a role in the liquefaction of host tissues during a viral infection [1]. We have identified a homologous gene in the spruce budworm virus, Choristoneura fumiferana MNPV (CfMNPV). The CfMNPV v-cath gene is 74% identical to AcMNPV v-cath at the nucleotide sequence level and 80% identical at the level of predicted amino acid sequence. Transcription analysis of the CfMNPV v-cath gene revealed that it is expressed late in infection and that transcription initiates within the consensus baculovirus late-promoter motif.

Characterization of v-cath, a cathepsin L-like proteinase expressed by the baculovirus Autographa californica multiple nuclear polyhedrosis virus.

Autographa californica multiple nuclear polyhedrosis virus (AcMNPV) contains a 966 bp ORF that encodes a papain type cysteine proteinase with cathepsin L-like characteristics. Using Western blot analysis of infected cell extracts we showed that v-cath proteinase has 35.5 kDa and 32 kDa precursor forms which are processed to a 27.5 kDa mature form in a manner characteristic of papain and cathepsin L. V-cath proteinase activity was greatest under acidic conditions (pH 5.0) and was reduced in the presence of the cysteine proteinase inhibitors, leupeptin and E64. Urea, a known enhancer of cathepsin L activity, also enhanced v-cath proteinase activity. AcMNPV v-cath proteinase was detected post-mortem in tissues of insects infected with wild-type (wt) virus. Insects infected with a v-cath deletion mutant did not become flaccid after death as is normally observed with wt AcMNPV infections. These findings indicate a link between v-cath activity and degradation of host tissues during virus pathogenesis.

Protective effects of polymer additives on animal cells exposed to rapidly falling liquid films.

The protective effects of polymer additives on insect cells against fluid mechanical damage was investigated in a falling film-flow device. The falling liquid film creates rapidly moving air-liquid interfaces and high fluid shear stress, mimicking the characteristics of a bursting bubble in aerated cell culture. The additives tested included a group of surface-active polymers, (i.e., Pluronic F68, poly(ethylene glycol)s, and Tween 80) and a group of viscosity-enhancing polymers (i.e., dextrans, methyl-cellulose, and (carboxymethyl)cellulose). We found that methylcellulose, which was previously considered a viscosity-enhancing polymer, actually had significant surface-active properties. All of the surface-active polymers exhibited significant protective effects, with Pluronic F68 and the higher molecular weight poly(ethylene glycol), PEG 20M, providing the best protection. In contrast, the viscosity-enhancing polymers, with the exception of methylcellulose, showed little or no protection for insect cells in the film flow. All of the protective polymers had surface-active properties, even though some of them did not change the surface tension in the actual insect cell medium. There was no correlation between the protective effect and the changes in liquid viscosity and surface tension due to the polymer additives. The level of protection was shown to be dependent upon the type of polymer, its concentration in the culture medium, and the polymer molecular weight. We concluded that the mechanism of protection of these surface-active polymers was through interaction of the polymer molecules with the cell plasma membranes: a fast-acting biological mechanism.

Identification of the gp67 gene of a baculovirus pathogenic to the spruce budworm, Choristoneura fumiferana multinucleocapsid nuclear polyhedrosis virus.

The baculovirus gp67 gene encodes a pH-dependent membrane fusion protein and has been identified in both Autographa californica multinucleocapsid nuclear polyhedrosis virus (AcMNPV) and Orygia pseudotsugata MNPV (OpMNPV). We have identified a homologous gene in the spruce budworm virus, Choristoneura fumiferana MNPV (CfMNPV). The CfMNPV gp67 gene is 79% identical to AcMNPV gp67 at the level of nucleotide sequence and 82% identical at the level of predicted amino acid sequence. As with OpMNPV and AcMNPV gp67, the CfMNPV gp67 protein is found exclusively in the budded virus phenotype of the baculovirus.

Predicting the unpredictable: issues for output-based funding in psychiatric services.

In this study a number of important issues relating to diagnosis related groups and psychiatry are highlighted. Retrospective analysis of admissions to a rural psychiatric admission unit was undertaken utilising two differing approaches to statistical analysis. Results revealed that diagnosis alone is not highly predictive of cost. However, when linked to other variables, greater explanation in variation of length of stay was achieved. Data from social variables yielded sufficiently interesting results to warrant further investigation. The authors conclude by reporting the resultant groups from the classification analysis and offer some suggestions for further research.