bluuebunny/crossref_metadata_2025 huggingface dataset:
Paediatric day‐case surgery: an audit of unplanned hospital admission Royal Hospital for Sick Children, Glasgow*
Authors: Blacoe D. A. , Cunning E. , Bell G.
Published: May 2008

Audit of unplanned hospital admission provides information to guide quality improvement measures and is a crude indicator of quality of care in ambulatory surgery. Our objectives were to re‐audit factors relating to this outcome. Previous audit conducted in this unit revealed an unplanned admission rate of 3.7%. Data were collected between April 2000–March 2004. Of 13 592 day surgery patients, 238 (1.8%) unplanned admissions occurred. The admission rate displayed a falling trend and represented a significant improvement over the previous audit (p < 0.001). Unplanned admissions were most commonly caused by nausea/vomiting 23.5% (n = 56), postoperative bleeding 13.9% (n = 34), and unexpected extent/difficulty of procedure 11.8% (n = 28). Of all admissions, 18.5% (n = 44) were following orchidopexy, 16.4% (n = 39) following circumcision, and 12.6% (n = 30) following dental extraction. This audit shows that the unplanned admission rate is low and falling, and compares favourably with other units. Measures have been implemented targeting patients at high risk of admission.
The impact of head position on the cuff and tube tip position of preformed oral tracheal tubes in young children
Authors: Jordi Ritz E.‐M. , Von Ungern‐Sternberg B. S. , Keller K. , Frei F. J. , Erb T. O.
Published: May 2008

Head and neck movements affect both the length of the trachea and the position of tracheal tubes. This is of relevance when using cuffed tubes because changes in the position of the tube tip may not be equal to changes in the position of the cuff. The aim of the study was to assess the impact of head and neck movement on the position of the tube tip and the cuff of newly designed, oral preformed tracheal tubes in children. The tracheas of 128 children aged 1–8 years were intubated with preformed oral tubes. The distances ‘carina‐to‐tracheal tube tip’ and ‘vocal cords‐to‐tube tip’ were measured endoscopically. These measurements were performed with the head and neck in a functional neutral position (110°), during neck flexion (80°) and neck extension (130°). Tracheal length was dependent on head and neck position: neck extension elongated the trachea (p < 0.0001), and neck flexion shortened the trachea (p < 0.0001). Neck flexion moved the tube inward and resulted in endobronchial displacement in two patients. Neck extension moved the tube outwards. While no cuff was positioned between the vocal cords, cuff movement to the cricoid area occurred frequently. Complex interactions during head and neck movement along with the fixed insertion depth of preformed tubes often cause inadvertent malpositioning of the tube tip and cuff. Further changes to tube and cuff lengths might improve the safety of oral preformed tubes in children.
The Pentax‐AWS® rigid indirect video laryngoscope: clinical assessment of performance in 320 cases*
Authors: Suzuki A. , Toyama Y. , Katsumi N. , Kunisawa T. , Sasaki R. , Hirota K. , Henderson J. J. , Iwasaki H.
Published: May 2008

The Pentax‐AWS® airway scope system is a rigid indirect video laryngoscope with integrated tube guidance. Laryngoscopy and intubation are visualised using a built in LCD monitor which displays the view obtained by a CCD camera mounted in the tip of the laryngoscope. We describe its clinical performance in 320 patients. The Pentax‐AWS significantly improved the laryngeal view compared to the Macintosh laryngoscope. Forty‐six patients (14%) who were classified as Cormack Lehane glottic view grade 3 or 4 using the Macintosh laryngoscope were classified as grade 1 (45 cases) or 2a (1 case) using the Pentax‐AWS airway scope. Laryngeal views measured by percentage of glottic opening score were improved significantly using the Pentax‐AWS. Intubation using the Pentax‐AWS was successful in all cases, 96% at the first and 4% at the second attempt. The mean (SD) time required to place the tracheal tube was 20 (10) s. The Cormack Lehane grade obtained with the Macintosh blade did not affect the total time to correctly position the tube using the Pentax‐AWS. Intubation difficulty scale (score = 0 in 305 patients, score = 1 in 14 and score = 2 in one patient) indicates that tracheal intubation was performed easily in most cases. The Pentax‐AWS not only improves the laryngeal view, but its tube guide also facilitates rapid, easy and reliable tracheal intubation under vision. It can be useful in routine anesthesia care and may be advantageous in the situation of unanticipated difficult intubation.
The effect of mannitol on renal function following cardio‐pulmonary bypass in patients with normal pre‐operative creatinine*
Authors: Yallop K. G. , Sheppard S. V. , Smith D. C.
Published: May 2008

Mannitol is often added to the cardiopulmonary bypass pump prime to reduce the incidence of renal dysfunction, but studies so far have been inconclusive. Urinary excretion of microalbumin and retinol binding protein are more sensitive than routine biochemical tests of renal function after cardiac surgery. We performed a double‐blind, randomised, controlled trial in cardiac surgical patients with pre‐operative plasma creatinine < 130 μmol.l−1. Twenty patients received 0.5 g.kg−1 of mannitol in the pump prime, whereas 20 control patients received an equivalent volume of Hartmann’s solution. Blood and urine samples were taken on the day before surgery and daily for 5 days postoperatively for measurement of plasma urea and creatinine, urinary creatinine, retinol binding protein and microalbumin. We found no differences between the mannitol and control patients for any measured variable, and conclude that mannitol has little impact on renal function in patients with normal pre‐operative plasma creatinine concentrations.
Acute passive cigarette smoke exposure and inhaled human insulin (Exubera®) pharmacokinetics
Authors: Fountaine Robert , Milton Ashley , Checchio Tina , Wei Greg , Stolar Marilyn , Teeter John , Jaeger Rudolph , Fryburg David
Published: May 2008

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

• Active cigarette smoking is associated with increased permeability of the pulmonary alveolar epithelium, resulting in faster absorption of inhaled drugs such as Exubera® (EXU). Absorption of EXU is increased approximately twice to four times as much in chronic smokers compared with nonsmokers.

• The rate of clearance of radioaerosols such as technetium‐labelled diethylenetriamine penta‐acetic acid is decreased in response to passive smoke exposure.

WHAT THIS STUDY ADDS

• Passive smoke exposure causes a decrease in lung permeability, an effect opposite to that of active smoking.

• Acute passive smoke exposure results in a decrease in EXU bioavailability and does not create a risk of hypoglycaemia.

• These results are consistent with previous studies of radioaerosol lung clearance.

AIMS

Relative to nonsmokers, the bioavailability of inhaled human insulin (Exubera®; EXU) is markedly increased in chronic smokers. The pharmacokinetics of EXU following passive cigarette smoke exposure is unknown.

METHODS

In an open‐label, crossover study, healthy nonsmoking volunteers received two treatments in randomized sequence separated by a 2‐week wash‐out: (i) EXU 3 mg with no passive smoke exposure and (ii) EXU 3 mg after passive smoke exposure (atmospheric nicotine levels 75–125 μg m−3) for 2 h. Blood samples were obtained at prespecified times up to 6 h after EXU administration.

RESULTS

Twenty‐seven subjects completed both study periods. Mean plasma insulin AUC0−360 decreased by 17% [ratio 83%, 95% confidence interval (CI) 68.8, 99.5] and mean Cmax by 29% (ratio 71%, 95% CI 59.8, 83.1) after passive cigarette smoke exposure. The median (range) tmax was 60 min (20–120 min) and 75 min (20–360 min) in the EXU with no exposure and EXU passive exposure groups, respectively. EXU was well tolerated.

CONCLUSIONS

Unlike active chronic smoking, acute passive cigarette smoke exposure modestly decreases EXU bioavailability and thus should not increase hypoglycaemia risk. These results are consistent with those from published literature involving technetium‐labelled diethylenetriamine penta‐acetic acid and suggest that passive cigarette smoke exposure causes an acute decrease in lung permeability vs. active smoking, which causes an increase in permeability.
Diclofenac readily penetrates the cerebrospinal fluid in children
Authors: Kokki Hannu , Kumpulainen Elina , Laisalmi Merja , Savolainen Jouko , Rautio Jarkko , Lehtonen Marko
Published: May 2008

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

• Diclofenac, a nonselective nonsteroidal anti‐inflammatory drug,, exerts analgesic action both in the peripheral tissues and in the central nervous system by inhibiting cyclooxygenase enzymes COX‐1/2, but central nervous system penetration of diclofenac has not been evaluated in humans.

WHAT THIS STUDY ADDS

• Diclofenac penetrates the cerebrospinal fluid rapidly, and after a single intravenous dose of 1 mg kg−1, sufficient concentrations to inhibit COX‐1/2 are sustained for up to 4 h.

AIMS

The primary aim was to study the cerebrospinal fluid (CSF) penetration of intravenous diclofenac in children. The secondary aim was to evaluate the plasma diclofenac concentration at the onset of wound pain after inguinal surgery in children.

METHODS

A total of 31 children (24 boys) aged 3 months to 12 years received a single intravenous injection of diclofenac 1 mg kg−1. Paired CSF and blood samples were obtained 5 min to 22 h (median 69 min) later. In children having inguinal surgery a second blood sample was obtained at the time that the children felt wound pain for the first time after surgery. Diclofenac concentrations in CSF, plasma and protein free plasma were measured by gas chromatography with mass spectrometric detection.

RESULTS

In the 28 CSF samples obtained at 5 min to 3 h 43 min after injection, diclofenac concentrations ranged between 0.5 and 4.7 μg l−1. At 5.5 h the CSF concentration was 0.1 μg l−1, and no diclofenac was detected in the two CSF samples obtained at 22 h. The median of plasma diclofenac concentration at the time when pain returned after inguinal surgery was 104 μg l−1(range 70–272 μg l−1). No serious or unexpected adverse effects were reported.

CONCLUSIONS

Diclofenac penetrates the CSF rapidly, and a sufficient concentration to inhibit cyclooxygenase enzymes is sustained for up to 4 h.
Venous incompetence, poverty and lactate dehydrogenase in Jamaica are important predictors of leg ulceration in sickle cell anaemia
Authors: Cumming V. , King L. , Fraser R. , Serjeant G. , Reid M.
Published: May 2008

Clinical features and potential risk factors for chronic leg ulceration (duration >6 months) in homozygous sickle cell (SS) disease were examined in 225 subjects in the Jamaican Cohort Study. Potential risk factors included the number of HBA genes, steady state haematology, serum lactate dehydrogenase (LDH), venous incompetence, and socio‐economic status. Chronic ulcers occurred in 53 subjects with the highest risk of ulcer development at 18 years. The prevalence was 29·5% and cumulative incidence 16·7%. Gender or α‐thalassaemia trait did not affect the incidence of leg ulcer. Ulceration was associated with lower haemoglobin, red cell count, fetal haemoglobin, and socio‐economic status and higher reticulocyte count, platelet count, serum LDH and venous incompetence in univariate analyses. Venous incompetence [Hazard Ratio (HR) 3·0–4·0] and socio‐economic status (HR 0·8) were most consistently associated with leg ulceration on multivariate analysis. Regression models incorporating serum LDH suggested this to be a stronger predictor than haematological indices. The prevalence of ulcers at 30% is less than previous estimates in Jamaica, probably reflecting the lack of ascertainment bias in the Cohort Study, and also a real secular decline. In Jamaica, venous incompetence, low socio‐economic status, and high serum LDH were the strongest predictors of chronic ulceration.
MYC translocation in chronic lymphocytic leukaemia is associated with increased prolymphocytes and a poor prognosis
Authors: Huh Yang O. , Lin Katherine I‐Chun , Vega Francisco , Schlette Ellen , Yin C. Cameron , Keating Michael J. , Luthra R. , Medeiros L. Jeffrey , Abruzzo Lynne V.
Published: May 2008

Chromosomal translocations that involve MYC, characteristic of Burkitt lymphoma, are rare in chronic lymphocytic leukaemia (CLL). We report the clinical, morphological, immunophenotypic, cytogenetic and molecular genetic features of eight CLL cases with MYC rearrangement. The patients, five men and three women (median age, 71 years) had bone marrow involvement and an absolute peripheral blood lymphocytosis; five had lymphadenopathy; seven had splenomegaly. Prolymphocytes were increased (≥10%) in all cases. Six cases were classified as CLL with increased prolymphocytes (CLL/PL; prolymphocytes 10–55%), and two were classified as CLL in prolymphocytic transformation (CLL/PT; prolymphocytes >55%). All cases co‐expressed CD5, CD19, and CD23; five of eight expressed ZAP‐70. Of seven cases tested, four had mutated and three had unmutated IGHV genes. Conventional cytogenetic studies demonstrated t(8;14)(q24·1;q32) in five cases, t(8;22)(q24·1;q11) in two cases, and t(2;8)(p12;q24·1) in one case. Seven cases contained additional chromosomal abnormalities. All patients received combination chemotherapy. Two developed Epstein–Barr virus (EBV)‐associated diffuse large B‐cell lymphomas (DLBCL) that were clonally unrelated to the CLL. At follow‐up, two patients are alive, four died of underlying disease, one died of EBV‐associated DLBCL, and one died of an unrelated cancer. In summary, MYC rearrangement, which occurs rarely in CLL patients, is associated with increased prolymphocytes, complex cytogenetic abnormalities, and a poor prognosis.
Hairy cell leukaemia: a heterogeneous disease?
Authors: Dores Graça M. , Matsuno Rayna K. , Weisenburger Dennis D. , Rosenberg Philip S. , Anderson William F.
Published: May 2008

The US National Cancer Institute’s Surveillance, Epidemiology and End Results program was used to develop aetiological clues for hairy cell leukaemia (HCL). Descriptive techniques (age‐adjusted incidence trends, age‐specific incidence rates (IR), and age distributions‐at‐diagnosis) were supplemented with mathematical models (two‐component mixture, generalized linear regression, and age‐period‐cohort). There were 2856 cases of HCL diagnosed during 1978–2004 (IR 0·32/100 000 person‐years). IRs were nearly 4‐fold greater among men than women and more than 3‐fold higher for Whites than Blacks. Temporal trends were stable over time. Age‐specific IRs increased rapidly until approximately 40 years then rose at a slower pace. The age‐specific IR curves reflected bimodal early‐ and late‐onset age distributions‐at‐diagnosis (or density plots), with some variation by gender. Among both men and women, a two‐component mixture model fitted the data better than a single density or cancer population. Age‐period‐cohort models confirmed statistically significant age‐related effects after full adjustment for temporal trends (calendar‐period and birth‐cohort effects). In summary, age incidence patterns (rates and bimodal densities) suggested that HCL is a heterogeneous disease, consisting of at least two underlying subgroups and/or cancer populations by age‐at‐onset. Distinct early‐ and late‐onset HCL populations may reflect different age‐related causal pathways, risk factor profiles, and/or stem cells of origin.
Blood outgrowth endothelial cells from chronic myeloid leukaemia patients are BCR/ABL1 negative
Authors: Otten Jasmin , Schultze Alexander , Schafhausen Philippe , Otterstetter Svenja , Dierlamm Judith , Bokemeyer Carsten , Brummendorf Tim H. , Fiedler Walter , Loges Sonja
Published: May 2008

The existence of adult haemangioblasts with dual haematopoietic and endothelial developmental potential was confirmed after detection of Ph+ vascular endothelial cells in chronic myeloid leukaemia (CML) patients. Blood outgrowth endothelial cells (OECs) from CML patients were found not to harbour the Philadelphia translocation and were thus not clonally related to BRC/ABL1+ hematopoietic progenitors, but comprised a distinct subfraction of endothelial cells. Remarkably, the frequency of CML‐derived OECs was 9‐fold higher as compared to healthy donors (n = 19 and n = 300, respectively; P < 0·0001) and these cells showed increased proliferative potential, possibly reflecting the mobilisation of OEC progenitors by pro‐angiogenic cytokines.
CRTH2‐dependent, STAT6‐independent induction of cedar pollen dermatitis
Authors: Oiwa M. , Satoh T. , Watanabe M. , Niwa H. , Hirai H. , Nakamura M. , Yokozeki H.
Published: May 2008

Background
Airborne contact dermatitis to cedar pollen is a recently identified disease that generally affects individuals with cedar pollinosis of the nasal and/or ocular symptoms, as well as some patients with atopic dermatitis.

Objective
To elucidate the pathological mechanisms of cedar pollen dermatitis.

Methods
We established a mouse model of cedar pollen dermatitis by epicutaneous sensitization with Japanese cedar pollen antigen (Ag).

Results
Histologically, there was marked dermal cellular infiltrate, including eosinophils and mast cells, with epidermal thickening. The induction of dermatitis was accompanied by production of cedar pollen‐specific IgE. In the lesional skin, IL‐13, IL‐18, eotaxin/chemokine (C‐C motif) ligand (CCL) 11, regulated upon activation, normal T cell expressed and secreted/CCL5, macrophage‐derived chemokine/CCL22 and thymus and activation‐regulated chemokine/CCL17, but not IL‐4 and IFN‐γ, were produced. Mast cell‐deficient WBB6F1‐W/Wv mice failed to develop cedar pollen dermatitis, although regional lymph node cells proliferated in response to Cryptomeria japonica (Cry j) 1 and Cry j2 Ags in vitro. Surprisingly, the induction of dermatitis was independent of STAT6/IgE. In contrast, mice deficient in CRTH2, a receptor for prostaglandin D2 (PGD2), showed diminished inflammation. Consistent with this, ramatroban, a CRTH2 antagonist, significantly inhibited inflammatory cell infiltration.

Conclusion
These data suggest that PGD2–CRTH2 signalling contributes to inflammation in cedar pollen dermatitis, and unlike cedar pollinosis of the nasal mucosa, STAT6 is not a therapeutic target for treatment.
Phenotypes of food hypersensitivity and development of allergic diseases during the first 8 years of life
Authors: Östblom E. , Lilja G. , Pershagen G. , Van Hage M. , Wickman M.
Published: May 2008

Background
Longitudinal data from population‐based studies on the development and persistence of food hypersensitivity (FHS) during childhood are almost absent.

Methods
A population‐based birth cohort was established, and information on various exposures and symptoms of allergic disease were obtained from questionnaires when the children were 2 months, 1, 2, 4 and 8 years of age. Complete data were available on 3104 children. Children with reported FHS and doctor's diagnosis of food allergy (RDFA) were identified and allocated into transient, intermittent, late‐onset and persistent phenotypes. Food allergen‐specific IgE‐antibodies (abs) to a mix of six common food allergens (fx5®) were analysed at 4 and 8 years of age in 1857 children.

Results
The overall prevalence of reported FHS in combination with RDFA should be 3.1% at 1 year to 7.6% at 8 years of age. However, reactions to milk, egg, fish and wheat decreased, whereas an increase was seen for peanuts and tree nuts. Reported reactions to egg, peanuts or tree nuts early in life, as well as IgE‐abs to food allergens at the age of 4, increased the risk of FHS at 8 years of age. Furthermore, FHS at young ages increased the risk for asthma, eczema and allergic rhinitis at 8 years of age, even when adjustments were made for children with these symptoms during the first 2 years of life.

Conclusion
The increasing prevalence of FHS up to the age of 8 years probably reflects an increasing prevalence of allergy to birch pollen and pollen‐related reactions to foods. Reactions to egg, peanuts and tree nuts early in life increase the risk of FHS at 8 years. Furthermore, reported FHS at young ages, even though transient, seems to increase the risk for other allergic diseases at 8 years of age.
Renal FNA‐based typing of renal masses remains a useful adjunctive modality: evaluation of 31 renal masses with correlative histology
Authors: Masoom S. , Venkataraman G. , Jensen J. , Flanigan R. C. , Wojcik E. M.
Published: May 2008

Objectives:  Given the advances in renal imaging modalities in the recent years, a greater number of renal cell carcinomas (RCCs) with tumour size of <3 cm are being detected radiologically. Consequently, there is a pressing need for accurate typing of RCCs which, in turn, will aid in selection of cases of nephron‐sparing surgery.

Methods:  A total of 31 cases of renal masses with available fine needle aspiration (FNA) material and concomitant histopathology details were retrieved. They included 27 RCCs (17 clear cells, eight papillary and two chromophobe), one oncocytoma, one liposarcoma and two benign lesions – one xanthogranulomatous pyelonephritis (XPN) and one benign cyst. Two investigators reviewed all FNA material. The degree of concordance between cytological typing and histological typing was assessed.

Results:  There was excellent agreement between the FNA typing and the final diagnosis, with correct classification in 28 of 31 cases. Among the three discordant cases, two were RCCs. The first was a papillary RCC (PRCC) that was misdiagnosed on FNA as clear cell RCC. Another case that was typed as a PRCC on final histopathology was diagnosed ‘suspicious cells’ on FNA. The third case was an XPN that was misdiagnosed on FNA as RCC with necrosis.

Conclusions:  There is an excellent concordance (90.3%) between the FNA diagnosis and the final histological diagnosis, especially in RCCs. There is a tendency for misdiagnosis with PRCC. Lesions with extensive necrosis and relatively insufficient diagnostic material on FNA specimens must be interpreted with caution. Better concordance might be observed with more extensive sampling.
Cytomorphological changes after ultrasound‐guided percutaneous ethanol injection in benign thyroid nodules
Authors: Song D. E. , Kim Y. M. , Gong G.
Published: May 2008

Objective:  To characterize the cytomorphological changes after percutaneous ethanol injection (PEI) in benign thyroid nodules, we compared the cytological features of fine needle aspiration cytology (FNAC) samples before and after PEI.

Methods:  Fifty‐five cases diagnosed with adenomatous goitre (group 1, 35 cases) or cystic changes only (group 2, 20 cases) were included. In all cases, FNACs were performed by the pathologists before and after PEI. PEI was performed in all cases by a diagnostic radiologist according to the ultrasound guidelines. The following cytological features were evaluated by two pathologists: cellularity of follicular epithelial cells, background, cellular pleomorphism, nuclear/cytoplasmic (N/C) ratio, chromatin pattern, presence of nucleoli, macrophages, multinucleated giant cells, and mitosis.

Results:  In group 1, 19 cases (54%) showed changes in cellularity after PEI, with reduced cellularity in 13 cases (37%) and increased cellularity in six cases (17%). No necrotic background was observed before PEI; however, 14 cases (40%) developed necrotic background after PEI (P < 0.0001). Multinucleated giant cells were observed in 18 cases (51%) after PEI, which is in contrast to four cases (11%) before PEI (P = 0.001). In group 2, necrotic background was seen in 11 cases (55%, P < 0.0001) and multinucleated giant cells were observed in four cases (20%) after PEI.

Conclusions:  Necrotic background and presence of multinucleated giant cells are indicative of tissue damage caused by PEI in the FNAC specimens of benign thyroid nodules. In contrast to other modalities including chemotherapy or radiation treatment for malignant tumour, no unusual cytological change is observed after PEI.
Temporal dynamics of freshwater bacterio‐ and virioplankton along a littoral–pelagic gradient
Authors: FILIPPINI MANUELA , BUESING NANNA , GESSNER MARK O.
Published: May 2008

1. Viruses have been identified as an important component of plankton communities but their temporal dynamics remain poorly characterized, especially in littoral zones of lakes. Seasonal and diel dynamics of planktonic viruses and their main hosts (i.e. bacteria) were therefore assessed along four parallel transects of a lake, extending from within a littoral reed stand across the littoral shelf to the pelagic zone.

2. Viral abundance ranged from 1.9 to 9.7 × 107 virus‐like particles (VLP) mL−1 with distinct seasonal peaks in spring at all locations. Seasonal variation in bacterial abundance varied more than 10‐fold (0.85–12 × 106 cells mL−1) and was synchronized with changes in viral abundance. As a result, the ratio of viruses to bacteria (average of 12.5) varied much less over the year.

3. Bacterial production (0.11–0.98 μg C L−1 h−1) and growth rates (0.06–0.85 day−1) also varied seasonally but, in contrast to abundances, high production rates in spring were maintained in mid‐summer, particularly in the reed stand, where growth rates were highest.

4. Variation among locations was small in most measured parameters, probably due to extensive exchange between pelagic and littoral water masses. Nevertheless, average bacterial growth and production rates in all seasons were consistently highest in the reed stand.

5. In the August of an exceptionally warm summer, viral and bacterial abundance varied little over a diel cycle (1.23–1.75 × 108 VLP mL−1 and 0.78–1.90 × 107 cells mL−1, respectively) in spite of a trend towards higher values at night. Diel changes in bacterial production (0.23–0.69 μg C L−1 h−1) and growth rate (0.02–0.06 day−1) were more pronounced, with higher values also occurring during the night, possibly indicating that bacterio‐ and phytoplankton production were not tightly coupled during our diel study.

6. Overall these results indicate that seasonal changes of virio‐ and bacterioplankton were mainly driven by high microbial activity in spring and were more pronounced than either diel changes on a hot summer day or spatial differences at a scale of 10–100 m.
Effects of freshwater and seawater mixing on virio‐ and bacterioplankton in a tropical estuary
Authors: CISSOKO MAÏMOUNA , DESNUES ANNE , BOUVY MARC , SIME‐NGANDO TÉLESPHORE , VERLING EMMA , BETTAREL YVAN
Published: May 2008

1. Estuaries are interesting sites to examine virus–bacteria interactions since they may vary gradually or abruptly in salinity, which presumably requires physiological, genetic and ecological adaptations. To explore such adjustments in tropical areas, freshwater and seawater samples were collected in the estuarine system of the River Senegal and experimentally subjected to abrupt mixing of seawater with freshwater and vice versa.

2. Production rates of freshwater bacteria (measured by the tritiated thymidine incorporation method) and of viruses (measured by the dilution method) sharply declined immediately after seawater addition, which was followed by a spectacular recovery of the surviving bacterial and viral populations within 24 and 48 h, respectively.

3. Conversely, neither marine bacteria nor viruses were significantly affected by mixing with freshwater. This suggests that the turbulent front between ascending tidal sea water and outwelling fluvial freshwater is a more favourable environment for marine bacterioplankton, which may take advantage of massive bursts of freshwater cells resulting from osmotic shock.

4. In both mixing experiments, the dynamics of virioplankton production followed that of the bacteria within 24 h, suggesting that viruses can rapidly respond to dramatic shifts in the abundance and community composition of bacterial hosts.
Evidence for cyanophages active against bloom‐forming freshwater cyanobacteria
Authors: DENG LI , HAYES PAUL K.
Published: May 2008

1. A total of 35 putative cyanophages able to infect non‐axenic cultures of bloom‐forming freshwater cyanobacteria in the genera Microcystis, Anabaena and Planktothrix were isolated from Lake Zurich (Switzerland) and lakes in the Cotswold Water Park (U.K.). Eleven lytic cyanophage isolates were isolated on Microcystis and 12 each on Anabaena and Planktothrix. Cyanophage isolation protocols varied when using these different cyanobacterial hosts.

2. The collection of putative cyanophage isolates encompassed a variety of morphotypes, including the first filamentous cyanophage from any environment and the second siphocyanophage reported from fresh water.

3. PCR primer sets for gp20, gp23 and MCP genes, which have been previously found to be conserved in other cyanophages, were used in an attempt to determine genetic diversity among the phage isolates. The failure to obtain specific amplification products from most isolates suggests that the cyanophages isolated in this study were different from those previously characterized from both marine and freshwater environments.

4. Some putative cyanophages within the collection of isolates proved to have a very broad host range and were able to infect Anabaena, Microcystis and Planktothrix. The ability to infect a wide range of host taxa extends the potential reproductive period for lytic propagation, and also has implications for the transfer of genetic information between deeply separated cyanobacterial lineages.
Freshwater and marine virioplankton: a brief overview of commonalities and differences
Authors: WILHELM STEVEN W. , MATTESON AUDREY R.
Published: May 2008

1. Viruses are a pervasive component of microbial food webs in both marine and freshwater systems. The abundance of viruses in individual aquatic systems appears to be independent of salinity but related to the biomass of primary and secondary producers as well as seasonal effects. Burst size, virus production rate and the percentage of microbial cells carrying a viral burden also appear to be more closely correlated to trophic status than to salinity.

2. In marine environments, the roles of planktonic viruses as regulators of carbon and nutrient cycling as well as microbial community structure have been a focus of numerous studies, yet the roles of freshwater virioplankton remain much less studied. Nevertheless, a survey of published freshwater studies demonstrates that virioplankton recycle important quantities of growth‐limiting nutrients from hosts via generation of dead particulate and dissolved organic matter during cell lysis, and suggests that both the chemical speciation and concentration of these organic compounds and nutrients may have important influences on the microbial community.

3. Parallel observations on the spatial patterns and dynamics of microbial mortality due to viruses or grazing are more advanced in freshwaters than in marine environments. However, the constraints that determine whether virus‐ or grazer‐mediated mortality dominates are not yet understood in either environment.

4. Application of molecular approaches has facilitated the examination of the diversity and ecological dynamics of specific viral populations and entire communities. The depth of detail achieved in marine environments towards characterizing these populations and communities is just beginning to be matched in freshwater systems. The few available data suggest that viruses targeting‐related hosts in freshwater and marine systems may be genetically distinct.

5. Although the role of viruses in aquatic systems is complex and remains insufficiently studied, our survey of the literature indicates that, despite some differences, many of the controls on virioplankton activity and diversity are similar in marine and freshwater environments.
Bacteriophage morphotype and genome diversity in Seine River sediment
Authors: LEROY MAGALI , PRIGENT MAGALI , DUTERTRE MURIELLE , CONFALONIERI FABRICE , DUBOW MICHAEL
Published: May 2008

1. We investigated a sediment sample of the Seine River downstream of Paris for morphotype and genome diversity of bacteriophages using electron microscopy, pulsed‐field gel electrophoresis and a metagenomic analysis.

2. Short‐term incubations of the sediment in bacterial culture media, with or without addition of mitomycin C, were used to study the influence of pseudolysogens and induced lysis of lysogenic cells.

3. Electron microscopy of phages from the sediment revealed five morphotypes, whereas 13 morphotypes were observed after sediment incubation both with and without mitomycin C added. Pulsed‐field gel electrophoresis yielded seven size‐classes of double‐stranded DNA genomes.

4. Representatives of the three common families of tailed bacteriophages (Myoviridae, Siphoviridae or Podoviridae) were observed. Capsid sizes ranged from 85 to 200 nm in diameter and tail sizes from <50 nm to 265 nm in length.

5. PCR amplification of eubacterial 16S rDNA sequences from the incubated sediment revealed that the predominant bacteria were members of the Proteobacteria. In line with this result, sample analysis of metagenomic phage DNA libraries showed that phage‐homologous sequences were most similar to temperate phages infecting Proteobacteria. This correspondence supports the idea that temperate phages may play an important role in influencing the dynamics of bacterial hosts in river sediments.
Viruses in freshwater ecosystems: an introduction to the exploration of viruses in new aquatic habitats
Authors: MIDDELBOE MATHIAS , JACQUET STÉPHAN , WEINBAUER MARKUS
Published: May 2008

1. Viruses have become widely recognized as the most abundant biological entities and important players in aquatic environments, and this realization has profoundly changed our conceptual understanding of the functioning and regulation of aquatic ecosystems in the last two decades. However, most of this research has focussed on marine viruses, especially in pelagic environments.

2. Here we introduce a special issue of Freshwater Biology dealing with viruses in freshwater ecosystems. It represents the first attempt to summarize progress in freshwater viral ecology made by diverse research groups and to direct attention of viral ecologists towards fresh waters.

3. Six review‐type articles and ten original research papers cover a wide range of aspects of freshwater viral ecology. This includes reports on the distribution of freshwater viral communities in contrasting habitats (e.g. sediments, wetlands, littoral zone, open waters), on different roles of viruses in freshwater ecosystems (e.g. mortality rates of bacteria and phytoplankton, transduction, influence on bacterial diversity and organic matter), and on different types of viruses (bacteriophages, cyanophages, algal viruses, and a fish‐pathogenic virus).

4. Collectively the series of papers presented in this special issue indicates that freshwater environments cover great habitat diversity and that the significance of some of the mechanisms controlling viral dynamics and impacts may differ between freshwater and marine habitats.
Stereotomography assisted by migration of attributes
Authors: Nguyen Sylvain , Baina Reda , Alerini Mathias , Lambaré Gilles , Devaux Vincent , Noble Mark
Published: May 2008

Depth velocity model building remains a difficult step within the seismic depth imaging sequence. Stereotomography provides an efficient solution to this problem but was limited until now to a picking of seismic data in the prestack time un‐migrated domain. We propose here a method for stereotomographic data picking in the depth migrated domain. Picking in the depth migrated domain exhibits the advantage of a better signal‐to‐noise ratio and of a more regular distribution of picked events in the model, leading to a better constrained tomographic inverse problem. Moreover, any improvement on the velocity model will improve the migrated results, again leading to improved picking. Our strategy for obtaining a stereotomographic dataset from a prestack depth migration is based on migration of attributes (and not on a kinematic demigration approach!). For any locally coherent event in the migrated image, migration of attributes allows one to compute ray parameter attributes corresponding to the specular reflection angle and dip. For application to stereotomography, the necessary attributes are the source/receiver locations, the traveltime and the data slopes. For the data slope, when the migration velocity model is erroneous, some additional corrections have to be applied to the result of migration of the attributes. Applying these corrections, our picking method is theoretically valid whatever the quality of the migration velocity model. We first present the theoretical aspects of the method and then validate it on 2D synthetic and real seismic reflection data sets.
Seismic scale saturation relations in turbidite reservoirs undergoing waterflood
Authors: MacBeth Colin , Stephen Karl
Published: May 2008

Estimates of the effective fluid modulus from seismic cannot be directly converted to the true pore‐volume weighted mean saturation determined from fluid flow principles by using the saturation laws currently in use. One of the reasons is that seismic waves sample the reservoir geology and production induced saturation heterogeneity in a different way from the fluids. This mismatch prevents accurate quantitative evaluation of saturation changes from 4D seismic analysis. To tackle this problem, a reservoir‐related saturation law is developed for a turbidite reservoir – this geology being chosen because the architecture for a single sand package can be modelled as a stack of horizontal beds. An effective medium and perturbation theory are applied to the determination of the seismic properties of this model. This calculation provides a relationship that connects the true saturation to the effective fluid modulus from seismic via statistical measures of the vertical spread of the porosity and saturation variations in the reservoir. These statistics can be extracted from the simulation model and if known, enable the new saturation law to deliver a significant improvement in accuracy when estimating compared to other well‐known laws. The relationship that has been developed also captures the effect of inter‐bedded shales and can therefore be used to estimate true saturation in regions of the reservoir with moderate to low net‐to‐gross, provided the fraction of the shale component is known. In practice, the final choice of saturation law depends upon the reservoir information available, the assumptions that can be tolerated and the accuracy required in any particular reservoir characterization study.
Gpr83 expression is not required for the maintenance of intestinal immune homeostasis and regulation of T‐cell‐dependent colitis
Authors: Toms Christy , Jessup Heidi , Thompson Claire , Baban Dilair , Davies Kay , Powrie Fiona
Published: May 2008

Regulatory T (TR) cells are integral to the maintenance of intestinal homeostasis, where an intricate balance between tolerance and immunity must be maintained. Recently, studies have focused on the identification of molecules involved in the function and/or development of TR cells. One such molecule, the G‐protein coupled receptor Gpr83, has been identified through gene expression analysis as being overexpressed within thymic and peripheral naturally arising regulatory T (nTR) cell populations. The aim of this study was to further define the characteristics of Gpr83 expression and to investigate the role of Gpr83 in TR‐cell development and function through the generation and analysis of Gpr83‐deficient mice. Following activation, naïve CD4+ T cells induce Gpr83 expression in a transforming growth factor (TGF)‐β dependent manner. Rather than being a general marker of activation, Gpr83 expression could only be detected in cells also expressing forkhead/winged helix transcription factor (Foxp3), further supporting the association of Gpr83 with the regulatory cell phenotype. Mice deficient in Gpr83 expression developed normally and did not display signs of inflammatory disease. Thymic nTR‐cell development was unaffected by a lack of Gpr83 expression and peripheral nTR‐cell homeostasis was normal when compared with that of wild‐type mice. Gpr83 expression was dispensable for the regulatory activity of nTR cells as Gpr83‐deficient nTR cells could suppress the development of disease in a T‐cell transfer model of colitis. These results suggest a redundant role for Gpr83 in the function of TR cells in this model of disease. Further studies are required to determine the role of Gpr83 in TR‐cell biology.
Environmental stresses induce the expression of putative glycine‐rich insect cuticular protein genes in adult Leptinotarsa decemlineata (Say)
Authors: Zhang J. , Goyer C. , Pelletier Y.
Published: May 2008

The deposition of cuticular proteins in insects usually occurs during the moulting process. Three putative glycine‐rich insect cuticular proteins, Ld‐GRP1 to 3, were identified and characterized from the Colorado potato beetle, Leptinotarsa decemlineata. The Ld‐GRPs contained conserved GXGX and/or GGXG sequence repeats. Ld‐GRP1 also contained a conserved AAPA/V motif commonly found in cuticular proteins. The transcripts of Ld‐GRP1 and Ld‐GRP2 were detected in the epidermal cell layer by in situ hybridization, making them putative insect cuticular proteins. The putative cuticular protein genes were highly induced by the insecticide azinphosmethyl (organophosphorous) 2–3 weeks after adult moulting. Putative cuticular protein gene expression level was higher in azinphosmethyl‐resistant beetles than in susceptible beetles. Furthermore, two of the putative cuticular protein genes were highly induced by dry environmental conditions. These results suggest that the insect might increase cuticular component deposition in the adult stage in response to environmental stresses. This ability may allow the insect to adapt to new or changing environments.
Molecular cloning, partial genomic structure and functional characterization of succinic semialdehyde dehydrogenase genes from the parasitic insectsLucilia cuprinaandCtenocephalides felis
Authors: Rothacker B. , Werr M. , Ilg T.
Published: May 2008

The enzyme succinic semialdehyde dehydrogenase (SSADH; EC1.2.1.24) is a component of the γ‐aminobutyric acid degradation pathway in mammals and is essential for development and function of the nervous system. Here we report the identification, cDNA cloning and functional expression of SSADH from the parasitic insectsLucilia cuprinaandCtenocephalides felis. The recombinant proteins possess potent NAD+‐dependent SSADH activity, while their catalytic efficiency for other aldehyde substrates is lower. A genomic copy of theL. cuprinaSSADH gene contains two introns, while a genomic gene version ofC. felisis devoid of introns. In contrast to the single copy SSADH genes inDrosophila melanogasterand mammals, inL. cuprinaandC. felis, multiple SSADH gene copies are present in the genome.
Global and comparative protein profiles of the pronotum of the southern pine beetle, Dendroctonus frontalis
Authors: Pechanova O. , Stone W. D. , Monroe W. , Nebeker T. E. , Klepzig K. D. , Yuceer C.
Published: May 2008

The southern pine beetle (Dendroctonus frontalis Zimmermann) kills all pines within its range and is among the most important forest pest species in the US. Using a specialized mycangium surrounded by gland cells in the pronotum, adult females culture, transport, and inoculate two fungi into beetle galleries during oviposition. These fungal symbionts, to varying degrees, exclude antagonistic fungi and provide nutrients to larvae. However, the mechanisms (e.g. secreted antibiotic chemicals or nutrients, proteins or pathways) by which this relationship is maintained are not known. Here we present the first global and differential proteome profile of the southern pine beetle pronotum. Two‐dimensional polyacrylamide electrophoresis, tandem mass spectrometry, and database searches revealed that the majority of pronotal proteins were related to energy‐yielding metabolism, contractile apparati, cell structure, and defence. The identified proteins provide important insights into the molecular and biochemical processes of, and candidates for functional genomics to understand mycangia and pronotum functions in, the southern pine beetle.
The constituents of Microctonus sp. parasitoid venoms
Authors: Crawford A. M. , Brauning R. , Smolenski G. , Ferguson C. , Barton D. , Wheeler T. T. , Mcculloch A.
Published: May 2008

Purified RNA transcripts from venom glands dissected from the parasitoid wasp Microctonus hyperodae were copied, cloned and sequenced using traditional dideoxy sequencing methods. Using mass spectrometry analysis of the trypsinised PAGE gel protein bands we identified the RNA transcripts for the 3 most abundant proteins found in the venom and hence obtained their full protein sequence. Other abundant transcripts were also further sequenced. To reduce the effort required to obtain transcript information we dissected venom glands from a second parasitoid, Microctonus aethiopoides (Morocco biotype). The RNA transcripts were purified and reverse transcribed but instead of cloning the cDNA it was directly sequenced using Roche GS20 pyrosequencing. Results from a single GS20 sequencing run provided data similar to that obtained by the traditional methods used in analysing transcripts from M. hyperodae in a fraction of the time and cost. Comparing the transcripts between the two species showed that a similar range of genes are expressed with the putative orthologs of seven of the eight full length genes characterised from M. hyperodae being found in M. aethiopoides. Pyrosequencing should provide a valuable new method for rapidly sampling transcripts from a wide range of specialised insect tissues.
Characterization of the antimicrobial peptide attacin loci from Glossina morsitans
Authors: Wang J. , Hu C. , Wu Y. , Stuart A. , Amemiya C. , Berriman M. , Toyoda A. , Hattori M. , Aksoy S.
Published: May 2008

The antimicrobial peptide Attacin is an immune effector molecule that can inhibit the growth of gram‐negative bacteria. In Glossina morsitans morsitans, which serves as the sole vectors of African trypanosomes, Attacins also play a role in trypanosome resistance, and in maintaining parasite numbers at homeostatic levels in infected individuals. We characterized the attacin encoding loci from a Bacterial Artificial Chromosome (BAC) library. The attacin genes are organized into three clusters. Cluster 1 contains two attacin (attA) genes located in head‐to‐head orientation, cluster 2 contains two closely related genes (attA and attB) located in a similar transcriptional orientation, and cluster 3 contains a single attacin gene (attD). Coding and transcription regulatory sequences of attA and attB are nearly identical, but differ significantly from attD. Putative AttA and AttB have signal peptide sequences, but lack the pro domain typically present in insect Attacins. Putative AttD lacks both domains. Analysis of attacin cDNA sequences shows polymorphisms that could arise either from allelic variations or from the presence of additional attacin genomic loci. Real time‐PCR analysis reveals that attA and attB expression is induced in the fat body of flies per os challenged with Escherichia coli and parasitized with trypanosomes. In the midgut, expression of these attacins is similarly induced following microbial challenge, but reduced in response to parasite infections. Transcription of AttD is significantly less relative to the other two genes, and is preferentially induced in the fat body of parasitized flies. These results indicate that the different attacin genes may be differentially regulated.